drivers/usb/chipidea/otg_fsm.c

   1 /*
   2  * otg_fsm.c - ChipIdea USB IP core OTG FSM driver
   3  *
   4  * Copyright (C) 2014 Freescale Semiconductor, Inc.
   5  *
   6  * Author: Jun Li
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 /*
  14  * This file mainly handles OTG fsm, it includes OTG fsm operations
  15  * for HNP and SRP.
  16  *
  17  * TODO List
  18  * - ADP
  19  * - OTG test device
  20  */
  21
  22 #include <linux/usb/otg.h>
  23 #include <linux/usb/gadget.h>
  24 #include <linux/usb/hcd.h>
  25 #include <linux/usb/chipidea.h>
  26 #include <linux/regulator/consumer.h>
  27
  28 #include "ci.h"
  29 #include "bits.h"
  30 #include "otg.h"
  31 #include "otg_fsm.h"
  32
  33 /* Add for otg: interact with user space app */
  34 static ssize_t
  35 get_a_bus_req(struct device *dev, struct device_attribute *attr, char *buf)
  36 {
  37         char            *next;
  38         unsigned        size, t;
  39         struct ci_hdrc  *ci = dev_get_drvdata(dev);
  40
  41         next = buf;
  42         size = PAGE_SIZE;
  43         t = scnprintf(next, size, "%d\n", ci->fsm.a_bus_req);
  44         size -= t;
  45         next += t;
  46
  47         return PAGE_SIZE - size;
  48 }
  49
  50 static ssize_t
  51 set_a_bus_req(struct device *dev, struct device_attribute *attr,
  52                                         const char *buf, size_t count)
  53 {
  54         struct ci_hdrc *ci = dev_get_drvdata(dev);
  55
  56         if (count > 2)
  57                 return -1;
  58
  59         mutex_lock(&ci->fsm.lock);
  60         if (buf[0] == '0') {
  61                 ci->fsm.a_bus_req = 0;
  62         } else if (buf[0] == '1') {
  63                 /* If a_bus_drop is TRUE, a_bus_req can't be set */
  64                 if (ci->fsm.a_bus_drop) {
  65                         mutex_unlock(&ci->fsm.lock);
  66                         return count;
  67                 }
  68                 ci->fsm.a_bus_req = 1;
  69                 if (ci->fsm.otg->state == OTG_STATE_A_PERIPHERAL) {
  70                         ci->gadget.host_request_flag = 1;
  71                         mutex_unlock(&ci->fsm.lock);
  72                         return count;
  73                 }
  74         }
  75
  76         ci_otg_queue_work(ci);
  77         mutex_unlock(&ci->fsm.lock);
  78
  79         return count;
  80 }
  81 static DEVICE_ATTR(a_bus_req, S_IRUGO | S_IWUSR, get_a_bus_req, set_a_bus_req);
  82
  83 static ssize_t
  84 get_a_bus_drop(struct device *dev, struct device_attribute *attr, char *buf)
  85 {
  86         char            *next;
  87         unsigned        size, t;
  88         struct ci_hdrc  *ci = dev_get_drvdata(dev);
  89
  90         next = buf;
  91         size = PAGE_SIZE;
  92         t = scnprintf(next, size, "%d\n", ci->fsm.a_bus_drop);
  93         size -= t;
  94         next += t;
  95
  96         return PAGE_SIZE - size;
  97 }
  98
  99 static ssize_t
 100 set_a_bus_drop(struct device *dev, struct device_attribute *attr,
 101                                         const char *buf, size_t count)
 102 {
 103         struct ci_hdrc  *ci = dev_get_drvdata(dev);
 104
 105         if (count > 2)
 106                 return -1;
 107
 108         mutex_lock(&ci->fsm.lock);
 109         if (buf[0] == '0') {
 110                 ci->fsm.a_bus_drop = 0;
 111         } else if (buf[0] == '1') {
 112                 ci->fsm.a_bus_drop = 1;
 113                 ci->fsm.a_bus_req = 0;
 114         }
 115
 116         ci_otg_queue_work(ci);
 117         mutex_unlock(&ci->fsm.lock);
 118
 119         return count;
 120 }
 121 static DEVICE_ATTR(a_bus_drop, S_IRUGO | S_IWUSR, get_a_bus_drop,
 122                                                 set_a_bus_drop);
 123
 124 static ssize_t
 125 get_b_bus_req(struct device *dev, struct device_attribute *attr, char *buf)
 126 {
 127         char            *next;
 128         unsigned        size, t;
 129         struct ci_hdrc  *ci = dev_get_drvdata(dev);
 130
 131         next = buf;
 132         size = PAGE_SIZE;
 133         t = scnprintf(next, size, "%d\n", ci->fsm.b_bus_req);
 134         size -= t;
 135         next += t;
 136
 137         return PAGE_SIZE - size;
 138 }
 139
 140 static ssize_t
 141 set_b_bus_req(struct device *dev, struct device_attribute *attr,
 142                                         const char *buf, size_t count)
 143 {
 144         struct ci_hdrc  *ci = dev_get_drvdata(dev);
 145
 146         if (count > 2)
 147                 return -1;
 148
 149         mutex_lock(&ci->fsm.lock);
 150         if (buf[0] == '0')
 151                 ci->fsm.b_bus_req = 0;
 152         else if (buf[0] == '1') {
 153                 ci->fsm.b_bus_req = 1;
 154                 if (ci->fsm.otg->state == OTG_STATE_B_PERIPHERAL) {
 155                         ci->gadget.host_request_flag = 1;
 156                         mutex_unlock(&ci->fsm.lock);
 157                         return count;
 158                 }
 159         }
 160
 161         ci_otg_queue_work(ci);
 162         mutex_unlock(&ci->fsm.lock);
 163
 164         return count;
 165 }
 166 static DEVICE_ATTR(b_bus_req, S_IRUGO | S_IWUSR, get_b_bus_req, set_b_bus_req);
 167
 168 static ssize_t
 169 set_a_clr_err(struct device *dev, struct device_attribute *attr,
 170                                         const char *buf, size_t count)
 171 {
 172         struct ci_hdrc  *ci = dev_get_drvdata(dev);
 173
 174         if (count > 2)
 175                 return -1;
 176
 177         mutex_lock(&ci->fsm.lock);
 178         if (buf[0] == '1')
 179                 ci->fsm.a_clr_err = 1;
 180
 181         ci_otg_queue_work(ci);
 182         mutex_unlock(&ci->fsm.lock);
 183
 184         return count;
 185 }
 186 static DEVICE_ATTR(a_clr_err, S_IWUSR, NULL, set_a_clr_err);
 187
 188 static struct attribute *inputs_attrs[] = {
 189         &dev_attr_a_bus_req.attr,
 190         &dev_attr_a_bus_drop.attr,
 191         &dev_attr_b_bus_req.attr,
 192         &dev_attr_a_clr_err.attr,
 193         NULL,
 194 };
 195
 196 static struct attribute_group inputs_attr_group = {
 197         .name = "inputs",
 198         .attrs = inputs_attrs,
 199 };
 200
 201 /*
 202  * Keep this list in the same order as timers indexed
 203  * by enum otg_fsm_timer in include/linux/usb/otg-fsm.h
 204  */
 205 static unsigned otg_timer_ms[] = {
 206         TA_WAIT_VRISE,
 207         TA_WAIT_VFALL,
 208         TA_WAIT_BCON,
 209         TA_AIDL_BDIS,
 210         TB_ASE0_BRST,
 211         TA_BIDL_ADIS,
 212         TB_AIDL_BDIS,
 213         TB_SE0_SRP,
 214         TB_SRP_FAIL,
 215         0,
 216         TB_DATA_PLS,
 217         TB_SSEND_SRP,
 218 };
 219
 220 /*
 221  * Add timer to active timer list
 222  */
 223 static void ci_otg_add_timer(struct ci_hdrc *ci, enum otg_fsm_timer t)
 224 {
 225         unsigned long flags, timer_sec, timer_nsec;
 226
 227         if (t >= NUM_OTG_FSM_TIMERS)
 228                 return;
 229
 230         spin_lock_irqsave(&ci->lock, flags);
 231         timer_sec = otg_timer_ms[t] / MSEC_PER_SEC;
 232         timer_nsec = (otg_timer_ms[t] % MSEC_PER_SEC) * NSEC_PER_MSEC;
