1 files changed, 19 insertions, 4 deletions

diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 9689f38a0af1..b15fa9930f30 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -176,7 +176,10 @@ struct v4l2_subdev_io_pin_config {
  * @s_register: callback for VIDIOC_DBG_S_REGISTER() ioctl handler code.
  *
  * @s_power: puts subdevice in power saving mode (on == 0) or normal operation
- *	mode (on == 1).
+ *	mode (on == 1). DEPRECATED. See
+ *	Documentation/driver-api/media/camera-sensor.rst . pre_streamon and
+ *	post_streamoff callbacks can be used for e.g. setting the bus to LP-11
+ *	mode before s_stream is called.
  *
  * @interrupt_service_routine: Called by the bridge chip's interrupt service
  *	handler, when an interrupt status has be raised due to this subdev,
@@ -358,7 +361,11 @@ struct v4l2_mbus_frame_desc_entry {
 	} bus;
 };
 
-#define V4L2_FRAME_DESC_ENTRY_MAX	4
+ /*
+  * If this number is too small, it should be dropped altogether and the
+  * API switched to a dynamic number of frame descriptor entries.
+  */
+#define V4L2_FRAME_DESC_ENTRY_MAX	8
 
 /**
  * enum v4l2_mbus_frame_desc_type - media bus frame description type
@@ -433,8 +440,10 @@ enum v4l2_subdev_pre_streamon_flags {
  * @g_input_status: get input status. Same as the status field in the
  *	&struct v4l2_input
  *
- * @s_stream: used to notify the driver that a video stream will start or has
- *	stopped.
+ * @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.
  *
  * @g_pixelaspect: callback to return the pixelaspect ratio.
  *
@@ -1046,6 +1055,8 @@ v4l2_subdev_get_pad_format(struct v4l2_subdev *sd,
 			   struct v4l2_subdev_state *state,
 			   unsigned int pad)
 {
+	if (WARN_ON(!state))
+		return NULL;
 	if (WARN_ON(pad >= sd->entity.num_pads))
 		pad = 0;
 	return &state->pads[pad].try_fmt;
@@ -1064,6 +1075,8 @@ v4l2_subdev_get_pad_crop(struct v4l2_subdev *sd,
 			 struct v4l2_subdev_state *state,
 			 unsigned int pad)
 {
+	if (WARN_ON(!state))
+		return NULL;
 	if (WARN_ON(pad >= sd->entity.num_pads))
 		pad = 0;
 	return &state->pads[pad].try_crop;
@@ -1082,6 +1095,8 @@ v4l2_subdev_get_pad_compose(struct v4l2_subdev *sd,
 			    struct v4l2_subdev_state *state,
 			    unsigned int pad)
 {
+	if (WARN_ON(!state))
+		return NULL;
 	if (WARN_ON(pad >= sd->entity.num_pads))
 		pad = 0;
 	return &state->pads[pad].try_compose;