On Mon, Dec 02, 2024 at 04:38:59PM -0800, Abhinav Kumar wrote: > HPD state machine in msm dp display driver manages the state transitions > between various HPD events and the expected state of driver to make sure > both match up. > > Although originally done with the intent of managing userspace interactions > and interactions with compliance equipment, over period of time, > changes to this piece of code has become quite difficult to manage. > > Although, unwinding this logic will take some time and will be spread over > various changes, to start things, this series tries to get rid of the > ST_DISPLAY_OFF state as firstly, its really not an hpd state but a state > of the display overall. Coupled with this, there are quite a few checks > in the current code, the origins of which need to be re-visited OR are unclear > which seem unlikely or redundant. With DP controller on newer chipsets supporting > multiple streams, this has become increasingly difficult to work with. > > This series removes the redundant state checks and simplifies the logic as an > attempt to get rid of this ST_DISPLAY_OFF state. > > Note: This series has been tested with sa8775p and sc7180 devices with multiple > monitors and also multiple dongles with no noticeable regressions. > Both of these devices use native DP PHY though. Hence, if this series can > be verified on some devices with USBC-DP combo PHY with the help of the other > developers, that will be great. Don't you also have an RB5 (for pmic-typec) and SM83(?)50-HDK for pmic-glink? What kind of userspace were you testing with? Have you tested pure fbcon / drm_client? > > To: Rob Clark <robdclark@xxxxxxxxx> > To: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> > To: Sean Paul <sean@xxxxxxxxxx> > To: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx> > To: David Airlie <airlied@xxxxxxxxx> > To: Simona Vetter <simona@xxxxxxxx> > Cc: linux-arm-msm@xxxxxxxxxxxxxxx > Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx > Cc: freedreno@xxxxxxxxxxxxxxxxxxxxx > Cc: Stephen Boyd <swboyd@xxxxxxxxxxxx> > Cc: Doug Anderson <dianders@xxxxxxxxxxxx> > Cc: Johan Hovold <johan@xxxxxxxxxx> > Cc: Bjorn Andersson <quic_bjorande@xxxxxxxxxxx> > > Signed-off-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx> > --- > Abhinav Kumar (4): > drm/msm/dp: remove redundant checks related to ST_DISPLAY_OFF in plug/irq_ipd handlers > drm/msm/dp: remove redundant ST_DISPLAY_OFF checks in msm_dp_bridge_atomic_enable() > drm/msm/dp: replace ST_DISPLAY_OFF with power_on in msm_dp_hpd_unplug_handle() > drm/msm/dp: remove ST_DISPLAY_OFF as a hpd_state > > drivers/gpu/drm/msm/dp/dp_display.c | 23 ++--------------------- > 1 file changed, 2 insertions(+), 21 deletions(-) > --- > base-commit: 798bb342e0416d846cf67f4725a3428f39bfb96b > change-id: 20241202-hpd_display_off-6051aa510f23 > > Best regards, > -- > Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx> > -- With best wishes Dmitry
