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/io.h>
  15 #include <linux/uaccess.h>
  16 #include <linux/device.h>
  17 #include <linux/proc_fs.h>
  18 #include <linux/clk.h>
  19 #include <linux/workqueue.h>
  20 #include <linux/platform_device.h>
  21
  22 #include <linux/usb.h>
  23 #include <linux/usb/ch9.h>
  24 #include <linux/usb/otg.h>
  25 #include <linux/usb/gadget.h>
  26 #include <linux/usb/hcd.h>
  27 #include <linux/platform_data/mv_usb.h>
  28
  29 #include "phy-mv-usb.h"
  30
  31 #define DRIVER_DESC     "Marvell USB OTG transceiver driver"
  32
  33 MODULE_DESCRIPTION(DRIVER_DESC);
  34 MODULE_LICENSE("GPL");
  35
  36 static const char driver_name[] = "mv-otg";
  37
  38 static char *state_string[] = {
  39         "undefined",
  40         "b_idle",
  41         "b_srp_init",
  42         "b_peripheral",
  43         "b_wait_acon",
  44         "b_host",
  45         "a_idle",
  46         "a_wait_vrise",
  47         "a_wait_bcon",
  48         "a_host",
  49         "a_suspend",
  50         "a_peripheral",
  51         "a_wait_vfall",
  52         "a_vbus_err"
  53 };
  54
  55 static int mv_otg_set_vbus(struct usb_otg *otg, bool on)
  56 {
  57         struct mv_otg *mvotg = container_of(otg->usb_phy, struct mv_otg, phy);
  58         if (mvotg->pdata->set_vbus == NULL)
  59                 return -ENODEV;
  60
  61         return mvotg->pdata->set_vbus(on);
  62 }
  63
  64 static int mv_otg_set_host(struct usb_otg *otg,
  65                            struct usb_bus *host)
  66 {
  67         otg->host = host;
  68
  69         return 0;
  70 }
  71
  72 static int mv_otg_set_peripheral(struct usb_otg *otg,
  73                                  struct usb_gadget *gadget)
  74 {
  75         otg->gadget = gadget;
  76
  77         return 0;
  78 }
  79
  80 static void mv_otg_run_state_machine(struct mv_otg *mvotg,
  81                                      unsigned long delay)
  82 {
  83         dev_dbg(&mvotg->pdev->dev, "transceiver is updated\n");
  84         if (!mvotg->qwork)
  85                 return;
  86
  87         queue_delayed_work(mvotg->qwork, &mvotg->work, delay);
  88 }
  89
  90 static void mv_otg_timer_await_bcon(unsigned long data)
  91 {
  92         struct mv_otg *mvotg = (struct mv_otg *) data;
  93
  94         mvotg->otg_ctrl.a_wait_bcon_timeout = 1;
  95
  96         dev_info(&mvotg->pdev->dev, "B Device No Response!\n");
  97
  98         if (spin_trylock(&mvotg->wq_lock)) {
  99                 mv_otg_run_state_machine(mvotg, 0);
 100                 spin_unlock(&mvotg->wq_lock);
 101         }
 102 }
 103
 104 static int mv_otg_cancel_timer(struct mv_otg *mvotg, unsigned int id)
 105 {
 106         struct timer_list *timer;
 107
 108         if (id >= OTG_TIMER_NUM)
 109                 return -EINVAL;
 110
 111         timer = &mvotg->otg_ctrl.timer[id];
 112
 113         if (timer_pending(timer))
 114                 del_timer(timer);
 115
 116         return 0;
 117 }
 118
 119 static int mv_otg_set_timer(struct mv_otg *mvotg, unsigned int id,
 120                             unsigned long interval,
 121                             void (*callback) (unsigned long))
 122 {
 123         struct timer_list *timer;
 124
 125         if (id >= OTG_TIMER_NUM)
 126                 return -EINVAL;
 127
 128         timer = &mvotg->otg_ctrl.timer[id];
 129         if (timer_pending(timer)) {
 130                 dev_err(&mvotg->pdev->dev, "Timer%d is already running\n", id);
