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                         spin_unlock_irqrestore(&ci->lock, flags);
 260                         /* No enabled timers after delete it */
 261                         hrtimer_cancel(&ci->otg_fsm_hrtimer);
 262                         spin_lock_irqsave(&ci->lock, flags);
 263                         ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
 264                 } else {
 265                         /* Find the next timer */
 266                         enabled_timer_bits = ci->enabled_otg_timer_bits;
 267                         for_each_set_bit(cur_timer, &enabled_timer_bits,
 268                                                         NUM_OTG_FSM_TIMERS) {
 269                                 if ((next_timer == NUM_OTG_FSM_TIMERS) ||
 270                                         ktime_before(ci->hr_timeouts[next_timer],
 271                                          ci->hr_timeouts[cur_timer]))
 272                                         next_timer = cur_timer;
 273                         }
 274                 }
 275         }
 276         if (next_timer != NUM_OTG_FSM_TIMERS) {
 277                 ci->next_otg_timer = next_timer;
 278                 hrtimer_start_range_ns(&ci->otg_fsm_hrtimer,
 279                         ci->hr_timeouts[next_timer], NSEC_PER_MSEC,
 280                                                         HRTIMER_MODE_ABS);
 281         }
 282         spin_unlock_irqrestore(&ci->lock, flags);
 283 }
 284
 285 /* OTG FSM timer handlers */
 286 static int a_wait_vrise_tmout(struct ci_hdrc *ci)
 287 {
 288         ci->fsm.a_wait_vrise_tmout = 1;
 289         return 0;
 290 }
 291
 292 static int a_wait_vfall_tmout(struct ci_hdrc *ci)
 293 {
 294         ci->fsm.a_wait_vfall_tmout = 1;
 295         return 0;
 296 }
 297
 298 static int a_wait_bcon_tmout(struct ci_hdrc *ci)
 299 {
 300         ci->fsm.a_wait_bcon_tmout = 1;
 301         return 0;
 302 }
 303
 304 static int a_aidl_bdis_tmout(struct ci_hdrc *ci)
 305 {
 306         ci->fsm.a_aidl_bdis_tmout = 1;
 307         return 0;
 308 }
 309
 310 static int b_ase0_brst_tmout(struct ci_hdrc *ci)
 311 {
 312         ci->fsm.b_ase0_brst_tmout = 1;
 313         return 0;
 314 }
 315
 316 static int a_bidl_adis_tmout(struct ci_hdrc *ci)
 317 {
 318         ci->fsm.a_bidl_adis_tmout = 1;
 319         return 0;
 320 }
 321
 322 static int b_aidl_bdis_tmout(struct ci_hdrc *ci)
 323 {
 324         ci->fsm.a_bus_suspend = 1;
 325         return 0;
 326 }
 327
 328 static int b_se0_srp_tmout(struct ci_hdrc *ci)
 329 {
 330         ci->fsm.b_se0_srp = 1;
 331         return 0;
 332 }
 333
 334 static int b_srp_fail_tmout(struct ci_hdrc *ci)
 335 {
 336         ci->fsm.b_srp_done = 1;
 337         return 1;
 338 }
 339
 340 static int b_data_pls_tmout(struct ci_hdrc *ci)
 341 {
 342         ci->fsm.b_srp_done = 1;
 343         ci->fsm.b_bus_req = 0;
 344         if (ci->fsm.power_up)
 345                 ci->fsm.power_up = 0;
 346         hw_write_otgsc(ci, OTGSC_HABA, 0);
 347         pm_runtime_put(ci->dev);
 348         return 0;
 349 }
 350
 351 static int b_ssend_srp_tmout(struct ci_hdrc *ci)
 352 {
 353         ci->fsm.b_ssend_srp = 1;
 354         /* only vbus fall below B_sess_vld in b_idle state */
 355         if (ci->fsm.otg->state == OTG_STATE_B_IDLE)
 356                 return 0;
 357         else
 358                 return 1;
 359 }
 360
 361 /*
 362  * Keep this list in the same order as timers indexed
 363  * by enum otg_fsm_timer in include/linux/usb/otg-fsm.h
 364  */
 365 static int (*otg_timer_handlers[])(struct ci_hdrc *) = {
 366         a_wait_vrise_tmout,     /* A_WAIT_VRISE */
 367         a_wait_vfall_tmout,     /* A_WAIT_VFALL */
