diff options
author | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
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committer | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
commit | 849369d6c66d3054688672f97d31fceb8e8230fb (patch) | |
tree | 6135abc790ca67dedbe07c39806591e70eda81ce /drivers/base/power | |
download | linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.gz linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.bz2 linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.zip |
initial_commit
Diffstat (limited to 'drivers/base/power')
-rw-r--r-- | drivers/base/power/Makefile | 8 | ||||
-rw-r--r-- | drivers/base/power/clock_ops.c | 431 | ||||
-rw-r--r-- | drivers/base/power/generic_ops.c | 272 | ||||
-rw-r--r-- | drivers/base/power/main.c | 1188 | ||||
-rw-r--r-- | drivers/base/power/opp.c | 628 | ||||
-rw-r--r-- | drivers/base/power/power.h | 79 | ||||
-rw-r--r-- | drivers/base/power/runtime.c | 1263 | ||||
-rw-r--r-- | drivers/base/power/sysfs.c | 538 | ||||
-rw-r--r-- | drivers/base/power/trace.c | 265 | ||||
-rw-r--r-- | drivers/base/power/wakeup.c | 746 |
10 files changed, 5418 insertions, 0 deletions
diff --git a/drivers/base/power/Makefile b/drivers/base/power/Makefile new file mode 100644 index 00000000..3647e114 --- /dev/null +++ b/drivers/base/power/Makefile @@ -0,0 +1,8 @@ +obj-$(CONFIG_PM) += sysfs.o generic_ops.o +obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o +obj-$(CONFIG_PM_RUNTIME) += runtime.o +obj-$(CONFIG_PM_TRACE_RTC) += trace.o +obj-$(CONFIG_PM_OPP) += opp.o +obj-$(CONFIG_HAVE_CLK) += clock_ops.o + +ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG
\ No newline at end of file diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c new file mode 100644 index 00000000..ad367c41 --- /dev/null +++ b/drivers/base/power/clock_ops.c @@ -0,0 +1,431 @@ +/* + * drivers/base/power/clock_ops.c - Generic clock manipulation PM callbacks + * + * Copyright (c) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp. + * + * This file is released under the GPLv2. + */ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/io.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/clk.h> +#include <linux/slab.h> +#include <linux/err.h> + +#ifdef CONFIG_PM_RUNTIME + +struct pm_runtime_clk_data { + struct list_head clock_list; + struct mutex lock; +}; + +enum pce_status { + PCE_STATUS_NONE = 0, + PCE_STATUS_ACQUIRED, + PCE_STATUS_ENABLED, + PCE_STATUS_ERROR, +}; + +struct pm_clock_entry { + struct list_head node; + char *con_id; + struct clk *clk; + enum pce_status status; +}; + +static struct pm_runtime_clk_data *__to_prd(struct device *dev) +{ + return dev ? dev->power.subsys_data : NULL; +} + +/** + * pm_runtime_clk_add - Start using a device clock for runtime PM. + * @dev: Device whose clock is going to be used for runtime PM. + * @con_id: Connection ID of the clock. + * + * Add the clock represented by @con_id to the list of clocks used for + * the runtime PM of @dev. + */ +int pm_runtime_clk_add(struct device *dev, const char *con_id) +{ + struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clock_entry *ce; + + if (!prd) + return -EINVAL; + + ce = kzalloc(sizeof(*ce), GFP_KERNEL); + if (!ce) { + dev_err(dev, "Not enough memory for clock entry.\n"); + return -ENOMEM; + } + + if (con_id) { + ce->con_id = kstrdup(con_id, GFP_KERNEL); + if (!ce->con_id) { + dev_err(dev, + "Not enough memory for clock connection ID.\n"); + kfree(ce); + return -ENOMEM; + } + } + + mutex_lock(&prd->lock); + list_add_tail(&ce->node, &prd->clock_list); + mutex_unlock(&prd->lock); + return 0; +} + +/** + * __pm_runtime_clk_remove - Destroy runtime PM clock entry. + * @ce: Runtime PM clock entry to destroy. + * + * This routine must be called under the mutex protecting the runtime PM list + * of clocks corresponding the the @ce's device. + */ +static void __pm_runtime_clk_remove(struct pm_clock_entry *ce) +{ + if (!ce) + return; + + list_del(&ce->node); + + if (ce->status < PCE_STATUS_ERROR) { + if (ce->status == PCE_STATUS_ENABLED) + clk_disable(ce->clk); + + if (ce->status >= PCE_STATUS_ACQUIRED) + clk_put(ce->clk); + } + + if (ce->con_id) + kfree(ce->con_id); + + kfree(ce); +} + +/** + * pm_runtime_clk_remove - Stop using a device clock for runtime PM. + * @dev: Device whose clock should not be used for runtime PM any more. + * @con_id: Connection ID of the clock. + * + * Remove the clock represented by @con_id from the list of clocks used for + * the runtime PM of @dev. + */ +void pm_runtime_clk_remove(struct device *dev, const char *con_id) +{ + struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clock_entry *ce; + + if (!prd) + return; + + mutex_lock(&prd->lock); + + list_for_each_entry(ce, &prd->clock_list, node) { + if (!con_id && !ce->con_id) { + __pm_runtime_clk_remove(ce); + break; + } else if (!con_id || !ce->con_id) { + continue; + } else if (!strcmp(con_id, ce->con_id)) { + __pm_runtime_clk_remove(ce); + break; + } + } + + mutex_unlock(&prd->lock); +} + +/** + * pm_runtime_clk_init - Initialize a device's list of runtime PM clocks. + * @dev: Device to initialize the list of runtime PM clocks for. + * + * Allocate a struct pm_runtime_clk_data object, initialize its lock member and + * make the @dev's power.subsys_data field point to it. + */ +int pm_runtime_clk_init(struct device *dev) +{ + struct pm_runtime_clk_data *prd; + + prd = kzalloc(sizeof(*prd), GFP_KERNEL); + if (!prd) { + dev_err(dev, "Not enough memory fo runtime PM data.\n"); + return -ENOMEM; + } + + INIT_LIST_HEAD(&prd->clock_list); + mutex_init(&prd->lock); + dev->power.subsys_data = prd; + return 0; +} + +/** + * pm_runtime_clk_destroy - Destroy a device's list of runtime PM clocks. + * @dev: Device to destroy the list of runtime PM clocks for. + * + * Clear the @dev's power.subsys_data field, remove the list of clock entries + * from the struct pm_runtime_clk_data object pointed to by it before and free + * that object. + */ +void pm_runtime_clk_destroy(struct device *dev) +{ + struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clock_entry *ce, *c; + + if (!prd) + return; + + dev->power.subsys_data = NULL; + + mutex_lock(&prd->lock); + + list_for_each_entry_safe_reverse(ce, c, &prd->clock_list, node) + __pm_runtime_clk_remove(ce); + + mutex_unlock(&prd->lock); + + kfree(prd); +} + +/** + * pm_runtime_clk_acquire - Acquire a device clock. + * @dev: Device whose clock is to be acquired. + * @con_id: Connection ID of the clock. + */ +static void pm_runtime_clk_acquire(struct device *dev, + struct pm_clock_entry *ce) +{ + ce->clk = clk_get(dev, ce->con_id); + if (IS_ERR(ce->clk)) { + ce->status = PCE_STATUS_ERROR; + } else { + ce->status = PCE_STATUS_ACQUIRED; + dev_dbg(dev, "Clock %s managed by runtime PM.\n", ce->con_id); + } +} + +/** + * pm_runtime_clk_suspend - Disable clocks in a device's runtime PM clock list. + * @dev: Device to disable the clocks for. + */ +int pm_runtime_clk_suspend(struct device *dev) +{ + struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clock_entry *ce; + + dev_dbg(dev, "%s()\n", __func__); + + if (!prd) + return 0; + + mutex_lock(&prd->lock); + + list_for_each_entry_reverse(ce, &prd->clock_list, node) { + if (ce->status == PCE_STATUS_NONE) + pm_runtime_clk_acquire(dev, ce); + + if (ce->status < PCE_STATUS_ERROR) { + clk_disable(ce->clk); + ce->status = PCE_STATUS_ACQUIRED; + } + } + + mutex_unlock(&prd->lock); + + return 0; +} + +/** + * pm_runtime_clk_resume - Enable clocks in a device's runtime PM clock list. + * @dev: Device to enable the clocks for. + */ +int pm_runtime_clk_resume(struct device *dev) +{ + struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clock_entry *ce; + + dev_dbg(dev, "%s()\n", __func__); + + if (!prd) + return 0; + + mutex_lock(&prd->lock); + + list_for_each_entry(ce, &prd->clock_list, node) { + if (ce->status == PCE_STATUS_NONE) + pm_runtime_clk_acquire(dev, ce); + + if (ce->status < PCE_STATUS_ERROR) { + clk_enable(ce->clk); + ce->status = PCE_STATUS_ENABLED; + } + } + + mutex_unlock(&prd->lock); + + return 0; +} + +/** + * pm_runtime_clk_notify - Notify routine for device addition and removal. + * @nb: Notifier block object this function is a member of. + * @action: Operation being carried out by the caller. + * @data: Device the routine is being run for. + * + * For this function to work, @nb must be a member of an object of type + * struct pm_clk_notifier_block containing all of the requisite data. + * Specifically, the pwr_domain member of that object is copied to the device's + * pwr_domain field and its con_ids member is used to populate the device's list + * of runtime PM clocks, depending on @action. + * + * If the device's pwr_domain field is already populated with a value different + * from the one stored in the struct pm_clk_notifier_block object, the function + * does nothing. + */ +static int pm_runtime_clk_notify(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct pm_clk_notifier_block *clknb; + struct device *dev = data; + char **con_id; + int error; + + dev_dbg(dev, "%s() %ld\n", __func__, action); + + clknb = container_of(nb, struct pm_clk_notifier_block, nb); + + switch (action) { + case BUS_NOTIFY_ADD_DEVICE: + if (dev->pwr_domain) + break; + + error = pm_runtime_clk_init(dev); + if (error) + break; + + dev->pwr_domain = clknb->pwr_domain; + if (clknb->con_ids[0]) { + for (con_id = clknb->con_ids; *con_id; con_id++) + pm_runtime_clk_add(dev, *con_id); + } else { + pm_runtime_clk_add(dev, NULL); + } + + break; + case BUS_NOTIFY_DEL_DEVICE: + if (dev->pwr_domain != clknb->pwr_domain) + break; + + dev->pwr_domain = NULL; + pm_runtime_clk_destroy(dev); + break; + } + + return 0; +} + +#else /* !CONFIG_PM_RUNTIME */ + +/** + * enable_clock - Enable a device clock. + * @dev: Device whose clock is to be enabled. + * @con_id: Connection ID of the clock. + */ +static void enable_clock(struct device *dev, const char *con_id) +{ + struct clk *clk; + + clk = clk_get(dev, con_id); + if (!IS_ERR(clk)) { + clk_enable(clk); + clk_put(clk); + dev_info(dev, "Runtime PM disabled, clock forced on.\n"); + } +} + +/** + * disable_clock - Disable a device clock. + * @dev: Device whose clock is to be disabled. + * @con_id: Connection ID of the clock. + */ +static void disable_clock(struct device *dev, const char *con_id) +{ + struct clk *clk; + + clk = clk_get(dev, con_id); + if (!IS_ERR(clk)) { + clk_disable(clk); + clk_put(clk); + dev_info(dev, "Runtime PM disabled, clock forced off.\n"); + } +} + +/** + * pm_runtime_clk_notify - Notify routine for device addition and removal. + * @nb: Notifier block object this function is a member of. + * @action: Operation being carried out by the caller. + * @data: Device the routine is being run for. + * + * For this function to work, @nb must be a member of an object of type + * struct pm_clk_notifier_block containing all of the requisite data. + * Specifically, the con_ids member of that object is used to enable or disable + * the device's clocks, depending on @action. + */ +static int pm_runtime_clk_notify(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct pm_clk_notifier_block *clknb; + struct device *dev = data; + char **con_id; + + dev_dbg(dev, "%s() %ld\n", __func__, action); + + clknb = container_of(nb, struct pm_clk_notifier_block, nb); + + switch (action) { + case BUS_NOTIFY_BIND_DRIVER: + if (clknb->con_ids[0]) { + for (con_id = clknb->con_ids; *con_id; con_id++) + enable_clock(dev, *con_id); + } else { + enable_clock(dev, NULL); + } + break; + case BUS_NOTIFY_UNBOUND_DRIVER: + if (clknb->con_ids[0]) { + for (con_id = clknb->con_ids; *con_id; con_id++) + disable_clock(dev, *con_id); + } else { + disable_clock(dev, NULL); + } + break; + } + + return 0; +} + +#endif /* !CONFIG_PM_RUNTIME */ + +/** + * pm_runtime_clk_add_notifier - Add bus type notifier for runtime PM clocks. + * @bus: Bus type to add the notifier to. + * @clknb: Notifier to be added to the given bus type. + * + * The nb member of @clknb is not expected to be initialized and its + * notifier_call member will be replaced with pm_runtime_clk_notify(). However, + * the remaining members of @clknb should be populated prior to calling this + * routine. + */ +void pm_runtime_clk_add_notifier(struct bus_type *bus, + struct pm_clk_notifier_block *clknb) +{ + if (!bus || !clknb) + return; + + clknb->nb.notifier_call = pm_runtime_clk_notify; + bus_register_notifier(bus, &clknb->nb); +} diff --git a/drivers/base/power/generic_ops.c b/drivers/base/power/generic_ops.c new file mode 100644 index 00000000..cb3bb368 --- /dev/null +++ b/drivers/base/power/generic_ops.c @@ -0,0 +1,272 @@ +/* + * drivers/base/power/generic_ops.c - Generic PM callbacks for subsystems + * + * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + * + * This file is released under the GPLv2. + */ + +#include <linux/pm.h> +#include <linux/pm_runtime.h> + +#ifdef CONFIG_PM_RUNTIME +/** + * pm_generic_runtime_idle - Generic runtime idle callback for subsystems. + * @dev: Device to handle. + * + * If PM operations are defined for the @dev's driver and they include + * ->runtime_idle(), execute it and return its error code, if nonzero. + * Otherwise, execute pm_runtime_suspend() for the device and return 0. + */ +int pm_generic_runtime_idle(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + if (pm && pm->runtime_idle) { + int ret = pm->runtime_idle(dev); + if (ret) + return ret; + } + + pm_runtime_suspend(dev); + return 0; +} +EXPORT_SYMBOL_GPL(pm_generic_runtime_idle); + +/** + * pm_generic_runtime_suspend - Generic runtime suspend callback for subsystems. + * @dev: Device to suspend. + * + * If PM operations are defined for the @dev's driver and they include + * ->runtime_suspend(), execute it and return its error code. Otherwise, + * return 0. + */ +int pm_generic_runtime_suspend(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int ret; + + ret = pm && pm->runtime_suspend ? pm->runtime_suspend(dev) : 0; + + return ret; +} +EXPORT_SYMBOL_GPL(pm_generic_runtime_suspend); + +/** + * pm_generic_runtime_resume - Generic runtime resume callback for subsystems. + * @dev: Device to resume. + * + * If PM operations are defined for the @dev's driver and they include + * ->runtime_resume(), execute it and return its error code. Otherwise, + * return 0. + */ +int pm_generic_runtime_resume(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int ret; + + ret = pm && pm->runtime_resume ? pm->runtime_resume(dev) : 0; + + return ret; +} +EXPORT_SYMBOL_GPL(pm_generic_runtime_resume); +#endif /* CONFIG_PM_RUNTIME */ + +#ifdef CONFIG_PM_SLEEP +/** + * pm_generic_prepare - Generic routine preparing a device for power transition. + * @dev: Device to prepare. + * + * Prepare a device for a system-wide power transition. + */ +int pm_generic_prepare(struct device *dev) +{ + struct device_driver *drv = dev->driver; + int ret = 0; + + if (drv && drv->pm && drv->pm->prepare) + ret = drv->pm->prepare(dev); + + return ret; +} + +/** + * __pm_generic_call - Generic suspend/freeze/poweroff/thaw subsystem callback. + * @dev: Device to handle. + * @event: PM transition of the system under way. + * + * If the device has not been suspended at run time, execute the + * suspend/freeze/poweroff/thaw callback provided by its driver, if defined, and + * return its error code. Otherwise, return zero. + */ +static int __pm_generic_call(struct device *dev, int event) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int (*callback)(struct device *); + + if (!pm || pm_runtime_suspended(dev)) + return 0; + + switch (event) { + case PM_EVENT_SUSPEND: + callback = pm->suspend; + break; + case PM_EVENT_FREEZE: + callback = pm->freeze; + break; + case PM_EVENT_HIBERNATE: + callback = pm->poweroff; + break; + case PM_EVENT_THAW: + callback = pm->thaw; + break; + default: + callback = NULL; + break; + } + + return callback ? callback(dev) : 0; +} + +/** + * pm_generic_suspend - Generic suspend callback for subsystems. + * @dev: Device to suspend. + */ +int pm_generic_suspend(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_SUSPEND); +} +EXPORT_SYMBOL_GPL(pm_generic_suspend); + +/** + * pm_generic_freeze - Generic freeze callback for subsystems. + * @dev: Device to freeze. + */ +int pm_generic_freeze(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_FREEZE); +} +EXPORT_SYMBOL_GPL(pm_generic_freeze); + +/** + * pm_generic_poweroff - Generic poweroff callback for subsystems. + * @dev: Device to handle. + */ +int pm_generic_poweroff(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_HIBERNATE); +} +EXPORT_SYMBOL_GPL(pm_generic_poweroff); + +/** + * pm_generic_thaw - Generic thaw callback for subsystems. + * @dev: Device to thaw. + */ +int pm_generic_thaw(struct device *dev) +{ + return __pm_generic_call(dev, PM_EVENT_THAW); +} +EXPORT_SYMBOL_GPL(pm_generic_thaw); + +/** + * __pm_generic_resume - Generic resume/restore callback for subsystems. + * @dev: Device to handle. + * @event: PM transition of the system under way. + * + * Execute the resume/resotre callback provided by the @dev's driver, if + * defined. If it returns 0, change the device's runtime PM status to 'active'. + * Return the callback's error code. + */ +static int __pm_generic_resume(struct device *dev, int event) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int (*callback)(struct device *); + int ret; + + if (!pm) + return 0; + + switch (event) { + case PM_EVENT_RESUME: + callback = pm->resume; + break; + case PM_EVENT_RESTORE: + callback = pm->restore; + break; + default: + callback = NULL; + break; + } + + if (!callback) + return 0; + + ret = callback(dev); + if (!ret && pm_runtime_enabled(dev)) { + pm_runtime_disable(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + } + + return ret; +} + +/** + * pm_generic_resume - Generic resume callback for subsystems. + * @dev: Device to resume. + */ +int pm_generic_resume(struct device *dev) +{ + return __pm_generic_resume(dev, PM_EVENT_RESUME); +} +EXPORT_SYMBOL_GPL(pm_generic_resume); + +/** + * pm_generic_restore - Generic restore callback for subsystems. + * @dev: Device to restore. + */ +int pm_generic_restore(struct device *dev) +{ + return __pm_generic_resume(dev, PM_EVENT_RESTORE); +} +EXPORT_SYMBOL_GPL(pm_generic_restore); + +/** + * pm_generic_complete - Generic routine competing a device power transition. + * @dev: Device to handle. + * + * Complete a device power transition during a system-wide power transition. + */ +void pm_generic_complete(struct device *dev) +{ + struct device_driver *drv = dev->driver; + + if (drv && drv->pm && drv->pm->complete) + drv->pm->complete(dev); + + /* + * Let runtime PM try to suspend devices that haven't been in use before + * going into the system-wide sleep state we're resuming from. + */ + pm_runtime_idle(dev); +} +#endif /* CONFIG_PM_SLEEP */ + +struct dev_pm_ops generic_subsys_pm_ops = { +#ifdef CONFIG_PM_SLEEP + .prepare = pm_generic_prepare, + .suspend = pm_generic_suspend, + .resume = pm_generic_resume, + .freeze = pm_generic_freeze, + .thaw = pm_generic_thaw, + .poweroff = pm_generic_poweroff, + .restore = pm_generic_restore, + .complete = pm_generic_complete, +#endif +#ifdef CONFIG_PM_RUNTIME + .runtime_suspend = pm_generic_runtime_suspend, + .runtime_resume = pm_generic_runtime_resume, + .runtime_idle = pm_generic_runtime_idle, +#endif +}; +EXPORT_SYMBOL_GPL(generic_subsys_pm_ops); diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c new file mode 100644 index 00000000..b4e94fce --- /dev/null +++ b/drivers/base/power/main.c @@ -0,0 +1,1188 @@ +/* + * drivers/base/power/main.c - Where the driver meets power management. + * + * Copyright (c) 2003 Patrick Mochel + * Copyright (c) 2003 Open Source Development Lab + * + * This file is released under the GPLv2 + * + * + * The driver model core calls device_pm_add() when a device is registered. + * This will initialize the embedded device_pm_info object in the device + * and add it to the list of power-controlled devices. sysfs entries for + * controlling device power management will also be added. + * + * A separate list is used for keeping track of power info, because the power + * domain dependencies may differ from the ancestral dependencies that the + * subsystem list maintains. + */ + +#include <linux/device.h> +#include <linux/kallsyms.h> +#include <linux/mutex.