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-rw-r--r--target/linux/bcm27xx/patches-5.4/950-0772-w1_therm-adding-alarm-sysfs-entry.patch319
1 files changed, 319 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0772-w1_therm-adding-alarm-sysfs-entry.patch b/target/linux/bcm27xx/patches-5.4/950-0772-w1_therm-adding-alarm-sysfs-entry.patch
new file mode 100644
index 0000000000..f4b8d5d1d6
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.4/950-0772-w1_therm-adding-alarm-sysfs-entry.patch
@@ -0,0 +1,319 @@
+From 8c3d9356c3c3b9c9188f1e192c7e2541e313c7ab Mon Sep 17 00:00:00 2001
+From: Akira Shimahara <akira215corp@gmail.com>
+Date: Mon, 11 May 2020 22:38:01 +0200
+Subject: [PATCH] w1_therm: adding alarm sysfs entry
+
+commit e2c94d6f572079511945e64537eb1218643f2e68 upstream.
+
+Adding device alarms settings by a dedicated sysfs entry alarms (RW):
+read or write TH and TL in the device RAM. Checking devices in alarm
+state could be performed using the master search command.
+
+As alarms temperature level are store in a 8 bit register on the device
+and are signed values, a safe cast shall be performed using the min and
+max temperature that device are able to measure. This is done by
+int_to_short inline function.
+
+A 'write_data' field is added in the device structure, to bind the
+correct writing function, as some devices may have 2 or 3 bytes RAM.
+
+Updating Documentation/ABI/testing/sysfs-driver-w1_therm accordingly.
+
+Signed-off-by: Akira Shimahara <akira215corp@gmail.com>
+Link: https://lore.kernel.org/r/20200511203801.411253-1-akira215corp@gmail.com
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ .../ABI/testing/sysfs-driver-w1_therm | 16 ++
+ drivers/w1/slaves/w1_therm.c | 161 ++++++++++++++++++
+ 2 files changed, 177 insertions(+)
+
+--- a/Documentation/ABI/testing/sysfs-driver-w1_therm
++++ b/Documentation/ABI/testing/sysfs-driver-w1_therm
+@@ -1,3 +1,19 @@
++What: /sys/bus/w1/devices/.../alarms
++Date: May 2020
++Contact: Akira Shimahara <akira215corp@gmail.com>
++Description:
++ (RW) read or write TH and TL (Temperature High an Low) alarms.
++ Values shall be space separated and in the device range
++ (typical -55 degC to 125 degC), if not values will be trimmed
++ to device min/max capabilities. Values are integer as they are
++ stored in a 8bit register in the device. Lowest value is
++ automatically put to TL. Once set, alarms could be search at
++ master level, refer to Documentation/w1/w1_generic.rst for
++ detailed information
++Users: any user space application which wants to communicate with
++ w1_term device
++
++
+ What: /sys/bus/w1/devices/.../eeprom
+ Date: May 2020
+ Contact: Akira Shimahara <akira215corp@gmail.com>
+--- a/drivers/w1/slaves/w1_therm.c
++++ b/drivers/w1/slaves/w1_therm.c
+@@ -58,6 +58,9 @@ module_param_named(strong_pullup, w1_str
+ #define EEPROM_CMD_WRITE "save" /* cmd for write eeprom sysfs */
+ #define EEPROM_CMD_READ "restore" /* cmd for read eeprom sysfs */
+
++#define MIN_TEMP -55 /* min temperature that can be mesured */
++#define MAX_TEMP 125 /* max temperature that can be mesured */
++
+ /* Helpers Macros */
+
+ /*
+@@ -96,6 +99,7 @@ module_param_named(strong_pullup, w1_str
+ * @get_conversion_time: pointer to the device conversion time function
+ * @set_resolution: pointer to the device set_resolution function
+ * @get_resolution: pointer to the device get_resolution function
++ * @write_data: pointer to the device writing function (2 or 3 bytes)
