diff options
| author | Jisheng Zhang | 2014-09-23 15:42:12 +0800 |
|---|---|---|
| committer | Wim Van Sebroeck | 2014-10-20 21:03:06 +0200 |
| commit | 31228f43ab528628c9b5f1351604361aa1d78533 (patch) | |
| tree | b3e2a9be36edb5b2fb5d585377706b1056642590 /drivers | |
| parent | 69a160a0543fd569661048a8692c10afcdb1914b (diff) | |
watchdog: dw_wdt: add restart handler support
The kernel core now provides an API to trigger a system restart.
Register with it to support restarting the system via. watchdog.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/watchdog/dw_wdt.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c index 449c88523364..9e577a64ec9e 100644 --- a/drivers/watchdog/dw_wdt.c +++ b/drivers/watchdog/dw_wdt.c @@ -21,6 +21,7 @@ #include <linux/bitops.h> #include <linux/clk.h> +#include <linux/delay.h> #include <linux/device.h> #include <linux/err.h> #include <linux/fs.h> @@ -29,9 +30,11 @@ #include <linux/miscdevice.h> #include <linux/module.h> #include <linux/moduleparam.h> +#include <linux/notifier.h> #include <linux/of.h> #include <linux/pm.h> #include <linux/platform_device.h> +#include <linux/reboot.h> #include <linux/spinlock.h> #include <linux/timer.h> #include <linux/uaccess.h> @@ -63,6 +66,7 @@ static struct { unsigned long next_heartbeat; struct timer_list timer; int expect_close; + struct notifier_block restart_handler; } dw_wdt; static inline int dw_wdt_is_enabled(void) @@ -121,6 +125,26 @@ static void dw_wdt_keepalive(void) WDOG_COUNTER_RESTART_REG_OFFSET); } +static int dw_wdt_restart_handle(struct notifier_block *this, + unsigned long mode, void *cmd) +{ + u32 val; + + writel(0, dw_wdt.regs + WDOG_TIMEOUT_RANGE_REG_OFFSET); + val = readl(dw_wdt.regs + WDOG_CONTROL_REG_OFFSET); + if (val & WDOG_CONTROL_REG_WDT_EN_MASK) + writel(WDOG_COUNTER_RESTART_KICK_VALUE, dw_wdt.regs + + WDOG_COUNTER_RESTART_REG_OFFSET); + else + writel(WDOG_CONTROL_REG_WDT_EN_MASK, + dw_wdt.regs + WDOG_CONTROL_REG_OFFSET); + + /* wait for reset to assert... */ + mdelay(500); + + return NOTIFY_DONE; +} + static void dw_wdt_ping(unsigned long data) { if (time_before(jiffies, dw_wdt.next_heartbeat) || @@ -316,6 +340,12 @@ static int dw_wdt_drv_probe(struct platform_device *pdev) if (ret) goto out_disable_clk; + dw_wdt.restart_handler.notifier_call = dw_wdt_restart_handle; + dw_wdt.restart_handler.priority = 128; + ret = register_restart_handler(&dw_wdt.restart_handler); + if (ret) + pr_warn("cannot register restart handler\n"); + dw_wdt_set_next_heartbeat(); setup_timer(&dw_wdt.timer, dw_wdt_ping, 0); mod_timer(&dw_wdt.timer, jiffies + WDT_TIMEOUT); @@ -330,6 +360,8 @@ out_disable_clk: static int dw_wdt_drv_remove(struct platform_device *pdev) { + unregister_restart_handler(&dw_wdt.restart_handler); + misc_deregister(&dw_wdt_miscdev); clk_disable_unprepare(dw_wdt.clk); |