1 files changed, 102 insertions, 0 deletions
diff --git a/drivers/usb/otg/otg.c b/drivers/usb/otg/otg.c
new file mode 100644
index 00000000..801e597a
--- /dev/null
+++ b/drivers/usb/otg/otg.c
@@ -0,0 +1,102 @@
+/*
+ * otg.c -- USB OTG utility code
+ *
+ * Copyright (C) 2004 Texas Instruments
+ *
+ * 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/export.h>
+#include <linux/device.h>
+
+#include <linux/usb/otg.h>
+
+static struct usb_phy *phy;
+
+/**
+ * usb_get_transceiver - find the (single) USB transceiver
+ *
+ * Returns the transceiver driver, after getting a refcount to it; or
+ * null if there is no such transceiver.  The caller is responsible for
+ * calling usb_put_transceiver() to release that count.
+ *
+ * For use by USB host and peripheral drivers.
+ */
+struct usb_phy *usb_get_transceiver(void)
+{
+	if (phy)
+		get_device(phy->dev);
+	return phy;
+}
+EXPORT_SYMBOL(usb_get_transceiver);
+
+/**
+ * usb_put_transceiver - release the (single) USB transceiver
+ * @x: the transceiver returned by usb_get_transceiver()
+ *
+ * Releases a refcount the caller received from usb_get_transceiver().
+ *
+ * For use by USB host and peripheral drivers.
+ */
+void usb_put_transceiver(struct usb_phy *x)
+{
+	if (x)
+		put_device(x->dev);
+}
+EXPORT_SYMBOL(usb_put_transceiver);
+
+/**
+ * usb_set_transceiver - declare the (single) USB transceiver
+ * @x: the USB transceiver to be used; or NULL
+ *
+ * This call is exclusively for use by transceiver drivers, which
+ * coordinate the activities of drivers for host and peripheral
+ * controllers, and in some cases for VBUS current regulation.
+ */
+int usb_set_transceiver(struct usb_phy *x)
+{
+	if (phy && x)
+		return -EBUSY;
+	phy = x;
+	return 0;
+}
+EXPORT_SYMBOL(usb_set_transceiver);
+
+const char *otg_state_string(enum usb_otg_state state)
+{
+	switch (state) {
+	case OTG_STATE_A_IDLE:
+		return "a_idle";
+	case OTG_STATE_A_WAIT_VRISE:
+		return "a_wait_vrise";
+	case OTG_STATE_A_WAIT_BCON:
+		return "a_wait_bcon";
+	case OTG_STATE_A_HOST:
+		return "a_host";
+	case OTG_STATE_A_SUSPEND:
+		return "a_suspend";
+	case OTG_STATE_A_PERIPHERAL:
+		return "a_peripheral";
+	case OTG_STATE_A_WAIT_VFALL:
+		return "a_wait_vfall";
+	case OTG_STATE_A_VBUS_ERR:
+		return "a_vbus_err";
+	case OTG_STATE_B_IDLE:
+		return "b_idle";
+	case OTG_STATE_B_SRP_INIT:
+		return "b_srp_init";
+	case OTG_STATE_B_PERIPHERAL:
+		return "b_peripheral";
+	case OTG_STATE_B_WAIT_ACON:
+		return "b_wait_acon";
+	case OTG_STATE_B_HOST:
+		return "b_host";
+	default:
+		return "UNDEFINED";
+	}
+}
+EXPORT_SYMBOL(otg_state_string);