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/resume-trace.h> +#include <linux/interrupt.h> +#include <linux/sched.h> +#include <linux/async.h> +#include <linux/suspend.h> +#include <linux/timer.h> + +#include "../base.h" +#include "power.h" + +/* + * The entries in the dpm_list list are in a depth first order, simply + * because children are guaranteed to be discovered after parents, and + * are inserted at the back of the list on discovery. + * + * Since device_pm_add() may be called with a device lock held, + * we must never try to acquire a device lock while holding + * dpm_list_mutex. + */ + +LIST_HEAD(dpm_list); +LIST_HEAD(dpm_prepared_list); +LIST_HEAD(dpm_suspended_list); +LIST_HEAD(dpm_noirq_list); + +static DEFINE_MUTEX(dpm_list_mtx); +static pm_message_t pm_transition; + +static void dpm_drv_timeout(unsigned long data); +struct dpm_drv_wd_data { + struct device *dev; + struct task_struct *tsk; +}; + +static int async_error; + +/** + * device_pm_init - Initialize the PM-related part of a device object. + * @dev: Device object being initialized. + */ +void device_pm_init(struct device *dev) +{ + dev->power.is_prepared = false; + dev->power.is_suspended = false; + init_completion(&dev->power.completion); + complete_all(&dev->power.completion); + dev->power.wakeup = NULL; + spin_lock_init(&dev->power.lock); + pm_runtime_init(dev); + INIT_LIST_HEAD(&dev->power.entry); +} + +/** + * device_pm_lock - Lock the list of active devices used by the PM core. + */ +void device_pm_lock(void) +{ + mutex_lock(&dpm_list_mtx); +} + +/** + * device_pm_unlock - Unlock the list of active devices used by the PM core. + */ +void device_pm_unlock(void) +{ + mutex_unlock(&dpm_list_mtx); +} + +/** + * device_pm_add - Add a device to the PM core's list of active devices. + * @dev: Device to add to the list. + */ +void device_pm_add(struct device *dev) +{ + pr_debug("PM: Adding info for %s:%s\n", + dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); + mutex_lock(&dpm_list_mtx); + if (dev->parent && dev->parent->power.is_prepared) + dev_warn(dev, "parent %s should not be sleeping\n", + dev_name(dev->parent)); + list_add_tail(&dev->power.entry, &dpm_list); + mutex_unlock(&dpm_list_mtx); +} + +/** + * device_pm_remove - Remove a device from the PM core's list of active devices. + * @dev: Device to be removed from the list. + */ +void device_pm_remove(struct device *dev) +{ + pr_debug("PM: Removing info for %s:%s\n", + dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); + complete_all(&dev->power.completion); + mutex_lock(&dpm_list_mtx); + list_del_init(&dev->power.entry); + mutex_unlock(&dpm_list_mtx); + device_wakeup_disable(dev); + pm_runtime_remove(dev); +} + +/** + * device_pm_move_before - Move device in the PM core's list of active devices. + * @deva: Device to move in dpm_list. + * @devb: Device @deva should come before. + */ +void device_pm_move_before(struct device *deva, struct device *devb) +{ + pr_debug("PM: Moving %s:%s before %s:%s\n", + deva->bus ? deva->bus->name : "No Bus", dev_name(deva), + devb->bus ? devb->bus->name : "No Bus", dev_name(devb)); + /* Delete deva from dpm_list and reinsert before devb. */ + list_move_tail(&deva->power.entry, &devb->power.entry); +} + +/** + * device_pm_move_after - Move device in the PM core's list of active devices. + * @deva: Device to move in dpm_list. + * @devb: Device @deva should come after. + */ +void device_pm_move_after(struct device *deva, struct device *devb) +{ + pr_debug("PM: Moving %s:%s after %s:%s\n", + deva->bus ? deva->bus->name : "No Bus", dev_name(deva), + devb->bus ? devb->bus->name : "No Bus", dev_name(devb)); + /* Delete deva from dpm_list and reinsert after devb. */ + list_move(&deva->power.entry, &devb->power.entry); +} + +/** + * device_pm_move_last - Move device to end of the PM core's list of devices. + * @dev: Device to move in dpm_list. + */ +void device_pm_move_last(struct device *dev) +{ + pr_debug("PM: Moving %s:%s to end of list\n", + dev->bus ? dev->bus->name : "No Bus", dev_name(dev)); + list_move_tail(&dev->power.entry, &dpm_list); +} + +static ktime_t initcall_debug_start(struct device *dev) +{ + ktime_t calltime = ktime_set(0, 0); + + if (initcall_debug) { + pr_info("calling %s+ @ %i\n", + dev_name(dev), task_pid_nr(current)); + calltime = ktime_get(); + } + + return calltime; +} + +static void initcall_debug_report(struct device *dev, ktime_t calltime, + int error) +{ + ktime_t delta, rettime; + + if (initcall_debug) { + rettime = ktime_get(); + delta = ktime_sub(rettime, calltime); + pr_info("call %s+ returned %d after %Ld usecs\n", dev_name(dev), + error, (unsigned long long)ktime_to_ns(delta) >> 10); + } +} +#ifdef CONFIG_SUSPEND_DEVICE_TIME_DEBUG +static void suspend_time_debug_start(ktime_t *start) +{ + *start = ktime_get(); +} + +static void suspend_time_debug_report(const char *name, struct device *dev, + ktime_t starttime) +{ + ktime_t rettime; + s64 usecs64; + int usecs; + + if (!dev->driver) + return; + + rettime = ktime_get(); + usecs64 = ktime_to_us(ktime_sub(rettime, starttime)); + usecs = usecs64; + if (usecs == 0) + usecs = 1; + + if (device_suspend_time_threshold + && usecs > device_suspend_time_threshold) + pr_info("PM: device %s:%s %s too slow, it takes \t %ld.%03ld msecs\n", + dev->bus->name, dev_name(dev), name, + usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC); +} +#else +static void suspend_time_debug_start(ktime_t *start) {} +static void suspend_time_debug_report(const char *name, struct device *dev, + ktime_t starttime) {} +#endif /* CONFIG_SUSPEND_DEVICE_TIME_DEBUG */ + +/** + * dpm_wait - Wait for a PM operation to complete. + * @dev: Device to wait for. + * @async: If unset, wait only if the device's power.async_suspend flag is set. + */ +static void dpm_wait(struct device *dev, bool async) +{ + if (!dev) + return; + + if (async || (pm_async_enabled && dev->power.async_suspend)) + wait_for_completion(&dev->power.completion); +} + +static int dpm_wait_fn(struct device *dev, void *async_ptr) +{ + dpm_wait(dev, *((bool *)async_ptr)); + return 0; +} + +static void dpm_wait_for_children(struct device *dev, bool async) +{ + device_for_each_child(dev, &async, dpm_wait_fn); +} + +/** + * pm_op - Execute the PM operation appropriate for given PM event. + * @dev: Device to handle. + * @ops: PM operations to choose from. + * @state: PM transition of the system being carried out. + */ +static int pm_op(struct device *dev, + const struct dev_pm_ops *ops, + pm_message_t state) +{ + int error = 0; + ktime_t calltime, starttime; + + calltime = initcall_debug_start(dev); + + switch (state.event) { +#ifdef CONFIG_SUSPEND + case PM_EVENT_SUSPEND: + if (ops->suspend) { + suspend_time_debug_start(&starttime); + error = ops->suspend(dev); + suspend_time_debug_report("suspend", dev, starttime); + suspend_report_result(ops->suspend, error); + } + break; + case PM_EVENT_RESUME: + if (ops->resume) { + suspend_time_debug_start(&starttime); + error = ops->resume(dev); + suspend_time_debug_report("resume", dev, starttime); + suspend_report_result(ops->resume, error); + } + break; +#endif /* CONFIG_SUSPEND */ +#ifdef CONFIG_HIBERNATE_CALLBACKS + case PM_EVENT_FREEZE: + case PM_EVENT_QUIESCE: + if (ops->freeze) { + error = ops->freeze(dev); + suspend_report_result(ops->freeze, error); + } + break; + case PM_EVENT_HIBERNATE: + if (ops->poweroff) { + error = ops->poweroff(dev); + suspend_report_result(ops->poweroff, error); + } + break; + case PM_EVENT_THAW: + case PM_EVENT_RECOVER: + if (ops->thaw) { + error = ops->thaw(dev); + suspend_report_result(ops->thaw, error); + } + break; + case PM_EVENT_RESTORE: + if (ops->restore) { + error = ops->restore(dev); + suspend_report_result(ops->restore, error); + } + break; +#endif /* CONFIG_HIBERNATE_CALLBACKS */ + default: + error = -EINVAL; + } + + initcall_debug_report(dev, calltime, error); + + return error; +} + +/** + * pm_noirq_op - Execute the PM operation appropriate for given PM event. + * @dev: Device to handle. + * @ops: PM operations to choose from. + * @state: PM transition of the system being carried out. + * + * The driver of @dev will not receive interrupts while this function is being + * executed. + */ +static int pm_noirq_op(struct device *dev, + const struct dev_pm_ops *ops, + pm_message_t state) +{ + int error = 0; + ktime_t calltime = ktime_set(0, 0), delta, rettime; + + if (initcall_debug) { + pr_info("calling %s+ @ %i, parent: %s\n", + dev_name(dev), task_pid_nr(current), + dev->parent ? dev_name(dev->parent) : "none"); + calltime = ktime_get(); + } + + switch (state.event) { +#ifdef CONFIG_SUSPEND + case PM_EVENT_SUSPEND: + if (ops->suspend_noirq) { + error = ops->suspend_noirq(dev); + suspend_report_result(ops->suspend_noirq, error); + } + break; + case PM_EVENT_RESUME: + if (ops->resume_noirq) { + error = ops->resume_noirq(dev); + suspend_report_result(ops->resume_noirq, error); + } + break; +#endif /* CONFIG_SUSPEND */ +#ifdef CONFIG_HIBERNATE_CALLBACKS + case PM_EVENT_FREEZE: + case PM_EVENT_QUIESCE: + if (ops->freeze_noirq) { + error = ops->freeze_noirq(dev); + suspend_report_result(ops->freeze_noirq, error); + } + break; + case PM_EVENT_HIBERNATE: + if (ops->poweroff_noirq) { + error = ops->poweroff_noirq(dev); + suspend_report_result(ops->poweroff_noirq, error); + } + break; + case PM_EVENT_THAW: + case PM_EVENT_RECOVER: + if (ops->thaw_noirq) { + error = ops->thaw_noirq(dev); + suspend_report_result(ops->thaw_noirq, error); + } + break; + case PM_EVENT_RESTORE: + if (ops->restore_noirq) { + error = ops->restore_noirq(dev); + suspend_report_result(ops->restore_noirq, error); + } + break; +#endif /* CONFIG_HIBERNATE_CALLBACKS */ + default: + error = -EINVAL; + } + + if (initcall_debug) { + rettime = ktime_get(); + delta = ktime_sub(rettime, calltime); + printk("initcall %s_i+ returned %d after %Ld usecs\n", + dev_name(dev), error, + (unsigned long long)ktime_to_ns(delta) >> 10); + } + + return error; +} + +static char *pm_verb(int event) +{ + switch (event) { + case PM_EVENT_SUSPEND: + return "suspend"; + case PM_EVENT_RESUME: + return "resume"; + case PM_EVENT_FREEZE: + return "freeze"; + case PM_EVENT_QUIESCE: + return "quiesce"; + case PM_EVENT_HIBERNATE: + return "hibernate"; + case PM_EVENT_THAW: + return "thaw"; + case PM_EVENT_RESTORE: + return "restore"; + case PM_EVENT_RECOVER: + return "recover"; + default: + return "(unknown PM event)"; + } +} + +static void pm_dev_dbg(struct device *dev, pm_message_t state, char *info) +{ + dev_dbg(dev, "%s%s%s\n", info, pm_verb(state.event), + ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ? + ", may wakeup" : ""); +} + +static void pm_dev_err(struct device *dev, pm_message_t state, char *info, + int error) +{ + printk(KERN_ERR "PM: Device %s failed to %s%s: error %d\n", + dev_name(dev), pm_verb(state.event), info, error); +} + +static void dpm_show_time(ktime_t starttime, pm_message_t state, char *info) +{ + ktime_t calltime; + u64 usecs64; + int usecs; + + calltime = ktime_get(); + usecs64 = ktime_to_ns(ktime_sub(calltime, starttime)); + do_div(usecs64, NSEC_PER_USEC); + usecs = usecs64; + if (usecs == 0) + usecs = 1; + pr_info("PM: %s%s%s of devices complete after %ld.%03ld msecs\n", + info ?: "", info ? " " : "", pm_verb(state.event), + usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC); +} + +/*------------------------- Resume routines -------------------------*/ + +/** + * device_resume_noirq - Execute an "early resume" callback for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * + * The driver of @dev will not receive interrupts while this function is being + * executed. + */ +static int device_resume_noirq(struct device *dev, pm_message_t state) +{ + int error = 0; + + TRACE_DEVICE(dev); + TRACE_RESUME(0); + + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "EARLY power domain "); + error = pm_noirq_op(dev, &dev->pwr_domain->ops, state); + } else if (dev->type && dev->type->pm) { + pm_dev_dbg(dev, state, "EARLY type "); + error = pm_noirq_op(dev, dev->type->pm, state); + } else if (dev->class && dev->class->pm) { + pm_dev_dbg(dev, state, "EARLY class "); + error = pm_noirq_op(dev, dev->class->pm, state); + } else if (dev->bus && dev->bus->pm) { + pm_dev_dbg(dev, state, "EARLY "); + error = pm_noirq_op(dev, dev->bus->pm, state); + } + + TRACE_RESUME(error); + return error; +} + +/** + * dpm_resume_noirq - Execute "early resume" callbacks for non-sysdev devices. + * @state: PM transition of the system being carried out. + * + * Call the "noirq" resume handlers for all devices marked as DPM_OFF_IRQ and + * enable device drivers to receive interrupts. + */ +void dpm_resume_noirq(pm_message_t state) +{ + ktime_t starttime = ktime_get(); + + mutex_lock(&dpm_list_mtx); + while (!list_empty(&dpm_noirq_list)) { + struct device *dev = to_device(dpm_noirq_list.next); + int error; + + get_device(dev); + list_move_tail(&dev->power.entry, &dpm_suspended_list); + mutex_unlock(&dpm_list_mtx); + + error = device_resume_noirq(dev, state); + if (error) + pm_dev_err(dev, state, " early", error); + + mutex_lock(&dpm_list_mtx); + put_device(dev); + } + mutex_unlock(&dpm_list_mtx); + dpm_show_time(starttime, state, "early"); + resume_device_irqs(); +} +EXPORT_SYMBOL_GPL(dpm_resume_noirq); + +/** + * legacy_resume - Execute a legacy (bus or class) resume callback for device. + * @dev: Device to resume. + * @cb: Resume callback to execute. + */ +static int legacy_resume(struct device *dev, int (*cb)(struct device *dev)) +{ + int error; + ktime_t calltime; + + calltime = initcall_debug_start(dev); + + error = cb(dev); + suspend_report_result(cb, error); + + initcall_debug_report(dev, calltime, error); + + return error; +} + +/** + * device_resume - Execute "resume" callbacks for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * @async: If true, the device is being resumed asynchronously. + */ +static int device_resume(struct device *dev, pm_message_t state, bool async) +{ + int error = 0; + + TRACE_DEVICE(dev); + TRACE_RESUME(0); + + dpm_wait(dev->parent, async); + device_lock(dev); + + /* + * This is a fib. But we'll allow new children to be added below + * a resumed device, even if the device hasn't been completed yet. + */ + dev->power.is_prepared = false; + + if (!dev->power.is_suspended) + goto Unlock; + + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "power domain "); + error = pm_op(dev, &dev->pwr_domain->ops, state); + goto End; + } + + if (dev->type && dev->type->pm) { + pm_dev_dbg(dev, state, "type "); + error = pm_op(dev, dev->type->pm, state); + goto End; + } + + if (dev->class) { + if (dev->class->pm) { + pm_dev_dbg(dev, state, "class "); + error = pm_op(dev, dev->class->pm, state); + goto End; + } else if (dev->class->resume) { + pm_dev_dbg(dev, state, "legacy class "); + error = legacy_resume(dev, dev->class->resume); + goto End; + } + } + + if (dev->bus) { + if (dev->bus->pm) { + pm_dev_dbg(dev, state, ""); + error = pm_op(dev, dev->bus->pm, state); + } else if (dev->bus->resume) { + pm_dev_dbg(dev, state, "legacy "); + error = legacy_resume(dev, dev->bus->resume); + } + } + + End: + dev->power.is_suspended = false; + + Unlock: + device_unlock(dev); + complete_all(&dev->power.completion); + + TRACE_RESUME(error); + return error; +} + +static void async_resume(void *data, async_cookie_t cookie) +{ + struct device *dev = (struct device *)data; + int error; + + error = device_resume(dev, pm_transition, true); + if (error) + pm_dev_err(dev, pm_transition, " async", error); + put_device(dev); +} + +static bool is_async(struct device *dev) +{ + return dev->power.async_suspend && pm_async_enabled + && !pm_trace_is_enabled(); +} + +/** + * dpm_drv_timeout - Driver suspend / resume watchdog handler + * @data: struct device which timed out + * + * Called when a driver has timed out suspending or resuming. + * There's not much we can do here to recover so + * BUG() out for a crash-dump + * + */ +static void dpm_drv_timeout(unsigned long data) +{ + struct dpm_drv_wd_data *wd_data = (void *)data; + struct device *dev = wd_data->dev; + struct task_struct *tsk = wd_data->tsk; + + printk(KERN_EMERG "**** DPM device timeout: %s (%s)\n", dev_name(dev), + (dev->driver ? dev->driver->name : "no driver")); + + printk(KERN_EMERG "dpm suspend stack:\n"); + show_stack(tsk, NULL); + + BUG(); +} + +/** + * dpm_resume - Execute "resume" callbacks for non-sysdev devices. + * @state: PM transition of the system being carried out. + * + * Execute the appropriate "resume" callback for all devices whose status + * indicates that they are suspended. + */ +void dpm_resume(pm_message_t state) +{ + struct device *dev; + ktime_t starttime = ktime_get(); + + might_sleep(); + + mutex_lock(&dpm_list_mtx); + pm_transition = state; + async_error = 0; + + list_for_each_entry(dev, &dpm_suspended_list, power.entry) { + INIT_COMPLETION(dev->power.completion); + if (is_async(dev)) { + get_device(dev); + async_schedule(async_resume, dev); + } + } + + while (!list_empty(&dpm_suspended_list)) { + dev = to_device(dpm_suspended_list.next); + get_device(dev); + if (!is_async(dev)) { + int error; + + mutex_unlock(&dpm_list_mtx); + + error = device_resume(dev, state, false); + if (error) + pm_dev_err(dev, state, "", error); + + mutex_lock(&dpm_list_mtx); + } + if (!list_empty(&dev->power.entry)) + list_move_tail(&dev->power.entry, &dpm_prepared_list); + put_device(dev); + } + mutex_unlock(&dpm_list_mtx); + async_synchronize_full(); + dpm_show_time(starttime, state, NULL); +} + +/** + * device_complete - Complete a PM transition for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + */ +static void device_complete(struct device *dev, pm_message_t state) +{ + device_lock(dev); + + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "completing power domain "); + if (dev->pwr_domain->ops.complete) + dev->pwr_domain->ops.complete(dev); + } else if (dev->type && dev->type->pm) { + pm_dev_dbg(dev, state, "completing type "); + if (dev->type->pm->complete) + dev->type->pm->complete(dev); + } else if (dev->class && dev->class->pm) { + pm_dev_dbg(dev, state, "completing class "); + if (dev->class->pm->complete) + dev->class->pm->complete(dev); + } else if (dev->bus && dev->bus->pm) { + pm_dev_dbg(dev, state, "completing "); + if (dev->bus->pm->complete) + dev->bus->pm->complete(dev); + } + + device_unlock(dev); +} + +/** + * dpm_complete - Complete a PM transition for all non-sysdev devices. + * @state: PM transition of the system being carried out. + * + * Execute the ->complete() callbacks for all devices whose PM status is not + * DPM_ON (this allows new devices to be registered). + */ +void dpm_complete(pm_message_t state) +{ + struct list_head list; + + might_sleep(); + + INIT_LIST_HEAD(&list); + mutex_lock(&dpm_list_mtx); + while (!list_empty(&dpm_prepared_list)) { + struct device *dev = to_device(dpm_prepared_list.prev); + + get_device(dev); + dev->power.is_prepared = false; + list_move(&dev->power.entry, &list); + mutex_unlock(&dpm_list_mtx); + + device_complete(dev, state); + + mutex_lock(&dpm_list_mtx); + put_device(dev); + } + list_splice(&list, &dpm_list); + mutex_unlock(&dpm_list_mtx); +} + +/** + * dpm_resume_end - Execute "resume" callbacks and complete system transition. + * @state: PM transition of the system being carried out. + * + * Execute "resume" callbacks for all devices and complete the PM transition of + * the system. + */ +void dpm_resume_end(pm_message_t state) +{ + dpm_resume(state); + dpm_complete(state); +} +EXPORT_SYMBOL_GPL(dpm_resume_end); + + +/*------------------------- Suspend routines -------------------------*/ + +/** + * resume_event - Return a "resume" message for given "suspend" sleep state. + * @sleep_state: PM message representing a sleep state. + * + * Return a PM message representing the resume event corresponding to given + * sleep state. + */ +static pm_message_t resume_event(pm_message_t sleep_state) +{ + switch (sleep_state.event) { + case PM_EVENT_SUSPEND: + return PMSG_RESUME; + case PM_EVENT_FREEZE: + case PM_EVENT_QUIESCE: + return PMSG_RECOVER; + case PM_EVENT_HIBERNATE: + return PMSG_RESTORE; + } + return PMSG_ON; +} + +/** + * device_suspend_noirq - Execute a "late suspend" callback for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * + * The driver of @dev will not receive interrupts while this function is being + * executed. + */ +static int device_suspend_noirq(struct device *dev, pm_message_t state) +{ + int error; + + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "LATE power domain "); + error = pm_noirq_op(dev, &dev->pwr_domain->ops, state); + if (error) + return error; + } else if (dev->type && dev->type->pm) { + pm_dev_dbg(dev, state, "LATE type "); + error = pm_noirq_op(dev, dev->type->pm, state); + if (error) + return error; + } else if (dev->class && dev->class->pm) { + pm_dev_dbg(dev, state, "LATE class "); + error = pm_noirq_op(dev, dev->class->pm, state); + if (error) + return error; + } else if (dev->bus && dev->bus->pm) { + pm_dev_dbg(dev, state, "LATE "); + error = pm_noirq_op(dev, dev->bus->pm, state); + if (error) + return error; + } + + return 0; +} + +/** + * dpm_suspend_noirq - Execute "late suspend" callbacks for non-sysdev devices. + * @state: PM transition of the system being carried out. + * + * Prevent device drivers from receiving interrupts and call the "noirq" suspend + * handlers for all non-sysdev devices. + */ +int dpm_suspend_noirq(pm_message_t state) +{ + ktime_t starttime = ktime_get(); + int error = 0; + + suspend_device_irqs(); + mutex_lock(&dpm_list_mtx); + while (!list_empty(&dpm_suspended_list)) { + struct device *dev = to_device(dpm_suspended_list.prev); + + get_device(dev); + mutex_unlock(&dpm_list_mtx); + + error = device_suspend_noirq(dev, state); + + mutex_lock(&dpm_list_mtx); + if (error) { + pm_dev_err(dev, state, " late", error); + put_device(dev); + break; + } + if (!list_empty(&dev->power.entry)) + list_move(&dev->power.entry, &dpm_noirq_list); + put_device(dev); + } + mutex_unlock(&dpm_list_mtx); + if (error) { + resume_irqs(true); + dpm_resume_noirq(resume_event(state)); + } + else + dpm_show_time(starttime, state, "late"); + return error; +} +EXPORT_SYMBOL_GPL(dpm_suspend_noirq); + +/** + * legacy_suspend - Execute a legacy (bus or class) suspend callback for device. + * @dev: Device to suspend. + * @state: PM transition of the system being carried out. + * @cb: Suspend callback to execute. + */ +static int legacy_suspend(struct device *dev, pm_message_t state, + int (*cb)(struct device *dev, pm_message_t state)) +{ + int error; + ktime_t calltime; + + calltime = initcall_debug_start(dev); + + error = cb(dev, state); + suspend_report_result(cb, error); + + initcall_debug_report(dev, calltime, error); + + return error; +} + +/** + * device_suspend - Execute "suspend" callbacks for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * @async: If true, the device is being suspended asynchronously. + */ +static int __device_suspend(struct device *dev, pm_message_t state, bool async) +{ + int error = 0; + struct timer_list timer; + struct dpm_drv_wd_data data; + + dpm_wait_for_children(dev, async); + + data.dev = dev; + data.tsk = get_current(); + init_timer_on_stack(&timer); + timer.expires = jiffies + HZ * 12; + timer.function = dpm_drv_timeout; + timer.data = (unsigned long)&data; + add_timer(&timer); + + device_lock(dev); + + if (async_error) + goto Unlock; + + if (pm_wakeup_pending()) { + async_error = -EBUSY; + goto Unlock; + } + + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "power domain "); + error = pm_op(dev, &dev->pwr_domain->ops, state); + goto End; + } + + if (dev->type && dev->type->pm) { + pm_dev_dbg(dev, state, "type "); + error = pm_op(dev, dev->type->pm, state); + goto End; + } + + if (dev->class) { + if (dev->class->pm) { + pm_dev_dbg(dev, state, "class "); + error = pm_op(dev, dev->class->pm, state); + goto End; + } else if (dev->class->suspend) { + pm_dev_dbg(dev, state, "legacy class "); + error = legacy_suspend(dev, state, dev->class->suspend); + goto End; + } + } + + if (dev->bus) { + if (dev->bus->pm) { + pm_dev_dbg(dev, state, ""); + error = pm_op(dev, dev->bus->pm, state); + } else if (dev->bus->suspend) { + pm_dev_dbg(dev, state, "legacy "); + error = legacy_suspend(dev, state, dev->bus->suspend); + } + } + + End: + dev->power.is_suspended = !error; + + Unlock: + device_unlock(dev); + + del_timer_sync(&timer); + destroy_timer_on_stack(&timer); + + complete_all(&dev->power.completion); + + if (error) + async_error = error; + + return error; +} + +static void async_suspend(void *data, async_cookie_t cookie) +{ + struct device *dev = (struct device *)data; + int error; + + error = __device_suspend(dev, pm_transition, true); + if (error) + pm_dev_err(dev, pm_transition, " async", error); + + put_device(dev); +} + +static int device_suspend(struct device *dev) +{ + INIT_COMPLETION(dev->power.completion); + + if (pm_async_enabled && dev->power.async_suspend) { + get_device(dev); + async_schedule(async_suspend, dev); + return 0; + } + + return __device_suspend(dev, pm_transition, false); +} + +/** + * dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices. + * @state: PM transition of the system being carried out. + */ +int dpm_suspend(pm_message_t state) +{ + ktime_t starttime = ktime_get(); + int error = 0; + + might_sleep(); + + mutex_lock(&dpm_list_mtx); + pm_transition = state; + async_error = 0; + while (!list_empty(&dpm_prepared_list)) { + struct device *dev = to_device(dpm_prepared_list.prev); + + get_device(dev); + mutex_unlock(&dpm_list_mtx); + + error = device_suspend(dev); + + mutex_lock(&dpm_list_mtx); + if (error) { + pm_dev_err(dev, state, "", error); + put_device(dev); + break; + } + if (!list_empty(&dev->power.entry)) + list_move(&dev->power.entry, &dpm_suspended_list); + put_device(dev); + if (async_error) + break; + } + mutex_unlock(&dpm_list_mtx); + async_synchronize_full(); + if (!error) + error = async_error; + if (!error) + dpm_show_time(starttime, state, NULL); + return error; +} + +/** + * device_prepare - Prepare a device for system power transition. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * + * Execute the ->prepare() callback(s) for given device. No new children of the + * device may be registered after this function has returned. + */ +static int device_prepare(struct device *dev, pm_message_t state) +{ + int error = 0; + + device_lock(dev); + + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "preparing power domain "); + if (dev->pwr_domain->ops.prepare) + error = dev->pwr_domain->ops.prepare(dev); + suspend_report_result(dev->pwr_domain->ops.prepare, error); + if (error) + goto End; + } else if (dev->type && dev->type->pm) { + pm_dev_dbg(dev, state, "preparing type "); + if (dev->type->pm->prepare) + error = dev->type->pm->prepare(dev); + suspend_report_result(dev->type->pm->prepare, error); + if (error) + goto End; + } else if (dev->class && dev->class->pm) { + pm_dev_dbg(dev, state, "preparing class "); + if (dev->class->pm->prepare) + error = dev->class->pm->prepare(dev); + suspend_report_result(dev->class->pm->prepare, error); + if (error) + goto End; + } else if (dev->bus && dev->bus->pm) { + pm_dev_dbg(dev, state, "preparing "); + if (dev->bus->pm->prepare) + error = dev->bus->pm->prepare(dev); + suspend_report_result(dev->bus->pm->prepare, error); + } + + End: + device_unlock(dev); + + return error; +} + +/** + * dpm_prepare - Prepare all non-sysdev devices for a system PM transition. + * @state: PM transition of the system being carried out. + * + * Execute the ->prepare() callback(s) for all devices. + */ +int dpm_prepare(pm_message_t state) +{ + int error = 0; + + might_sleep(); + + mutex_lock(&dpm_list_mtx); + while (!list_empty(&dpm_list)) { + struct device *dev = to_device(dpm_list.next); + + get_device(dev); + mutex_unlock(&dpm_list_mtx); + + pm_runtime_get_noresume(dev); + if (pm_runtime_barrier(dev) && device_may_wakeup(dev)) + pm_wakeup_event(dev, 0); + + pm_runtime_put_sync(dev); + error = pm_wakeup_pending() ? + -EBUSY : device_prepare(dev, state); + + mutex_lock(&dpm_list_mtx); + if (error) { + if (error == -EAGAIN) { + put_device(dev); + error = 0; + continue; + } + printk(KERN_INFO "PM: Device %s not prepared " + "for power transition: code %d\n", + dev_name(dev), error); + put_device(dev); + break; + } + dev->power.is_prepared = true; + if (!list_empty(&dev->power.entry)) + list_move_tail(&dev->power.entry, &dpm_prepared_list); + put_device(dev); + } + mutex_unlock(&dpm_list_mtx); + return error; +} + +/** + * dpm_suspend_start - Prepare devices for PM transition and suspend them. + * @state: PM transition of the system being carried out. + * + * Prepare all non-sysdev devices for system PM transition and execute "suspend" + * callbacks for them. + */ +int dpm_suspend_start(pm_message_t state) +{ + int error; + + error = dpm_prepare(state); + if (!error) + error = dpm_suspend(state); + return error; +} +EXPORT_SYMBOL_GPL(dpm_suspend_start); + +void __suspend_report_result(const char *function, void *fn, int ret) +{ + if (ret) + printk(KERN_ERR "%s(): %pF returns %d\n", function, fn, ret); +} +EXPORT_SYMBOL_GPL(__suspend_report_result); + +/** + * device_pm_wait_for_dev - Wait for suspend/resume of a device to complete. + * @dev: Device to wait for. + * @subordinate: Device that needs to wait for @dev. + */ +int device_pm_wait_for_dev(struct device *subordinate, struct device *dev) +{ + dpm_wait(dev, subordinate->power.async_suspend); + return async_error; +} +EXPORT_SYMBOL_GPL(device_pm_wait_for_dev); diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c new file mode 100644 index 00000000..56a6899f --- /dev/null +++ b/drivers/base/power/opp.c @@ -0,0 +1,628 @@ +/* + * Generic OPP Interface + * + * Copyright (C) 2009-2010 Texas Instruments Incorporated. + * Nishanth Menon + * Romit Dasgupta + * Kevin Hilman + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/cpufreq.h> +#include <linux/list.h> +#include <linux/rculist.h> +#include <linux/rcupdate.h> +#include <linux/opp.h> + +/* + * Internal data structure organization with the OPP layer library is as + * follows: + * dev_opp_list (root) + * |- device 1 (represents voltage domain 1) + * | |- opp 1 (availability, freq, voltage) + * | |- opp 2 .. + * ... ... + * | `- opp n .. + * |- device 2 (represents the next voltage domain) + * ... + * `- device m (represents mth voltage domain) + * device 1, 2.. are represented by dev_opp structure while each opp + * is represented by the opp structure. + */ + +/** + * struct opp - Generic OPP description structure + * @node: opp list node. The nodes are maintained throughout the lifetime + * of boot. It is expected only an optimal set of OPPs are + * added to the library by the SoC framework. + * RCU usage: opp list is traversed with RCU locks. node + * modification is possible realtime, hence the modifications + * are protected by the dev_opp_list_lock for integrity. + * IMPORTANT: the opp nodes should be maintained in increasing + * order. + * @available: true/false - marks if this OPP as available or not + * @rate: Frequency in hertz + * @u_volt: Nominal voltage in microvolts corresponding to this OPP + * @dev_opp: points back to the device_opp struct this opp belongs to + * + * This structure stores the OPP information for a given device. + */ +struct opp { + struct list_head node; + + bool available; + unsigned long rate; + unsigned long u_volt; + + struct device_opp *dev_opp; +}; + +/** + * struct device_opp - Device opp structure + * @node: list node - contains the devices with OPPs that + * have been registered. Nodes once added are not modified in this + * list. + * RCU usage: nodes are not modified in the list of device_opp, + * however addition is possible and is secured by dev_opp_list_lock + * @dev: device pointer + * @opp_list: list of opps + * + * This is an internal data structure maintaining the link to opps attached to + * a device. This structure is not meant to be shared to users as it is + * meant for book keeping and private to OPP library + */ +struct device_opp { + struct list_head node; + + struct device *dev; + struct list_head opp_list; +}; + +/* + * The root of the list of all devices. All device_opp structures branch off + * from here, with each device_opp containing the list of opp it supports in + * various states of availability. + */ +static LIST_HEAD(dev_opp_list); +/* Lock to allow exclusive modification to the device and opp lists */ +static DEFINE_MUTEX(dev_opp_list_lock); + +/** + * find_device_opp() - find device_opp struct using device pointer + * @dev: device pointer used to lookup device OPPs + * + * Search list of device OPPs for one containing matching device. Does a RCU + * reader operation to grab the pointer needed. + * + * Returns pointer to 'struct device_opp' if found, otherwise -ENODEV or + * -EINVAL based on type of error. + * + * Locking: This function must be called under rcu_read_lock(). device_opp + * is a RCU protected pointer. This means that device_opp is valid as long + * as we are under RCU lock. + */ +static struct device_opp *find_device_opp(struct device *dev) +{ + struct device_opp *tmp_dev_opp, *dev_opp = ERR_PTR(-ENODEV); + + if (unlikely(IS_ERR_OR_NULL(dev))) { + pr_err("%s: Invalid parameters\n", __func__); + return ERR_PTR(-EINVAL); + } + + list_for_each_entry_rcu(tmp_dev_opp, &dev_opp_list, node) { + if (tmp_dev_opp->dev == dev) { + dev_opp = tmp_dev_opp; + break; + } + } + + return dev_opp; +} + +/** + * opp_get_voltage() - Gets the voltage corresponding to an available opp + * @opp: opp for which voltage has to be returned for + * + * Return voltage in micro volt corresponding to the opp, else + * return 0 + * + * Locking: This function must be called under rcu_read_lock(). opp is a rcu + * protected pointer. This means that opp which could have been fetched by + * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are + * under RCU lock. The pointer returned by the opp_find_freq family must be + * used in the same section as the usage of this function with the pointer + * prior to unlocking with rcu_read_unlock() to maintain the integrity of the + * pointer. + */ +unsigned long opp_get_voltage(struct opp *opp) +{ + struct opp *tmp_opp; + unsigned long v = 0; + + tmp_opp = rcu_dereference(opp); + if (unlikely(IS_ERR_OR_NULL(tmp_opp)) || !tmp_opp->available) + pr_err("%s: Invalid parameters\n", __func__); + else + v = tmp_opp->u_volt; + + return v; +} + +/** + * opp_get_freq() - Gets the frequency corresponding to an available opp + * @opp: opp for which frequency has to be returned for + * + * Return frequency in hertz corresponding to the opp, else + * return 0 + * + * Locking: This function must be called under rcu_read_lock(). opp is a rcu + * protected pointer. This means that opp which could have been fetched by + * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are + * under RCU lock. The pointer returned by the opp_find_freq family must be + * used in the same section as the usage of this function with the pointer + * prior to unlocking with rcu_read_unlock() to maintain the integrity of the + * pointer. + */ +unsigned long opp_get_freq(struct opp *opp) +{ + struct opp *tmp_opp; + unsigned long f = 0; + + tmp_opp = rcu_dereference(opp); + if (unlikely(IS_ERR_OR_NULL(tmp_opp)) || !tmp_opp->available) + pr_err("%s: Invalid parameters\n", __func__); + else + f = tmp_opp->rate; + + return f; +} + +/** + * opp_get_opp_count() - Get number of opps available in the opp list + * @dev: device for which we do this operation + * + * This function returns the number of available opps if there are any, + * else returns 0 if none or the corresponding error value. + * + * Locking: This function must be called under rcu_read_lock(). This function + * internally references two RCU protected structures: device_opp and opp which + * are safe as long as we are under a common RCU locked section. + */ +int opp_get_opp_count(struct device *dev) +{ + struct device_opp *dev_opp; + struct opp *temp_opp; + int count = 0; + + dev_opp = find_device_opp(dev); + if (IS_ERR(dev_opp)) { + int r = PTR_ERR(dev_opp); + dev_err(dev, "%s: device OPP not found (%d)\n", __func__, r); + return r; + } + + list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) { + if (temp_opp->available) + count++; + } + + return count; +} + +/** + * opp_find_freq_exact() - search for an exact frequency + * @dev: device for which we do this operation + * @freq: frequency to search for + * @available: true/false - match for available opp + * + * Searches for exact match in the opp list and returns pointer to the matching + * opp if found, else returns ERR_PTR in case of error and should be handled + * using IS_ERR. + * + * Note: available is a modifier for the search. if available=true, then the + * match is for exact matching frequency and is available in the stored OPP + * table. if false, the match is for exact frequency which is not available. + * + * This provides a mechanism to enable an opp which is not available currently + * or the opposite as well. + * + * Locking: This function must be called under rcu_read_lock(). opp is a rcu + * protected pointer. The reason for the same is that the opp pointer which is + * returned will remain valid for use with opp_get_{voltage, freq} only while + * under the locked area. The pointer returned must be used prior to unlocking + * with rcu_read_unlock() to maintain the integrity of the pointer. + */ +struct opp *opp_find_freq_exact(struct device *dev, unsigned long freq, + bool available) +{ + struct device_opp *dev_opp; + struct opp *temp_opp, *opp = ERR_PTR(-ENODEV); + + dev_opp = find_device_opp(dev); + if (IS_ERR(dev_opp)) { + int r = PTR_ERR(dev_opp); + dev_err(dev, "%s: device OPP not found (%d)\n", __func__, r); + return ERR_PTR(r); + } + + list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) { + if (temp_opp->available == available && + temp_opp->rate == freq) { + opp = temp_opp; + break; + } + } + + return opp; +} + +/** + * opp_find_freq_ceil() - Search for an rounded ceil freq + * @dev: device for which we do this operation + * @freq: Start frequency + * + * Search for the matching ceil *available* OPP from a starting freq + * for a device. + * + * Returns matching *opp and refreshes *freq accordingly, else returns + * ERR_PTR in case of error and should be handled using IS_ERR. + * + * Locking: This function must be called under rcu_read_lock(). opp is a rcu + * protected pointer. The reason for the same is that the opp pointer which is + * returned will remain valid for use with opp_get_{voltage, freq} only while + * under the locked area. The pointer returned must be used prior to unlocking + * with rcu_read_unlock() to maintain the integrity of the pointer. + */ +struct opp *opp_find_freq_ceil(struct device *dev, unsigned long *freq) +{ + struct device_opp *dev_opp; + struct opp *temp_opp, *opp = ERR_PTR(-ENODEV); + + if (!dev || !freq) { + dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); + return ERR_PTR(-EINVAL); + } + + dev_opp = find_device_opp(dev); + if (IS_ERR(dev_opp)) + return opp; + + list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) { + if (temp_opp->available && temp_opp->rate >= *freq) { + opp = temp_opp; + *freq = opp->rate; + break; + } + } + + return opp; +} + +/** + * opp_find_freq_floor() - Search for a rounded floor freq + * @dev: device for which we do this operation + * @freq: Start frequency + * + * Search for the matching floor *available* OPP from a starting freq + * for a device. + * + * Returns matching *opp and refreshes *freq accordingly, else returns + * ERR_PTR in case of error and should be handled using IS_ERR. + * + * Locking: This function must be called under rcu_read_lock(). opp is a rcu + * protected pointer. The reason for the same is that the opp pointer which is + * returned will remain valid for use with opp_get_{voltage, freq} only while + * under the locked area. The pointer returned must be used prior to unlocking + * with rcu_read_unlock() to maintain the integrity of the pointer. + */ +struct opp *opp_find_freq_floor(struct device *dev, unsigned long *freq) +{ + struct device_opp *dev_opp; + struct opp *temp_opp, *opp = ERR_PTR(-ENODEV); + + if (!dev || !freq) { + dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); + return ERR_PTR(-EINVAL); + } + + dev_opp = find_device_opp(dev); + if (IS_ERR(dev_opp)) + return opp; + + list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) { + if (temp_opp->available) { + /* go to the next node, before choosing prev */ + if (temp_opp->rate > *freq) + break; + else + opp = temp_opp; + } + } + if (!IS_ERR(opp)) + *freq = opp->rate; + + return opp; +} + +/** + * opp_add() - Add an OPP table from a table definitions + * @dev: device for which we do this operation + * @freq: Frequency in Hz for this OPP + * @u_volt: Voltage in uVolts for this OPP + * + * This function adds an opp definition to the opp list and returns status. + * The opp is made available by default and it can be controlled using + * opp_enable/disable functions. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function internally uses RCU updater strategy with mutex locks + * to keep the integrity of the internal data structures. Callers should ensure + * that this function is *NOT* called under RCU protection or in contexts where + * mutex cannot be locked. + */ +int opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) +{ + struct device_opp *dev_opp = NULL; + struct opp *opp, *new_opp; + struct list_head *head; + + /* allocate new OPP node */ + new_opp = kzalloc(sizeof(struct opp), GFP_KERNEL); + if (!new_opp) { + dev_warn(dev, "%s: Unable to create new OPP node\n", __func__); + return -ENOMEM; + } + + /* Hold our list modification lock here */ + mutex_lock(&dev_opp_list_lock); + + /* Check for existing list for 'dev' */ + dev_opp = find_device_opp(dev); + if (IS_ERR(dev_opp)) { + /* + * Allocate a new device OPP table. In the infrequent case + * where a new device is needed to be added, we pay this + * penalty. + */ + dev_opp = kzalloc(sizeof(struct device_opp), GFP_KERNEL); + if (!dev_opp) { + mutex_unlock(&dev_opp_list_lock); + kfree(new_opp); + dev_warn(dev, + "%s: Unable to create device OPP structure\n", + __func__); + return -ENOMEM; + } + + dev_opp->dev = dev; + INIT_LIST_HEAD(&dev_opp->opp_list); + + /* Secure the device list modification */ + list_add_rcu(&dev_opp->node, &dev_opp_list); + } + + /* populate the opp table */ + new_opp->dev_opp = dev_opp; + new_opp->rate = freq; + new_opp->u_volt = u_volt; + new_opp->available = true; + + /* Insert new OPP in order of increasing frequency */ + head = &dev_opp->opp_list; + list_for_each_entry_rcu(opp, &dev_opp->opp_list, node) { + if (new_opp->rate < opp->rate) + break; + else + head = &opp->node; + } + + list_add_rcu(&new_opp->node, head); + mutex_unlock(&dev_opp_list_lock); + + return 0; +} + +/** + * opp_set_availability() - helper to set the availability of an opp + * @dev: device for which we do this operation + * @freq: OPP frequency to modify availability + * @availability_req: availability status requested for this opp + * + * Set the availability of an OPP with an RCU operation, opp_{enable,disable} + * share a common logic which is isolated here. + * + * Returns -EINVAL for bad pointers, -ENOMEM if no memory available for the + * copy operation, returns 0 if no modifcation was done OR modification was + * successful. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function internally uses RCU updater strategy with mutex locks to + * keep the integrity of the internal data structures. Callers should ensure + * that this function is *NOT* called under RCU protection or in contexts where + * mutex locking or synchronize_rcu() blocking calls cannot be used. + */ +static int opp_set_availability(struct device *dev, unsigned long freq, + bool availability_req) +{ + struct device_opp *tmp_dev_opp, *dev_opp = NULL; + struct opp *new_opp, *tmp_opp, *opp = ERR_PTR(-ENODEV); + int r = 0; + + /* keep the node allocated */ + new_opp = kmalloc(sizeof(struct opp), GFP_KERNEL); + if (!new_opp) { + dev_warn(dev, "%s: Unable to create OPP\n", __func__); + return -ENOMEM; + } + + mutex_lock(&dev_opp_list_lock); + + /* Find the device_opp */ + list_for_each_entry(tmp_dev_opp, &dev_opp_list, node) { + if (dev == tmp_dev_opp->dev) { + dev_opp = tmp_dev_opp; + break; + } + } + if (IS_ERR(dev_opp)) { + r = PTR_ERR(dev_opp); + dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r); + goto unlock; + } + + /* Do we have the frequency? */ + list_for_each_entry(tmp_opp, &dev_opp->opp_list, node) { + if (tmp_opp->rate == freq) { + opp = tmp_opp; + break; + } + } + if (IS_ERR(opp)) { + r = PTR_ERR(opp); + goto unlock; + } + + /* Is update really needed? */ + if (opp->available == availability_req) + goto unlock; + /* copy the old data over */ + *new_opp = *opp; + + /* plug in new node */ + new_opp->available = availability_req; + + list_replace_rcu(&opp->node, &new_opp->node); + mutex_unlock(&dev_opp_list_lock); + synchronize_rcu(); + + /* clean up old opp */ + new_opp = opp; + goto out; + +unlock: + mutex_unlock(&dev_opp_list_lock); +out: + kfree(new_opp); + return r; +} + +/** + * opp_enable() - Enable a specific OPP + * @dev: device for which we do this operation + * @freq: OPP frequency to enable + * + * Enables a provided opp. If the operation is valid, this returns 0, else the + * corresponding error value. It is meant to be used for users an OPP available + * after being temporarily made unavailable with opp_disable. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function indirectly uses RCU and mutex locks to keep the + * integrity of the internal data structures. Callers should ensure that + * this function is *NOT* called under RCU protection or in contexts where + * mutex locking or synchronize_rcu() blocking calls cannot be used. + */ +int opp_enable(struct device *dev, unsigned long freq) +{ + return opp_set_availability(dev, freq, true); +} + +/** + * opp_disable() - Disable a specific OPP + * @dev: device for which we do this operation + * @freq: OPP frequency to disable + * + * Disables a provided opp. If the operation is valid, this returns + * 0, else the corresponding error value. It is meant to be a temporary + * control by users to make this OPP not available until the circumstances are + * right to make it available again (with a call to opp_enable). + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function indirectly uses RCU and mutex locks to keep the + * integrity of the internal data structures. Callers should ensure that + * this function is *NOT* called under RCU protection or in contexts where + * mutex locking or synchronize_rcu() blocking calls cannot be used. + */ +int opp_disable(struct device *dev, unsigned long freq) +{ + return opp_set_availability(dev, freq, false); +} + +#ifdef CONFIG_CPU_FREQ +/** + * opp_init_cpufreq_table() - create a cpufreq table for a device + * @dev: device for which we do this operation + * @table: Cpufreq table returned back to caller + * + * Generate a cpufreq table for a provided device- this assumes that the + * opp list is already initialized and ready for usage. + * + * This function allocates required memory for the cpufreq table. It is + * expected that the caller does the required maintenance such as freeing + * the table as required. + * + * Returns -EINVAL for bad pointers, -ENODEV if the device is not found, -ENOMEM + * if no memory available for the operation (table is not populated), returns 0 + * if successful and table is populated. + * + * WARNING: It is important for the callers to ensure refreshing their copy of + * the table if any of the mentioned functions have been invoked in the interim. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * To simplify the logic, we pretend we are updater and hold relevant mutex here + * Callers should ensure that this function is *NOT* called under RCU protection + * or in contexts where mutex locking cannot be used. + */ +int opp_init_cpufreq_table(struct device *dev, + struct cpufreq_frequency_table **table) +{ + struct device_opp *dev_opp; + struct opp *opp; + struct cpufreq_frequency_table *freq_table; + int i = 0; + + /* Pretend as if I am an updater */ + mutex_lock(&dev_opp_list_lock); + + dev_opp = find_device_opp(dev); + if (IS_ERR(dev_opp)) { + int r = PTR_ERR(dev_opp); + mutex_unlock(&dev_opp_list_lock); + dev_err(dev, "%s: Device OPP not found (%d)\n", __func__, r); + return r; + } + + freq_table = kzalloc(sizeof(struct cpufreq_frequency_table) * + (opp_get_opp_count(dev) + 1), GFP_KERNEL); + if (!freq_table) { + mutex_unlock(&dev_opp_list_lock); + dev_warn(dev, "%s: Unable to allocate frequency table\n", + __func__); + return -ENOMEM; + } + + list_for_each_entry(opp, &dev_opp->opp_list, node) { + if (opp->available) { + freq_table[i].index = i; + freq_table[i].frequency = opp->rate / 1000; + i++; + } + } + mutex_unlock(&dev_opp_list_lock); + + freq_table[i].index = i; + freq_table[i].frequency = CPUFREQ_TABLE_END; + + *table = &freq_table[0]; + + return 0; +} +#endif /* CONFIG_CPU_FREQ */ diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h new file mode 100644 index 00000000..51b585a4 --- /dev/null +++ b/drivers/base/power/power.h @@ -0,0 +1,79 @@ +#ifdef CONFIG_PM_RUNTIME + +extern void pm_runtime_init(struct device *dev); +extern void pm_runtime_remove(struct device *dev); + +#else /* !CONFIG_PM_RUNTIME */ + +static inline void pm_runtime_init(struct device *dev) {} +static inline void pm_runtime_remove(struct device *dev) {} + +#endif /* !CONFIG_PM_RUNTIME */ + +#ifdef CONFIG_SUSPEND_DEVICE_TIME_DEBUG +extern int device_suspend_time_threshold; +#endif + +#ifdef CONFIG_PM_SLEEP + +/* kernel/power/main.c */ +extern int pm_async_enabled; + +/* drivers/base/power/main.c */ +extern struct list_head dpm_list; /* The active device list */ + +static inline struct device *to_device(struct list_head *entry) +{ + return container_of(entry, struct device, power.entry); +} + +extern void device_pm_init(struct device *dev); +extern void device_pm_add(struct device *); +extern void device_pm_remove(struct device *); +extern void device_pm_move_before(struct device *, struct device *); +extern void device_pm_move_after(struct device *, struct device *); +extern void device_pm_move_last(struct device *); + +#else /* !CONFIG_PM_SLEEP */ + +static inline void device_pm_init(struct device *dev) +{ + spin_lock_init(&dev->power.lock); + pm_runtime_init(dev); +} + +static inline void device_pm_remove(struct device *dev) +{ + pm_runtime_remove(dev); +} + +static inline void device_pm_add(struct device *dev) {} +static inline void device_pm_move_before(struct device *deva, + struct device *devb) {} +static inline void device_pm_move_after(struct device *deva, + struct device *devb) {} +static inline void device_pm_move_last(struct device *dev) {} + +#endif /* !CONFIG_PM_SLEEP */ + +#ifdef CONFIG_PM + +/* + * sysfs.c + */ + +extern int dpm_sysfs_add(struct device *dev); +extern void dpm_sysfs_remove(struct device *dev); +extern void rpm_sysfs_remove(struct device *dev); +extern int wakeup_sysfs_add(struct device *dev); +extern void wakeup_sysfs_remove(struct device *dev); + +#else /* CONFIG_PM */ + +static inline int dpm_sysfs_add(struct device *dev) { return 0; } +static inline void dpm_sysfs_remove(struct device *dev) {} +static inline void rpm_sysfs_remove(struct device *dev) {} +static inline int wakeup_sysfs_add(struct device *dev) { return 0; } +static inline void wakeup_sysfs_remove(struct device *dev) {} + +#endif diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c new file mode 100644 index 00000000..184cf54f --- /dev/null +++ b/drivers/base/power/runtime.c @@ -0,0 +1,1263 @@ +/* + * drivers/base/power/runtime.c - Helper functions for device run-time PM + * + * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + * Copyright (C) 2010 Alan Stern <stern@rowland.harvard.edu> + * + * This file is released under the GPLv2. + */ + +#include <linux/sched.h> +#include <linux/pm_runtime.h> +#include "power.h" + +static int rpm_resume(struct device *dev, int rpmflags); +static int rpm_suspend(struct device *dev, int rpmflags); + +/** + * update_pm_runtime_accounting - Update the time accounting of power states + * @dev: Device to update the accounting for + * + * In order to be able to have time accounting of the various power states + * (as used by programs such as PowerTOP to show the effectiveness of runtime + * PM), we need to track the time spent in each state. + * update_pm_runtime_accounting must be called each time before the + * runtime_status field is updated, to account the time in the old state + * correctly. + */ +void update_pm_runtime_accounting(struct device *dev) +{ + unsigned long now = jiffies; + int delta; + + delta = now - dev->power.accounting_timestamp; + + if (delta < 0) + delta = 0; + + dev->power.accounting_timestamp = now; + + if (dev->power.disable_depth > 0) + return; + + if (dev->power.runtime_status == RPM_SUSPENDED) + dev->power.suspended_jiffies += delta; + else + dev->power.active_jiffies += delta; +} + +static void __update_runtime_status(struct device *dev, enum rpm_status status) +{ + update_pm_runtime_accounting(dev); + dev->power.runtime_status = status; +} + +/** + * pm_runtime_deactivate_timer - Deactivate given device's suspend timer. + * @dev: Device to handle. + */ +static void pm_runtime_deactivate_timer(struct device *dev) +{ + if (dev->power.timer_expires > 0) { + del_timer(&dev->power.suspend_timer); + dev->power.timer_expires = 0; + } +} + +/** + * pm_runtime_cancel_pending - Deactivate suspend timer and cancel requests. + * @dev: Device to handle. + */ +static void pm_runtime_cancel_pending(struct device *dev) +{ + pm_runtime_deactivate_timer(dev); + /* + * In case there's a request pending, make sure its work function will + * return without doing anything. + */ + dev->power.request = RPM_REQ_NONE; +} + +/* + * pm_runtime_autosuspend_expiration - Get a device's autosuspend-delay expiration time. + * @dev: Device to handle. + * + * Compute the autosuspend-delay expiration time based on the device's + * power.last_busy time. If the delay has already expired or is disabled + * (negative) or the power.use_autosuspend flag isn't set, return 0. + * Otherwise return the expiration time in jiffies (adjusted to be nonzero). + * + * This function may be called either with or without dev->power.lock held. + * Either way it can be racy, since power.last_busy may be updated at any time. + */ +unsigned long pm_runtime_autosuspend_expiration(struct device *dev) +{ + int autosuspend_delay; + long elapsed; + unsigned long last_busy; + unsigned long expires = 0; + + if (!dev->power.use_autosuspend) + goto out; + + autosuspend_delay = ACCESS_ONCE(dev->power.autosuspend_delay); + if (autosuspend_delay < 0) + goto out; + + last_busy = ACCESS_ONCE(dev->power.last_busy); + elapsed = jiffies - last_busy; + if (elapsed < 0) + goto out; /* jiffies has wrapped around. */ + + /* + * If the autosuspend_delay is >= 1 second, align the timer by rounding + * up to the nearest second. + */ + expires = last_busy + msecs_to_jiffies(autosuspend_delay); + if (autosuspend_delay >= 1000) + expires = round_jiffies(expires); + expires += !expires; + if (elapsed >= expires - last_busy) + expires = 0; /* Already expired. */ + + out: + return expires; +} +EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration); + +/** + * rpm_check_suspend_allowed - Test whether a device may be suspended. + * @dev: Device to test. + */ +static int rpm_check_suspend_allowed(struct device *dev) +{ + int retval = 0; + + if (dev->power.runtime_error) + retval = -EINVAL; + else if (atomic_read(&dev->power.usage_count) > 0 + || dev->power.disable_depth > 0) + retval = -EAGAIN; + else if (!pm_children_suspended(dev)) + retval = -EBUSY; + + /* Pending resume requests take precedence over suspends. */ + else if ((dev->power.deferred_resume + && dev->power.runtime_status == RPM_SUSPENDING) + || (dev->power.request_pending + && dev->power.request == RPM_REQ_RESUME)) + retval = -EAGAIN; + else if (dev->power.runtime_status == RPM_SUSPENDED) + retval = 1; + + return retval; +} + +/** + * rpm_idle - Notify device bus type if the device can be suspended. + * @dev: Device to notify the bus type about. + * @rpmflags: Flag bits. + * + * Check if the device's run-time PM status allows it to be suspended. If + * another idle notification has been started earlier, return immediately. If + * the RPM_ASYNC flag is set then queue an idle-notification request; otherwise + * run the ->runtime_idle() callback directly. