phy: Add set_mode callback

The initial use for this is for PHYs that have a mode related to USB OTG.
There are several SoCs (e.g. TI OMAP and DA8xx) that have a mode setting
in the USB PHY to override OTG VBUS and ID signals.

Of course, the enum can be expaned in the future to include modes for
other types of PHYs as well.
Suggested-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: David Lechner <david@lechnology.com>

drivers/phy/phy-core.c

@@ -342,6 +342,21 @@ int phy_power_off(struct phy *phy)
 }
 EXPORT_SYMBOL_GPL(phy_power_off);
 
+int phy_set_mode(struct phy *phy, enum phy_mode mode)
+{
+	int ret;
+
+	if (!phy || !phy->ops->set_mode)
+		return 0;
+
+	mutex_lock(&phy->mutex);
+	ret = phy->ops->set_mode(phy, mode);
+	mutex_unlock(&phy->mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(phy_set_mode);
+
 /**
  * _of_phy_get() - lookup and obtain a reference to a phy by phandle
  * @np: device_node for which to get the phy

include/linux/phy/phy.h

@@ -22,12 +22,20 @@
 
 struct phy;
 
+enum phy_mode {
+	PHY_MODE_INVALID,
+	PHY_MODE_USB_HOST,
+	PHY_MODE_USB_DEVICE,
+	PHY_MODE_USB_OTG,
+};
+
 /**
  * struct phy_ops - set of function pointers for performing phy operations
  * @init: operation to be performed for initializing phy
  * @exit: operation to be performed while exiting
  * @power_on: powering on the phy
  * @power_off: powering off the phy
+ * @set_mode: set the mode of the phy
  * @owner: the module owner containing the ops
  */
 struct phy_ops {
@@ -35,6 +43,7 @@ struct phy_ops {
 	int	(*exit)(struct phy *phy);
 	int	(*power_on)(struct phy *phy);
 	int	(*power_off)(struct phy *phy);
+	int	(*set_mode)(struct phy *phy, enum phy_mode mode);
 	struct module *owner;
 };
 
@@ -126,6 +135,7 @@ int phy_init(struct phy *phy);
 int phy_exit(struct phy *phy);
 int phy_power_on(struct phy *phy);
 int phy_power_off(struct phy *phy);
+int phy_set_mode(struct phy *phy, enum phy_mode mode);
 static inline int phy_get_bus_width(struct phy *phy)
 {
 	return phy->attrs.bus_width;
@@ -233,6 +243,13 @@ static inline int phy_power_off(struct phy *phy)
 	return -ENOSYS;
 }
 
+static inline int phy_set_mode(struct phy *phy, enum phy_mode mode)
+{
+	if (!phy)
+		return 0;
+	return -ENOSYS;
+}
+
 static inline int phy_get_bus_width(struct phy *phy)
 {
 	return -ENOSYS;