linux/drivers/usb/common/usb-otg-fsm.c
Li Jun ae57e97a95 usb: common: otg-fsm: add HNP polling support
Adds HNP polling timer when transits to host state, the OTG status
request will be sent to peripheral after timeout, if host request flag
is set, it will switch to peripheral state, otherwise it will repeat HNP
polling every 1.5s and maintain the current session.

Acked-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-03-04 15:14:36 +02:00

455 lines
12 KiB
C

/*
* 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:
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)
{
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);
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;
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);