[PATCH v3] media: platform: mtk-mdp3: Fix return value check in mdp_probe()

[PATCH v3] media: platform: mtk-mdp3: Fix return value check in mdp_probe()

[Qiheng Lin]

In case of error, the function mtk_mutex_get()
returns ERR_PTR() and never returns NULL. The NULL test in the
return value check should be replaced with IS_ERR().
And also fix the err_free_mutex case.

Fixes: 61890ccaefaf ("media: platform: mtk-mdp3: add MediaTek MDP3 driver")
Signed-off-by: Qiheng Lin <linqiheng@huawei.com>
---

v3:
 - rebase on top of media_stage tree.
v2:
 - Add fix the err_return case.

 drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c b/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c
index 2d1f6ae9f080..97edcd9d1c81 100644
--- a/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c
+++ b/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c
@@ -207,8 +207,8 @@ static int mdp_probe(struct platform_device *pdev)
 	}
 	for (i = 0; i < MDP_PIPE_MAX; i++) {
 		mdp->mdp_mutex[i] = mtk_mutex_get(&mm_pdev->dev);
-		if (!mdp->mdp_mutex[i]) {
-			ret = -ENODEV;
+		if (IS_ERR(mdp->mdp_mutex[i])) {
+			ret = PTR_ERR(mdp->mdp_mutex[i]);
 			goto err_free_mutex;
 		}
 	}
@@ -289,7 +289,8 @@ static int mdp_probe(struct platform_device *pdev)
 	mdp_comp_destroy(mdp);
 err_free_mutex:
 	for (i = 0; i < MDP_PIPE_MAX; i++)
-		mtk_mutex_put(mdp->mdp_mutex[i]);
+		if (!IS_ERR_OR_NULL(mdp->mdp_mutex[i]))
+			mtk_mutex_put(mdp->mdp_mutex[i]);
 err_destroy_device:
 	kfree(mdp);
 err_return:
-- 
2.32.0

Re: [PATCH v3] media: platform: mtk-mdp3: Fix return value check in mdp_probe()

[AngeloGioacchino Del Regno]

Il 02/12/22 11:18, Qiheng Lin ha scritto:
> In case of error, the function mtk_mutex_get()
> returns ERR_PTR() and never returns NULL. The NULL test in the
> return value check should be replaced with IS_ERR().
> And also fix the err_free_mutex case.
> 
> Fixes: 61890ccaefaf ("media: platform: mtk-mdp3: add MediaTek MDP3 driver")
> Signed-off-by: Qiheng Lin <linqiheng@huawei.com>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>