From aefbaf3a3fa030ed7ef3cc9456ed82e6611c1dcb Mon Sep 17 00:00:00 2001 From: Xiubo Li Date: Mon, 22 Sep 2014 18:00:52 +0800 Subject: watchdog: imx2_wdt: Add power management support. Add power management operations(suspend and resume) as part of dev_pm_ops for IMX2 watchdog driver. Signed-off-by: Xiubo Li Reviewed-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/imx2_wdt.c | 47 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) (limited to 'drivers') diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c index 65b84d8c0b9..51d940beb31 100644 --- a/drivers/watchdog/imx2_wdt.c +++ b/drivers/watchdog/imx2_wdt.c @@ -326,6 +326,52 @@ static void imx2_wdt_shutdown(struct platform_device *pdev) } } +#ifdef CONFIG_PM_SLEEP +/* Disable watchdog if it is active during suspend */ +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); + + /* Watchdog has been stopped but IP block is still running */ + if (!watchdog_active(&wdog) && imx2_wdt_is_running(wdev)) + del_timer_sync(&wdev->timer); + + clk_disable_unprepare(wdev->clk); + + return 0; +} + +/* Enable watchdog and configure it if necessary */ +static int imx2_wdt_resume(struct device *dev) +{ + struct watchdog_device *wdog = dev_get_drvdata(dev); + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); + + clk_prepare_enable(wdev->clk); + + if (watchdog_active(wdog) && !imx2_wdt_is_running(wdev)) { + /* Resumes from deep sleep we need 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)) { + imx2_wdt_ping(wdog); + mod_timer(&wdev->timer, jiffies + wdog->timeout * HZ / 2); + } + + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(imx2_wdt_pm_ops, imx2_wdt_suspend, + imx2_wdt_resume); + static const struct of_device_id imx2_wdt_dt_ids[] = { { .compatible = "fsl,imx21-wdt", }, { /* sentinel */ } @@ -337,6 +383,7 @@ static struct platform_driver imx2_wdt_driver = { .shutdown = imx2_wdt_shutdown, .driver = { .name = DRIVER_NAME, + .pm = &imx2_wdt_pm_ops, .of_match_table = imx2_wdt_dt_ids, }, }; -- cgit v1.2.3-70-g09d2