 368         a_wait_bcon_tmout,      /* A_WAIT_BCON */
 369         a_aidl_bdis_tmout,      /* A_AIDL_BDIS */
 370         b_ase0_brst_tmout,      /* B_ASE0_BRST */
 371         a_bidl_adis_tmout,      /* A_BIDL_ADIS */
 372         b_aidl_bdis_tmout,      /* B_AIDL_BDIS */
 373         b_se0_srp_tmout,        /* B_SE0_SRP */
 374         b_srp_fail_tmout,       /* B_SRP_FAIL */
 375         NULL,                   /* A_WAIT_ENUM */
 376         b_data_pls_tmout,       /* B_DATA_PLS */
 377         b_ssend_srp_tmout,      /* B_SSEND_SRP */
 378 };
 379
 380 /*
 381  * Enable the next nearest enabled timer if have
 382  */
 383 static enum hrtimer_restart ci_otg_hrtimer_func(struct hrtimer *t)
 384 {
 385         struct ci_hdrc *ci = container_of(t, struct ci_hdrc, otg_fsm_hrtimer);
 386         ktime_t now, *timeout;
 387         unsigned long   enabled_timer_bits;
 388         unsigned long   flags;
 389         enum otg_fsm_timer cur_timer, next_timer = NUM_OTG_FSM_TIMERS;
 390         int ret = -EINVAL;
 391
 392         spin_lock_irqsave(&ci->lock, flags);
 393         enabled_timer_bits = ci->enabled_otg_timer_bits;
 394         ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
 395
 396         now = ktime_get();
 397         for_each_set_bit(cur_timer, &enabled_timer_bits, NUM_OTG_FSM_TIMERS) {
 398                 if (ktime_compare(now, ci->hr_timeouts[cur_timer]) >= 0) {
 399                         ci->enabled_otg_timer_bits &= ~(1 << cur_timer);
 400                         if (otg_timer_handlers[cur_timer])
 401                                 ret = otg_timer_handlers[cur_timer](ci);
 402                 } else {
 403                         if ((next_timer == NUM_OTG_FSM_TIMERS) ||
 404                                 ktime_before(ci->hr_timeouts[cur_timer],
 405                                         ci->hr_timeouts[next_timer]))
 406                                 next_timer = cur_timer;
 407                 }
 408         }
 409         /* Enable the next nearest timer */
 410         if (next_timer < NUM_OTG_FSM_TIMERS) {
 411                 timeout = &ci->hr_timeouts[next_timer];
 412                 hrtimer_start_range_ns(&ci->otg_fsm_hrtimer, *timeout,
 413                                         NSEC_PER_MSEC, HRTIMER_MODE_ABS);
 414                 ci->next_otg_timer = next_timer;
 415         }
 416         spin_unlock_irqrestore(&ci->lock, flags);
 417
 418         if (!ret)
 419                 ci_otg_queue_work(ci);
 420
 421         return HRTIMER_NORESTART;
 422 }
 423
 424 /* Initialize timers */
 425 static int ci_otg_init_timers(struct ci_hdrc *ci)
 426 {
 427         hrtimer_init(&ci->otg_fsm_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 428         ci->otg_fsm_hrtimer.function = ci_otg_hrtimer_func;
 429
 430         return 0;
 431 }
 432
 433 /* -------------------------------------------------------------*/
 434 /* Operations that will be called from OTG Finite State Machine */
 435 /* -------------------------------------------------------------*/
 436 static void ci_otg_fsm_add_timer(struct otg_fsm *fsm, enum otg_fsm_timer t)
 437 {
 438         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 439
 440         if (t < NUM_OTG_FSM_TIMERS)
 441                 ci_otg_add_timer(ci, t);
 442         return;
 443 }
 444
 445 static void ci_otg_fsm_del_timer(struct otg_fsm *fsm, enum otg_fsm_timer t)
 446 {
 447         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 448
 449         if (t < NUM_OTG_FSM_TIMERS)
 450                 ci_otg_del_timer(ci, t);
 451         return;
 452 }
 453
 454 /*
 455  * A-device drive vbus: turn on vbus regulator and enable port power
 456  * Data pulse irq should be disabled while vbus is on.
