diff options
Diffstat (limited to 'drivers/watchdog/imx2_wdt.c')
-rw-r--r-- | drivers/watchdog/imx2_wdt.c | 44 |
1 files changed, 33 insertions, 11 deletions
diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c index d6add516a7a..5e6d808d358 100644 --- a/drivers/watchdog/imx2_wdt.c +++ b/drivers/watchdog/imx2_wdt.c @@ -52,6 +52,8 @@ #define IMX2_WDT_WRSR 0x04 /* Reset Status Register */ #define IMX2_WDT_WRSR_TOUT (1 << 1) /* -> Reset due to Timeout */ +#define IMX2_WDT_WMCR 0x08 /* Misc Register */ + #define IMX2_WDT_MAX_TIME 128 #define IMX2_WDT_DEFAULT_TIME 60 /* in seconds */ @@ -203,7 +205,7 @@ static inline void imx2_wdt_ping_if_active(struct watchdog_device *wdog) } } -static struct watchdog_ops imx2_wdt_ops = { +static const struct watchdog_ops imx2_wdt_ops = { .owner = THIS_MODULE, .start = imx2_wdt_start, .stop = imx2_wdt_stop, @@ -211,7 +213,7 @@ static struct watchdog_ops imx2_wdt_ops = { .set_timeout = imx2_wdt_set_timeout, }; -static struct regmap_config imx2_wdt_regmap_config = { +static const struct regmap_config imx2_wdt_regmap_config = { .reg_bits = 16, .reg_stride = 2, .val_bits = 16, @@ -274,6 +276,13 @@ static int __init imx2_wdt_probe(struct platform_device *pdev) imx2_wdt_ping_if_active(wdog); + /* + * Disable the watchdog power down counter at boot. Otherwise the power + * down counter will pull down the #WDOG interrupt line for one clock + * cycle. + */ + regmap_write(wdev->regmap, IMX2_WDT_WMCR, 0); + ret = watchdog_register_device(wdog); if (ret) { dev_err(&pdev->dev, "cannot register watchdog device\n"); @@ -327,18 +336,21 @@ static void imx2_wdt_shutdown(struct platform_device *pdev) } #ifdef CONFIG_PM_SLEEP -/* Disable watchdog if it is active during suspend */ +/* Disable watchdog if it is active or non-active but still running */ static int imx2_wdt_suspend(struct device *dev) { struct watchdog_device *wdog = dev_get_drvdata(dev); struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); - imx2_wdt_set_timeout(wdog, IMX2_WDT_MAX_TIME); - imx2_wdt_ping(wdog); + /* The watchdog IP block is running */ + if (imx2_wdt_is_running(wdev)) { + imx2_wdt_set_timeout(wdog, IMX2_WDT_MAX_TIME); + imx2_wdt_ping(wdog); - /* Watchdog has been stopped but IP block is still running */ - if (!watchdog_active(wdog) && imx2_wdt_is_running(wdev)) - del_timer_sync(&wdev->timer); + /* The watchdog is not active */ + if (!watchdog_active(wdog)) + del_timer_sync(&wdev->timer); + } clk_disable_unprepare(wdev->clk); @@ -354,15 +366,25 @@ static int imx2_wdt_resume(struct device *dev) clk_prepare_enable(wdev->clk); if (watchdog_active(wdog) && !imx2_wdt_is_running(wdev)) { - /* Resumes from deep sleep we need restart - * the watchdog again. + /* + * If the watchdog is still active and resumes + * from deep sleep state, need to restart the + * watchdog again. */ imx2_wdt_setup(wdog); imx2_wdt_set_timeout(wdog, wdog->timeout); imx2_wdt_ping(wdog); } else if (imx2_wdt_is_running(wdev)) { + /* Resuming from non-deep sleep state. */ + imx2_wdt_set_timeout(wdog, wdog->timeout); imx2_wdt_ping(wdog); - mod_timer(&wdev->timer, jiffies + wdog->timeout * HZ / 2); + /* + * But the watchdog is not active, then start + * the timer again. + */ + if (!watchdog_active(wdog)) + mod_timer(&wdev->timer, + jiffies + wdog->timeout * HZ / 2); } return 0; |