Hi Laurent,
On Tue, Sep 19, 2017 at 03:19:59PM +0300, Laurent Pinchart wrote:
> Hi Sakari,
>
> Thank you for the patch.
>
> On Friday, 15 September 2017 17:17:16 EEST Sakari Ailus wrote:
> > Add function 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.
> >
> > Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> > ---
> > drivers/media/v4l2-core/v4l2-fwnode.c | 69 ++++++++++++++++++++++++++++++++
> > 1 file changed, 69 insertions(+)
> >
> > diff --git a/drivers/media/v4l2-core/v4l2-fwnode.c
> > b/drivers/media/v4l2-core/v4l2-fwnode.c index 44ee35f6aad5..65e84ea1cc35
> > 100644
> > --- a/drivers/media/v4l2-core/v4l2-fwnode.c
> > +++ b/drivers/media/v4l2-core/v4l2-fwnode.c
> > @@ -498,6 +498,75 @@ int v4l2_async_notifier_parse_fwnode_endpoints_by_port(
> > }
> > EXPORT_SYMBOL_GPL(v4l2_async_notifier_parse_fwnode_endpoints_by_port);
> >
> > +/*
> > + * v4l2_fwnode_reference_parse - parse references for async sub-devices
> > + * @dev: the device node the properties of which are parsed for references
> > + * @notifier: the async notifier where the async subdevs will be added
> > + * @prop: the name of the property
> > + *
> > + * Return: 0 on success
> > + * -ENOENT if no entries were found
> > + * -ENOMEM if memory allocation failed
> > + * -EINVAL if property parsing failed
> > + */
> > +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;
> > + int ret;
> > +
> > + for (index = 0;
> > + !(ret = fwnode_property_get_reference_args(
> > + dev_fwnode(dev), prop, NULL, 0, index, &args));
> > + index++)
> > + fwnode_handle_put(args.fwnode);
>
> This seems to indicate that the fwnode API is missing a function to count the
> number of references in a property. Should that be fixed ?
I can send a patch adding that.
OF has one available but it's only for cases where the number of integer
arguments isn't fixed.
>
> The rest looks OK to me.
>
> > + if (!index)
> > + return -ENOENT;
> > +
> > + /*
> > + * Note that right now both -ENODATA and -ENOENT may signal
> > + * out-of-bounds access. Return the error in cases other than that.
> > + */
> > + if (ret != -ENOENT && ret != -ENODATA)
> > + return ret;
> > +
> > + ret = v4l2_async_notifier_realloc(notifier,
> > + notifier->num_subdevs + index);
> > + if (ret)
> > + return ret;
> > +
> > + for (index = 0; !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++;
> > + }
> > +
> > + 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,
>
> Laurent Pinchart
>
--
Sakari Ailus
sakari.ailus@xxxxxxxxxxxxxxx
