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

CK Hu
2019-12-13T08:10:05Z

Hi, Yongqiang:

On Fri, 2019-12-13 at 16:03 +0800, Yongqiang Niu wrote:
> On Fri, 2019-12-13 at 15:48 +0800, CK Hu wrote:
> > 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
>
> drm_crtc_enable_color_mgmt will check the gamma_lut_size parameter,
> if no gamma, gamma_lut_size will be 0, and gamma_lut_size will not attch
> gamma property for the crtc

OK, you're right. So

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

and what title would you like?
I could modify it when I apply this patch.

Regards,
CK

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