LXR linux/include/linux/usb/otg-fsm.h

   1// SPDX-License-Identifier: GPL-2.0+
   2/* Copyright (C) 2007,2008 Freescale Semiconductor, Inc.
   3 *
   4 * This program is free software; you can redistribute  it and/or modify it
   5 * under  the terms of  the GNU General  Public License as published by the
   6 * Free Software Foundation;  either version 2 of the  License, or (at your
   7 * option) any later version.
   8 *
   9 * This program is distributed in the hope that it will be useful, but
  10 * WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12 * General Public License for more details.
  13 *
  14 * You should have received a copy of the  GNU General Public License along
  15 * with this program; if not, write  to the Free Software Foundation, Inc.,
  16 * 675 Mass Ave, Cambridge, MA 02139, USA.
  17 */
  18
  19#ifndef __LINUX_USB_OTG_FSM_H
  20#define __LINUX_USB_OTG_FSM_H
  21
  22#include <linux/mutex.h>
  23#include <linux/errno.h>
  24
  25#define PROTO_UNDEF     (0)
  26#define PROTO_HOST      (1)
  27#define PROTO_GADGET    (2)
  28
  29#define OTG_STS_SELECTOR        0xF000  /* OTG status selector, according to
  30                                         * OTG and EH 2.0 Chapter 6.2.3
  31                                         * Table:6-4
  32                                         */
  33
  34#define HOST_REQUEST_FLAG       1       /* Host request flag, according to
  35                                         * OTG and EH 2.0 Charpter 6.2.3
  36                                         * Table:6-5
  37                                         */
  38
  39#define T_HOST_REQ_POLL         (1500)  /* 1500ms, HNP polling interval */
  40
  41enum otg_fsm_timer {
  42        /* Standard OTG timers */
  43        A_WAIT_VRISE,
  44        A_WAIT_VFALL,
  45        A_WAIT_BCON,
  46        A_AIDL_BDIS,
  47        B_ASE0_BRST,
  48        A_BIDL_ADIS,
  49        B_AIDL_BDIS,
  50
  51        /* Auxiliary timers */
  52        B_SE0_SRP,
  53        B_SRP_FAIL,
  54        A_WAIT_ENUM,
  55        B_DATA_PLS,
  56        B_SSEND_SRP,
  57
  58        NUM_OTG_FSM_TIMERS,
  59};
  60
  61/**
  62 * struct otg_fsm - OTG state machine according to the OTG spec
  63 *
  64 * OTG hardware Inputs
  65 *
  66 *      Common inputs for A and B device
  67 * @id:         TRUE for B-device, FALSE for A-device.
  68 * @adp_change: TRUE when current ADP measurement (n) value, compared to the
  69 *              ADP measurement taken at n-2, differs by more than CADP_THR
  70 * @power_up:   TRUE when the OTG device first powers up its USB system and
  71 *              ADP measurement taken if ADP capable
  72 *
  73 *      A-Device state inputs
  74 * @a_srp_det:  TRUE if the A-device detects SRP
  75 * @a_vbus_vld: TRUE when VBUS voltage is in regulation
  76 * @b_conn:     TRUE if the A-device detects connection from the B-device
  77 * @a_bus_resume: TRUE when the B-device detects that the A-device is signaling
  78 *                a resume (K state)
  79 *      B-Device state inputs
  80 * @a_bus_suspend: TRUE when the B-device detects that the A-device has put the
  81 *              bus into suspend
  82 * @a_conn:     TRUE if the B-device detects a connection from the A-device
  83 * @b_se0_srp:  TRUE when the line has been at SE0 for more than the minimum
  84 *              time before generating SRP
  85 * @b_ssend_srp: TRUE when the VBUS has been below VOTG_SESS_VLD for more than
  86 *               the minimum time before generating SRP
  87 * @b_sess_vld: TRUE when the B-device detects that the voltage on VBUS is
  88 *              above VOTG_SESS_VLD
  89 * @test_device: TRUE when the B-device switches to B-Host and detects an OTG
  90 *              test device. This must be set by host/hub driver
  91 *
  92 *      Application inputs (A-Device)
  93 * @a_bus_drop: TRUE when A-device application needs to power down the bus
  94 * @a_bus_req:  TRUE when A-device application wants to use the bus.
  95 *              FALSE to suspend the bus
  96 *
  97 *      Application inputs (B-Device)
  98 * @b_bus_req:  TRUE during the time that the Application running on the
  99 *              B-device wants to use the bus
 100 *
 101 *      Auxiliary inputs (OTG v1.3 only. Obsolete now.)
 102 * @a_sess_vld: TRUE if the A-device detects that VBUS is above VA_SESS_VLD
 103 * @b_bus_suspend: TRUE when the A-device detects that the B-device has put
 104 *              the bus into suspend
 105 * @b_bus_resume: TRUE when the A-device detects that the B-device is signaling
 106 *               resume on the bus
 107 *
 108 * OTG Output status. Read only for users. Updated by OTG FSM helpers defined
 109 * in this file
 110 *
 111 *      Outputs for Both A and B device
 112 * @drv_vbus:   TRUE when A-device is driving VBUS
 113 * @loc_conn:   TRUE when the local device has signaled that it is connected
 114 *              to the bus
 115 * @loc_sof:    TRUE when the local device is generating activity on the bus
 116 * @adp_prb:    TRUE when the local device is in the process of doing
 117 *              ADP probing
 118 *
 119 *      Outputs for B-device state
 120 * @adp_sns:    TRUE when the B-device is in the process of carrying out
 121 *              ADP sensing
 122 * @data_pulse: TRUE when the B-device is performing data line pulsing
 123 *
 124 * Internal Variables
 125 *
 126 * a_set_b_hnp_en: TRUE when the A-device has successfully set the
 127 *              b_hnp_enable bit in the B-device.
 128 *                 Unused as OTG fsm uses otg->host->b_hnp_enable instead
 129 * b_srp_done:  TRUE when the B-device has completed initiating SRP
 130 * b_hnp_enable: TRUE when the B-device has accepted the
 131 *              SetFeature(b_hnp_enable) B-device.
 132 *              Unused as OTG fsm uses otg->gadget->b_hnp_enable instead
 133 * a_clr_err:   Asserted (by application ?) to clear a_vbus_err due to an
 134 *              overcurrent condition and causes the A-device to transition
 135 *              to a_wait_vfall
 136 */
 137struct otg_fsm {
 138        /* Input */
 139        int id;
 140        int adp_change;
 141        int power_up;
 142        int a_srp_det;
 143        int a_vbus_vld;
 144        int b_conn;
 145        int a_bus_resume;
 146        int a_bus_suspend;
 147        int a_conn;
 148        int b_se0_srp;
 149        int b_ssend_srp;
 150        int b_sess_vld;
 151        int test_device;
 152        int a_bus_drop;
 153        int a_bus_req;
 154        int b_bus_req;
 155
 156        /* Auxiliary inputs */
 157        int a_sess_vld;
 158        int b_bus_resume;
 159        int b_bus_suspend;
 160
 161        /* Output */
 162        int drv_vbus;
 163        int loc_conn;
 164        int loc_sof;
 165        int adp_prb;
 166        int adp_sns;
 167        int data_pulse;
 168
 169        /* Internal variables */
 170        int a_set_b_hnp_en;
 171        int b_srp_done;
 172        int b_hnp_enable;
 173        int a_clr_err;
 174
 175        /* Informative variables. All unused as of now */
 176        int a_bus_drop_inf;
 177        int a_bus_req_inf;
 178        int a_clr_err_inf;
 179        int b_bus_req_inf;
 180        /* Auxiliary informative variables */
 181        int a_suspend_req_inf;
 182
 183        /* Timeout indicator for timers */
 184        int a_wait_vrise_tmout;
 185        int a_wait_vfall_tmout;
 186        int a_wait_bcon_tmout;
 187        int a_aidl_bdis_tmout;
 188        int b_ase0_brst_tmout;
 189        int a_bidl_adis_tmout;
 190
 191        struct otg_fsm_ops *ops;
 192        struct usb_otg *otg;
 193
 194        /* Current usb protocol used: 0:undefine; 1:host; 2:client */
 195        int protocol;
 196        struct mutex lock;
 197        u8 *host_req_flag;
 198        struct delayed_work hnp_polling_work;
 199        bool hnp_work_inited;
 200        bool state_changed;
 201};
 202
 203struct otg_fsm_ops {
 204        void    (*chrg_vbus)(struct otg_fsm *fsm, int on);
 205        void    (*drv_vbus)(struct otg_fsm *fsm, int on);
