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 #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->usb_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         int old_state = mvotg->phy.otg->state;
 342
 343         switch (old_state) {
 344         case OTG_STATE_UNDEFINED:
 345                 mvotg->phy.otg->state = OTG_STATE_B_IDLE;
 346                 /* FALL THROUGH */
 347         case OTG_STATE_B_IDLE:
 348                 if (otg_ctrl->id == 0)
 349                         mvotg->phy.otg->state = OTG_STATE_A_IDLE;
 350                 else if (otg_ctrl->b_sess_vld)
 351                         mvotg->phy.otg->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                         mvotg->phy.otg->state = OTG_STATE_B_IDLE;
 356                 break;
 357         case OTG_STATE_A_IDLE:
 358                 if (otg_ctrl->id)
 359                         mvotg->phy.otg->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                         mvotg->phy.otg->state = OTG_STATE_A_WAIT_VRISE;
 363                 break;
 364         case OTG_STATE_A_WAIT_VRISE:
 365                 if (otg_ctrl->a_vbus_vld)
 366                         mvotg->phy.otg->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                         mvotg->phy.otg->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                         mvotg->phy.otg->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                         mvotg->phy.otg->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                         mvotg->phy.otg->state = OTG_STATE_A_WAIT_BCON;
 389                 else if (!otg_ctrl->a_vbus_vld)
 390                         mvotg->phy.otg->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                         mvotg->phy.otg->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                         mvotg->phy.otg->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 = mvotg->phy.otg;
 423         old_state = otg->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 != mvotg->phy.otg->state) {
 432                 dev_info(&mvotg->pdev->dev, "change from state %s to %s\n",
 433                          state_string[old_state],
 434                          state_string[mvotg->phy.otg->state]);
 435
 436                 switch (mvotg->phy.otg->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                         usb_phy_set_event(&mvotg->phy, USB_EVENT_NONE);
 444                         break;
 445                 case OTG_STATE_B_PERIPHERAL:
 446                         mv_otg_enable(mvotg);
 447                         mv_otg_start_periphrals(mvotg, 1);
 448                         usb_phy_set_event(&mvotg->phy, USB_EVENT_ENUMERATED);
 449                         break;
 450                 case OTG_STATE_A_IDLE:
 451                         otg->default_a = 1;
 452                         mv_otg_enable(mvotg);
 453                         if (old_state == OTG_STATE_A_WAIT_VFALL)
 454                                 mv_otg_start_host(mvotg, 0);
 455                         mv_otg_reset(mvotg);
 456                         break;
 457                 case OTG_STATE_A_WAIT_VRISE:
 458                         mv_otg_set_vbus(otg, 1);
 459                         break;
 460                 case OTG_STATE_A_WAIT_BCON:
 461                         if (old_state != OTG_STATE_A_HOST)
 462                                 mv_otg_start_host(mvotg, 1);
 463                         mv_otg_set_timer(mvotg, A_WAIT_BCON_TIMER,
 464                                          T_A_WAIT_BCON,
 465                                          mv_otg_timer_await_bcon);
 466                         /*
 467                          * Now, we directly enter A_HOST. So set b_conn = 1
 468                          * here. In fact, it need host driver to notify us.
 469                          */
 470                         mvotg->otg_ctrl.b_conn = 1;
 471                         break;
 472                 case OTG_STATE_A_HOST:
 473                         break;
 474                 case OTG_STATE_A_WAIT_VFALL:
 475                         /*
 476                          * Now, we has exited A_HOST. So set b_conn = 0
 477                          * here. In fact, it need host driver to notify us.
 478                          */
 479                         mvotg->otg_ctrl.b_conn = 0;
 480                         mv_otg_set_vbus(otg, 0);
 481                         break;
 482                 case OTG_STATE_A_VBUS_ERR:
 483                         break;
 484                 default:
 485                         break;
 486                 }
 487                 goto run;
 488         }
 489 }
 490
 491 static irqreturn_t mv_otg_irq(int irq, void *dev)
 492 {
 493         struct mv_otg *mvotg = dev;
 494         u32 otgsc;
 495
 496         otgsc = readl(&mvotg->op_regs->otgsc);
 497         writel(otgsc, &mvotg->op_regs->otgsc);
 498
 499         /*
 500          * if we have vbus, then the vbus detection for B-device
 501          * will be done by mv_otg_inputs_irq().
