watchdog: imx2_wdt: Drop .remove callback

.remove callback implementation doesn' call clk_disable_unprepare() which
is buggy, actually, we can just use devm_watchdog_register_device() and
devm_add_action_or_reset() to handle all necessary operations for remove
action, then .remove callback can be dropped.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/1582512687-13312-1-git-send-email-Anson.Huang@nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

drivers/watchdog/imx2_wdt.c

@@ -244,6 +244,11 @@ static const struct regmap_config imx2_wdt_regmap_config = {
 	.max_register = 0x8,
 };
 
+static void imx2_wdt_action(void *data)
+{
+	clk_disable_unprepare(data);
+}
+
 static int __init imx2_wdt_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -292,6 +297,10 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+	ret = devm_add_action_or_reset(dev, imx2_wdt_action, wdev->clk);
+	if (ret)
+		return ret;
+
 	regmap_read(wdev->regmap, IMX2_WDT_WRSR, &val);
 	wdog->bootstatus = val & IMX2_WDT_WRSR_TOUT ? WDIOF_CARDRESET : 0;
 
@@ -315,32 +324,7 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
 	 */
 	regmap_write(wdev->regmap, IMX2_WDT_WMCR, 0);
 
-	ret = watchdog_register_device(wdog);
-	if (ret)
-		goto disable_clk;
-
-	dev_info(dev, "timeout %d sec (nowayout=%d)\n",
-		 wdog->timeout, nowayout);
-
-	return 0;
-
-disable_clk:
-	clk_disable_unprepare(wdev->clk);
-	return ret;
-}
-
-static int __exit imx2_wdt_remove(struct platform_device *pdev)
-{
-	struct watchdog_device *wdog = platform_get_drvdata(pdev);
-	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
-
-	watchdog_unregister_device(wdog);
-
-	if (imx2_wdt_is_running(wdev)) {
-		imx2_wdt_ping(wdog);
-		dev_crit(&pdev->dev, "Device removed: Expect reboot!\n");
-	}
-	return 0;
+	return devm_watchdog_register_device(dev, wdog);
 }
 
 static void imx2_wdt_shutdown(struct platform_device *pdev)
@@ -417,7 +401,6 @@ static const struct of_device_id imx2_wdt_dt_ids[] = {
 MODULE_DEVICE_TABLE(of, imx2_wdt_dt_ids);
 
 static struct platform_driver imx2_wdt_driver = {
-	.remove		= __exit_p(imx2_wdt_remove),
 	.shutdown	= imx2_wdt_shutdown,
 	.driver		= {
 		.name	= DRIVER_NAME,