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alistair23-linux/drivers/usb/common/usb-otg-fsm.c
Greg Kroah-Hartman 366122afb8 USB: common: Remove redundant license text 
Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner.  So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text.  And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Peter Chen <Peter.Chen@nxp.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04 11:55:39 +01:00

449 lines
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// 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");
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