On Tue, Jan 25, 2022 at 10:32:51AM +0100, Maxime Ripard wrote: > Even though we have the other drm_display_info fields reset, the DC > modes are missing. > > This shouldn't be an issue since it's explicitely reset every time a new > EDID is parsed. It's not really obvious that it can't be an issue. I think we might be saved by info->bpc getting reset to 8 by drm_parse_hdmi_vsdb_video(). But the dc_modes bitfields themselves may be left with stale values. Hmm, actually drm_add_display_info() re-populates info->bpc *after* drm_parse_hdmi_vsdb_video() so we could in theory end up with bpc>8 and dc_modes!=0 even if the display doesn't support any HDMI deep color modes. Though I suppose a display that doesn't do deep color but declares its max bpc as >8 is a bit nuts. I could maybe imagine it happening if the display supports >8 bpc with DP but not with HDMI, and doesn't bother customizing the EDID sufficiently for each interface. > > Suggested-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx> Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/drm_edid.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c > index 5251925e3b92..a76224653e6f 100644 > --- a/drivers/gpu/drm/drm_edid.c > +++ b/drivers/gpu/drm/drm_edid.c > @@ -5340,6 +5340,9 @@ drm_reset_display_info(struct drm_connector *connector) > info->rgb_quant_range_selectable = false; > memset(&info->hdmi, 0, sizeof(info->hdmi)); We should probably just move more stuff into that .hdmi struct... > > + info->edid_hdmi_rgb444_dc_modes = 0; > + info->edid_hdmi_ycbcr444_dc_modes = 0; > + > info->non_desktop = 0; > memset(&info->monitor_range, 0, sizeof(info->monitor_range)); > > -- > 2.34.1 -- Ville Syrjälä Intel
