diff options
| author | Rasmus Villemoes <rasmus.villemoes@prevas.dk> | 2016-12-12 12:48:43 +0300 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2016-12-16 17:53:55 +0300 |
| commit | 054ae19422859c394d5f26a8756ed57d332f6284 (patch) | |
| tree | e08a660bf94481c1bf8edbead873374a4de7763c /drivers/watchdog/bcm2835_wdt.c | |
| parent | 1d8565ee4f5bd9fccb738e53d6b9fc7a559f7d2b (diff) | |
| download | linux-054ae19422859c394d5f26a8756ed57d332f6284.tar.xz | |
watchdog: bcm2835_wdt: set WDOG_HW_RUNNING bit when appropriate
A bootloader may start the watchdog device before handing control to
the kernel - in that case, we should tell the kernel about it so the
watchdog framework can keep it alive until userspace opens
/dev/watchdog0.
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/watchdog/bcm2835_wdt.c')
| -rw-r--r-- | drivers/watchdog/bcm2835_wdt.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/drivers/watchdog/bcm2835_wdt.c b/drivers/watchdog/bcm2835_wdt.c index 4dddd8298a22..c32c45bd8b09 100644 --- a/drivers/watchdog/bcm2835_wdt.c +++ b/drivers/watchdog/bcm2835_wdt.c @@ -55,6 +55,15 @@ struct bcm2835_wdt { static unsigned int heartbeat; static bool nowayout = WATCHDOG_NOWAYOUT; +static bool bcm2835_wdt_is_running(struct bcm2835_wdt *wdt) +{ + uint32_t cur; + + cur = readl(wdt->base + PM_RSTC); + + return !!(cur & PM_RSTC_WRCFG_FULL_RESET); +} + static int bcm2835_wdt_start(struct watchdog_device *wdog) { struct bcm2835_wdt *wdt = watchdog_get_drvdata(wdog); @@ -181,6 +190,17 @@ static int bcm2835_wdt_probe(struct platform_device *pdev) watchdog_init_timeout(&bcm2835_wdt_wdd, heartbeat, dev); watchdog_set_nowayout(&bcm2835_wdt_wdd, nowayout); bcm2835_wdt_wdd.parent = &pdev->dev; + if (bcm2835_wdt_is_running(wdt)) { + /* + * The currently active timeout value (set by the + * bootloader) may be different from the module + * heartbeat parameter or the value in device + * tree. But we just need to set WDOG_HW_RUNNING, + * because then the framework will "immediately" ping + * the device, updating the timeout. + */ + set_bit(WDOG_HW_RUNNING, &bcm2835_wdt_wdd.status); + } err = watchdog_register_device(&bcm2835_wdt_wdd); if (err) { dev_err(dev, "Failed to register watchdog device"); |