Re: [PATCH v2 5/7] drm/msm/dp: return correct edid checksum after corrupted edid checksum read

[khsieh]

On 2021-07-22 12:23, Stephen Boyd wrote:
> Quoting Kuogee Hsieh (2021-07-13 08:54:05)
> > diff --git a/drivers/gpu/drm/msm/dp/dp_panel.c 
> > b/drivers/gpu/drm/msm/dp/dp_panel.c
> > index 88196f7..0fdb551 100644
> > --- a/drivers/gpu/drm/msm/dp/dp_panel.c
> > +++ b/drivers/gpu/drm/msm/dp/dp_panel.c
> > @@ -303,7 +303,12 @@ void dp_panel_handle_sink_request(struct dp_panel 
> > *dp_panel)
> >         panel = container_of(dp_panel, struct dp_panel_private, 
> > dp_panel);
> >
> >         if (panel->link->sink_request & DP_TEST_LINK_EDID_READ) {
> > -               u8 checksum = 
> > dp_panel_get_edid_checksum(dp_panel->edid);
> > +               u8 checksum;
> > +
> > +               if (dp_panel->edid)
> > +                       checksum = 
> > dp_panel_get_edid_checksum(dp_panel->edid);
> > +               else
> > +                       checksum = 
> > dp_panel->connector->real_edid_checksum;
>
> Is there any reason why we can't use connector->real_edid_checksum all
> the time?
real_edid_checksum only calculated by drm when edid checksum 
vitrification failed after edid read.
In the good edid checksum case (edid verification succeed), 
real_edid_checksum is not calculated by drm.
> >                 dp_link_send_edid_checksum(panel->link, checksum);
> >                 dp_link_send_test_response(panel->link);