On 12/8/19 10:45 AM, harshal chaudhari wrote:
Hi Wim and Guenter, This patch adds following attributes to GPIO-controlled watchdog device's sysfs interface to read its different status.
You lost me. What does this patch do that CONFIG_WATCHDOG_SYSFS doesn't do as well ? Guenter
* state - reads whether device is active or not * identity - reads Watchdog device's identity string. * timeout - reads current timeout. * bootstatus - reads status of the watchdog device at boot. * nowayout - reads whether nowayout feature was set or not. Testing with GPIO Watchdog: $ cat bootstatus 0 $ cat identity GPIO Watchdog $ cat nowayout 0 $ cat state inactive $ cat timeout 60 Signed-off-by: harshal chaudhari <harshalchau04@xxxxxxxxx <mailto:harshalchau04@xxxxxxxxx>> diff --git a/Documentation/devicetree/bindings/watchdog/gpio-wdt.txt b/Documentation/devicetree/bindings/watchdog/gpio-wdt.txt index 198794963786..762149375280 100644 --- a/Documentation/devicetree/bindings/watchdog/gpio-wdt.txt +++ b/Documentation/devicetree/bindings/watchdog/gpio-wdt.txt @@ -26,3 +26,31 @@ Example: hw_algo = "toggle"; hw_margin_ms = <1600>; }; + + +* Read device status through sysfs attributes + + state - reads whether device is active or not + + It is a read only file. It gives active/inactive status of + watchdog device. + + identity - reads Watchdog device's identity string. + + It is a read only file. It contains identity string of + watchdog device. + + timeout - reads current timeout. + It is a read only file. It is read to know about current + value of timeout programmed. + + bootstatus - reads status of the watchdog device at boot + It is a read only file. It contains status of the watchdog + device at boot. It is equivalent to WDIOC_GETBOOTSTATUS of + ioctl interface. + + nowayout - reads whether nowayout feature was set or not + It is a read only file. While reading, it gives '1' if that + device supports nowayout feature else, it gives '0'. + +For more details refer the documents as in Documentation/ABI/testing/sysfs-class-watchdog diff --git a/drivers/watchdog/gpio_wdt.c b/drivers/watchdog/gpio_wdt.c index 0923201ce874..d49eb77ec8f1 100644 --- a/drivers/watchdog/gpio_wdt.c +++ b/drivers/watchdog/gpio_wdt.c @@ -90,6 +90,68 @@ static int gpio_wdt_stop(struct watchdog_device *wdd) return 0; } +static ssize_t timeout_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct watchdog_device *wdd = dev_get_drvdata(dev); + + return sprintf(buf, "%u\n", wdd->timeout); +} +static DEVICE_ATTR_RO(timeout); + +static ssize_t identity_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct watchdog_device *wdd = dev_get_drvdata(dev); + + return sprintf(buf, "%s\n", wdd->info->identity); +} +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); + + if (watchdog_active(wdd)) + return sprintf(buf, "active\n"); + + return sprintf(buf, "inactive\n"); +} +static DEVICE_ATTR_RO(state); + +static ssize_t bootstatus_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct watchdog_device *wdd = dev_get_drvdata(dev); + + return sprintf(buf, "%u\n", wdd->bootstatus); +} +static DEVICE_ATTR_RO(bootstatus); + +static ssize_t nowayout_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct watchdog_device *wdd = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", !!test_bit(WDOG_NO_WAY_OUT, &wdd->status)); +} +static DEVICE_ATTR_RO(nowayout); + +static struct attribute *wdt_attrs[] = { + &dev_attr_state.attr, + &dev_attr_identity.attr, + &dev_attr_timeout.attr, + &dev_attr_bootstatus.attr, + &dev_attr_nowayout.attr, + NULL, +}; + +static const struct attribute_group wdt_group = { + .attrs = wdt_attrs, +}; +__ATTRIBUTE_GROUPS(wdt); + static const struct watchdog_info gpio_wdt_ident = { .options = WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT, @@ -155,6 +217,7 @@ static int gpio_wdt_probe(struct platform_device *pdev) priv->wdd.max_hw_heartbeat_ms = hw_margin; priv->wdd.parent = dev; priv->wdd.timeout = SOFT_TIMEOUT_DEF; + priv->wdd.groups = wdt_groups; watchdog_init_timeout(&priv->wdd, 0, dev); watchdog_set_nowayout(&priv->wdd, nowayout);
