5.4-stable review patch. If anyone has any objections, please let me know.
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From: Jonas Blixt jonas.blixt@actia.se
[ Upstream commit 2d9d6d300fb0a4ae4431bb308027ac9385746d42 ]
Parts of the suspend and resume chain is left unprotected if we disable the WDT here.
From experiments we can see that the SCU disables and re-enables the WDT
when we enter and leave suspend to ram. By not touching the WDT here we are protected by the WDT all the way to the SCU.
Signed-off-by: Jonas Blixt jonas.blixt@actia.se CC: Anson Huang anson.huang@nxp.com Fixes: 986857acbc9a ("watchdog: imx_sc: Add i.MX system controller watchdog support") Reviewed-by: Guenter Roeck linux@roeck-us.net Link: https://lore.kernel.org/r/20240801121845.1465765-1-jonas.blixt@actia.se Signed-off-by: Guenter Roeck linux@roeck-us.net Signed-off-by: Wim Van Sebroeck wim@linux-watchdog.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/watchdog/imx_sc_wdt.c | 24 ------------------------ 1 file changed, 24 deletions(-)
diff --git a/drivers/watchdog/imx_sc_wdt.c b/drivers/watchdog/imx_sc_wdt.c index 8c9936e78bee0..f11f4c2bb0e50 100644 --- a/drivers/watchdog/imx_sc_wdt.c +++ b/drivers/watchdog/imx_sc_wdt.c @@ -215,29 +215,6 @@ static int imx_sc_wdt_probe(struct platform_device *pdev) return devm_watchdog_register_device(dev, wdog); }
-static int __maybe_unused imx_sc_wdt_suspend(struct device *dev) -{ - struct imx_sc_wdt_device *imx_sc_wdd = dev_get_drvdata(dev); - - if (watchdog_active(&imx_sc_wdd->wdd)) - imx_sc_wdt_stop(&imx_sc_wdd->wdd); - - return 0; -} - -static int __maybe_unused imx_sc_wdt_resume(struct device *dev) -{ - struct imx_sc_wdt_device *imx_sc_wdd = dev_get_drvdata(dev); - - if (watchdog_active(&imx_sc_wdd->wdd)) - imx_sc_wdt_start(&imx_sc_wdd->wdd); - - return 0; -} - -static SIMPLE_DEV_PM_OPS(imx_sc_wdt_pm_ops, - imx_sc_wdt_suspend, imx_sc_wdt_resume); - static const struct of_device_id imx_sc_wdt_dt_ids[] = { { .compatible = "fsl,imx-sc-wdt", }, { /* sentinel */ } @@ -249,7 +226,6 @@ static struct platform_driver imx_sc_wdt_driver = { .driver = { .name = "imx-sc-wdt", .of_match_table = imx_sc_wdt_dt_ids, - .pm = &imx_sc_wdt_pm_ops, }, }; module_platform_driver(imx_sc_wdt_driver);