Re: [PATCH v2, 1/2] drm/mediatek: Fix gamma correction issue

CK Hu
2019-12-13T07:56:37Z

Hi, Yongqiang:

The title is too rough. Any bug of gamma would be this title. I would
like the title show explicitly what it does.

On Fri, 2019-12-13 at 15:28 +0800, Yongqiang Niu wrote:
> if there is no gamma function in the crtc
> display path, don't add gamma property
> for crtc
>
> Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index ca4fc47..9a8e1d4 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -734,6 +734,7 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
> int pipe = priv->num_pipes;
> int ret;
> int i;
> + uint gamma_lut_size = 0;
>
> if (!path)
> return 0;
> @@ -785,6 +786,9 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
> }
>
> mtk_crtc->ddp_comp[i] = comp;
> +
> + if (comp->funcs->gamma_set)
> + gamma_lut_size = MTK_LUT_SIZE;
> }
>
> for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
> @@ -805,8 +809,10 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
> NULL, pipe);
> if (ret < 0)
> return ret;
> - drm_mode_crtc_set_gamma_size(&mtk_crtc->base, MTK_LUT_SIZE);
> - drm_crtc_enable_color_mgmt(&mtk_crtc->base, 0, false, MTK_LUT_SIZE);
> +
> + if (gamma_lut_size)
> + drm_mode_crtc_set_gamma_size(&mtk_crtc->base, gamma_lut_size);
> + drm_crtc_enable_color_mgmt(&mtk_crtc->base, 0, false, gamma_lut_size);

If there is no gamma, shall we enable color management?

Regards,
CK

> priv->num_pipes++;
> mutex_init(&mtk_crtc->hw_lock);