 131                 return -EBUSY;
 132         }
 133
 134         init_timer(timer);
 135         timer->data = (unsigned long) mvotg;
 136         timer->function = callback;
 137         timer->expires = jiffies + interval;
 138         add_timer(timer);
 139
 140         return 0;
 141 }
 142
 143 static int mv_otg_reset(struct mv_otg *mvotg)
 144 {
 145         unsigned int loops;
 146         u32 tmp;
 147
 148         /* Stop the controller */
 149         tmp = readl(&mvotg->op_regs->usbcmd);
 150         tmp &= ~USBCMD_RUN_STOP;
 151         writel(tmp, &mvotg->op_regs->usbcmd);
 152
 153         /* Reset the controller to get default values */
 154         writel(USBCMD_CTRL_RESET, &mvotg->op_regs->usbcmd);
 155
 156         loops = 500;
 157         while (readl(&mvotg->op_regs->usbcmd) & USBCMD_CTRL_RESET) {
 158                 if (loops == 0) {
 159                         dev_err(&mvotg->pdev->dev,
 160                                 "Wait for RESET completed TIMEOUT\n");
 161                         return -ETIMEDOUT;
 162                 }
 163                 loops--;
 164                 udelay(20);
 165         }
 166
 167         writel(0x0, &mvotg->op_regs->usbintr);
 168         tmp = readl(&mvotg->op_regs->usbsts);
 169         writel(tmp, &mvotg->op_regs->usbsts);
 170
 171         return 0;
 172 }
 173
 174 static void mv_otg_init_irq(struct mv_otg *mvotg)
 175 {
 176         u32 otgsc;
 177
 178         mvotg->irq_en = OTGSC_INTR_A_SESSION_VALID
 179             | OTGSC_INTR_A_VBUS_VALID;
 180         mvotg->irq_status = OTGSC_INTSTS_A_SESSION_VALID
 181             | OTGSC_INTSTS_A_VBUS_VALID;
 182
 183         if (mvotg->pdata->vbus == NULL) {
 184                 mvotg->irq_en |= OTGSC_INTR_B_SESSION_VALID
 185                     | OTGSC_INTR_B_SESSION_END;
 186                 mvotg->irq_status |= OTGSC_INTSTS_B_SESSION_VALID
 187                     | OTGSC_INTSTS_B_SESSION_END;
 188         }
 189
 190         if (mvotg->pdata->id == NULL) {
 191                 mvotg->irq_en |= OTGSC_INTR_USB_ID;
 192                 mvotg->irq_status |= OTGSC_INTSTS_USB_ID;
 193         }
 194
 195         otgsc = readl(&mvotg->op_regs->otgsc);
 196         otgsc |= mvotg->irq_en;
 197         writel(otgsc, &mvotg->op_regs->otgsc);
 198 }
 199
 200 static void mv_otg_start_host(struct mv_otg *mvotg, int on)
 201 {
 202 #ifdef CONFIG_USB
 203         struct usb_otg *otg = mvotg->phy.otg;
 204         struct usb_hcd *hcd;
 205
 206         if (!otg->host)
 207                 return;
 208
 209         dev_info(&mvotg->pdev->dev, "%s host\n", on ? "start" : "stop");
 210
 211         hcd = bus_to_hcd(otg->host);
 212
 213         if (on) {
 214                 usb_add_hcd(hcd, hcd->irq, IRQF_SHARED);
 215                 device_wakeup_enable(hcd->self.controller);
 216         } else {
 217                 usb_remove_hcd(hcd);
 218         }
 219 #endif /* CONFIG_USB */
 220 }
 221
 222 static void mv_otg_start_periphrals(struct mv_otg *mvotg, int on)
 223 {
 224         struct usb_otg *otg = mvotg->phy.otg;
 225
 226         if (!otg->gadget)
 227                 return;
 228
 229         dev_info(mvotg->phy.dev, "gadget %s\n", on ? "on" : "off");
 230
 231         if (on)
 232                 usb_gadget_vbus_connect(otg->gadget);
 233         else
 234                 usb_gadget_vbus_disconnect(otg->gadget);
 235 }
 236
 237 static void otg_clock_enable(struct mv_otg *mvotg)