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static int rpm_idle(struct device *dev, int rpmflags) +{ + int (*callback)(struct device *); + int retval; + + retval = rpm_check_suspend_allowed(dev); + if (retval < 0) + ; /* Conditions are wrong. */ + + /* Idle notifications are allowed only in the RPM_ACTIVE state. */ + else if (dev->power.runtime_status != RPM_ACTIVE) + retval = -EAGAIN; + + /* + * Any pending request other than an idle notification takes + * precedence over us, except that the timer may be running. + */ + else if (dev->power.request_pending && + dev->power.request > RPM_REQ_IDLE) + retval = -EAGAIN; + + /* Act as though RPM_NOWAIT is always set. */ + else if (dev->power.idle_notification) + retval = -EINPROGRESS; + if (retval) + goto out; + + /* Pending requests need to be canceled. */ + dev->power.request = RPM_REQ_NONE; + + if (dev->power.no_callbacks) { + /* Assume ->runtime_idle() callback would have suspended. */ + retval = rpm_suspend(dev, rpmflags); + goto out; + } + + /* Carry out an asynchronous or a synchronous idle notification. */ + if (rpmflags & RPM_ASYNC) { + dev->power.request = RPM_REQ_IDLE; + if (!dev->power.request_pending) { + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); + } + goto out; + } + + dev->power.idle_notification = true; + + if (dev->pwr_domain) + callback = dev->pwr_domain->ops.runtime_idle; + else if (dev->type && dev->type->pm) + callback = dev->type->pm->runtime_idle; + else if (dev->class && dev->class->pm) + callback = dev->class->pm->runtime_idle; + else if (dev->bus && dev->bus->pm) + callback = dev->bus->pm->runtime_idle; + else + callback = NULL; + + if (callback) { + spin_unlock_irq(&dev->power.lock); + + callback(dev); + + spin_lock_irq(&dev->power.lock); + } + + dev->power.idle_notification = false; + wake_up_all(&dev->power.wait_queue); + + out: + return retval; +} + +/** + * rpm_callback - Run a given runtime PM callback for a given device. + * @cb: Runtime PM callback to run. + * @dev: Device to run the callback for. + */ +static int rpm_callback(int (*cb)(struct device *), struct device *dev) + __releases(&dev->power.lock) __acquires(&dev->power.lock) +{ + int retval; + + if (!cb) + return -ENOSYS; + + if (dev->power.irq_safe) { + retval = cb(dev); + } else { + spin_unlock_irq(&dev->power.lock); + + retval = cb(dev); + + spin_lock_irq(&dev->power.lock); + } + dev->power.runtime_error = retval; + return retval; +} + +/** + * rpm_suspend - Carry out run-time suspend of given device. + * @dev: Device to suspend. + * @rpmflags: Flag bits. + * + * Check if the device's run-time PM status allows it to be suspended. If + * another suspend has been started earlier, either return immediately or wait + * for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC flags. Cancel a + * pending idle notification. If the RPM_ASYNC flag is set then queue a + * suspend request; otherwise run the ->runtime_suspend() callback directly. + * If a deferred resume was requested while the callback was running then carry + * it out; otherwise send an idle notification for the device (if the suspend + * failed) or for its parent (if the suspend succeeded). + * If ->runtime_suspend failed with -EAGAIN or -EBUSY, and if the RPM_AUTO + * flag is set and the next autosuspend-delay expiration time is in the + * future, schedule another autosuspend attempt. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static int rpm_suspend(struct device *dev, int rpmflags) + __releases(&dev->power.lock) __acquires(&dev->power.lock) +{ + int (*callback)(struct device *); + struct device *parent = NULL; + int retval; + + dev_dbg(dev, "%s flags 0x%x\n", __func__, rpmflags); + + repeat: + retval = rpm_check_suspend_allowed(dev); + + if (retval < 0) + ; /* Conditions are wrong. */ + + /* Synchronous suspends are not allowed in the RPM_RESUMING state. */ + else if (dev->power.runtime_status == RPM_RESUMING && + !(rpmflags & RPM_ASYNC)) + retval = -EAGAIN; + if (retval) + goto out; + + /* If the autosuspend_delay time hasn't expired yet, reschedule. */ + if ((rpmflags & RPM_AUTO) + && dev->power.runtime_status != RPM_SUSPENDING) { + unsigned long expires = pm_runtime_autosuspend_expiration(dev); + + if (expires != 0) { + /* Pending requests need to be canceled. */ + dev->power.request = RPM_REQ_NONE; + + /* + * Optimization: If the timer is already running and is + * set to expire at or before the autosuspend delay, + * avoid the overhead of resetting it. Just let it + * expire; pm_suspend_timer_fn() will take care of the + * rest. + */ + if (!(dev->power.timer_expires && time_before_eq( + dev->power.timer_expires, expires))) { + dev->power.timer_expires = expires; + mod_timer(&dev->power.suspend_timer, expires); + } + dev->power.timer_autosuspends = 1; + goto out; + } + } + + /* Other scheduled or pending requests need to be canceled. */ + pm_runtime_cancel_pending(dev); + + if (dev->power.runtime_status == RPM_SUSPENDING) { + DEFINE_WAIT(wait); + + if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { + retval = -EINPROGRESS; + goto out; + } + + /* Wait for the other suspend running in parallel with us. */ + for (;;) { + prepare_to_wait(&dev->power.wait_queue, &wait, + TASK_UNINTERRUPTIBLE); + if (dev->power.runtime_status != RPM_SUSPENDING) + break; + + spin_unlock_irq(&dev->power.lock); + + schedule(); + + spin_lock_irq(&dev->power.lock); + } + finish_wait(&dev->power.wait_queue, &wait); + goto repeat; + } + + dev->power.deferred_resume = false; + if (dev->power.no_callbacks) + goto no_callback; /* Assume success. */ + + /* Carry out an asynchronous or a synchronous suspend. */ + if (rpmflags & RPM_ASYNC) { + dev->power.request = (rpmflags & RPM_AUTO) ? + RPM_REQ_AUTOSUSPEND : RPM_REQ_SUSPEND; + if (!dev->power.request_pending) { + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); + } + goto out; + } + + __update_runtime_status(dev, RPM_SUSPENDING); + + if (dev->pwr_domain) + callback = dev->pwr_domain->ops.runtime_suspend; + else if (dev->type && dev->type->pm) + callback = dev->type->pm->runtime_suspend; + else if (dev->class && dev->class->pm) + callback = dev->class->pm->runtime_suspend; + else if (dev->bus && dev->bus->pm) + callback = dev->bus->pm->runtime_suspend; + else + callback = NULL; + + retval = rpm_callback(callback, dev); + if (retval) { + __update_runtime_status(dev, RPM_ACTIVE); + dev->power.deferred_resume = 0; + if (retval == -EAGAIN || retval == -EBUSY) { + dev->power.runtime_error = 0; + + /* + * If the callback routine failed an autosuspend, and + * if the last_busy time has been updated so that there + * is a new autosuspend expiration time, automatically + * reschedule another autosuspend. + */ + if ((rpmflags & RPM_AUTO) && + pm_runtime_autosuspend_expiration(dev) != 0) + goto repeat; + } else { + pm_runtime_cancel_pending(dev); + } + } else { + no_callback: + __update_runtime_status(dev, RPM_SUSPENDED); + pm_runtime_deactivate_timer(dev); + + if (dev->parent) { + parent = dev->parent; + atomic_add_unless(&parent->power.child_count, -1, 0); + } + } + wake_up_all(&dev->power.wait_queue); + + if (dev->power.deferred_resume) { + rpm_resume(dev, 0); + retval = -EAGAIN; + goto out; + } + + /* Maybe the parent is now able to suspend. */ + if (parent && !parent->power.ignore_children && !dev->power.irq_safe) { + spin_unlock(&dev->power.lock); + + spin_lock(&parent->power.lock); + rpm_idle(parent, RPM_ASYNC); + spin_unlock(&parent->power.lock); + + spin_lock(&dev->power.lock); + } + + out: + dev_dbg(dev, "%s returns %d\n", __func__, retval); + + return retval; +} + +/** + * rpm_resume - Carry out run-time resume of given device. + * @dev: Device to resume. + * @rpmflags: Flag bits. + * + * Check if the device's run-time PM status allows it to be resumed. Cancel + * any scheduled or pending requests. If another resume has been started + * earlier, either return immediately or wait for it to finish, depending on the + * RPM_NOWAIT and RPM_ASYNC flags. Similarly, if there's a suspend running in + * parallel with this function, either tell the other process to resume after + * suspending (deferred_resume) or wait for it to finish. If the RPM_ASYNC + * flag is set then queue a resume request; otherwise run the + * ->runtime_resume() callback directly. Queue an idle notification for the + * device if the resume succeeded. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static int rpm_resume(struct device *dev, int rpmflags) + __releases(&dev->power.lock) __acquires(&dev->power.lock) +{ + int (*callback)(struct device *); + struct device *parent = NULL; + int retval = 0; + + dev_dbg(dev, "%s flags 0x%x\n", __func__, rpmflags); + + repeat: + if (dev->power.runtime_error) + retval = -EINVAL; + else if (dev->power.disable_depth > 0) + retval = -EAGAIN; + if (retval) + goto out; + + /* + * Other scheduled or pending requests need to be canceled. Small + * optimization: If an autosuspend timer is running, leave it running + * rather than cancelling it now only to restart it again in the near + * future. + */ + dev->power.request = RPM_REQ_NONE; + if (!dev->power.timer_autosuspends) + pm_runtime_deactivate_timer(dev); + + if (dev->power.runtime_status == RPM_ACTIVE) { + retval = 1; + goto out; + } + + if (dev->power.runtime_status == RPM_RESUMING + || dev->power.runtime_status == RPM_SUSPENDING) { + DEFINE_WAIT(wait); + + if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { + if (dev->power.runtime_status == RPM_SUSPENDING) + dev->power.deferred_resume = true; + else + retval = -EINPROGRESS; + goto out; + } + + /* Wait for the operation carried out in parallel with us. */ + for (;;) { + prepare_to_wait(&dev->power.wait_queue, &wait, + TASK_UNINTERRUPTIBLE); + if (dev->power.runtime_status != RPM_RESUMING + && dev->power.runtime_status != RPM_SUSPENDING) + break; + + spin_unlock_irq(&dev->power.lock); + + schedule(); + + spin_lock_irq(&dev->power.lock); + } + finish_wait(&dev->power.wait_queue, &wait); + goto repeat; + } + + /* + * See if we can skip waking up the parent. This is safe only if + * power.no_callbacks is set, because otherwise we don't know whether + * the resume will actually succeed. + */ + if (dev->power.no_callbacks && !parent && dev->parent) { + spin_lock_nested(&dev->parent->power.lock, SINGLE_DEPTH_NESTING); + if (dev->parent->power.disable_depth > 0 + || dev->parent->power.ignore_children + || dev->parent->power.runtime_status == RPM_ACTIVE) { + atomic_inc(&dev->parent->power.child_count); + spin_unlock(&dev->parent->power.lock); + goto no_callback; /* Assume success. */ + } + spin_unlock(&dev->parent->power.lock); + } + + /* Carry out an asynchronous or a synchronous resume. */ + if (rpmflags & RPM_ASYNC) { + dev->power.request = RPM_REQ_RESUME; + if (!dev->power.request_pending) { + dev->power.request_pending = true; + queue_work(pm_wq, &dev->power.work); + } + retval = 0; + goto out; + } + + if (!parent && dev->parent) { + /* + * Increment the parent's usage counter and resume it if + * necessary. Not needed if dev is irq-safe; then the + * parent is permanently resumed. + */ + parent = dev->parent; + if (dev->power.irq_safe) + goto skip_parent; + spin_unlock(&dev->power.lock); + + pm_runtime_get_noresume(parent); + + spin_lock(&parent->power.lock); + /* + * We can resume if the parent's run-time PM is disabled or it + * is set to ignore children. + */ + if (!parent->power.disable_depth + && !parent->power.ignore_children) { + rpm_resume(parent, 0); + if (parent->power.runtime_status != RPM_ACTIVE) + retval = -EBUSY; + } + spin_unlock(&parent->power.lock); + + spin_lock(&dev->power.lock); + if (retval) + goto out; + goto repeat; + } + skip_parent: + + if (dev->power.no_callbacks) + goto no_callback; /* Assume success. */ + + __update_runtime_status(dev, RPM_RESUMING); + + if (dev->pwr_domain) + callback = dev->pwr_domain->ops.runtime_resume; + else if (dev->type && dev->type->pm) + callback = dev->type->pm->runtime_resume; + else if (dev->class && dev->class->pm) + callback = dev->class->pm->runtime_resume; + else if (dev->bus && dev->bus->pm) + callback = dev->bus->pm->runtime_resume; + else + callback = NULL; + + retval = rpm_callback(callback, dev); + if (retval) { + __update_runtime_status(dev, RPM_SUSPENDED); + pm_runtime_cancel_pending(dev); + } else { + no_callback: + __update_runtime_status(dev, RPM_ACTIVE); + if (parent) + atomic_inc(&parent->power.child_count); + } + wake_up_all(&dev->power.wait_queue); + + if (!retval) + rpm_idle(dev, RPM_ASYNC); + + out: + if (parent && !dev->power.irq_safe) { + spin_unlock_irq(&dev->power.lock); + + pm_runtime_put(parent); + + spin_lock_irq(&dev->power.lock); + } + + dev_dbg(dev, "%s returns %d\n", __func__, retval); + + return retval; +} + +/** + * pm_runtime_work - Universal run-time PM work function. + * @work: Work structure used for scheduling the execution of this function. + * + * Use @work to get the device object the work is to be done for, determine what + * is to be done and execute the appropriate run-time PM function. + */ +static void pm_runtime_work(struct work_struct *work) +{ + struct device *dev = container_of(work, struct device, power.work); + enum rpm_request req; + + spin_lock_irq(&dev->power.lock); + + if (!dev->power.request_pending) + goto out; + + req = dev->power.request; + dev->power.request = RPM_REQ_NONE; + dev->power.request_pending = false; + + switch (req) { + case RPM_REQ_NONE: + break; + case RPM_REQ_IDLE: + rpm_idle(dev, RPM_NOWAIT); + break; + case RPM_REQ_SUSPEND: + rpm_suspend(dev, RPM_NOWAIT); + break; + case RPM_REQ_AUTOSUSPEND: + rpm_suspend(dev, RPM_NOWAIT | RPM_AUTO); + break; + case RPM_REQ_RESUME: + rpm_resume(dev, RPM_NOWAIT); + break; + } + + out: + spin_unlock_irq(&dev->power.lock); +} + +/** + * pm_suspend_timer_fn - Timer function for pm_schedule_suspend(). + * @data: Device pointer passed by pm_schedule_suspend(). + * + * Check if the time is right and queue a suspend request. + */ +static void pm_suspend_timer_fn(unsigned long data) +{ + struct device *dev = (struct device *)data; + unsigned long flags; + unsigned long expires; + + spin_lock_irqsave(&dev->power.lock, flags); + + expires = dev->power.timer_expires; + /* If 'expire' is after 'jiffies' we've been called too early. */ + if (expires > 0 && !time_after(expires, jiffies)) { + dev->power.timer_expires = 0; + rpm_suspend(dev, dev->power.timer_autosuspends ? + (RPM_ASYNC | RPM_AUTO) : RPM_ASYNC); + } + + spin_unlock_irqrestore(&dev->power.lock, flags); +} + +/** + * pm_schedule_suspend - Set up a timer to submit a suspend request in future. + * @dev: Device to suspend. + * @delay: Time to wait before submitting a suspend request, in milliseconds. + */ +int pm_schedule_suspend(struct device *dev, unsigned int delay) +{ + unsigned long flags; + int retval; + + spin_lock_irqsave(&dev->power.lock, flags); + + if (!delay) { + retval = rpm_suspend(dev, RPM_ASYNC); + goto out; + } + + retval = rpm_check_suspend_allowed(dev); + if (retval) + goto out; + + /* Other scheduled or pending requests need to be canceled. */ + pm_runtime_cancel_pending(dev); + + dev->power.timer_expires = jiffies + msecs_to_jiffies(delay); + dev->power.timer_expires += !dev->power.timer_expires; + dev->power.timer_autosuspends = 0; + mod_timer(&dev->power.suspend_timer, dev->power.timer_expires); + + out: + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_schedule_suspend); + +/** + * __pm_runtime_idle - Entry point for run-time idle operations. + * @dev: Device to send idle notification for. + * @rpmflags: Flag bits. + * + * If the RPM_GET_PUT flag is set, decrement the device's usage count and + * return immediately if it is larger than zero. Then carry out an idle + * notification, either synchronous or asynchronous. + * + * This routine may be called in atomic context if the RPM_ASYNC flag is set. + */ +int __pm_runtime_idle(struct device *dev, int rpmflags) +{ + unsigned long flags; + int retval; + + might_sleep_if(!