 233         ci->hr_timeouts[t] = ktime_add(ktime_get(),
 234                                 ktime_set(timer_sec, timer_nsec));
 235         ci->enabled_otg_timer_bits |= (1 << t);
 236         if ((ci->next_otg_timer == NUM_OTG_FSM_TIMERS) ||
 237                         (ci->hr_timeouts[ci->next_otg_timer].tv64 >
 238                                                 ci->hr_timeouts[t].tv64)) {
 239                         ci->next_otg_timer = t;
 240                         hrtimer_start_range_ns(&ci->otg_fsm_hrtimer,
 241                                         ci->hr_timeouts[t], NSEC_PER_MSEC,
 242                                                         HRTIMER_MODE_ABS);
 243         }
 244         spin_unlock_irqrestore(&ci->lock, flags);
 245 }
 246
 247 /*
 248  * Remove timer from active timer list
 249  */
 250 static void ci_otg_del_timer(struct ci_hdrc *ci, enum otg_fsm_timer t)
 251 {
 252         unsigned long flags, enabled_timer_bits;
 253         enum otg_fsm_timer cur_timer, next_timer = NUM_OTG_FSM_TIMERS;
 254
 255         if ((t >= NUM_OTG_FSM_TIMERS) ||
 256                         !(ci->enabled_otg_timer_bits & (1 << t)))
 257                 return;
 258
 259         spin_lock_irqsave(&ci->lock, flags);
 260         ci->enabled_otg_timer_bits &= ~(1 << t);
 261         if (ci->next_otg_timer == t) {
 262                 if (ci->enabled_otg_timer_bits == 0) {
 263                         /* No enabled timers after delete it */
 264                         hrtimer_cancel(&ci->otg_fsm_hrtimer);
 265                         ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
 266                 } else {
 267                         /* Find the next timer */
 268                         enabled_timer_bits = ci->enabled_otg_timer_bits;
 269                         for_each_set_bit(cur_timer, &enabled_timer_bits,
 270                                                         NUM_OTG_FSM_TIMERS) {
 271                                 if ((next_timer == NUM_OTG_FSM_TIMERS) ||
 272                                         (ci->hr_timeouts[next_timer].tv64 <
 273                                         ci->hr_timeouts[cur_timer].tv64))
 274                                         next_timer = cur_timer;
 275                         }
 276                 }
 277         }
 278         if (next_timer != NUM_OTG_FSM_TIMERS) {
 279                 ci->next_otg_timer = next_timer;
 280                 hrtimer_start_range_ns(&ci->otg_fsm_hrtimer,
 281                         ci->hr_timeouts[next_timer], NSEC_PER_MSEC,
 282                                                         HRTIMER_MODE_ABS);
 283         }
 284         spin_unlock_irqrestore(&ci->lock, flags);
 285 }
 286
 287 /* OTG FSM timer handlers */
 288 static int a_wait_vrise_tmout(struct ci_hdrc *ci)
 289 {
 290         ci->fsm.a_wait_vrise_tmout = 1;
 291         return 0;
 292 }
 293
 294 static int a_wait_vfall_tmout(struct ci_hdrc *ci)
 295 {
 296         ci->fsm.a_wait_vfall_tmout = 1;
 297         return 0;
 298 }
 299
 300 static int a_wait_bcon_tmout(struct ci_hdrc *ci)
 301 {
 302         ci->fsm.a_wait_bcon_tmout = 1;
 303         return 0;
 304 }
 305
 306 static int a_aidl_bdis_tmout(struct ci_hdrc *ci)
 307 {
 308         ci->fsm.a_aidl_bdis_tmout = 1;
 309         return 0;
 310 }
 311
 312 static int b_ase0_brst_tmout(struct ci_hdrc *ci)
 313 {
 314         ci->fsm.b_ase0_brst_tmout = 1;
 315         return 0;
 316 }
 317
 318 static int a_bidl_adis_tmout(struct ci_hdrc *ci)
 319 {
 320         ci->fsm.a_bidl_adis_tmout = 1;
