[v7,2/3] clk: clk-max77686: Clean clkdev lookup leak and use devm

Commit Message

Vaittinen, Matti Dec. 7, 2018, 11:10 a.m. UTC

clk-max77686 never clean clkdev lookup at remove. This can cause
oops if clk-max77686 is removed and inserted again. Fix leak by
using new devm clkdev lookup registration. Simplify also error
path by using new devm_of_clk_add_hw_provider.

Signed-off-by: Matti Vaittinen <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
---
Please note that the patch #2 requires this change to work correctly:
https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git/commit/?h=clk-next&id=05502bf9eb7a7297f5fa6f1d17b169b3d5b53570

 drivers/clk/clk-max77686.c | 28 ++++++----------------------
 1 file changed, 6 insertions(+), 22 deletions(-)

Comments

Stephen Boyd Feb. 6, 2019, 7:05 p.m. UTC | #1

Quoting Matti Vaittinen (2018-12-07 03:10:15)
> clk-max77686 never clean clkdev lookup at remove. This can cause
> oops if clk-max77686 is removed and inserted again. Fix leak by
> using new devm clkdev lookup registration. Simplify also error
> path by using new devm_of_clk_add_hw_provider.
> 
> Signed-off-by: Matti Vaittinen <[e-mail]>
> Reviewed-by: Krzysztof Kozlowski <[e-mail]>
> ---

Applied to clk-next

Patch

diff --git a/drivers/clk/clk-max77686.c b/drivers/clk/clk-max77686.c
index 22c937644c93..3727d5472450 100644
--- a/drivers/clk/clk-max77686.c
+++ b/drivers/clk/clk-max77686.c
@@ -235,8 +235,9 @@  static int max77686_clk_probe(struct platform_device *pdev)
 			return ret;
 		}
 
-		ret = clk_hw_register_clkdev(&max_clk_data->hw,
-					     max_clk_data->clk_idata.name, NULL);
+		ret = devm_clk_hw_register_clkdev(dev, &max_clk_data->hw,
+						  max_clk_data->clk_idata.name,
+						  NULL);
 		if (ret < 0) {
 			dev_err(dev, "Failed to clkdev register: %d\n", ret);
 			return ret;
@@ -244,8 +245,8 @@  static int max77686_clk_probe(struct platform_device *pdev)
 	}
 
 	if (parent->of_node) {
-		ret = of_clk_add_hw_provider(parent->of_node, of_clk_max77686_get,
-					     drv_data);
+		ret = devm_of_clk_add_hw_provider(dev, of_clk_max77686_get,
+						  drv_data);
 
 		if (ret < 0) {
 			dev_err(dev, "Failed to register OF clock provider: %d\n",
@@ -261,27 +262,11 @@  static int max77686_clk_probe(struct platform_device *pdev)
 					 1 << MAX77802_CLOCK_LOW_JITTER_SHIFT);
 		if (ret < 0) {
 			dev_err(dev, "Failed to config low-jitter: %d\n", ret);
-			goto remove_of_clk_provider;
+			return ret;
 		}
 	}
 
 	return 0;
-
-remove_of_clk_provider:
-	if (parent->of_node)
-		of_clk_del_provider(parent->of_node);
-
-	return ret;
-}
-
-static int max77686_clk_remove(struct platform_device *pdev)
-{
-	struct device *parent = pdev->dev.parent;
-
-	if (parent->of_node)
-		of_clk_del_provider(parent->of_node);
-
-	return 0;
 }
 
 static const struct platform_device_id max77686_clk_id[] = {
@@ -297,7 +282,6 @@  static struct platform_driver max77686_clk_driver = {
 		.name  = "max77686-clk",
 	},
 	.probe = max77686_clk_probe,
-	.remove = max77686_clk_remove,
 	.id_table = max77686_clk_id,
 };