This patch adds following attributes to watchdog device's sysfs interface.
* start - writes non zero value to start and zero to stop
* state - reads whether device is active or not(1 for active and 0 for
inactive)
* identity - reads Watchdog device's identity string.
* keepalive - writes to ping a watchdog device
* timeout - reads current timeout and writes to program a new timeout.
* timeleft - reads timeleft before watchdog generates a reset
* bootstatus - reads status of the watchdog device at boot
* status - reads watchdog device's internal status bits
* nowayout - reads whether nowayout feature was set or not
Testing with iTCO_wdt:
# cd /sys/class/watchdog/watchdog1/
# ls
bootstatus dev device identity keepalive nowayout power start state
status subsystem timeleft timeout uevent
# cat identity
iTCO_wdt
# cat timeout
30
# echo 1 > start
# cat timeleft
26
# echo 120 > timeout
# cat timeleft
116
# echo > keepalive
# cat timeleft
118
# cat state
1
# echo 0 > start
# cat state
0
# cat bootstatus
0
# cat nowayout
0
# cat status
cat: status: Operation not supported
Signed-off-by: Pratyush Anand <panand@xxxxxxxxxx>
---
Documentation/ABI/testing/sysfs-class-watchdog | 74 +++++++++
drivers/watchdog/watchdog_core.c | 6 +-
drivers/watchdog/watchdog_core.h | 2 +
drivers/watchdog/watchdog_dev.c | 206 +++++++++++++++++++++++++
4 files changed, 284 insertions(+), 4 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-class-watchdog
diff --git a/Documentation/ABI/testing/sysfs-class-watchdog b/Documentation/ABI/testing/sysfs-class-watchdog
new file mode 100644
index 000000000000..31e7be53edf8
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-watchdog
@@ -0,0 +1,74 @@
+What: /sys/class/watchdog/watchdogn/bootstatus
+Date: August 2015
+Contact: Pratyush Anand <panand@xxxxxxxxxx>
+Description:
+ It is a read only file. It contains status of the watchdog
+ device at boot. It is equivalent to WDIOC_GETBOOTSTATUS of
+ ioctl interface.
+
+What: /sys/class/watchdog/watchdogn/identity
+Date: August 2015
+Contact: Pratyush Anand <panand@xxxxxxxxxx>
+Description:
+ It is a read only file. It contains identity string of
+ watchdog device.
+
+What: /sys/class/watchdog/watchdogn/keepalive
+Date: August 2015
+Contact: Pratyush Anand <panand@xxxxxxxxxx>
+Description:
+ It is a write only file. It is written to ping a watchdog
+ device to keep it alive. It is equivalent to
+ WDIOC_KEEPALIVE of ioctl interface.
+
+What: /sys/class/watchdog/watchdogn/nowayout
+Date: August 2015
+Contact: Pratyush Anand <panand@xxxxxxxxxx>
+Description:
+ It is a read only file. While reading, it gives '1' if that
+ device supports nowayout feature else, it gives '0'.
+
+What: /sys/class/watchdog/watchdogn/start
+Date: August 2015
+Contact: Pratyush Anand <panand@xxxxxxxxxx>
+Description:
+ It is a write only file. Writing '1' will trigger that
+ watchdog device and writing '0' will stop it. These are
+ equivalent to WDIOS_ENABLECARD and WDIOS_DISABLECARD of ioctl
+ interface. If a device has nowayout programmed, then that
+ can not be stopped. Therefore, it is recommended to read
+ state file to insure that whether watchdog device was
+ stopped or not after writing '0'.
+
+What: /sys/class/watchdog/watchdogn/state
+Date: August 2015
+Contact: Pratyush Anand <panand@xxxxxxxxxx>
+Description:
+ It is a read only file. If it is read as '1' then a watchdog
+ device is active. If it is read as '0' then a watchdog
+ device is inactive.
