usb: add devicetree helpers for determining dr_mode and phy_type

This adds two little devicetree helper functions for determining the
dr_mode (host, peripheral, otg) and phy_type (utmi, ulpi,...) from
the devicetree.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/phy/Makefile

@@ -5,6 +5,7 @@
 ccflags-$(CONFIG_USB_DEBUG) := -DDEBUG
 
 obj-$(CONFIG_USB_PHY)			+= phy.o
+obj-$(CONFIG_OF)			+= of.o
 
 # transceiver drivers, keep the list sorted
 

drivers/usb/phy/of.c

@@ -0,0 +1,47 @@
+/*
+ * USB of helper code
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/usb/of.h>
+#include <linux/usb/otg.h>
+
+static const char *const usbphy_modes[] = {
+	[USBPHY_INTERFACE_MODE_UNKNOWN]	= "",
+	[USBPHY_INTERFACE_MODE_UTMI]	= "utmi",
+	[USBPHY_INTERFACE_MODE_UTMIW]	= "utmi_wide",
+	[USBPHY_INTERFACE_MODE_ULPI]	= "ulpi",
+	[USBPHY_INTERFACE_MODE_SERIAL]	= "serial",
+	[USBPHY_INTERFACE_MODE_HSIC]	= "hsic",
+};
+
+/**
+ * of_usb_get_phy_mode - Get phy mode for given device_node
+ * @np:	Pointer to the given device_node
+ *
+ * The function gets phy interface string from property 'phy_type',
+ * and returns the correspondig enum usb_phy_interface
+ */
+enum usb_phy_interface of_usb_get_phy_mode(struct device_node *np)
+{
+	const char *phy_type;
+	int err, i;
+
+	err = of_property_read_string(np, "phy_type", &phy_type);
+	if (err < 0)
+		return USBPHY_INTERFACE_MODE_UNKNOWN;
+
+	for (i = 0; i < ARRAY_SIZE(usbphy_modes); i++)
+		if (!strcmp(phy_type, usbphy_modes[i]))
+			return i;
+
+	return USBPHY_INTERFACE_MODE_UNKNOWN;
+}
+EXPORT_SYMBOL_GPL(of_usb_get_phy_mode);

drivers/usb/usb-common.c

@@ -13,7 +13,9 @@
 
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/usb/ch9.h>
+#include <linux/usb/of.h>
 #include <linux/usb/otg.h>
 
 const char *usb_otg_state_string(enum usb_otg_state state)
@@ -79,4 +81,37 @@ const char *usb_state_string(enum usb_device_state state)
 }
 EXPORT_SYMBOL_GPL(usb_state_string);
 
+#ifdef CONFIG_OF
+static const char *const usb_dr_modes[] = {
+	[USB_DR_MODE_UNKNOWN]		= "",
+	[USB_DR_MODE_HOST]		= "host",
+	[USB_DR_MODE_PERIPHERAL]	= "peripheral",
+	[USB_DR_MODE_OTG]		= "otg",
+};
+
+/**
+ * of_usb_get_dr_mode - Get dual role mode for given device_node
+ * @np:	Pointer to the given device_node
+ *
+ * The function gets phy interface string from property 'dr_mode',
+ * and returns the correspondig enum usb_dr_mode
+ */
+enum usb_dr_mode of_usb_get_dr_mode(struct device_node *np)
+{
+	const char *dr_mode;
+	int err, i;
+
+	err = of_property_read_string(np, "dr_mode", &dr_mode);
+	if (err < 0)
+		return USB_DR_MODE_UNKNOWN;
+
+	for (i = 0; i < ARRAY_SIZE(usb_dr_modes); i++)
+		if (!strcmp(dr_mode, usb_dr_modes[i]))
+			return i;
+
+	return USB_DR_MODE_UNKNOWN;
+}
+EXPORT_SYMBOL_GPL(of_usb_get_dr_mode);
+#endif
+
 MODULE_LICENSE("GPL");

include/linux/usb/of.h

@@ -0,0 +1,28 @@
+/*
+ * OF helpers for usb devices.
+ *
+ * This file is released under the GPLv2
+ */
+
+#ifndef __LINUX_USB_OF_H
+#define __LINUX_USB_OF_H
+
+#include <linux/usb/otg.h>
+#include <linux/usb/phy.h>
+
+#ifdef CONFIG_OF
+enum usb_phy_interface of_usb_get_phy_mode(struct device_node *np);
+enum usb_dr_mode of_usb_get_dr_mode(struct device_node *np);
+#else
+static inline enum usb_phy_interface of_usb_get_phy_mode(struct device_node *np)
+{
+	return USBPHY_INTERFACE_MODE_UNKNOWN;
+}
+
+static inline enum usb_dr_mode of_usb_get_dr_mode(struct device_node *np)
+{
+	return USB_DR_MODE_UNKNOWN;
+}
+#endif
+
+#endif /* __LINUX_USB_OF_H */

include/linux/usb/otg.h

@@ -92,4 +92,11 @@ otg_start_srp(struct usb_otg *otg)
 /* for OTG controller drivers (and maybe other stuff) */
 extern int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num);
 
+enum usb_dr_mode {
+	USB_DR_MODE_UNKNOWN,
+	USB_DR_MODE_HOST,
+	USB_DR_MODE_PERIPHERAL,
+	USB_DR_MODE_OTG,
+};
+
 #endif /* __LINUX_USB_OTG_H */

include/linux/usb/phy.h

@@ -12,6 +12,15 @@
 #include <linux/notifier.h>
 #include <linux/usb.h>
 
+enum usb_phy_interface {
+	USBPHY_INTERFACE_MODE_UNKNOWN,
+	USBPHY_INTERFACE_MODE_UTMI,
+	USBPHY_INTERFACE_MODE_UTMIW,
+	USBPHY_INTERFACE_MODE_ULPI,
+	USBPHY_INTERFACE_MODE_SERIAL,
+	USBPHY_INTERFACE_MODE_HSIC,
+};
+
 enum usb_phy_events {
 	USB_EVENT_NONE,         /* no events or cable disconnected */
 	USB_EVENT_VBUS,         /* vbus valid event */