From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f47.google.com ([74.125.82.47]:38140 "EHLO mail-wm0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751651AbcAGQLB (ORCPT ); Thu, 7 Jan 2016 11:11:01 -0500 Received: by mail-wm0-f47.google.com with SMTP id b14so131062918wmb.1 for ; Thu, 07 Jan 2016 08:11:00 -0800 (PST) Date: Thu, 7 Jan 2016 17:10:59 +0100 From: Daniel Vetter To: Lyude Cc: Daniel Vetter , Jani Nikula , David Airlie , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Benjamin Tissoires , stable@vger.kernel.org Subject: Re: [Intel-gfx] [PATCH v3] drm/i915: intel_hpd_init(): Fix suspend/resume reprobing Message-ID: <20160107161059.GU8076@phenom.ffwll.local> References: <20160106072743.GV8076@phenom.ffwll.local> <1452181408-14777-1-git-send-email-cpaul@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1452181408-14777-1-git-send-email-cpaul@redhat.com> Sender: stable-owner@vger.kernel.org List-ID: On Thu, Jan 07, 2016 at 10:43:28AM -0500, Lyude wrote: > 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)") > Cc: stable@vger.kernel.org > Signed-off-by: Lyude Awesome, and merged to drm-intel. Thanks, Daniel > --- > drivers/gpu/drm/i915/intel_hotplug.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_hotplug.c b/drivers/gpu/drm/i915/intel_hotplug.c > index b177857..d7a6437 100644 > --- 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_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; > } > > -- > 2.5.0 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch