[PATCH 42/62] watchdog: pic32-dmt: Convert to use device managed functions

[Guenter Roeck]

Use device managed functions to simplify error handling, reduce
source code size, improve readability, and reduce the likelyhood of bugs.

The conversion was done automatically with coccinelle using the
following semantic patches. The semantic patches and the scripts used
to generate this commit log are available at
https://github.com/groeck/coccinelle-patches

- Use devm_add_action_or_reset() for calls to clk_disable_unprepare
- Replace 'goto l; ... l: return e;' with 'return e;'
- Replace 'val = e; return val;' with 'return e;'
- Drop assignments to otherwise unused variables
- Drop remove function
- Drop platform_set_drvdata()
- Use devm_watchdog_register_driver() to register watchdog device

Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
 drivers/watchdog/pic32-dmt.c | 29 ++++++++---------------------
 1 file changed, 8 insertions(+), 21 deletions(-)

diff --git a/drivers/watchdog/pic32-dmt.c b/drivers/watchdog/pic32-dmt.c
index c797305f8338..31d635639049 100644
--- a/drivers/watchdog/pic32-dmt.c
+++ b/drivers/watchdog/pic32-dmt.c
@@ -193,13 +193,17 @@ static int pic32_dmt_probe(struct platform_device *pdev)
 	ret = clk_prepare_enable(dmt->clk);
 	if (ret)
 		return ret;
+	ret = devm_add_action_or_reset(&pdev->dev,
+				       (void(*)(void *))clk_disable_unprepare,
+				       dmt->clk);
+	if (ret)
+		return ret;
 
 	wdd->timeout = pic32_dmt_get_timeout_secs(dmt);
 	if (!wdd->timeout) {
 		dev_err(&pdev->dev,
 			"failed to read watchdog register timeout\n");
-		ret = -EINVAL;
-		goto out_disable_clk;
+		return -EINVAL;
 	}
 
 	dev_info(&pdev->dev, "timeout %d\n", wdd->timeout);
@@ -209,28 +213,12 @@ static int pic32_dmt_probe(struct platform_device *pdev)
 	watchdog_set_nowayout(wdd, WATCHDOG_NOWAYOUT);
 	watchdog_set_drvdata(wdd, dmt);
 
-	ret = watchdog_register_device(wdd);
+	ret = devm_watchdog_register_device(&pdev->dev, wdd);
 	if (ret) {
 		dev_err(&pdev->dev, "watchdog register failed, err %d\n", ret);
-		goto out_disable_clk;
+		return ret;
 	}
 
-	platform_set_drvdata(pdev, wdd);
-	return 0;
-
-out_disable_clk:
-	clk_disable_unprepare(dmt->clk);
-	return ret;
-}
-
-static int pic32_dmt_remove(struct platform_device *pdev)
-{
-	struct watchdog_device *wdd = platform_get_drvdata(pdev);
-	struct pic32_dmt *dmt = watchdog_get_drvdata(wdd);
-
-	watchdog_unregister_device(wdd);
-	clk_disable_unprepare(dmt->clk);
-
 	return 0;
 }
 
@@ -242,7 +230,6 @@ MODULE_DEVICE_TABLE(of, pic32_dmt_of_ids);
 
 static struct platform_driver pic32_dmt_driver = {
 	.probe		= pic32_dmt_probe,
-	.remove		= pic32_dmt_remove,
 	.driver		= {
 		.name		= "pic32-dmt",
 		.of_match_table = of_match_ptr(pic32_dmt_of_ids),
-- 
2.7.4