[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 <tzimmerm...@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