[PATCH v5 08/17] media: imx: csi: Register a subdev notifier

From: Steve Longerbeam
Date: Fri Jun 29 2018 - 14:53:01 EST


Parse neighbor remote devices on the CSI port, and add them to a subdev
notifier, by calling v4l2_async_notifier_parse_fwnode_endpoints_by_port()
using the CSI's port id. And register the subdev notifier for the CSI.

Signed-off-by: Steve Longerbeam <steve_longerbeam@xxxxxxxxxx>
---
Changes since v4:
- none
Changes since v3:
- v4l2_async_register_fwnode_subdev() no longer supports parsing
port sub-devices, so call
v4l2_async_notifier_parse_fwnode_endpoints_by_port() directly.
---
drivers/staging/media/imx/imx-media-csi.c | 55 ++++++++++++++++++++++++++++++-
1 file changed, 54 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
index 06af76d..d5cc4e9 100644
--- a/drivers/staging/media/imx/imx-media-csi.c
+++ b/drivers/staging/media/imx/imx-media-csi.c
@@ -1740,6 +1740,59 @@ static const struct v4l2_subdev_internal_ops csi_internal_ops = {
.unregistered = csi_unregistered,
};

+static int imx_csi_parse_endpoint(struct device *dev,
+ struct v4l2_fwnode_endpoint *vep,
+ struct v4l2_async_subdev *asd)
+{
+ return fwnode_device_is_available(asd->match.fwnode) ? 0 : -EINVAL;
+}
+
+static int imx_csi_async_register(struct csi_priv *priv)
+{
+ struct v4l2_async_notifier *notifier;
+ struct fwnode_handle *fwnode;
+ unsigned int port;
+ int ret;
+
+ notifier = kzalloc(sizeof(*notifier), GFP_KERNEL);
+ if (!notifier)
+ return -ENOMEM;
+
+ fwnode = dev_fwnode(priv->dev);
+
+ /* get this CSI's port id */
+ ret = fwnode_property_read_u32(fwnode, "reg", &port);
+ if (ret < 0)
+ goto out_free;
+
+ ret = v4l2_async_notifier_parse_fwnode_endpoints_by_port(
+ priv->dev->parent, notifier, sizeof(struct v4l2_async_subdev),
+ port, imx_csi_parse_endpoint);
+ if (ret < 0)
+ goto out_cleanup;
+
+ ret = v4l2_async_subdev_notifier_register(&priv->sd, notifier);
+ if (ret < 0)
+ goto out_cleanup;
+
+ ret = v4l2_async_register_subdev(&priv->sd);
+ if (ret < 0)
+ goto out_unregister;
+
+ priv->sd.subdev_notifier = notifier;
+
+ return 0;
+
+out_unregister:
+ v4l2_async_notifier_unregister(notifier);
+out_cleanup:
+ v4l2_async_notifier_cleanup(notifier);
+out_free:
+ kfree(notifier);
+
+ return ret;
+}
+
static int imx_csi_probe(struct platform_device *pdev)
{
struct ipu_client_platformdata *pdata;
@@ -1809,7 +1862,7 @@ static int imx_csi_probe(struct platform_device *pdev)
goto free;
}

- ret = v4l2_async_register_subdev(&priv->sd);
+ ret = imx_csi_async_register(priv);
if (ret)
goto free;

--
2.7.4