+
+What: /sys/class/watchdog/watchdogn/status
+Date: August 2015
+Contact: Pratyush Anand <panand@xxxxxxxxxx>
+Description:
+ It is a read only file. It contains watchdog device's
+ internal status bits. It is equivalent to WDIOC_GETSTATUS
+ of ioctl interface.
+
+What: /sys/class/watchdog/watchdogn/timeleft
+Date: August 2015
+Contact: Pratyush Anand <panand@xxxxxxxxxx>
+Description:
+ It is a read only file. It contains value of time left for
+ reset generation. It is equivalent to WDIOC_GETTIMELEFT of
+ ioctl interface.
+
+What: /sys/class/watchdog/watchdogn/timeout
+Date: August 2015
+Contact: Pratyush Anand <panand@xxxxxxxxxx>
+Description:
+ It is a read/write file. It is read to know about current
+ timeout and written to program a new timeout value. These
+ are equivalent to WDIOC_SETTIMEOUT and WDIOC_GETTIMEOUT of
+ ioctl interface.
diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c
index 1a8059455413..703ff7b23f31 100644
--- a/drivers/watchdog/watchdog_core.c
+++ b/drivers/watchdog/watchdog_core.c
@@ -139,7 +139,7 @@ EXPORT_SYMBOL_GPL(watchdog_init_timeout);
static int __watchdog_register_device(struct watchdog_device *wdd)
{
- int ret, id, devno;
+ int ret, id;
if (wdd == NULL || wdd->info == NULL || wdd->ops == NULL)
return -EINVAL;
@@ -181,9 +181,7 @@ static int __watchdog_register_device(struct watchdog_device *wdd)
}
}
- devno = wdd->cdev.dev;
- wdd->dev = device_create(watchdog_class, wdd->parent, devno,
- NULL, "watchdog%d", wdd->id);
+ wdd->dev = watchdog_device_create(watchdog_class, wdd);
if (IS_ERR(wdd->dev)) {
watchdog_dev_unregister(wdd);
ida_simple_remove(&watchdog_ida, id);
diff --git a/drivers/watchdog/watchdog_core.h b/drivers/watchdog/watchdog_core.h
index 6c951418fca7..36abd15ffcea 100644
--- a/drivers/watchdog/watchdog_core.h
+++ b/drivers/watchdog/watchdog_core.h
@@ -31,6 +31,8 @@
/*
* Functions/procedures to be called by the core
*/
+struct device * watchdog_device_create(struct class *,
+ struct watchdog_device *);
extern int watchdog_dev_register(struct watchdog_device *);
extern int watchdog_dev_unregister(struct watchdog_device *);
extern int __init watchdog_dev_init(void);
diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index 6aaefbad303e..1186b5a918e9 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -248,6 +248,212 @@ out_timeleft:
return err;
}
+static ssize_t nowayout_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ bool nowayout = false;
+
+ mutex_lock(&wdd->lock);
+ if (test_bit(WDOG_NO_WAY_OUT, &wdd->status))
+ nowayout = true;
+ mutex_unlock(&wdd->lock);
+
+ return sprintf(buf, "%d\n", nowayout);
+}
+static DEVICE_ATTR_RO(nowayout);
+
+static ssize_t status_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ ssize_t status;
+ unsigned int val;
+
+ status = watchdog_get_status(wdd, &val);
+ if (!status)
+ status = sprintf(buf, "%u\n", val);
+
+ return status;
+}
+static DEVICE_ATTR_RO(status);
+
+static ssize_t bootstatus_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ ssize_t status;
+
+ mutex_lock(&wdd->lock);
+ status = sprintf(buf, "%u\n", wdd->bootstatus);
+ mutex_unlock(&wdd->lock);
+
+ return status;
+}
+static DEVICE_ATTR_RO(bootstatus);
+
+static ssize_t timeleft_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ ssize_t status;
+ unsigned int val;
+
+ status = watchdog_get_timeleft(wdd, &val);
+
