Re: [PATCH] drm/mediatek: check for comp->funcs

Hi, Hsin-yi:

On Thu, 2020-01-09 at 15:29 +0800, Hsin-Yi Wang wrote:

There might be some comp that doesn't have funcs, eg. hdmi-connector. Check for comp->funcs otherwise there will be NULL pointer dereference crash.

Fixes: bd3de8cd782b ("drm/mediatek: Add gamma property according to hardware capability") Fixes: 7395eab077f9 ("drm/mediatek: Add ctm property support")

Because the fixed patches are still in my tree, so I merge this patch with the fixed patches in mediatek-drm-next-5.6 [1].

[1] https://github.com/ckhu-mediatek/linux.git-tags/commits/mediatek-drm-next-5....

Regards, CK

Signed-off-by: Hsin-Yi Wang hsinyi@chromium.org

This patch is based on mediatek's drm branch: https://github.com/ckhu-mediatek/linux.git-tags/commits/mediatek-drm-next-5....

After https://patchwork.freedesktop.org/patch/344477/?series=63328&rev=59, there will also be funcs for hdmi-connector.

---

drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c index fb142fcfc353..7b392d6c71cc 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c @@ -808,11 +808,13 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,

mtk_crtc->ddp_comp[i] = comp;

• if (comp->funcs->ctm_set)
  

• 	has_ctm = true;
  

• if (comp->funcs) {
  

• 	if (comp->funcs->ctm_set)
  

• 		has_ctm = true;
  
  

• if (comp->funcs->gamma_set)
  

• 	gamma_lut_size = MTK_LUT_SIZE;
  

• 	if (comp->funcs->gamma_set)
  

• 		gamma_lut_size = MTK_LUT_SIZE;
  

• }
  

  }

  for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)