On Wed, 2022-05-18 at 11:39 +0800, CK Hu wrote: > Hi, Xinlei: > > On Thu, 2022-05-12 at 14:30 +0800, xinlei.lee@xxxxxxxxxxxx wrote: > > From: Jitao Shi <jitao.shi@xxxxxxxxxxxx> > > > > In order to match the changes of "Use the drm_panel_bridge API", > > the poweron/poweroff of dsi is extracted from enable/disable and > > defined as new funcs (atomic_pre_enable/atomic_post_disable). > > > > Fixes: 2dd8075d2185 ("drm/mediatek: mtk_dsi: Use the > > drm_panel_bridge > > API") > > > > Signed-off-by: Jitao Shi <jitao.shi@xxxxxxxxxxxx> > > Signed-off-by: Xinlei Lee <xinlei.lee@xxxxxxxxxxxx> > > Reviewed-by: AngeloGioacchino Del Regno < > > angelogioacchino.delregno@xxxxxxxxxxxxx> > > Reviewed-by: Rex-BC Chen <rex-bc.chen@xxxxxxxxxxxx> > > --- > > drivers/gpu/drm/mediatek/mtk_dsi.c | 53 +++++++++++++++++++------- > > -- > > -- > > 1 file changed, 34 insertions(+), 19 deletions(-) > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c > > b/drivers/gpu/drm/mediatek/mtk_dsi.c > > index f880136cec09..d9a6b928dba8 100644 > > --- a/drivers/gpu/drm/mediatek/mtk_dsi.c > > +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c > > @@ -691,16 +691,6 @@ static void mtk_dsi_poweroff(struct mtk_dsi > > *dsi) > > if (--dsi->refcount != 0) > > return; > > > > - /* > > - * mtk_dsi_stop() and mtk_dsi_start() is asymmetric, since > > - * mtk_dsi_stop() should be called after > > mtk_drm_crtc_atomic_disable(), > > - * which needs irq for vblank, and mtk_dsi_stop() will disable > > irq. > > - * mtk_dsi_start() needs to be called in > > mtk_output_dsi_enable(), > > - * after dsi is fully set. > > - */ > > - mtk_dsi_stop(dsi); > > - > > - mtk_dsi_switch_to_cmd_mode(dsi, VM_DONE_INT_FLAG, 500); > > mtk_dsi_reset_engine(dsi); > > mtk_dsi_lane0_ulp_mode_enter(dsi); > > mtk_dsi_clk_ulp_mode_enter(dsi); > > @@ -715,17 +705,9 @@ static void mtk_dsi_poweroff(struct mtk_dsi > > *dsi) > > > > static void mtk_output_dsi_enable(struct mtk_dsi *dsi) > > { > > - int ret; > > - > > if (dsi->enabled) > > return; > > > > - ret = mtk_dsi_poweron(dsi); > > - if (ret < 0) { > > - DRM_ERROR("failed to power on dsi\n"); > > - return; > > - } > > - > > mtk_dsi_set_mode(dsi); > > mtk_dsi_clk_hs_mode(dsi, 1); > > > > @@ -739,7 +721,16 @@ static void mtk_output_dsi_disable(struct > > mtk_dsi *dsi) > > if (!dsi->enabled) > > return; > > > > - mtk_dsi_poweroff(dsi); > > + /* > > + * mtk_dsi_stop() and mtk_dsi_start() is asymmetric, since > > + * mtk_dsi_stop() should be called after > > mtk_drm_crtc_atomic_disable(), > > + * which needs irq for vblank, and mtk_dsi_stop() will disable > > irq. > > + * mtk_dsi_start() needs to be called in > > mtk_output_dsi_enable(), > > + * after dsi is fully set. > > + */ > > + mtk_dsi_stop(dsi); > > + > > + mtk_dsi_switch_to_cmd_mode(dsi, VM_DONE_INT_FLAG, 500); > > > > dsi->enabled = false; > > } > > @@ -776,13 +767,37 @@ static void > > mtk_dsi_bridge_atomic_enable(struct > > drm_bridge *bridge, > > { > > struct mtk_dsi *dsi = bridge_to_dsi(bridge); > > > > + if (dsi->refcount == 0) > > + return; > > This seems not related to pre_enable()/post_disable(). So separate > this > to another patch. > > Regards, > CK > > > + > > mtk_output_dsi_enable(dsi); > > } > > > > +static void mtk_dsi_bridge_atomic_pre_enable(struct drm_bridge > > *bridge, > > + struct drm_bridge_state > > *old_bridge_state) > > +{ > > + struct mtk_dsi *dsi = bridge_to_dsi(bridge); > > + int ret; > > + > > + ret = mtk_dsi_poweron(dsi); > > + if (ret < 0) > > + DRM_ERROR("failed to power on dsi\n"); > > +} > > + > > +static void mtk_dsi_bridge_atomic_post_disable(struct drm_bridge > > *bridge, > > + struct drm_bridge_state > > *old_bridge_state) > > +{ > > + struct mtk_dsi *dsi = bridge_to_dsi(bridge); > > + > > + mtk_dsi_poweroff(dsi); > > +} > > + > > static const struct drm_bridge_funcs mtk_dsi_bridge_funcs = { > > .attach = mtk_dsi_bridge_attach, > > .atomic_disable = mtk_dsi_bridge_atomic_disable, > > .atomic_enable = mtk_dsi_bridge_atomic_enable, > > + .atomic_pre_enable = mtk_dsi_bridge_atomic_pre_enable, > > + .atomic_post_disable = mtk_dsi_bridge_atomic_post_disable, > > .mode_set = mtk_dsi_bridge_mode_set, > > }; > > > > Hi CK: Thanks for your review. The modification here is related to pre_enable()/post_disable(). Because in the previous dsi_enable function, dsi_poweron will be executed first and then the dsi register will be operated. But the current modification will move dsi_poweron to the pre_enable function, and the pre_enable is of void type, when dsi_poweron fails, an error log will be printed, but the dsi register will be operated in dsi_enable later , it may cause bus hang. Therefore, dsi_poweron is judged in the dsi_enable function to avoid the above situation. I'll add that description in the comments on the next edition. Best Regards! xinlei