Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966416AbbLQMYq (ORCPT ); Thu, 17 Dec 2015 07:24:46 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42102 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966088AbbLQMYn (ORCPT ); Thu, 17 Dec 2015 07:24:43 -0500 From: Pratyush Anand To: wim@iguana.be Cc: dyoung@redhat.com, dzickus@redhat.com, linux@roeck-us.net, linux-watchdog@vger.kernel.org, Pratyush Anand , linux-api@vger.kernel.org (open list:ABI/API), linux-kernel@vger.kernel.org (open list) Subject: [PATCH V5 2/2] watchdog: Read device status through sysfs attributes Date: Thu, 17 Dec 2015 17:53:59 +0530 Message-Id: In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7990 Lines: 270 This patch adds following attributes to watchdog device's sysfs interface to read its different status. * state - reads whether device is active or not * identity - reads Watchdog device's identity string. * timeout - reads current 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 nowayout power state subsystem timeleft timeout uevent # cat identity iTCO_wdt # cat timeout 30 # cat state inactive # echo > /dev/watchdog1 # cat timeleft 26 # cat state active # cat bootstatus 0 # cat nowayout 0 Signed-off-by: Pratyush Anand Reviewed-by: Guenter Roeck --- Documentation/ABI/testing/sysfs-class-watchdog | 51 +++++++++++ drivers/watchdog/Kconfig | 7 ++ drivers/watchdog/watchdog_core.c | 2 +- drivers/watchdog/watchdog_dev.c | 114 +++++++++++++++++++++++++ 4 files changed, 173 insertions(+), 1 deletion(-) 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..736046b33040 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-watchdog @@ -0,0 +1,51 @@ +What: /sys/class/watchdog/watchdogn/bootstatus +Date: August 2015 +Contact: Wim Van Sebroeck +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: Wim Van Sebroeck +Description: + It is a read only file. It contains identity string of + watchdog device. + +What: /sys/class/watchdog/watchdogn/nowayout +Date: August 2015 +Contact: Wim Van Sebroeck +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/state +Date: August 2015 +Contact: Wim Van Sebroeck +Description: + It is a read only file. It gives active/inactive status of + watchdog device. + +What: /sys/class/watchdog/watchdogn/status +Date: August 2015 +Contact: Wim Van Sebroeck +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: Wim Van Sebroeck +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: Wim Van Sebroeck +Description: + It is a read only file. It is read to know about current + value of timeout programmed. diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 1c427beffadd..71e47dde7d4a 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -46,6 +46,13 @@ config WATCHDOG_NOWAYOUT get killed. If you say Y here, the watchdog cannot be stopped once it has been started. +config WATCHDOG_SYSFS + bool "Read different watchdog information through sysfs" + default n + help + Say Y here if you want to enable watchdog device status read through + sysfs attributes. + # # General Watchdog drivers # diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c index a55e846eec79..62f4496b7975 100644 --- a/drivers/watchdog/watchdog_core.c +++ b/drivers/watchdog/watchdog_core.c @@ -194,7 +194,7 @@ 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, "watchdog%d", wdd->id); if (IS_ERR(wdd->dev)) { watchdog_dev_unregister(wdd); ida_simple_remove(&watchdog_ida, id); diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c index 055a4e1b4c13..d93118e97d11 100644 --- a/drivers/watchdog/watchdog_dev.c +++ b/drivers/watchdog/watchdog_dev.c @@ -247,6 +247,117 @@ out_timeleft: return err; } +#ifdef CONFIG_WATCHDOG_SYSFS +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 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); + + return sprintf(buf, "%u\n", wdd->bootstatus); +} +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_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 umode_t wdt_is_visible(struct kobject *kobj, struct attribute *attr, + int n) +{ + struct device *dev = container_of(kobj, struct device, kobj); + struct watchdog_device *wdd = dev_get_drvdata(dev); + umode_t mode = attr->mode; + + if (attr == &dev_attr_status.attr && !wdd->ops->status) + mode = 0; + else if (attr == &dev_attr_timeleft.attr && !wdd->ops->get_timeleft) + mode = 0; + + return mode; +} +static struct attribute *wdt_attrs[] = { + &dev_attr_state.attr, + &dev_attr_identity.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, + .is_visible = wdt_is_visible, +}; +__ATTRIBUTE_GROUPS(wdt); +#endif + /* * watchdog_ioctl_op: call the watchdog drivers ioctl op if defined * @wdd: the watchdog device to do the ioctl on @@ -584,6 +695,9 @@ int watchdog_dev_unregister(struct watchdog_device *wdd) static struct class watchdog_class = { .name = "watchdog", .owner = THIS_MODULE, +#ifdef CONFIG_WATCHDOG_SYSFS + .dev_groups = wdt_groups, +#endif }; /* -- 2.5.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/