kernel/drivers/usb/chipidea/udc.c

   1 /*
   2  * udc.c - ChipIdea UDC driver
   3  *
   4  * Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
   5  *
   6  * Author: David Lopo
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/delay.h>
  14 #include <linux/device.h>
  15 #include <linux/dmapool.h>
  16 #include <linux/err.h>
  17 #include <linux/irqreturn.h>
  18 #include <linux/kernel.h>
  19 #include <linux/slab.h>
  20 #include <linux/pm_runtime.h>
  21 #include <linux/usb/ch9.h>
  22 #include <linux/usb/gadget.h>
  23 #include <linux/usb/otg-fsm.h>
  24 #include <linux/usb/chipidea.h>
  25
  26 #include "ci.h"
  27 #include "udc.h"
  28 #include "bits.h"
  29 #include "debug.h"
  30 #include "otg.h"
  31 #include "otg_fsm.h"
  32
  33 /* control endpoint description */
  34 static const struct usb_endpoint_descriptor
  35 ctrl_endpt_out_desc = {
  36         .bLength         = USB_DT_ENDPOINT_SIZE,
  37         .bDescriptorType = USB_DT_ENDPOINT,
  38
  39         .bEndpointAddress = USB_DIR_OUT,
  40         .bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
  41         .wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
  42 };
  43
  44 static const struct usb_endpoint_descriptor
  45 ctrl_endpt_in_desc = {
  46         .bLength         = USB_DT_ENDPOINT_SIZE,
  47         .bDescriptorType = USB_DT_ENDPOINT,
  48
  49         .bEndpointAddress = USB_DIR_IN,
  50         .bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
  51         .wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
  52 };
  53
  54 /**
  55  * hw_ep_bit: calculates the bit number
  56  * @num: endpoint number
  57  * @dir: endpoint direction
  58  *
  59  * This function returns bit number
  60  */
  61 static inline int hw_ep_bit(int num, int dir)
  62 {
  63         return num + (dir ? 16 : 0);
  64 }
  65
  66 static inline int ep_to_bit(struct ci_hdrc *ci, int n)
  67 {
  68         int fill = 16 - ci->hw_ep_max / 2;
  69
  70         if (n >= ci->hw_ep_max / 2)
  71                 n += fill;
  72
  73         return n;
  74 }
  75
  76 /**
  77  * hw_device_state: enables/disables interrupts (execute without interruption)
  78  * @dma: 0 => disable, !0 => enable and set dma engine
  79  *
  80  * This function returns an error code
  81  */
  82 static int hw_device_state(struct ci_hdrc *ci, u32 dma)
  83 {
  84         if (dma) {
  85                 hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
  86                 /* interrupt, error, port change, reset, sleep/suspend */
  87                 hw_write(ci, OP_USBINTR, ~0,
  88                              USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
  89         } else {
  90                 hw_write(ci, OP_USBINTR, ~0, 0);
  91         }
  92         return 0;
  93 }
  94
  95 /**
  96  * hw_ep_flush: flush endpoint fifo (execute without interruption)
  97  * @num: endpoint number
  98  * @dir: endpoint direction
  99  *
 100  * This function returns an error code
 101  */
 102 static int hw_ep_flush(struct ci_hdrc *ci, int num, int dir)
 103 {
 104         int n = hw_ep_bit(num, dir);
 105
 106         do {
 107                 /* flush any pending transfer */
 108                 hw_write(ci, OP_ENDPTFLUSH, ~0, BIT(n));
 109                 while (hw_read(ci, OP_ENDPTFLUSH, BIT(n)))
 110                         cpu_relax();
 111         } while (hw_read(ci, OP_ENDPTSTAT, BIT(n)));
 112
 113         return 0;
 114 }
 115
 116 /**
 117  * hw_ep_disable: disables endpoint (execute without interruption)
 118  * @num: endpoint number
 119  * @dir: endpoint direction
 120  *
 121  * This function returns an error code
 122  */
 123 static int hw_ep_disable(struct ci_hdrc *ci, int num, int dir)
 124 {
 125         hw_ep_flush(ci, num, dir);
 126         hw_write(ci, OP_ENDPTCTRL + num,
 127                  dir ? ENDPTCTRL_TXE : ENDPTCTRL_RXE, 0);
 128         return 0;
 129 }
 130
 131 /**
 132  * hw_ep_enable: enables endpoint (execute without interruption)
 133  * @num:  endpoint number
 134  * @dir:  endpoint direction
 135  * @type: endpoint type
 136  *
 137  * This function returns an error code
 138  */
 139 static int hw_ep_enable(struct ci_hdrc *ci, int num, int dir, int type)
 140 {
 141         u32 mask, data;
 142
 143         if (dir) {
 144                 mask  = ENDPTCTRL_TXT;  /* type    */
 145                 data  = type << __ffs(mask);
 146
 147                 mask |= ENDPTCTRL_TXS;  /* unstall */
 148                 mask |= ENDPTCTRL_TXR;  /* reset data toggle */
 149                 data |= ENDPTCTRL_TXR;
 150                 mask |= ENDPTCTRL_TXE;  /* enable  */
 151                 data |= ENDPTCTRL_TXE;
 152         } else {
 153                 mask  = ENDPTCTRL_RXT;  /* type    */
 154                 data  = type << __ffs(mask);
 155
 156                 mask |= ENDPTCTRL_RXS;  /* unstall */
