From f7781b067522aa269213e8025c80cbed1868d349 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Sun, 24 Dec 2017 13:04:16 -0800 Subject: [PATCH] watchdog: sp5100-tco: Abort if watchdog is disabled by hardware MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 --- drivers/watchdog/sp5100_tco.c | 8 +++++++- drivers/watchdog/sp5100_tco.h | 1 + 2 files changed, 8 insertions(+), 1 deletion(-) 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