Initial import

4 files changed, 592 insertions, 0 deletions

diff --git a/drivers/usb/common/Makefile b/drivers/usb/common/Makefile
new file mode 100644
index 000000000..ca2f8bd0e
--- /dev/null
+++ b/drivers/usb/common/Makefile
@@ -0,0 +1,9 @@
+#
+# Makefile for the usb common parts.
+#
+
+obj-$(CONFIG_USB_COMMON)	  += usb-common.o
+usb-common-y			  += common.o
+usb-common-$(CONFIG_USB_LED_TRIG) += led.o
+
+obj-$(CONFIG_USB_OTG_FSM) += usb-otg-fsm.o
diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c
new file mode 100644
index 000000000..b530fd403
--- /dev/null
+++ b/drivers/usb/common/common.c
@@ -0,0 +1,159 @@
+/*
+ * Provides code common for host and device side USB.
+ *
+ * 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, version 2.
+ *
+ * If either host side (ie. CONFIG_USB=y) or device side USB stack
+ * (ie. CONFIG_USB_GADGET=y) is compiled in the kernel, this module is
+ * compiled-in as well.  Otherwise, if either of the two stacks is
+ * compiled as module, this file is compiled as module as well.
+ */
+
+#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)
+{
+	static const char *const names[] = {
+		[OTG_STATE_A_IDLE] = "a_idle",
+		[OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
+		[OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
+		[OTG_STATE_A_HOST] = "a_host",
+		[OTG_STATE_A_SUSPEND] = "a_suspend",
+		[OTG_STATE_A_PERIPHERAL] = "a_peripheral",
+		[OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
+		[OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
+		[OTG_STATE_B_IDLE] = "b_idle",
+		[OTG_STATE_B_SRP_INIT] = "b_srp_init",
+		[OTG_STATE_B_PERIPHERAL] = "b_peripheral",
+		[OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
+		[OTG_STATE_B_HOST] = "b_host",
+	};
+
+	if (state < 0 || state >= ARRAY_SIZE(names))
+		return "UNDEFINED";
+
+	return names[state];
+}
+EXPORT_SYMBOL_GPL(usb_otg_state_string);
+
+static const char *const speed_names[] = {
+	[USB_SPEED_UNKNOWN] = "UNKNOWN",
+	[USB_SPEED_LOW] = "low-speed",
+	[USB_SPEED_FULL] = "full-speed",
+	[USB_SPEED_HIGH] = "high-speed",
+	[USB_SPEED_WIRELESS] = "wireless",
+	[USB_SPEED_SUPER] = "super-speed",
+};
+
+const char *usb_speed_string(enum usb_device_speed speed)
+{
+	if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
+		speed = USB_SPEED_UNKNOWN;
+	return speed_names[speed];
+}
+EXPORT_SYMBOL_GPL(usb_speed_string);
+
+const char *usb_state_string(enum usb_device_state state)
+{
+	static const char *const names[] = {
+		[USB_STATE_NOTATTACHED] = "not attached",
+		[USB_STATE_ATTACHED] = "attached",
+		[USB_STATE_POWERED] = "powered",
+		[USB_STATE_RECONNECTING] = "reconnecting",
+		[USB_STATE_UNAUTHENTICATED] = "unauthenticated",
+		[USB_STATE_DEFAULT] = "default",
+		[USB_STATE_ADDRESS] = "addressed",
+		[USB_STATE_CONFIGURED] = "configured",
+		[USB_STATE_SUSPENDED] = "suspended",
+	};
+
+	if (state < 0 || state >= ARRAY_SIZE(names))
+		return "UNKNOWN";
+
+	return names[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);
+
+/**
+ * of_usb_get_maximum_speed - Get maximum requested speed for a given USB
+ * controller.
+ * @np: Pointer to the given device_node
+ *
+ * The function gets the maximum speed string from property "maximum-speed",
+ * and returns the corresponding enum usb_device_speed.
