drm: use dev_name as default unique name in drm_dev_alloc()

The following code pattern exists in some DRM drivers:

    ddev = drm_dev_alloc(&driver, parent_dev);
    drm_dev_set_unique(ddev, dev_name(parent_dev));

(Sometimes dev_name(ddev->dev) is used, which is the same.)

As suggested in
http://lists.freedesktop.org/archives/dri-devel/2015-December/096441.html,
the unique name of a new DRM device can be set as dev_name(parent_dev)
when parent_dev is not NULL (vgem is a special case).
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c

@@ -738,10 +738,6 @@ static int atmel_hlcdc_dc_drm_probe(struct platform_device *pdev)
 	if (!ddev)
 		return -ENOMEM;
 
-	ret = drm_dev_set_unique(ddev, dev_name(ddev->dev));
-	if (ret)
-		goto err_unref;
-
 	ret = atmel_hlcdc_dc_load(ddev);
 	if (ret)
 		goto err_unref;

drivers/gpu/drm/drm_drv.c

@@ -633,8 +633,17 @@ struct drm_device *drm_dev_alloc(struct drm_driver *driver,
 		}
 	}
 
+	if (parent) {
+		ret = drm_dev_set_unique(dev, dev_name(parent));
+		if (ret)
+			goto err_setunique;
+	}
+
 	return dev;
 
+err_setunique:
+	if (drm_core_check_feature(dev, DRIVER_GEM))
+		drm_gem_destroy(dev);
 err_ctxbitmap:
 	drm_legacy_ctxbitmap_cleanup(dev);
 	drm_ht_remove(&dev->map_hash);

drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c

@@ -363,7 +363,6 @@ static int fsl_dcu_drm_probe(struct platform_device *pdev)
 	fsl_dev->np = dev->of_node;
 	drm->dev_private = fsl_dev;
 	dev_set_drvdata(dev, fsl_dev);
-	drm_dev_set_unique(drm, dev_name(dev));
 
 	ret = drm_dev_register(drm, 0);
 	if (ret < 0)

drivers/gpu/drm/nouveau/nouveau_drm.c

@@ -1046,10 +1046,6 @@ nouveau_platform_device_create(const struct nvkm_device_tegra_func *func,
 		goto err_free;
 	}
 
-	err = drm_dev_set_unique(drm, dev_name(&pdev->dev));
-	if (err < 0)
-		goto err_free;
-
 	drm->platformdev = pdev;
 	platform_set_drvdata(pdev, drm);
 

drivers/gpu/drm/rockchip/rockchip_drm_drv.c

@@ -450,10 +450,6 @@ static int rockchip_drm_bind(struct device *dev)
 	if (!drm)
 		return -ENOMEM;
 
-	ret = drm_dev_set_unique(drm, dev_name(dev));
-	if (ret)
-		goto err_free;
-
 	ret = drm_dev_register(drm, 0);
 	if (ret)
 		goto err_free;

drivers/gpu/drm/tegra/drm.c

@@ -991,7 +991,6 @@ static int host1x_drm_probe(struct host1x_device *dev)
 	if (!drm)
 		return -ENOMEM;
 
-	drm_dev_set_unique(drm, dev_name(&dev->dev));
 	dev_set_drvdata(&dev->dev, drm);
 
 	err = drm_dev_register(drm, 0);

drivers/gpu/drm/vc4/vc4_drv.c

@@ -184,8 +184,6 @@ static int vc4_drm_bind(struct device *dev)
 	vc4->dev = drm;
 	drm->dev_private = vc4;
 
-	drm_dev_set_unique(drm, dev_name(dev));
-
 	vc4_bo_cache_init(drm);
 
 	drm_mode_config_init(drm);