drm/i915: suspend/resume GEM when KMS is active

In the KMS case, we need to suspend/resume GEM as well. So on suspend, make
sure we idle GEM and stop any new rendering from coming in, and on resume,
re-init the framebuffer and clear the suspended flag.

Signed-off-by: Jesse Barnes <[e-mail]>
Signed-off-by: Eric Anholt <[e-mail]>
Signed-off-by: Dave Airlie <[e-mail]>

drivers/gpu/drm/i915/i915_drv.c

···
  *
  */
 
+#include <linux/device.h>
 #include "drmP.h"
 #include "drm.h"
 #include "i915_drm.h"
···
 
 	i915_save_state(dev);
 
+	/* If KMS is active, we do the leavevt stuff here */
+	if (drm_core_check_feature(dev, DRIVER_MODESET) && i915_gem_idle(dev)) {
+		dev_err(&dev->pdev->dev, "GEM idle failed, aborting suspend\n");
+		return -EBUSY;
+	}
+
 	intel_opregion_free(dev);
 
 	if (state.event == PM_EVENT_SUSPEND) {
···
 
 static int i915_resume(struct drm_device *dev)
 {
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	int ret = 0;
+
 	pci_set_power_state(dev->pdev, PCI_D0);
 	pci_restore_state(dev->pdev);
 	if (pci_enable_device(dev->pdev))
···
 
 	intel_opregion_init(dev);
 
-	return 0;
+	/* KMS EnterVT equivalent */
+	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
+		mutex_lock(&dev->struct_mutex);
+		dev_priv->mm.suspended = 0;
+
+		ret = i915_gem_init_ringbuffer(dev);
+		if (ret != 0)
+			ret = -1;
+		mutex_unlock(&dev->struct_mutex);
+	}
+
+	return ret;
 }
 
 static struct vm_operations_struct i915_gem_vm_ops = {

drivers/gpu/drm/i915/i915_drv.h

···
 void i915_gem_cleanup_ringbuffer(struct drm_device *dev);
 int i915_gem_do_init(struct drm_device *dev, unsigned long start,
 		     unsigned long end);
+int i915_gem_idle(struct drm_device *dev);
 int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf);
 int i915_gem_object_set_to_gtt_domain(struct drm_gem_object *obj,
 				      int write);

drivers/gpu/drm/i915/i915_gem.c

···
 	return 0;
 }
 
-static int
+int
 i915_gem_idle(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = dev->dev_private;