drivers/usb/phy/phy-mv-usb.c

   1 /*
   2  * Copyright (C) 2011 Marvell International Ltd. All rights reserved.
   3  * Author: Chao Xie <chao.xie@marvell.com>
   4  *         Neil Zhang <zhangwm@marvell.com>
   5  *
   6  * This program is free software; you can redistribute  it and/or modify it
   7  * under  the terms of  the GNU General  Public License as published by the
   8  * Free Software Foundation;  either version 2 of the  License, or (at your
   9  * option) any later version.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/kernel.h>
  14 #include <linux/init.h>
  15 #include <linux/io.h>
  16 #include <linux/uaccess.h>
  17 #include <linux/device.h>
  18 #include <linux/proc_fs.h>
  19 #include <linux/clk.h>
  20 #include <linux/workqueue.h>
  21 #include <linux/platform_device.h>
  22
  23 #include <linux/usb.h>
  24 #include <linux/usb/ch9.h>
  25 #include <linux/usb/otg.h>
  26 #include <linux/usb/gadget.h>
  27 #include <linux/usb/hcd.h>
  28 #include <linux/platform_data/mv_usb.h>
  29
  30 #include "phy-mv-usb.h"
  31
  32 #define DRIVER_DESC     "Marvell USB OTG transceiver driver"
  33 #define DRIVER_VERSION  "Jan 20, 2010"
  34
  35 MODULE_DESCRIPTION(DRIVER_DESC);
  36 MODULE_VERSION(DRIVER_VERSION);
  37 MODULE_LICENSE("GPL");
  38
  39 static const char driver_name[] = "mv-otg";
  40
  41 static char *state_string[] = {
  42         "undefined",
  43         "b_idle",
  44         "b_srp_init",
  45         "b_peripheral",
  46         "b_wait_acon",
  47         "b_host",
  48         "a_idle",
  49         "a_wait_vrise",
  50         "a_wait_bcon",
  51         "a_host",
  52         "a_suspend",
  53         "a_peripheral",
  54         "a_wait_vfall",
  55         "a_vbus_err"
  56 };
  57
  58 static int mv_otg_set_vbus(struct usb_otg *otg, bool on)
  59 {
  60         struct mv_otg *mvotg = container_of(otg->phy, struct mv_otg, phy);
  61         if (mvotg->pdata->set_vbus == NULL)
  62                 return -ENODEV;
  63
  64         return mvotg->pdata->set_vbus(on);
  65 }
  66
  67 static int mv_otg_set_host(struct usb_otg *otg,
  68                            struct usb_bus *host)
  69 {
  70         otg->host = host;
  71
  72         return 0;
  73 }
  74
  75 static int mv_otg_set_peripheral(struct usb_otg *otg,
  76                                  struct usb_gadget *gadget)
  77 {
  78         otg->gadget = gadget;
  79
  80         return 0;
  81 }
  82
  83 static void mv_otg_run_state_machine(struct mv_otg *mvotg,
  84                                      unsigned long delay)
  85 {
  86         dev_dbg(&mvotg->pdev->dev, "transceiver is updated\n");
  87         if (!mvotg->qwork)
  88                 return;
  89
  90         queue_delayed_work(mvotg->qwork, &mvotg->work, delay);
  91 }
  92
  93 static void mv_otg_timer_await_bcon(unsigned long data)
  94 {
  95         struct mv_otg *mvotg = (struct mv_otg *) data;
  96
  97         mvotg->otg_ctrl.a_wait_bcon_timeout = 1;
  98
  99         dev_info(&mvotg->pdev->dev, "B Device No Response!\n");
 100
 101         if (spin_trylock(&mvotg->wq_lock)) {
 102                 mv_otg_run_state_machine(mvotg, 0);
 103                 spin_unlock(&mvotg->wq_lock);
 104         }
 105 }
 106
 107 static int mv_otg_cancel_timer(struct mv_otg *mvotg, unsigned int id)
 108 {
 109         struct timer_list *timer;
 110
 111         if (id >= OTG_TIMER_NUM)
 112                 return -EINVAL;
 113
 114         timer = &mvotg->otg_ctrl.timer[id];
 115
 116         if (timer_pending(timer))
 117                 del_timer(timer);
 118
 119         return 0;
 120 }
 121
 122 static int mv_otg_set_timer(struct mv_otg *mvotg, unsigned int id,
 123                             unsigned long interval,
 124                             void (*callback) (unsigned long))
 125 {
 126         struct timer_list *timer;
 127
 128         if (id >= OTG_TIMER_NUM)
 129                 return -EINVAL;
 130
 131         timer = &mvotg->otg_ctrl.timer[id];
 132         if (timer_pending(timer)) {
 133                 dev_err(&mvotg->pdev->dev, "Timer%d is already running\n", id);
 134                 return -EBUSY;
 135         }
 136
 137         init_timer(timer);
 138         timer->data = (unsigned long) mvotg;