 457  */
 458 static void ci_otg_drv_vbus(struct otg_fsm *fsm, int on)
 459 {
 460         int ret;
 461         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 462
 463         if (on) {
 464                 /* Enable power */
 465                 hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS | PORTSC_PP,
 466                                                         PORTSC_PP);
 467                 if (ci->platdata->reg_vbus) {
 468                         ret = regulator_enable(ci->platdata->reg_vbus);
 469                         if (ret) {
 470                                 dev_err(ci->dev,
 471                                 "Failed to enable vbus regulator, ret=%d\n",
 472                                 ret);
 473                                 return;
 474                         }
 475                 }
 476
 477                 if (ci->platdata->flags & CI_HDRC_PHY_VBUS_CONTROL)
 478                         usb_phy_vbus_on(ci->usb_phy);
 479
 480                 /* Disable data pulse irq */
 481                 hw_write_otgsc(ci, OTGSC_DPIE, 0);
 482
 483                 fsm->a_srp_det = 0;
 484                 fsm->power_up = 0;
 485         } else {
 486                 if (ci->platdata->reg_vbus)
 487                         regulator_disable(ci->platdata->reg_vbus);
 488
 489                 if (ci->platdata->flags & CI_HDRC_PHY_VBUS_CONTROL)
 490                         usb_phy_vbus_off(ci->usb_phy);
 491
 492                 fsm->a_bus_drop = 1;
 493                 fsm->a_bus_req = 0;
 494         }
 495 }
 496
 497 /*
 498  * Control data line by Run Stop bit.
 499  */
 500 static void ci_otg_loc_conn(struct otg_fsm *fsm, int on)
 501 {
 502         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 503
 504         if (on)
 505                 hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
 506         else
 507                 hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
 508 }
 509
 510 /*
 511  * Generate SOF by host.
 512  * In host mode, controller will automatically send SOF.
 513  * Suspend will block the data on the port.
 514  *
 515  * This is controlled through usbcore by usb autosuspend,
 516  * so the usb device class driver need support autosuspend,
 517  * otherwise the bus suspend will not happen.
 518  */
 519 static void ci_otg_loc_sof(struct otg_fsm *fsm, int on)
 520 {
 521         struct usb_device *udev;
 522
 523         if (!fsm->otg->host)
 524                 return;
 525
 526         udev = usb_hub_find_child(fsm->otg->host->root_hub, 1);
 527         if (!udev)
 528                 return;
 529
 530         if (on) {
 531                 usb_disable_autosuspend(udev);
 532         } else {
 533                 pm_runtime_set_autosuspend_delay(&udev->dev, 0);
 534                 usb_enable_autosuspend(udev);
 535         }
 536 }
 537
 538 /*
 539  * Start SRP pulsing by data-line pulsing,
 540  * no v-bus pulsing followed
 541  */
 542 static void ci_otg_start_pulse(struct otg_fsm *fsm)
 543 {
 544         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 545
 546         /* Hardware Assistant Data pulse */
 547         hw_write_otgsc(ci, OTGSC_HADP, OTGSC_HADP);
 548
 549         pm_runtime_get(ci->dev);
 550         ci_otg_add_timer(ci, B_DATA_PLS);
 551 }
 552
 553 static int ci_otg_start_host(struct otg_fsm *fsm, int on)
 554 {
 555         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 556
 557         if (on) {
 558                 ci_role_stop(ci);
 559                 ci_role_start(ci, CI_ROLE_HOST);
 560         } else {
 561                 ci_role_stop(ci);
