From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932307AbdK1Ltv (ORCPT ); Tue, 28 Nov 2017 06:49:51 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:40903 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752392AbdK1Ltr (ORCPT ); Tue, 28 Nov 2017 06:49:47 -0500 X-Google-Smtp-Source: AGs4zMbstyIg4ONhyPimgHly3ISgPEfkdgqqsIRxl6bz+QbFQh38J7gwvvI8H+KQrsbqn/H4LkJt1w== Date: Tue, 28 Nov 2017 12:49:43 +0100 From: Daniel Vetter To: Maarten Lankhorst Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, daniel.vetter@ffwll.ch, Thomas Voegtle , intel-gfx@lists.freedesktop.org, stable@vger.kernel.org Subject: Re: [PATCH] drm/fb_helper: Disable all crtc's when initial setup fails. Message-ID: <20171128114943.dn4hpgxb6st3ng23@phenom.ffwll.local> Mail-Followup-To: Maarten Lankhorst , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Thomas Voegtle , intel-gfx@lists.freedesktop.org, stable@vger.kernel.org References: <20171128111603.62757-1-maarten.lankhorst@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171128111603.62757-1-maarten.lankhorst@linux.intel.com> X-Operating-System: Linux phenom 4.13.0-1-amd64 User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 28, 2017 at 12:16:03PM +0100, Maarten Lankhorst wrote: > Some drivers like i915 start with crtc's enabled, but with deferred > fbcon setup they were no longer disabled as part of fbdev setup. > Headless units could no longer enter pc3 state because the crtc was > still enabled. > > Fix this by calling restore_fbdev_mode when we would have called > it otherwise once during initial fbdev setup. > > Signed-off-by: Maarten Lankhorst > Fixes: ca91a2758fce ("drm/fb-helper: Support deferred setup") Please use dim fixes to get a more complete Cc: list for regression fixes. > Cc: # v4.14+ > Reported-by: Thomas Voegtle Reviewed-by: Daniel Vetter But please confirm with the reporter that it indeed fixes the issue before pushing. -Daniel > --- > drivers/gpu/drm/drm_fb_helper.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c > index 07374008f146..e56166334455 100644 > --- a/drivers/gpu/drm/drm_fb_helper.c > +++ b/drivers/gpu/drm/drm_fb_helper.c > @@ -1809,6 +1809,10 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, > > if (crtc_count == 0 || sizes.fb_width == -1 || sizes.fb_height == -1) { > DRM_INFO("Cannot find any crtc or sizes\n"); > + > + /* First time: disable all crtc's.. */ > + if (!fb_helper->deferred_setup && !READ_ONCE(fb_helper->dev->master)) > + restore_fbdev_mode(fb_helper); > return -EAGAIN; > } > > -- > 2.15.0 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch