For KMS drivers, replace the IRQ check in VBLANK ioctls with a check for
vblank support. IRQs might be enabled wthout vblanking being supported.

This change also removes the DRM framework's only dependency on IRQ state
for non-legacy drivers. For legacy drivers with userspace modesetting,
the original test remains in drm_wait_vblank_ioctl().

v2:
	* keep the old test for legacy drivers in
	  drm_wait_vblank_ioctl() (Daniel)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/drm_irq.c    | 10 +++-------
 drivers/gpu/drm/drm_vblank.c | 13 +++++++++----
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index c3bd664ea733..1d7785721323 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c

@@ -74,10 +74,8 @@
  * only supports devices with a single interrupt on the main device stored in
  * &drm_device.dev and set as the device paramter in drm_dev_alloc().
  *
- * These IRQ helpers are strictly optional. Drivers which roll their own only
- * need to set &drm_device.irq_enabled to signal the DRM core that vblank
- * interrupts are working. Since these helpers don't automatically clean up the
- * requested interrupt like e.g. devm_request_irq() they're not really
+ * These IRQ helpers are strictly optional. Since these helpers don't automatically
+ * clean up the requested interrupt like e.g. devm_request_irq() they're not really
  * recommended.
  */
 

@@ -91,9 +89,7 @@
  * and after the installation.
  *
  * This is the simplified helper interface provided for drivers with no special
- * needs. Drivers which need to install interrupt handlers for multiple
- * interrupts must instead set &drm_device.irq_enabled to signal the DRM core
- * that vblank interrupts are available.
+ * needs.
  *
  * @irq must match the interrupt number that would be passed to request_irq(),
  * if called directly instead of using this helper function.

diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
index 3417e1ac7918..a98a4aad5037 100644
--- a/drivers/gpu/drm/drm_vblank.c
+++ b/drivers/gpu/drm/drm_vblank.c

@@ -1748,8 +1748,13 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data,
 	unsigned int pipe_index;
 	unsigned int flags, pipe, high_pipe;
 
-	if (!dev->irq_enabled)
-		return -EOPNOTSUPP;
+	if  (drm_core_check_feature(dev, DRIVER_MODESET)) {
+		if (!drm_dev_has_vblank(dev))
+			return -EOPNOTSUPP;
+	} else {
+		if (!dev->irq_enabled)
+			return -EOPNOTSUPP;
+	}

 
 	if (vblwait->request.type & _DRM_VBLANK_SIGNAL)
 		return -EINVAL;

@@ -2023,7 +2028,7 @@ int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data,
 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
 		return -EOPNOTSUPP;
 
-	if (!dev->irq_enabled)
+	if (!drm_dev_has_vblank(dev))
 		return -EOPNOTSUPP;
 
 	crtc = drm_crtc_find(dev, file_priv, get_seq->crtc_id);

@@ -2082,7 +2087,7 @@ int drm_crtc_queue_sequence_ioctl(struct drm_device *dev, void *data,
 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
 		return -EOPNOTSUPP;
 
-	if (!dev->irq_enabled)
+	if (!drm_dev_has_vblank(dev))
 		return -EOPNOTSUPP;
 
 	crtc = drm_crtc_find(dev, file_priv, queue_seq->crtc_id);

-- 
2.32.0