From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail333.us4.mandrillapp.com ([205.201.137.77]:43800 "EHLO mail333.us4.mandrillapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756272AbcCAX5U (ORCPT ); Tue, 1 Mar 2016 18:57:20 -0500 Received: from pmta03.dal05.mailchimp.com (127.0.0.1) by mail333.us4.mandrillapp.com id hqom60174noe for ; Tue, 1 Mar 2016 23:54:57 +0000 (envelope-from ) From: Greg Kroah-Hartman Subject: [PATCH 4.4 218/342] drm/i915: intel_hpd_init(): Fix suspend/resume reprobing To: Cc: Greg Kroah-Hartman , , Lyude , Daniel Vetter , Jani Nikula Message-Id: <20160301234534.974750985@linuxfoundation.org> In-Reply-To: <20160301234527.990448862@linuxfoundation.org> References: <20160301234527.990448862@linuxfoundation.org> Date: Tue, 01 Mar 2016 23:54:57 +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: Lyude commit 2dc2f761dea65069485110d24eaa5b0d5d808b07 upstream. This fixes reprobing of display connectors on resume. After some talking with danvet on IRC, I learned that calling drm_helper_hpd_irq_event() does actually trigger a full reprobe of each connector's status. It turns out this is the actual reason reprobing on resume hasn't been working (this was observed on a T440s): - We call hpd_init() - We check each connector for a couple of things before marking connector->polled with DRM_CONNECTOR_POLL_HPD, one of which is an active encoder. Of course, a disconnected port won't have an active encoder, so we don't add the flag to any of the connectors. - We call drm_helper_hpd_irq_event() - drm_helper_irq_event() checks each connector for the DRM_CONNECTOR_POLL_HPD flag. The only one that has it is eDP-1, so we skip reprobing each connector except that one. In addition, we also now avoid setting connector->polled to DRM_CONNECTOR_POLL_HPD for MST connectors, since their reprobing is handled by the mst helpers. This is probably what was originally intended to happen here. Changes since V1: * Use the explanation of the issue as the commit message instead * Change the title of the commit, since this does more then just stop a check for an encoder now * Add "Fixes" line for the patch that introduced this regression * Don't enable DRM_CONNECTOR_POLL_HPD for mst connectors Changes since V2: * Put patch changelog above Signed-off-by * Follow Daniel Vetter's suggestion for making the code here a bit more legible Fixes: 0e32b39ceed6 ("drm/i915: add DP 1.2 MST support (v0.7)") Signed-off-by: Lyude Link: http://patchwork.freedesktop.org/patch/msgid/1452181408-14777-1-git-send-email-cpaul@redhat.com Signed-off-by: Daniel Vetter (cherry picked from commit 07c519134417d92c2e1a536e2b66d4ffff4b3be0) Signed-off-by: Jani Nikula Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/intel_hotplug.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/i915/intel_hotplug.c +++ b/drivers/gpu/drm/i915/intel_hotplug.c @@ -468,9 +468,14 @@ void intel_hpd_init(struct drm_i915_priv list_for_each_entry(connector, &mode_config->connector_list, head) { struct intel_connector *intel_connector = to_intel_connector(connector); connector->polled = intel_connector->polled; - if (connector->encoder && !connector->polled && I915_HAS_HOTPLUG(dev) && intel_connector->encoder->hpd_pin > HPD_NONE) - connector->polled = DRM_CONNECTOR_POLL_HPD; + + /* MST has a dynamic intel_connector->encoder and it's reprobing + * is all handled by the MST helpers. */ if (intel_connector->mst_port) + continue; + + if (!connector->polled && I915_HAS_HOTPLUG(dev) && + intel_connector->encoder->hpd_pin > HPD_NONE) connector->polled = DRM_CONNECTOR_POLL_HPD; }