 139         timer->function = callback;
 140         timer->expires = jiffies + interval;
 141         add_timer(timer);
 142
 143         return 0;
 144 }
 145
 146 static int mv_otg_reset(struct mv_otg *mvotg)
 147 {
 148         unsigned int loops;
 149         u32 tmp;
 150
 151         /* Stop the controller */
 152         tmp = readl(&mvotg->op_regs->usbcmd);
 153         tmp &= ~USBCMD_RUN_STOP;
 154         writel(tmp, &mvotg->op_regs->usbcmd);
 155
 156         /* Reset the controller to get default values */
 157         writel(USBCMD_CTRL_RESET, &mvotg->op_regs->usbcmd);
 158
 159         loops = 500;
 160         while (readl(&mvotg->op_regs->usbcmd) & USBCMD_CTRL_RESET) {
 161                 if (loops == 0) {
 162                         dev_err(&mvotg->pdev->dev,
 163                                 "Wait for RESET completed TIMEOUT\n");
 164                         return -ETIMEDOUT;
 165                 }
 166                 loops--;
 167                 udelay(20);
 168         }
 169
 170         writel(0x0, &mvotg->op_regs->usbintr);
 171         tmp = readl(&mvotg->op_regs->usbsts);
 172         writel(tmp, &mvotg->op_regs->usbsts);
 173
 174         return 0;
 175 }
 176
 177 static void mv_otg_init_irq(struct mv_otg *mvotg)
 178 {
 179         u32 otgsc;
 180
 181         mvotg->irq_en = OTGSC_INTR_A_SESSION_VALID
 182             | OTGSC_INTR_A_VBUS_VALID;
 183         mvotg->irq_status = OTGSC_INTSTS_A_SESSION_VALID
 184             | OTGSC_INTSTS_A_VBUS_VALID;
 185
 186         if (mvotg->pdata->vbus == NULL) {
 187                 mvotg->irq_en |= OTGSC_INTR_B_SESSION_VALID
 188                     | OTGSC_INTR_B_SESSION_END;
 189                 mvotg->irq_status |= OTGSC_INTSTS_B_SESSION_VALID
 190                     | OTGSC_INTSTS_B_SESSION_END;
 191         }
 192
 193         if (mvotg->pdata->id == NULL) {
 194                 mvotg->irq_en |= OTGSC_INTR_USB_ID;
 195                 mvotg->irq_status |= OTGSC_INTSTS_USB_ID;
 196         }
 197
 198         otgsc = readl(&mvotg->op_regs->otgsc);
 199         otgsc |= mvotg->irq_en;
 200         writel(otgsc, &mvotg->op_regs->otgsc);
 201 }
 202
 203 static void mv_otg_start_host(struct mv_otg *mvotg, int on)
 204 {
 205 #ifdef CONFIG_USB
 206         struct usb_otg *otg = mvotg->phy.otg;
 207         struct usb_hcd *hcd;
 208
 209         if (!otg->host)
 210                 return;
 211
 212         dev_info(&mvotg->pdev->dev, "%s host\n", on ? "start" : "stop");
 213
 214         hcd = bus_to_hcd(otg->host);
 215
 216         if (on)
 217                 usb_add_hcd(hcd, hcd->irq, IRQF_SHARED);
 218         else
 219                 usb_remove_hcd(hcd);
 220 #endif /* CONFIG_USB */
 221 }
 222
 223 static void mv_otg_start_periphrals(struct mv_otg *mvotg, int on)
 224 {
 225         struct usb_otg *otg = mvotg->phy.otg;
 226
 227         if (!otg->gadget)
 228                 return;
 229
 230         dev_info(mvotg->phy.dev, "gadget %s\n", on ? "on" : "off");
 231
 232         if (on)
 233                 usb_gadget_vbus_connect(otg->gadget);
 234         else
 235                 usb_gadget_vbus_disconnect(otg->gadget);
 236 }
 237
 238 static void otg_clock_enable(struct mv_otg *mvotg)
 239 {
 240         clk_prepare_enable(mvotg->clk);
 241 }
 242
 243 static void otg_clock_disable(struct mv_otg *mvotg)
 244 {
 245         clk_disable_unprepare(mvotg->clk);
 246 }
 247
 248 static int mv_otg_enable_internal(struct mv_otg *mvotg)
 249 {
 250         int retval = 0;
 251
 252         if (mvotg->active)
 253                 return 0;
 254
 255         dev_dbg(&mvotg->pdev->dev, "otg enabled\n");
 256
 257         otg_clock_enable(mvotg);
 258         if (mvotg->pdata->phy_init) {
 259                 retval = mvotg->pdata->phy_init(mvotg->phy_regs);
 260                 if (retval) {
 261                         dev_err(&mvotg->pdev->dev,
 262                                 "init phy error %d\n", retval);
 263                         otg_clock_disable(mvotg);
 264                         return retval;
 265                 }
 266         }
 267         mvotg->active = 1;
 268
 269         return 0;
 270
 271 }
 272
 273 static int mv_otg_enable(struct mv_otg *mvotg)
