On Sat, Apr 25, 2020 at 07:26:46PM -0700, Jonathan Bakker wrote:
> On some devices, there may be multiple camera sensors attached
> to the same port. Make sure we probe all of them, not just the
> first one.
>
> Signed-off-by: Jonathan Bakker <xc-racer2@xxxxxxx>
> ---
> drivers/media/platform/exynos4-is/media-dev.c | 32 ++++++++++++-------
> 1 file changed, 21 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/media/platform/exynos4-is/media-dev.c b/drivers/media/platform/exynos4-is/media-dev.c
> index b38445219c72..a87ebd7913be 100644
> --- a/drivers/media/platform/exynos4-is/media-dev.c
> +++ b/drivers/media/platform/exynos4-is/media-dev.c
> @@ -397,25 +397,28 @@ static void fimc_md_pipelines_free(struct fimc_md *fmd)
> /* Parse port node and register as a sub-device any sensor specified there. */
> static int fimc_md_parse_port_node(struct fimc_md *fmd,
> struct device_node *port,
> - unsigned int index)
> + unsigned int *index)
> {
> - struct fimc_source_info *pd = &fmd->sensor[index].pdata;
> + struct fimc_source_info *pd;
> struct device_node *rem, *ep, *np;
> - struct v4l2_fwnode_endpoint endpoint = { .bus_type = 0 };
> + struct v4l2_fwnode_endpoint endpoint;
> int ret;
>
> - /* Assume here a port node can have only one endpoint node. */
> ep = of_get_next_child(port, NULL);
> if (!ep)
> return 0;
>
> +parse_sensor:
> + pd = &fmd->sensor[*index].pdata;
> + endpoint.bus_type = 0;
> +
> ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &endpoint);
> if (ret) {
> of_node_put(ep);
> return ret;
> }
>
> - if (WARN_ON(endpoint.base.port == 0) || index >= FIMC_MAX_SENSORS) {
> + if (WARN_ON(endpoint.base.port == 0) || *index >= FIMC_MAX_SENSORS) {
> of_node_put(ep);
> return -EINVAL;
> }
> @@ -462,16 +465,16 @@ static int fimc_md_parse_port_node(struct fimc_md *fmd,
> pd->fimc_bus_type = pd->sensor_bus_type;
> of_node_put(np);
>
> - if (WARN_ON(index >= ARRAY_SIZE(fmd->sensor))) {
> + if (WARN_ON(*index >= ARRAY_SIZE(fmd->sensor))) {
> of_node_put(rem);
> return -EINVAL;
> }
>
> - fmd->sensor[index].asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
> - fmd->sensor[index].asd.match.fwnode = of_fwnode_handle(rem);
> + fmd->sensor[*index].asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
> + fmd->sensor[*index].asd.match.fwnode = of_fwnode_handle(rem);
>
> ret = v4l2_async_notifier_add_subdev(&fmd->subdev_notifier,
> - &fmd->sensor[index].asd);
> + &fmd->sensor[*index].asd);
> if (ret) {
> of_node_put(rem);
> return ret;
> @@ -479,6 +482,13 @@ static int fimc_md_parse_port_node(struct fimc_md *fmd,
>
> fmd->num_sensors++;
>
> + /* Check for additional sensors on same port */
> + ep = of_get_next_child(port, ep);
> + if (ep) {
> + (*index)++;
Do we need this index argument at all? I can see that we already have
fmd->num_sensors and we increment it every time we discover a sensor.
Perhaps we could just use it instead?
> + goto parse_sensor;
As we know, goto in principle isn't the best coding pattern. There is a
number of exceptions where it is welcome, e.g. error handling, but
reimplementing a loop using goto is not very nice.
Instead, could you separate the code that probes one sensor into
fimc_md_parse_one_endpoint() and in this one simply iterate over all child
nodes of the port using for_each_child_of_node()?
Best regards,
Tomasz
