Re: [PATCH v4 3/4] drm/mediatek: Add gamma correction.

From: Philipp Zabel
Date: Thu Aug 11 2016 - 03:51:57 EST


Am Donnerstag, den 11.08.2016, 10:44 +0300 schrieb Ville SyrjÃlÃ:
> On Thu, Aug 11, 2016 at 09:32:59AM +0200, Philipp Zabel wrote:
> > Am Donnerstag, den 28.07.2016, 10:22 +0800 schrieb Bibby Hsieh:
> > > Add gamma set function to correct brightness values.
> > > It applies arbitrary mapping curve to compensate the
> > > incorrect transfer function of the panel.
> > >
> > > Signed-off-by: Bibby Hsieh <bibby.hsieh@xxxxxxxxxxxx>
> > > ---
> > > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 8 ++++++-
> > > drivers/gpu/drm/mediatek/mtk_drm_crtc.h | 1 +
> > > drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c | 31 +++++++++++++++++++++++++++
> > > drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h | 10 +++++++++
> > > 4 files changed, 49 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > index 24aa3ba..cbb460a5 100644
> > > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > > @@ -409,6 +409,9 @@ static void mtk_drm_crtc_atomic_flush(struct drm_crtc *crtc,
> > > }
> > > if (pending_planes)
> > > mtk_crtc->pending_planes = true;
> > > + if (crtc->state->color_mgmt_changed)
> > > + for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
> > > + mtk_ddp_gamma_set(mtk_crtc->ddp_comp[i], crtc->state);
> > > }
> > >
> > > static const struct drm_crtc_funcs mtk_crtc_funcs = {
> > > @@ -418,6 +421,7 @@ static const struct drm_crtc_funcs mtk_crtc_funcs = {
> > > .reset = mtk_drm_crtc_reset,
> > > .atomic_duplicate_state = mtk_drm_crtc_duplicate_state,
> > > .atomic_destroy_state = mtk_drm_crtc_destroy_state,
> > > + .gamma_set = drm_atomic_helper_legacy_gamma_set,
> > > };
> > >
> > > static const struct drm_crtc_helper_funcs mtk_crtc_helper_funcs = {
> > > @@ -568,7 +572,9 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
> > > &mtk_crtc->planes[1].base, pipe);
> > > if (ret < 0)
> > > goto unprepare;
> > > -
> > > + drm_mode_crtc_set_gamma_size(&mtk_crtc->base, MTK_LUT_SIZE);
> > > + drm_helper_crtc_enable_color_mgmt(&mtk_crtc->base, MTK_LUT_SIZE,
> > > + MTK_LUT_SIZE);
> >
> > I have applied all four patches and rebased onto v4.8-rc1, replacing
> > drm_helper_crtc_enable_color_mgmt with:
> >
> > drm_crtc_enable_color_mgmt(&mtk_crtc->base, MTK_LUT_SIZE,
> > true, MTK_LUT_SIZE);
>
> BTW that looks wrong (already in the original). AFAICS the patch just
> handled the gamma_lut, not the degamma_lut, so telling you have both
> is not right.

Thanks, so should that be
drm_crtc_enable_color_mgmt(&mtk_crtc->base, 0, false,
MTK_LUT_SIZE);
instead, since we only handle gamma?

regards
Philipp