 157                 mask |= ENDPTCTRL_RXR;  /* reset data toggle */
 158                 data |= ENDPTCTRL_RXR;
 159                 mask |= ENDPTCTRL_RXE;  /* enable  */
 160                 data |= ENDPTCTRL_RXE;
 161         }
 162         hw_write(ci, OP_ENDPTCTRL + num, mask, data);
 163         return 0;
 164 }
 165
 166 /**
 167  * hw_ep_get_halt: return endpoint halt status
 168  * @num: endpoint number
 169  * @dir: endpoint direction
 170  *
 171  * This function returns 1 if endpoint halted
 172  */
 173 static int hw_ep_get_halt(struct ci_hdrc *ci, int num, int dir)
 174 {
 175         u32 mask = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
 176
 177         return hw_read(ci, OP_ENDPTCTRL + num, mask) ? 1 : 0;
 178 }
 179
 180 /**
 181  * hw_ep_prime: primes endpoint (execute without interruption)
 182  * @num:     endpoint number
 183  * @dir:     endpoint direction
 184  * @is_ctrl: true if control endpoint
 185  *
 186  * This function returns an error code
 187  */
 188 static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
 189 {
 190         int n = hw_ep_bit(num, dir);
 191
 192         if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
 193                 return -EAGAIN;
 194
 195         hw_write(ci, OP_ENDPTPRIME, ~0, BIT(n));
 196
 197         while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
 198                 cpu_relax();
 199         if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
 200                 return -EAGAIN;
 201
 202         /* status shoult be tested according with manual but it doesn't work */
 203         return 0;
 204 }
 205
 206 /**
 207  * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
 208  *                 without interruption)
 209  * @num:   endpoint number
 210  * @dir:   endpoint direction
 211  * @value: true => stall, false => unstall
 212  *
 213  * This function returns an error code
 214  */
 215 static int hw_ep_set_halt(struct ci_hdrc *ci, int num, int dir, int value)
 216 {
 217         if (value != 0 && value != 1)
 218                 return -EINVAL;
 219
 220         do {
 221                 enum ci_hw_regs reg = OP_ENDPTCTRL + num;
 222                 u32 mask_xs = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
 223                 u32 mask_xr = dir ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
 224
 225                 /* data toggle - reserved for EP0 but it's in ESS */
 226                 hw_write(ci, reg, mask_xs|mask_xr,
 227                           value ? mask_xs : mask_xr);
 228         } while (value != hw_ep_get_halt(ci, num, dir));
 229
 230         return 0;
 231 }
 232
 233 /**
 234  * hw_is_port_high_speed: test if port is high speed
 235  *
 236  * This function returns true if high speed port
 237  */
 238 static int hw_port_is_high_speed(struct ci_hdrc *ci)
 239 {
 240         return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
 241                 hw_read(ci, OP_PORTSC, PORTSC_HSP);
 242 }
 243
 244 /**
 245  * hw_test_and_clear_complete: test & clear complete status (execute without
 246  *                             interruption)
 247  * @n: endpoint number
 248  *
 249  * This function returns complete status
 250  */
 251 static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
 252 {
 253         n = ep_to_bit(ci, n);
 254         return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
 255 }
 256
 257 /**
 258  * hw_test_and_clear_intr_active: test & clear active interrupts (execute
 259  *                                without interruption)
 260  *
 261  * This function returns active interrutps
 262  */
 263 static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
 264 {
 265         u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
 266
 267         hw_write(ci, OP_USBSTS, ~0, reg);
 268         return reg;
 269 }
 270
 271 /**
 272  * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
 273  *                                interruption)
 274  *
 275  * This function returns guard value
 276  */
 277 static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
 278 {
 279         return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
 280 }
 281
 282 /**
 283  * hw_test_and_set_setup_guard: test & set setup guard (execute without
 284  *                              interruption)
 285  *
 286  * This function returns guard value
 287  */
 288 static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
 289 {
 290         return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
 291 }
 292
 293 /**
 294  * hw_usb_set_address: configures USB address (execute without interruption)
 295  * @value: new USB address
 296  *
 297  * This function explicitly sets the address, without the "USBADRA" (advance)
 298  * feature, which is not supported by older versions of the controller.
