drivers/rtc/rtc-tegra.c: use managed rtc_device_register()

Use devm_rtc_device_register() for registering RTC device.  This will
reduce the code for unregistering RTC device in cleanup path and remove
the implementation of remove callback of platform driver.
Signed-off-by: NLaxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: NThierry Reding <thierry.reding@avionic-design.de>
Reviewed-by: NStephen Warren <swarren@nvidia.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-tegra.c

@@ -349,13 +349,12 @@ static int __init tegra_rtc_probe(struct platform_device *pdev)
 
 	device_init_wakeup(&pdev->dev, 1);
 
-	info->rtc_dev = rtc_device_register(
-		pdev->name, &pdev->dev, &tegra_rtc_ops, THIS_MODULE);
+	info->rtc_dev = devm_rtc_device_register(&pdev->dev,
+				dev_name(&pdev->dev), &tegra_rtc_ops,
+				THIS_MODULE);
 	if (IS_ERR(info->rtc_dev)) {
 		ret = PTR_ERR(info->rtc_dev);
-		info->rtc_dev = NULL;
-		dev_err(&pdev->dev,
-			"Unable to register device (err=%d).\n",
+		dev_err(&pdev->dev, "Unable to register device (err=%d).\n",
 			ret);
 		return ret;
 	}
@@ -367,27 +366,11 @@ static int __init tegra_rtc_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev,
 			"Unable to request interrupt for device (err=%d).\n",
 			ret);
-		goto err_dev_unreg;
+		return ret;
 	}
 
 	dev_notice(&pdev->dev, "Tegra internal Real Time Clock\n");
 
-	return 0;
-
-err_dev_unreg:
-	rtc_device_unregister(info->rtc_dev);
-
-	return ret;
-}
-
-static int __exit tegra_rtc_remove(struct platform_device *pdev)
-{
-	struct tegra_rtc_info *info = platform_get_drvdata(pdev);
-
-	rtc_device_unregister(info->rtc_dev);
-
-	platform_set_drvdata(pdev, NULL);
-
 	return 0;
 }
 
@@ -440,7 +423,6 @@ static void tegra_rtc_shutdown(struct platform_device *pdev)
 
 MODULE_ALIAS("platform:tegra_rtc");
 static struct platform_driver tegra_rtc_driver = {
-	.remove		= __exit_p(tegra_rtc_remove),
 	.shutdown	= tegra_rtc_shutdown,
 	.driver		= {
 		.name	= "tegra_rtc",