+ */
+ struct w1_therm_family_converter {
+ u8 broken;
+@@ -105,6 +109,7 @@ struct w1_therm_family_converter {
+ int (*get_conversion_time)(struct w1_slave *sl);
+ int (*set_resolution)(struct w1_slave *sl, int val);
+ int (*get_resolution)(struct w1_slave *sl);
++ int (*write_data)(struct w1_slave *sl, const u8 *data);
+ };
+
+ /**
+@@ -239,6 +244,12 @@ static ssize_t resolution_store(struct d
+ static ssize_t eeprom_store(struct device *device,
+ struct device_attribute *attr, const char *buf, size_t size);
+
++static ssize_t alarms_store(struct device *device,
++ struct device_attribute *attr, const char *buf, size_t size);
++
++static ssize_t alarms_show(struct device *device,
++ struct device_attribute *attr, char *buf);
++
+ /* Attributes declarations */
+
+ static DEVICE_ATTR_RW(w1_slave);
+@@ -247,6 +258,7 @@ static DEVICE_ATTR_RO(temperature);
+ static DEVICE_ATTR_RO(ext_power);
+ static DEVICE_ATTR_RW(resolution);
+ static DEVICE_ATTR_WO(eeprom);
++static DEVICE_ATTR_RW(alarms);
+
+ /* Interface Functions declaration */
+
+@@ -278,6 +290,7 @@ static struct attribute *w1_therm_attrs[
+ &dev_attr_ext_power.attr,
+ &dev_attr_resolution.attr,
+ &dev_attr_eeprom.attr,
++ &dev_attr_alarms.attr,
+ NULL,
+ };
+
+@@ -286,6 +299,7 @@ static struct attribute *w1_ds18s20_attr
+ &dev_attr_temperature.attr,
+ &dev_attr_ext_power.attr,
+ &dev_attr_eeprom.attr,
++ &dev_attr_alarms.attr,
+ NULL,
+ };
+
+@@ -296,6 +310,7 @@ static struct attribute *w1_ds28ea00_att
+ &dev_attr_ext_power.attr,
+ &dev_attr_resolution.attr,
+ &dev_attr_eeprom.attr,
++ &dev_attr_alarms.attr,
+ NULL,
+ };
+
+@@ -556,6 +571,7 @@ static struct w1_therm_family_converter
+ .get_conversion_time = w1_DS18S20_convert_time,
+ .set_resolution = NULL, /* no config register */
+ .get_resolution = NULL, /* no config register */
++ .write_data = w1_DS18S20_write_data,
+ },
+ {
+ .f = &w1_therm_family_DS1822,
+@@ -563,6 +579,7 @@ static struct w1_therm_family_converter
+ .get_conversion_time = w1_DS18B20_convert_time,
+ .set_resolution = w1_DS18B20_set_resolution,
+ .get_resolution = w1_DS18B20_get_resolution,
++ .write_data = w1_DS18B20_write_data,
+ },
+ {
+ .f = &w1_therm_family_DS18B20,
+@@ -570,6 +587,7 @@ static struct w1_therm_family_converter
+ .get_conversion_time = w1_DS18B20_convert_time,
+ .set_resolution = w1_DS18B20_set_resolution,
+ .get_resolution = w1_DS18B20_get_resolution,
++ .write_data = w1_DS18B20_write_data,
+ },
+ {
+ .f = &w1_therm_family_DS28EA00,
+@@ -577,6 +595,7 @@ static struct w1_therm_family_converter
+ .get_conversion_time = w1_DS18B20_convert_time,
+ .set_resolution = w1_DS18B20_set_resolution,
+ .get_resolution = w1_DS18B20_get_resolution,
++ .write_data = w1_DS18B20_write_data,
+ },
+ {
+ .f = &w1_therm_family_DS1825,
+@@ -584,6 +603,7 @@ static struct w1_therm_family_converter
+ .get_conversion_time = w1_DS18B20_convert_time,
+ .set_resolution = w1_DS18B20_set_resolution,
+ .get_resolution = w1_DS18B20_get_resolution,
++ .write_data = w1_DS18B20_write_data,
+ }
+ };
+
+@@ -678,6 +698,26 @@ static inline int temperature_from_RAM(s
+ return 0; /* No device family */
+ }
+
++/**
++ * int_to_short() - Safe casting of int to short
++ *
++ * @i: integer to be converted to short
++ *
++ * Device register use 1 byte to store signed integer.
++ * This helper function convert the int in a signed short,
++ * using the min/max values that device can measure as limits.
++ * min/max values are defined by macro.