 562                 ci_role_start(ci, CI_ROLE_GADGET);
 563         }
 564         return 0;
 565 }
 566
 567 static int ci_otg_start_gadget(struct otg_fsm *fsm, int on)
 568 {
 569         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 570
 571         if (on)
 572                 usb_gadget_vbus_connect(&ci->gadget);
 573         else
 574                 usb_gadget_vbus_disconnect(&ci->gadget);
 575
 576         return 0;
 577 }
 578
 579 static struct otg_fsm_ops ci_otg_ops = {
 580         .drv_vbus = ci_otg_drv_vbus,
 581         .loc_conn = ci_otg_loc_conn,
 582         .loc_sof = ci_otg_loc_sof,
 583         .start_pulse = ci_otg_start_pulse,
 584         .add_timer = ci_otg_fsm_add_timer,
 585         .del_timer = ci_otg_fsm_del_timer,
 586         .start_host = ci_otg_start_host,
 587         .start_gadget = ci_otg_start_gadget,
 588 };
 589
 590 int ci_otg_fsm_work(struct ci_hdrc *ci)
 591 {
 592         /*
 593          * Don't do fsm transition for B device
 594          * when there is no gadget class driver
 595          */
 596         if (ci->fsm.id && !(ci->driver) &&
 597                 ci->fsm.otg->state < OTG_STATE_A_IDLE)
 598                 return 0;
 599
 600         pm_runtime_get_sync(ci->dev);
 601         if (otg_statemachine(&ci->fsm)) {
 602                 if (ci->fsm.otg->state == OTG_STATE_A_IDLE) {
 603                         /*
 604                          * Further state change for cases:
 605                          * a_idle to b_idle; or
 606                          * a_idle to a_wait_vrise due to ID change(1->0), so
 607                          * B-dev becomes A-dev can try to start new session
 608                          * consequently; or
 609                          * a_idle to a_wait_vrise when power up
 610                          */
 611                         if ((ci->fsm.id) || (ci->id_event) ||
 612                                                 (ci->fsm.power_up)) {
 613                                 ci_otg_queue_work(ci);
 614                         } else {
 615                                 /* Enable data pulse irq */
 616                                 hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS |
 617                                                                 PORTSC_PP, 0);
 618                                 hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
 619                                 hw_write_otgsc(ci, OTGSC_DPIE, OTGSC_DPIE);
 620                         }
 621                         if (ci->id_event)
 622                                 ci->id_event = false;
 623                 } else if (ci->fsm.otg->state == OTG_STATE_B_IDLE) {
 624                         if (ci->fsm.b_sess_vld) {
 625                                 ci->fsm.power_up = 0;
 626                                 /*
 627                                  * Further transite to b_periphearl state
 628                                  * when register gadget driver with vbus on
 629                                  */
 630                                 ci_otg_queue_work(ci);
 631                         }
 632                 } else if (ci->fsm.otg->state == OTG_STATE_A_HOST) {
 633                         pm_runtime_mark_last_busy(ci->dev);
 634                         pm_runtime_put_autosuspend(ci->dev);
 635                         return 0;
 636                 }
 637         }
 638         pm_runtime_put_sync(ci->dev);
 639         return 0;
 640 }
 641
 642 /*
 643  * Update fsm variables in each state if catching expected interrupts,
 644  * called by otg fsm isr.
