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
  41 enum 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  *      Auxilary 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  */
 137 struct 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         /* Auxilary 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         /* Auxilary 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 state_changed;
 200 };
 201
 202 struct otg_fsm_ops {
 203         void    (*chrg_vbus)(struct otg_fsm *fsm, int on);
 204         void    (*drv_vbus)(struct otg_fsm *fsm, int on);
 205         void    (*loc_conn)(struct otg_fsm *fsm, int on);
 206         void    (*loc_sof)(struct otg_fsm *fsm, int on);
 207         void    (*start_pulse)(struct otg_fsm *fsm);
 208         void    (*start_adp_prb)(struct otg_fsm *fsm);
 209         void    (*start_adp_sns)(struct otg_fsm *fsm);
 210         void    (*add_timer)(struct otg_fsm *fsm, enum otg_fsm_timer timer);
 211         void    (*del_timer)(struct otg_fsm *fsm, enum otg_fsm_timer timer);
 212         int     (*start_host)(struct otg_fsm *fsm, int on);
 213         int     (*start_gadget)(struct otg_fsm *fsm, int on);
 214 };
 215
 216
 217 static inline int otg_chrg_vbus(struct otg_fsm *fsm, int on)
 218 {
 219         if (!fsm->ops->chrg_vbus)
 220                 return -EOPNOTSUPP;
 221         fsm->ops->chrg_vbus(fsm, on);
 222         return 0;
 223 }
 224
 225 static inline int otg_drv_vbus(struct otg_fsm *fsm, int on)
 226 {
 227         if (!fsm->ops->drv_vbus)
 228                 return -EOPNOTSUPP;
 229         if (fsm->drv_vbus != on) {
 230                 fsm->drv_vbus = on;
 231                 fsm->ops->drv_vbus(fsm, on);
 232         }
 233         return 0;
 234 }
 235
 236 static inline int otg_loc_conn(struct otg_fsm *fsm, int on)
 237 {
 238         if (!fsm->ops->loc_conn)
 239                 return -EOPNOTSUPP;
 240         if (fsm->loc_conn != on) {
 241                 fsm->loc_conn = on;
 242                 fsm->ops->loc_conn(fsm, on);
 243         }
 244         return 0;
 245 }
 246
 247 static inline int otg_loc_sof(struct otg_fsm *fsm, int on)
 248 {
 249         if (!fsm->ops->loc_sof)
 250                 return -EOPNOTSUPP;
 251         if (fsm->loc_sof != on) {
 252                 fsm->loc_sof = on;
 253                 fsm->ops->loc_sof(fsm, on);
 254         }
 255         return 0;
 256 }
 257
 258 static inline int otg_start_pulse(struct otg_fsm *fsm)
 259 {
 260         if (!fsm->ops->start_pulse)
 261                 return -EOPNOTSUPP;
 262         if (!fsm->data_pulse) {
 263                 fsm->data_pulse = 1;
 264                 fsm->ops->start_pulse(fsm);
 265         }
 266         return 0;
 267 }
 268
 269 static inline int otg_start_adp_prb(struct otg_fsm *fsm)
 270 {
 271         if (!fsm->ops->start_adp_prb)
 272                 return -EOPNOTSUPP;
 273         if (!fsm->adp_prb) {
 274                 fsm->adp_sns = 0;
 275                 fsm->adp_prb = 1;
 276                 fsm->ops->start_adp_prb(fsm);
 277         }
 278         return 0;
 279 }
 280
 281 static inline int otg_start_adp_sns(struct otg_fsm *fsm)
 282 {
 283         if (!fsm->ops->start_adp_sns)
 284                 return -EOPNOTSUPP;
 285         if (!fsm->adp_sns) {
 286                 fsm->adp_sns = 1;
 287                 fsm->ops->start_adp_sns(fsm);
 288         }
 289         return 0;
 290 }
 291
 292 static inline int otg_add_timer(struct otg_fsm *fsm, enum otg_fsm_timer timer)
 293 {
 294         if (!fsm->ops->add_timer)
 295                 return -EOPNOTSUPP;
 296         fsm->ops->add_timer(fsm, timer);
 297         return 0;
 298 }
 299
 300 static inline int otg_del_timer(struct otg_fsm *fsm, enum otg_fsm_timer timer)
 301 {
 302         if (!fsm->ops->del_timer)
 303                 return -EOPNOTSUPP;
 304         fsm->ops->del_timer(fsm, timer);
 305         return 0;
 306 }
 307
 308 static inline int otg_start_host(struct otg_fsm *fsm, int on)
 309 {
 310         if (!fsm->ops->start_host)
 311                 return -EOPNOTSUPP;
 312         return fsm->ops->start_host(fsm, on);
 313 }
 314
 315 static inline int otg_start_gadget(struct otg_fsm *fsm, int on)
 316 {
 317         if (!fsm->ops->start_gadget)
 318                 return -EOPNOTSUPP;
 319         return fsm->ops->start_gadget(fsm, on);
 320 }
 321
 322 int otg_statemachine(struct otg_fsm *fsm);
 323
 324 #endif /* __LINUX_USB_OTG_FSM_H */