 321         return 0;
 322 }
 323
 324 static int b_aidl_bdis_tmout(struct ci_hdrc *ci)
 325 {
 326         ci->fsm.a_bus_suspend = 1;
 327         return 0;
 328 }
 329
 330 static int b_se0_srp_tmout(struct ci_hdrc *ci)
 331 {
 332         ci->fsm.b_se0_srp = 1;
 333         return 0;
 334 }
 335
 336 static int b_srp_fail_tmout(struct ci_hdrc *ci)
 337 {
 338         ci->fsm.b_srp_done = 1;
 339         return 1;
 340 }
 341
 342 static int b_data_pls_tmout(struct ci_hdrc *ci)
 343 {
 344         ci->fsm.b_srp_done = 1;
 345         ci->fsm.b_bus_req = 0;
 346         if (ci->fsm.power_up)
 347                 ci->fsm.power_up = 0;
 348         hw_write_otgsc(ci, OTGSC_HABA, 0);
 349         pm_runtime_put(ci->dev);
 350         return 0;
 351 }
 352
 353 static int b_ssend_srp_tmout(struct ci_hdrc *ci)
 354 {
 355         ci->fsm.b_ssend_srp = 1;
 356         /* only vbus fall below B_sess_vld in b_idle state */
 357         if (ci->fsm.otg->state == OTG_STATE_B_IDLE)
 358                 return 0;
 359         else
 360                 return 1;
 361 }
 362
 363 /*
 364  * Keep this list in the same order as timers indexed
 365  * by enum otg_fsm_timer in include/linux/usb/otg-fsm.h
 366  */
 367 static int (*otg_timer_handlers[])(struct ci_hdrc *) = {
 368         a_wait_vrise_tmout,     /* A_WAIT_VRISE */
 369         a_wait_vfall_tmout,     /* A_WAIT_VFALL */
 370         a_wait_bcon_tmout,      /* A_WAIT_BCON */
 371         a_aidl_bdis_tmout,      /* A_AIDL_BDIS */
 372         b_ase0_brst_tmout,      /* B_ASE0_BRST */
 373         a_bidl_adis_tmout,      /* A_BIDL_ADIS */
 374         b_aidl_bdis_tmout,      /* B_AIDL_BDIS */
 375         b_se0_srp_tmout,        /* B_SE0_SRP */
 376         b_srp_fail_tmout,       /* B_SRP_FAIL */
 377         NULL,                   /* A_WAIT_ENUM */
 378         b_data_pls_tmout,       /* B_DATA_PLS */
 379         b_ssend_srp_tmout,      /* B_SSEND_SRP */
 380 };
 381
 382 /*
 383  * Enable the next nearest enabled timer if have
 384  */
 385 static enum hrtimer_restart ci_otg_hrtimer_func(struct hrtimer *t)
 386 {
 387         struct ci_hdrc *ci = container_of(t, struct ci_hdrc, otg_fsm_hrtimer);
 388         ktime_t now, *timeout;
 389         unsigned long   enabled_timer_bits;
 390         unsigned long   flags;
 391         enum otg_fsm_timer cur_timer, next_timer = NUM_OTG_FSM_TIMERS;
 392         int ret = -EINVAL;
 393
 394         spin_lock_irqsave(&ci->lock, flags);
 395         enabled_timer_bits = ci->enabled_otg_timer_bits;
 396         ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
 397
 398         now = ktime_get();
 399         for_each_set_bit(cur_timer, &enabled_timer_bits, NUM_OTG_FSM_TIMERS) {
 400                 if (now.tv64 >= ci->hr_timeouts[cur_timer].tv64) {
 401                         ci->enabled_otg_timer_bits &= ~(1 << cur_timer);
 402                         if (otg_timer_handlers[cur_timer])
 403                                 ret = otg_timer_handlers[cur_timer](ci);
 404                 } else {
 405                         if ((next_timer == NUM_OTG_FSM_TIMERS) ||
 406                                 (ci->hr_timeouts[cur_timer].tv64 <
 407                                         ci->hr_timeouts[next_timer].tv64))
 408                                 next_timer = cur_timer;
 409                 }
 410         }
 411         /* Enable the next nearest timer */
 412         if (next_timer < NUM_OTG_FSM_TIMERS) {
 413                 timeout = &ci->hr_timeouts[next_timer];
 414                 hrtimer_start_range_ns(&ci->otg_fsm_hrtimer, *timeout,
