From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail333.us4.mandrillapp.com ([205.201.137.77]:58676 "EHLO mail333.us4.mandrillapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756232AbcCAX5L (ORCPT ); Tue, 1 Mar 2016 18:57:11 -0500 Received: from pmta03.dal05.mailchimp.com (127.0.0.1) by mail333.us4.mandrillapp.com id hqom5e174no3 for ; Tue, 1 Mar 2016 23:54:52 +0000 (envelope-from ) From: Greg Kroah-Hartman Subject: [PATCH 4.4 203/342] drm/dp/mst: Reverse order of MST enable and clearing VC payload table. To: Cc: Greg Kroah-Hartman , , Andrey Grodzovsky , Harry Wentland , Alex Deucher , Dave Airlie Message-Id: <20160301234534.476542506@linuxfoundation.org> In-Reply-To: <20160301234527.990448862@linuxfoundation.org> References: <20160301234527.990448862@linuxfoundation.org> Date: Tue, 01 Mar 2016 23:54:51 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andrey Grodzovsky commit c175cd16df272119534058f28cbd5eeac6ff2d24 upstream. On DELL U3014 if you clear the table before enabling MST it sometimes hangs the receiver. Signed-off-by: Andrey Grodzovsky Reviewed-by: Harry Wentland Acked-by: Alex Deucher Signed-off-by: Dave Airlie Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/drm_dp_mst_topology.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -1976,6 +1976,12 @@ int drm_dp_mst_topology_mgr_set_mst(stru mgr->mst_primary = mstb; kref_get(&mgr->mst_primary->kref); + ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, + DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); + if (ret < 0) { + goto out_unlock; + } + { struct drm_dp_payload reset_pay; reset_pay.start_slot = 0; @@ -1983,12 +1989,6 @@ int drm_dp_mst_topology_mgr_set_mst(stru drm_dp_dpcd_write_payload(mgr, 0, &reset_pay); } - ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, - DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); - if (ret < 0) { - goto out_unlock; - } - queue_work(system_long_wq, &mgr->work); ret = 0;