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Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0768-w1_therm-adding-ext_power-sysfs-entry.patch')
-rw-r--r--target/linux/bcm27xx/patches-5.4/950-0768-w1_therm-adding-ext_power-sysfs-entry.patch293
1 files changed, 0 insertions, 293 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0768-w1_therm-adding-ext_power-sysfs-entry.patch b/target/linux/bcm27xx/patches-5.4/950-0768-w1_therm-adding-ext_power-sysfs-entry.patch
deleted file mode 100644
index b2e8195b64..0000000000
--- a/target/linux/bcm27xx/patches-5.4/950-0768-w1_therm-adding-ext_power-sysfs-entry.patch
+++ /dev/null
@@ -1,293 +0,0 @@
-From 5737e27d3c5e2f743421e68f926c05e8581ae21f Mon Sep 17 00:00:00 2001
-From: Akira Shimahara <akira215corp@gmail.com>
-Date: Mon, 11 May 2020 22:36:50 +0200
-Subject: [PATCH] w1_therm: adding ext_power sysfs entry
-
-commit b7bb6ca17a90f47c2fe2848531b5bbaf27a65ba7 upstream.
-
-Adding ext_power sysfs entry (RO). Return the power status of the device:
- - 0: device parasite powered
- - 1: device externally powered
- - xx: xx is kernel error
-
-The power status of each device is check when the device is
-discover by the bus master, in 'w1_therm_add_slave(struct w1_slave *)'.
-The status is stored in the device structure w1_therm_family_data so
-that the driver always knows the power state of each device, which could
-be used later to determine the required strong pull up to apply on the
-line.
-
-The power status is re evaluate each time the sysfs ext_power read by
-a user.
-
-The hardware function 'read_powermode(struct w1_slave *sl)' act just as
-per device specifications, sending W1_READ_PSUPPLY command on the bus,
-and issue a read time slot, reading only one bit.
-
-A helper function 'bool bus_mutex_lock(struct mutex *lock)' is introduced.
-It try to aquire the bus mutex several times (W1_THERM_MAX_TRY), waiting
-W1_THERM_RETRY_DELAY between two attempt.
-
-Updating Documentation/ABI/testing/sysfs-driver-w1_therm accordingly.
-
-Signed-off-by: Akira Shimahara <akira215corp@gmail.com>
-Link: https://lore.kernel.org/r/20200511203650.410439-1-akira215corp@gmail.com
-Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
----
- .../ABI/testing/sysfs-driver-w1_therm | 29 ++++
- drivers/w1/slaves/w1_therm.c | 137 ++++++++++++++++++
- 2 files changed, 166 insertions(+)
- create mode 100644 Documentation/ABI/testing/sysfs-driver-w1_therm
-
---- /dev/null
-+++ b/Documentation/ABI/testing/sysfs-driver-w1_therm
-@@ -0,0 +1,29 @@
-+What: /sys/bus/w1/devices/.../ext_power
-+Date: May 2020
-+Contact: Akira Shimahara <akira215corp@gmail.com>
-+Description:
-+ (RO) return the power status by asking the device
-+ * '0': device parasite powered
-+ * '1': device externally powered
-+ * '-xx': xx is kernel error when reading power status
-+Users: any user space application which wants to communicate with
-+ w1_term device
-+
-+
-+What: /sys/bus/w1/devices/.../w1_slave
-+Date: May 2020
-+Contact: Akira Shimahara <akira215corp@gmail.com>
-+Description:
-+ (RW) return the temperature in 1/1000 degC.
-+ *read*: return 2 lines with the hexa output data sent on the
-+ bus, return the CRC check and temperature in 1/1000 degC
-+ *write* :
-+ * '0' : save the 2 or 3 bytes to the device EEPROM
-+ (i.e. TH, TL and config register)
-+ * '9..12' : set the device resolution in RAM
-+ (if supported)
-+ * Anything else: do nothing
-+ refer to Documentation/w1/slaves/w1_therm.rst for detailed
-+ information.
