On 09/12/2017 03:41 PM, Sakari Ailus wrote: > Add function v4l2_fwnode_reference_count() for counting external ???? There is no function v4l2_fwnode_reference_count()?! > 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. You forgot to remove this outdated paragraph. > > 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..a32473f95be1 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); > + > + if (!index) > + return -ENOENT; > + > + /* > + * To-do: handle -ENODATA when "device property: Align return > + * codes of acpi_fwnode_get_reference_with_args" is merged. > + */ > + if (ret != -ENOENT && ret != -ENODATA) So while that patch referenced in the To-do above is not merged yet, what does fwnode_property_get_reference_args return? ENOENT or ENODATA? Or ENOENT now and ENODATA later? Or vice versa? I can't tell based on that information whether this code is correct or not. The comment needs to explain this a bit better. > + 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, Hans