[PATCH v2 4/5] drm/gud: Set struct drm_device.dma_dev

[Thomas Zimmermann]

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 at suse.de>
---
 drivers/gpu/drm/gud/gud_drv.c      | 33 ++++++++----------------------
 drivers/gpu/drm/gud/gud_internal.h |  1 -
 2 files changed, 9 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/gud/gud_drv.c b/drivers/gpu/drm/gud/gud_drv.c
index cb405771d6e2..5385a2126e45 100644
--- a/drivers/gpu/drm/gud/gud_drv.c
+++ b/drivers/gpu/drm/gud/gud_drv.c
@@ -309,21 +309,6 @@ static int gud_get_properties(struct gud_device *gdrm)
 	return ret;
 }
 
-/*
- * 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 *gud_gem_prime_import(struct drm_device *drm, struct dma_buf *dma_buf)
-{
-	struct gud_device *gdrm = to_gud_device(drm);
-
-	if (!gdrm->dmadev)
-		return ERR_PTR(-ENODEV);
-
-	return drm_gem_prime_import_dev(drm, dma_buf, gdrm->dmadev);
-}
-
 static int gud_stats_debugfs(struct seq_file *m, void *data)
 {
 	struct drm_debugfs_entry *entry = m->private;
@@ -376,7 +361,6 @@ static const struct drm_driver gud_drm_driver = {
 	.driver_features	= DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
 	.fops			= &gud_fops,
 	DRM_GEM_SHMEM_DRIVER_OPS,
-	.gem_prime_import	= gud_gem_prime_import,
 	DRM_FBDEV_SHMEM_DRIVER_OPS,
 
 	.name			= "gud",
@@ -434,6 +418,7 @@ static int gud_probe(struct usb_interface *intf, const struct usb_device_id *id)
 	size_t max_buffer_size = 0;
 	struct gud_device *gdrm;
 	struct drm_device *drm;
+	struct device *dma_dev;
 	u8 *formats_dev;
 	u32 *formats;
 	int ret, i;
@@ -609,17 +594,19 @@ static int gud_probe(struct usb_interface *intf, const struct usb_device_id *id)
 
 	usb_set_intfdata(intf, gdrm);
 
-	gdrm->dmadev = usb_intf_get_dma_device(intf);
-	if (!gdrm->dmadev)
-		dev_warn(dev, "buffer sharing not supported");
+	dma_dev = usb_intf_get_dma_device(intf);
+	if (dma_dev) {
+		drm_dev_set_dma_dev(drm, dma_dev);
+		put_device(dma_dev);
+	} else {
+		dev_warn(dev, "buffer sharing not supported"); /* not an error */
+	}
 
 	drm_debugfs_add_file(drm, "stats", gud_stats_debugfs, NULL);
 
 	ret = drm_dev_register(drm, 0);
-	if (ret) {
-		put_device(gdrm->dmadev);
+	if (ret)
 		return ret;
-	}
 
 	drm_kms_helper_poll_init(drm);
 
@@ -638,8 +625,6 @@ static void gud_disconnect(struct usb_interface *interface)
 	drm_kms_helper_poll_fini(drm);
 	drm_dev_unplug(drm);
 	drm_atomic_helper_shutdown(drm);
-	put_device(gdrm->dmadev);
-	gdrm->dmadev = NULL;
 }
 
 static int gud_suspend(struct usb_interface *intf, pm_message_t message)
diff --git a/drivers/gpu/drm/gud/gud_internal.h b/drivers/gpu/drm/gud/gud_internal.h
index 0d148a6f27aa..d6fb25388722 100644
--- a/drivers/gpu/drm/gud/gud_internal.h
+++ b/drivers/gpu/drm/gud/gud_internal.h
@@ -16,7 +16,6 @@
 struct gud_device {
 	struct drm_device drm;
 	struct drm_simple_display_pipe pipe;
-	struct device *dmadev;
 	struct work_struct work;
 	u32 flags;
 	const struct drm_format_info *xrgb8888_emulation_format;
-- 
2.48.1