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.
Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
---
drivers/media/v4l2-core/v4l2-fwnode.c | 81 +++++++++++++++++++++++++++++++++++
include/media/v4l2-fwnode.h | 28 ++++++++++++
2 files changed, 109 insertions(+)
diff --git a/drivers/media/v4l2-core/v4l2-fwnode.c b/drivers/media/v4l2-core/v4l2-fwnode.c
index f8c7a9bc6a58..24f8020caf28 100644
--- a/drivers/media/v4l2-core/v4l2-fwnode.c
+++ b/drivers/media/v4l2-core/v4l2-fwnode.c
@@ -449,6 +449,87 @@ int v4l2_async_notifier_parse_fwnode_endpoints(
}
EXPORT_SYMBOL_GPL(v4l2_async_notifier_parse_fwnode_endpoints);
+static void v4l2_fwnode_print_args(struct fwnode_reference_args *args)
+{
+ unsigned int i;
+
+ for (i = 0; i < args->nargs; i++) {
+ pr_cont(" %u", args->args[i]);
+ if (i + 1 < args->nargs)
+ pr_cont(",");
+ }
+}
+
+int v4l2_fwnode_reference_parse(
+ struct device *dev, struct v4l2_async_notifier *notifier,
+ const char *prop, const char *nargs_prop, unsigned int nargs,
+ size_t asd_struct_size,
+ int (*parse_single)(struct device *dev,
+ struct fwnode_reference_args *args,
+ struct v4l2_async_subdev *asd))
+{
+ struct fwnode_reference_args args;
+ unsigned int index = 0;
+ int ret = -ENOENT;
+
+ if (asd_struct_size < sizeof(struct v4l2_async_subdev))
+ return -EINVAL;
+
+ for (; !fwnode_property_get_reference_args(
+ dev_fwnode(dev), prop, nargs_prop, nargs,
+ index, &args); index++)
+ fwnode_handle_put(args.fwnode);
+
+ ret = v4l2_async_notifier_realloc(notifier,
+ notifier->num_subdevs + index);
+ if (ret)
+ return -ENOMEM;
+
+ for (ret = -ENOENT, index = 0; !fwnode_property_get_reference_args(
+ dev_fwnode(dev), prop, nargs_prop, nargs,
+ index, &args); index++) {
+ struct v4l2_async_subdev *asd;
+
+ if (WARN_ON(notifier->num_subdevs >= notifier->max_subdevs))
+ break;
+
+ asd = kzalloc(asd_struct_size, GFP_KERNEL);
+ if (!asd) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ ret = parse_single ? parse_single(dev, &args, asd) : 0;
+ if (ret == -ENOTCONN) {
+ dev_dbg(dev,
+ "ignoring reference prop \"%s\", nargs_prop \"%s\", nargs %u, index %u",
+ prop, nargs_prop, nargs, index);
+ v4l2_fwnode_print_args(&args);
+ pr_cont("\n");
+ continue;
+ } else if (ret < 0) {
+ dev_warn(dev,
+ "driver could not parse reference prop \"%s\", nargs_prop \"%s\", nargs %u, index %u",
+ prop, nargs_prop, nargs, index);
+ v4l2_fwnode_print_args(&args);
+ pr_cont("\n");
+ 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;
+}
+EXPORT_SYMBOL_GPL(v4l2_fwnode_reference_parse);
+
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>");
MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx>");
diff --git a/include/media/v4l2-fwnode.h b/include/media/v4l2-fwnode.h
index 6d125f26ec84..52f528162818 100644
--- a/include/media/v4l2-fwnode.h
+++ b/include/media/v4l2-fwnode.h
@@ -254,4 +254,32 @@ int v4l2_async_notifier_parse_fwnode_endpoints(
struct v4l2_fwnode_endpoint *vep,
struct v4l2_async_subdev *asd));
+/**
+ * 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
+ * @nargs_prop: the name of the property in the remote node that specifies the
+ * number of integer arguments (may be NULL, in that case nargs
+ * will be used).
+ * @nargs: the number of integer arguments after the reference
+ * @asd_struct_size: the size of the driver's async sub-device struct, including
+ * @struct v4l2_async_subdev
+ * @parse_single: Driver's callback function for parsing a reference. Optional.
+ * Return: 0 on success
+ * %-ENOTCONN if the reference is to be skipped but this
+ * should not be considered as an error
+ *
+ * Return: 0 on success
+ * -ENOMEM if memory allocation failed
+ * -EINVAL if property parsing failed
+ */
+int v4l2_fwnode_reference_parse(
+ struct device *dev, struct v4l2_async_notifier *notifier,
+ const char *prop, const char *nargs_prop, unsigned int nargs,
+ size_t asd_struct_size,
+ int (*parse_single)(struct device *dev,
+ struct fwnode_reference_args *args,
+ struct v4l2_async_subdev *asd));
+
#endif /* _V4L2_FWNODE_H */
--
2.11.0
