Hi, Yongqiang: I would like the title could clearly express what does this patch do. I think what this patch do is to implement prepare/unprepare interface for dpi driver. And you could describe why do this in commit message. On Wed, 2019-11-27 at 09:17 +0800, yongqiang.niu@xxxxxxxxxxxx wrote: > From: Yongqiang Niu <yongqiang.niu@xxxxxxxxxxxx> > > Fix external display vblank timeout issue I think you move dpi_power_on to more early stage. But why this would fix vblank timeout. Please describe more about this so that I would agree this patch. This is a bug fix, so please add a 'Fixes' tag. > > Signed-off-by: Yongqiang Niu <yongqiang.niu@xxxxxxxxxxxx> > --- > drivers/gpu/drm/mediatek/mtk_dpi.c | 14 +++++++++----- > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 6 ++++++ > drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h | 14 ++++++++++++++ > 3 files changed, 29 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c > index be6d95c..38cabbe 100644 > --- a/drivers/gpu/drm/mediatek/mtk_dpi.c > +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c > @@ -387,8 +387,12 @@ static int mtk_dpi_power_on(struct mtk_dpi *dpi) > { > int ret; > > - if (++dpi->refcount != 1) > + if (++dpi->refcount != 1) { > + dev_warn(dpi->dev, "%s refcount: %d\n", __func__, dpi->refcount); > return 0; > + } > + > + DRM_DEBUG_DRIVER("%s refcount %d\n", __func__, dpi->refcount); > > ret = clk_prepare_enable(dpi->engine_clk); > if (ret) { > @@ -563,14 +567,14 @@ static int mtk_dpi_atomic_check(struct drm_encoder *encoder, > .atomic_check = mtk_dpi_atomic_check, > }; > > -static void mtk_dpi_start(struct mtk_ddp_comp *comp) > +static void mtk_dpi_prepare(struct mtk_ddp_comp *comp) > { > struct mtk_dpi *dpi = container_of(comp, struct mtk_dpi, ddp_comp); > > mtk_dpi_power_on(dpi); > } > > -static void mtk_dpi_stop(struct mtk_ddp_comp *comp) > +static void mtk_dpi_unprepare(struct mtk_ddp_comp *comp) > { > struct mtk_dpi *dpi = container_of(comp, struct mtk_dpi, ddp_comp); > > @@ -578,8 +582,8 @@ static void mtk_dpi_stop(struct mtk_ddp_comp *comp) > } > > static const struct mtk_ddp_comp_funcs mtk_dpi_funcs = { > - .start = mtk_dpi_start, > - .stop = mtk_dpi_stop, > + .prepare = mtk_dpi_prepare, > + .unprepare = mtk_dpi_unprepare, > }; > > static int mtk_dpi_bind(struct device *dev, struct device *master, void *data) > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c > index 7eca02f..a6d3d97 100644 > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c > @@ -345,6 +345,9 @@ static int mtk_crtc_ddp_hw_init(struct mtk_drm_crtc *mtk_crtc) > return ret; > } > > + for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) > + mtk_ddp_comp_prepare(mtk_crtc->ddp_comp[i]); > + > ret = mtk_disp_mutex_prepare(mtk_crtc->mutex); > if (ret < 0) { > DRM_ERROR("Failed to enable mutex clock: %d\n", ret); > @@ -434,6 +437,9 @@ static void mtk_crtc_ddp_hw_fini(struct mtk_drm_crtc *mtk_crtc) > mtk_crtc_ddp_clk_disable(mtk_crtc); > mtk_disp_mutex_unprepare(mtk_crtc->mutex); > > + for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) > + mtk_ddp_comp_unprepare(mtk_crtc->ddp_comp[i]); > + > pm_runtime_put(drm->dev); > > if (crtc->state->event && !crtc->state->active) { > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h > index 5b0a3d4..097b90d 100644 > --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h > +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h > @@ -78,6 +78,8 @@ struct mtk_ddp_comp_funcs { > void (*stop)(struct mtk_ddp_comp *comp); > void (*enable_vblank)(struct mtk_ddp_comp *comp, struct drm_crtc *crtc); > void (*disable_vblank)(struct mtk_ddp_comp *comp); > + void (*prepare)(struct mtk_ddp_comp *comp); > + void (*unprepare)(struct mtk_ddp_comp *comp); > unsigned int (*supported_rotations)(struct mtk_ddp_comp *comp); > unsigned int (*layer_nr)(struct mtk_ddp_comp *comp); > void (*layer_on)(struct mtk_ddp_comp *comp, unsigned int idx, > @@ -117,6 +119,18 @@ static inline void mtk_ddp_comp_config(struct mtk_ddp_comp *comp, > comp->funcs->config(comp, w, h, vrefresh, bpc, cmdq_pkt); > } > > +static inline void mtk_ddp_comp_prepare(struct mtk_ddp_comp *comp) > +{ > + if (comp->funcs && comp->funcs->prepare) > + comp->funcs->prepare(comp); > +} > + > +static inline void mtk_ddp_comp_unprepare(struct mtk_ddp_comp *comp) > +{ > + if (comp->funcs && comp->funcs->unprepare) > + comp->funcs->unprepare(comp); > +} > + > static inline void mtk_ddp_comp_start(struct mtk_ddp_comp *comp) > { > if (comp->funcs && comp->funcs->start)