Re: [PATCH v11 36/36] media: v4l2-subdev: Add v4l2_subdev_s_stream_helper() function

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 16/03/2022 14:10, Jacopo Mondi wrote:
Hi Laurent,

On Tue, Mar 01, 2022 at 06:11:56PM +0200, Tomi Valkeinen wrote:
From: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

The v4l2_subdev_s_stream_helper() helper can be used by subdevs that
implement the stream-aware .enable_streams() and .disable_streams()
operations to implement .s_stream(). This is limited to subdevs that
have a single source pad.

Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
---
  drivers/media/v4l2-core/v4l2-subdev.c | 40 +++++++++++++++++++++++++++
  include/media/v4l2-subdev.h           | 17 ++++++++++++
  2 files changed, 57 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index f75a1995a70b..270445821f06 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -1914,6 +1914,46 @@ int v4l2_subdev_disable_streams(struct v4l2_subdev *sd, u32 pad,
  }
  EXPORT_SYMBOL_GPL(v4l2_subdev_disable_streams);

+int v4l2_subdev_s_stream_helper(struct v4l2_subdev *sd, int enable)
+{
+	struct v4l2_subdev_state *state;
+	struct v4l2_subdev_route *route;
+	struct media_pad *pad;
+	u64 source_mask = 0;
+	int pad_index = -1;
+
+	/*
+	 * Find the source pad. This helper is meant for subdevs that have a
+	 * single source pad, so failures shouldn't happen, but catch them
+	 * loudly nonetheless as they indicate a driver bug.
+	 */
+	media_entity_for_each_pad(&sd->entity, pad) {
+		if (pad->flags & MEDIA_PAD_FL_SOURCE) {
+			pad_index = pad->index;
+			break;
+		}
+	}
+
+	if (WARN_ON(pad_index == -1))
+		return -EINVAL;
+
+	/*
+	 * As there's a single source pad, just collect all the source streams.
+	 */
+	state = v4l2_subdev_lock_and_get_active_state(sd);
+
+	for_each_active_route(&state->routing, route)
+		source_mask |= BIT(route->source_stream);
+
+	v4l2_subdev_unlock_state(state);
+
+	if (enable)
+		return v4l2_subdev_enable_streams(sd, pad_index, source_mask);
+	else
+		return v4l2_subdev_disable_streams(sd, pad_index, source_mask);

Or
         return enable ? ...
                       : ... ;

I'm not sure if that's any better...

+}
+EXPORT_SYMBOL_GPL(v4l2_subdev_s_stream_helper);
+
  #endif /* CONFIG_MEDIA_CONTROLLER */

  void v4l2_subdev_init(struct v4l2_subdev *sd, const struct v4l2_subdev_ops *ops)
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index bb1713863973..817452ec30bb 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -1674,6 +1674,23 @@ int v4l2_subdev_enable_streams(struct v4l2_subdev *sd, u32 pad,
  int v4l2_subdev_disable_streams(struct v4l2_subdev *sd, u32 pad,
  				u64 streams_mask);

+/**
+ * v4l2_subdev_s_stream_helper() - Helper to implement the subdev s_stream
+ *	operation using enable_streams and disable_streams
+ * @sd: The subdevice
+ * @enable: Enable to disable streaming

Enable or disable

Thanks.

 Tomi



[Index of Archives]     [Linux Input]     [Video for Linux]     [Gstreamer Embedded]     [Mplayer Users]     [Linux USB Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Yosemite Backpacking]

  Powered by Linux