include/linux/usb/otg-fsm.h

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