(rpmflags & RPM_ASYNC)); + + if (rpmflags & RPM_GET_PUT) { + if (!atomic_dec_and_test(&dev->power.usage_count)) + return 0; + } + + spin_lock_irqsave(&dev->power.lock, flags); + retval = rpm_idle(dev, rpmflags); + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} +EXPORT_SYMBOL_GPL(__pm_runtime_idle); + +/** + * __pm_runtime_suspend - Entry point for run-time put/suspend operations. + * @dev: Device to suspend. + * @rpmflags: Flag bits. + * + * If the RPM_GET_PUT flag is set, decrement the device's usage count and + * return immediately if it is larger than zero. Then carry out a suspend, + * either synchronous or asynchronous. + * + * This routine may be called in atomic context if the RPM_ASYNC flag is set. + */ +int __pm_runtime_suspend(struct device *dev, int rpmflags) +{ + unsigned long flags; + int retval; + + might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); + + if (rpmflags & RPM_GET_PUT) { + if (!atomic_dec_and_test(&dev->power.usage_count)) + return 0; + } + + spin_lock_irqsave(&dev->power.lock, flags); + retval = rpm_suspend(dev, rpmflags); + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} +EXPORT_SYMBOL_GPL(__pm_runtime_suspend); + +/** + * __pm_runtime_resume - Entry point for run-time resume operations. + * @dev: Device to resume. + * @rpmflags: Flag bits. + * + * If the RPM_GET_PUT flag is set, increment the device's usage count. Then + * carry out a resume, either synchronous or asynchronous. + * + * This routine may be called in atomic context if the RPM_ASYNC flag is set. + */ +int __pm_runtime_resume(struct device *dev, int rpmflags) +{ + unsigned long flags; + int retval; + + might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); + + if (rpmflags & RPM_GET_PUT) + atomic_inc(&dev->power.usage_count); + + spin_lock_irqsave(&dev->power.lock, flags); + retval = rpm_resume(dev, rpmflags); + spin_unlock_irqrestore(&dev->power.lock, flags); + + return retval; +} +EXPORT_SYMBOL_GPL(__pm_runtime_resume); + +/** + * __pm_runtime_set_status - Set run-time PM status of a device. + * @dev: Device to handle. + * @status: New run-time PM status of the device. + * + * If run-time PM of the device is disabled or its power.runtime_error field is + * different from zero, the status may be changed either to RPM_ACTIVE, or to + * RPM_SUSPENDED, as long as that reflects the actual state of the device. + * However, if the device has a parent and the parent is not active, and the + * parent's power.ignore_children flag is unset, the device's status cannot be + * set to RPM_ACTIVE, so -EBUSY is returned in that case. + * + * If successful, __pm_runtime_set_status() clears the power.runtime_error field + * and the device parent's counter of unsuspended children is modified to + * reflect the new status. If the new status is RPM_SUSPENDED, an idle + * notification request for the parent is submitted. + */ +int __pm_runtime_set_status(struct device *dev, unsigned int status) +{ + struct device *parent = dev->parent; + unsigned long flags; + bool notify_parent = false; + int error = 0; + + if (status != RPM_ACTIVE && status != RPM_SUSPENDED) + return -EINVAL; + + spin_lock_irqsave(&dev->power.lock, flags); + + if (!dev->power.runtime_error && !dev->power.disable_depth) { + error = -EAGAIN; + goto out; + } + + if (dev->power.runtime_status == status) + goto out_set; + + if (status == RPM_SUSPENDED) { + /* It always is possible to set the status to 'suspended'. */ + if (parent) { + atomic_add_unless(&parent->power.child_count, -1, 0); + notify_parent = !parent->power.ignore_children; + } + goto out_set; + } + + if (parent) { + spin_lock_nested(&parent->power.lock, SINGLE_DEPTH_NESTING); + + /* + * It is invalid to put an active child under a parent that is + * not active, has run-time PM enabled and the + * 'power.ignore_children' flag unset. + */ + if (!parent->power.disable_depth + && !parent->power.ignore_children + && parent->power.runtime_status != RPM_ACTIVE) + error = -EBUSY; + else if (dev->power.runtime_status == RPM_SUSPENDED) + atomic_inc(&parent->power.child_count); + + spin_unlock(&parent->power.lock); + + if (error) + goto out; + } + + out_set: + __update_runtime_status(dev, status); + dev->power.runtime_error = 0; + out: + spin_unlock_irqrestore(&dev->power.lock, flags); + + if (notify_parent) + pm_request_idle(parent); + + return error; +} +EXPORT_SYMBOL_GPL(__pm_runtime_set_status); + +/** + * __pm_runtime_barrier - Cancel pending requests and wait for completions. + * @dev: Device to handle. + * + * Flush all pending requests for the device from pm_wq and wait for all + * run-time PM operations involving the device in progress to complete. + * + * Should be called under dev->power.lock with interrupts disabled. + */ +static void __pm_runtime_barrier(struct device *dev) +{ + pm_runtime_deactivate_timer(dev); + + if (dev->power.request_pending) { + dev->power.request = RPM_REQ_NONE; + spin_unlock_irq(&dev->power.lock); + + cancel_work_sync(&dev->power.work); + + spin_lock_irq(&dev->power.lock); + dev->power.request_pending = false; + } + + if (dev->power.runtime_status == RPM_SUSPENDING + || dev->power.runtime_status == RPM_RESUMING + || dev->power.idle_notification) { + DEFINE_WAIT(wait); + + /* Suspend, wake-up or idle notification in progress. */ + for (;;) { + prepare_to_wait(&dev->power.wait_queue, &wait, + TASK_UNINTERRUPTIBLE); + if (dev->power.runtime_status != RPM_SUSPENDING + && dev->power.runtime_status != RPM_RESUMING + && !dev->power.idle_notification) + break; + spin_unlock_irq(&dev->power.lock); + + schedule(); + + spin_lock_irq(&dev->power.lock); + } + finish_wait(&dev->power.wait_queue, &wait); + } +} + +/** + * pm_runtime_barrier - Flush pending requests and wait for completions. + * @dev: Device to handle. + * + * Prevent the device from being suspended by incrementing its usage counter and + * if there's a pending resume request for the device, wake the device up. + * Next, make sure that all pending requests for the device have been flushed + * from pm_wq and wait for all run-time PM operations involving the device in + * progress to complete. + * + * Return value: + * 1, if there was a resume request pending and the device had to be woken up, + * 0, otherwise + */ +int pm_runtime_barrier(struct device *dev) +{ + int retval = 0; + + pm_runtime_get_noresume(dev); + spin_lock_irq(&dev->power.lock); + + if (dev->power.request_pending + && dev->power.request == RPM_REQ_RESUME) { + rpm_resume(dev, 0); + retval = 1; + } + + __pm_runtime_barrier(dev); + + spin_unlock_irq(&dev->power.lock); + pm_runtime_put_noidle(dev); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_runtime_barrier); + +/** + * __pm_runtime_disable - Disable run-time PM of a device. + * @dev: Device to handle. + * @check_resume: If set, check if there's a resume request for the device. + * + * Increment power.disable_depth for the device and if was zero previously, + * cancel all pending run-time PM requests for the device and wait for all + * operations in progress to complete. The device can be either active or + * suspended after its run-time PM has been disabled. + * + * If @check_resume is set and there's a resume request pending when + * __pm_runtime_disable() is called and power.disable_depth is zero, the + * function will wake up the device before disabling its run-time PM. + */ +void __pm_runtime_disable(struct device *dev, bool check_resume) +{ + might_sleep(); + spin_lock_irq(&dev->power.lock); + + if (dev->power.disable_depth > 0) { + dev->power.disable_depth++; + goto out; + } + + /* + * Wake up the device if there's a resume request pending, because that + * means there probably is some I/O to process and disabling run-time PM + * shouldn't prevent the device from processing the I/O. + */ + if (check_resume && dev->power.request_pending + && dev->power.request == RPM_REQ_RESUME) { + /* + * Prevent suspends and idle notifications from being carried + * out after we have woken up the device. + */ + pm_runtime_get_noresume(dev); + + rpm_resume(dev, 0); + + pm_runtime_put_noidle(dev); + } + + if (!dev->power.disable_depth++) + __pm_runtime_barrier(dev); + + out: + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(__pm_runtime_disable); + +/** + * pm_runtime_enable - Enable run-time PM of a device. + * @dev: Device to handle. + */ +void pm_runtime_enable(struct device *dev) +{ + unsigned long flags; + + spin_lock_irqsave(&dev->power.lock, flags); + + if (dev->power.disable_depth > 0) + dev->power.disable_depth--; + else + dev_warn(dev, "Unbalanced %s!\n", __func__); + + spin_unlock_irqrestore(&dev->power.lock, flags); +} +EXPORT_SYMBOL_GPL(pm_runtime_enable); + +/** + * pm_runtime_forbid - Block run-time PM of a device. + * @dev: Device to handle. + * + * Increase the device's usage count and clear its power.runtime_auto flag, + * so that it cannot be suspended at run time until pm_runtime_allow() is called + * for it. + */ +void pm_runtime_forbid(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + if (!dev->power.runtime_auto) + goto out; + + dev->power.runtime_auto = false; + atomic_inc(&dev->power.usage_count); + rpm_resume(dev, 0); + + out: + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(pm_runtime_forbid); + +/** + * pm_runtime_allow - Unblock run-time PM of a device. + * @dev: Device to handle. + * + * Decrease the device's usage count and set its power.runtime_auto flag. + */ +void pm_runtime_allow(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + if (dev->power.runtime_auto) + goto out; + + dev->power.runtime_auto = true; + if (atomic_dec_and_test(&dev->power.usage_count)) + rpm_idle(dev, RPM_AUTO); + + out: + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(pm_runtime_allow); + +/** + * pm_runtime_no_callbacks - Ignore run-time PM callbacks for a device. + * @dev: Device to handle. + * + * Set the power.no_callbacks flag, which tells the PM core that this + * device is power-managed through its parent and has no run-time PM + * callbacks of its own. The run-time sysfs attributes will be removed. + */ +void pm_runtime_no_callbacks(struct device *dev) +{ + spin_lock_irq(&dev->power.lock); + dev->power.no_callbacks = 1; + spin_unlock_irq(&dev->power.lock); + if (device_is_registered(dev)) + rpm_sysfs_remove(dev); +} +EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks); + +/** + * pm_runtime_irq_safe - Leave interrupts disabled during callbacks. + * @dev: Device to handle + * + * Set the power.irq_safe flag, which tells the PM core that the + * ->runtime_suspend() and ->runtime_resume() callbacks for this device should + * always be invoked with the spinlock held and interrupts disabled. It also + * causes the parent's usage counter to be permanently incremented, preventing + * the parent from runtime suspending -- otherwise an irq-safe child might have + * to wait for a non-irq-safe parent. + */ +void pm_runtime_irq_safe(struct device *dev) +{ + if (dev->parent) + pm_runtime_get_sync(dev->parent); + spin_lock_irq(&dev->power.lock); + dev->power.irq_safe = 1; + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(pm_runtime_irq_safe); + +/** + * update_autosuspend - Handle a change to a device's autosuspend settings. + * @dev: Device to handle. + * @old_delay: The former autosuspend_delay value. + * @old_use: The former use_autosuspend value. + * + * Prevent runtime suspend if the new delay is negative and use_autosuspend is + * set; otherwise allow it. Send an idle notification if suspends are allowed. + * + * This function must be called under dev->power.lock with interrupts disabled. + */ +static void update_autosuspend(struct device *dev, int old_delay, int old_use) +{ + int delay = dev->power.autosuspend_delay; + + /* Should runtime suspend be prevented now? */ + if (dev->power.use_autosuspend && delay < 0) { + + /* If it used to be allowed then prevent it. */ + if (!old_use || old_delay >= 0) { + atomic_inc(&dev->power.usage_count); + rpm_resume(dev, 0); + } + } + + /* Runtime suspend should be allowed now. */ + else { + + /* If it used to be prevented then allow it. */ + if (old_use && old_delay < 0) + atomic_dec(&dev->power.usage_count); + + /* Maybe we can autosuspend now. */ + rpm_idle(dev, RPM_AUTO); + } +} + +/** + * pm_runtime_set_autosuspend_delay - Set a device's autosuspend_delay value. + * @dev: Device to handle. + * @delay: Value of the new delay in milliseconds. + * + * Set the device's power.autosuspend_delay value. If it changes to negative + * and the power.use_autosuspend flag is set, prevent run-time suspends. If it + * changes the other way, allow run-time suspends. + */ +void pm_runtime_set_autosuspend_delay(struct device *dev, int delay) +{ + int old_delay, old_use; + + spin_lock_irq(&dev->power.lock); + old_delay = dev->power.autosuspend_delay; + old_use = dev->power.use_autosuspend; + dev->power.autosuspend_delay = delay; + update_autosuspend(dev, old_delay, old_use); + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(pm_runtime_set_autosuspend_delay); + +/** + * __pm_runtime_use_autosuspend - Set a device's use_autosuspend flag. + * @dev: Device to handle. + * @use: New value for use_autosuspend. + * + * Set the device's power.use_autosuspend flag, and allow or prevent run-time + * suspends as needed. + */ +void __pm_runtime_use_autosuspend(struct device *dev, bool use) +{ + int old_delay, old_use; + + might_sleep(); + + spin_lock_irq(&dev->power.lock); + old_delay = dev->power.autosuspend_delay; + old_use = dev->power.use_autosuspend; + dev->power.use_autosuspend = use; + update_autosuspend(dev, old_delay, old_use); + spin_unlock_irq(&dev->power.lock); +} +EXPORT_SYMBOL_GPL(__pm_runtime_use_autosuspend); + +/** + * pm_runtime_init - Initialize run-time PM fields in given device object. + * @dev: Device object to initialize. + */ +void pm_runtime_init(struct device *dev) +{ + dev->power.runtime_status = RPM_SUSPENDED; + dev->power.idle_notification = false; + + dev->power.disable_depth = 1; + atomic_set(&dev->power.usage_count, 0); + + dev->power.runtime_error = 0; + + atomic_set(&dev->power.child_count, 0); + pm_suspend_ignore_children(dev, false); + dev->power.runtime_auto = true; + + dev->power.request_pending = false; + dev->power.request = RPM_REQ_NONE; + dev->power.deferred_resume = false; + dev->power.accounting_timestamp = jiffies; + INIT_WORK(&dev->power.work, pm_runtime_work); + + dev->power.timer_expires = 0; + setup_timer(&dev->power.suspend_timer, pm_suspend_timer_fn, + (unsigned long)dev); + + init_waitqueue_head(&dev->power.wait_queue); +} + +/** + * pm_runtime_remove - Prepare for removing a device from device hierarchy. + * @dev: Device object being removed from device hierarchy. + */ +void pm_runtime_remove(struct device *dev) +{ + __pm_runtime_disable(dev, false); + + /* Change the status back to 'suspended' to match the initial status. */ + if (dev->power.runtime_status == RPM_ACTIVE) + pm_runtime_set_suspended(dev); + if (dev->power.irq_safe && dev->parent) + pm_runtime_put_sync(dev->parent); +} diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c new file mode 100644 index 00000000..a9f5b897 --- /dev/null +++ b/drivers/base/power/sysfs.c @@ -0,0 +1,538 @@ +/* + * drivers/base/power/sysfs.c - sysfs entries for device PM + */ + +#include <linux/device.h> +#include <linux/string.h> +#include <linux/pm_runtime.h> +#include <asm/atomic.h> +#include <linux/jiffies.h> +#include "power.h" + +/* + * control - Report/change current runtime PM setting of the device + * + * Runtime power management of a device can be blocked with the help of + * this attribute. All devices have one of the following two values for + * the power/control file: + * + * + "auto\n" to allow the device to be power managed at run time; + * + "on\n" to prevent the device from being power managed at run time; + * + * The default for all devices is "auto", which means that devices may be + * subject to automatic power management, depending on their drivers. + * Changing this attribute to "on" prevents the driver from power managing + * the device at run time. Doing that while the device is suspended causes + * it to be woken up. + * + * wakeup - Report/change current wakeup option for device + * + * Some devices support "wakeup" events, which are hardware signals + * used to activate devices from suspended or low power states. Such + * devices have one of three values for the sysfs power/wakeup file: + * + * + "enabled\n" to issue the events; + * + "disabled\n" not to do so; or + * + "\n" for temporary or permanent inability to issue wakeup. + * + * (For example, unconfigured USB devices can't issue wakeups.) + * + * Familiar examples of devices that can issue wakeup events include + * keyboards and mice (both PS2 and USB styles), power buttons, modems, + * "Wake-On-LAN" Ethernet links, GPIO lines, and more. Some events + * will wake the entire system from a suspend state; others may just + * wake up the device (if the system as a whole is already active). + * Some wakeup events use normal IRQ lines; other use special out + * of band signaling. + * + * It is the responsibility of device drivers to enable (or disable) + * wakeup signaling as part of changing device power states, respecting + * the policy choices provided through the driver model. + * + * Devices may not be able to generate wakeup events from all power + * states. Also, the events may be ignored in some configurations; + * for example, they might need help from other devices that aren't + * active, or which may have wakeup disabled. Some drivers rely on + * wakeup events internally (unless they are disabled), keeping + * their hardware in low power modes whenever they're unused. This + * saves runtime power, without requiring system-wide sleep states. + * + * async - Report/change current async suspend setting for the device + * + * Asynchronous suspend and resume of the device during system-wide power + * state transitions can be enabled by writing "enabled" to this file. + * Analogously, if "disabled" is written to this file, the device will be + * suspended and resumed synchronously. + * + * All devices have one of the following two values for power/async: + * + * + "enabled\n" to permit the asynchronous suspend/resume of the device; + * + "disabled\n" to forbid it; + * + * NOTE: It generally is unsafe to permit the asynchronous suspend/resume + * of a device unless it is certain that all of the PM dependencies of the + * device are known to the PM core. However, for some devices this + * attribute is set to "enabled" by bus type code or device drivers and in + * that cases it should be safe to leave the default value. + * + * autosuspend_delay_ms - Report/change a device's autosuspend_delay value + * + * Some drivers don't want to carry out a runtime suspend as soon as a + * device becomes idle; they want it always to remain idle for some period + * of time before suspending it. This period is the autosuspend_delay + * value (expressed in milliseconds) and it can be controlled by the user. + * If the value is negative then the device will never be runtime + * suspended. + * + * NOTE: The autosuspend_delay_ms attribute and the autosuspend_delay + * value are used only if the driver calls pm_runtime_use_autosuspend(). + * + * wakeup_count - Report the number of wakeup events related to the device + */ + +static const char enabled[] = "enabled"; +static const char disabled[] = "disabled"; + +const char power_group_name[] = "power"; +EXPORT_SYMBOL_GPL(power_group_name); + +#ifdef CONFIG_PM_RUNTIME +static const char ctrl_auto[] = "auto"; +static const char ctrl_on[] = "on"; + +static ssize_t control_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%s\n", + dev->power.runtime_auto ? ctrl_auto : ctrl_on); +} + +static ssize_t control_store(struct device * dev, struct device_attribute *attr, + const char * buf, size_t n) +{ + char *cp; + int len = n; + + cp = memchr(buf, '\n', n); + if (cp) + len = cp - buf; + if (len == sizeof ctrl_auto - 1 && strncmp(buf, ctrl_auto, len) == 0) + pm_runtime_allow(dev); + else if (len == sizeof ctrl_on - 1 && strncmp(buf, ctrl_on, len) == 0) + pm_runtime_forbid(dev); + else + return -EINVAL; + return n; +} + +static DEVICE_ATTR(control, 0644, control_show, control_store); + +static ssize_t