 274 {
 275         if (mvotg->clock_gating)
 276                 return mv_otg_enable_internal(mvotg);
 277
 278         return 0;
 279 }
 280
 281 static void mv_otg_disable_internal(struct mv_otg *mvotg)
 282 {
 283         if (mvotg->active) {
 284                 dev_dbg(&mvotg->pdev->dev, "otg disabled\n");
 285                 if (mvotg->pdata->phy_deinit)
 286                         mvotg->pdata->phy_deinit(mvotg->phy_regs);
 287                 otg_clock_disable(mvotg);
 288                 mvotg->active = 0;
 289         }
 290 }
 291
 292 static void mv_otg_disable(struct mv_otg *mvotg)
 293 {
 294         if (mvotg->clock_gating)
 295                 mv_otg_disable_internal(mvotg);
 296 }
 297
 298 static void mv_otg_update_inputs(struct mv_otg *mvotg)
 299 {
 300         struct mv_otg_ctrl *otg_ctrl = &mvotg->otg_ctrl;
 301         u32 otgsc;
 302
 303         otgsc = readl(&mvotg->op_regs->otgsc);
 304
 305         if (mvotg->pdata->vbus) {
 306                 if (mvotg->pdata->vbus->poll() == VBUS_HIGH) {
 307                         otg_ctrl->b_sess_vld = 1;
 308                         otg_ctrl->b_sess_end = 0;
 309                 } else {
 310                         otg_ctrl->b_sess_vld = 0;
 311                         otg_ctrl->b_sess_end = 1;
 312                 }
 313         } else {
 314                 otg_ctrl->b_sess_vld = !!(otgsc & OTGSC_STS_B_SESSION_VALID);
 315                 otg_ctrl->b_sess_end = !!(otgsc & OTGSC_STS_B_SESSION_END);
 316         }
 317
 318         if (mvotg->pdata->id)
 319                 otg_ctrl->id = !!mvotg->pdata->id->poll();
 320         else
 321                 otg_ctrl->id = !!(otgsc & OTGSC_STS_USB_ID);
 322
 323         if (mvotg->pdata->otg_force_a_bus_req && !otg_ctrl->id)
 324                 otg_ctrl->a_bus_req = 1;
 325
 326         otg_ctrl->a_sess_vld = !!(otgsc & OTGSC_STS_A_SESSION_VALID);
 327         otg_ctrl->a_vbus_vld = !!(otgsc & OTGSC_STS_A_VBUS_VALID);
 328
 329         dev_dbg(&mvotg->pdev->dev, "%s: ", __func__);
 330         dev_dbg(&mvotg->pdev->dev, "id %d\n", otg_ctrl->id);
 331         dev_dbg(&mvotg->pdev->dev, "b_sess_vld %d\n", otg_ctrl->b_sess_vld);
 332         dev_dbg(&mvotg->pdev->dev, "b_sess_end %d\n", otg_ctrl->b_sess_end);
 333         dev_dbg(&mvotg->pdev->dev, "a_vbus_vld %d\n", otg_ctrl->a_vbus_vld);
 334         dev_dbg(&mvotg->pdev->dev, "a_sess_vld %d\n", otg_ctrl->a_sess_vld);
 335 }
 336
 337 static void mv_otg_update_state(struct mv_otg *mvotg)
 338 {
 339         struct mv_otg_ctrl *otg_ctrl = &mvotg->otg_ctrl;
 340         struct usb_phy *phy = &mvotg->phy;
 341         int old_state = phy->state;
 342
 343         switch (old_state) {
 344         case OTG_STATE_UNDEFINED:
 345                 phy->state = OTG_STATE_B_IDLE;
 346                 /* FALL THROUGH */
 347         case OTG_STATE_B_IDLE:
 348                 if (otg_ctrl->id == 0)
 349                         phy->state = OTG_STATE_A_IDLE;
 350                 else if (otg_ctrl->b_sess_vld)
 351                         phy->state = OTG_STATE_B_PERIPHERAL;
 352                 break;
 353         case OTG_STATE_B_PERIPHERAL:
 354                 if (!otg_ctrl->b_sess_vld || otg_ctrl->id == 0)
 355                         phy->state = OTG_STATE_B_IDLE;
 356                 break;
 357         case OTG_STATE_A_IDLE:
 358                 if (otg_ctrl->id)
 359                         phy->state = OTG_STATE_B_IDLE;
 360                 else if (!(otg_ctrl->a_bus_drop) &&
 361                          (otg_ctrl->a_bus_req || otg_ctrl->a_srp_det))
 362                         phy->state = OTG_STATE_A_WAIT_VRISE;
 363                 break;
 364         case OTG_STATE_A_WAIT_VRISE:
 365                 if (otg_ctrl->a_vbus_vld)
 366                         phy->state = OTG_STATE_A_WAIT_BCON;
 367                 break;
 368         case OTG_STATE_A_WAIT_BCON:
 369                 if (otg_ctrl->id || otg_ctrl->a_bus_drop
 370                     || otg_ctrl->a_wait_bcon_timeout) {
 371                         mv_otg_cancel_timer(mvotg, A_WAIT_BCON_TIMER);
 372                         mvotg->otg_ctrl.a_wait_bcon_timeout = 0;
 373                         phy->state = OTG_STATE_A_WAIT_VFALL;
