[mirror_ubuntu-jammy-kernel.git] / drivers / usb / common / usb-otg-fsm.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * 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>
 */

#include <linux/module.h>
#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>

#ifdef VERBOSE
#define VDBG(fmt, args...) pr_debug("[%s]  " fmt, \
				 __func__, ## args)
#else
#define VDBG(stuff...)	do {} while (0)
#endif

/* 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;
}

/* 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:
		if (fsm->otg->gadget)
			fsm->otg->gadget->host_request_flag = 0;
		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;
		if (fsm->otg->gadget)
			fsm->otg->gadget->host_request_flag = 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;
	}
}

static void otg_hnp_polling_work(struct work_struct *work)
{
	struct otg_fsm *fsm = container_of(to_delayed_work(work),
				struct otg_fsm, hnp_polling_work);
	struct usb_device *udev;
	enum usb_otg_state state = fsm->otg->state;
	u8 flag;
	int retval;

	if (state != OTG_STATE_A_HOST && state != OTG_STATE_B_HOST)
		return;

	udev = usb_hub_find_child(fsm->otg->host->root_hub, 1);
	if (!udev) {
		dev_err(fsm->otg->host->controller,
			"no usb dev connected, can't start HNP polling\n");
		return;
	}

	*fsm->host_req_flag = 0;
	/* Get host request flag from connected USB device */
	retval = usb_control_msg(udev,
				usb_rcvctrlpipe(udev, 0),
				USB_REQ_GET_STATUS,
				USB_DIR_IN | USB_RECIP_DEVICE,
				0,
				OTG_STS_SELECTOR,
				fsm->host_req_flag,
				1,
				USB_CTRL_GET_TIMEOUT);
	if (retval != 1) {
		dev_err(&udev->dev, "Get one byte OTG status failed\n");
		return;
	}

	flag = *fsm->host_req_flag;
	if (flag == 0) {
		/* Continue HNP polling */
		schedule_delayed_work(&fsm->hnp_polling_work,
					msecs_to_jiffies(T_HOST_REQ_POLL));
		return;
	} else if (flag != HOST_REQUEST_FLAG) {
		dev_err(&udev->dev, "host request flag %d is invalid\n", flag);
		return;
	}

	/* Host request flag is set */
	if (state == OTG_STATE_A_HOST) {
		/* Set b_hnp_enable */
		if (!fsm->otg->host->b_hnp_enable) {
			retval = usb_control_msg(udev,
					usb_sndctrlpipe(udev, 0),
					USB_REQ_SET_FEATURE, 0,
					USB_DEVICE_B_HNP_ENABLE,
					0, NULL, 0,
					USB_CTRL_SET_TIMEOUT);
			if (retval >= 0)
				fsm->otg->host->b_hnp_enable = 1;
		}
		fsm->a_bus_req = 0;
	} else if (state == OTG_STATE_B_HOST) {
		fsm->b_bus_req = 0;
	}

	otg_statemachine(fsm);
}

static void otg_start_hnp_polling(struct otg_fsm *fsm)
{
	/*
	 * The memory of host_req_flag should be allocated by
	 * controller driver, otherwise, hnp polling is not started.
	 */
	if (!fsm->host_req_flag)
		return;

	INIT_DELAYED_WORK(&fsm->hnp_polling_work, otg_hnp_polling_work);
	schedule_delayed_work(&fsm->hnp_polling_work,
					msecs_to_jiffies(T_HOST_REQ_POLL));
}

