[PATCH v2] media: staging/imx: do not return error in link_notify for unknown sources

[Steve Longerbeam <slongerbeam@gmail.com>]

imx_media_link_notify() should not return error if the source subdevice
of the link is not found in the list of subdevices that registered via
async. If the subdev has controls they will be inherited via a link_notify
that starts from a known source async subdev.

Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
---
Changes since v1:
 - expanded on commit message and comment.
---
 drivers/staging/media/imx/imx-media-dev.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/media/imx/imx-media-dev.c b/drivers/staging/media/imx/imx-media-dev.c
index b55e5eb..809d92e 100644
--- a/drivers/staging/media/imx/imx-media-dev.c
+++ b/drivers/staging/media/imx/imx-media-dev.c
@@ -508,8 +508,16 @@ static int imx_media_link_notify(struct media_link *link, u32 flags,
 	imxmd = dev_get_drvdata(sd->v4l2_dev->dev);
 
 	imxsd = imx_media_find_subdev_by_sd(imxmd, sd);
-	if (IS_ERR(imxsd))
-		return PTR_ERR(imxsd);
+	if (IS_ERR(imxsd)) {
+		/*
+		 * don't bother refreshing video device controls if the
+		 * source subdev isn't found in the async subdev list. If
+		 * this subdev has controls they will be inherited starting
+		 * from a known async subdev.
+		 */
+		return 0;
+	}
+
 	imxpad = &imxsd->pad[pad_idx];
 
 	/*
-- 
2.7.4