 415                                         NSEC_PER_MSEC, HRTIMER_MODE_ABS);
 416                 ci->next_otg_timer = next_timer;
 417         }
 418         spin_unlock_irqrestore(&ci->lock, flags);
 419
 420         if (!ret)
 421                 ci_otg_queue_work(ci);
 422
 423         return HRTIMER_NORESTART;
 424 }
 425
 426 /* Initialize timers */
 427 static int ci_otg_init_timers(struct ci_hdrc *ci)
 428 {
 429         hrtimer_init(&ci->otg_fsm_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 430         ci->otg_fsm_hrtimer.function = ci_otg_hrtimer_func;
 431
 432         return 0;
 433 }
 434
 435 /* -------------------------------------------------------------*/
 436 /* Operations that will be called from OTG Finite State Machine */
 437 /* -------------------------------------------------------------*/
 438 static void ci_otg_fsm_add_timer(struct otg_fsm *fsm, enum otg_fsm_timer t)
 439 {
 440         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 441
 442         if (t < NUM_OTG_FSM_TIMERS)
 443                 ci_otg_add_timer(ci, t);
 444         return;
 445 }
 446
 447 static void ci_otg_fsm_del_timer(struct otg_fsm *fsm, enum otg_fsm_timer t)
 448 {
 449         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 450
 451         if (t < NUM_OTG_FSM_TIMERS)
 452                 ci_otg_del_timer(ci, t);
 453         return;
 454 }
 455
 456 /*
 457  * A-device drive vbus: turn on vbus regulator and enable port power
 458  * Data pulse irq should be disabled while vbus is on.
 459  */
 460 static void ci_otg_drv_vbus(struct otg_fsm *fsm, int on)
 461 {
 462         int ret;
 463         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 464
 465         if (on) {
 466                 /* Enable power power */
 467                 hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS | PORTSC_PP,
 468                                                         PORTSC_PP);
 469                 if (ci->platdata->reg_vbus) {
 470                         ret = regulator_enable(ci->platdata->reg_vbus);
 471                         if (ret) {
 472                                 dev_err(ci->dev,
 473                                 "Failed to enable vbus regulator, ret=%d\n",
 474                                 ret);
 475                                 return;
 476                         }
 477                 }
 478                 /* Disable data pulse irq */
 479                 hw_write_otgsc(ci, OTGSC_DPIE, 0);
 480
 481                 fsm->a_srp_det = 0;
 482                 fsm->power_up = 0;
 483         } else {
 484                 if (ci->platdata->reg_vbus)
 485                         regulator_disable(ci->platdata->reg_vbus);
 486
 487                 fsm->a_bus_drop = 1;
 488                 fsm->a_bus_req = 0;
 489         }
 490 }
 491
 492 /*
 493  * Control data line by Run Stop bit.
 494  */
 495 static void ci_otg_loc_conn(struct otg_fsm *fsm, int on)
 496 {
 497         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 498
 499         if (on)
 500                 hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
 501         else
 502                 hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
 503 }
 504
 505 /*
 506  * Generate SOF by host.
 507  * In host mode, controller will automatically send SOF.
 508  * Suspend will block the data on the port.
 509  *
 510  * This is controlled through usbcore by usb autosuspend,
 511  * so the usb device class driver need support autosuspend,
 512  * otherwise the bus suspend will not happen.