 299  */
 300 static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
 301 {
 302         hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
 303                  value << __ffs(DEVICEADDR_USBADR));
 304 }
 305
 306 /**
 307  * hw_usb_reset: restart device after a bus reset (execute without
 308  *               interruption)
 309  *
 310  * This function returns an error code
 311  */
 312 static int hw_usb_reset(struct ci_hdrc *ci)
 313 {
 314         hw_usb_set_address(ci, 0);
 315
 316         /* ESS flushes only at end?!? */
 317         hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
 318
 319         /* clear setup token semaphores */
 320         hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
 321
 322         /* clear complete status */
 323         hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
 324
 325         /* wait until all bits cleared */
 326         while (hw_read(ci, OP_ENDPTPRIME, ~0))
 327                 udelay(10);             /* not RTOS friendly */
 328
 329         /* reset all endpoints ? */
 330
 331         /* reset internal status and wait for further instructions
 332            no need to verify the port reset status (ESS does it) */
 333
 334         return 0;
 335 }
 336
 337 /******************************************************************************
 338  * UTIL block
 339  *****************************************************************************/
 340
 341 static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
 342                           unsigned length)
 343 {
 344         int i;
 345         u32 temp;
 346         struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
 347                                                   GFP_ATOMIC);
 348
 349         if (node == NULL)
 350                 return -ENOMEM;
 351
 352         node->ptr = dma_pool_alloc(hwep->td_pool, GFP_ATOMIC,
 353                                    &node->dma);
 354         if (node->ptr == NULL) {
 355                 kfree(node);
 356                 return -ENOMEM;
 357         }
 358
 359         memset(node->ptr, 0, sizeof(struct ci_hw_td));
 360         node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
 361         node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
 362         node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
 363         if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
 364                 u32 mul = hwreq->req.length / hwep->ep.maxpacket;
 365
 366                 if (hwreq->req.length == 0
 367                                 || hwreq->req.length % hwep->ep.maxpacket)
 368                         mul++;
 369                 node->ptr->token |= mul << __ffs(TD_MULTO);
 370         }
 371
 372         temp = (u32) (hwreq->req.dma + hwreq->req.actual);
 373         if (length) {
 374                 node->ptr->page[0] = cpu_to_le32(temp);
 375                 for (i = 1; i < TD_PAGE_COUNT; i++) {
 376                         u32 page = temp + i * CI_HDRC_PAGE_SIZE;
 377                         page &= ~TD_RESERVED_MASK;
 378                         node->ptr->page[i] = cpu_to_le32(page);
 379                 }
 380         }
 381
 382         hwreq->req.actual += length;
 383
 384         if (!list_empty(&hwreq->tds)) {
 385                 /* get the last entry */
 386                 lastnode = list_entry(hwreq->tds.prev,
 387                                 struct td_node, td);
 388                 lastnode->ptr->next = cpu_to_le32(node->dma);
 389         }
 390
 391         INIT_LIST_HEAD(&node->td);
 392         list_add_tail(&node->td, &hwreq->tds);
 393
 394         return 0;
 395 }
 396
 397 /**
 398  * _usb_addr: calculates endpoint address from direction & number
 399  * @ep:  endpoint
 400  */
 401 static inline u8 _usb_addr(struct ci_hw_ep *ep)
 402 {
 403         return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
 404 }
 405
 406 /**
 407  * _hardware_queue: configures a request at hardware level
 408  * @gadget: gadget
 409  * @hwep:   endpoint
 410  *
 411  * This function returns an error code
 412  */
 413 static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
 414 {
 415         struct ci_hdrc *ci = hwep->ci;
 416         int ret = 0;
 417         unsigned rest = hwreq->req.length;
 418         int pages = TD_PAGE_COUNT;
 419         struct td_node *firstnode, *lastnode;
 420
 421         /* don't queue twice */
 422         if (hwreq->req.status == -EALREADY)
 423                 return -EALREADY;
 424
 425         hwreq->req.status = -EALREADY;
 426
 427         ret = usb_gadget_map_request(&ci->gadget, &hwreq->req, hwep->dir);
 428         if (ret)
 429                 return ret;
 430
 431         /*
 432          * The first buffer could be not page aligned.
 433          * In that case we have to span into one extra td.