rtpm_active_time_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int ret; + spin_lock_irq(&dev->power.lock); + update_pm_runtime_accounting(dev); + ret = sprintf(buf, "%i\n", jiffies_to_msecs(dev->power.active_jiffies)); + spin_unlock_irq(&dev->power.lock); + return ret; +} + +static DEVICE_ATTR(runtime_active_time, 0444, rtpm_active_time_show, NULL); + +static ssize_t rtpm_suspended_time_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int ret; + spin_lock_irq(&dev->power.lock); + update_pm_runtime_accounting(dev); + ret = sprintf(buf, "%i\n", + jiffies_to_msecs(dev->power.suspended_jiffies)); + spin_unlock_irq(&dev->power.lock); + return ret; +} + +static DEVICE_ATTR(runtime_suspended_time, 0444, rtpm_suspended_time_show, NULL); + +static ssize_t rtpm_status_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const char *p; + + if (dev->power.runtime_error) { + p = "error\n"; + } else if (dev->power.disable_depth) { + p = "unsupported\n"; + } else { + switch (dev->power.runtime_status) { + case RPM_SUSPENDED: + p = "suspended\n"; + break; + case RPM_SUSPENDING: + p = "suspending\n"; + break; + case RPM_RESUMING: + p = "resuming\n"; + break; + case RPM_ACTIVE: + p = "active\n"; + break; + default: + return -EIO; + } + } + return sprintf(buf, p); +} + +static DEVICE_ATTR(runtime_status, 0444, rtpm_status_show, NULL); + +static ssize_t autosuspend_delay_ms_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + if (!dev->power.use_autosuspend) + return -EIO; + return sprintf(buf, "%d\n", dev->power.autosuspend_delay); +} + +static ssize_t autosuspend_delay_ms_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t n) +{ + long delay; + + if (!dev->power.use_autosuspend) + return -EIO; + + if (strict_strtol(buf, 10, &delay) != 0 || delay != (int) delay) + return -EINVAL; + + pm_runtime_set_autosuspend_delay(dev, delay); + return n; +} + +static DEVICE_ATTR(autosuspend_delay_ms, 0644, autosuspend_delay_ms_show, + autosuspend_delay_ms_store); + +#endif /* CONFIG_PM_RUNTIME */ + +#ifdef CONFIG_PM_SLEEP +static ssize_t +wake_show(struct device * dev, struct device_attribute *attr, char * buf) +{ + return sprintf(buf, "%s\n", device_can_wakeup(dev) + ? (device_may_wakeup(dev) ? enabled : disabled) + : ""); +} + +static ssize_t +wake_store(struct device * dev, struct device_attribute *attr, + const char * buf, size_t n) +{ + char *cp; + int len = n; + + if (!device_can_wakeup(dev)) + return -EINVAL; + + cp = memchr(buf, '\n', n); + if (cp) + len = cp - buf; + if (len == sizeof enabled - 1 + && strncmp(buf, enabled, sizeof enabled - 1) == 0) + device_set_wakeup_enable(dev, 1); + else if (len == sizeof disabled - 1 + && strncmp(buf, disabled, sizeof disabled - 1) == 0) + device_set_wakeup_enable(dev, 0); + else + return -EINVAL; + return n; +} + +static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store); + +static ssize_t wakeup_count_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + unsigned long count = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + count = dev->power.wakeup->event_count; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR(wakeup_count, 0444, wakeup_count_show, NULL); + +static ssize_t wakeup_active_count_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + unsigned long count = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + count = dev->power.wakeup->active_count; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR(wakeup_active_count, 0444, wakeup_active_count_show, NULL); + +static ssize_t wakeup_hit_count_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + unsigned long count = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + count = dev->power.wakeup->hit_count; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR(wakeup_hit_count, 0444, wakeup_hit_count_show, NULL); + +static ssize_t wakeup_active_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + unsigned int active = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + active = dev->power.wakeup->active; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%u\n", active) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR(wakeup_active, 0444, wakeup_active_show, NULL); + +static ssize_t wakeup_total_time_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + s64 msec = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + msec = ktime_to_ms(dev->power.wakeup->total_time); + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR(wakeup_total_time_ms, 0444, wakeup_total_time_show, NULL); + +static ssize_t wakeup_max_time_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + s64 msec = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + msec = ktime_to_ms(dev->power.wakeup->max_time); + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR(wakeup_max_time_ms, 0444, wakeup_max_time_show, NULL); + +static ssize_t wakeup_last_time_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + s64 msec = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + msec = ktime_to_ms(dev->power.wakeup->last_time); + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR(wakeup_last_time_ms, 0444, wakeup_last_time_show, NULL); +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_PM_ADVANCED_DEBUG +#ifdef CONFIG_PM_RUNTIME + +static ssize_t rtpm_usagecount_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count)); +} + +static ssize_t rtpm_children_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", dev->power.ignore_children ? + 0 : atomic_read(&dev->power.child_count)); +} + +static ssize_t rtpm_enabled_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + if ((dev->power.disable_depth) && (dev->power.runtime_auto == false)) + return sprintf(buf, "disabled & forbidden\n"); + else if (dev->power.disable_depth) + return sprintf(buf, "disabled\n"); + else if (dev->power.runtime_auto == false) + return sprintf(buf, "forbidden\n"); + return sprintf(buf, "enabled\n"); +} + +static DEVICE_ATTR(runtime_usage, 0444, rtpm_usagecount_show, NULL); +static DEVICE_ATTR(runtime_active_kids, 0444, rtpm_children_show, NULL); +static DEVICE_ATTR(runtime_enabled, 0444, rtpm_enabled_show, NULL); + +#endif + +static ssize_t async_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%s\n", + device_async_suspend_enabled(dev) ? enabled : disabled); +} + +static ssize_t async_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t n) +{ + char *cp; + int len = n; + + cp = memchr(buf, '\n', n); + if (cp) + len = cp - buf; + if (len == sizeof enabled - 1 && strncmp(buf, enabled, len) == 0) + device_enable_async_suspend(dev); + else if (len == sizeof disabled - 1 && strncmp(buf, disabled, len) == 0) + device_disable_async_suspend(dev); + else + return -EINVAL; + return n; +} + +static DEVICE_ATTR(async, 0644, async_show, async_store); +#endif /* CONFIG_PM_ADVANCED_DEBUG */ + +static struct attribute *power_attrs[] = { +#ifdef CONFIG_PM_ADVANCED_DEBUG +#ifdef CONFIG_PM_SLEEP + &dev_attr_async.attr, +#endif +#ifdef CONFIG_PM_RUNTIME + &dev_attr_runtime_status.attr, + &dev_attr_runtime_usage.attr, + &dev_attr_runtime_active_kids.attr, + &dev_attr_runtime_enabled.attr, +#endif +#endif /* CONFIG_PM_ADVANCED_DEBUG */ + NULL, +}; +static struct attribute_group pm_attr_group = { + .name = power_group_name, + .attrs = power_attrs, +}; + +static struct attribute *wakeup_attrs[] = { +#ifdef CONFIG_PM_SLEEP + &dev_attr_wakeup.attr, + &dev_attr_wakeup_count.attr, + &dev_attr_wakeup_active_count.attr, + &dev_attr_wakeup_hit_count.attr, + &dev_attr_wakeup_active.attr, + &dev_attr_wakeup_total_time_ms.attr, + &dev_attr_wakeup_max_time_ms.attr, + &dev_attr_wakeup_last_time_ms.attr, +#endif + NULL, +}; +static struct attribute_group pm_wakeup_attr_group = { + .name = power_group_name, + .attrs = wakeup_attrs, +}; + +static struct attribute *runtime_attrs[] = { +#ifdef CONFIG_PM_RUNTIME +#ifndef CONFIG_PM_ADVANCED_DEBUG + &dev_attr_runtime_status.attr, +#endif + &dev_attr_control.attr, + &dev_attr_runtime_suspended_time.attr, + &dev_attr_runtime_active_time.attr, + &dev_attr_autosuspend_delay_ms.attr, +#endif /* CONFIG_PM_RUNTIME */ + NULL, +}; +static struct attribute_group pm_runtime_attr_group = { + .name = power_group_name, + .attrs = runtime_attrs, +}; + +int dpm_sysfs_add(struct device *dev) +{ + int rc; + + rc = sysfs_create_group(&dev->kobj, &pm_attr_group); + if (rc) + return rc; + + if (pm_runtime_callbacks_present(dev)) { + rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group); + if (rc) + goto err_out; + } + + if (device_can_wakeup(dev)) { + rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group); + if (rc) { + if (pm_runtime_callbacks_present(dev)) + sysfs_unmerge_group(&dev->kobj, + &pm_runtime_attr_group); + goto err_out; + } + } + return 0; + + err_out: + sysfs_remove_group(&dev->kobj, &pm_attr_group); + return rc; +} + +int wakeup_sysfs_add(struct device *dev) +{ + return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group); +} + +void wakeup_sysfs_remove(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group); +} + +void rpm_sysfs_remove(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group); +} + +void dpm_sysfs_remove(struct device *dev) +{ + rpm_sysfs_remove(dev); + sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group); + sysfs_remove_group(&dev->kobj, &pm_attr_group); +} diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c new file mode 100644 index 00000000..c80e138b --- /dev/null +++ b/drivers/base/power/trace.c @@ -0,0 +1,265 @@ +/* + * drivers/base/power/trace.c + * + * Copyright (C) 2006 Linus Torvalds + * + * Trace facility for suspend/resume problems, when none of the + * devices may be working. + */ + +#include <linux/resume-trace.h> +#include <linux/rtc.h> + +#include <asm/rtc.h> + +#include "power.h" + +/* + * Horrid, horrid, horrid. + * + * It turns out that the _only_ piece of hardware that actually + * keeps its value across a hard boot (and, more importantly, the + * POST init sequence) is literally the realtime clock. + * + * Never mind that an RTC chip has 114 bytes (and often a whole + * other bank of an additional 128 bytes) of nice SRAM that is + * _designed_ to keep data - the POST will clear it. So we literally + * can just use the few bytes of actual time data, which means that + * we're really limited. + * + * It means, for example, that we can't use the seconds at all + * (since the time between the hang and the boot might be more + * than a minute), and we'd better not depend on the low bits of + * the minutes either. + * + * There are the wday fields etc, but I wouldn't guarantee those + * are dependable either. And if the date isn't valid, either the + * hw or POST will do strange things. + * + * So we're left with: + * - year: 0-99 + * - month: 0-11 + * - day-of-month: 1-28 + * - hour: 0-23 + * - min: (0-30)*2 + * + * Giving us a total range of 0-16128000 (0xf61800), ie less + * than 24 bits of actual data we can save across reboots. + * + * And if your box can't boot in less than three minutes, + * you're screwed. + * + * Now, almost 24 bits of data is pitifully small, so we need + * to be pretty dense if we want to use it for anything nice. + * What we do is that instead of saving off nice readable info, + * we save off _hashes_ of information that we can hopefully + * regenerate after the reboot. + * + * In particular, this means that we might be unlucky, and hit + * a case where we have a hash collision, and we end up not + * being able to tell for certain exactly which case happened. + * But that's hopefully unlikely. + * + * What we do is to take the bits we can fit, and split them + * into three parts (16*997*1009 = 16095568), and use the values + * for: + * - 0-15: user-settable + * - 0-996: file + line number + * - 0-1008: device + */ +#define USERHASH (16) +#define FILEHASH (997) +#define DEVHASH (1009) + +#define DEVSEED (7919) + +static unsigned int dev_hash_value; + +static int set_magic_time(unsigned int user, unsigned int file, unsigned int device) +{ + unsigned int n = user + USERHASH*(file + FILEHASH*device); + + // June 7th, 2006 + static struct rtc_time time = { + .tm_sec = 0, + .tm_min = 0, + .tm_hour = 0, + .tm_mday = 7, + .tm_mon = 5, // June - counting from zero + .tm_year = 106, + .tm_wday = 3, + .tm_yday = 160, + .tm_isdst = 1 + }; + + time.tm_year = (n % 100); + n /= 100; + time.tm_mon = (n % 12); + n /= 12; + time.tm_mday = (n % 28) + 1; + n /= 28; + time.tm_hour = (n % 24); + n /= 24; + time.tm_min = (n % 20) * 3; + n /= 20; + set_rtc_time(&time); + return n ? -1 : 0; +} + +static unsigned int read_magic_time(void) +{ + struct rtc_time time; + unsigned int val; + + get_rtc_time(&time); + pr_info("Time: %2d:%02d:%02d Date: %02d/%02d/%02d\n", + time.tm_hour, time.tm_min, time.tm_sec, + time.tm_mon + 1, time.tm_mday, time.tm_year % 100); + val = time.tm_year; /* 100 years */ + if (val > 100) + val -= 100; + val += time.tm_mon * 100; /* 12 months */ + val += (time.tm_mday-1) * 100 * 12; /* 28 month-days */ + val += time.tm_hour * 100 * 12 * 28; /* 24 hours */ + val += (time.tm_min / 3) * 100 * 12 * 28 * 24; /* 20 3-minute intervals */ + return val; +} + +/* + * This is just the sdbm hash function with a user-supplied + * seed and final size parameter. + */ +static unsigned int hash_string(unsigned int seed, const char *data, unsigned int mod) +{ + unsigned char c; + while ((c = *data++) != 0) { + seed = (seed << 16) + (seed << 6) - seed + c; + } + return seed % mod; +} + +void set_trace_device(struct device *dev) +{ + dev_hash_value = hash_string(DEVSEED, dev_name(dev), DEVHASH); +} +EXPORT_SYMBOL(set_trace_device); + +/* + * We could just take the "tracedata" index into the .tracedata + * section instead. Generating a hash of the data gives us a + * chance to work across kernel versions, and perhaps more + * importantly it also gives us valid/invalid check (ie we will + * likely not give totally bogus reports - if the hash matches, + * it's not any guarantee, but it's a high _likelihood_ that + * the match is valid). + */ +void generate_resume_trace(const void *tracedata, unsigned int user) +{ + unsigned short lineno = *(unsigned short *)tracedata; + const char *file = *(const char **)(tracedata + 2); + unsigned int user_hash_value, file_hash_value; + + user_hash_value = user % USERHASH; + file_hash_value = hash_string(lineno, file, FILEHASH); + set_magic_time(user_hash_value, file_hash_value, dev_hash_value); +} +EXPORT_SYMBOL(generate_resume_trace); + +extern char __tracedata_start, __tracedata_end; +static int show_file_hash(unsigned int value) +{ + int match; + char *tracedata; + + match = 0; + for (tracedata = &__tracedata_start ; tracedata < &__tracedata_end ; + tracedata += 2 + sizeof(unsigned long)) { + unsigned short lineno = *(unsigned short *)tracedata; + const char *file = *(const char **)(tracedata + 2); + unsigned int hash = hash_string(lineno, file, FILEHASH); + if (hash != value) + continue; + pr_info(" hash matches %s:%u\n", file, lineno); + match++; + } + return match; +} + +static int show_dev_hash(unsigned int value) +{ + int match = 0; + struct list_head *entry; + + device_pm_lock(); + entry = dpm_list.prev; + while (entry != &dpm_list) { + struct device * dev = to_device(entry); + unsigned int hash = hash_string(DEVSEED, dev_name(dev), DEVHASH); + if (hash == value) { + dev_info(dev, "hash matches\n"); + match++; + } + entry = entry->prev; + } + device_pm_unlock(); + return match; +} + +static unsigned int hash_value_early_read; + +int show_trace_dev_match(char *buf, size_t size) +{ + unsigned int value = hash_value_early_read / (USERHASH * FILEHASH); + int ret = 0; + struct list_head *entry; + + /* + * It's possible that multiple devices will match the hash and we can't + * tell which is the culprit, so it's best to output them all. + */ + device_pm_lock(); + entry = dpm_list.prev; + while (size && entry != &dpm_list) { + struct device *dev = to_device(entry); + unsigned int hash = hash_string(DEVSEED, dev_name(dev), + DEVHASH); + if (hash == value) { + int len = snprintf(buf, size, "%s\n", + dev_driver_string(dev)); + if (len > size) + len = size; + buf += len; + ret += len; + size -= len; + } + entry = entry->prev; + } + device_pm_unlock(); + return ret; +} + +static int early_resume_init(void) +{ + hash_value_early_read = read_magic_time(); + return 0; +} + +static int late_resume_init(void) +{ + unsigned int val = hash_value_early_read; + unsigned int user, file, dev; + + user = val % USERHASH; + val = val / USERHASH; + file = val % FILEHASH; + val = val / FILEHASH; + dev = val /* % DEVHASH */; + + pr_info(" Magic number: %d:%d:%d\n", user, file, dev); + show_file_hash(file); + show_dev_hash(dev); + return 0; +} + +core_initcall(early_resume_init); +late_initcall(late_resume_init); diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c new file mode 100644 index 00000000..84f7c7d5 --- /dev/null +++ b/drivers/base/power/wakeup.c @@ -0,0 +1,746 @@ +/* + * drivers/base/power/wakeup.c - System wakeup events framework + * + * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + * + * This file is released under the GPLv2. + */ + +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/capability.h> +#include <linux/suspend.h> +#include <linux/seq_file.h> +#include <linux/debugfs.h> + +#include "power.h" + +#define TIMEOUT 100 + +/* + * If set, the suspend/hibernate code will abort transitions to a sleep state + * if wakeup events are registered during or immediately before the transition. + */ +bool events_check_enabled; + +/* + * Combined counters of registered wakeup events and wakeup events in progress. + * They need to be modified together atomically, so it's better to use one + * atomic variable to hold them both. + */ +static atomic_t combined_event_count = ATOMIC_INIT(0); + +#define IN_PROGRESS_BITS (sizeof(int) * 4) +#define MAX_IN_PROGRESS ((1 << IN_PROGRESS_BITS) - 1) + +static void split_counters(unsigned int *cnt, unsigned int *inpr) +{ + unsigned int comb = atomic_read(&combined_event_count); + + *cnt = (comb >> IN_PROGRESS_BITS); + *inpr = comb & MAX_IN_PROGRESS; +} + +/* A preserved old value of the events counter. */ +static unsigned int saved_count; + +static DEFINE_SPINLOCK(events_lock); + +static void pm_wakeup_timer_fn(unsigned long data); + +static LIST_HEAD(wakeup_sources); + +/** + * wakeup_source_create - Create a struct wakeup_source object. + * @name: Name of the new wakeup source. + */ +struct wakeup_source *wakeup_source_create(const char *name) +{ + struct wakeup_source *ws; + + ws = kzalloc(sizeof(*ws), GFP_KERNEL); + if (!ws) + return NULL; + + spin_lock_init(&ws->lock); + if (name) + ws->name = kstrdup(name, GFP_KERNEL); + + return ws; +} +EXPORT_SYMBOL_GPL(wakeup_source_create); + +/** + * wakeup_source_destroy - Destroy a struct wakeup_source object. + * @ws: Wakeup source to destroy. + */ +void wakeup_source_destroy(struct wakeup_source *ws) +{ + if (!ws) + return; + + spin_lock_irq(&ws->lock); + while (ws->active) { + spin_unlock_irq(&ws->lock); + + schedule_timeout_interruptible(msecs_to_jiffies(TIMEOUT)); + + spin_lock_irq(&ws->lock); + } + spin_unlock_irq(&ws->lock); + + kfree(ws->name); + kfree(ws); +} +EXPORT_SYMBOL_GPL(wakeup_source_destroy); + +/** + * wakeup_source_add - Add given object to the list of wakeup sources. + * @ws: Wakeup source object to add to the list. + */ +void wakeup_source_add(struct wakeup_source *ws) +{ + if (WARN_ON(!ws)) + return; + + setup_timer(&ws->timer, pm_wakeup_timer_fn, (unsigned long)ws); + ws->active = false; + + spin_lock_irq(&events_lock); + list_add_rcu(&ws->entry, &wakeup_sources); + spin_unlock_irq(&events_lock); +} +EXPORT_SYMBOL_GPL(wakeup_source_add); + +/** + * wakeup_source_remove - Remove given object from the wakeup sources list. + * @ws: Wakeup source object to remove from the list. + */ +void wakeup_source_remove(struct wakeup_source *ws) +{ + if (WARN_ON(!ws)) + return; + + spin_lock_irq(&events_lock); + list_del_rcu(&ws->entry); + spin_unlock_irq(&events_lock); + synchronize_rcu(); +} +EXPORT_SYMBOL_GPL(wakeup_source_remove); + +/** + * wakeup_source_register - Create wakeup source and add it to the list. + * @name: Name of the wakeup source to register. + */ +struct wakeup_source *wakeup_source_register(const char *name) +{ + struct wakeup_source *ws; + + ws = wakeup_source_create(name); + if (ws) + wakeup_source_add(ws); + + return ws; +} +EXPORT_SYMBOL_GPL(wakeup_source_register); + +/** + * wakeup_source_unregister - Remove wakeup source from the list and remove it. + * @ws: Wakeup source object to unregister. + */ +void wakeup_source_unregister(struct wakeup_source *ws) +{ + wakeup_source_remove(ws); + wakeup_source_destroy(ws); +} +EXPORT_SYMBOL_GPL(wakeup_source_unregister); + +/** + * device_wakeup_attach - Attach a wakeup source object to a device object. + * @dev: Device to handle. + * @ws: Wakeup source object to attach to @dev. + * + * This causes @dev to be treated as a wakeup device. + */ +static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws) +{ + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + spin_unlock_irq(&dev->power.lock); + return -EEXIST; + } + dev->power.wakeup = ws; + spin_unlock_irq(&dev->power.lock); + return 0; +} + +/** + * device_wakeup_enable - Enable given device to be a wakeup source. + * @dev: Device to handle. + * + * Create a wakeup source object, register it and attach it to @dev. + */ +int device_wakeup_enable(struct device *dev) +{ + struct wakeup_source *ws; + int ret; + + if (!dev || !dev->power.can_wakeup) + return -EINVAL; + + ws = wakeup_source_register(dev_name(dev)); + if (!ws) + return -ENOMEM; + + ret = device_wakeup_attach(dev, ws); + if (ret) + wakeup_source_unregister(ws); + + return ret; +} +EXPORT_SYMBOL_GPL(device_wakeup_enable); + +/** + * device_wakeup_detach - Detach a device's wakeup source object from it. + * @dev: Device to detach the wakeup source object from. + * + * After it returns, @dev will not be treated as a wakeup device any more. + */ +static struct wakeup_source *device_wakeup_detach(struct device *dev) +{ + struct wakeup_source *ws; + + spin_lock_irq(&dev->power.lock); + ws = dev->power.wakeup; + dev->power.wakeup = NULL; + spin_unlock_irq(&dev->power.lock); + return ws; +} + +/** + * device_wakeup_disable - Do not regard a device as a wakeup source any more. + * @dev: Device to handle. + * + * Detach the @dev's wakeup source object from it, unregister this wakeup source + * object and destroy it. + */ +int device_wakeup_disable(struct device *dev) +{ + struct wakeup_source *ws; + + if (!dev || !dev->power.can_wakeup) + return -EINVAL; + + ws = device_wakeup_detach(dev); + if (ws) + wakeup_source_unregister(ws); + + return 0; +} +EXPORT_SYMBOL_GPL(device_wakeup_disable); + +/** + * device_set_wakeup_capable - Set/reset device wakeup capability flag. + * @dev: Device to handle. + * @capable: Whether or not @dev is capable of waking up the system from sleep. + * + * If @capable is set, set the @dev's power.can_wakeup flag and add its + * wakeup-related attributes to sysfs. Otherwise, unset the @dev's + * power.can_wakeup flag and remove its wakeup-related attributes from sysfs. + * + * This function may sleep and it can't be called from any context where + * sleeping is not allowed. + */ +void device_set_wakeup_capable(struct device *dev, bool capable) +{ + if (!!dev->power.can_wakeup == !!capable) + return; + + if (device_is_registered(dev) && !list_empty(&dev->power.entry)) { + if (capable) { + if (wakeup_sysfs_add(dev)) + return; + } else { + wakeup_sysfs_remove(dev); + } + } + dev->power.can_wakeup = capable; +} +EXPORT_SYMBOL_GPL(device_set_wakeup_capable); + +/** + * device_init_wakeup - Device wakeup initialization. + * @dev: Device to handle. + * @enable: Whether or not to enable @dev as a wakeup device. + * + * By default, most devices should leave wakeup disabled. The exceptions are + * devices that everyone expects to be wakeup sources: keyboards, power buttons, + * possibly network interfaces, etc. + */ +int device_init_wakeup(struct device *dev, bool enable) +{ + int ret = 0; + + if (enable) { + device_set_wakeup_capable(dev, true); + ret = device_wakeup_enable(dev); + } else { + device_set_wakeup_capable(dev, false); + } + + return ret; +} +EXPORT_SYMBOL_GPL(device_init_wakeup); + +/** + * device_set_wakeup_enable - Enable or disable a device to wake up the system. + * @dev: Device to handle. + */ +int device_set_wakeup_enable(struct device *dev, bool enable) +{ + if (!dev || !dev->power.can_wakeup) + return -EINVAL; + + return enable ? device_wakeup_enable(dev) : device_wakeup_disable(dev); +} +EXPORT_SYMBOL_GPL(device_set_wakeup_enable); + +/* + * The functions below use the observation that each wakeup event starts a + * period in which the system should not be suspended. The moment this period + * will end depends on how the wakeup event is going to be processed after being + * detected and all of the possible cases can be divided into two distinct + * groups. + * + * First, a wakeup event may be detected by the same functional unit that will + * carry out the entire processing of it and possibly will pass it to user space + * for further processing. In that case the functional unit that has detected + * the event may later "close" the "no suspend" period associated with it + * directly as soon as it has been dealt with. The pair of pm_stay_awake() and + * pm_relax(), balanced with each other, is supposed to be used in such + * situations. + * + * Second, a wakeup event may be detected by one functional unit and processed + * by another one. In that case the unit that has detected it cannot really + * "close" the "no suspend" period associated with it, unless it knows in + * advance what's going to happen to the event during processing. This + * knowledge, however, may not be available to it, so it can simply specify time + * to wait before the system can be suspended and pass it as the second + * argument of pm_wakeup_event(). + * + * It is valid to call pm_relax() after pm_wakeup_event(), in which case the + * "no suspend" period will be ended either by the pm_relax(), or by the timer + * function executed when the timer expires, whichever comes first. + */ + +/** + * wakup_source_activate - Mark given wakeup source as active. + * @ws: Wakeup source to handle. + * + * Update the @ws' statistics and, if @ws has just been activated, notify the PM + * core of the event by incrementing the counter of of wakeup events being + * processed. + */ +static void wakeup_source_activate(struct wakeup_source *ws) +{ + ws->active = true; + ws->active_count++; + ws->timer_expires = jiffies; + ws->last_time = ktime_get(); + + /* Increment the counter of events in progress. */ + atomic_inc(&combined_event_count); +} + +/** + * __pm_stay_awake - Notify the PM core of a wakeup event. + * @ws: Wakeup source object associated with the source of the event. + * + * It is safe to call this function from interrupt context. + */ +void __pm_stay_awake(struct wakeup_source *ws) +{ + unsigned long flags; + + if (!ws) + return; + + spin_lock_irqsave(&ws->lock, flags); + ws->event_count++; + if (!ws->active) + wakeup_source_activate(ws); + spin_unlock_irqrestore(&ws->lock, flags); +} +EXPORT_SYMBOL_GPL(__pm_stay_awake); + +/** + * pm_stay_awake - Notify the PM core that a wakeup event is being processed. + * @dev: Device the wakeup event is related to. + * + * Notify the PM core of a wakeup event (signaled by @dev) by calling + * __pm_stay_awake for the @dev's wakeup source object. + * + * Call this function after detecting of a wakeup event if pm_relax() is going + * to be called directly after processing the event (and possibly passing it to + * user space for further processing). + */ +void pm_stay_awake(struct device *dev) +{ + unsigned long flags; + + if (!dev) + return; + + spin_lock_irqsave(&dev->power.lock, flags); + __pm_stay_awake(dev->power.wakeup); + spin_unlock_irqrestore(&dev->power.lock, flags); +} +EXPORT_SYMBOL_GPL(pm_stay_awake); + +/** + * wakup_source_deactivate - Mark given wakeup source as inactive. + * @ws: Wakeup source to handle. + * + * Update the @ws' statistics and notify the PM core that the wakeup source has + * become inactive by decrementing the counter of wakeup events being processed + * and incrementing the counter of registered wakeup events. + */ +static void wakeup_source_deactivate(struct wakeup_source *ws) +{ + ktime_t duration; + ktime_t now; + + ws->relax_count++; + /* + * __pm_relax() may be called directly or from a timer function. + * If it is called directly right after the timer function has been + * started, but before the timer function calls __pm_relax(), it is + * possible that __pm_stay_awake() will be called in the meantime and + * will set ws->active. Then, ws->active may be cleared immediately + * by the __pm_relax() called from the timer function, but in such a + * case ws->relax_count will be different from ws->active_count. + */ + if (ws->relax_count != ws->active_count) { + ws->relax_count--; + return; + } + + ws->active = false; + + now = ktime_get(); + duration = ktime_sub(now, ws->last_time); + ws->total_time = ktime_add(ws->total_time, duration); + if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time)) + ws->max_time = duration; + + del_timer(&ws->timer); + + /* + * Increment the counter of registered wakeup events and decrement the + * couter of wakeup events in progress simultaneously. + */ + atomic_add(MAX_IN_PROGRESS, &combined_event_count); +} + +/** + * __pm_relax - Notify the PM core that processing of a wakeup event has ended. + * @ws: Wakeup source object associated with the source of the event. + * + * Call this function for wakeup events whose processing started with calling + * __pm_stay_awake(). + * + * It is safe to call it from interrupt context. + */ +void __pm_relax(struct wakeup_source *ws) +{ + unsigned long flags; + + if (!ws) + return; + + spin_lock_irqsave(&ws->lock, flags); + if (ws->active) + wakeup_source_deactivate(ws); + spin_unlock_irqrestore(&ws->lock, flags); +} +EXPORT_SYMBOL_GPL(__pm_relax); + +/** + * pm_relax - Notify the PM core that processing of a wakeup event has ended. + * @dev: Device that signaled the event. + * + * Execute __pm_relax() for the @dev's wakeup source object. + */ +void pm_relax(struct device *dev) +{ + unsigned long flags; + + if (!dev) + return; + + spin_lock_irqsave(&dev->power.lock, flags); + __pm_relax(dev->power.wakeup); + spin_unlock_irqrestore(&dev->power.lock, flags); +} +EXPORT_SYMBOL_GPL(pm_relax); + +/** + * pm_wakeup_timer_fn - Delayed finalization of a wakeup event. + * @data: Address of the wakeup source object associated with the event source. + * + * Call __pm_relax() for the wakeup source whose address is stored in @data. + */ +static void pm_wakeup_timer_fn(unsigned long data) +{ + __pm_relax((struct wakeup_source *)data); +} + +/** + * __pm_wakeup_event - Notify the PM core of a wakeup event. + * @ws: Wakeup source object associated with the event source. + * @msec: Anticipated event processing time (in milliseconds). + * + * Notify the PM core of a wakeup event whose source is @ws that will take + * approximately @msec milliseconds to be processed by the kernel. If @ws is + * not active, activate it. If @msec is nonzero, set up the @ws' timer to + * execute pm_wakeup_timer_fn() in future. + * + * It is safe to call this function from interrupt context. + */ +void __pm_wakeup_event(struct wakeup_source *ws, unsigned int msec) +{ + unsigned long flags; + unsigned long expires; + + if (!ws) + return; + + spin_lock_irqsave(&ws->lock, flags); + + ws->event_count++; + if (!ws->active) + wakeup_source_activate(ws); + + if (!msec) { + wakeup_source_deactivate(ws); + goto unlock; + } + + expires = jiffies + msecs_to_jiffies(msec); + if (!expires) + expires = 1; + + if (time_after(expires, ws->timer_expires)) { + mod_timer(&ws->timer, expires); + ws->timer_expires = expires; + } + + unlock: + spin_unlock_irqrestore(&ws->lock, flags); +} +EXPORT_SYMBOL_GPL(__pm_wakeup_event); + + +/** + * pm_wakeup_event - Notify the PM core of a wakeup event. + * @dev: Device the wakeup event is related to. + * @msec: Anticipated event processing time (in milliseconds). + * + * Call __pm_wakeup_event() for the @dev's wakeup source object. + */ +void pm_wakeup_event(struct device *dev, unsigned int msec) +{ + unsigned long flags; + + if (!dev) + return; + + spin_lock_irqsave(&dev->power.lock, flags); + __pm_wakeup_event(dev->power.wakeup, msec); + spin_unlock_irqrestore(&dev->power.lock, flags); +} +EXPORT_SYMBOL_GPL(pm_wakeup_event); + +/** + * pm_wakeup_update_hit_counts - Update hit counts of all active wakeup sources. + */ +static void pm_wakeup_update_hit_counts(void) +{ + unsigned long flags; + struct wakeup_source *ws; + + rcu_read_lock(); + list_for_each_entry_rcu(ws, &wakeup_sources, entry) { + spin_lock_irqsave(&ws->lock, flags); + if (ws->active) + ws->hit_count++; + spin_unlock_irqrestore(&ws->lock, flags); + } + rcu_read_unlock(); +} + +/** + * pm_wakeup_pending - Check if power transition in progress should be aborted. + * + * Compare the current number of registered wakeup events with its preserved + * value from the past and return true if new wakeup events have been registered + * since the old value was stored. Also return true if the current number of + * wakeup events being processed is different from zero. + */ +bool pm_wakeup_pending(void) +{ + unsigned long flags; + bool ret = false; + + spin_lock_irqsave(&events_lock, flags); + if (events_check_enabled) { + unsigned int cnt, inpr; + + split_counters(&cnt, &inpr); + ret = (cnt != saved_count || inpr > 0); + events_check_enabled = !ret; + } + spin_unlock_irqrestore(&events_lock, flags); + if (ret) + pm_wakeup_update_hit_counts(); + return ret; +} + +/** + * pm_get_wakeup_count - Read the number of registered wakeup events. + * @count: Address to store the value at. + * + * Store the number of registered wakeup events at the address in @count. Block + * if the current number of wakeup events being processed is nonzero. + * + * Return 'false' if the wait for the number of wakeup events being processed to + * drop down to zero has been interrupted by a signal (and the current number + * of wakeup events being processed is still nonzero). Otherwise return 'true'. + */ +bool pm_get_wakeup_count(unsigned int *count) +{ + unsigned int cnt, inpr; + + for (;;) { + split_counters(&cnt, &inpr); + if (inpr == 0 || signal_pending(current)) + break; + pm_wakeup_update_hit_counts(); + schedule_timeout_interruptible(msecs_to_jiffies(TIMEOUT)); + } + + split_counters(&cnt, &inpr); + *count = cnt; + return !inpr; +} + +/** + * pm_save_wakeup_count - Save the current number of registered wakeup events. + * @count: Value to compare with the current number of registered wakeup events. + * + * If @count is equal to the current number of registered wakeup events and the + * current number of wakeup events being processed is zero, store @count as the + * old number of registered wakeup events for pm_check_wakeup_events(), enable + * wakeup events detection and return 'true'. Otherwise disable wakeup events + * detection and return 'false'. + */ +bool pm_save_wakeup_count(unsigned int count) +{ + unsigned int cnt, inpr; + + events_check_enabled = false; + spin_lock_irq(&events_lock); + split_counters(&cnt, &inpr); + if (cnt == count && inpr == 0) { + saved_count = count; + events_check_enabled = true; + } + spin_unlock_irq(&events_lock); + if (!events_check_enabled) + pm_wakeup_update_hit_counts(); + return events_check_enabled; +} + +static struct dentry *wakeup_sources_stats_dentry; + +/** + * print_wakeup_source_stats - Print wakeup source statistics information. + * @m: seq_file to print the statistics into. + * @ws: Wakeup source object to print the statistics for. + */ +static int print_wakeup_source_stats(struct seq_file *m, + struct wakeup_source *ws) +{ + unsigned long flags; + ktime_t total_time; + ktime_t max_time; + unsigned long active_count; + ktime_t active_time; + int ret; + + spin_lock_irqsave(&ws->lock, flags); + + total_time = ws->total_time; + max_time = ws->max_time; + active_count = ws->active_count; + if (ws->active) { + active_time = ktime_sub(ktime_get(), ws->last_time); + total_time = ktime_add(total_time, active_time); + if (active_time.tv64 > max_time.tv64) + max_time = active_time; + } else { + active_time = ktime_set(0, 0); + } + + ret = seq_printf(m, "%-12s\t%lu\t\t%lu\t\t%lu\t\t" + "%lld\t\t%lld\t\t%lld\t\t%lld\n", + ws->name, active_count, ws->event_count, ws->hit_count, + ktime_to_ms(active_time), ktime_to_ms(total_time), + ktime_to_ms(max_time), ktime_to_ms(ws->last_time)); + + spin_unlock_irqrestore(&ws->lock, flags); + + return ret; +} + +/** + * wakeup_sources_stats_show - Print wakeup sources statistics information. + * @m: seq_file to print the statistics into. + */ +static int wakeup_sources_stats_show(struct seq_file *m, void *unused) +{ + struct wakeup_source *ws; + + seq_puts(m, "name\t\tactive_count\tevent_count\thit_count\t" + "active_since\ttotal_time\tmax_time\tlast_change\n"); + + rcu_read_lock(); + list_for_each_entry_rcu(ws, &wakeup_sources, entry) + print_wakeup_source_stats(m, ws); + rcu_read_unlock(); + + return 0; +} + +static int wakeup_sources_stats_open(struct inode *inode, struct file *file) +{ + return single_open(file, wakeup_sources_stats_show, NULL); +} + +static const struct file_operations wakeup_sources_stats_fops = { + .owner = THIS_MODULE, + .open = wakeup_sources_stats_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static int __init wakeup_sources_debugfs_init(void) +{ + wakeup_sources_stats_dentry = debugfs_create_file("wakeup_sources", + S_IRUGO, NULL, NULL, &wakeup_sources_stats_fops); + return 0; +} + +postcore_initcall(wakeup_sources_debugfs_init); |