 502          */
 503         if (mvotg->pdata->vbus)
 504                 if ((otgsc & OTGSC_STS_USB_ID) &&
 505                     !(otgsc & OTGSC_INTSTS_USB_ID))
 506                         return IRQ_NONE;
 507
 508         if ((otgsc & mvotg->irq_status) == 0)
 509                 return IRQ_NONE;
 510
 511         mv_otg_run_state_machine(mvotg, 0);
 512
 513         return IRQ_HANDLED;
 514 }
 515
 516 static irqreturn_t mv_otg_inputs_irq(int irq, void *dev)
 517 {
 518         struct mv_otg *mvotg = dev;
 519
 520         /* The clock may disabled at this time */
 521         if (!mvotg->active) {
 522                 mv_otg_enable(mvotg);
 523                 mv_otg_init_irq(mvotg);
 524         }
 525
 526         mv_otg_run_state_machine(mvotg, 0);
 527
 528         return IRQ_HANDLED;
 529 }
 530
 531 static ssize_t
 532 get_a_bus_req(struct device *dev, struct device_attribute *attr, char *buf)
 533 {
 534         struct mv_otg *mvotg = dev_get_drvdata(dev);
 535         return scnprintf(buf, PAGE_SIZE, "%d\n",
 536                          mvotg->otg_ctrl.a_bus_req);
 537 }
 538
 539 static ssize_t
 540 set_a_bus_req(struct device *dev, struct device_attribute *attr,
 541               const char *buf, size_t count)
 542 {
 543         struct mv_otg *mvotg = dev_get_drvdata(dev);
 544
 545         if (count > 2)
 546                 return -1;
 547
 548         /* We will use this interface to change to A device */
 549         if (mvotg->phy.otg->state != OTG_STATE_B_IDLE
 550             && mvotg->phy.otg->state != OTG_STATE_A_IDLE)
 551                 return -1;
 552
 553         /* The clock may disabled and we need to set irq for ID detected */
 554         mv_otg_enable(mvotg);
 555         mv_otg_init_irq(mvotg);
 556
 557         if (buf[0] == '1') {
 558                 mvotg->otg_ctrl.a_bus_req = 1;
 559                 mvotg->otg_ctrl.a_bus_drop = 0;
 560                 dev_dbg(&mvotg->pdev->dev,
 561                         "User request: a_bus_req = 1\n");
 562
 563                 if (spin_trylock(&mvotg->wq_lock)) {
 564                         mv_otg_run_state_machine(mvotg, 0);
 565                         spin_unlock(&mvotg->wq_lock);
 566                 }
 567         }
 568
 569         return count;
 570 }
 571
 572 static DEVICE_ATTR(a_bus_req, S_IRUGO | S_IWUSR, get_a_bus_req,
 573                    set_a_bus_req);
 574
 575 static ssize_t
 576 set_a_clr_err(struct device *dev, struct device_attribute *attr,
 577               const char *buf, size_t count)
 578 {
 579         struct mv_otg *mvotg = dev_get_drvdata(dev);
 580         if (!mvotg->phy.otg->default_a)
 581                 return -1;
 582
 583         if (count > 2)
 584                 return -1;
 585
 586         if (buf[0] == '1') {
 587                 mvotg->otg_ctrl.a_clr_err = 1;
 588                 dev_dbg(&mvotg->pdev->dev,
 589                         "User request: a_clr_err = 1\n");
 590         }
 591
 592         if (spin_trylock(&mvotg->wq_lock)) {
 593                 mv_otg_run_state_machine(mvotg, 0);
 594                 spin_unlock(&mvotg->wq_lock);
 595         }
 596
 597         return count;
 598 }
 599
 600 static DEVICE_ATTR(a_clr_err, S_IWUSR, NULL, set_a_clr_err);
 601
 602 static ssize_t
 603 get_a_bus_drop(struct device *dev, struct device_attribute *attr,
 604                char *buf)
 605 {
 606         struct mv_otg *mvotg = dev_get_drvdata(dev);
 607         return scnprintf(buf, PAGE_SIZE, "%d\n",
