[PATCH] drm: Don't try and disable an encoder that was never enabled

[Chris Wilson]

Prevents code that assumes that the encoder is active when asked to be
disabled from dying a horrible death.

Reported-by: Daniel Vetter <daniel.vetter at ffwll.ch>
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Dave Airlie <airlied at redhat.com>
---
 drivers/gpu/drm/drm_crtc_helper.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/gpu/drm/drm_crtc_helper.c 
b/drivers/gpu/drm/drm_crtc_helper.c
index 7ca5935..bede10a 100644
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -241,7 +241,7 @@ void drm_helper_disable_unused_functions(struct drm_device 
*dev)
        }

        list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
-               if (!drm_helper_encoder_in_use(encoder)) {
+               if (encoder->crtc && !drm_helper_encoder_in_use(encoder)) {
                        drm_encoder_disable(encoder);
                        /* disconnector encoder from any connector */
                        encoder->crtc = NULL;
-- 
1.7.2.3