 434          */
 435         if (hwreq->req.dma % PAGE_SIZE)
 436                 pages--;
 437
 438         if (rest == 0)
 439                 add_td_to_list(hwep, hwreq, 0);
 440
 441         while (rest > 0) {
 442                 unsigned count = min(hwreq->req.length - hwreq->req.actual,
 443                                         (unsigned)(pages * CI_HDRC_PAGE_SIZE));
 444                 add_td_to_list(hwep, hwreq, count);
 445                 rest -= count;
 446         }
 447
 448         if (hwreq->req.zero && hwreq->req.length
 449             && (hwreq->req.length % hwep->ep.maxpacket == 0))
 450                 add_td_to_list(hwep, hwreq, 0);
 451
 452         firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
 453
 454         lastnode = list_entry(hwreq->tds.prev,
 455                 struct td_node, td);
 456
 457         lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
 458         if (!hwreq->req.no_interrupt)
 459                 lastnode->ptr->token |= cpu_to_le32(TD_IOC);
 460         wmb();
 461
 462         hwreq->req.actual = 0;
 463         if (!list_empty(&hwep->qh.queue)) {
 464                 struct ci_hw_req *hwreqprev;
 465                 int n = hw_ep_bit(hwep->num, hwep->dir);
 466                 int tmp_stat;
 467                 struct td_node *prevlastnode;
 468                 u32 next = firstnode->dma & TD_ADDR_MASK;
 469
 470                 hwreqprev = list_entry(hwep->qh.queue.prev,
 471                                 struct ci_hw_req, queue);
 472                 prevlastnode = list_entry(hwreqprev->tds.prev,
 473                                 struct td_node, td);
 474
 475                 prevlastnode->ptr->next = cpu_to_le32(next);
 476                 wmb();
 477                 if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
 478                         goto done;
 479                 do {
 480                         hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
 481                         tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
 482                 } while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
 483                 hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
 484                 if (tmp_stat)
 485                         goto done;
 486         }
 487
 488         /*  QH configuration */
 489         hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
 490         hwep->qh.ptr->td.token &=
 491                 cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
 492
 493         if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
 494                 u32 mul = hwreq->req.length / hwep->ep.maxpacket;
 495
 496                 if (hwreq->req.length == 0
 497                                 || hwreq->req.length % hwep->ep.maxpacket)
 498                         mul++;
 499                 hwep->qh.ptr->cap |= mul << __ffs(QH_MULT);
 500         }
 501
 502         wmb();   /* synchronize before ep prime */
 503
 504         ret = hw_ep_prime(ci, hwep->num, hwep->dir,
 505                            hwep->type == USB_ENDPOINT_XFER_CONTROL);
 506 done:
 507         return ret;
 508 }
 509
 510 /*
 511  * free_pending_td: remove a pending request for the endpoint
 512  * @hwep: endpoint
 513  */
 514 static void free_pending_td(struct ci_hw_ep *hwep)
 515 {
 516         struct td_node *pending = hwep->pending_td;
 517
 518         dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
 519         hwep->pending_td = NULL;
 520         kfree(pending);
 521 }
 522
 523 static int reprime_dtd(struct ci_hdrc *ci, struct ci_hw_ep *hwep,
 524                                            struct td_node *node)
 525 {
 526         hwep->qh.ptr->td.next = node->dma;
 527         hwep->qh.ptr->td.token &=
 528                 cpu_to_le32(~(TD_STATUS_HALTED | TD_STATUS_ACTIVE));
 529
 530         /* Synchronize before ep prime */
 531         wmb();
 532
 533         return hw_ep_prime(ci, hwep->num, hwep->dir,
 534                                 hwep->type == USB_ENDPOINT_XFER_CONTROL);
 535 }
 536
 537 /**
 538  * _hardware_dequeue: handles a request at hardware level
 539  * @gadget: gadget
 540  * @hwep:   endpoint
 541  *
 542  * This function returns an error code
 543  */
 544 static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
 545 {
 546         u32 tmptoken;
 547         struct td_node *node, *tmpnode;
 548         unsigned remaining_length;
 549         unsigned actual = hwreq->req.length;
 550         struct ci_hdrc *ci = hwep->ci;
 551
 552         if (hwreq->req.status != -EALREADY)
 553                 return -EINVAL;
 554
 555         hwreq->req.status = 0;
 556
 557         list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
 558                 tmptoken = le32_to_cpu(node->ptr->token);
 559                 if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
 560                         int n = hw_ep_bit(hwep->num, hwep->dir);
 561
 562                         if (ci->rev == CI_REVISION_24)
 563                                 if (!hw_read(ci, OP_ENDPTSTAT, BIT(n)))
 564                                         reprime_dtd(ci, hwep, node);
 565                         hwreq->req.status = -EALREADY;
 566                         return -EBUSY;
 567                 }
 568
 569                 remaining_length = (tmptoken & TD_TOTAL_BYTES);
 570                 remaining_length >>= __ffs(TD_TOTAL_BYTES);
 571                 actual -= remaining_length;
 572
 573                 hwreq->req.status = tmptoken & TD_STATUS;
 574                 if ((TD_STATUS_HALTED & hwreq->req.status)) {
 575                         hwreq->req.status = -EPIPE;
 576                         break;
 577                 } else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
 578                         hwreq->req.status = -EPROTO;
 579                         break;
 580                 } else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
 581                         hwreq->req.status = -EILSEQ;
 582                         break;
 583                 }
 584
 585                 if (remaining_length) {
 586                         if (hwep->dir) {
 587                                 hwreq->req.status = -EPROTO;
 588                                 break;
 589                         }
 590                 }
 591                 /*
 592                  * As the hardware could still address the freed td
 593                  * which will run the udc unusable, the cleanup of the
 594                  * td has to be delayed by one.