/* Called when entering a state */
static int otg_set_state(struct otg_fsm *fsm, enum usb_otg_state new_state)
{
	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);
		otg_start_hnp_polling(fsm);
		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);
		otg_start_hnp_polling(fsm);
		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;
	fsm->state_changed = 1;
	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;
	fsm->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", fsm->state_changed);
	return fsm->state_changed;
}
EXPORT_SYMBOL_GPL(otg_statemachine);
MODULE_LICENSE("GPL");
Commit	Line	Data
5fd54ace	1	// SPDX-License-Identifier: GPL-2.0+
0807c500 LY	2	/*
	3	* OTG Finite State Machine from OTG spec
	4	*
	5	* Copyright (C) 2007,2008 Freescale Semiconductor, Inc.
	6	*
	7	* Author: Li Yang <LeoLi@freescale.com>
	8	* Jerry Huang <Chang-Ming.Huang@freescale.com>
0807c500 LY	9	*/
0807c500 LY	10
ea1d39a3	11	#include <linux/module.h>
0807c500 LY	12	#include <linux/kernel.h>
0807c500 LY	13	#include <linux/types.h>
16e569e9	14	#include <linux/mutex.h>
0807c500 LY	15	#include <linux/delay.h>
	16	#include <linux/usb.h>
	17	#include <linux/usb/gadget.h>
	18	#include <linux/usb/otg.h>
5653668c	19	#include <linux/usb/otg-fsm.h>
0807c500	20
e92634cd RQ	21	#ifdef VERBOSE
	22	#define VDBG(fmt, args...) pr_debug("[%s] " fmt, \
	23	__func__, ## args)
	24	#else
	25	#define VDBG(stuff...) do {} while (0)
	26	#endif
	27
0807c500 LY	28	/* Change USB protocol when there is a protocol change */
	29	static int otg_set_protocol(struct otg_fsm *fsm, int protocol)
	30	{
	31	int ret = 0;
	32
	33	if (fsm->protocol != protocol) {
	34	VDBG("Changing role fsm->protocol= %d; new protocol= %d\n",
	35	fsm->protocol, protocol);
	36	/* stop old protocol */
	37	if (fsm->protocol == PROTO_HOST)
425d7101	38	ret = otg_start_host(fsm, 0);
0807c500	39	else if (fsm->protocol == PROTO_GADGET)
425d7101	40	ret = otg_start_gadget(fsm, 0);
0807c500 LY	41	if (ret)
	42	return ret;
	43
	44	/* start new protocol */
	45	if (protocol == PROTO_HOST)
425d7101	46	ret = otg_start_host(fsm, 1);
0807c500	47	else if (protocol == PROTO_GADGET)
425d7101	48	ret = otg_start_gadget(fsm, 1);
0807c500 LY	49	if (ret)
	50	return ret;
	51
	52	fsm->protocol = protocol;
	53	return 0;
	54	}
	55
	56	return 0;
	57	}
	58
0807c500	59	/* Called when leaving a state. Do state clean up jobs here */
7410f172	60	static void otg_leave_state(struct otg_fsm *fsm, enum usb_otg_state old_state)
0807c500 LY	61	{
	62	switch (old_state) {
	63	case OTG_STATE_B_IDLE:
f6de27ee	64	otg_del_timer(fsm, B_SE0_SRP);
0807c500	65	fsm->b_se0_srp = 0;
ec04996a AT	66	fsm->adp_sns = 0;
ec04996a AT	67	fsm->adp_prb = 0;
0807c500 LY	68	break;
0807c500 LY	69	case OTG_STATE_B_SRP_INIT:
ec04996a	70	fsm->data_pulse = 0;
0807c500 LY	71	fsm->b_srp_done = 0;
	72	break;
	73	case OTG_STATE_B_PERIPHERAL:
ae57e97a LJ	74	if (fsm->otg->gadget)
ae57e97a LJ	75	fsm->otg->gadget->host_request_flag = 0;
0807c500 LY	76	break;
0807c500 LY	77	case OTG_STATE_B_WAIT_ACON:
f6de27ee	78	otg_del_timer(fsm, B_ASE0_BRST);
0807c500 LY	79	fsm->b_ase0_brst_tmout = 0;
	80	break;
	81	case OTG_STATE_B_HOST:
	82	break;
	83	case OTG_STATE_A_IDLE:
ec04996a	84	fsm->adp_prb = 0;
0807c500 LY	85	break;
0807c500 LY	86	case OTG_STATE_A_WAIT_VRISE:
f6de27ee	87	otg_del_timer(fsm, A_WAIT_VRISE);
0807c500 LY	88	fsm->a_wait_vrise_tmout = 0;
	89	break;
	90	case OTG_STATE_A_WAIT_BCON:
f6de27ee	91	otg_del_timer(fsm, A_WAIT_BCON);
0807c500 LY	92	fsm->a_wait_bcon_tmout = 0;
	93	break;
	94	case OTG_STATE_A_HOST:
f6de27ee	95	otg_del_timer(fsm, A_WAIT_ENUM);
0807c500 LY	96	break;
0807c500 LY	97	case OTG_STATE_A_SUSPEND:
f6de27ee	98	otg_del_timer(fsm, A_AIDL_BDIS);
0807c500	99	fsm->a_aidl_bdis_tmout = 0;
cff4dab4	100	fsm->a_suspend_req_inf = 0;
0807c500 LY	101	break;
0807c500 LY	102	case OTG_STATE_A_PERIPHERAL:
3294908b AT	103	otg_del_timer(fsm, A_BIDL_ADIS);
3294908b AT	104	fsm->a_bidl_adis_tmout = 0;
ae57e97a LJ	105	if (fsm->otg->gadget)
ae57e97a LJ	106	fsm->otg->gadget->host_request_flag = 0;
0807c500 LY	107	break;
0807c500 LY	108	case OTG_STATE_A_WAIT_VFALL:
3294908b AT	109	otg_del_timer(fsm, A_WAIT_VFALL);
3294908b AT	110	fsm->a_wait_vfall_tmout = 0;
f6de27ee	111	otg_del_timer(fsm, A_WAIT_VRISE);
0807c500 LY	112	break;
	113	case OTG_STATE_A_VBUS_ERR:
	114	break;
	115	default:
	116	break;
	117	}
	118	}
	119
ae57e97a LJ	120	static void otg_hnp_polling_work(struct work_struct *work)
	121	{
	122	struct otg_fsm *fsm = container_of(to_delayed_work(work),
	123	struct otg_fsm, hnp_polling_work);
	124	struct usb_device *udev;
	125	enum usb_otg_state state = fsm->otg->state;
	126	u8 flag;
	127	int retval;
	128
	129	if (state != OTG_STATE_A_HOST && state != OTG_STATE_B_HOST)
	130	return;
	131
	132	udev = usb_hub_find_child(fsm->otg->host->root_hub, 1);
	133	if (!udev) {
	134	dev_err(fsm->otg->host->controller,
	135	"no usb dev connected, can't start HNP polling\n");
	136	return;
	137	}
	138
	139	*fsm->host_req_flag = 0;
	140	/* Get host request flag from connected USB device */
	141	retval = usb_control_msg(udev,
	142	usb_rcvctrlpipe(udev, 0),
	143	USB_REQ_GET_STATUS,
	144	USB_DIR_IN \| USB_RECIP_DEVICE,
	145	0,