 238 {
 239         clk_prepare_enable(mvotg->clk);
 240 }
 241
 242 static void otg_clock_disable(struct mv_otg *mvotg)
 243 {
 244         clk_disable_unprepare(mvotg->clk);
 245 }
 246
 247 static int mv_otg_enable_internal(struct mv_otg *mvotg)
 248 {
 249         int retval = 0;
 250
 251         if (mvotg->active)
 252                 return 0;
 253
 254         dev_dbg(&mvotg->pdev->dev, "otg enabled\n");
 255
 256         otg_clock_enable(mvotg);
 257         if (mvotg->pdata->phy_init) {
 258                 retval = mvotg->pdata->phy_init(mvotg->phy_regs);
 259                 if (retval) {
 260                         dev_err(&mvotg->pdev->dev,
 261                                 "init phy error %d\n", retval);
 262                         otg_clock_disable(mvotg);
 263                         return retval;
 264                 }
 265         }
 266         mvotg->active = 1;
 267
 268         return 0;
 269
 270 }
 271
 272 static int mv_otg_enable(struct mv_otg *mvotg)
 273 {
 274         if (mvotg->clock_gating)
 275                 return mv_otg_enable_internal(mvotg);
 276
 277         return 0;
 278 }
 279
 280 static void mv_otg_disable_internal(struct mv_otg *mvotg)
 281 {
 282         if (mvotg->active) {
 283                 dev_dbg(&mvotg->pdev->dev, "otg disabled\n");
 284                 if (mvotg->pdata->phy_deinit)
 285                         mvotg->pdata->phy_deinit(mvotg->phy_regs);
 286                 otg_clock_disable(mvotg);
 287                 mvotg->active = 0;
 288         }
 289 }
 290
 291 static void mv_otg_disable(struct mv_otg *mvotg)
 292 {
 293         if (mvotg->clock_gating)
 294                 mv_otg_disable_internal(mvotg);
 295 }
 296
 297 static void mv_otg_update_inputs(struct mv_otg *mvotg)
 298 {
 299         struct mv_otg_ctrl *otg_ctrl = &mvotg->otg_ctrl;
 300         u32 otgsc;
 301
 302         otgsc = readl(&mvotg->op_regs->otgsc);
 303
 304         if (mvotg->pdata->vbus) {
 305                 if (mvotg->pdata->vbus->poll() == VBUS_HIGH) {
 306                         otg_ctrl->b_sess_vld = 1;
 307                         otg_ctrl->b_sess_end = 0;
 308                 } else {
 309                         otg_ctrl->b_sess_vld = 0;
 310                         otg_ctrl->b_sess_end = 1;
 311                 }
 312         } else {
 313                 otg_ctrl->b_sess_vld = !!(otgsc & OTGSC_STS_B_SESSION_VALID);
 314                 otg_ctrl->b_sess_end = !!(otgsc & OTGSC_STS_B_SESSION_END);
 315         }
 316
 317         if (mvotg->pdata->id)
 318                 otg_ctrl->id = !!mvotg->pdata->id->poll();
 319         else
 320                 otg_ctrl->id = !!(otgsc & OTGSC_STS_USB_ID);
 321
 322         if (mvotg->pdata->otg_force_a_bus_req && !otg_ctrl->id)
 323                 otg_ctrl->a_bus_req = 1;
 324
 325         otg_ctrl->a_sess_vld = !!(otgsc & OTGSC_STS_A_SESSION_VALID);
 326         otg_ctrl->a_vbus_vld = !!(otgsc & OTGSC_STS_A_VBUS_VALID);
 327
 328         dev_dbg(&mvotg->pdev->dev, "%s: ", __func__);
 329         dev_dbg(&mvotg->pdev->dev, "id %d\n", otg_ctrl->id);
 330         dev_dbg(&mvotg->pdev->dev, "b_sess_vld %d\n", otg_ctrl->b_sess_vld);
 331         dev_dbg(&mvotg->pdev->dev, "b_sess_end %d\n", otg_ctrl->b_sess_end);
 332         dev_dbg(&mvotg->pdev->dev, "a_vbus_vld %d\n", otg_ctrl->a_vbus_vld);
 333         dev_dbg(&mvotg->pdev->dev, "a_sess_vld %d\n", otg_ctrl->a_sess_vld);
 334 }
 335
 336 static void mv_otg_update_state(struct mv_otg *mvotg)
 337 {
 338         struct mv_otg_ctrl *otg_ctrl = &mvotg->otg_ctrl;
 339         int old_state = mvotg->phy.otg->state;
 340
 341         switch (old_state) {
 342         case OTG_STATE_UNDEFINED:
 343                 mvotg->phy.otg->state = OTG_STATE_B_IDLE;
 344                 /* FALL THROUGH */
 345         case OTG_STATE_B_IDLE:
 346                 if (otg_ctrl->id == 0)
 347                         mvotg->phy.otg->state = OTG_STATE_A_IDLE;
 348                 else if (otg_ctrl->b_sess_vld)
 349                         mvotg->phy.otg->state = OTG_STATE_B_PERIPHERAL;
 350                 break;
 351         case OTG_STATE_B_PERIPHERAL:
 352                 if (!otg_ctrl->b_sess_vld || otg_ctrl->id == 0)
 353                         mvotg->phy.otg->state = OTG_STATE_B_IDLE;
 354                 break;
 355         case OTG_STATE_A_IDLE:
 356                 if (otg_ctrl->id)
 357                         mvotg->phy.otg->state = OTG_STATE_B_IDLE;
 358                 else if (!(otg_ctrl->a_bus_drop) &&
 359                          (otg_ctrl->a_bus_req || otg_ctrl->a_srp_det))
 360                         mvotg->phy.otg->state = OTG_STATE_A_WAIT_VRISE;
 361                 break;
 362         case OTG_STATE_A_WAIT_VRISE:
 363                 if (otg_ctrl->a_vbus_vld)
 364                         mvotg->phy.otg->state = OTG_STATE_A_WAIT_BCON;
 365                 break;
 366         case OTG_STATE_A_WAIT_BCON:
 367                 if (otg_ctrl->id || otg_ctrl->a_bus_drop
 368                     || otg_ctrl->a_wait_bcon_timeout) {
 369                         mv_otg_cancel_timer(mvotg, A_WAIT_BCON_TIMER);
 370                         mvotg->otg_ctrl.a_wait_bcon_timeout = 0;
 371                         mvotg->phy.otg->state = OTG_STATE_A_WAIT_VFALL;
 372                         otg_ctrl->a_bus_req = 0;
 373                 } else if (!otg_ctrl->a_vbus_vld) {
 374                         mv_otg_cancel_timer(mvotg, A_WAIT_BCON_TIMER);
 375                         mvotg->otg_ctrl.a_wait_bcon_timeout = 0;
 376                         mvotg->phy.otg->state = OTG_STATE_A_VBUS_ERR;
 377                 } else if (otg_ctrl->b_conn) {
 378                         mv_otg_cancel_timer(mvotg, A_WAIT_BCON_TIMER);
 379                         mvotg->otg_ctrl.a_wait_bcon_timeout = 0;
 380                         mvotg->phy.otg->state = OTG_STATE_A_HOST;
 381                 }
 382                 break;
 383         case OTG_STATE_A_HOST:
 384                 if (otg_ctrl->id || !otg_ctrl->b_conn
 385                     || otg_ctrl->a_bus_drop)
 386                         mvotg->phy.otg->state = OTG_STATE_A_WAIT_BCON;
 387                 else if (!otg_ctrl->a_vbus_vld)
 388                         mvotg->phy.otg->state = OTG_STATE_A_VBUS_ERR;
 389                 break;
 390         case OTG_STATE_A_WAIT_VFALL:
 391                 if (otg_ctrl->id
 392                     || (!otg_ctrl->b_conn && otg_ctrl->a_sess_vld)
 393                     || otg_ctrl->a_bus_req)
 394                         mvotg->phy.otg->state = OTG_STATE_A_IDLE;
 395                 break;
 396         case OTG_STATE_A_VBUS_ERR:
 397                 if (otg_ctrl->id || otg_ctrl->a_clr_err
 398                     || otg_ctrl->a_bus_drop) {
 399                         otg_ctrl->a_clr_err = 0;
 400                         mvotg->phy.otg->state = OTG_STATE_A_WAIT_VFALL;
 401                 }