 645  */
 646 static void ci_otg_fsm_event(struct ci_hdrc *ci)
 647 {
 648         u32 intr_sts, otg_bsess_vld, port_conn;
 649         struct otg_fsm *fsm = &ci->fsm;
 650
 651         intr_sts = hw_read_intr_status(ci);
 652         otg_bsess_vld = hw_read_otgsc(ci, OTGSC_BSV);
 653         port_conn = hw_read(ci, OP_PORTSC, PORTSC_CCS);
 654
 655         switch (ci->fsm.otg->state) {
 656         case OTG_STATE_A_WAIT_BCON:
 657                 if (port_conn) {
 658                         fsm->b_conn = 1;
 659                         fsm->a_bus_req = 1;
 660                         ci_otg_queue_work(ci);
 661                 }
 662                 break;
 663         case OTG_STATE_B_IDLE:
 664                 if (otg_bsess_vld && (intr_sts & USBi_PCI) && port_conn) {
 665                         fsm->b_sess_vld = 1;
 666                         ci_otg_queue_work(ci);
 667                 }
 668                 break;
 669         case OTG_STATE_B_PERIPHERAL:
 670                 if ((intr_sts & USBi_SLI) && port_conn && otg_bsess_vld) {
 671                         ci_otg_add_timer(ci, B_AIDL_BDIS);
 672                 } else if (intr_sts & USBi_PCI) {
 673                         ci_otg_del_timer(ci, B_AIDL_BDIS);
 674                         if (fsm->a_bus_suspend == 1)
 675                                 fsm->a_bus_suspend = 0;
 676                 }
 677                 break;
 678         case OTG_STATE_B_HOST:
 679                 if ((intr_sts & USBi_PCI) && !port_conn) {
 680                         fsm->a_conn = 0;
 681                         fsm->b_bus_req = 0;
 682                         ci_otg_queue_work(ci);
 683                 }
 684                 break;
 685         case OTG_STATE_A_PERIPHERAL:
 686                 if (intr_sts & USBi_SLI) {
 687                          fsm->b_bus_suspend = 1;
 688                         /*
 689                          * Init a timer to know how long this suspend
 690                          * will continue, if time out, indicates B no longer
 691                          * wants to be host role
 692                          */
 693                          ci_otg_add_timer(ci, A_BIDL_ADIS);
 694                 }
 695
 696                 if (intr_sts & USBi_URI)
 697                         ci_otg_del_timer(ci, A_BIDL_ADIS);
 698
 699                 if (intr_sts & USBi_PCI) {
 700                         if (fsm->b_bus_suspend == 1) {
 701                                 ci_otg_del_timer(ci, A_BIDL_ADIS);
 702                                 fsm->b_bus_suspend = 0;
 703                         }
 704                 }
 705                 break;
 706         case OTG_STATE_A_SUSPEND:
 707                 if ((intr_sts & USBi_PCI) && !port_conn) {
 708                         fsm->b_conn = 0;
 709
 710                         /* if gadget driver is binded */
 711                         if (ci->driver) {
 712                                 /* A device to be peripheral mode */
 713                                 ci->gadget.is_a_peripheral = 1;
 714                         }
 715                         ci_otg_queue_work(ci);
 716                 }
 717                 break;
 718         case OTG_STATE_A_HOST:
 719                 if ((intr_sts & USBi_PCI) && !port_conn) {
 720                         fsm->b_conn = 0;
 721                         ci_otg_queue_work(ci);
 722                 }
 723                 break;
 724         case OTG_STATE_B_WAIT_ACON:
 725                 if ((intr_sts & USBi_PCI) && port_conn) {
 726                         fsm->a_conn = 1;
 727                         ci_otg_queue_work(ci);
 728                 }
 729                 break;
 730         default:
 731                 break;
 732         }
 733 }
 734
 735 /*
 736  * ci_otg_irq - otg fsm related irq handling
 737  * and also update otg fsm variable by monitoring usb host and udc
 738  * state change interrupts.