 595                  */
 596                 if (hwep->pending_td)
 597                         free_pending_td(hwep);
 598
 599                 hwep->pending_td = node;
 600                 list_del_init(&node->td);
 601         }
 602
 603         usb_gadget_unmap_request(&hwep->ci->gadget, &hwreq->req, hwep->dir);
 604
 605         hwreq->req.actual += actual;
 606
 607         if (hwreq->req.status)
 608                 return hwreq->req.status;
 609
 610         return hwreq->req.actual;
 611 }
 612
 613 /**
 614  * _ep_nuke: dequeues all endpoint requests
 615  * @hwep: endpoint
 616  *
 617  * This function returns an error code
 618  * Caller must hold lock
 619  */
 620 static int _ep_nuke(struct ci_hw_ep *hwep)
 621 __releases(hwep->lock)
 622 __acquires(hwep->lock)
 623 {
 624         struct td_node *node, *tmpnode;
 625         if (hwep == NULL)
 626                 return -EINVAL;
 627
 628         hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
 629
 630         while (!list_empty(&hwep->qh.queue)) {
 631
 632                 /* pop oldest request */
 633                 struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
 634                                                      struct ci_hw_req, queue);
 635
 636                 list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
 637                         dma_pool_free(hwep->td_pool, node->ptr, node->dma);
 638                         list_del_init(&node->td);
 639                         node->ptr = NULL;
 640                         kfree(node);
 641                 }
 642
 643                 list_del_init(&hwreq->queue);
 644                 hwreq->req.status = -ESHUTDOWN;
 645
 646                 if (hwreq->req.complete != NULL) {
 647                         spin_unlock(hwep->lock);
 648                         usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
 649                         spin_lock(hwep->lock);
 650                 }
 651         }
 652
 653         if (hwep->pending_td)
 654                 free_pending_td(hwep);
 655
 656         return 0;
 657 }
 658
 659 /**
 660  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
 661  * @gadget: gadget
 662  *
 663  * This function returns an error code
 664  */
 665 static int _gadget_stop_activity(struct usb_gadget *gadget)
 666 {
 667         struct usb_ep *ep;
 668         struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
 669         unsigned long flags;
 670
 671         spin_lock_irqsave(&ci->lock, flags);
 672         ci->gadget.speed = USB_SPEED_UNKNOWN;
 673         ci->remote_wakeup = 0;
 674         ci->suspended = 0;
 675         spin_unlock_irqrestore(&ci->lock, flags);
 676
 677         /* flush all endpoints */
 678         gadget_for_each_ep(ep, gadget) {
 679                 usb_ep_fifo_flush(ep);
 680         }
 681         usb_ep_fifo_flush(&ci->ep0out->ep);
 682         usb_ep_fifo_flush(&ci->ep0in->ep);
 683
 684         /* make sure to disable all endpoints */
 685         gadget_for_each_ep(ep, gadget) {
 686                 usb_ep_disable(ep);
 687         }
 688
 689         if (ci->status != NULL) {
 690                 usb_ep_free_request(&ci->ep0in->ep, ci->status);
 691                 ci->status = NULL;
 692         }
 693
 694         return 0;
 695 }
 696
 697 /******************************************************************************
 698  * ISR block
 699  *****************************************************************************/
 700 /**
 701  * isr_reset_handler: USB reset interrupt handler
 702  * @ci: UDC device
 703  *
 704  * This function resets USB engine after a bus reset occurred
 705  */
 706 static void isr_reset_handler(struct ci_hdrc *ci)
 707 __releases(ci->lock)
 708 __acquires(ci->lock)
 709 {
 710         int retval;
 711
 712         spin_unlock(&ci->lock);
 713         if (ci->gadget.speed != USB_SPEED_UNKNOWN)
 714                 usb_gadget_udc_reset(&ci->gadget, ci->driver);
 715
 716         retval = _gadget_stop_activity(&ci->gadget);
 717         if (retval)
 718                 goto done;
 719
 720         retval = hw_usb_reset(ci);
 721         if (retval)
 722                 goto done;
 723
 724         ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
 725         if (ci->status == NULL)
 726                 retval = -ENOMEM;
 727
 728 done:
 729         spin_lock(&ci->lock);
 730
 731         if (retval)
 732                 dev_err(ci->dev, "error: %i\n", retval);
 733 }
 734
 735 /**
 736  * isr_get_status_complete: get_status request complete function
 737  * @ep:  endpoint
 738  * @req: request handled
 739  *
 740  * Caller must release lock
 741  */
 742 static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