 206        void    (*loc_conn)(struct otg_fsm *fsm, int on);
 207        void    (*loc_sof)(struct otg_fsm *fsm, int on);
 208        void    (*start_pulse)(struct otg_fsm *fsm);
 209        void    (*start_adp_prb)(struct otg_fsm *fsm);
 210        void    (*start_adp_sns)(struct otg_fsm *fsm);
 211        void    (*add_timer)(struct otg_fsm *fsm, enum otg_fsm_timer timer);
 212        void    (*del_timer)(struct otg_fsm *fsm, enum otg_fsm_timer timer);
 213        int     (*start_host)(struct otg_fsm *fsm, int on);
 214        int     (*start_gadget)(struct otg_fsm *fsm, int on);
 215};
 216
 217
 218static inline int otg_chrg_vbus(struct otg_fsm *fsm, int on)
 219{
 220        if (!fsm->ops->chrg_vbus)
 221                return -EOPNOTSUPP;
 222        fsm->ops->chrg_vbus(fsm, on);
 223        return 0;
 224}
 225
 226static inline int otg_drv_vbus(struct otg_fsm *fsm, int on)
 227{
 228        if (!fsm->ops->drv_vbus)
 229                return -EOPNOTSUPP;
 230        if (fsm->drv_vbus != on) {
 231                fsm->drv_vbus = on;
 232                fsm->ops->drv_vbus(fsm, on);
 233        }
 234        return 0;
 235}
 236
 237static inline int otg_loc_conn(struct otg_fsm *fsm, int on)
 238{
 239        if (!fsm->ops->loc_conn)
 240                return -EOPNOTSUPP;
 241        if (fsm->loc_conn != on) {
 242                fsm->loc_conn = on;
 243                fsm->ops->loc_conn(fsm, on);
 244        }
 245        return 0;
 246}
 247
 248static inline int otg_loc_sof(struct otg_fsm *fsm, int on)
 249{
 250        if (!fsm->ops->loc_sof)
 251                return -EOPNOTSUPP;
 252        if (fsm->loc_sof != on) {
 253                fsm->loc_sof = on;
 254                fsm->ops->loc_sof(fsm, on);
 255        }
 256        return 0;
 257}
 258
 259static inline int otg_start_pulse(struct otg_fsm *fsm)
 260{
 261        if (!fsm->ops->start_pulse)
 262                return -EOPNOTSUPP;
 263        if (!fsm->data_pulse) {
 264                fsm->data_pulse = 1;
 265                fsm->ops->start_pulse(fsm);
 266        }
 267        return 0;
 268}
 269
 270static inline int otg_start_adp_prb(struct otg_fsm *fsm)
 271{
 272        if (!fsm->ops->start_adp_prb)
 273                return -EOPNOTSUPP;
 274        if (!fsm->adp_prb) {
 275                fsm->adp_sns = 0;
 276                fsm->adp_prb = 1;
 277                fsm->ops->start_adp_prb(fsm);
 278        }
 279        return 0;
 280}
 281
 282static inline int otg_start_adp_sns(struct otg_fsm *fsm)
 283{
 284        if (!fsm->ops->start_adp_sns)
 285                return -EOPNOTSUPP;
 286        if (!fsm->adp_sns) {
 287                fsm->adp_sns = 1;
 288                fsm->ops->start_adp_sns(fsm);
 289        }
 290        return 0;
 291}
 292
 293static inline int otg_add_timer(struct otg_fsm *fsm, enum otg_fsm_timer timer)
 294{
 295        if (!fsm->ops->add_timer)
 296                return -EOPNOTSUPP;
 297        fsm->ops->add_timer(fsm, timer);
 298        return 0;
 299}
 300
 301static inline int otg_del_timer(struct otg_fsm *fsm, enum otg_fsm_timer timer)
 302{
 303        if (!fsm->ops->del_timer)
 304                return -EOPNOTSUPP;
 305        fsm->ops->del_timer(fsm, timer);
 306        return 0;
 307}
 308
 309static inline int otg_start_host(struct otg_fsm *fsm, int on)
 310{
 311        if (!fsm->ops->start_host)
 312                return -EOPNOTSUPP;
 313        return fsm->ops->start_host(fsm, on);
 314}
 315
 316static inline int otg_start_gadget(struct otg_fsm *fsm, int on)
 317{
 318        if (!fsm->ops->start_gadget)
 319                return -EOPNOTSUPP;
 320        return fsm->ops->start_gadget(fsm, on);
 321}
 322
 323int otg_statemachine(struct otg_fsm *fsm);
 324
 325#endif /* __LINUX_USB_OTG_FSM_H */
 326