 374                         otg_ctrl->a_bus_req = 0;
 375                 } else if (!otg_ctrl->a_vbus_vld) {
 376                         mv_otg_cancel_timer(mvotg, A_WAIT_BCON_TIMER);
 377                         mvotg->otg_ctrl.a_wait_bcon_timeout = 0;
 378                         phy->state = OTG_STATE_A_VBUS_ERR;
 379                 } else if (otg_ctrl->b_conn) {
 380                         mv_otg_cancel_timer(mvotg, A_WAIT_BCON_TIMER);
 381                         mvotg->otg_ctrl.a_wait_bcon_timeout = 0;
 382                         phy->state = OTG_STATE_A_HOST;
 383                 }
 384                 break;
 385         case OTG_STATE_A_HOST:
 386                 if (otg_ctrl->id || !otg_ctrl->b_conn
 387                     || otg_ctrl->a_bus_drop)
 388                         phy->state = OTG_STATE_A_WAIT_BCON;
 389                 else if (!otg_ctrl->a_vbus_vld)
 390                         phy->state = OTG_STATE_A_VBUS_ERR;
 391                 break;
 392         case OTG_STATE_A_WAIT_VFALL:
 393                 if (otg_ctrl->id
 394                     || (!otg_ctrl->b_conn && otg_ctrl->a_sess_vld)
 395                     || otg_ctrl->a_bus_req)
 396                         phy->state = OTG_STATE_A_IDLE;
 397                 break;
 398         case OTG_STATE_A_VBUS_ERR:
 399                 if (otg_ctrl->id || otg_ctrl->a_clr_err
 400                     || otg_ctrl->a_bus_drop) {
 401                         otg_ctrl->a_clr_err = 0;
 402                         phy->state = OTG_STATE_A_WAIT_VFALL;
 403                 }
 404                 break;
 405         default:
 406                 break;
 407         }
 408 }
 409
 410 static void mv_otg_work(struct work_struct *work)
 411 {
 412         struct mv_otg *mvotg;
 413         struct usb_phy *phy;
 414         struct usb_otg *otg;
 415         int old_state;
 416
 417         mvotg = container_of(to_delayed_work(work), struct mv_otg, work);
 418
 419 run:
 420         /* work queue is single thread, or we need spin_lock to protect */
 421         phy = &mvotg->phy;
 422         otg = phy->otg;
 423         old_state = phy->state;
 424
 425         if (!mvotg->active)
 426                 return;
 427
 428         mv_otg_update_inputs(mvotg);
 429         mv_otg_update_state(mvotg);
 430
 431         if (old_state != phy->state) {
 432                 dev_info(&mvotg->pdev->dev, "change from state %s to %s\n",
 433                          state_string[old_state],
 434                          state_string[phy->state]);
 435
 436                 switch (phy->state) {
 437                 case OTG_STATE_B_IDLE:
 438                         otg->default_a = 0;
 439                         if (old_state == OTG_STATE_B_PERIPHERAL)
 440                                 mv_otg_start_periphrals(mvotg, 0);
 441                         mv_otg_reset(mvotg);
 442                         mv_otg_disable(mvotg);
 443                         break;
 444                 case OTG_STATE_B_PERIPHERAL:
 445                         mv_otg_enable(mvotg);
 446                         mv_otg_start_periphrals(mvotg, 1);
 447                         break;
 448                 case OTG_STATE_A_IDLE:
 449                         otg->default_a = 1;
 450                         mv_otg_enable(mvotg);
 451                         if (old_state == OTG_STATE_A_WAIT_VFALL)
 452                                 mv_otg_start_host(mvotg, 0);
 453                         mv_otg_reset(mvotg);
 454                         break;
 455                 case OTG_STATE_A_WAIT_VRISE:
 456                         mv_otg_set_vbus(otg, 1);
 457                         break;
 458                 case OTG_STATE_A_WAIT_BCON:
 459                         if (old_state != OTG_STATE_A_HOST)
 460                                 mv_otg_start_host(mvotg, 1);
 461                         mv_otg_set_timer(mvotg, A_WAIT_BCON_TIMER,
 462                                          T_A_WAIT_BCON,
 463                                          mv_otg_timer_await_bcon);
 464                         /*
 465                          * Now, we directly enter A_HOST. So set b_conn = 1
 466                          * here. In fact, it need host driver to notify us.