+ */
+enum usb_device_speed of_usb_get_maximum_speed(struct device_node *np)
+{
+	const char *maximum_speed;
+	int err;
+	int i;
+
+	err = of_property_read_string(np, "maximum-speed", &maximum_speed);
+	if (err < 0)
+		return USB_SPEED_UNKNOWN;
+
+	for (i = 0; i < ARRAY_SIZE(speed_names); i++)
+		if (strcmp(maximum_speed, speed_names[i]) == 0)
+			return i;
+
+	return USB_SPEED_UNKNOWN;
+}
+EXPORT_SYMBOL_GPL(of_usb_get_maximum_speed);
+
+/**
+ * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
+ * for given targeted hosts (non-PC hosts)
+ * @np: Pointer to the given device_node
+ *
+ * The function gets if the targeted hosts support TPL or not
+ */
+bool of_usb_host_tpl_support(struct device_node *np)
+{
+	if (of_find_property(np, "tpl-support", NULL))
+		return true;
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
+#endif
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/usb/common/led.c b/drivers/usb/common/led.c
new file mode 100644
index 000000000..df23da00a
--- /dev/null
+++ b/drivers/usb/common/led.c
@@ -0,0 +1,57 @@
+/*
+ * LED Triggers for USB Activity
+ *
+ * Copyright 2014 Michal Sojka <sojka@merica.cz>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+#include <linux/usb.h>
+
+#define BLINK_DELAY 30
+
+static unsigned long usb_blink_delay = BLINK_DELAY;
+
+DEFINE_LED_TRIGGER(ledtrig_usb_gadget);
+DEFINE_LED_TRIGGER(ledtrig_usb_host);
+
+void usb_led_activity(enum usb_led_event ev)
+{
+	struct led_trigger *trig = NULL;
+
+	switch (ev) {
+	case USB_LED_EVENT_GADGET:
+		trig = ledtrig_usb_gadget;
+		break;
+	case USB_LED_EVENT_HOST:
+		trig = ledtrig_usb_host;
+		break;
+	}
+	/* led_trigger_blink_oneshot() handles trig == NULL gracefully */
+	led_trigger_blink_oneshot(trig, &usb_blink_delay, &usb_blink_delay, 0);
+}
+EXPORT_SYMBOL_GPL(usb_led_activity);
+
+
+static int __init ledtrig_usb_init(void)
+{
+	led_trigger_register_simple("usb-gadget", &ledtrig_usb_gadget);
+	led_trigger_register_simple("usb-host", &ledtrig_usb_host);
+	return 0;
+}
+
+static void __exit ledtrig_usb_exit(void)
+{
+	led_trigger_unregister_simple(ledtrig_usb_gadget);
+	led_trigger_unregister_simple(ledtrig_usb_host);
+}
+
+module_init(ledtrig_usb_init);
+module_exit(ledtrig_usb_exit);
diff --git a/drivers/usb/common/usb-otg-fsm.c b/drivers/usb/common/usb-otg-fsm.c
new file mode 100644
index 000000000..61d538aa2
--- /dev/null
+++ b/drivers/usb/common/usb-otg-fsm.c
@@ -0,0 +1,367 @@
+/*
+ * OTG Finite State Machine from OTG spec
+ *
+ * Copyright (C) 2007,2008 Freescale Semiconductor, Inc.
+ *
+ * Author:	Li Yang <LeoLi@freescale.com>
+ *		Jerry Huang <Chang-Ming.Huang@freescale.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the  GNU General Public License along
+ * with this program; if not, write  to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/usb.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb/otg.h>
+#include <linux/usb/otg-fsm.h>
+
+/* Change USB protocol when there is a protocol change */
+static int otg_set_protocol(struct otg_fsm *fsm, int protocol)
+{
+	int ret = 0;
+
+	if (fsm->protocol != protocol) {
