From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Subject: Re: [PATCH v13 17/25] v4l: fwnode: Add a helper function for parsing generic references Date: Tue, 19 Sep 2017 15:19:59 +0300 Message-ID: <2639286.bLnehYdF9o@avalon> References: <20170915141724.23124-1-sakari.ailus@linux.intel.com> <20170915141724.23124-18-sakari.ailus@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: <20170915141724.23124-18-sakari.ailus-VuQAYsv1563Yd54FQh9/CA@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sakari Ailus Cc: linux-media-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, niklas.soderlund-1zkq55x86MTxsAP9Fp7wbw@public.gmane.org, maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org, robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, hverkuil-qWit8jRvyhVmR6Xm/wNWPw@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, pavel-+ZI9xUNit7I@public.gmane.org, sre-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org List-Id: devicetree@vger.kernel.org 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 > --- > 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 ? 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 "); > MODULE_AUTHOR("Sylwester Nawrocki "); -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html