 467                          */
 468                         mvotg->otg_ctrl.b_conn = 1;
 469                         break;
 470                 case OTG_STATE_A_HOST:
 471                         break;
 472                 case OTG_STATE_A_WAIT_VFALL:
 473                         /*
 474                          * Now, we has exited A_HOST. So set b_conn = 0
 475                          * here. In fact, it need host driver to notify us.
 476                          */
 477                         mvotg->otg_ctrl.b_conn = 0;
 478                         mv_otg_set_vbus(otg, 0);
 479                         break;
 480                 case OTG_STATE_A_VBUS_ERR:
 481                         break;
 482                 default:
 483                         break;
 484                 }
 485                 goto run;
 486         }
 487 }
 488
 489 static irqreturn_t mv_otg_irq(int irq, void *dev)
 490 {
 491         struct mv_otg *mvotg = dev;
 492         u32 otgsc;
 493
 494         otgsc = readl(&mvotg->op_regs->otgsc);
 495         writel(otgsc, &mvotg->op_regs->otgsc);
 496
 497         /*
 498          * if we have vbus, then the vbus detection for B-device
 499          * will be done by mv_otg_inputs_irq().
 500          */
 501         if (mvotg->pdata->vbus)
 502                 if ((otgsc & OTGSC_STS_USB_ID) &&
 503                     !(otgsc & OTGSC_INTSTS_USB_ID))
 504                         return IRQ_NONE;
 505
 506         if ((otgsc & mvotg->irq_status) == 0)
 507                 return IRQ_NONE;
 508
 509         mv_otg_run_state_machine(mvotg, 0);
 510
 511         return IRQ_HANDLED;
 512 }
 513
 514 static irqreturn_t mv_otg_inputs_irq(int irq, void *dev)
 515 {
 516         struct mv_otg *mvotg = dev;
 517
 518         /* The clock may disabled at this time */
 519         if (!mvotg->active) {
 520                 mv_otg_enable(mvotg);
 521                 mv_otg_init_irq(mvotg);
 522         }
 523
 524         mv_otg_run_state_machine(mvotg, 0);
 525
 526         return IRQ_HANDLED;
 527 }
 528
 529 static ssize_t
 530 get_a_bus_req(struct device *dev, struct device_attribute *attr, char *buf)
 531 {
 532         struct mv_otg *mvotg = dev_get_drvdata(dev);
 533         return scnprintf(buf, PAGE_SIZE, "%d\n",
 534                          mvotg->otg_ctrl.a_bus_req);
 535 }
 536
 537 static ssize_t
 538 set_a_bus_req(struct device *dev, struct device_attribute *attr,
 539               const char *buf, size_t count)
 540 {
 541         struct mv_otg *mvotg = dev_get_drvdata(dev);
 542
 543         if (count > 2)
 544                 return -1;
 545
 546         /* We will use this interface to change to A device */
 547         if (mvotg->phy.state != OTG_STATE_B_IDLE
 548             && mvotg->phy.state != OTG_STATE_A_IDLE)
 549                 return -1;
 550
 551         /* The clock may disabled and we need to set irq for ID detected */
 552         mv_otg_enable(mvotg);
 553         mv_otg_init_irq(mvotg);
 554
 555         if (buf[0] == '1') {
 556                 mvotg->otg_ctrl.a_bus_req = 1;
 557                 mvotg->otg_ctrl.a_bus_drop = 0;
 558                 dev_dbg(&mvotg->pdev->dev,
 559                         "User request: a_bus_req = 1\n");
 560
 561                 if (spin_trylock(&mvotg->wq_lock)) {
 562                         mv_otg_run_state_machine(mvotg, 0);
 563                         spin_unlock(&mvotg->wq_lock);
 564                 }
 565         }
 566
 567         return count;
 568 }
 569
 570 static DEVICE_ATTR(a_bus_req, S_IRUGO | S_IWUSR, get_a_bus_req,
 571                    set_a_bus_req);
 572
 573 static ssize_t
 574 set_a_clr_err(struct device *dev, struct device_attribute *attr,
 575               const char *buf, size_t count)
 576 {
 577         struct mv_otg *mvotg = dev_get_drvdata(dev);
 578         if (!mvotg->phy.otg->default_a)
 579                 return -1;
 580
 581         if (count > 2)
