This is a note to let you know that I've just added the patch titled drm/radeon/mst: fix regression in lane/link handling. to the 4.5-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-radeon-mst-fix-regression-in-lane-link-handling.patch and it can be found in the queue-4.5 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From b36f7d26a7fdc0b07b1217368ee09bb8560269f8 Mon Sep 17 00:00:00 2001 From: Dave Airlie <airlied@xxxxxxxxxx> Date: Tue, 22 Mar 2016 09:38:18 +1000 Subject: drm/radeon/mst: fix regression in lane/link handling. From: Dave Airlie <airlied@xxxxxxxxxx> commit b36f7d26a7fdc0b07b1217368ee09bb8560269f8 upstream. The function this used changed in 092c96a8ab9d1bd60ada2ed385cc364ce084180e drm/radeon: fix dp link rate selection (v2) However for MST we should just always train to the max link/rate. Though we probably need to limit this for future hw, in theory radeon won't support it. This fixes my 30" monitor with MST enabled. Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/radeon/radeon_dp_mst.c | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-) --- a/drivers/gpu/drm/radeon/radeon_dp_mst.c +++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c @@ -525,17 +525,9 @@ static bool radeon_mst_mode_fixup(struct drm_mode_set_crtcinfo(adjusted_mode, 0); { struct radeon_connector_atom_dig *dig_connector; - int ret; - dig_connector = mst_enc->connector->con_priv; - ret = radeon_dp_get_dp_link_config(&mst_enc->connector->base, - dig_connector->dpcd, adjusted_mode->clock, - &dig_connector->dp_lane_count, - &dig_connector->dp_clock); - if (ret) { - dig_connector->dp_lane_count = 0; - dig_connector->dp_clock = 0; - } + dig_connector->dp_lane_count = drm_dp_max_lane_count(dig_connector->dpcd); + dig_connector->dp_clock = drm_dp_max_link_rate(dig_connector->dpcd); DRM_DEBUG_KMS("dig clock %p %d %d\n", dig_connector, dig_connector->dp_lane_count, dig_connector->dp_clock); } Patches currently in stable-queue which might be from airlied@xxxxxxxxxx are queue-4.5/drm-radeon-mst-fix-regression-in-lane-link-handling.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html