drm/i915: force mode set at lid open time

Some laptop platforms will disable pipes and/or planes at lid close time
and not restore them when the lid is opened again.  So catch the lid
event, and if the lid was opened, force a mode restore.

Fixes fdo bug #21230.

Acked-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index df4597d..f2b8d27 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -222,6 +222,8 @@
 	unsigned int edp_support:1;
 	int lvds_ssc_freq;
 
+	struct notifier_block lid_notifier;
+
 	int crt_ddc_bus; /* -1 = unknown, else GPIO to use for CRT DDC */
 	struct drm_i915_fence_reg fence_regs[16]; /* assume 965 */
 	int fence_reg_start; /* 4 if userland hasn't ioctl'd us yet */