 513  */
 514 static void ci_otg_loc_sof(struct otg_fsm *fsm, int on)
 515 {
 516         struct usb_device *udev;
 517
 518         if (!fsm->otg->host)
 519                 return;
 520
 521         udev = usb_hub_find_child(fsm->otg->host->root_hub, 1);
 522         if (!udev)
 523                 return;
 524
 525         if (on) {
 526                 usb_disable_autosuspend(udev);
 527         } else {
 528                 pm_runtime_set_autosuspend_delay(&udev->dev, 0);
 529                 usb_enable_autosuspend(udev);
 530         }
 531 }
 532
 533 /*
 534  * Start SRP pulsing by data-line pulsing,
 535  * no v-bus pulsing followed
 536  */
 537 static void ci_otg_start_pulse(struct otg_fsm *fsm)
 538 {
 539         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 540
 541         /* Hardware Assistant Data pulse */
 542         hw_write_otgsc(ci, OTGSC_HADP, OTGSC_HADP);
 543
 544         pm_runtime_get(ci->dev);
 545         ci_otg_add_timer(ci, B_DATA_PLS);
 546 }
 547
 548 static int ci_otg_start_host(struct otg_fsm *fsm, int on)
 549 {
 550         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 551
 552         if (on) {
 553                 ci_role_stop(ci);
 554                 ci_role_start(ci, CI_ROLE_HOST);
 555         } else {
 556                 ci_role_stop(ci);
 557                 ci_role_start(ci, CI_ROLE_GADGET);
 558         }
 559         return 0;
 560 }
 561
 562 static int ci_otg_start_gadget(struct otg_fsm *fsm, int on)
 563 {
 564         struct ci_hdrc  *ci = container_of(fsm, struct ci_hdrc, fsm);
 565
 566         if (on)
 567                 usb_gadget_vbus_connect(&ci->gadget);
 568         else
 569                 usb_gadget_vbus_disconnect(&ci->gadget);
 570
 571         return 0;
 572 }
 573
 574 static struct otg_fsm_ops ci_otg_ops = {
 575         .drv_vbus = ci_otg_drv_vbus,
 576         .loc_conn = ci_otg_loc_conn,
 577         .loc_sof = ci_otg_loc_sof,
 578         .start_pulse = ci_otg_start_pulse,
 579         .add_timer = ci_otg_fsm_add_timer,
 580         .del_timer = ci_otg_fsm_del_timer,
 581         .start_host = ci_otg_start_host,
 582         .start_gadget = ci_otg_start_gadget,
 583 };
 584
 585 int ci_otg_fsm_work(struct ci_hdrc *ci)
 586 {
 587         /*
 588          * Don't do fsm transition for B device
 589          * when there is no gadget class driver
 590          */
 591         if (ci->fsm.id && !(ci->driver) &&
 592                 ci->fsm.otg->state < OTG_STATE_A_IDLE)
 593                 return 0;
 594
 595         pm_runtime_get_sync(ci->dev);
 596         if (otg_statemachine(&ci->fsm)) {
 597                 if (ci->fsm.otg->state == OTG_STATE_A_IDLE) {
 598                         /*
 599                          * Further state change for cases:
 600                          * a_idle to b_idle; or
 601                          * a_idle to a_wait_vrise due to ID change(1->0), so
 602                          * B-dev becomes A-dev can try to start new session
 603                          * consequently; or
 604                          * a_idle to a_wait_vrise when power up
 605                          */
 606                         if ((ci->fsm.id) || (ci->id_event) ||
 607                                                 (ci->fsm.power_up)) {
 608                                 ci_otg_queue_work(ci);
 609                         } else {
 610                                 /* Enable data pulse irq */
 611                                 hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS |
 612                                                                 PORTSC_PP, 0);
 613                                 hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
 614                                 hw_write_otgsc(ci, OTGSC_DPIE, OTGSC_DPIE);
 615                         }
 616                         if (ci->id_event)
 617                                 ci->id_event = false;
 618                 } else if (ci->fsm.otg->state == OTG_STATE_B_IDLE) {
 619                         if (ci->fsm.b_sess_vld) {
 620                                 ci->fsm.power_up = 0;
 621                                 /*
 622                                  * Further transite to b_periphearl state
 623                                  * when register gadget driver with vbus on
 624                                  */
 625                                 ci_otg_queue_work(ci);
 626                         }
 627                 } else if (ci->fsm.otg->state == OTG_STATE_A_HOST) {
 628                         pm_runtime_mark_last_busy(ci->dev);
 629                         pm_runtime_put_autosuspend(ci->dev);
 630                         return 0;
 631                 }
 632         }
 633         pm_runtime_put_sync(ci->dev);
 634         return 0;
 635 }
 636
 637 /*
 638  * Update fsm variables in each state if catching expected interrupts,
 639  * called by otg fsm isr.
