On 09/11/2017 10:00 AM, Sakari Ailus wrote:
> Add function v4l2_fwnode_reference_count() for counting external
> references and v4l2_fwnode_reference_parse() for parsing them as async
> sub-devices.
>
> This can be done on e.g. flash or lens async sub-devices that are not part
> of but are associated with a sensor.
>
> struct v4l2_async_notifier.max_subdevs field is added to contain the
> maximum number of sub-devices in a notifier to reflect the memory
> allocated for the subdevs array.
This paragraph appears to be out-of-date.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> ---
> drivers/media/v4l2-core/v4l2-fwnode.c | 47 +++++++++++++++++++++++++++++++++++
> 1 file changed, 47 insertions(+)
>
> diff --git a/drivers/media/v4l2-core/v4l2-fwnode.c b/drivers/media/v4l2-core/v4l2-fwnode.c
> index d978f2d714ca..4821c4989119 100644
> --- a/drivers/media/v4l2-core/v4l2-fwnode.c
> +++ b/drivers/media/v4l2-core/v4l2-fwnode.c
> @@ -449,6 +449,53 @@ int v4l2_async_notifier_parse_fwnode_endpoints(
> }
> EXPORT_SYMBOL_GPL(v4l2_async_notifier_parse_fwnode_endpoints);
>
> +static int v4l2_fwnode_reference_parse(
> + struct device *dev, struct v4l2_async_notifier *notifier,
> + const char *prop)
> +{
> + struct fwnode_reference_args args;
> + unsigned int index = 0;
> + int ret;
> +
> + for (; !fwnode_property_get_reference_args(
> + dev_fwnode(dev), prop, NULL, 0, index, &args); index++)
> + fwnode_handle_put(args.fwnode);
> +
If nothing is found (i.e. index == 0), shouldn't you just return here?
> + ret = v4l2_async_notifier_realloc(notifier,
> + notifier->num_subdevs + index);
> + if (ret)
> + return -ENOMEM;
> +
> + for (ret = -ENOENT, index = 0;
There is no reason for the 'ret = -ENOENT' to be in the for(), just set it before
the 'for' statement.
> + !fwnode_property_get_reference_args(
> + dev_fwnode(dev), prop, NULL, 0, index, &args);
> + index++) {
> + struct v4l2_async_subdev *asd;
> +
> + if (WARN_ON(notifier->num_subdevs >= notifier->max_subdevs)) {
> + ret = -EINVAL;
> + goto error;
> + }
> +
> + asd = kzalloc(sizeof(*asd), GFP_KERNEL);
> + if (!asd) {
> + ret = -ENOMEM;
> + goto error;
> + }
> +
> + notifier->subdevs[notifier->num_subdevs] = asd;
> + asd->match.fwnode.fwnode = args.fwnode;
> + asd->match_type = V4L2_ASYNC_MATCH_FWNODE;
> + notifier->num_subdevs++;
> + }
If the loop doesn't find anything, then it still returns 0, not -ENOENT.
So why set ret to ENOENT? Something weird going on here.
I think you should also add a comment explaining this function.
> +
> + return 0;
> +
> +error:
> + fwnode_handle_put(args.fwnode);
> + return ret;
> +}
> +
> MODULE_LICENSE("GPL");
> MODULE_AUTHOR("Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>");
> MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx>");
>
Regards,
Hans
