wpan-phy: add wpan-phy iteration functions

Add API to iterate over the wpan-phy instances.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>

include/net/wpan-phy.h

@@ -48,6 +48,8 @@ struct wpan_phy *wpan_phy_alloc(size_t priv_size);
 int wpan_phy_register(struct device *parent, struct wpan_phy *phy);
 void wpan_phy_unregister(struct wpan_phy *phy);
 void wpan_phy_free(struct wpan_phy *phy);
+/* Same semantics as for class_for_each_device */
+int wpan_phy_for_each(int (*fn)(struct wpan_phy *phy, void *data), void *data);
 
 static inline void *wpan_phy_priv(struct wpan_phy *phy)
 {

net/ieee802154/wpan-class.c

@@ -91,6 +91,31 @@ struct wpan_phy *wpan_phy_find(const char *str)
 }
 EXPORT_SYMBOL(wpan_phy_find);
 
+struct wpan_phy_iter_data {
+	int (*fn)(struct wpan_phy *phy, void *data);
+	void *data;
+};
+
+static int wpan_phy_iter(struct device *dev, void *_data)
+{
+	struct wpan_phy_iter_data *wpid = _data;
+	struct wpan_phy *phy = container_of(dev, struct wpan_phy, dev);
+	return wpid->fn(phy, wpid->data);
+}
+
+int wpan_phy_for_each(int (*fn)(struct wpan_phy *phy, void *data),
+		void *data)
+{
+	struct wpan_phy_iter_data wpid = {
+		.fn = fn,
+		.data = data,
+	};
+
+	return class_for_each_device(&wpan_phy_class, NULL,
+			&wpid, wpan_phy_iter);
+}
+EXPORT_SYMBOL(wpan_phy_for_each);
+
 static int wpan_phy_idx_valid(int idx)
 {
 	return idx >= 0;