 640  */
 641 static void ci_otg_fsm_event(struct ci_hdrc *ci)
 642 {
 643         u32 intr_sts, otg_bsess_vld, port_conn;
 644         struct otg_fsm *fsm = &ci->fsm;
 645
 646         intr_sts = hw_read_intr_status(ci);
 647         otg_bsess_vld = hw_read_otgsc(ci, OTGSC_BSV);
 648         port_conn = hw_read(ci, OP_PORTSC, PORTSC_CCS);
 649
 650         switch (ci->fsm.otg->state) {
 651         case OTG_STATE_A_WAIT_BCON:
 652                 if (port_conn) {
 653                         fsm->b_conn = 1;
 654                         fsm->a_bus_req = 1;
 655                         ci_otg_queue_work(ci);
 656                 }
 657                 break;
 658         case OTG_STATE_B_IDLE:
 659                 if (otg_bsess_vld && (intr_sts & USBi_PCI) && port_conn) {
 660                         fsm->b_sess_vld = 1;
 661                         ci_otg_queue_work(ci);
 662                 }
 663                 break;
 664         case OTG_STATE_B_PERIPHERAL:
 665                 if ((intr_sts & USBi_SLI) && port_conn && otg_bsess_vld) {
 666                         ci_otg_add_timer(ci, B_AIDL_BDIS);
 667                 } else if (intr_sts & USBi_PCI) {
 668                         ci_otg_del_timer(ci, B_AIDL_BDIS);
 669                         if (fsm->a_bus_suspend == 1)
 670                                 fsm->a_bus_suspend = 0;
 671                 }
 672                 break;
 673         case OTG_STATE_B_HOST:
 674                 if ((intr_sts & USBi_PCI) && !port_conn) {
 675                         fsm->a_conn = 0;
 676                         fsm->b_bus_req = 0;
 677                         ci_otg_queue_work(ci);
 678                 }
 679                 break;
 680         case OTG_STATE_A_PERIPHERAL:
 681                 if (intr_sts & USBi_SLI) {
 682                          fsm->b_bus_suspend = 1;
 683                         /*
 684                          * Init a timer to know how long this suspend
 685                          * will continue, if time out, indicates B no longer
 686                          * wants to be host role
 687                          */
 688                          ci_otg_add_timer(ci, A_BIDL_ADIS);
 689                 }
 690
 691                 if (intr_sts & USBi_URI)
 692                         ci_otg_del_timer(ci, A_BIDL_ADIS);
 693
 694                 if (intr_sts & USBi_PCI) {
 695                         if (fsm->b_bus_suspend == 1) {
 696                                 ci_otg_del_timer(ci, A_BIDL_ADIS);
 697                                 fsm->b_bus_suspend = 0;
 698                         }
 699                 }
 700                 break;
 701         case OTG_STATE_A_SUSPEND:
 702                 if ((intr_sts & USBi_PCI) && !port_conn) {
 703                         fsm->b_conn = 0;
 704
 705                         /* if gadget driver is binded */
 706                         if (ci->driver) {
 707                                 /* A device to be peripheral mode */
 708                                 ci->gadget.is_a_peripheral = 1;
 709                         }
 710                         ci_otg_queue_work(ci);
 711                 }
 712                 break;
 713         case OTG_STATE_A_HOST:
 714                 if ((intr_sts & USBi_PCI) && !port_conn) {
 715                         fsm->b_conn = 0;
 716                         ci_otg_queue_work(ci);
 717                 }
 718                 break;
 719         case OTG_STATE_B_WAIT_ACON:
 720                 if ((intr_sts & USBi_PCI) && port_conn) {
 721                         fsm->a_conn = 1;
 722                         ci_otg_queue_work(ci);
 723                 }
 724                 break;
 725         default:
 726                 break;
 727         }
 728 }
 729
 730 /*
 731  * ci_otg_irq - otg fsm related irq handling
 732  * and also update otg fsm variable by monitoring usb host and udc
 733  * state change interrupts.