 743 {
 744         if (ep == NULL || req == NULL)
 745                 return;
 746
 747         kfree(req->buf);
 748         usb_ep_free_request(ep, req);
 749 }
 750
 751 /**
 752  * _ep_queue: queues (submits) an I/O request to an endpoint
 753  *
 754  * Caller must hold lock
 755  */
 756 static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
 757                     gfp_t __maybe_unused gfp_flags)
 758 {
 759         struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
 760         struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
 761         struct ci_hdrc *ci = hwep->ci;
 762         int retval = 0;
 763
 764         if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
 765                 return -EINVAL;
 766
 767         if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
 768                 if (req->length)
 769                         hwep = (ci->ep0_dir == RX) ?
 770                                ci->ep0out : ci->ep0in;
 771                 if (!list_empty(&hwep->qh.queue)) {
 772                         _ep_nuke(hwep);
 773                         retval = -EOVERFLOW;
 774                         dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
 775                                  _usb_addr(hwep));
 776                 }
 777         }
 778
 779         if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
 780             hwreq->req.length > (1 + hwep->ep.mult) * hwep->ep.maxpacket) {
 781                 dev_err(hwep->ci->dev, "request length too big for isochronous\n");
 782                 return -EMSGSIZE;
 783         }
 784
 785         /* first nuke then test link, e.g. previous status has not sent */
 786         if (!list_empty(&hwreq->queue)) {
 787                 dev_err(hwep->ci->dev, "request already in queue\n");
 788                 return -EBUSY;
 789         }
 790
 791         /* push request */
 792         hwreq->req.status = -EINPROGRESS;
 793         hwreq->req.actual = 0;
 794
 795         retval = _hardware_enqueue(hwep, hwreq);
 796
 797         if (retval == -EALREADY)
 798                 retval = 0;
 799         if (!retval)
 800                 list_add_tail(&hwreq->queue, &hwep->qh.queue);
 801
 802         return retval;
 803 }
 804
 805 /**
 806  * isr_get_status_response: get_status request response
 807  * @ci: ci struct
 808  * @setup: setup request packet
 809  *
 810  * This function returns an error code
 811  */
 812 static int isr_get_status_response(struct ci_hdrc *ci,
 813                                    struct usb_ctrlrequest *setup)
 814 __releases(hwep->lock)
 815 __acquires(hwep->lock)
 816 {
 817         struct ci_hw_ep *hwep = ci->ep0in;
 818         struct usb_request *req = NULL;
 819         gfp_t gfp_flags = GFP_ATOMIC;
 820         int dir, num, retval;
 821
 822         if (hwep == NULL || setup == NULL)
 823                 return -EINVAL;
 824
 825         spin_unlock(hwep->lock);
 826         req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
 827         spin_lock(hwep->lock);
 828         if (req == NULL)
 829                 return -ENOMEM;
 830
 831         req->complete = isr_get_status_complete;
 832         req->length   = 2;
 833         req->buf      = kzalloc(req->length, gfp_flags);
 834         if (req->buf == NULL) {
 835                 retval = -ENOMEM;
 836                 goto err_free_req;
 837         }
 838
 839         if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
 840                 *(u16 *)req->buf = (ci->remote_wakeup << 1) |
 841                         ci->gadget.is_selfpowered;
 842         } else if ((setup->bRequestType & USB_RECIP_MASK) \
 843                    == USB_RECIP_ENDPOINT) {
 844                 dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
 845                         TX : RX;
 846                 num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
 847                 *(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
 848         }
 849         /* else do nothing; reserved for future use */
 850
 851         retval = _ep_queue(&hwep->ep, req, gfp_flags);
 852         if (retval)
 853                 goto err_free_buf;
 854
 855         return 0;
 856
 857  err_free_buf:
 858         kfree(req->buf);
 859  err_free_req:
 860         spin_unlock(hwep->lock);
 861         usb_ep_free_request(&hwep->ep, req);
 862         spin_lock(hwep->lock);
 863         return retval;
 864 }
 865
 866 /**
 867  * isr_setup_status_complete: setup_status request complete function
 868  * @ep:  endpoint
 869  * @req: request handled
 870  *
 871  * Caller must release lock. Put the port in test mode if test mode
 872  * feature is selected.
