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

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