Hi Tomasz,
On 2020-07-07 11:36 a.m., Tomasz Figa wrote:
> 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()?
>
That definitely looks doable, thanks for the suggestion. I'll work on implementing
and testing this. It should then also be possible to remove the index hack as well.
> Best regards,
> Tomasz
>
Thanks,
Jonathan
