Hi Eugen,
On Tue, Nov 23, 2021 at 01:15:21PM +0200, Eugen Hristev wrote:
> Implement fwnode parsing at probe time.
> Check if the bus and number of lanes are supported.
>
> Signed-off-by: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
> ---
> drivers/media/i2c/imx274.c | 40 ++++++++++++++++++++++++++++++++++++++
> 1 file changed, 40 insertions(+)
>
> diff --git a/drivers/media/i2c/imx274.c b/drivers/media/i2c/imx274.c
> index e31f006b10d9..774912f44efe 100644
> --- a/drivers/media/i2c/imx274.c
> +++ b/drivers/media/i2c/imx274.c
> @@ -27,6 +27,7 @@
>
> #include <media/v4l2-ctrls.h>
> #include <media/v4l2-device.h>
> +#include <media/v4l2-fwnode.h>
> #include <media/v4l2-subdev.h>
>
> /*
> @@ -1957,6 +1958,41 @@ static const struct i2c_device_id imx274_id[] = {
> };
> MODULE_DEVICE_TABLE(i2c, imx274_id);
>
> +static int imx274_fwnode_parse(struct device *dev)
> +{
> + struct fwnode_handle *endpoint;
> + /* Only CSI2 is supported */
> + struct v4l2_fwnode_endpoint ep = {
> + .bus_type = V4L2_MBUS_CSI2_DPHY
> + };
> + int ret;
> +
> + endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(dev), NULL);
> + if (!endpoint) {
> + dev_err(dev, "Endpoint node not found\n");
> + return -EINVAL;
> + }
> +
> + ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &ep);
This allocates memory for the link frequencies. It needs to be released at
some point.
You could also use v4l1_fwnode_endpoint_parse() as the driver doesn't seem
to use link frequencies (albeit it probably should, but that's another
discussion).
> + fwnode_handle_put(endpoint);
> + if (ret == -ENXIO) {
> + dev_err(dev, "Unsupported bus type, should be CSI2\n");
> + return ret;
> + } else if (ret) {
> + dev_err(dev, "Parsing endpoint node failed %d\n", ret);
> + return ret;
> + }
> +
> + /* Check number of data lanes, only 4 lanes supported */
> + if (ep.bus.mipi_csi2.num_data_lanes != 4) {
> + dev_err(dev, "Invalid data lanes: %d\n",
> + ep.bus.mipi_csi2.num_data_lanes);
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> static int imx274_probe(struct i2c_client *client)
> {
> struct v4l2_subdev *sd;
> @@ -1971,6 +2007,10 @@ static int imx274_probe(struct i2c_client *client)
>
> mutex_init(&imx274->lock);
>
> + ret = imx274_fwnode_parse(dev);
> + if (ret)
> + return ret;
> +
> imx274->inck = devm_clk_get_optional(dev, "inck");
> if (IS_ERR(imx274->inck))
> return PTR_ERR(imx274->inck);
--
Kind regards,
Sakari Ailus