	146	OTG_STS_SELECTOR,
	147	fsm->host_req_flag,
	148	1,
	149	USB_CTRL_GET_TIMEOUT);
	150	if (retval != 1) {
	151	dev_err(&udev->dev, "Get one byte OTG status failed\n");
	152	return;
	153	}
	154
	155	flag = *fsm->host_req_flag;
	156	if (flag == 0) {
	157	/* Continue HNP polling */
	158	schedule_delayed_work(&fsm->hnp_polling_work,
	159	msecs_to_jiffies(T_HOST_REQ_POLL));
	160	return;
	161	} else if (flag != HOST_REQUEST_FLAG) {
	162	dev_err(&udev->dev, "host request flag %d is invalid\n", flag);
	163	return;
	164	}
	165
	166	/* Host request flag is set */
	167	if (state == OTG_STATE_A_HOST) {
	168	/* Set b_hnp_enable */
	169	if (!fsm->otg->host->b_hnp_enable) {
	170	retval = usb_control_msg(udev,
	171	usb_sndctrlpipe(udev, 0),
	172	USB_REQ_SET_FEATURE, 0,
	173	USB_DEVICE_B_HNP_ENABLE,
	174	0, NULL, 0,
	175	USB_CTRL_SET_TIMEOUT);
	176	if (retval >= 0)
	177	fsm->otg->host->b_hnp_enable = 1;
	178	}
	179	fsm->a_bus_req = 0;
	180	} else if (state == OTG_STATE_B_HOST) {
	181	fsm->b_bus_req = 0;
	182	}
	183
184	otg_statemachine(fsm);
185	}
186
187	static void otg_start_hnp_polling(struct otg_fsm *fsm)
188	{
189	/*
190	* The memory of host_req_flag should be allocated by
191	* controller driver, otherwise, hnp polling is not started.
192	*/
193	if (!fsm->host_req_flag)
194	return;
195
196	INIT_DELAYED_WORK(&fsm->hnp_polling_work, otg_hnp_polling_work);
197	schedule_delayed_work(&fsm->hnp_polling_work,
198	msecs_to_jiffies(T_HOST_REQ_POLL));
199	}
200
0807c500	201	/* Called when entering a state */
7410f172	202	static int otg_set_state(struct otg_fsm *fsm, enum usb_otg_state new_state)
0807c500	203	{
e47d9254	204	if (fsm->otg->state == new_state)
0807c500	205	return 0;
42c0bf1c	206	VDBG("Set state: %s\n", usb_otg_state_string(new_state));
e47d9254	207	otg_leave_state(fsm, fsm->otg->state);
0807c500 LY	208	switch (new_state) {
	209	case OTG_STATE_B_IDLE:
	210	otg_drv_vbus(fsm, 0);
	211	otg_chrg_vbus(fsm, 0);
	212	otg_loc_conn(fsm, 0);
	213	otg_loc_sof(fsm, 0);
ec04996a AT	214	/*
	215	* Driver is responsible for starting ADP probing
	216	* if ADP sensing times out.
	217	*/
	218	otg_start_adp_sns(fsm);
0807c500	219	otg_set_protocol(fsm, PROTO_UNDEF);
f6de27ee	220	otg_add_timer(fsm, B_SE0_SRP);
0807c500 LY	221	break;
	222	case OTG_STATE_B_SRP_INIT:
	223	otg_start_pulse(fsm);
	224	otg_loc_sof(fsm, 0);
	225	otg_set_protocol(fsm, PROTO_UNDEF);
f6de27ee	226	otg_add_timer(fsm, B_SRP_FAIL);
0807c500 LY	227	break;
	228	case OTG_STATE_B_PERIPHERAL:
	229	otg_chrg_vbus(fsm, 0);
0807c500 LY	230	otg_loc_sof(fsm, 0);
0807c500 LY	231	otg_set_protocol(fsm, PROTO_GADGET);