 582                 return -1;
 583
 584         if (buf[0] == '1') {
 585                 mvotg->otg_ctrl.a_clr_err = 1;
 586                 dev_dbg(&mvotg->pdev->dev,
 587                         "User request: a_clr_err = 1\n");
 588         }
 589
 590         if (spin_trylock(&mvotg->wq_lock)) {
 591                 mv_otg_run_state_machine(mvotg, 0);
 592                 spin_unlock(&mvotg->wq_lock);
 593         }
 594
 595         return count;
 596 }
 597
 598 static DEVICE_ATTR(a_clr_err, S_IWUSR, NULL, set_a_clr_err);
 599
 600 static ssize_t
 601 get_a_bus_drop(struct device *dev, struct device_attribute *attr,
 602                char *buf)
 603 {
 604         struct mv_otg *mvotg = dev_get_drvdata(dev);
 605         return scnprintf(buf, PAGE_SIZE, "%d\n",
 606                          mvotg->otg_ctrl.a_bus_drop);
 607 }
 608
 609 static ssize_t
 610 set_a_bus_drop(struct device *dev, struct device_attribute *attr,
 611                const char *buf, size_t count)
 612 {
 613         struct mv_otg *mvotg = dev_get_drvdata(dev);
 614         if (!mvotg->phy.otg->default_a)
 615                 return -1;
 616
 617         if (count > 2)
 618                 return -1;
 619
 620         if (buf[0] == '0') {
 621                 mvotg->otg_ctrl.a_bus_drop = 0;
 622                 dev_dbg(&mvotg->pdev->dev,
 623                         "User request: a_bus_drop = 0\n");
 624         } else if (buf[0] == '1') {
 625                 mvotg->otg_ctrl.a_bus_drop = 1;
 626                 mvotg->otg_ctrl.a_bus_req = 0;
 627                 dev_dbg(&mvotg->pdev->dev,
 628                         "User request: a_bus_drop = 1\n");
 629                 dev_dbg(&mvotg->pdev->dev,
 630                         "User request: and a_bus_req = 0\n");
 631         }
 632
 633         if (spin_trylock(&mvotg->wq_lock)) {
 634                 mv_otg_run_state_machine(mvotg, 0);
 635                 spin_unlock(&mvotg->wq_lock);
 636         }
 637
 638         return count;
 639 }
 640
 641 static DEVICE_ATTR(a_bus_drop, S_IRUGO | S_IWUSR,
 642                    get_a_bus_drop, set_a_bus_drop);
 643
 644 static struct attribute *inputs_attrs[] = {
 645         &dev_attr_a_bus_req.attr,
 646         &dev_attr_a_clr_err.attr,
 647         &dev_attr_a_bus_drop.attr,
 648         NULL,
 649 };
 650
 651 static struct attribute_group inputs_attr_group = {
 652         .name = "inputs",
 653         .attrs = inputs_attrs,
 654 };
 655
 656 int mv_otg_remove(struct platform_device *pdev)
 657 {
 658         struct mv_otg *mvotg = platform_get_drvdata(pdev);
 659
 660         sysfs_remove_group(&mvotg->pdev->dev.kobj, &inputs_attr_group);
 661
 662         if (mvotg->qwork) {
 663                 flush_workqueue(mvotg->qwork);
 664                 destroy_workqueue(mvotg->qwork);
 665         }
 666
 667         mv_otg_disable(mvotg);
 668
 669         usb_remove_phy(&mvotg->phy);
 670
 671         return 0;
 672 }
 673
 674 static int mv_otg_probe(struct platform_device *pdev)
 675 {
 676         struct mv_usb_platform_data *pdata = pdev->dev.platform_data;
 677         struct mv_otg *mvotg;
 678         struct usb_otg *otg;
 679         struct resource *r;
 680         int retval = 0, i;
 681
 682         if (pdata == NULL) {
 683                 dev_err(&pdev->dev, "failed to get platform data\n");
 684                 return -ENODEV;
 685         }
 686
 687         mvotg = devm_kzalloc(&pdev->dev, sizeof(*mvotg), GFP_KERNEL);
 688         if (!mvotg) {
 689                 dev_err(&pdev->dev, "failed to allocate memory!\n");
 690                 return -ENOMEM;
 691         }
 692
 693         otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);
 694         if (!otg)
 695                 return -ENOMEM;
 696
 697         platform_set_drvdata(pdev, mvotg);
 698
 699         mvotg->pdev = pdev;
 700         mvotg->pdata = pdata;
 701
 702         mvotg->clk = devm_clk_get(&pdev->dev, NULL);