++ *
++ * Return: a short in the range of min/max value
++ */
++static inline s8 int_to_short(int i)
++{
++ /* Prepare to cast to short by eliminating out of range values */
++ i = i > MAX_TEMP ? MAX_TEMP : i;
++ i = i < MIN_TEMP ? MIN_TEMP : i;
++ return (s8) i;
++}
++
+ /* Interface Functions */
+
+ static int w1_therm_add_slave(struct w1_slave *sl)
+@@ -1250,6 +1290,127 @@ static ssize_t eeprom_store(struct devic
+
+ return size;
+ }
++
++static ssize_t alarms_show(struct device *device,
++ struct device_attribute *attr, char *buf)
++{
++ struct w1_slave *sl = dev_to_w1_slave(device);
++ int ret = -ENODEV;
++ s8 th = 0, tl = 0;
++ struct therm_info scratchpad;
++
++ ret = read_scratchpad(sl, &scratchpad);
++
++ if (!ret) {
++ th = scratchpad.rom[2]; /* TH is byte 2 */
++ tl = scratchpad.rom[3]; /* TL is byte 3 */
++ } else {
++ dev_info(device,
++ "%s: error reading alarms register %d\n",
++ __func__, ret);
++ }
++
++ return sprintf(buf, "%hd %hd\n", tl, th);
++}
++
++static ssize_t alarms_store(struct device *device,
++ struct device_attribute *attr, const char *buf, size_t size)
++{
++ struct w1_slave *sl = dev_to_w1_slave(device);
++ struct therm_info info;
++ u8 new_config_register[3]; /* array of data to be written */
++ int temp, ret = -EINVAL;
++ char *token = NULL;
++ s8 tl, th, tt; /* 1 byte per value + temp ring order */
++ char *p_args = kmalloc(size, GFP_KERNEL);
++
++ /* Safe string copys as buf is const */
++ if (!p_args) {
++ dev_warn(device,
++ "%s: error unable to allocate memory %d\n",
++ __func__, -ENOMEM);
++ return size;
++ }
++ strcpy(p_args, buf);
++
++ /* Split string using space char */
++ token = strsep(&p_args, " ");
++
++ if (!token) {
++ dev_info(device,
++ "%s: error parsing args %d\n", __func__, -EINVAL);
++ goto free_m;
++ }
++
++ /* Convert 1st entry to int */
++ ret = kstrtoint (token, 10, &temp);
++ if (ret) {
++ dev_info(device,
++ "%s: error parsing args %d\n", __func__, ret);
++ goto free_m;
++ }
++
++ tl = int_to_short(temp);
++
++ /* Split string using space char */
++ token = strsep(&p_args, " ");
++ if (!token) {
++ dev_info(device,
++ "%s: error parsing args %d\n", __func__, -EINVAL);
++ goto free_m;
++ }
++ /* Convert 2nd entry to int */
++ ret = kstrtoint (token, 10, &temp);
++ if (ret) {
++ dev_info(device,
++ "%s: error parsing args %d\n", __func__, ret);
++ goto free_m;
++ }
++
++ /* Prepare to cast to short by eliminating out of range values */
++ th = int_to_short(temp);
++
++ /* Reorder if required th and tl */
++ if (tl > th) {
++ tt = tl; tl = th; th = tt;
++ }
++
++ /*
++ * Read the scratchpad to change only the required bits
++ * (th : byte 2 - tl: byte 3)
++ */
++ ret = read_scratchpad(sl, &info);
++ if (!ret) {
++ new_config_register[0] = th; /* Byte 2 */
++ new_config_register[1] = tl; /* Byte 3 */
++ new_config_register[2] = info.rom[4];/* Byte 4 */
++ } else {
++ dev_info(device,
++ "%s: error reading from the slave device %d\n",
++ __func__, ret);
++ goto free_m;
++ }
++
++ /* Write data in the device RAM */
++ if (!SLAVE_SPECIFIC_FUNC(sl)) {
++ dev_info(device,
++ "%s: Device not supported by the driver %d\n",
++ __func__, -ENODEV);
++ goto free_m;
++ }
++
++ ret = SLAVE_SPECIFIC_FUNC(sl)->write_data(sl, new_config_register);
++ if (ret)
++ dev_info(device,
++ "%s: error writing to the slave device %d\n",
++ __func__, ret);
++
++free_m:
++ /* free allocated memory */
++ kfree(p_args);
++
++ return size;
++}
+
+ #if IS_REACHABLE(CONFIG_HWMON)
+ static int w1_read_temp(struct device *device, u32 attr, int channel,