Re: [PATCH 1/7] drm/msm/dp: use dp_ctrl_off_link_stream during PHY compliance test run

[khsieh]

On 2021-07-08 00:03, Stephen Boyd wrote:
> Quoting Kuogee Hsieh (2021-07-06 10:20:14)
> > DP cable should always connect to DPU during the entire PHY compliance
> > testing run. Since DP PHY compliance test is executed at irq_hpd event
> > context, dp_ctrl_off_link_stream() should be used instead of 
> > dp_ctrl_off().
> > dp_ctrl_off() is used for unplug event which is triggered when DP 
> > cable is
> > dis connected.
> >
> > Signed-off-by: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx>
> > ---
>
> Is this
>
> Fixes: f21c8a276c2d ("drm/msm/dp: handle irq_hpd with sink_count = 0 
> correctly")
>
> or
>
> Fixes: c943b4948b58 ("drm/msm/dp: add displayPort driver support")

should be fixes at f21c8a276c2d ("drm/msm/dp: handle irq_hpd with 
sink_count = 0 correctly")

> ? It's not clear how dp_ctrl_off() was working for compliance tests
> before commit f21c8a276c2d.
both dp_ctrl_off() and dp_ctrl_off_link_strea() are work for 
dp_ctrl_process_phy_test_request()
The problem is after dp_ctrl_off(), aux channel is down, hence next phy 
test will failed due to dpcd read failed.
So that cable unplugged and replug back to required to run next test 
case.
dp_ctrl_off_link_stream() will keep aux channel up and other phy test 
case can be continued.



> >  drivers/gpu/drm/msm/dp/dp_ctrl.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c 
> > b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> > index caf71fa..27fb0f0 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
> > +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> > @@ -1530,7 +1530,7 @@ static int 
> > dp_ctrl_process_phy_test_request(struct dp_ctrl_private *ctrl)
> >          * running. Add the global reset just before disabling the
> >          * link clocks and core clocks.
> >          */
> > -       ret = dp_ctrl_off(&ctrl->dp_ctrl);
> > +       ret = dp_ctrl_off_link_stream(&ctrl->dp_ctrl);
> >         if (ret) {
> >                 DRM_ERROR("failed to disable DP controller\n");
> >                 return ret;