// SPDX-License-Identifier: GPL-2.0+
/* Copyright (C) 2007,2008 Freescale Semiconductor, Inc.
*
* 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.
*/
#ifndef __LINUX_USB_OTG_FSM_H
#define __LINUX_USB_OTG_FSM_H
#include <linux/mutex.h>
#include <linux/errno.h>
#define PROTO_UNDEF (0)
#define PROTO_HOST (1)
#define PROTO_GADGET (2)
#define OTG_STS_SELECTOR 0xF000 /* OTG status selector, according to
* OTG and EH 2.0 Chapter 6.2.3
* Table:6-4
*/
#define HOST_REQUEST_FLAG 1 /* Host request flag, according to
* OTG and EH 2.0 Charpter 6.2.3
* Table:6-5
*/
#define T_HOST_REQ_POLL (1500) /* 1500ms, HNP polling interval */
enum otg_fsm_timer {
/* Standard OTG timers */
A_WAIT_VRISE,
A_WAIT_VFALL,
A_WAIT_BCON,
A_AIDL_BDIS,
B_ASE0_BRST,
A_BIDL_ADIS,
B_AIDL_BDIS,
/* Auxiliary timers */
B_SE0_SRP,
B_SRP_FAIL,
A_WAIT_ENUM,
B_DATA_PLS,
B_SSEND_SRP,
NUM_OTG_FSM_TIMERS,
};
/**
* struct otg_fsm - OTG state machine according to the OTG spec
*
* OTG hardware Inputs
*
* Common inputs for A and B device
* @id: TRUE for B-device, FALSE for A-device.
* @adp_change: TRUE when current ADP measurement (n) value, compared to the
* ADP measurement taken at n-2, differs by more than CADP_THR
* @power_up: TRUE when the OTG device first powers up its USB system and
* ADP measurement taken if ADP capable
*
* A-Device state inputs
* @a_srp_det: TRUE if the A-device detects SRP
* @a_vbus_vld: TRUE when VBUS voltage is in regulation
* @b_conn: TRUE if the A-device detects connection from the B-device
* @a_bus_resume: TRUE when the B-device detects that the A-device is signaling
* a resume (K state)
* B-Device state inputs
* @a_bus_suspend: TRUE when the B-device detects that the A-device has put the
* bus into suspend
* @a_conn: TRUE if the B-device detects a connection from the A-device
* @b_se0_srp: TRUE when the line has been at SE0 for more than the minimum
* time before generating SRP
* @b_ssend_srp: TRUE when the VBUS has been below VOTG_SESS_VLD for more than
* the minimum time before generating SRP
* @b_sess_vld: TRUE when the B-device detects that the voltage on VBUS is
* above VOTG_SESS_VLD
* @test_device: TRUE when the B-device switches to B-Host and detects an OTG
* test device. This must be set by host/hub driver
*
* Application inputs (A-Device)
* @a_bus_drop: TRUE when A-device application needs to power down the bus
* @a_bus_req: TRUE when A-device application wants to use the bus.
* FALSE to suspend the bus
*
* Application inputs (B-Device)
* @b_bus_req: TRUE during the time that the Application running on the
* B-device wants to use the bus
*
* Auxilary inputs (OTG v1.3 only. Obsolete now.)
* @a_sess_vld: TRUE if the A-device detects that VBUS is above VA_SESS_VLD
* @b_bus_suspend: TRUE when the A-device detects that the B-device has put
* the bus into suspend
* @b_bus_resume: TRUE when the A-device detects that the B-device is signaling
* resume on the bus
*
* OTG Output status. Read only for users. Updated by OTG FSM helpers defined
* in this file
*
* Outputs for Both A and B device
* @drv_vbus: TRUE when A-device is driving VBUS
* @loc_conn: TRUE when the local device has signaled that it is connected
* to the bus
* @loc_sof: TRUE when the local device is generating activity on the bus
* @adp_prb: TRUE when the local device is in the process of doing
* ADP probing
*
* Outputs for B-device state
* @adp_sns: TRUE when the B-device is in the process of carrying out
* ADP sensing
* @data_pulse: TRUE when the B-device is performing data line pulsing
*
* Internal Variables
*
* a_set_b_hnp_en: TRUE when the A-device has successfully set the
* b_hnp_enable bit in the B-device.
* Unused as OTG fsm uses otg->host->b_hnp_enable instead
* b_srp_done: TRUE when the B-device has completed initiating SRP
* b_hnp_enable: TRUE when the B-device has accepted the
* SetFeature(b_hnp_enable) B-device.
