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>

drivers/gpu/drm/Kconfig

@@ -102,6 +102,7 @@ config DRM_I915
 	select BACKLIGHT_CLASS_DEVICE if ACPI
 	select INPUT if ACPI
 	select ACPI_VIDEO if ACPI
+	select ACPI_BUTTON if ACPI
 	help
 	  Choose this option if you have a system that has Intel 830M, 845G,
 	  852GM, 855GM 865G or 915G integrated graphics.  If M is selected, the

drivers/gpu/drm/i915/i915_drv.h

@@ -222,6 +222,8 @@ typedef struct drm_i915_private {
 	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 */

drivers/gpu/drm/i915/intel_display.c

@@ -24,6 +24,8 @@
  *	Eric Anholt <eric@anholt.net>
  */
 
+#include <linux/module.h>
+#include <linux/input.h>
 #include <linux/i2c.h>
 #include <linux/kernel.h>
 #include "drmP.h"

drivers/gpu/drm/i915/intel_lvds.c

@@ -27,6 +27,7 @@
  *      Jesse Barnes <jesse.barnes@intel.com>
  */
 
+#include <acpi/button.h>
 #include <linux/dmi.h>
 #include <linux/i2c.h>
 #include "drmP.h"
@@ -632,6 +633,19 @@ static int intel_lvds_get_modes(struct drm_connector *connector)
 	return 0;
 }
 
+static int intel_lid_notify(struct notifier_block *nb, unsigned long val,
+			    void *unused)
+{
+	struct drm_i915_private *dev_priv =
+		container_of(nb, struct drm_i915_private, lid_notifier);
+	struct drm_device *dev = dev_priv->dev;
+
+	if (acpi_lid_open())
+		drm_helper_resume_force_mode(dev);
+
+	return NOTIFY_OK;
+}
+
 /**
  * intel_lvds_destroy - unregister and free LVDS structures
  * @connector: connector to free
@@ -641,10 +655,14 @@ static int intel_lvds_get_modes(struct drm_connector *connector)
  */
 static void intel_lvds_destroy(struct drm_connector *connector)
 {
+	struct drm_device *dev = connector->dev;
 	struct intel_output *intel_output = to_intel_output(connector);
+	struct drm_i915_private *dev_priv = dev->dev_private;
 
 	if (intel_output->ddc_bus)
 		intel_i2c_destroy(intel_output->ddc_bus);
+	if (dev_priv->lid_notifier.notifier_call)
+		acpi_lid_notifier_unregister(&dev_priv->lid_notifier);
 	drm_sysfs_connector_remove(connector);
 	drm_connector_cleanup(connector);
 	kfree(connector);
@@ -1011,6 +1029,11 @@ out:
 		pwm |= PWM_PCH_ENABLE;
 		I915_WRITE(BLC_PWM_PCH_CTL1, pwm);
 	}
+	dev_priv->lid_notifier.notifier_call = intel_lid_notify;
+	if (acpi_lid_notifier_register(&dev_priv->lid_notifier)) {
+		DRM_DEBUG("lid notifier registration failed\n");
+		dev_priv->lid_notifier.notifier_call = NULL;
+	}
 	drm_sysfs_connector_add(connector);
 	return;