[PATCH 2/4] drm/gm12u320: Set struct drm_device.dma_dev

[Thomas Zimmermann <tzimmermann@xxxxxxx>]

Set the dma_dev field provided by the DRM device. Required for PRIME
dma-buf import. Remove the driver's implementation.

Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
---
 drivers/gpu/drm/tiny/gm12u320.c | 41 +++++++--------------------------
 1 file changed, 8 insertions(+), 33 deletions(-)

diff --git a/drivers/gpu/drm/tiny/gm12u320.c b/drivers/gpu/drm/tiny/gm12u320.c
index 41e9bfb2e2ff..caee35ecaaef 100644
--- a/drivers/gpu/drm/tiny/gm12u320.c
+++ b/drivers/gpu/drm/tiny/gm12u320.c
@@ -86,7 +86,6 @@ MODULE_PARM_DESC(eco_mode, "Turn on Eco mode (less bright, more silent)");
 
 struct gm12u320_device {
 	struct drm_device	         dev;
-	struct device                   *dmadev;
 	struct drm_simple_display_pipe   pipe;
 	struct drm_connector	         conn;
 	unsigned char                   *cmd_buf;
@@ -602,22 +601,6 @@ static const uint64_t gm12u320_pipe_modifiers[] = {
 	DRM_FORMAT_MOD_INVALID
 };
 
-/*
- * FIXME: Dma-buf sharing requires DMA support by the importing device.
- *        This function is a workaround to make USB devices work as well.
- *        See todo.rst for how to fix the issue in the dma-buf framework.
- */
-static struct drm_gem_object *gm12u320_gem_prime_import(struct drm_device *dev,
-							struct dma_buf *dma_buf)
-{
-	struct gm12u320_device *gm12u320 = to_gm12u320(dev);
-
-	if (!gm12u320->dmadev)
-		return ERR_PTR(-ENODEV);
-
-	return drm_gem_prime_import_dev(dev, dma_buf, gm12u320->dmadev);
-}
-
 DEFINE_DRM_GEM_FOPS(gm12u320_fops);
 
 static const struct drm_driver gm12u320_drm_driver = {
@@ -630,7 +613,6 @@ static const struct drm_driver gm12u320_drm_driver = {
 
 	.fops		 = &gm12u320_fops,
 	DRM_GEM_SHMEM_DRIVER_OPS,
-	.gem_prime_import = gm12u320_gem_prime_import,
 	DRM_FBDEV_SHMEM_DRIVER_OPS,
 };
 
@@ -660,8 +642,8 @@ static int gm12u320_usb_probe(struct usb_interface *interface,
 		return PTR_ERR(gm12u320);
 	dev = &gm12u320->dev;
 
-	gm12u320->dmadev = usb_intf_get_dma_device(to_usb_interface(dev->dev));
-	if (!gm12u320->dmadev)
+	dev->dma_dev = usb_intf_get_dma_device(to_usb_interface(dev->dev));
+	if (!dev->dma_dev)
 		drm_warn(dev, "buffer sharing not supported"); /* not an error */
 
 	INIT_DELAYED_WORK(&gm12u320->fb_update.work, gm12u320_fb_update_work);
@@ -669,7 +651,7 @@ static int gm12u320_usb_probe(struct usb_interface *interface,
 
 	ret = drmm_mode_config_init(dev);
 	if (ret)
-		goto err_put_device;
+		return ret;
 
 	dev->mode_config.min_width = GM12U320_USER_WIDTH;
 	dev->mode_config.max_width = GM12U320_USER_WIDTH;
@@ -679,15 +661,15 @@ static int gm12u320_usb_probe(struct usb_interface *interface,
 
 	ret = gm12u320_usb_alloc(gm12u320);
 	if (ret)
-		goto err_put_device;
+		return ret;
 
 	ret = gm12u320_set_ecomode(gm12u320);
 	if (ret)
-		goto err_put_device;
+		return ret;
 
 	ret = gm12u320_conn_init(gm12u320);
 	if (ret)
-		goto err_put_device;
+		return ret;
 
 	ret = drm_simple_display_pipe_init(&gm12u320->dev,
 					   &gm12u320->pipe,
@@ -697,31 +679,24 @@ static int gm12u320_usb_probe(struct usb_interface *interface,
 					   gm12u320_pipe_modifiers,
 					   &gm12u320->conn);
 	if (ret)
-		goto err_put_device;
+		return ret;
 
 	drm_mode_config_reset(dev);
 
 	usb_set_intfdata(interface, dev);
 	ret = drm_dev_register(dev, 0);
 	if (ret)
-		goto err_put_device;
+		return ret;
 
 	drm_client_setup(dev, NULL);
 
 	return 0;
-
-err_put_device:
-	put_device(gm12u320->dmadev);
-	return ret;
 }
 
 static void gm12u320_usb_disconnect(struct usb_interface *interface)
 {
 	struct drm_device *dev = usb_get_intfdata(interface);
-	struct gm12u320_device *gm12u320 = to_gm12u320(dev);
 
-	put_device(gm12u320->dmadev);
-	gm12u320->dmadev = NULL;
 	drm_dev_unplug(dev);
 	drm_atomic_helper_shutdown(dev);
 }
-- 
2.48.1