Re: [PATCH] drm/mediatek: Check return value of mtk_drm_ddp_comp_for_plane.

From: CK Hu
Date: Fri Nov 22 2019 - 02:58:54 EST


Hi, Pi-Hsun:

On Mon, 2019-11-18 at 14:18 +0800, Pi-Hsun Shih wrote:
> The mtk_drm_ddp_comp_for_plane can return NULL, but the usage doesn't
> check for it. Add check for it.

Reviewed-by: CK Hu <ck.hu@xxxxxxxxxxxx>

>
> Fixes: d6b53f68356f ("drm/mediatek: Add helper to get component for a plane")
> Signed-off-by: Pi-Hsun Shih <pihsun@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 13 +++++++++----
> 1 file changed, 9 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index f80a8ba75977..4c4f976c994e 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -310,7 +310,9 @@ static int mtk_crtc_ddp_hw_init(struct mtk_drm_crtc *mtk_crtc)
>
> plane_state = to_mtk_plane_state(plane->state);
> comp = mtk_drm_ddp_comp_for_plane(crtc, plane, &local_layer);
> - mtk_ddp_comp_layer_config(comp, local_layer, plane_state);
> + if (comp)
> + mtk_ddp_comp_layer_config(comp, local_layer,
> + plane_state);
> }
>
> return 0;
> @@ -386,8 +388,9 @@ static void mtk_crtc_ddp_config(struct drm_crtc *crtc)
> comp = mtk_drm_ddp_comp_for_plane(crtc, plane,
> &local_layer);
>
> - mtk_ddp_comp_layer_config(comp, local_layer,
> - plane_state);
> + if (comp)
> + mtk_ddp_comp_layer_config(comp, local_layer,
> + plane_state);
> plane_state->pending.config = false;
> }
> mtk_crtc->pending_planes = false;
> @@ -401,7 +404,9 @@ int mtk_drm_crtc_plane_check(struct drm_crtc *crtc, struct drm_plane *plane,
> struct mtk_ddp_comp *comp;
>
> comp = mtk_drm_ddp_comp_for_plane(crtc, plane, &local_layer);
> - return mtk_ddp_comp_layer_check(comp, local_layer, state);
> + if (comp)
> + return mtk_ddp_comp_layer_check(comp, local_layer, state);
> + return 0;
> }
>
> static void mtk_drm_crtc_atomic_enable(struct drm_crtc *crtc,
>
> base-commit: 5a6fcbeabe3e20459ed8504690b2515dacc5246f