a886bd92	232	otg_loc_conn(fsm, 1);
0807c500 LY	233	break;
	234	case OTG_STATE_B_WAIT_ACON:
	235	otg_chrg_vbus(fsm, 0);
	236	otg_loc_conn(fsm, 0);
	237	otg_loc_sof(fsm, 0);
	238	otg_set_protocol(fsm, PROTO_HOST);
f6de27ee	239	otg_add_timer(fsm, B_ASE0_BRST);
0807c500 LY	240	fsm->a_bus_suspend = 0;
	241	break;
	242	case OTG_STATE_B_HOST:
	243	otg_chrg_vbus(fsm, 0);
	244	otg_loc_conn(fsm, 0);
	245	otg_loc_sof(fsm, 1);
	246	otg_set_protocol(fsm, PROTO_HOST);
7e062c0f HK	247	usb_bus_start_enum(fsm->otg->host,
7e062c0f HK	248	fsm->otg->host->otg_port);
ae57e97a	249	otg_start_hnp_polling(fsm);
0807c500 LY	250	break;
	251	case OTG_STATE_A_IDLE:
	252	otg_drv_vbus(fsm, 0);
	253	otg_chrg_vbus(fsm, 0);
	254	otg_loc_conn(fsm, 0);
	255	otg_loc_sof(fsm, 0);
ec04996a	256	otg_start_adp_prb(fsm);
0807c500 LY	257	otg_set_protocol(fsm, PROTO_HOST);
	258	break;
	259	case OTG_STATE_A_WAIT_VRISE:
	260	otg_drv_vbus(fsm, 1);
	261	otg_loc_conn(fsm, 0);
	262	otg_loc_sof(fsm, 0);
	263	otg_set_protocol(fsm, PROTO_HOST);
f6de27ee	264	otg_add_timer(fsm, A_WAIT_VRISE);
0807c500 LY	265	break;
	266	case OTG_STATE_A_WAIT_BCON:
	267	otg_drv_vbus(fsm, 1);
	268	otg_loc_conn(fsm, 0);
	269	otg_loc_sof(fsm, 0);
	270	otg_set_protocol(fsm, PROTO_HOST);
f6de27ee	271	otg_add_timer(fsm, A_WAIT_BCON);
0807c500 LY	272	break;
	273	case OTG_STATE_A_HOST:
	274	otg_drv_vbus(fsm, 1);
	275	otg_loc_conn(fsm, 0);
	276	otg_loc_sof(fsm, 1);
	277	otg_set_protocol(fsm, PROTO_HOST);
	278	/*
	279	* When HNP is triggered while a_bus_req = 0, a_host will
	280	* suspend too fast to complete a_set_b_hnp_en
	281	*/
cff4dab4	282	if (!fsm->a_bus_req \|\| fsm->a_suspend_req_inf)
f6de27ee	283	otg_add_timer(fsm, A_WAIT_ENUM);
ae57e97a	284	otg_start_hnp_polling(fsm);
0807c500 LY	285	break;
	286	case OTG_STATE_A_SUSPEND:
	287	otg_drv_vbus(fsm, 1);
	288	otg_loc_conn(fsm, 0);
	289	otg_loc_sof(fsm, 0);
	290	otg_set_protocol(fsm, PROTO_HOST);
f6de27ee	291	otg_add_timer(fsm, A_AIDL_BDIS);
0807c500 LY	292
	293	break;
	294	case OTG_STATE_A_PERIPHERAL:
0807c500 LY	295	otg_loc_sof(fsm, 0);
	296	otg_set_protocol(fsm, PROTO_GADGET);
	297	otg_drv_vbus(fsm, 1);
a886bd92	298	otg_loc_conn(fsm, 1);
3294908b	299	otg_add_timer(fsm, A_BIDL_ADIS);
0807c500 LY	300	break;
	301	case OTG_STATE_A_WAIT_VFALL:
	302	otg_drv_vbus(fsm, 0);
	303	otg_loc_conn(fsm, 0);
	304	otg_loc_sof(fsm, 0);
	305	otg_set_protocol(fsm, PROTO_HOST);
3294908b	306	otg_add_timer(fsm, A_WAIT_VFALL);
0807c500 LY	307	break;
	308	case OTG_STATE_A_VBUS_ERR:
	309	otg_drv_vbus(fsm, 0);
	310	otg_loc_conn(fsm, 0);
	311	otg_loc_sof(fsm, 0);