 402                 break;
 403         default:
 404                 break;
 405         }
 406 }
 407
 408 static void mv_otg_work(struct work_struct *work)
 409 {
 410         struct mv_otg *mvotg;
 411         struct usb_phy *phy;
 412         struct usb_otg *otg;
 413         int old_state;
 414
 415         mvotg = container_of(to_delayed_work(work), struct mv_otg, work);
 416
 417 run:
 418         /* work queue is single thread, or we need spin_lock to protect */
 419         phy = &mvotg->phy;
 420         otg = mvotg->phy.otg;
 421         old_state = otg->state;
 422
 423         if (!mvotg->active)
 424                 return;
 425
 426         mv_otg_update_inputs(mvotg);
 427         mv_otg_update_state(mvotg);
 428
 429         if (old_state != mvotg->phy.otg->state) {
 430                 dev_info(&mvotg->pdev->dev, "change from state %s to %s\n",
 431                          state_string[old_state],
 432                          state_string[mvotg->phy.otg->state]);
 433
 434                 switch (mvotg->phy.otg->state) {
 435                 case OTG_STATE_B_IDLE:
 436                         otg->default_a = 0;
 437                         if (old_state == OTG_STATE_B_PERIPHERAL)
 438                                 mv_otg_start_periphrals(mvotg, 0);
 439                         mv_otg_reset(mvotg);
 440                         mv_otg_disable(mvotg);
 441                         usb_phy_set_event(&mvotg->phy, USB_EVENT_NONE);
 442                         break;
 443                 case OTG_STATE_B_PERIPHERAL:
 444                         mv_otg_enable(mvotg);
 445                         mv_otg_start_periphrals(mvotg, 1);
 446                         usb_phy_set_event(&mvotg->phy, USB_EVENT_ENUMERATED);
 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.otg->state != OTG_STATE_B_IDLE
 548             && mvotg->phy.otg->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 const struct attribute_group inputs_attr_group = {
 652         .name = "inputs",
 653         .attrs = inputs_attrs,
 654 };
 655
 656 static 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 = dev_get_platdata(&pdev->dev);
 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                 return -ENOMEM;
 690
 691         otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);
 692         if (!otg)
 693                 return -ENOMEM;
 694
 695         platform_set_drvdata(pdev, mvotg);
 696
 697         mvotg->pdev = pdev;
 698         mvotg->pdata = pdata;
 699
 700         mvotg->clk = devm_clk_get(&pdev->dev, NULL);
 701         if (IS_ERR(mvotg->clk))
 702                 return PTR_ERR(mvotg->clk);
 703
 704         mvotg->qwork = create_singlethread_workqueue("mv_otg_queue");
 705         if (!mvotg->qwork) {
 706                 dev_dbg(&pdev->dev, "cannot create workqueue for OTG\n");
 707                 return -ENOMEM;
 708         }
 709
 710         INIT_DELAYED_WORK(&mvotg->work, mv_otg_work);
 711
 712         /* OTG common part */
 713         mvotg->pdev = pdev;
 714         mvotg->phy.dev = &pdev->dev;
 715         mvotg->phy.otg = otg;
 716         mvotg->phy.label = driver_name;
 717
 718         otg->state = OTG_STATE_UNDEFINED;
 719         otg->usb_phy = &mvotg->phy;
 720         otg->set_host = mv_otg_set_host;
 721         otg->set_peripheral = mv_otg_set_peripheral;
 722         otg->set_vbus = mv_otg_set_vbus;
 723
 724         for (i = 0; i < OTG_TIMER_NUM; i++)
