The pre-retina MacBook Pro uses an LVDS panel and a gmux controller to switch the panel between its two GPUs. The panel mode in VBIOS is notoriously bogus on these machines. Use drm_get_edid_switcheroo() in lieu of drm_get_edid() on LVDS. This allows us to retrieve the EDID if the outputs are currently muxed to the integrated GPU by temporarily switching the panel's DDC lines to the discrete GPU. This only enables EDID probing on the pre-retina MBP (2008 - 2013). The retina MBP (2012 - present) uses eDP and gmux is not capable of switching AUX separately from the main link on these models. This will be addressed in later patches. List of pre-retina MBPs with dual GPUs, one of them AMD: [MBP 8,2 2011 intel SNB + amd turks pre-retina 15"] [MBP 8,3 2011 intel SNB + amd turks pre-retina 17"] Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115 Tested-by: William Brown <william@xxxxxxxxxxxxxxxx> [MBP 8,2 2011 intel SNB + amd turks pre-retina 15"] Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx> --- drivers/gpu/drm/radeon/radeon_connectors.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c index 5a2cafb..569f63c 100644 --- a/drivers/gpu/drm/radeon/radeon_connectors.c +++ b/drivers/gpu/drm/radeon/radeon_connectors.c @@ -344,6 +344,10 @@ static void radeon_connector_get_edid(struct drm_connector *connector) else if (radeon_connector->ddc_bus) radeon_connector->edid = drm_get_edid(&radeon_connector->base, &radeon_connector->ddc_bus->adapter); + } else if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS && + radeon_connector->ddc_bus) { + radeon_connector->edid = drm_get_edid_switcheroo(&radeon_connector->base, + &radeon_connector->ddc_bus->adapter); } else if (radeon_connector->ddc_bus) { radeon_connector->edid = drm_get_edid(&radeon_connector->base, &radeon_connector->ddc_bus->adapter); -- 1.8.5.2 (Apple Git-48) _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel