drivers/usb/chipidea/otg_fsm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * otg_fsm.c - ChipIdea USB IP core OTG FSM driver
   4  *
   5  * Copyright (C) 2014 Freescale Semiconductor, Inc.
   6  *
   7  * Author: Jun Li
   8  */
   9
  10 /*
  11  * This file mainly handles OTG fsm, it includes OTG fsm operations
  12  * for HNP and SRP.
  13  *
  14  * TODO List
  15  * - ADP
  16  * - OTG test device
  17  */
  18
  19 #include <linux/usb/otg.h>
  20 #include <linux/usb/gadget.h>
  21 #include <linux/usb/hcd.h>
  22 #include <linux/usb/chipidea.h>
  23 #include <linux/regulator/consumer.h>
  24
  25 #include "ci.h"
  26 #include "bits.h"
  27 #include "otg.h"
  28 #include "otg_fsm.h"
  29
  30 /* Add for otg: interact with user space app */
  31 static ssize_t
  32 a_bus_req_show(struct device *dev, struct device_attribute *attr, char *buf)
  33 {
  34         char            *next;
  35         unsigned        size, t;
  36         struct ci_hdrc  *ci = dev_get_drvdata(dev);
  37
  38         next = buf;
  39         size = PAGE_SIZE;
  40         t = scnprintf(next, size, "%d\n", ci->fsm.a_bus_req);
  41         size -= t;
  42         next += t;
  43
  44         return PAGE_SIZE - size;
  45 }
  46
  47 static ssize_t
  48 a_bus_req_store(struct device *dev, struct device_attribute *attr,
  49                                         const char *buf, size_t count)
  50 {
  51         struct ci_hdrc *ci = dev_get_drvdata(dev);
  52
  53         if (count > 2)
  54                 return -1;
  55
  56         mutex_lock(&ci->fsm.lock);
  57         if (buf[0] == '0') {
  58                 ci->fsm.a_bus_req = 0;
  59         } else if (buf[0] == '1') {
  60                 /* If a_bus_drop is TRUE, a_bus_req can't be set */
  61                 if (ci->fsm.a_bus_drop) {
  62                         mutex_unlock(&ci->fsm.lock);
  63                         return count;
  64                 }
  65                 ci->fsm.a_bus_req = 1;
  66                 if (ci->fsm.otg->state == OTG_STATE_A_PERIPHERAL) {
  67                         ci->gadget.host_request_flag = 1;
  68                         mutex_unlock(&ci->fsm.lock);
  69                         return count;
  70                 }
  71         }
  72
  73         ci_otg_queue_work(ci);
  74         mutex_unlock(&ci->fsm.lock);
  75
  76         return count;
  77 }
  78 static DEVICE_ATTR_RW(a_bus_req);
  79
  80 static ssize_t
  81 a_bus_drop_show(struct device *dev, struct device_attribute *attr, char *buf)
  82 {
  83         char            *next;
  84         unsigned        size, t;
  85         struct ci_hdrc  *ci = dev_get_drvdata(dev);
  86
  87         next = buf;
  88         size = PAGE_SIZE;
  89         t = scnprintf(next, size, "%d\n", ci->fsm.a_bus_drop);
  90         size -= t;
  91         next += t;
  92
  93         return PAGE_SIZE - size;
  94 }
  95
  96 static ssize_t
  97 a_bus_drop_store(struct device *dev, struct device_attribute *attr,
  98                                         const char *buf, size_t count)
  99 {
 100         struct ci_hdrc  *ci = dev_get_drvdata(dev);
 101
 102         if (count > 2)
 103                 return -1;
 104
 105         mutex_lock(&ci->fsm.lock);
 106         if (buf[0] == '0') {
 107                 ci->fsm.a_bus_drop = 0;
 108         } else if (buf[0] == '1') {
 109                 ci->fsm.a_bus_drop = 1;
 110                 ci->fsm.a_bus_req = 0;
 111         }
 112
 113         ci_otg_queue_work(ci);
 114         mutex_unlock(&ci->fsm.lock);
 115
 116         return count;
 117 }
 118 static DEVICE_ATTR_RW(a_bus_drop);
 119
 120 static ssize_t
 121 b_bus_req_show(struct device *dev, struct device_attribute *attr, char *buf)
 122 {
 123         char            *next;
 124         unsigned        size, t;
 125         struct ci_hdrc  *ci = dev_get_drvdata(dev);
 126
 127         next = buf;
 128         size = PAGE_SIZE;
 129         t = scnprintf(next, size, "%d\n", ci->fsm.b_bus_req);
 130         size -= t;
 131         next += t;
 132
 133         return PAGE_SIZE - size;
 134 }
 135
 136 static ssize_t
 137 b_bus_req_store(struct device *dev, struct device_attribute *attr,
 138                                         const char *buf, size_t count)
 139 {
 140         struct ci_hdrc  *ci = dev_get_drvdata(dev);
 141
 142         if (count > 2)
 143                 return -1;
 144
 145         mutex_lock(&ci->fsm.lock);
 146         if (buf[0] == '0')
 147                 ci->fsm.b_bus_req = 0;
 148         else if (buf[0] == '1') {
 149                 ci->fsm.b_bus_req = 1;
 150                 if (ci->fsm.otg->state == OTG_STATE_B_PERIPHERAL) {
 151                         ci->gadget.host_request_flag = 1;
 152                         mutex_unlock(&ci->fsm.lock);
 153                         return count;
 154                 }
 155         }
 156
 157         ci_otg_queue_work(ci);
 158         mutex_unlock(&ci->fsm.lock);
 159
 160         return count;
 161 }
 162 static DEVICE_ATTR_RW(b_bus_req);
 163
 164 static ssize_t
 165 a_clr_err_store(struct device *dev, struct device_attribute *attr,
 166                                         const char *buf, size_t count)
 167 {
 168         struct ci_hdrc  *ci = dev_get_drvdata(dev);
 169
 170         if (count > 2)
 171                 return -1;
 172
 173         mutex_lock(&ci->fsm.lock);
 174         if (buf[0] == '1')
 175                 ci->fsm.a_clr_err = 1;
 176
 177         ci_otg_queue_work(ci);
 178         mutex_unlock(&ci->fsm.lock);
 179
 180         return count;
 181 }
 182 static DEVICE_ATTR_WO(a_clr_err);
 183
 184 static struct attribute *inputs_attrs[] = {
 185         &dev_attr_a_bus_req.attr,
 186         &dev_attr_a_bus_drop.attr,
 187         &dev_attr_b_bus_req.attr,
 188         &dev_attr_a_clr_err.attr,
 189         NULL,
 190 };
 191
 192 static const struct attribute_group inputs_attr_group = {
 193         .name = "inputs",
 194         .attrs = inputs_attrs,
 195 };
 196
 197 /*
 198  * Keep this list in the same order as timers indexed
 199  * by enum otg_fsm_timer in include/linux/usb/otg-fsm.h
 200  */
 201 static unsigned otg_timer_ms[] = {
 202         TA_WAIT_VRISE,
 203         TA_WAIT_VFALL,
 204         TA_WAIT_BCON,
 205         TA_AIDL_BDIS,
 206         TB_ASE0_BRST,
 207         TA_BIDL_ADIS,
 208         TB_AIDL_BDIS,
 209         TB_SE0_SRP,
 210         TB_SRP_FAIL,
 211         0,
 212         TB_DATA_PLS,
 213         TB_SSEND_SRP,
 214 };
 215
 216 /*
 217  * Add timer to active timer list
 218  */
 219 static void ci_otg_add_timer(struct ci_hdrc *ci, enum otg_fsm_timer t)
 220 {
 221         unsigned long flags, timer_sec, timer_nsec;
 222
 223         if (t >= NUM_OTG_FSM_TIMERS)
 224                 return;
 225
 226         spin_lock_irqsave(&ci->lock, flags);
 227         timer_sec = otg_timer_ms[t] / MSEC_PER_SEC;
 228         timer_nsec = (otg_timer_ms[t] % MSEC_PER_SEC) * NSEC_PER_MSEC;
 229         ci->hr_timeouts[t] = ktime_add(ktime_get(),
 230                                 ktime_set(timer_sec, timer_nsec));
 231         ci->enabled_otg_timer_bits |= (1 << t);
 232         if ((ci->next_otg_timer == NUM_OTG_FSM_TIMERS) ||
 233                         ktime_after(ci->hr_timeouts[ci->next_otg_timer],
 234                                                 ci->hr_timeouts[t])) {
 235                         ci->next_otg_timer = t;
 236                         hrtimer_start_range_ns(&ci->otg_fsm_hrtimer,
 237                                         ci->hr_timeouts[t], NSEC_PER_MSEC,
 238                                                         HRTIMER_MODE_ABS);
 239         }
 240         spin_unlock_irqrestore(&ci->lock, flags);
 241 }
 242
 243 /*
 244  * Remove timer from active timer list
 245  */
 246 static void ci_otg_del_timer(struct ci_hdrc *ci, enum otg_fsm_timer t)
