[media] media: s3c-camif: fix deadlock on driver probe()

Commit 0c426c472b5585ed6e59160359c979506d45ae49 ("[media] media: Always
keep a graph walk large enough around") changed
media_device_register_entity() function to take mdev->graph_mutex. This
causes deadlock in driver probe, which calls (indirectly) this function
with ->graph_mutex taken. This patch removes taking ->graph_mutex in
driver probe to avoid deadlock. Other drivers don't take ->graph_mutex
for entity registration, so this change should be safe.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

diff --git a/drivers/media/platform/s3c-camif/camif-core.c b/drivers/media/platform/s3c-camif/camif-core.c
index 0b44b9a..af237af 100644 (file)
--- a/drivers/media/platform/s3c-camif/camif-core.c
+++ b/drivers/media/platform/s3c-camif/camif-core.c
@@ -493,21 +493,17 @@ static int s3c_camif_probe(struct platform_device *pdev)
        if (ret < 0)
                goto err_sens;
 
-       mutex_lock(&camif->media_dev.graph_mutex);
-
        ret = v4l2_device_register_subdev_nodes(&camif->v4l2_dev);
        if (ret < 0)
-               goto err_unlock;
+               goto err_sens;
 
        ret = camif_register_video_nodes(camif);
        if (ret < 0)
-               goto err_unlock;
+               goto err_sens;
 
        ret = camif_create_media_links(camif);
        if (ret < 0)
-               goto err_unlock;
-
-       mutex_unlock(&camif->media_dev.graph_mutex);
+               goto err_sens;
 
        ret = media_device_register(&camif->media_dev);
        if (ret < 0)
@@ -516,8 +512,6 @@ static int s3c_camif_probe(struct platform_device *pdev)
        pm_runtime_put(dev);
        return 0;
 
-err_unlock:
-       mutex_unlock(&camif->media_dev.graph_mutex);
 err_sens:
        v4l2_device_unregister(&camif->v4l2_dev);
        media_device_unregister(&camif->media_dev);