From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755667AbcA2B4q (ORCPT ); Thu, 28 Jan 2016 20:56:46 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:33050 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753829AbcA2BWM (ORCPT ); Thu, 28 Jan 2016 20:22:12 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Lyude , Daniel Vetter , Jani Nikula , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 102/210] drm/i915: intel_hpd_init(): Fix suspend/resume reprobing Date: Thu, 28 Jan 2016 17:17:20 -0800 Message-Id: <1454030348-17736-103-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1454030348-17736-1-git-send-email-kamal@canonical.com> References: <1454030348-17736-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19.8-ckt14 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ 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: Kamal Mostafa --- drivers/gpu/drm/i915/i915_irq.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index 247cc18..2c86e0a 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -4478,9 +4478,14 @@ void intel_hpd_init(struct drm_i915_private *dev_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; } -- 1.9.1