 739  * @ci: ci_hdrc
 740  */
 741 irqreturn_t ci_otg_fsm_irq(struct ci_hdrc *ci)
 742 {
 743         irqreturn_t retval =  IRQ_NONE;
 744         u32 otgsc, otg_int_src = 0;
 745         struct otg_fsm *fsm = &ci->fsm;
 746
 747         otgsc = hw_read_otgsc(ci, ~0);
 748         otg_int_src = otgsc & OTGSC_INT_STATUS_BITS & (otgsc >> 8);
 749         fsm->id = (otgsc & OTGSC_ID) ? 1 : 0;
 750
 751         if (otg_int_src) {
 752                 if (otg_int_src & OTGSC_DPIS) {
 753                         hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
 754                         fsm->a_srp_det = 1;
 755                         fsm->a_bus_drop = 0;
 756                 } else if (otg_int_src & OTGSC_IDIS) {
 757                         hw_write_otgsc(ci, OTGSC_IDIS, OTGSC_IDIS);
 758                         if (fsm->id == 0) {
 759                                 fsm->a_bus_drop = 0;
 760                                 fsm->a_bus_req = 1;
 761                                 ci->id_event = true;
 762                         }
 763                 } else if (otg_int_src & OTGSC_BSVIS) {
 764                         hw_write_otgsc(ci, OTGSC_BSVIS, OTGSC_BSVIS);
 765                         if (otgsc & OTGSC_BSV) {
 766                                 fsm->b_sess_vld = 1;
 767                                 ci_otg_del_timer(ci, B_SSEND_SRP);
 768                                 ci_otg_del_timer(ci, B_SRP_FAIL);
 769                                 fsm->b_ssend_srp = 0;
 770                         } else {
 771                                 fsm->b_sess_vld = 0;
 772                                 if (fsm->id)
 773                                         ci_otg_add_timer(ci, B_SSEND_SRP);
 774                         }
 775                 } else if (otg_int_src & OTGSC_AVVIS) {
 776                         hw_write_otgsc(ci, OTGSC_AVVIS, OTGSC_AVVIS);
 777                         if (otgsc & OTGSC_AVV) {
 778                                 fsm->a_vbus_vld = 1;
 779                         } else {
 780                                 fsm->a_vbus_vld = 0;
 781                                 fsm->b_conn = 0;
 782                         }
 783                 }
 784                 ci_otg_queue_work(ci);
 785                 return IRQ_HANDLED;
 786         }
 787
 788         ci_otg_fsm_event(ci);
 789
 790         return retval;
 791 }
 792
 793 void ci_hdrc_otg_fsm_start(struct ci_hdrc *ci)
 794 {
 795         ci_otg_queue_work(ci);
 796 }
 797
 798 int ci_hdrc_otg_fsm_init(struct ci_hdrc *ci)
 799 {
 800         int retval = 0;
 801
 802         if (ci->phy)
 803                 ci->otg.phy = ci->phy;
 804         else
 805                 ci->otg.usb_phy = ci->usb_phy;
 806
 807         ci->otg.gadget = &ci->gadget;
 808         ci->fsm.otg = &ci->otg;
 809         ci->fsm.power_up = 1;
 810         ci->fsm.id = hw_read_otgsc(ci, OTGSC_ID) ? 1 : 0;
 811         ci->fsm.otg->state = OTG_STATE_UNDEFINED;
 812         ci->fsm.ops = &ci_otg_ops;
 813         ci->gadget.hnp_polling_support = 1;
 814         ci->fsm.host_req_flag = devm_kzalloc(ci->dev, 1, GFP_KERNEL);
 815         if (!ci->fsm.host_req_flag)
 816                 return -ENOMEM;
 817
 818         mutex_init(&ci->fsm.lock);
 819
 820         retval = ci_otg_init_timers(ci);
 821         if (retval) {
 822                 dev_err(ci->dev, "Couldn't init OTG timers\n");
 823                 return retval;
 824         }
 825         ci->enabled_otg_timer_bits = 0;
 826         ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
 827
 828         retval = sysfs_create_group(&ci->dev->kobj, &inputs_attr_group);
 829         if (retval < 0) {
 830                 dev_dbg(ci->dev,
 831                         "Can't register sysfs attr group: %d\n", retval);
 832                 return retval;
 833         }
 834
 835         /* Enable A vbus valid irq */
 836         hw_write_otgsc(ci, OTGSC_AVVIE, OTGSC_AVVIE);
 837
 838         if (ci->fsm.id) {
 839                 ci->fsm.b_ssend_srp =
 840                         hw_read_otgsc(ci, OTGSC_BSV) ? 0 : 1;
 841                 ci->fsm.b_sess_vld =
 842                         hw_read_otgsc(ci, OTGSC_BSV) ? 1 : 0;
 843                 /* Enable BSV irq */
 844                 hw_write_otgsc(ci, OTGSC_BSVIE, OTGSC_BSVIE);
 845         }
 846
 847         return 0;
 848 }
 849
 850 void ci_hdrc_otg_fsm_remove(struct ci_hdrc *ci)
 851 {
 852         sysfs_remove_group(&ci->dev->kobj, &inputs_attr_group);
 853 }