From: Ville Syrjälä Date: Wed, 29 May 2019 11:02:04 +0000 (+0300) Subject: drm/edid: Ignore "DFP 1.x" bit for EDID 1.2 and earlier X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=3bde449f0bf10e2660ad2858a0334f0eccf21a1c;p=openwrt%2Fstaging%2Fblogic.git drm/edid: Ignore "DFP 1.x" bit for EDID 1.2 and earlier From VESA EDID implementation guide v1.0: "For EDID version 1 revision 2 or earlier data structures when offset 14h bit 7 is set to one, the value of bits 6-0 are undefined, and therefore cannot be interpreted to mean anything." And since EDID 1.4 redefines that bit let's consult it only for EDID 1.3. Cc: Mario Kleiner Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20190529110204.2384-2-ville.syrjala@linux.intel.com Reviewed-by: Alex Deucher Reviewed-by: Mario Kleiner --- diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index dd601ed6a30e..c3296a72fff9 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -4569,8 +4569,8 @@ u32 drm_add_display_info(struct drm_connector *connector, const struct edid *edi * tells us to assume 8 bpc color depth if the EDID doesn't have * extensions which tell otherwise. */ - if ((info->bpc == 0) && (edid->revision < 4) && - (edid->input & DRM_EDID_DIGITAL_DFP_1_X)) { + if (info->bpc == 0 && edid->revision == 3 && + edid->input & DRM_EDID_DIGITAL_DFP_1_X) { info->bpc = 8; DRM_DEBUG("%s: Assigning DFP sink color depth as %d bpc.\n", connector->name, info->bpc);