 725                 init_timer(&mvotg->otg_ctrl.timer[i]);
 726
 727         r = platform_get_resource_byname(mvotg->pdev,
 728                                          IORESOURCE_MEM, "phyregs");
 729         if (r == NULL) {
 730                 dev_err(&pdev->dev, "no phy I/O memory resource defined\n");
 731                 retval = -ENODEV;
 732                 goto err_destroy_workqueue;
 733         }
 734
 735         mvotg->phy_regs = devm_ioremap(&pdev->dev, r->start, resource_size(r));
 736         if (mvotg->phy_regs == NULL) {
 737                 dev_err(&pdev->dev, "failed to map phy I/O memory\n");
 738                 retval = -EFAULT;
 739                 goto err_destroy_workqueue;
 740         }
 741
 742         r = platform_get_resource_byname(mvotg->pdev,
 743                                          IORESOURCE_MEM, "capregs");
 744         if (r == NULL) {
 745                 dev_err(&pdev->dev, "no I/O memory resource defined\n");
 746                 retval = -ENODEV;
 747                 goto err_destroy_workqueue;
 748         }
 749
 750         mvotg->cap_regs = devm_ioremap(&pdev->dev, r->start, resource_size(r));
 751         if (mvotg->cap_regs == NULL) {
 752                 dev_err(&pdev->dev, "failed to map I/O memory\n");
 753                 retval = -EFAULT;
 754                 goto err_destroy_workqueue;
 755         }
 756
 757         /* we will acces controller register, so enable the udc controller */
 758         retval = mv_otg_enable_internal(mvotg);
 759         if (retval) {
 760                 dev_err(&pdev->dev, "mv otg enable error %d\n", retval);
 761                 goto err_destroy_workqueue;
 762         }
 763
 764         mvotg->op_regs =
 765                 (struct mv_otg_regs __iomem *) ((unsigned long) mvotg->cap_regs
 766                         + (readl(mvotg->cap_regs) & CAPLENGTH_MASK));
 767
 768         if (pdata->id) {
 769                 retval = devm_request_threaded_irq(&pdev->dev, pdata->id->irq,
 770                                                 NULL, mv_otg_inputs_irq,
 771                                                 IRQF_ONESHOT, "id", mvotg);
 772                 if (retval) {
 773                         dev_info(&pdev->dev,
 774                                  "Failed to request irq for ID\n");
 775                         pdata->id = NULL;
 776                 }
 777         }
 778
 779         if (pdata->vbus) {
 780                 mvotg->clock_gating = 1;
 781                 retval = devm_request_threaded_irq(&pdev->dev, pdata->vbus->irq,
 782                                                 NULL, mv_otg_inputs_irq,
 783                                                 IRQF_ONESHOT, "vbus", mvotg);
 784                 if (retval) {
 785                         dev_info(&pdev->dev,
 786                                  "Failed to request irq for VBUS, "
 787                                  "disable clock gating\n");
 788                         mvotg->clock_gating = 0;
 789                         pdata->vbus = NULL;
 790                 }
 791         }
 792
 793         if (pdata->disable_otg_clock_gating)
 794                 mvotg->clock_gating = 0;
 795
 796         mv_otg_reset(mvotg);
 797         mv_otg_init_irq(mvotg);
 798
 799         r = platform_get_resource(mvotg->pdev, IORESOURCE_IRQ, 0);
 800         if (r == NULL) {
 801                 dev_err(&pdev->dev, "no IRQ resource defined\n");
 802                 retval = -ENODEV;