 734  * @ci: ci_hdrc
 735  */
 736 irqreturn_t ci_otg_fsm_irq(struct ci_hdrc *ci)
 737 {
 738         irqreturn_t retval =  IRQ_NONE;
 739         u32 otgsc, otg_int_src = 0;
 740         struct otg_fsm *fsm = &ci->fsm;
 741
 742         otgsc = hw_read_otgsc(ci, ~0);
 743         otg_int_src = otgsc & OTGSC_INT_STATUS_BITS & (otgsc >> 8);
 744         fsm->id = (otgsc & OTGSC_ID) ? 1 : 0;
 745
 746         if (otg_int_src) {
 747                 if (otg_int_src & OTGSC_DPIS) {
 748                         hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
 749                         fsm->a_srp_det = 1;
 750                         fsm->a_bus_drop = 0;
 751                 } else if (otg_int_src & OTGSC_IDIS) {
 752                         hw_write_otgsc(ci, OTGSC_IDIS, OTGSC_IDIS);
 753                         if (fsm->id == 0) {
 754                                 fsm->a_bus_drop = 0;
 755                                 fsm->a_bus_req = 1;
 756                                 ci->id_event = true;
 757                         }
 758                 } else if (otg_int_src & OTGSC_BSVIS) {
 759                         hw_write_otgsc(ci, OTGSC_BSVIS, OTGSC_BSVIS);
 760                         if (otgsc & OTGSC_BSV) {
 761                                 fsm->b_sess_vld = 1;
 762                                 ci_otg_del_timer(ci, B_SSEND_SRP);
 763                                 ci_otg_del_timer(ci, B_SRP_FAIL);
 764                                 fsm->b_ssend_srp = 0;
 765                         } else {
 766                                 fsm->b_sess_vld = 0;
 767                                 if (fsm->id)
 768                                         ci_otg_add_timer(ci, B_SSEND_SRP);
 769                         }
 770                 } else if (otg_int_src & OTGSC_AVVIS) {
 771                         hw_write_otgsc(ci, OTGSC_AVVIS, OTGSC_AVVIS);
 772                         if (otgsc & OTGSC_AVV) {
 773                                 fsm->a_vbus_vld = 1;
 774                         } else {
 775                                 fsm->a_vbus_vld = 0;
 776                                 fsm->b_conn = 0;
 777                         }
 778                 }
 779                 ci_otg_queue_work(ci);
 780                 return IRQ_HANDLED;
 781         }
 782
 783         ci_otg_fsm_event(ci);
 784
 785         return retval;
 786 }
 787
 788 void ci_hdrc_otg_fsm_start(struct ci_hdrc *ci)
 789 {
 790         ci_otg_queue_work(ci);
 791 }
 792
 793 int ci_hdrc_otg_fsm_init(struct ci_hdrc *ci)
 794 {
 795         int retval = 0;
 796
 797         if (ci->phy)
 798                 ci->otg.phy = ci->phy;
 799         else
 800                 ci->otg.usb_phy = ci->usb_phy;
 801
 802         ci->otg.gadget = &ci->gadget;
 803         ci->fsm.otg = &ci->otg;
 804         ci->fsm.power_up = 1;
 805         ci->fsm.id = hw_read_otgsc(ci, OTGSC_ID) ? 1 : 0;
 806         ci->fsm.otg->state = OTG_STATE_UNDEFINED;
 807         ci->fsm.ops = &ci_otg_ops;
 808         ci->gadget.hnp_polling_support = 1;
 809         ci->fsm.host_req_flag = devm_kzalloc(ci->dev, 1, GFP_KERNEL);
 810         if (!ci->fsm.host_req_flag)
 811                 return -ENOMEM;
 812
 813         mutex_init(&ci->fsm.lock);
 814
 815         retval = ci_otg_init_timers(ci);
 816         if (retval) {
 817                 dev_err(ci->dev, "Couldn't init OTG timers\n");
 818                 return retval;
 819         }
 820         ci->enabled_otg_timer_bits = 0;
 821         ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
 822
 823         retval = sysfs_create_group(&ci->dev->kobj, &inputs_attr_group);
 824         if (retval < 0) {
 825                 dev_dbg(ci->dev,
 826                         "Can't register sysfs attr group: %d\n", retval);
 827                 return retval;
 828         }
 829
 830         /* Enable A vbus valid irq */
 831         hw_write_otgsc(ci, OTGSC_AVVIE, OTGSC_AVVIE);
 832
 833         if (ci->fsm.id) {
 834                 ci->fsm.b_ssend_srp =
 835                         hw_read_otgsc(ci, OTGSC_BSV) ? 0 : 1;
 836                 ci->fsm.b_sess_vld =
 837                         hw_read_otgsc(ci, OTGSC_BSV) ? 1 : 0;
 838                 /* Enable BSV irq */
 839                 hw_write_otgsc(ci, OTGSC_BSVIE, OTGSC_BSVIE);
 840         }
 841
 842         return 0;
 843 }
 844
 845 void ci_hdrc_otg_fsm_remove(struct ci_hdrc *ci)
 846 {
 847         sysfs_remove_group(&ci->dev->kobj, &inputs_attr_group);
 848 }