 873  */
 874 static void
 875 isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
 876 {
 877         struct ci_hdrc *ci = req->context;
 878         unsigned long flags;
 879
 880         if (ci->setaddr) {
 881                 hw_usb_set_address(ci, ci->address);
 882                 ci->setaddr = false;
 883                 if (ci->address)
 884                         usb_gadget_set_state(&ci->gadget, USB_STATE_ADDRESS);
 885         }
 886
 887         spin_lock_irqsave(&ci->lock, flags);
 888         if (ci->test_mode)
 889                 hw_port_test_set(ci, ci->test_mode);
 890         spin_unlock_irqrestore(&ci->lock, flags);
 891 }
 892
 893 /**
 894  * isr_setup_status_phase: queues the status phase of a setup transation
 895  * @ci: ci struct
 896  *
 897  * This function returns an error code
 898  */
 899 static int isr_setup_status_phase(struct ci_hdrc *ci)
 900 {
 901         int retval;
 902         struct ci_hw_ep *hwep;
 903
 904         hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
 905         ci->status->context = ci;
 906         ci->status->complete = isr_setup_status_complete;
 907
 908         retval = _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
 909
 910         return retval;
 911 }
 912
 913 /**
 914  * isr_tr_complete_low: transaction complete low level handler
 915  * @hwep: endpoint
 916  *
 917  * This function returns an error code
 918  * Caller must hold lock
 919  */
 920 static int isr_tr_complete_low(struct ci_hw_ep *hwep)
 921 __releases(hwep->lock)
 922 __acquires(hwep->lock)
 923 {
 924         struct ci_hw_req *hwreq, *hwreqtemp;
 925         struct ci_hw_ep *hweptemp = hwep;
 926         int retval = 0;
 927
 928         list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
 929                         queue) {
 930                 retval = _hardware_dequeue(hwep, hwreq);
 931                 if (retval < 0)
 932                         break;
 933                 list_del_init(&hwreq->queue);
 934                 if (hwreq->req.complete != NULL) {
 935                         spin_unlock(hwep->lock);
 936                         if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
 937                                         hwreq->req.length)
 938                                 hweptemp = hwep->ci->ep0in;
 939                         usb_gadget_giveback_request(&hweptemp->ep, &hwreq->req);
 940                         spin_lock(hwep->lock);
 941                 }
 942         }
 943
 944         if (retval == -EBUSY)
 945                 retval = 0;
 946
 947         return retval;
 948 }
 949
 950 static int otg_a_alt_hnp_support(struct ci_hdrc *ci)
 951 {
 952         dev_warn(&ci->gadget.dev,
 953                 "connect the device to an alternate port if you want HNP\n");
 954         return isr_setup_status_phase(ci);
 955 }
 956
 957 /**
 958  * isr_setup_packet_handler: setup packet handler
 959  * @ci: UDC descriptor
 960  *
 961  * This function handles setup packet
 962  */
 963 static void isr_setup_packet_handler(struct ci_hdrc *ci)
 964 __releases(ci->lock)
 965 __acquires(ci->lock)
 966 {
 967         struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
 968         struct usb_ctrlrequest req;
 969         int type, num, dir, err = -EINVAL;
 970         u8 tmode = 0;
 971
 972         /*
 973          * Flush data and handshake transactions of previous
 974          * setup packet.
