drm: Make drm_connector_register() safe against multiple calls

Protect against drivers that may try to register the connector more
than once, or who try to unregister it multiple times.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Airlie <airlied@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1465993109-19523-4-git-send-email-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2016-06-15 13:17:48 +01:00 committed by Daniel Vetter
parent aaf285e2e0
commit 40daac6136
2 changed files with 11 additions and 0 deletions

View File

@ -984,6 +984,9 @@ int drm_connector_register(struct drm_connector *connector)
{
int ret;
if (connector->registered)
return 0;
ret = drm_sysfs_connector_add(connector);
if (ret)
return ret;
@ -1001,6 +1004,7 @@ int drm_connector_register(struct drm_connector *connector)
drm_mode_object_register(connector->dev, &connector->base);
connector->registered = true;
return 0;
err_debugfs:
@ -1019,11 +1023,16 @@ EXPORT_SYMBOL(drm_connector_register);
*/
void drm_connector_unregister(struct drm_connector *connector)
{
if (!connector->registered)
return;
if (connector->funcs->early_unregister)
connector->funcs->early_unregister(connector);
drm_sysfs_connector_remove(connector);
drm_debugfs_connector_remove(connector);
connector->registered = false;
}
EXPORT_SYMBOL(drm_connector_unregister);

View File

@ -1193,6 +1193,7 @@ struct drm_encoder {
* @interlace_allowed: can this connector handle interlaced modes?
* @doublescan_allowed: can this connector handle doublescan?
* @stereo_allowed: can this connector handle stereo modes?
* @registered: is this connector exposed (registered) with userspace?
* @modes: modes available on this connector (from fill_modes() + user)
* @status: one of the drm_connector_status enums (connected, not, or unknown)
* @probed_modes: list of modes derived directly from the display
@ -1249,6 +1250,7 @@ struct drm_connector {
bool interlace_allowed;
bool doublescan_allowed;
bool stereo_allowed;
bool registered;
struct list_head modes; /* list of modes on this connector */
enum drm_connector_status status;