From: Guenter Roeck Date: Sun, 24 Dec 2017 21:04:16 +0000 (-0800) Subject: watchdog: sp5100-tco: Abort if watchdog is disabled by hardware X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=f7781b067522aa269213e8025c80cbed1868d349;p=linux.git watchdog: sp5100-tco: Abort if watchdog is disabled by hardware If the watchdog control register indicates that the watchdog hardware is disabled even after we tried to enable it, there is no point to instantiate the driver. Cc: Zoltán Böszörményi Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- diff --git a/drivers/watchdog/sp5100_tco.c b/drivers/watchdog/sp5100_tco.c index bb6c4608c1c05..23246cb40598c 100644 --- a/drivers/watchdog/sp5100_tco.c +++ b/drivers/watchdog/sp5100_tco.c @@ -273,14 +273,20 @@ static int sp5100_tco_setupdevice(struct device *dev, /* Setup the watchdog timer */ tco_timer_enable(); - /* Check that the watchdog action is set to reset the system */ val = readl(SP5100_WDT_CONTROL(tco->tcobase)); + if (val & SP5100_WDT_DISABLED) { + dev_err(dev, "Watchdog hardware is disabled\n"); + ret = -ENODEV; + goto unreg_region; + } + /* * Save WatchDogFired status, because WatchDogFired flag is * cleared here. */ if (val & SP5100_WDT_FIRED) wdd->bootstatus = WDIOF_CARDRESET; + /* Set watchdog action to reset the system */ val &= ~SP5100_WDT_ACTION_RESET; writel(val, SP5100_WDT_CONTROL(tco->tcobase)); diff --git a/drivers/watchdog/sp5100_tco.h b/drivers/watchdog/sp5100_tco.h index ca0721c8d8793..008b2094bd13a 100644 --- a/drivers/watchdog/sp5100_tco.h +++ b/drivers/watchdog/sp5100_tco.h @@ -19,6 +19,7 @@ #define SP5100_WDT_START_STOP_BIT BIT(0) #define SP5100_WDT_FIRED BIT(1) #define SP5100_WDT_ACTION_RESET BIT(2) +#define SP5100_WDT_DISABLED BIT(3) #define SP5100_WDT_TRIGGER_BIT BIT(7) #define SP5100_PM_IOPORTS_SIZE 0x02