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author | Florian Fainelli <florian@openwrt.org> | 2008-12-17 14:06:03 +0000 |
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committer | Florian Fainelli <florian@openwrt.org> | 2008-12-17 14:06:03 +0000 |
commit | 7ab973e1af9cd0f8153daa892c88cfacfe3ebf4c (patch) | |
tree | 3531da38ed263505765e424ed6e31d45b5621a6c /target/linux/brcm63xx/files/drivers/watchdog/bcm63xx_wdt.c | |
parent | 0a74666c128cc3ba64c700a0e05b5f9d27bfbf0c (diff) | |
download | master-31e0f0ae-7ab973e1af9cd0f8153daa892c88cfacfe3ebf4c.tar.gz master-31e0f0ae-7ab973e1af9cd0f8153daa892c88cfacfe3ebf4c.tar.bz2 master-31e0f0ae-7ab973e1af9cd0f8153daa892c88cfacfe3ebf4c.zip |
Add bcm63xx_wdt but do not enable it yet
SVN-Revision: 13677
Diffstat (limited to 'target/linux/brcm63xx/files/drivers/watchdog/bcm63xx_wdt.c')
-rw-r--r-- | target/linux/brcm63xx/files/drivers/watchdog/bcm63xx_wdt.c | 315 |
1 files changed, 315 insertions, 0 deletions
diff --git a/target/linux/brcm63xx/files/drivers/watchdog/bcm63xx_wdt.c b/target/linux/brcm63xx/files/drivers/watchdog/bcm63xx_wdt.c new file mode 100644 index 0000000000..b40c52ad96 --- /dev/null +++ b/target/linux/brcm63xx/files/drivers/watchdog/bcm63xx_wdt.c @@ -0,0 +1,315 @@ +/* + * Broadcom BCM63xx SoC watchdog driver + * + * Copyright (C) 2007, Miguel Gaio <miguel.gaio@efixo.com> + * Copyright (C) 2008, Florian Fainelli <florian@openwrt.org> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/mm.h> +#include <linux/miscdevice.h> +#include <linux/watchdog.h> +#include <linux/reboot.h> +#include <linux/smp_lock.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/uaccess.h> +#include <linux/timer.h> + +#include <bcm63xx_cpu.h> +#include <bcm63xx_io.h> +#include <bcm63xx_regs.h> + +#define PFX KBUILD_MODNAME + +#define WDT_HZ 50000000 /* Fclk */ +#define WDT_INTERVAL (40) /* in seconds */ + +static struct { + void __iomem *regs; + struct completion stop; + int running; + struct timer_list timer; + int queue; + int default_ticks; + unsigned long inuse; +} bcm63xx_wdt_device; + +static int ticks = 100 * WDT_HZ; + +static int expect_close; +static int timeout; + +static int nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, int, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + + +static void bcm63xx_wdt_toggle(void) +{ + bcm_writel(WDT_START_1, bcm63xx_wdt_device.regs + WDT_CTL_REG); + bcm_writel(WDT_START_2, bcm63xx_wdt_device.regs + WDT_CTL_REG); +} + +static void bcm63xx_wdt_start(void) +{ + if (!bcm63xx_wdt_device.inuse) { + bcm63xx_wdt_toggle(); + mod_timer(&bcm63xx_wdt_device.timer, jiffies + WDT_INTERVAL); + } + + bcm63xx_wdt_device.running++; +} + +static void bcm63xx_wdt_stop(void) +{ + if (bcm63xx_wdt_device.running) { + bcm_writel(WDT_STOP_1, bcm63xx_wdt_device.regs + WDT_CTL_REG); + bcm_writel(WDT_STOP_2, bcm63xx_wdt_device.regs + WDT_CTL_REG); + + bcm63xx_wdt_device.running = 0; + } +} + +static void bcm63xx_wdt_set(int new_timeout) +{ + new_timeout *= WDT_HZ; + bcm_writel(new_timeout, bcm63xx_wdt_device.regs + WDT_DEFVAL_REG); +} + +static void bcm63xx_wdt_reset(void) +{ + ticks = bcm63xx_wdt_device.default_ticks; +} + +static void bcm63xx_wdt_update(unsigned long unused) +{ + if (bcm63xx_wdt_device.running) + ticks--; + + bcm63xx_wdt_toggle(); + + if (bcm63xx_wdt_device.queue && ticks) + mod_timer(&bcm63xx_wdt_device.timer, + jiffies + WDT_INTERVAL); + else + complete(&bcm63xx_wdt_device.stop); +} + +static int bcm63xx_wdt_open(struct inode *inode, struct file *file) +{ + if (test_and_set_bit(0, &bcm63xx_wdt_device.inuse)) + return -EBUSY; + + if (nowayout) + __module_get(THIS_MODULE); + + return nonseekable_open(inode, file); +} + +static int bcm63xx_wdt_release(struct inode *inode, struct file *file) +{ + if (expect_close && nowayout == 0) { + bcm63xx_wdt_stop(); + printk(KERN_INFO PFX ": disabling watchdog timer\n"); + module_put(THIS_MODULE); + } else + printk(KERN_CRIT PFX + ": device closed unexpectedly. WDT will not stop !