udldrmfb only reads the main EDID block, and if that advertises extensions the drm_edid code expects them to be present, and starts reading beyond the buffer udldrmfb passes it. Although it may be possible to read more EDID info with the udl we simpy don't know how, and even if trial and error gets it working on one device, that is no guarantee it will work on other revisions. So this patch does a simple fix in the form of patching the EDID info to report 0 extension blocks, this fixes udldrmfb only doing 1024x768 on monitors with EDID extension blocks. Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- drivers/gpu/drm/udl/udl_connector.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/gpu/drm/udl/udl_connector.c b/drivers/gpu/drm/udl/udl_connector.c index b3b2ced..86538c9 100644 --- a/drivers/gpu/drm/udl/udl_connector.c +++ b/drivers/gpu/drm/udl/udl_connector.c @@ -57,6 +57,14 @@ static int udl_get_modes(struct drm_connector *connector) edid = (struct edid *)udl_get_edid(udl); + /* + * We only read the main block, but if the monitor reports extension + * blocks then the drm edid code expects them to be present, so patch + * the extension count to 0. + */ + edid->checksum += edid->extensions; + edid->extensions = 0; + drm_mode_connector_update_edid_property(connector, edid); ret = drm_add_edid_modes(connector, edid); kfree(edid); -- 1.8.0.2 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