	312	otg_set_protocol(fsm, PROTO_UNDEF);
	313	break;
	314	default:
	315	break;
	316	}
	317
e47d9254	318	fsm->otg->state = new_state;
4e332df6	319	fsm->state_changed = 1;
0807c500 LY	320	return 0;
	321	}
	322
	323	/* State change judgement */
	324	int otg_statemachine(struct otg_fsm *fsm)
	325	{
	326	enum usb_otg_state state;
0807c500	327
16e569e9	328	mutex_lock(&fsm->lock);
0807c500	329
e47d9254	330	state = fsm->otg->state;
4e332df6	331	fsm->state_changed = 0;
0807c500 LY	332	/* State machine state change judgement */
	333
	334	switch (state) {
	335	case OTG_STATE_UNDEFINED:
	336	VDBG("fsm->id = %d\n", fsm->id);
	337	if (fsm->id)
	338	otg_set_state(fsm, OTG_STATE_B_IDLE);
	339	else
	340	otg_set_state(fsm, OTG_STATE_A_IDLE);
	341	break;
	342	case OTG_STATE_B_IDLE:
	343	if (!fsm->id)
	344	otg_set_state(fsm, OTG_STATE_A_IDLE);
7e062c0f	345	else if (fsm->b_sess_vld && fsm->otg->gadget)
0807c500	346	otg_set_state(fsm, OTG_STATE_B_PERIPHERAL);
ec04996a AT	347	else if ((fsm->b_bus_req \|\| fsm->adp_change \|\| fsm->power_up) &&
ec04996a AT	348	fsm->b_ssend_srp && fsm->b_se0_srp)
0807c500 LY	349	otg_set_state(fsm, OTG_STATE_B_SRP_INIT);
	350	break;
	351	case OTG_STATE_B_SRP_INIT:
	352	if (!fsm->id \|\| fsm->b_srp_done)
	353	otg_set_state(fsm, OTG_STATE_B_IDLE);
	354	break;
	355	case OTG_STATE_B_PERIPHERAL:
	356	if (!fsm->id \|\| !fsm->b_sess_vld)
	357	otg_set_state(fsm, OTG_STATE_B_IDLE);
7e062c0f	358	else if (fsm->b_bus_req && fsm->otg->
0807c500 LY	359	gadget->b_hnp_enable && fsm->a_bus_suspend)
	360	otg_set_state(fsm, OTG_STATE_B_WAIT_ACON);
	361	break;
	362	case OTG_STATE_B_WAIT_ACON:
	363	if (fsm->a_conn)
	364	otg_set_state(fsm, OTG_STATE_B_HOST);
	365	else if (!fsm->id \|\| !fsm->b_sess_vld)
	366	otg_set_state(fsm, OTG_STATE_B_IDLE);
	367	else if (fsm->a_bus_resume \|\| fsm->b_ase0_brst_tmout) {
	368	fsm->b_ase0_brst_tmout = 0;
	369	otg_set_state(fsm, OTG_STATE_B_PERIPHERAL);
	370	}
	371	break;
	372	case OTG_STATE_B_HOST:
	373	if (!fsm->id \|\| !fsm->b_sess_vld)
	374	otg_set_state(fsm, OTG_STATE_B_IDLE);
ec04996a	375	else if (!fsm->b_bus_req \|\| !fsm->a_conn \|\| fsm->test_device)
0807c500 LY	376	otg_set_state(fsm, OTG_STATE_B_PERIPHERAL);
	377	break;
	378	case OTG_STATE_A_IDLE:
	379	if (fsm->id)
	380	otg_set_state(fsm, OTG_STATE_B_IDLE);
ec04996a AT	381	else if (!fsm->a_bus_drop && (fsm->a_bus_req \|\|
ec04996a AT	382	fsm->a_srp_det \|\| fsm->adp_change \|\| fsm->power_up))
0807c500 LY	383	otg_set_state(fsm, OTG_STATE_A_WAIT_VRISE);
	384	break;
	385	case OTG_STATE_A_WAIT_VRISE:
2284bb35	386	if (fsm->a_vbus_vld)
0807c500	387	otg_set_state(fsm, OTG_STATE_A_WAIT_BCON);
