[PATCH 2/4] drm: BUG_ON if passing NULL parent to drm_dev_init

[Emil Velikov]

From: Emil Velikov <emil.velikov at collabora.com>

Previous commit removed the only reason why we were allowing NULL as
a parent device. With that resolved, we can enforce nobody else does
that mistake.

With that we can drop the ugly drm_dev_set_unique workaround.

Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
Cc: Deepak Sharma <deepak.sharma at amd.com>
Signed-off-by: Emil Velikov <emil.velikov at collabora.com>
---
 drivers/gpu/drm/drm_drv.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index a1b9338736e3..88da984ff9eb 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -432,8 +432,6 @@ static void drm_fs_inode_free(struct inode *inode)
  * The initial ref-count of the object is 1. Use drm_dev_get() and
  * drm_dev_put() to take and drop further ref-counts.
  *
- * Note that for purely virtual devices @parent can be NULL.
- *
  * Drivers that do not want to allocate their own device struct
  * embedding &struct drm_device can call drm_dev_alloc() instead. For drivers
  * that do embed &struct drm_device it must be placed first in the overall
@@ -458,6 +456,8 @@ int drm_dev_init(struct drm_device *dev,
 		return -ENODEV;
 	}
 
+	BUG_ON(parent == NULL);
+
 	kref_init(&dev->ref);
 	dev->dev = parent;
 	dev->driver = driver;
@@ -506,9 +506,7 @@ int drm_dev_init(struct drm_device *dev,
 		}
 	}
 
-	/* Use the parent device name as DRM device unique identifier, but fall
-	 * back to the driver name for virtual devices like vgem. */
-	ret = drm_dev_set_unique(dev, parent ? dev_name(parent) : driver->name);
+	ret = drm_dev_set_unique(dev, dev_name(parent));
 	if (ret)
 		goto err_setunique;
 
-- 
2.16.0