 247 {
 248         unsigned long flags, enabled_timer_bits;
 249         enum otg_fsm_timer cur_timer, next_timer = NUM_OTG_FSM_TIMERS;
 250
 251         if ((t >= NUM_OTG_FSM_TIMERS) ||
 252                         !(ci->enabled_otg_timer_bits & (1 << t)))
 253                 return;
 254
 255         spin_lock_irqsave(&ci->lock, flags);
 256         ci->enabled_otg_timer_bits &= ~(1 << t);
 257         if (ci->next_otg_timer == t) {
 258                 if (ci->enabled_otg_timer_bits == 0) {
 259                         /* No enabled timers after delete it */
 260                         hrtimer_cancel(&ci->otg_fsm_hrtimer);
 261                         ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
 262                 } else {
 263                         /* Find the next timer */
 264                         enabled_timer_bits = ci->enabled_otg_timer_bits;
 265                         for_each_set_bit(cur_timer, &enabled_timer_bits,
 266                                                         NUM_OTG_FSM_TIMERS) {
 267                                 if ((next_timer == NUM_OTG_FSM_TIMERS) ||
 268                                         ktime_before(ci->hr_timeouts[next_timer],
 269                                          ci->hr_timeouts[cur_timer]))
 270                                         next_timer = cur_timer;
 271                         }
 272                 }
 273         }
 274         if (next_timer != NUM_OTG_FSM_TIMERS) {
 275                 ci->next_otg_timer = next_timer;
 276                 hrtimer_start_range_ns(&ci->otg_fsm_hrtimer,
 277                         ci->hr_timeouts[next_timer], NSEC_PER_MSEC,
 278                                                         HRTIMER_MODE_ABS);
 279         }
 280         spin_unlock_irqrestore(&ci->lock, flags);
 281 }
 282
 283 /* OTG FSM timer handlers */
 284 static int a_wait_vrise_tmout(struct ci_hdrc *ci)
 285 {
 286         ci->fsm.a_wait_vrise_tmout = 1;
 287         return 0;
 288 }
 289
 290 static int a_wait_vfall_tmout(struct ci_hdrc *ci)
 291 {
 292         ci->fsm.a_wait_vfall_tmout = 1;
 293         return 0;
 294 }
 295
 296 static int a_wait_bcon_tmout(struct ci_hdrc *ci)
 297 {
 298         ci->fsm.a_wait_bcon_tmout = 1;
 299         return 0;
 300 }
 301
 302 static int a_aidl_bdis_tmout(struct ci_hdrc *ci)
 303 {
 304         ci->fsm.a_aidl_bdis_tmout = 1;
 305         return 0;
 306 }
 307
 308 static int b_ase0_brst_tmout(struct ci_hdrc *ci)
 309 {
 310         ci->fsm.b_ase0_brst_tmout = 1;
 311         return 0;
 312 }
 313
 314 static int a_bidl_adis_tmout(struct ci_hdrc *ci)
 315 {
 316         ci->fsm.a_bidl_adis_tmout = 1;
 317         return 0;
 318 }
 319
 320 static int b_aidl_bdis_tmout(struct ci_hdrc *ci)
 321 {
 322         ci->fsm.a_bus_suspend = 1;
 323         return 0;
 324 }
 325
 326 static int b_se0_srp_tmout(struct ci_hdrc *ci)
 327 {
 328         ci->fsm.b_se0_srp = 1;
 329         return 0;
 330 }
 331
 332 static int b_srp_fail_tmout(struct ci_hdrc *ci)
 333 {
 334         ci->fsm.b_srp_done = 1;
 335         return 1;
 336 }
 337
 338 static int b_data_pls_tmout(struct ci_hdrc *ci)
 339 {
 340         ci->fsm.b_srp_done = 1;
 341         ci->fsm.b_bus_req = 0;
 342         if (ci->fsm.power_up)
 343                 ci->fsm.power_up = 0;
 344         hw_write_otgsc(ci, OTGSC_HABA, 0);
 345         pm_runtime_put(ci->dev);
 346         return 0;
 347 }
 348
 349 static int b_ssend_srp_tmout(struct ci_hdrc *ci)
 350 {
 351         ci->fsm.b_ssend_srp = 1;
 352         /* only vbus fall below B_sess_vld in b_idle state */
 353         if (ci->fsm.otg->state == OTG_STATE_B_IDLE)
 354                 return 0;
 355         else
 356                 return 1;
 357 }
 358
 359 /*
 360  * Keep this list in the same order as timers indexed
 361  * by enum otg_fsm_timer in include/linux/usb/otg-fsm.h
 362  */
 363 static int (*otg_timer_handlers[])(struct ci_hdrc *) = {
 364         a_wait_vrise_tmout,     /* A_WAIT_VRISE */
 365         a_wait_vfall_tmout,     /* A_WAIT_VFALL */
 366         a_wait_bcon_tmout,      /* A_WAIT_BCON */
 367         a_aidl_bdis_tmout,      /* A_AIDL_BDIS */
 368         b_ase0_brst_tmout,      /* B_ASE0_BRST */
 369         a_bidl_adis_tmout,      /* A_BIDL_ADIS */
 370         b_aidl_bdis_tmout,      /* B_AIDL_BDIS */
 371         b_se0_srp_tmout,        /* B_SE0_SRP */
 372         b_srp_fail_tmout,       /* B_SRP_FAIL */
 373         NULL,                   /* A_WAIT_ENUM */
 374         b_data_pls_tmout,       /* B_DATA_PLS */
 375         b_ssend_srp_tmout,      /* B_SSEND_SRP */
 376 };
 377
 378 /*
 379  * Enable the next nearest enabled timer if have
 380  */
 381 static enum hrtimer_restart ci_otg_hrtimer_func(struct hrtimer *t)
 382 {
 383         struct ci_hdrc *ci = container_of(t, struct ci_hdrc, otg_fsm_hrtimer);
 384         ktime_t now, *timeout;
 385         unsigned long   enabled_timer_bits;
 386         unsigned long   flags;
 387         enum otg_fsm_timer cur_timer, next_timer = NUM_OTG_FSM_TIMERS;
 388         int ret = -EINVAL;
 389
 390         spin_lock_irqsave(&ci->lock, flags);
 391         enabled_timer_bits = ci->enabled_otg_timer_bits;
 392         ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
 393
 394         now = ktime_get();
 395         for_each_set_bit(cur_timer, &enabled_timer_bits, NUM_OTG_FSM_TIMERS) {
 396                 if (ktime_compare(now, ci->hr_timeouts[cur_timer]) >= 0) {
 397                         ci->enabled_otg_timer_bits &= ~(1 << cur_timer);
 398                         if (otg_timer_handlers[cur_timer])
 399                                 ret = otg_timer_handlers[cur_timer](ci);
 400                 } else {
 401                         if ((next_timer == NUM_OTG_FSM_TIMERS) ||
 402                                 ktime_before(ci->hr_timeouts[cur_timer],
 403                                         ci->hr_timeouts[next_timer]))
 404                                 next_timer = cur_timer;
 405                 }
 406         }
 407         /* Enable the next nearest timer */
 408         if (next_timer < NUM_OTG_FSM_TIMERS) {
 409                 timeout = &ci->hr_timeouts[next_timer];
 410                 hrtimer_start_range_ns(&ci->otg_fsm_hrtimer, *timeout,
 411                                         NSEC_PER_MSEC, HRTIMER_MODE_ABS);
 412                 ci->next_otg_timer = next_timer;
 413         }
 414         spin_unlock_irqrestore(&ci->lock, flags);
 415
 416         if (!ret)
 417                 ci_otg_queue_work(ci);
 418
 419         return HRTIMER_NORESTART;
 420 }
 421
 422 /* Initialize timers */
 423 static int ci_otg_init_timers(struct ci_hdrc *ci)
 424 {
 425         hrtimer_init(&ci->otg_fsm_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 426         ci->otg_fsm_hrtimer.function = ci_otg_hrtimer_func;
 427
 428         return 0;
 429 }
 430
 431 /* -------------------------------------------------------------*/
 432 /* Operations that will be called from OTG Finite State Machine */
 433 /* -------------------------------------------------------------*/
 434 static void ci_otg_fsm_add_timer(struct otg_fsm *fsm, enum otg_fsm_timer t)
 435 {
 436         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 437
 438         if (t < NUM_OTG_FSM_TIMERS)
 439                 ci_otg_add_timer(ci, t);
 440         return;
 441 }
 442
 443 static void ci_otg_fsm_del_timer(struct otg_fsm *fsm, enum otg_fsm_timer t)
 444 {
 445         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 446
 447         if (t < NUM_OTG_FSM_TIMERS)
 448                 ci_otg_del_timer(ci, t);
 449         return;
 450 }
 451
 452 /*
 453  * A-device drive vbus: turn on vbus regulator and enable port power
 454  * Data pulse irq should be disabled while vbus is on.
 455  */
 456 static void ci_otg_drv_vbus(struct otg_fsm *fsm, int on)
 457 {
 458         int ret;
 459         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 460
 461         if (on) {
 462                 /* Enable power */
 463                 hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS | PORTSC_PP,
 464                                                         PORTSC_PP);
 465                 if (ci->platdata->reg_vbus) {
 466                         ret = regulator_enable(ci->platdata->reg_vbus);
 467                         if (ret) {
 468                                 dev_err(ci->dev,
 469                                 "Failed to enable vbus regulator, ret=%d\n",
 470                                 ret);
 471                                 return;
 472                         }
 473                 }
 474                 /* Disable data pulse irq */
 475                 hw_write_otgsc(ci, OTGSC_DPIE, 0);
 476
 477                 fsm->a_srp_det = 0;
 478                 fsm->power_up = 0;
 479         } else {
 480                 if (ci->platdata->reg_vbus)
 481                         regulator_disable(ci->platdata->reg_vbus);
 482
 483                 fsm->a_bus_drop = 1;
 484                 fsm->a_bus_req = 0;
 485         }
 486 }
 487
 488 /*
 489  * Control data line by Run Stop bit.
 490  */
 491 static void ci_otg_loc_conn(struct otg_fsm *fsm, int on)
 492 {
 493         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 494
 495         if (on)
 496                 hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
 497         else
 498                 hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
 499 }
 500
 501 /*
 502  * Generate SOF by host.
 503  * In host mode, controller will automatically send SOF.
 504  * Suspend will block the data on the port.
 505  *
 506  * This is controlled through usbcore by usb autosuspend,
 507  * so the usb device class driver need support autosuspend,
 508  * otherwise the bus suspend will not happen.
 509  */
 510 static void ci_otg_loc_sof(struct otg_fsm *fsm, int on)
 511 {
 512         struct usb_device *udev;
 513
 514         if (!fsm->otg->host)
 515                 return;
 516
 517         udev = usb_hub_find_child(fsm->otg->host->root_hub, 1);
 518         if (!udev)
 519                 return;
 520
 521         if (on) {
 522                 usb_disable_autosuspend(udev);
 523         } else {
 524                 pm_runtime_set_autosuspend_delay(&udev->dev, 0);
 525                 usb_enable_autosuspend(udev);
 526         }
 527 }
 528
 529 /*
 530  * Start SRP pulsing by data-line pulsing,
 531  * no v-bus pulsing followed
 532  */
 533 static void ci_otg_start_pulse(struct otg_fsm *fsm)
 534 {
 535         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 536
 537         /* Hardware Assistant Data pulse */
 538         hw_write_otgsc(ci, OTGSC_HADP, OTGSC_HADP);
 539
 540         pm_runtime_get(ci->dev);
 541         ci_otg_add_timer(ci, B_DATA_PLS);
 542 }
 543
 544 static int ci_otg_start_host(struct otg_fsm *fsm, int on)
 545 {
 546         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 547
 548         if (on) {
 549                 ci_role_stop(ci);
 550                 ci_role_start(ci, CI_ROLE_HOST);
 551         } else {
 552                 ci_role_stop(ci);
 553                 ci_role_start(ci, CI_ROLE_GADGET);
 554         }
 555         return 0;
 556 }
 557
 558 static int ci_otg_start_gadget(struct otg_fsm *fsm, int on)
 559 {
 560         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 561
 562         if (on)
 563                 usb_gadget_vbus_connect(&ci->gadget);
 564         else
 565                 usb_gadget_vbus_disconnect(&ci->gadget);
 566
 567         return 0;
 568 }
 569
 570 static struct otg_fsm_ops ci_otg_ops = {
 571         .drv_vbus = ci_otg_drv_vbus,
 572         .loc_conn = ci_otg_loc_conn,
 573         .loc_sof = ci_otg_loc_sof,
 574         .start_pulse = ci_otg_start_pulse,
 575         .add_timer = ci_otg_fsm_add_timer,
 576         .del_timer = ci_otg_fsm_del_timer,
 577         .start_host = ci_otg_start_host,
 578         .start_gadget = ci_otg_start_gadget,
 579 };
 580
 581 int ci_otg_fsm_work(struct ci_hdrc *ci)
 582 {
 583         /*
 584          * Don't do fsm transition for B device
 585          * when there is no gadget class driver
 586          */
 587         if (ci->fsm.id && !(ci->driver) &&
 588                 ci->fsm.otg->state < OTG_STATE_A_IDLE)
 589                 return 0;
 590
 591         pm_runtime_get_sync(ci->dev);
 592         if (otg_statemachine(&ci->fsm)) {
 593                 if (ci->fsm.otg->state == OTG_STATE_A_IDLE) {
 594                         /*
 595                          * Further state change for cases:
 596                          * a_idle to b_idle; or
 597                          * a_idle to a_wait_vrise due to ID change(1->0), so
 598                          * B-dev becomes A-dev can try to start new session
 599                          * consequently; or
 600                          * a_idle to a_wait_vrise when power up
 601                          */
 602                         if ((ci->fsm.id) || (ci->id_event) ||
 603                                                 (ci->fsm.power_up)) {
 604                                 ci_otg_queue_work(ci);
 605                         } else {
 606                                 /* Enable data pulse irq */
 607                                 hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS |
 608                                                                 PORTSC_PP, 0);
 609                                 hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
 610                                 hw_write_otgsc(ci, OTGSC_DPIE, OTGSC_DPIE);
 611                         }
 612                         if (ci->id_event)
 613                                 ci->id_event = false;
 614                 } else if (ci->fsm.otg->state == OTG_STATE_B_IDLE) {
 615                         if (ci->fsm.b_sess_vld) {
 616                                 ci->fsm.power_up = 0;
 617                                 /*
 618                                  * Further transite to b_periphearl state
 619                                  * when register gadget driver with vbus on
 620                                  */
 621                                 ci_otg_queue_work(ci);
 622                         }
 623                 } else if (ci->fsm.otg->state == OTG_STATE_A_HOST) {
 624                         pm_runtime_mark_last_busy(ci->dev);
 625                         pm_runtime_put_autosuspend(ci->dev);
 626                         return 0;
 627                 }
 628         }
 629         pm_runtime_put_sync(ci->dev);
 630         return 0;
 631 }
 632
 633 /*
 634  * Update fsm variables in each state if catching expected interrupts,
 635  * called by otg fsm isr.
 636  */
 637 static void ci_otg_fsm_event(struct ci_hdrc *ci)
 638 {
 639         u32 intr_sts, otg_bsess_vld, port_conn;
 640         struct otg_fsm *fsm = &ci->fsm;
 641
 642         intr_sts = hw_read_intr_status(ci);
 643         otg_bsess_vld = hw_read_otgsc(ci, OTGSC_BSV);
 644         port_conn = hw_read(ci, OP_PORTSC, PORTSC_CCS);
 645
 646         switch (ci->fsm.otg->state) {
 647         case OTG_STATE_A_WAIT_BCON:
 648                 if (port_conn) {
 649                         fsm->b_conn = 1;
 650                         fsm->a_bus_req = 1;
 651                         ci_otg_queue_work(ci);
 652                 }
 653                 break;
 654         case OTG_STATE_B_IDLE:
 655                 if (otg_bsess_vld && (intr_sts & USBi_PCI) && port_conn) {
 656                         fsm->b_sess_vld = 1;
 657                         ci_otg_queue_work(ci);
 658                 }
 659                 break;
 660         case OTG_STATE_B_PERIPHERAL:
 661                 if ((intr_sts & USBi_SLI) && port_conn && otg_bsess_vld) {
 662                         ci_otg_add_timer(ci, B_AIDL_BDIS);
 663                 } else if (intr_sts & USBi_PCI) {
 664                         ci_otg_del_timer(ci, B_AIDL_BDIS);
 665                         if (fsm->a_bus_suspend == 1)
 666                                 fsm->a_bus_suspend = 0;
 667                 }
 668                 break;
 669         case OTG_STATE_B_HOST:
 670                 if ((intr_sts & USBi_PCI) && !port_conn) {
 671                         fsm->a_conn = 0;
 672                         fsm->b_bus_req = 0;
 673                         ci_otg_queue_work(ci);
 674                 }
 675                 break;
 676         case OTG_STATE_A_PERIPHERAL:
 677                 if (intr_sts & USBi_SLI) {
 678                          fsm->b_bus_suspend = 1;
 679                         /*
 680                          * Init a timer to know how long this suspend
 681                          * will continue, if time out, indicates B no longer
 682                          * wants to be host role
 683                          */
 684                          ci_otg_add_timer(ci, A_BIDL_ADIS);
 685                 }
 686
 687                 if (intr_sts & USBi_URI)
 688                         ci_otg_del_timer(ci, A_BIDL_ADIS);
 689
 690                 if (intr_sts & USBi_PCI) {
 691                         if (fsm->b_bus_suspend == 1) {
 692                                 ci_otg_del_timer(ci, A_BIDL_ADIS);
 693                                 fsm->b_bus_suspend = 0;
 694                         }
 695                 }
 696                 break;
 697         case OTG_STATE_A_SUSPEND:
 698                 if ((intr_sts & USBi_PCI) && !port_conn) {
 699                         fsm->b_conn = 0;
 700
 701                         /* if gadget driver is binded */
 702                         if (ci->driver) {
 703                                 /* A device to be peripheral mode */
 704                                 ci->gadget.is_a_peripheral = 1;
 705                         }
 706                         ci_otg_queue_work(ci);
 707                 }
 708                 break;
 709         case OTG_STATE_A_HOST:
 710                 if ((intr_sts & USBi_PCI) && !port_conn) {
 711                         fsm->b_conn = 0;
 712                         ci_otg_queue_work(ci);
 713                 }
 714                 break;
 715         case OTG_STATE_B_WAIT_ACON:
 716                 if ((intr_sts & USBi_PCI) && port_conn) {
 717                         fsm->a_conn = 1;
 718                         ci_otg_queue_work(ci);
 719                 }
 720                 break;
 721         default:
 722                 break;
 723         }
 724 }
 725
 726 /*
 727  * ci_otg_irq - otg fsm related irq handling
 728  * and also update otg fsm variable by monitoring usb host and udc
 729  * state change interrupts.
 730  * @ci: ci_hdrc
 731  */
 732 irqreturn_t ci_otg_fsm_irq(struct ci_hdrc *ci)
 733 {
 734         irqreturn_t retval =  IRQ_NONE;
 735         u32 otgsc, otg_int_src = 0;
 736         struct otg_fsm *fsm = &ci->fsm;
 737
 738         otgsc = hw_read_otgsc(ci, ~0);
 739         otg_int_src = otgsc & OTGSC_INT_STATUS_BITS & (otgsc >> 8);
 740         fsm->id = (otgsc & OTGSC_ID) ? 1 : 0;
 741
 742         if (otg_int_src) {
 743                 if (otg_int_src & OTGSC_DPIS) {
 744                         hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
 745                         fsm->a_srp_det = 1;
 746                         fsm->a_bus_drop = 0;
 747                 } else if (otg_int_src & OTGSC_IDIS) {
 748                         hw_write_otgsc(ci, OTGSC_IDIS, OTGSC_IDIS);
 749                         if (fsm->id == 0) {
 750                                 fsm->a_bus_drop = 0;
 751                                 fsm->a_bus_req = 1;
 752                                 ci->id_event = true;
 753                         }
 754                 } else if (otg_int_src & OTGSC_BSVIS) {
 755                         hw_write_otgsc(ci, OTGSC_BSVIS, OTGSC_BSVIS);
 756                         if (otgsc & OTGSC_BSV) {
 757                                 fsm->b_sess_vld = 1;
 758                                 ci_otg_del_timer(ci, B_SSEND_SRP);
 759                                 ci_otg_del_timer(ci, B_SRP_FAIL);
 760                                 fsm->b_ssend_srp = 0;
 761                         } else {
 762                                 fsm->b_sess_vld = 0;
 763                                 if (fsm->id)
 764                                         ci_otg_add_timer(ci, B_SSEND_SRP);
 765                         }
 766                 } else if (otg_int_src & OTGSC_AVVIS) {
 767                         hw_write_otgsc(ci, OTGSC_AVVIS, OTGSC_AVVIS);
 768                         if (otgsc & OTGSC_AVV) {
 769                                 fsm->a_vbus_vld = 1;
 770                         } else {
 771                                 fsm->a_vbus_vld = 0;
 772                                 fsm->b_conn = 0;
 773                         }
 774                 }
 775                 ci_otg_queue_work(ci);
 776                 return IRQ_HANDLED;
 777         }
 778
 779         ci_otg_fsm_event(ci);
 780
 781         return retval;
 782 }
 783
 784 void ci_hdrc_otg_fsm_start(struct ci_hdrc *ci)
 785 {
 786         ci_otg_queue_work(ci);
 787 }
 788
 789 int ci_hdrc_otg_fsm_init(struct ci_hdrc *ci)
 790 {
 791         int retval = 0;
 792
 793         if (ci->phy)
 794                 ci->otg.phy = ci->phy;
 795         else
 796                 ci->otg.usb_phy = ci->usb_phy;
 797
 798         ci->otg.gadget = &ci->gadget;
 799         ci->fsm.otg = &ci->otg;
 800         ci->fsm.power_up = 1;
 801         ci->fsm.id = hw_read_otgsc(ci, OTGSC_ID) ? 1 : 0;
 802         ci->fsm.otg->state = OTG_STATE_UNDEFINED;
 803         ci->fsm.ops = &ci_otg_ops;
 804         ci->gadget.hnp_polling_support = 1;
 805         ci->fsm.host_req_flag = devm_kzalloc(ci->dev, 1, GFP_KERNEL);
 806         if (!ci->fsm.host_req_flag)
 807                 return -ENOMEM;
 808
 809         mutex_init(&ci->fsm.lock);
 810
 811         retval = ci_otg_init_timers(ci);
 812         if (retval) {
 813                 dev_err(ci->dev, "Couldn't init OTG timers\n");
 814                 return retval;
 815         }
 816         ci->enabled_otg_timer_bits = 0;
 817         ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
 818
 819         retval = sysfs_create_group(&ci->dev->kobj, &inputs_attr_group);
 820         if (retval < 0) {
 821                 dev_dbg(ci->dev,
 822                         "Can't register sysfs attr group: %d\n", retval);
 823                 return retval;
 824         }
 825
 826         /* Enable A vbus valid irq */
 827         hw_write_otgsc(ci, OTGSC_AVVIE, OTGSC_AVVIE);
 828
 829         if (ci->fsm.id) {
 830                 ci->fsm.b_ssend_srp =
 831                         hw_read_otgsc(ci, OTGSC_BSV) ? 0 : 1;
 832                 ci->fsm.b_sess_vld =
 833                         hw_read_otgsc(ci, OTGSC_BSV) ? 1 : 0;
 834                 /* Enable BSV irq */
 835                 hw_write_otgsc(ci, OTGSC_BSVIE, OTGSC_BSVIE);
 836         }
 837
 838         return 0;
 839 }
 840
 841 void ci_hdrc_otg_fsm_remove(struct ci_hdrc *ci)
 842 {
 843         sysfs_remove_group(&ci->dev->kobj, &inputs_attr_group);
 844 }