+		VDBG("Changing role fsm->protocol= %d; new protocol= %d\n",
+			fsm->protocol, protocol);
+		/* stop old protocol */
+		if (fsm->protocol == PROTO_HOST)
+			ret = otg_start_host(fsm, 0);
+		else if (fsm->protocol == PROTO_GADGET)
+			ret = otg_start_gadget(fsm, 0);
+		if (ret)
+			return ret;
+
+		/* start new protocol */
+		if (protocol == PROTO_HOST)
+			ret = otg_start_host(fsm, 1);
+		else if (protocol == PROTO_GADGET)
+			ret = otg_start_gadget(fsm, 1);
+		if (ret)
+			return ret;
+
+		fsm->protocol = protocol;
+		return 0;
+	}
+
+	return 0;
+}
+
+static int state_changed;
+
+/* Called when leaving a state.  Do state clean up jobs here */
+static void otg_leave_state(struct otg_fsm *fsm, enum usb_otg_state old_state)
+{
+	switch (old_state) {
+	case OTG_STATE_B_IDLE:
+		otg_del_timer(fsm, B_SE0_SRP);
+		fsm->b_se0_srp = 0;
+		fsm->adp_sns = 0;
+		fsm->adp_prb = 0;
+		break;
+	case OTG_STATE_B_SRP_INIT:
+		fsm->data_pulse = 0;
+		fsm->b_srp_done = 0;
+		break;
+	case OTG_STATE_B_PERIPHERAL:
+		break;
+	case OTG_STATE_B_WAIT_ACON:
+		otg_del_timer(fsm, B_ASE0_BRST);
+		fsm->b_ase0_brst_tmout = 0;
+		break;
+	case OTG_STATE_B_HOST:
+		break;
+	case OTG_STATE_A_IDLE:
+		fsm->adp_prb = 0;
+		break;
+	case OTG_STATE_A_WAIT_VRISE:
+		otg_del_timer(fsm, A_WAIT_VRISE);
+		fsm->a_wait_vrise_tmout = 0;
+		break;
+	case OTG_STATE_A_WAIT_BCON:
+		otg_del_timer(fsm, A_WAIT_BCON);
+		fsm->a_wait_bcon_tmout = 0;
+		break;
+	case OTG_STATE_A_HOST:
+		otg_del_timer(fsm, A_WAIT_ENUM);
+		break;
+	case OTG_STATE_A_SUSPEND:
+		otg_del_timer(fsm, A_AIDL_BDIS);
+		fsm->a_aidl_bdis_tmout = 0;
+		fsm->a_suspend_req_inf = 0;
+		break;
+	case OTG_STATE_A_PERIPHERAL:
+		otg_del_timer(fsm, A_BIDL_ADIS);
+		fsm->a_bidl_adis_tmout = 0;
+		break;
+	case OTG_STATE_A_WAIT_VFALL:
+		otg_del_timer(fsm, A_WAIT_VFALL);
+		fsm->a_wait_vfall_tmout = 0;
+		otg_del_timer(fsm, A_WAIT_VRISE);
+		break;
+	case OTG_STATE_A_VBUS_ERR:
+		break;
+	default:
+		break;
+	}
+}
+
+/* Called when entering a state */
+static int otg_set_state(struct otg_fsm *fsm, enum usb_otg_state new_state)
+{
+	state_changed = 1;
+	if (fsm->otg->state == new_state)
+		return 0;
+	VDBG("Set state: %s\n", usb_otg_state_string(new_state));
+	otg_leave_state(fsm, fsm->otg->state);
+	switch (new_state) {
+	case OTG_STATE_B_IDLE:
+		otg_drv_vbus(fsm, 0);
+		otg_chrg_vbus(fsm, 0);
+		otg_loc_conn(fsm, 0);
+		otg_loc_sof(fsm, 0);
+		/*
+		 * Driver is responsible for starting ADP probing
+		 * if ADP sensing times out.
+		 */
+		otg_start_adp_sns(fsm);
+		otg_set_protocol(fsm, PROTO_UNDEF);
+		otg_add_timer(fsm, B_SE0_SRP);
+		break;
+	case OTG_STATE_B_SRP_INIT:
+		otg_start_pulse(fsm);
+		otg_loc_sof(fsm, 0);
+		otg_set_protocol(fsm, PROTO_UNDEF);
+		otg_add_timer(fsm, B_SRP_FAIL);
+		break;
+	case OTG_STATE_B_PERIPHERAL:
+		otg_chrg_vbus(fsm, 0);
+		otg_loc_sof(fsm, 0);
+		otg_set_protocol(fsm, PROTO_GADGET);
+		otg_loc_conn(fsm, 1);
+		break;
+	case OTG_STATE_B_WAIT_ACON:
+		otg_chrg_vbus(fsm, 0);
+		otg_loc_conn(fsm, 0);
+		otg_loc_sof(fsm, 0);
+		otg_set_protocol(fsm, PROTO_HOST);
+		otg_add_timer(fsm, B_ASE0_BRST);