 703         if (IS_ERR(mvotg->clk))
 704                 return PTR_ERR(mvotg->clk);
 705
 706         mvotg->qwork = create_singlethread_workqueue("mv_otg_queue");
 707         if (!mvotg->qwork) {
 708                 dev_dbg(&pdev->dev, "cannot create workqueue for OTG\n");
 709                 return -ENOMEM;
 710         }
 711
 712         INIT_DELAYED_WORK(&mvotg->work, mv_otg_work);
 713
 714         /* OTG common part */
 715         mvotg->pdev = pdev;
 716         mvotg->phy.dev = &pdev->dev;
 717         mvotg->phy.otg = otg;
 718         mvotg->phy.label = driver_name;
 719         mvotg->phy.state = OTG_STATE_UNDEFINED;
 720
 721         otg->phy = &mvotg->phy;
 722         otg->set_host = mv_otg_set_host;
 723         otg->set_peripheral = mv_otg_set_peripheral;
 724         otg->set_vbus = mv_otg_set_vbus;
 725
 726         for (i = 0; i < OTG_TIMER_NUM; i++)
 727                 init_timer(&mvotg->otg_ctrl.timer[i]);
 728
 729         r = platform_get_resource_byname(mvotg->pdev,
 730                                          IORESOURCE_MEM, "phyregs");
 731         if (r == NULL) {
 732                 dev_err(&pdev->dev, "no phy I/O memory resource defined\n");
 733                 retval = -ENODEV;
 734                 goto err_destroy_workqueue;
 735         }
 736
 737         mvotg->phy_regs = devm_ioremap(&pdev->dev, r->start, resource_size(r));
 738         if (mvotg->phy_regs == NULL) {
 739                 dev_err(&pdev->dev, "failed to map phy I/O memory\n");
 740                 retval = -EFAULT;
 741                 goto err_destroy_workqueue;
 742         }
 743
 744         r = platform_get_resource_byname(mvotg->pdev,
 745                                          IORESOURCE_MEM, "capregs");
 746         if (r == NULL) {
 747                 dev_err(&pdev->dev, "no I/O memory resource defined\n");
 748                 retval = -ENODEV;
 749                 goto err_destroy_workqueue;
 750         }
 751
 752         mvotg->cap_regs = devm_ioremap(&pdev->dev, r->start, resource_size(r));
 753         if (mvotg->cap_regs == NULL) {
 754                 dev_err(&pdev->dev, "failed to map I/O memory\n");
 755                 retval = -EFAULT;
 756                 goto err_destroy_workqueue;
 757         }
 758
 759         /* we will acces controller register, so enable the udc controller */
 760         retval = mv_otg_enable_internal(mvotg);
 761         if (retval) {
 762                 dev_err(&pdev->dev, "mv otg enable error %d\n", retval);
 763                 goto err_destroy_workqueue;
 764         }
 765
 766         mvotg->op_regs =
 767                 (struct mv_otg_regs __iomem *) ((unsigned long) mvotg->cap_regs
 768                         + (readl(mvotg->cap_regs) & CAPLENGTH_MASK));
 769
 770         if (pdata->id) {
 771                 retval = devm_request_threaded_irq(&pdev->dev, pdata->id->irq,
 772                                                 NULL, mv_otg_inputs_irq,
 773                                                 IRQF_ONESHOT, "id", mvotg);
 774                 if (retval) {
 775                         dev_info(&pdev->dev,
 776                                  "Failed to request irq for ID\n");
 777                         pdata->id = NULL;
 778                 }
 779         }
 780
 781         if (pdata->vbus) {
 782                 mvotg->clock_gating = 1;
 783                 retval = devm_request_threaded_irq(&pdev->dev, pdata->vbus->irq,
 784                                                 NULL, mv_otg_inputs_irq,
 785                                                 IRQF_ONESHOT, "vbus", mvotg);
 786                 if (retval) {
 787                         dev_info(&pdev->dev,
 788                                  "Failed to request irq for VBUS, "
 789                                  "disable clock gating\n");
 790                         mvotg->clock_gating = 0;
 791                         pdata->vbus = NULL;