 803                 goto err_disable_clk;
 804         }
 805
 806         mvotg->irq = r->start;
 807         if (devm_request_irq(&pdev->dev, mvotg->irq, mv_otg_irq, IRQF_SHARED,
 808                         driver_name, mvotg)) {
 809                 dev_err(&pdev->dev, "Request irq %d for OTG failed\n",
 810                         mvotg->irq);
 811                 mvotg->irq = 0;
 812                 retval = -ENODEV;
 813                 goto err_disable_clk;
 814         }
 815
 816         retval = usb_add_phy(&mvotg->phy, USB_PHY_TYPE_USB2);
 817         if (retval < 0) {
 818                 dev_err(&pdev->dev, "can't register transceiver, %d\n",
 819                         retval);
 820                 goto err_disable_clk;
 821         }
 822
 823         retval = sysfs_create_group(&pdev->dev.kobj, &inputs_attr_group);
 824         if (retval < 0) {
 825                 dev_dbg(&pdev->dev,
 826                         "Can't register sysfs attr group: %d\n", retval);
 827                 goto err_remove_phy;
 828         }
 829
 830         spin_lock_init(&mvotg->wq_lock);
 831         if (spin_trylock(&mvotg->wq_lock)) {
 832                 mv_otg_run_state_machine(mvotg, 2 * HZ);
 833                 spin_unlock(&mvotg->wq_lock);
 834         }
 835
 836         dev_info(&pdev->dev,
 837                  "successful probe OTG device %s clock gating.\n",
 838                  mvotg->clock_gating ? "with" : "without");
 839
 840         return 0;
 841
 842 err_remove_phy:
 843         usb_remove_phy(&mvotg->phy);
 844 err_disable_clk:
 845         mv_otg_disable_internal(mvotg);
 846 err_destroy_workqueue:
 847         flush_workqueue(mvotg->qwork);
 848         destroy_workqueue(mvotg->qwork);
 849
 850         return retval;
 851 }
 852
 853 #ifdef CONFIG_PM
 854 static int mv_otg_suspend(struct platform_device *pdev, pm_message_t state)
 855 {
 856         struct mv_otg *mvotg = platform_get_drvdata(pdev);
 857
 858         if (mvotg->phy.otg->state != OTG_STATE_B_IDLE) {
 859                 dev_info(&pdev->dev,
 860                          "OTG state is not B_IDLE, it is %d!\n",
 861                          mvotg->phy.otg->state);
 862                 return -EAGAIN;
 863         }
 864
 865         if (!mvotg->clock_gating)
 866                 mv_otg_disable_internal(mvotg);
 867
 868         return 0;
 869 }
 870
 871 static int mv_otg_resume(struct platform_device *pdev)
 872 {
 873         struct mv_otg *mvotg = platform_get_drvdata(pdev);
 874         u32 otgsc;
 875
 876         if (!mvotg->clock_gating) {
 877                 mv_otg_enable_internal(mvotg);
 878
 879                 otgsc = readl(&mvotg->op_regs->otgsc);
 880                 otgsc |= mvotg->irq_en;
 881                 writel(otgsc, &mvotg->op_regs->otgsc);
 882
 883                 if (spin_trylock(&mvotg->wq_lock)) {
 884                         mv_otg_run_state_machine(mvotg, 0);
 885                         spin_unlock(&mvotg->wq_lock);
 886                 }
 887         }
 888         return 0;
 889 }
 890 #endif
 891
 892 static struct platform_driver mv_otg_driver = {
 893         .probe = mv_otg_probe,
 894         .remove = mv_otg_remove,
 895         .driver = {
 896                    .name = driver_name,
 897                    },
 898 #ifdef CONFIG_PM
 899         .suspend = mv_otg_suspend,
 900         .resume = mv_otg_resume,
 901 #endif
 902 };
 903 module_platform_driver(mv_otg_driver);