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

From: Qiheng Lin
Date: Wed Nov 30 2022 - 21:09:29 EST


在 2022/11/30 17:44, AngeloGioacchino Del Regno 写道:
Il 30/11/22 09:13, 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().

Fixes: 61890ccaefaf ("media: platform: mtk-mdp3: add MediaTek MDP3 driver")
Signed-off-by: Qiheng Lin <linqiheng@xxxxxxxxxx>
---
  drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c | 4 ++--
  1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c b/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c
index c413e59d4286..7a2d992dd842 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_return;
          }
      }


That's true, and I fully agree.
While you're at it, can you also fix the err_return case?

if (mdp)
    for ...
        if (!IS_ERR_OR_NULL(mdp->mdp_mutex[i]))
            mtk_mutex_put(...)


Thanks for your suggestion, will send the v2.

Thanks,
Angelo