The subdev .s_stream() operation must not be called to start an already
started subdev, or stop an already stopped one. This requirement has
never been formally documented. Fix it.
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
include/media/v4l2-subdev.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index d9fca929c10b..282914ea9d45 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -446,7 +446,9 @@ enum v4l2_subdev_pre_streamon_flags {
* @s_stream: start (enabled == 1) or stop (enabled == 0) streaming on the
* sub-device. Failure on stop will remove any resources acquired in
* streaming start, while the error code is still returned by the driver.
- * Also see call_s_stream wrapper in v4l2-subdev.c.
+ * The caller shall track the subdev state, and refrain from starting or
+ * stopping an already started or stopped subdev. AAlso see call_s_stream
+ * wrapper in v4l2-subdev.c.
*
* @g_pixelaspect: callback to return the pixelaspect ratio.
*
--
Regards,
Laurent Pinchart