 608                          mvotg->otg_ctrl.a_bus_drop);
 609 }
 610
 611 static ssize_t
 612 set_a_bus_drop(struct device *dev, struct device_attribute *attr,
 613                const char *buf, size_t count)
 614 {
 615         struct mv_otg *mvotg = dev_get_drvdata(dev);
 616         if (!mvotg->phy.otg->default_a)
 617                 return -1;
 618
 619         if (count > 2)
 620                 return -1;
 621
 622         if (buf[0] == '0') {
 623                 mvotg->otg_ctrl.a_bus_drop = 0;
 624                 dev_dbg(&mvotg->pdev->dev,
 625                         "User request: a_bus_drop = 0\n");
 626         } else if (buf[0] == '1') {
 627                 mvotg->otg_ctrl.a_bus_drop = 1;
 628                 mvotg->otg_ctrl.a_bus_req = 0;
 629                 dev_dbg(&mvotg->pdev->dev,
 630                         "User request: a_bus_drop = 1\n");
 631                 dev_dbg(&mvotg->pdev->dev,
 632                         "User request: and a_bus_req = 0\n");
 633         }
 634
 635         if (spin_trylock(&mvotg->wq_lock)) {
 636                 mv_otg_run_state_machine(mvotg, 0);
 637                 spin_unlock(&mvotg->wq_lock);
 638         }
 639
 640         return count;
 641 }
 642
 643 static DEVICE_ATTR(a_bus_drop, S_IRUGO | S_IWUSR,
 644                    get_a_bus_drop, set_a_bus_drop);
 645
 646 static struct attribute *inputs_attrs[] = {
 647         &dev_attr_a_bus_req.attr,
 648         &dev_attr_a_clr_err.attr,
 649         &dev_attr_a_bus_drop.attr,
 650         NULL,
 651 };
 652
 653 static struct attribute_group inputs_attr_group = {
 654         .name = "inputs",
 655         .attrs = inputs_attrs,
 656 };
 657
 658 static int mv_otg_remove(struct platform_device *pdev)
 659 {
 660         struct mv_otg *mvotg = platform_get_drvdata(pdev);
 661
 662         sysfs_remove_group(&mvotg->pdev->dev.kobj, &inputs_attr_group);
 663
 664         if (mvotg->qwork) {
 665                 flush_workqueue(mvotg->qwork);
 666                 destroy_workqueue(mvotg->qwork);
 667         }
 668
 669         mv_otg_disable(mvotg);
 670
 671         usb_remove_phy(&mvotg->phy);
 672
 673         return 0;
 674 }
 675
 676 static int mv_otg_probe(struct platform_device *pdev)
 677 {
 678         struct mv_usb_platform_data *pdata = dev_get_platdata(&pdev->dev);
 679         struct mv_otg *mvotg;
 680         struct usb_otg *otg;
 681         struct resource *r;
 682         int retval = 0, i;
 683
 684         if (pdata == NULL) {
 685                 dev_err(&pdev->dev, "failed to get platform data\n");
 686                 return -ENODEV;
 687         }
 688
 689         mvotg = devm_kzalloc(&pdev->dev, sizeof(*mvotg), GFP_KERNEL);
 690         if (!mvotg)
 691                 return -ENOMEM;
 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
 720         otg->state = OTG_STATE_UNDEFINED;
 721         otg->usb_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.otg->state != OTG_STATE_B_IDLE) {
 861                 dev_info(&pdev->dev,
 862                          "OTG state is not B_IDLE, it is %d!\n",
 863                          mvotg->phy.otg->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 = mv_otg_remove,
 897         .driver = {
 898                    .name = driver_name,
 899                    },
 900 #ifdef CONFIG_PM
 901         .suspend = mv_otg_suspend,
 902         .resume = mv_otg_resume,
 903 #endif
 904 };
 905 module_platform_driver(mv_otg_driver);