+		fsm->a_bus_suspend = 0;
+		break;
+	case OTG_STATE_B_HOST:
+		otg_chrg_vbus(fsm, 0);
+		otg_loc_conn(fsm, 0);
+		otg_loc_sof(fsm, 1);
+		otg_set_protocol(fsm, PROTO_HOST);
+		usb_bus_start_enum(fsm->otg->host,
+				fsm->otg->host->otg_port);
+		break;
+	case OTG_STATE_A_IDLE:
+		otg_drv_vbus(fsm, 0);
+		otg_chrg_vbus(fsm, 0);
+		otg_loc_conn(fsm, 0);
+		otg_loc_sof(fsm, 0);
+		otg_start_adp_prb(fsm);
+		otg_set_protocol(fsm, PROTO_HOST);
+		break;
+	case OTG_STATE_A_WAIT_VRISE:
+		otg_drv_vbus(fsm, 1);
+		otg_loc_conn(fsm, 0);
+		otg_loc_sof(fsm, 0);
+		otg_set_protocol(fsm, PROTO_HOST);
+		otg_add_timer(fsm, A_WAIT_VRISE);
+		break;
+	case OTG_STATE_A_WAIT_BCON:
+		otg_drv_vbus(fsm, 1);
+		otg_loc_conn(fsm, 0);
+		otg_loc_sof(fsm, 0);
+		otg_set_protocol(fsm, PROTO_HOST);
+		otg_add_timer(fsm, A_WAIT_BCON);
+		break;
+	case OTG_STATE_A_HOST:
+		otg_drv_vbus(fsm, 1);
+		otg_loc_conn(fsm, 0);
+		otg_loc_sof(fsm, 1);
+		otg_set_protocol(fsm, PROTO_HOST);
+		/*
+		 * When HNP is triggered while a_bus_req = 0, a_host will
+		 * suspend too fast to complete a_set_b_hnp_en
+		 */
+		if (!fsm->a_bus_req || fsm->a_suspend_req_inf)
+			otg_add_timer(fsm, A_WAIT_ENUM);
+		break;
+	case OTG_STATE_A_SUSPEND:
+		otg_drv_vbus(fsm, 1);
+		otg_loc_conn(fsm, 0);
+		otg_loc_sof(fsm, 0);
+		otg_set_protocol(fsm, PROTO_HOST);
+		otg_add_timer(fsm, A_AIDL_BDIS);
+
+		break;
+	case OTG_STATE_A_PERIPHERAL:
+		otg_loc_sof(fsm, 0);
+		otg_set_protocol(fsm, PROTO_GADGET);
+		otg_drv_vbus(fsm, 1);
+		otg_loc_conn(fsm, 1);
+		otg_add_timer(fsm, A_BIDL_ADIS);
+		break;
+	case OTG_STATE_A_WAIT_VFALL:
+		otg_drv_vbus(fsm, 0);
+		otg_loc_conn(fsm, 0);
+		otg_loc_sof(fsm, 0);
+		otg_set_protocol(fsm, PROTO_HOST);
+		otg_add_timer(fsm, A_WAIT_VFALL);
+		break;
+	case OTG_STATE_A_VBUS_ERR:
+		otg_drv_vbus(fsm, 0);
+		otg_loc_conn(fsm, 0);
+		otg_loc_sof(fsm, 0);
+		otg_set_protocol(fsm, PROTO_UNDEF);
+		break;
+	default:
+		break;
+	}
+
+	fsm->otg->state = new_state;
+	return 0;
+}
+
+/* State change judgement */
+int otg_statemachine(struct otg_fsm *fsm)
+{
+	enum usb_otg_state state;
+
+	mutex_lock(&fsm->lock);
+
+	state = fsm->otg->state;
+	state_changed = 0;
+	/* State machine state change judgement */
+
+	switch (state) {
+	case OTG_STATE_UNDEFINED:
+		VDBG("fsm->id = %d\n", fsm->id);
+		if (fsm->id)
+			otg_set_state(fsm, OTG_STATE_B_IDLE);
+		else
+			otg_set_state(fsm, OTG_STATE_A_IDLE);
+		break;
+	case OTG_STATE_B_IDLE:
+		if (!fsm->id)
+			otg_set_state(fsm, OTG_STATE_A_IDLE);
+		else if (fsm->b_sess_vld && fsm->otg->gadget)
+			otg_set_state(fsm, OTG_STATE_B_PERIPHERAL);
+		else if ((fsm->b_bus_req || fsm->adp_change || fsm->power_up) &&
+				fsm->b_ssend_srp && fsm->b_se0_srp)
+			otg_set_state(fsm, OTG_STATE_B_SRP_INIT);
+		break;
+	case OTG_STATE_B_SRP_INIT:
+		if (!fsm->id || fsm->b_srp_done)
+			otg_set_state(fsm, OTG_STATE_B_IDLE);
+		break;
+	case OTG_STATE_B_PERIPHERAL:
+		if (!fsm->id || !fsm->b_sess_vld)
+			otg_set_state(fsm, OTG_STATE_B_IDLE);
+		else if (fsm->b_bus_req && fsm->otg->
+				gadget->b_hnp_enable && fsm->a_bus_suspend)
+			otg_set_state(fsm, OTG_STATE_B_WAIT_ACON);
