> -----Original Message----- > From: Intel-gfx <intel-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of Ville Syrjala > Sent: Saturday, January 25, 2020 1:32 AM > To: dri-devel@xxxxxxxxxxxxxxxxxxxxx > Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx; Andres Rodriguez <andresx7@xxxxxxxxx> > Subject: [Intel-gfx] [PATCH 6/8] drm/edid: Add a FIXME about DispID CEA data block > revision > > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > I don't understand what the DispID CEA data block revision means. The spec doesn't > say. I guess some DispID must have a value of >= 3 in there or else we generally > wouldn't even parse the CEA data blocks. Or does all this code actually not do > anything? This signifies the CTA extension revision (byte 1 of the block). As per the spec, seems like Version 1 is legacy and 2 is deprecated. So version >=3 is checked here. Refer section 7.3 of CTA-861-G > Cc: Andres Rodriguez <andresx7@xxxxxxxxx> > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/drm_edid.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index > 0369a54e3d32..fd9b724067a7 100644 > --- a/drivers/gpu/drm/drm_edid.c > +++ b/drivers/gpu/drm/drm_edid.c > @@ -3977,6 +3977,13 @@ cea_db_tag(const u8 *db) static int cea_revision(const > u8 *cea) { > + /* > + * FIXME is this correct for the DispID variant? > + * The DispID spec doesn't really specify whether > + * this is the revision of the CEA extension or > + * the DispID CEA data block. And the only value > + * given as an example is 0. > + */ > return cea[1]; > } > > -- > 2.24.1 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/intel-gfx _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel