usb: otg: add an api to bind the usb controller and phy

In order to support platforms which has multiple PHY's (of same type) and
which has multiple USB controllers, a new design is adopted wherin the binding
information (between the PHY and the USB controller) should be passed to the
PHY library from platform specific file (board file).
So added a new API to pass the binding information.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/otg/otg.c

@@ -18,6 +18,7 @@
 #include <linux/usb/otg.h>
 
 static LIST_HEAD(phy_list);
+static LIST_HEAD(phy_bind_list);
 static DEFINE_SPINLOCK(phy_lock);
 
 static struct usb_phy *__usb_find_phy(struct list_head *list,
@@ -201,6 +202,42 @@ void usb_remove_phy(struct usb_phy *x)
 }
 EXPORT_SYMBOL(usb_remove_phy);
 
+/**
+ * usb_bind_phy - bind the phy and the controller that uses the phy
+ * @dev_name: the device name of the device that will bind to the phy
+ * @index: index to specify the port number
+ * @phy_dev_name: the device name of the phy
+ *
+ * Fills the phy_bind structure with the dev_name and phy_dev_name. This will
+ * be used when the phy driver registers the phy and when the controller
+ * requests this phy.
+ *
+ * To be used by platform specific initialization code.
+ */
+int __init usb_bind_phy(const char *dev_name, u8 index,
+				const char *phy_dev_name)
+{
+	struct usb_phy_bind *phy_bind;
+	unsigned long flags;
+
+	phy_bind = kzalloc(sizeof(*phy_bind), GFP_KERNEL);
+	if (!phy_bind) {
+		pr_err("phy_bind(): No memory for phy_bind");
+		return -ENOMEM;
+	}
+
+	phy_bind->dev_name = dev_name;
+	phy_bind->phy_dev_name = phy_dev_name;
+	phy_bind->index = index;
+
+	spin_lock_irqsave(&phy_lock, flags);
+	list_add_tail(&phy_bind->list, &phy_bind_list);
+	spin_unlock_irqrestore(&phy_lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(usb_bind_phy);
+
 const char *otg_state_string(enum usb_otg_state state)
 {
 	switch (state) {

include/linux/usb/phy.h

@@ -106,6 +106,21 @@ struct usb_phy {
 			enum usb_device_speed speed);
 };
 
+/**
+ * struct usb_phy_bind - represent the binding for the phy
+ * @dev_name: the device name of the device that will bind to the phy
+ * @phy_dev_name: the device name of the phy
+ * @index: used if a single controller uses multiple phys
+ * @phy: reference to the phy
+ * @list: to maintain a linked list of the binding information
+ */
+struct usb_phy_bind {
+	const char	*dev_name;
+	const char	*phy_dev_name;
+	u8		index;
+	struct usb_phy	*phy;
+	struct list_head list;
+};
 
 /* for board-specific init logic */
 extern int usb_add_phy(struct usb_phy *, enum usb_phy_type type);
@@ -151,6 +166,8 @@ extern struct usb_phy *devm_usb_get_phy(struct device *dev,
 	enum usb_phy_type type);
 extern void usb_put_phy(struct usb_phy *);
 extern void devm_usb_put_phy(struct device *dev, struct usb_phy *x);
+extern int usb_bind_phy(const char *dev_name, u8 index,
+				const char *phy_dev_name);
 #else
 static inline struct usb_phy *usb_get_phy(enum usb_phy_type type)
 {
@@ -171,6 +188,11 @@ static inline void devm_usb_put_phy(struct device *dev, struct usb_phy *x)
 {
 }
 
+static inline int usb_bind_phy(const char *dev_name, u8 index,
+				const char *phy_dev_name)
+{
+	return -EOPNOTSUPP;
+}
 #endif
 
 static inline int