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[108.223.40.66]) by mx.google.com with ESMTPSA id hb10sm10645058pbd.75.2014.05.15.13.38.39 for (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Thu, 15 May 2014 13:38:40 -0700 (PDT) From: Guenter Roeck To: linux-watchdog@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 1/6] watchdog: Add API to trigger reboots Date: Thu, 15 May 2014 13:38:19 -0700 Message-Id: <1400186304-1691-2-git-send-email-linux@roeck-us.net> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1400186304-1691-1-git-send-email-linux@roeck-us.net> References: <1400186304-1691-1-git-send-email-linux@roeck-us.net> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140515_133901_939906_684E1F3C X-CRM114-Status: GOOD ( 15.43 ) X-Spam-Score: 0.2 (/) Cc: Russell King , Heiko Stuebner , Arnd Bergmann , linux-doc@vger.kernel.org, Catalin Marinas , Randy Dunlap , Will Deacon , linux-kernel@vger.kernel.org, Jonas Jensen , Wim Van Sebroeck , Maxime Ripard , Guenter Roeck X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Some hardware implements reboot through its watchdog hardware, for example by triggering a watchdog timeout. Platform specific code starts to spread into watchdog drivers, typically by setting pointers to a callback functions which is then called from the platform reset handler. To simplify code and provide a unified API to trigger reboots by watchdog drivers, provide a single API to trigger such reboots through the watchdog subsystem. Acked-by: Maxime Ripard Acked-by: Arnd Bergmann Tested-by: Jonas Jensen Acked-by: Heiko Stuebner Signed-off-by: Guenter Roeck --- v3: Drop reboot mode and cmd string parameters from API v2: Remove unnecessary check for ops in reboot function drivers/watchdog/watchdog_core.c | 15 +++++++++++++++ include/linux/watchdog.h | 8 ++++++++ 2 files changed, 23 insertions(+) diff --git a/drivers/watchdog/watchdog_core.c b/drivers/watchdog/watchdog_core.c index cec9b55..24ce780 100644 --- a/drivers/watchdog/watchdog_core.c +++ b/drivers/watchdog/watchdog_core.c @@ -43,6 +43,15 @@ static DEFINE_IDA(watchdog_ida); static struct class *watchdog_class; +static struct watchdog_device *wdd_reboot_dev; + +void watchdog_do_reboot(void) +{ + if (wdd_reboot_dev) + wdd_reboot_dev->ops->reboot(wdd_reboot_dev); +} +EXPORT_SYMBOL(watchdog_do_reboot); + static void watchdog_check_min_max_timeout(struct watchdog_device *wdd) { /* @@ -162,6 +171,9 @@ int watchdog_register_device(struct watchdog_device *wdd) return ret; } + if (wdd->ops->reboot) + wdd_reboot_dev = wdd; + return 0; } EXPORT_SYMBOL_GPL(watchdog_register_device); @@ -181,6 +193,9 @@ void watchdog_unregister_device(struct watchdog_device *wdd) if (wdd == NULL) return; + if (wdd == wdd_reboot_dev) + wdd_reboot_dev = NULL; + devno = wdd->cdev.dev; ret = watchdog_dev_unregister(wdd); if (ret) diff --git a/include/linux/watchdog.h b/include/linux/watchdog.h index 2a3038e..1e9da0a 100644 --- a/include/linux/watchdog.h +++ b/include/linux/watchdog.h @@ -23,6 +23,7 @@ struct watchdog_device; * @start: The routine for starting the watchdog device. * @stop: The routine for stopping the watchdog device. * @ping: The routine that sends a keepalive ping to the watchdog device. + * @reboot: The routine for rebooting the system * @status: The routine that shows the status of the watchdog device. * @set_timeout:The routine for setting the watchdog devices timeout value. * @get_timeleft:The routine that get's the time that's left before a reset. @@ -42,6 +43,7 @@ struct watchdog_ops { int (*stop)(struct watchdog_device *); /* optional operations */ int (*ping)(struct watchdog_device *); + void (*reboot)(struct watchdog_device *); unsigned int (*status)(struct watchdog_device *); int (*set_timeout)(struct watchdog_device *, unsigned int); unsigned int (*get_timeleft)(struct watchdog_device *); @@ -142,4 +144,10 @@ extern int watchdog_init_timeout(struct watchdog_device *wdd, extern int watchdog_register_device(struct watchdog_device *); extern void watchdog_unregister_device(struct watchdog_device *); +#ifdef CONFIG_WATCHDOG_CORE +extern void watchdog_do_reboot(void); +#else +static inline void watchdog_do_reboot(void) { } +#endif + #endif /* ifndef _LINUX_WATCHDOG_H */