2284bb35 LJ	388	else if (fsm->id \|\| fsm->a_bus_drop \|\|
	389	fsm->a_wait_vrise_tmout)
	390	otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
0807c500 LY	391	break;
	392	case OTG_STATE_A_WAIT_BCON:
	393	if (!fsm->a_vbus_vld)
	394	otg_set_state(fsm, OTG_STATE_A_VBUS_ERR);
	395	else if (fsm->b_conn)
	396	otg_set_state(fsm, OTG_STATE_A_HOST);
66668991	397	else if (fsm->id \|\| fsm->a_bus_drop \|\| fsm->a_wait_bcon_tmout)
0807c500 LY	398	otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
	399	break;
	400	case OTG_STATE_A_HOST:
8bebbe8d LJ	401	if (fsm->id \|\| fsm->a_bus_drop)
	402	otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
	403	else if ((!fsm->a_bus_req \|\| fsm->a_suspend_req_inf) &&
7e062c0f	404	fsm->otg->host->b_hnp_enable)
0807c500	405	otg_set_state(fsm, OTG_STATE_A_SUSPEND);
8bebbe8d	406	else if (!fsm->b_conn)
0807c500 LY	407	otg_set_state(fsm, OTG_STATE_A_WAIT_BCON);
	408	else if (!fsm->a_vbus_vld)
	409	otg_set_state(fsm, OTG_STATE_A_VBUS_ERR);
	410	break;
	411	case OTG_STATE_A_SUSPEND:
7e062c0f	412	if (!fsm->b_conn && fsm->otg->host->b_hnp_enable)
0807c500	413	otg_set_state(fsm, OTG_STATE_A_PERIPHERAL);
7e062c0f	414	else if (!fsm->b_conn && !fsm->otg->host->b_hnp_enable)
0807c500 LY	415	otg_set_state(fsm, OTG_STATE_A_WAIT_BCON);
	416	else if (fsm->a_bus_req \|\| fsm->b_bus_resume)
	417	otg_set_state(fsm, OTG_STATE_A_HOST);
	418	else if (fsm->id \|\| fsm->a_bus_drop \|\| fsm->a_aidl_bdis_tmout)
	419	otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
	420	else if (!fsm->a_vbus_vld)
	421	otg_set_state(fsm, OTG_STATE_A_VBUS_ERR);
	422	break;
	423	case OTG_STATE_A_PERIPHERAL:
	424	if (fsm->id \|\| fsm->a_bus_drop)
	425	otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
3294908b	426	else if (fsm->a_bidl_adis_tmout \|\| fsm->b_bus_suspend)
0807c500 LY	427	otg_set_state(fsm, OTG_STATE_A_WAIT_BCON);
	428	else if (!fsm->a_vbus_vld)
	429	otg_set_state(fsm, OTG_STATE_A_VBUS_ERR);
	430	break;
	431	case OTG_STATE_A_WAIT_VFALL:
8bebbe8d	432	if (fsm->a_wait_vfall_tmout)
0807c500 LY	433	otg_set_state(fsm, OTG_STATE_A_IDLE);
	434	break;
	435	case OTG_STATE_A_VBUS_ERR:
	436	if (fsm->id \|\| fsm->a_bus_drop \|\| fsm->a_clr_err)
	437	otg_set_state(fsm, OTG_STATE_A_WAIT_VFALL);
	438	break;
	439	default:
	440	break;
	441	}
16da4b17	442	mutex_unlock(&fsm->lock);
0807c500	443
4e332df6 RQ	444	VDBG("quit statemachine, changed = %d\n", fsm->state_changed);
4e332df6 RQ	445	return fsm->state_changed;
0807c500	446	}
be696aac	447	EXPORT_SYMBOL_GPL(otg_statemachine);
ea1d39a3	448	MODULE_LICENSE("GPL");