\n"); + + clear_bit(0, &bcm63xx_wdt_device.inuse); + return 0; +} + +static ssize_t bcm63xx_wdt_write(struct file *file, const char *data, + size_t len, loff_t *ppos) +{ + if (len) { + if (!nowayout) { + size_t i; + + /* In case it was set long ago */ + expect_close = 0; + + for (i = 0; i != len; i++) { + char c; + if (get_user(c, data + i)) + return -EFAULT; + if (c == 'V') + expect_close = 1; + } + } + bcm63xx_wdt_update(0); + return len; + } + return 0; +} + +static long bcm63xx_wdt_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + void __user *argp = (void __user *)arg; + int new_timeout; + unsigned int value; + static struct watchdog_info ident = { + .options = WDIOF_SETTIMEOUT | + WDIOF_KEEPALIVEPING | + WDIOF_MAGICCLOSE, + .identity = "BCM63xx Watchdog", + }; + switch (cmd) { + case WDIOC_KEEPALIVE: + bcm63xx_wdt_reset(); + break; + case WDIOC_GETSTATUS: + case WDIOC_GETBOOTSTATUS: + value = bcm_readl(bcm63xx_wdt_device.regs + WDT_DEFVAL_REG); + if (copy_to_user(argp, &value, sizeof(int))) + return -EFAULT; + break; + case WDIOC_GETSUPPORT: + if (copy_to_user(argp, &ident, sizeof(ident))) + return -EFAULT; + break; + case WDIOC_SETOPTIONS: + if (copy_from_user(&value, argp, sizeof(int))) + return -EFAULT; + switch (value) { + case WDIOS_ENABLECARD: + bcm63xx_wdt_start(); + break; + case WDIOS_DISABLECARD: + bcm63xx_wdt_stop(); + default: + return -EINVAL; + } + break; + case WDIOC_SETTIMEOUT: + if (copy_from_user(&new_timeout, argp, sizeof(int))) + return -EFAULT; + if (new_timeout < 5) + return -EINVAL; + if (new_timeout > 40) + return -EINVAL; + bcm63xx_wdt_set(new_timeout); + bcm63xx_wdt_toggle(); + case WDIOC_GETTIMEOUT: + return copy_to_user(argp, &timeout, sizeof(int)); + default: + return -ENOTTY; + } + + return 0; +} + +static struct file_operations bcm63xx_wdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = bcm63xx_wdt_write, + .unlocked_ioctl = bcm63xx_wdt_ioctl, + .open = bcm63xx_wdt_open, + .release = bcm63xx_wdt_release, +}; + +static struct miscdevice bcm63xx_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &bcm63xx_wdt_fops, +}; + +static int bcm63xx_wdt_probe(struct platform_device *pdev) +{ + int ret; + struct resource *r; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!r) { + printk(KERN_ERR PFX + "failed to retrieve resources\n"); + return -ENODEV; + } + + bcm63xx_wdt_device.regs = ioremap_nocache(r->start, r->end - r->start); + if (!bcm63xx_wdt_device.regs) { + printk(KERN_ERR PFX + "failed to remap I/O resources\n"); + return -ENXIO; + } + + ret = misc_register(&bcm63xx_wdt_miscdev); + if (ret < 0) { + printk(KERN_ERR PFX + "failed to register watchdog device\n"); + goto unmap; + } + + init_completion(&bcm63xx_wdt_device.stop); + bcm63xx_wdt_device.queue = 0; + + clear_bit(0, &bcm63xx_wdt_device.inuse); + + setup_timer(&bcm63xx_wdt_device.timer, bcm63xx_wdt_update, 0L); + + bcm63xx_wdt_device.default_ticks = ticks; + bcm63xx_wdt_set(ticks); + bcm63xx_wdt_start(); + + printk(KERN_INFO PFX " started, timer margin: %d sec\n", WDT_INTERVAL); + + return 0; + +unmap: + iounmap(bcm63xx_wdt_device.regs); + return ret; +} + +static int bcm63xx_wdt_remove(struct platform_device *pdev) +{ + if (bcm63xx_wdt_device.queue) { + bcm63xx_wdt_device.queue = 0; + wait_for_completion(&bcm63xx_wdt_device.stop); + } + + misc_deregister(&bcm63xx_wdt_miscdev); + + iounmap(bcm63xx_wdt_device.regs); + + return 0; +} + +static struct platform_driver bcm63xx_wdt = { + .probe = bcm63xx_wdt_probe, + .remove = bcm63xx_wdt_remove, + .driver = { + .name = "bcm63xx-wdt", + } +}; + +static int __init bcm63xx_wdt_init(void) +{ + return platform_driver_register(&bcm63xx_wdt); +} + +static void __exit bcm63xx_wdt_exit(void) +{ + platform_driver_unregister(&bcm63xx_wdt); +} + +module_init(bcm63xx_wdt_init); +module_exit(bcm63xx_wdt_exit); + +MODULE_AUTHOR("Miguel Gaio <miguel.gaio@efixo.com>"); +MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>"); +MODULE_DESCRIPTION("Driver for the Broadcom BCM63xx SoC watchdog"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); +MODULE_ALIAS("platform:bcm63xx-wdt"); |