 792                 }
 793         }
 794
 795         if (pdata->disable_otg_clock_gating)
 796                 mvotg->clock_gating = 0;
 797
 798         mv_otg_reset(mvotg);
 799         mv_otg_init_irq(mvotg);
 800
 801         r = platform_get_resource(mvotg->pdev, IORESOURCE_IRQ, 0);
 802         if (r == NULL) {
 803                 dev_err(&pdev->dev, "no IRQ resource defined\n");
 804                 retval = -ENODEV;
 805                 goto err_disable_clk;
 806         }
 807
 808         mvotg->irq = r->start;
 809         if (devm_request_irq(&pdev->dev, mvotg->irq, mv_otg_irq, IRQF_SHARED,
 810                         driver_name, mvotg)) {
 811                 dev_err(&pdev->dev, "Request irq %d for OTG failed\n",
 812                         mvotg->irq);
 813                 mvotg->irq = 0;
 814                 retval = -ENODEV;
 815                 goto err_disable_clk;
 816         }
 817
 818         retval = usb_add_phy(&mvotg->phy, USB_PHY_TYPE_USB2);
 819         if (retval < 0) {
 820                 dev_err(&pdev->dev, "can't register transceiver, %d\n",
 821                         retval);
 822                 goto err_disable_clk;
 823         }
 824
 825         retval = sysfs_create_group(&pdev->dev.kobj, &inputs_attr_group);
 826         if (retval < 0) {
 827                 dev_dbg(&pdev->dev,
 828                         "Can't register sysfs attr group: %d\n", retval);
 829                 goto err_remove_phy;
 830         }
 831
 832         spin_lock_init(&mvotg->wq_lock);
 833         if (spin_trylock(&mvotg->wq_lock)) {
 834                 mv_otg_run_state_machine(mvotg, 2 * HZ);
 835                 spin_unlock(&mvotg->wq_lock);
 836         }
 837
 838         dev_info(&pdev->dev,
 839                  "successful probe OTG device %s clock gating.\n",
 840                  mvotg->clock_gating ? "with" : "without");
 841
 842         return 0;
 843
 844 err_remove_phy:
 845         usb_remove_phy(&mvotg->phy);
 846 err_disable_clk:
 847         mv_otg_disable_internal(mvotg);
 848 err_destroy_workqueue:
 849         flush_workqueue(mvotg->qwork);
 850         destroy_workqueue(mvotg->qwork);
 851
 852         return retval;
 853 }
 854
 855 #ifdef CONFIG_PM
 856 static int mv_otg_suspend(struct platform_device *pdev, pm_message_t state)
 857 {
 858         struct mv_otg *mvotg = platform_get_drvdata(pdev);
 859
 860         if (mvotg->phy.state != OTG_STATE_B_IDLE) {
 861                 dev_info(&pdev->dev,
 862                          "OTG state is not B_IDLE, it is %d!\n",
 863                          mvotg->phy.state);
 864                 return -EAGAIN;
 865         }
 866
 867         if (!mvotg->clock_gating)
 868                 mv_otg_disable_internal(mvotg);
 869
 870         return 0;
 871 }
 872
 873 static int mv_otg_resume(struct platform_device *pdev)
 874 {
 875         struct mv_otg *mvotg = platform_get_drvdata(pdev);
 876         u32 otgsc;
 877
 878         if (!mvotg->clock_gating) {
 879                 mv_otg_enable_internal(mvotg);
 880
 881                 otgsc = readl(&mvotg->op_regs->otgsc);
 882                 otgsc |= mvotg->irq_en;
 883                 writel(otgsc, &mvotg->op_regs->otgsc);
 884
 885                 if (spin_trylock(&mvotg->wq_lock)) {
 886                         mv_otg_run_state_machine(mvotg, 0);
 887                         spin_unlock(&mvotg->wq_lock);
 888                 }
 889         }
 890         return 0;
 891 }
 892 #endif
 893
 894 static struct platform_driver mv_otg_driver = {
 895         .probe = mv_otg_probe,
 896         .remove = __exit_p(mv_otg_remove),
 897         .driver = {
 898                    .owner = THIS_MODULE,
 899                    .name = driver_name,
 900                    },
 901 #ifdef CONFIG_PM
 902         .suspend = mv_otg_suspend,
 903         .resume = mv_otg_resume,
 904 #endif
 905 };
 906 module_platform_driver(mv_otg_driver);