Commit dde499d3 authored by Maarten Lankhorst's avatar Maarten Lankhorst Committed by Greg Kroah-Hartman

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: 's avatarMaarten Lankhorst <>
Fixes: ca91a275 ("drm/fb-helper: Support deferred setup")
Reported-by: 's avatarThomas Voegtle <>
Tested-by: 's avatarThomas Voegtle <>
Reviewed-by: 's avatarDaniel Vetter <>
Link: 's avatarGreg Kroah-Hartman <>
parent e4c84b50
......@@ -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))
return -EAGAIN;
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