From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dave Airlie , Alex Deucher , Sasha Levin Subject: [PATCH 4.4 110/192] [PATCH 114/135] drm/radeon/mst: fix regression in lane/link handling. Date: Mon, 12 Sep 2016 19:00:19 +0200 Message-Id: <20160912152203.608073056@linuxfoundation.org> In-Reply-To: <20160912152158.855601725@linuxfoundation.org> References: <20160912152158.855601725@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit b36f7d26a7fdc0b07b1217368ee09bb8560269f8 ] 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. Cc: stable@vger.kernel.org # v4.4 Signed-off-by: Dave Airlie Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- 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); }