Parse neighbor remote devices on the video muxes input ports, add them to a
subdev notifier, and register the subdev notifier for the video mux, by
calling v4l2_async_register_fwnode_subdev().
Signed-off-by: Steve Longerbeam <steve_longerbeam@xxxxxxxxxx>
---
Changes since v1:
- add #include <linux/slab.h> for kcalloc() declaration.
drivers/media/platform/video-mux.c | 36 +++++++++++++++++++++++++++++++++++-
1 file changed, 35 insertions(+), 1 deletion(-)
diff --git a/drivers/media/platform/video-mux.c b/drivers/media/platform/video-mux.c
index ee89ad7..b93b0af 100644
--- a/drivers/media/platform/video-mux.c
+++ b/drivers/media/platform/video-mux.c
@@ -21,8 +21,10 @@
#include <linux/of.h>
#include <linux/of_graph.h>
#include <linux/platform_device.h>
+#include <linux/slab.h>
#include <media/v4l2-async.h>
#include <media/v4l2-device.h>
+#include <media/v4l2-fwnode.h>
#include <media/v4l2-subdev.h>
struct video_mux {
@@ -193,6 +195,38 @@ static const struct v4l2_subdev_ops video_mux_subdev_ops = {
.video = &video_mux_subdev_video_ops,
};
+static int video_mux_parse_endpoint(struct device *dev,
+ struct v4l2_fwnode_endpoint *vep,
+ struct v4l2_async_subdev *asd)
+{
+ /*
+ * it's not an error if remote is missing on a video-mux
+ * input port, return -ENOTCONN to skip this endpoint with
+ * no error.
+ */
+ return fwnode_device_is_available(asd->match.fwnode) ? 0 : -ENOTCONN;
+}
+
+static int video_mux_async_register(struct video_mux *vmux,
+ unsigned int num_pads)
+{
+ unsigned int i, *ports;
+ int ret;
+
+ ports = kcalloc(num_pads - 1, sizeof(*ports), GFP_KERNEL);
+ if (!ports)
+ return -ENOMEM;
+ for (i = 0; i < num_pads - 1; i++)
+ ports[i] = i;
+
+ ret = v4l2_async_register_fwnode_subdev(
+ &vmux->subdev, sizeof(struct v4l2_async_subdev),
+ ports, num_pads - 1, video_mux_parse_endpoint);
+
+ kfree(ports);
+ return ret;
+}
+
static int video_mux_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
@@ -258,7 +292,7 @@ static int video_mux_probe(struct platform_device *pdev)
vmux->subdev.entity.ops = &video_mux_ops;
- return v4l2_async_register_subdev(&vmux->subdev);
+ return video_mux_async_register(vmux, num_pads);
}
static int video_mux_remove(struct platform_device *pdev)
--
2.7.4