* Unused as OTG fsm uses otg->gadget->b_hnp_enable instead
* a_clr_err: Asserted (by application ?) to clear a_vbus_err due to an
* overcurrent condition and causes the A-device to transition
* to a_wait_vfall
*/
struct otg_fsm {
/* Input */
int id;
int adp_change;
int power_up;
int a_srp_det;
int a_vbus_vld;
int b_conn;
int a_bus_resume;
int a_bus_suspend;
int a_conn;
int b_se0_srp;
int b_ssend_srp;
int b_sess_vld;
int test_device;
int a_bus_drop;
int a_bus_req;
int b_bus_req;
/* Auxilary inputs */
int a_sess_vld;
int b_bus_resume;
int b_bus_suspend;
/* Output */
int drv_vbus;
int loc_conn;
int loc_sof;
int adp_prb;
int adp_sns;
int data_pulse;
/* Internal variables */
int a_set_b_hnp_en;
int b_srp_done;
int b_hnp_enable;
int a_clr_err;
/* Informative variables. All unused as of now */
int a_bus_drop_inf;
int a_bus_req_inf;
int a_clr_err_inf;
int b_bus_req_inf;
/* Auxilary informative variables */
int a_suspend_req_inf;
/* Timeout indicator for timers */
int a_wait_vrise_tmout;
int a_wait_vfall_tmout;
int a_wait_bcon_tmout;
int a_aidl_bdis_tmout;
int b_ase0_brst_tmout;
int a_bidl_adis_tmout;
struct otg_fsm_ops *ops;
struct usb_otg *otg;
/* Current usb protocol used: 0:undefine; 1:host; 2:client */
int protocol;
struct mutex lock;
u8 *host_req_flag;
struct delayed_work hnp_polling_work;
bool state_changed;
};
struct otg_fsm_ops {
void (*chrg_vbus)(struct otg_fsm *fsm, int on);
void (*drv_vbus)(struct otg_fsm *fsm, int on);
void (*loc_conn)(struct otg_fsm *fsm, int on);
void (*loc_sof)(struct otg_fsm *fsm, int on);
void (*start_pulse)(struct otg_fsm *fsm);
void (*start_adp_prb)(struct otg_fsm *fsm);
void (*start_adp_sns)(struct otg_fsm *fsm);
void (*add_timer)(struct otg_fsm *fsm, enum otg_fsm_timer timer);
void (*del_timer)(struct otg_fsm *fsm, enum otg_fsm_timer timer);
int (*start_host)(struct otg_fsm *fsm, int on);
int (*start_gadget)(struct otg_fsm *fsm, int on);
};
static inline int otg_chrg_vbus(struct otg_fsm *fsm, int on)
{
if (!fsm->ops->chrg_vbus)
return -EOPNOTSUPP;
fsm->ops->chrg_vbus(fsm, on);
return 0;
}
static inline int otg_drv_vbus(struct otg_fsm *fsm, int on)
{
if (!fsm->ops->drv_vbus)
return -EOPNOTSUPP;
if (fsm->drv_vbus != on) {
fsm->drv_vbus = on;
fsm->ops->drv_vbus(fsm, on);
}
return 0;
}
static inline int otg_loc_conn(struct otg_fsm *fsm, int on)
{
if (!fsm->ops->loc_conn)
return -EOPNOTSUPP;
if (fsm->loc_conn != on) {
fsm->loc_conn = on;
fsm->ops->loc_conn(fsm, on);
}
return 0;
}
static inline int otg_loc_sof(struct otg_fsm *fsm, int on)
{
if (!fsm->ops->loc_sof)
return -EOPNOTSUPP;
if (fsm->loc_sof != on) {
fsm->loc_sof = on;
fsm->ops->loc_sof(fsm, on);
}
return 0;
}
static inline int otg_start_pulse(struct otg_fsm *fsm)
{
if (!fsm->ops->start_pulse)
return -EOPNOTSUPP;
if (!fsm->data_pulse) {
fsm->data_pulse = 1;
fsm->ops->start_pulse(fsm);
}
return 0;
}
static inline int otg_start_adp_prb(struct otg_fsm *fsm)
{
if (!fsm->ops->start_adp_prb)
return -EOPNOTSUPP;
if (!fsm->adp_prb) {
fsm->adp_sns = 0;
fsm->adp_prb = 1;
fsm->ops->start_adp_prb(fsm);
}
return 0;
}
static inline int otg_start_adp_sns(struct otg_fsm *fsm)
{
if (!fsm->ops->start_adp_sns)
return -EOPNOTSUPP;
if (!fsm->adp_sns) {
fsm->adp_sns = 1;
fsm->ops->start_adp_sns(fsm);
}
return 0;
}
static inline int otg_add_timer(struct otg_fsm *fsm, enum otg_fsm_timer timer)
{
if (!fsm->ops->add_timer)
return -EOPNOTSUPP;
fsm->ops->add_timer(fsm, timer);
return 0;
}
static inline int otg_del_timer(struct otg_fsm *fsm, enum otg_fsm_timer timer)
{
if (!fsm->ops->del_timer)
return -EOPNOTSUPP;
fsm->ops->del_timer(fsm, timer);
return 0;
}
static inline int otg_start_host(struct otg_fsm *fsm, int on)
{
if (!fsm->ops->start_host)
return -EOPNOTSUPP;
return fsm->ops->start_host(fsm, on);
}
static inline int otg_start_gadget(struct otg_fsm *fsm, int on)
{
if (!fsm->ops->start_gadget)
return -EOPNOTSUPP;
return fsm->ops->start_gadget(fsm, on);
}
int otg_statemachine(struct otg_fsm *fsm);
#endif /* __LINUX_USB_OTG_FSM_H */