+ if (!status)
+ status = sprintf(buf, "%u\n", val);
+
+ return status;
+}
+static DEVICE_ATTR_RO(timeleft);
+
+static ssize_t timeout_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t size)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ unsigned int val;
+ ssize_t status = 0;
+
+ status = kstrtouint(buf, 0, &val);
+ if (!status) {
+ status = watchdog_set_timeout(wdd, val);
+ if (status >= 0)
+ status = watchdog_ping(wdd);
+ }
+
+ if (status < 0)
+ return status;
+ else
+ return size;
+}
+
+static ssize_t timeout_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ ssize_t status;
+
+ mutex_lock(&wdd->lock);
+ if (wdd->timeout == 0)
+ status = -EOPNOTSUPP;
+ else
+ status = sprintf(buf, "%u\n", wdd->timeout);
+ mutex_unlock(&wdd->lock);
+
+ return status;
+}
+static DEVICE_ATTR_RW(timeout);
+
+static ssize_t keepalive_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t size)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ ssize_t status = 0;
+
+ mutex_lock(&wdd->lock);
+ if (!(wdd->info->options & WDIOF_KEEPALIVEPING))
+ status = -EOPNOTSUPP;
+ mutex_unlock(&wdd->lock);
+
+ if (!status)
+ status = watchdog_ping(wdd);
+
+ if (status < 0)
+ return status;
+ else
+ return size;
+}
+static DEVICE_ATTR_WO(keepalive);
+
+static ssize_t identity_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ ssize_t status;
+
+ mutex_lock(&wdd->lock);
+ status = sprintf(buf, "%s\n", wdd->info->identity);
+ mutex_unlock(&wdd->lock);
+
+ return status;
+}
+static DEVICE_ATTR_RO(identity);
+
+static ssize_t state_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ bool active;
+
+ mutex_lock(&wdd->lock);
+ active = watchdog_active(wdd);
+ mutex_unlock(&wdd->lock);
+
+ return sprintf(buf, "%d\n", active);
+}
+static DEVICE_ATTR_RO(state);
+
+static ssize_t start_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t size)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ ssize_t status = 0;
+ unsigned int val;
+
+ status = kstrtouint(buf, 0, &val);
+ if (status)
+ return status;
+ if (val)
+ status = watchdog_start(wdd);
+ else
+ status = watchdog_stop(wdd);
+
+ if (status < 0)
+ return status;
+ else
+ return size;
+}
+static DEVICE_ATTR_WO(start);
+
+static struct attribute *wdt_attrs[] = {
+ &dev_attr_start.attr,
+ &dev_attr_state.attr,
+ &dev_attr_identity.attr,
+ &dev_attr_keepalive.attr,
+ &dev_attr_timeout.attr,
+ &dev_attr_timeleft.attr,
+ &dev_attr_bootstatus.attr,
+ &dev_attr_status.attr,
+ &dev_attr_nowayout.attr,
+ NULL,
+};
+
+static const struct attribute_group wdt_group = {
+ .attrs = wdt_attrs,
+};
+
+static const struct attribute_group *wdt_groups[] = {
+ &wdt_group,
+ NULL
+};
+
+/*
+ * watchdog_device_create: create a struct device for a given watchdog
+ * device
+ * @wdc: watchdog class with which created device is associated
+ * @wdd: watchdog device
+ *
+ * Creates a struct device corresponding to given watchdog device and
+ * associates a device attribute_group with it.
+ */
+struct device * watchdog_device_create(struct class *wdc,
+ struct watchdog_device *wdd)
+{
+ return device_create_with_groups(wdc, wdd->parent, wdd->cdev.dev,
+ wdd, wdt_groups, "watchdog%d", wdd->id);
+}
+
/*
* watchdog_ioctl_op: call the watchdog drivers ioctl op if defined
* @wddev: the watchdog device to do the ioctl on
--
2.4.3
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