-+Users: any user space application which wants to communicate with
-+ w1_term device
-\ No newline at end of file
---- a/drivers/w1/slaves/w1_therm.c
-+++ b/drivers/w1/slaves/w1_therm.c
-@@ -43,8 +43,21 @@
- static int w1_strong_pullup = 1;
- module_param_named(strong_pullup, w1_strong_pullup, int, 0);
-
-+/* Nb of try for an operation */
-+#define W1_THERM_MAX_TRY 5
-+
-+/* ms delay to retry bus mutex */
-+#define W1_THERM_RETRY_DELAY 20
-+
- /* Helpers Macros */
-
-+/*
-+ * return the power mode of the sl slave : 1-ext, 0-parasite, <0 unknown
-+ * always test family data existence before using this macro
-+ */
-+#define SLAVE_POWERMODE(sl) \
-+ (((struct w1_therm_family_data *)(sl->family_data))->external_powered)
-+
- /* return the address of the refcnt in the family data */
- #define THERM_REFCNT(family_data) \
- (&((struct w1_therm_family_data *)family_data)->refcnt)
-@@ -73,10 +86,14 @@ struct w1_therm_family_converter {
- * struct w1_therm_family_data - device data
- * @rom: ROM device id (64bit Lasered ROM code + 1 CRC byte)
- * @refcnt: ref count
-+ * @external_powered: 1 device powered externally,
-+ * 0 device parasite powered,
-+ * -x error or undefined
- */
- struct w1_therm_family_data {
- uint8_t rom[9];
- atomic_t refcnt;
-+ int external_powered;
- };
-
- /**
-@@ -109,6 +126,20 @@ struct therm_info {
- */
- static int reset_select_slave(struct w1_slave *sl);
-
-+/**
-+ * read_powermode() - Query the power mode of the slave
-+ * @sl: slave to retrieve the power mode
-+ *
-+ * Ask the device to get its power mode (external or parasite)
-+ * and store the power status in the &struct w1_therm_family_data.
-+ *
-+ * Return:
-+ * * 0 parasite powered device
-+ * * 1 externally powered device
-+ * * <0 kernel error code
-+ */
-+static int read_powermode(struct w1_slave *sl);
-+
- /* Sysfs interface declaration */
-
- static ssize_t w1_slave_show(struct device *device,
-@@ -120,10 +151,14 @@ static ssize_t w1_slave_store(struct dev
- static ssize_t w1_seq_show(struct device *device,
- struct device_attribute *attr, char *buf);
-
-+static ssize_t ext_power_show(struct device *device,
-+ struct device_attribute *attr, char *buf);
-+
- /* Attributes declarations */
-
- static DEVICE_ATTR_RW(w1_slave);
- static DEVICE_ATTR_RO(w1_seq);
-+static DEVICE_ATTR_RO(ext_power);
-
- /* Interface Functions declaration */
-
-@@ -151,12 +186,14 @@ static void w1_therm_remove_slave(struct
-
- static struct attribute *w1_therm_attrs[] = {
- &dev_attr_w1_slave.attr,
-+ &dev_attr_ext_power.attr,
- NULL,
- };
-
- static struct attribute *w1_ds28ea00_attrs[] = {
- &dev_attr_w1_slave.attr,
- &dev_attr_w1_seq.attr,
-+ &dev_attr_ext_power.attr,
- NULL,
- };
-
-@@ -433,6 +470,34 @@ static struct w1_therm_family_converter
- /* Helpers Functions */
-
- /**
-+ * bus_mutex_lock() - Acquire the mutex
-+ * @lock: w1 bus mutex to acquire
-+ *
-+ * It try to acquire the mutex W1_THERM_MAX_TRY times and wait
-+ * W1_THERM_RETRY_DELAY between 2 attempts.
-+ *
-+ * Return: true is mutex is acquired and lock, false otherwise
-+ */
-+static inline bool bus_mutex_lock(struct mutex *lock)
-+{
-+ int max_trying = W1_THERM_MAX_TRY;
-+
-+ /* try to acquire the mutex, if not, sleep retry_delay before retry) */
-+ while (mutex_lock_interruptible(lock) != 0 && max_trying > 0) {
-+ unsigned long sleep_rem;
-+
-+ sleep_rem = msleep_interruptible(W1_THERM_RETRY_DELAY);
-+ if (!sleep_rem)
-+ max_trying--;
-+ }
-+
-+ if (!max_trying)
-+ return false; /* Didn't acquire the bus mutex */
-+
-+ return true;
-+}
-+
-+/**
- * w1_convert_temp() - temperature conversion binding function
- * @rom: data read from device RAM (8 data bytes + 1 CRC byte)
- * @fid: device family id
-@@ -461,7 +526,19 @@ static int w1_therm_add_slave(struct w1_
- GFP_KERNEL);
- if (!sl->family_data)
- return -ENOMEM;
-+
- atomic_set(THERM_REFCNT(sl->family_data), 1);
-+
-+ /* Getting the power mode of the device {external, parasite} */
-+ SLAVE_POWERMODE(sl) = read_powermode(sl);
-+
-+ if (SLAVE_POWERMODE(sl) < 0) {
-+ /* no error returned as device has been added */
-+ dev_warn(&sl->dev,
-+ "%s: Device has been added, but power_mode may be corrupted. err=%d\n",
-+ __func__, SLAVE_POWERMODE(sl));
-+ }
-+
- return 0;
- }
-
-@@ -661,6 +738,44 @@ error:
- return ret;
- }
-
-+static int read_powermode(struct w1_slave *sl)
-+{
-+ struct w1_master *dev_master = sl->master;
-+ int max_trying = W1_THERM_MAX_TRY;
-+ int ret = -ENODEV;
-+
-+ if (!sl->family_data)
-+ goto error;
-+
-+ /* prevent the slave from going away in sleep */
-+ atomic_inc(THERM_REFCNT(sl->family_data));
-+
-+ if (!bus_mutex_lock(&dev_master->bus_mutex)) {
-+ ret = -EAGAIN; /* Didn't acquire the mutex */
-+ goto dec_refcnt;
-+ }
-+
-+ while ((max_trying--) && (ret < 0)) {
-+ /* safe version to select slave */
-+ if (!reset_select_slave(sl)) {
-+ w1_write_8(dev_master, W1_READ_PSUPPLY);
-+ /*
-+ * Emit a read time slot and read only one bit,
-+ * 1 is externally powered,
-+ * 0 is parasite powered
-+ */
-+ ret = w1_touch_bit(dev_master, 1);
-+ /* ret should be either 1 either 0 */
-+ }
-+ }
-+ mutex_unlock(&dev_master->bus_mutex);
-+
-+dec_refcnt:
-+ atomic_dec(THERM_REFCNT(sl->family_data));
-+error:
-+ return ret;
-+}
-+
- /* Sysfs Interface definition */
-
- static ssize_t w1_slave_show(struct device *device,
-@@ -722,6 +837,28 @@ static ssize_t w1_slave_store(struct dev
- return ret ? : size;
- }
-
-+static ssize_t ext_power_show(struct device *device,
-+ struct device_attribute *attr, char *buf)
-+{
-+ struct w1_slave *sl = dev_to_w1_slave(device);
-+
-+ if (!sl->family_data) {
-+ dev_info(device,
-+ "%s: Device not supported by the driver\n", __func__);
-+ return 0; /* No device family */
-+ }
-+
-+ /* Getting the power mode of the device {external, parasite} */
-+ SLAVE_POWERMODE(sl) = read_powermode(sl);
-+
-+ if (SLAVE_POWERMODE(sl) < 0) {
-+ dev_dbg(device,
-+ "%s: Power_mode may be corrupted. err=%d\n",
-+ __func__, SLAVE_POWERMODE(sl));
-+ }
-+ return sprintf(buf, "%d\n", SLAVE_POWERMODE(sl));
-+}
-+
- #if IS_REACHABLE(CONFIG_HWMON)
- static int w1_read_temp(struct device *device, u32 attr, int channel,
- long *val)
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-23 04:11:13 +0000