+		break;
+	case OTG_STATE_B_WAIT_ACON:
+		if (fsm->a_conn)
+			otg_set_state(fsm, OTG_STATE_B_HOST);
+		else if (!fsm->id || !fsm->b_sess_vld)
+			otg_set_state(fsm, OTG_STATE_B_IDLE);
+		else if (fsm->a_bus_resume || fsm->b_ase0_brst_tmout) {
+			fsm->b_ase0_brst_tmout = 0;
+			otg_set_state(fsm, OTG_STATE_B_PERIPHERAL);
+		}
+		break;
+	case OTG_STATE_B_HOST:
+		if (!fsm->id || !fsm->b_sess_vld)
+			otg_set_state(fsm, OTG_STATE_B_IDLE);
+		else if (!fsm->b_bus_req || !fsm->a_conn || fsm->test_device)
+			otg_set_state(fsm, OTG_STATE_B_PERIPHERAL);
+		break;
+	case OTG_STATE_A_IDLE:
+		if (fsm->id)
+			otg_set_state(fsm, OTG_STATE_B_IDLE);
+		else if (!fsm->a_bus_drop && (fsm->a_bus_req ||
+			  fsm->a_srp_det || fsm->adp_change || fsm->power_up))
+			otg_set_state(fsm, OTG_STATE_A_WAIT_VRISE);
+		break;
+	case OTG_STATE_A_WAIT_VRISE:
+		if (fsm->a_vbus_vld)
+			otg_set_state(fsm, OTG_STATE_A_WAIT_BCON);
+		else if (fsm->id || fsm->a_bus_drop ||
+				fsm->a_wait_vrise_tmout)
+			otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
+		break;
+	case OTG_STATE_A_WAIT_BCON:
+		if (!fsm->a_vbus_vld)
+			otg_set_state(fsm, OTG_STATE_A_VBUS_ERR);
+		else if (fsm->b_conn)
+			otg_set_state(fsm, OTG_STATE_A_HOST);
+		else if (fsm->id || fsm->a_bus_drop || fsm->a_wait_bcon_tmout)
+			otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
+		break;
+	case OTG_STATE_A_HOST:
+		if (fsm->id || fsm->a_bus_drop)
+			otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
+		else if ((!fsm->a_bus_req || fsm->a_suspend_req_inf) &&
+				fsm->otg->host->b_hnp_enable)
+			otg_set_state(fsm, OTG_STATE_A_SUSPEND);
+		else if (!fsm->b_conn)
+			otg_set_state(fsm, OTG_STATE_A_WAIT_BCON);
+		else if (!fsm->a_vbus_vld)
+			otg_set_state(fsm, OTG_STATE_A_VBUS_ERR);
+		break;
+	case OTG_STATE_A_SUSPEND:
+		if (!fsm->b_conn && fsm->otg->host->b_hnp_enable)
+			otg_set_state(fsm, OTG_STATE_A_PERIPHERAL);
+		else if (!fsm->b_conn && !fsm->otg->host->b_hnp_enable)
+			otg_set_state(fsm, OTG_STATE_A_WAIT_BCON);
+		else if (fsm->a_bus_req || fsm->b_bus_resume)
+			otg_set_state(fsm, OTG_STATE_A_HOST);
+		else if (fsm->id || fsm->a_bus_drop || fsm->a_aidl_bdis_tmout)
+			otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
+		else if (!fsm->a_vbus_vld)
+			otg_set_state(fsm, OTG_STATE_A_VBUS_ERR);
+		break;
+	case OTG_STATE_A_PERIPHERAL:
+		if (fsm->id || fsm->a_bus_drop)
+			otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
+		else if (fsm->a_bidl_adis_tmout || fsm->b_bus_suspend)
+			otg_set_state(fsm, OTG_STATE_A_WAIT_BCON);
+		else if (!fsm->a_vbus_vld)
+			otg_set_state(fsm, OTG_STATE_A_VBUS_ERR);
+		break;
+	case OTG_STATE_A_WAIT_VFALL:
+		if (fsm->a_wait_vfall_tmout)
+			otg_set_state(fsm, OTG_STATE_A_IDLE);
+		break;
+	case OTG_STATE_A_VBUS_ERR:
+		if (fsm->id || fsm->a_bus_drop || fsm->a_clr_err)
+			otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
+		break;
+	default:
+		break;
+	}
+	mutex_unlock(&fsm->lock);
+
+	VDBG("quit statemachine, changed = %d\n", state_changed);
+	return state_changed;
+}
+EXPORT_SYMBOL_GPL(otg_statemachine);