From dde499d3cf6edea946ff59cb5d72e4f9ef21f3fd Mon Sep 17 00:00:00 2001 From: Maarten Lankhorst Date: Tue, 28 Nov 2017 12:16:03 +0100 Subject: [PATCH] drm/fb_helper: Disable all crtc's when initial setup fails. commit 52dd06506e9bbc2a37b352df7dfc5468f8da21fd upstream. 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") Reported-by: Thomas Voegtle Tested-by: Thomas Voegtle Reviewed-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20171128111603.62757-1-maarten.lankhorst@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- 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 1b8f013ffa65..5e93589c335c 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; } -- 2.20.1