drm: mark dma setup/teardown as legacy systems

And hide the checks a bit better. This was already disallowed for
modesetting drivers, so no functinal change here.

Reviewed-by: Eric Anholt <[e-mail]>
Signed-off-by: Daniel Vetter <[e-mail]>
Signed-off-by: Dave Airlie <[e-mail]>

drivers/gpu/drm/drm_dma.c

···
  *
  * Allocate and initialize a drm_device_dma structure.
  */
-int drm_dma_setup(struct drm_device *dev)
+int drm_legacy_dma_setup(struct drm_device *dev)
 {
 	int i;
+
+	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
+	    drm_core_check_feature(dev, DRIVER_MODESET)) {
+		return 0;
+	}
+
+	dev->buf_use = 0;
+	atomic_set(&dev->buf_alloc, 0);
 
 	dev->dma = kzalloc(sizeof(*dev->dma), GFP_KERNEL);
 	if (!dev->dma)
···
  * Free all pages associated with DMA buffers, the buffers and pages lists, and
  * finally the drm_device::dma structure itself.
  */
-void drm_dma_takedown(struct drm_device *dev)
+void drm_legacy_dma_takedown(struct drm_device *dev)
 {
 	struct drm_device_dma *dma = dev->dma;
 	int i, j;
+
+	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA) ||
+	    drm_core_check_feature(dev, DRIVER_MODESET)) {
+		return;
+	}
 
 	if (!dma)
 		return;

drivers/gpu/drm/drm_drv.c

···
 		kfree(vma);
 	}
 
-	if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
-	    !drm_core_check_feature(dev, DRIVER_MODESET))
-		drm_dma_takedown(dev);
+	drm_legacy_dma_takedown(dev);
 
 	dev->dev_mapping = NULL;
 	mutex_unlock(&dev->struct_mutex);

drivers/gpu/drm/drm_fops.c

···
 	atomic_set(&dev->ioctl_count, 0);
 	atomic_set(&dev->vma_count, 0);
 
-	if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
-	    !drm_core_check_feature(dev, DRIVER_MODESET)) {
-		dev->buf_use = 0;
-		atomic_set(&dev->buf_alloc, 0);
-
-		i = drm_dma_setup(dev);
-		if (i < 0)
-			return i;
-	}
+	i = drm_legacy_dma_setup(dev);
+	if (i < 0)
+		return i;
 
 	for (i = 0; i < ARRAY_SIZE(dev->counts); i++)
 		atomic_set(&dev->counts[i], 0);

include/drm/drmP.h

···
 		       struct drm_file *file_priv);
 
 				/* DMA support (drm_dma.h) */
-extern int drm_dma_setup(struct drm_device *dev);
-extern void drm_dma_takedown(struct drm_device *dev);
+extern int drm_legacy_dma_setup(struct drm_device *dev);
+extern void drm_legacy_dma_takedown(struct drm_device *dev);
 extern void drm_free_buffer(struct drm_device *dev, struct drm_buf * buf);
 extern void drm_core_reclaim_buffers(struct drm_device *dev,
 				     struct drm_file *filp);