 975          */
 976         _ep_nuke(ci->ep0out);
 977         _ep_nuke(ci->ep0in);
 978
 979         /* read_setup_packet */
 980         do {
 981                 hw_test_and_set_setup_guard(ci);
 982                 memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
 983         } while (!hw_test_and_clear_setup_guard(ci));
 984
 985         type = req.bRequestType;
 986
 987         ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
 988
 989         switch (req.bRequest) {
 990         case USB_REQ_CLEAR_FEATURE:
 991                 if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
 992                                 le16_to_cpu(req.wValue) ==
 993                                 USB_ENDPOINT_HALT) {
 994                         if (req.wLength != 0)
 995                                 break;
 996                         num  = le16_to_cpu(req.wIndex);
 997                         dir = num & USB_ENDPOINT_DIR_MASK;
 998                         num &= USB_ENDPOINT_NUMBER_MASK;
 999                         if (dir) /* TX */
1000                                 num += ci->hw_ep_max / 2;
1001                         if (!ci->ci_hw_ep[num].wedge) {
1002                                 spin_unlock(&ci->lock);
1003                                 err = usb_ep_clear_halt(
1004                                         &ci->ci_hw_ep[num].ep);
1005                                 spin_lock(&ci->lock);
1006                                 if (err)
1007                                         break;
1008                         }
1009                         err = isr_setup_status_phase(ci);
1010                 } else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1011                                 le16_to_cpu(req.wValue) ==
1012                                 USB_DEVICE_REMOTE_WAKEUP) {
1013                         if (req.wLength != 0)
1014                                 break;
1015                         ci->remote_wakeup = 0;
1016                         err = isr_setup_status_phase(ci);
1017                 } else {
1018                         goto delegate;
1019                 }
1020                 break;
1021         case USB_REQ_GET_STATUS:
1022                 if (type != (USB_DIR_IN|USB_RECIP_DEVICE)   &&
1023                     type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1024                     type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1025                         goto delegate;
1026                 if (le16_to_cpu(req.wLength) != 2 ||
1027                     le16_to_cpu(req.wValue)  != 0)
1028                         break;
1029                 err = isr_get_status_response(ci, &req);
1030                 break;
1031         case USB_REQ_SET_ADDRESS:
1032                 if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1033                         goto delegate;
1034                 if (le16_to_cpu(req.wLength) != 0 ||
1035                     le16_to_cpu(req.wIndex)  != 0)
1036                         break;
1037                 ci->address = (u8)le16_to_cpu(req.wValue);
1038                 ci->setaddr = true;
1039                 err = isr_setup_status_phase(ci);
1040                 break;
1041         case USB_REQ_SET_FEATURE:
1042                 if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1043                                 le16_to_cpu(req.wValue) ==
1044                                 USB_ENDPOINT_HALT) {
1045                         if (req.wLength != 0)
1046                                 break;
1047                         num  = le16_to_cpu(req.wIndex);
1048                         dir = num & USB_ENDPOINT_DIR_MASK;
1049                         num &= USB_ENDPOINT_NUMBER_MASK;
1050                         if (dir) /* TX */
1051                                 num += ci->hw_ep_max / 2;
1052
1053                         spin_unlock(&ci->lock);
1054                         err = usb_ep_set_halt(&ci->ci_hw_ep[num].ep);
1055                         spin_lock(&ci->lock);
1056                         if (!err)
1057                                 isr_setup_status_phase(ci);
1058                 } else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1059                         if (req.wLength != 0)
1060                                 break;
1061                         switch (le16_to_cpu(req.wValue)) {
1062                         case USB_DEVICE_REMOTE_WAKEUP:
1063                                 ci->remote_wakeup = 1;
1064                                 err = isr_setup_status_phase(ci);
1065                                 break;
1066                         case USB_DEVICE_TEST_MODE:
1067                                 tmode = le16_to_cpu(req.wIndex) >> 8;
1068                                 switch (tmode) {
1069                                 case TEST_J:
1070                                 case TEST_K:
1071                                 case TEST_SE0_NAK:
1072                                 case TEST_PACKET:
1073                                 case TEST_FORCE_EN:
1074                                         ci->test_mode = tmode;
1075                                         err = isr_setup_status_phase(
1076                                                         ci);
1077                                         break;
1078                                 default:
1079                                         break;
1080                                 }
1081                                 break;
1082                         case USB_DEVICE_B_HNP_ENABLE:
1083                                 if (ci_otg_is_fsm_mode(ci)) {
1084                                         ci->gadget.b_hnp_enable = 1;
1085                                         err = isr_setup_status_phase(
1086                                                         ci);
1087                                 }
1088                                 break;
1089                         case USB_DEVICE_A_ALT_HNP_SUPPORT:
1090                                 if (ci_otg_is_fsm_mode(ci))
1091                                         err = otg_a_alt_hnp_support(ci);
1092                                 break;
1093                         default:
1094                                 goto delegate;
1095                         }
1096                 } else {
1097                         goto delegate;
1098                 }
1099                 break;
1100         default:
1101 delegate:
1102                 if (req.wLength == 0)   /* no data phase */
1103                         ci->ep0_dir = TX;
1104
1105                 spin_unlock(&ci->lock);
1106                 err = ci->driver->setup(&ci->gadget, &req);
1107                 spin_lock(&ci->lock);
1108                 break;
1109         }
1110
1111         if (err < 0) {
1112                 spin_unlock(&ci->lock);
1113                 if (usb_ep_set_halt(&hwep->ep))
1114                         dev_err(ci->dev, "error: ep_set_halt\n");
1115                 spin_lock(&ci->lock);
1116         }
1117 }
1118
1119 /**
1120  * isr_tr_complete_handler: transaction complete interrupt handler
1121  * @ci: UDC descriptor
1122  *
1123  * This function handles traffic events
1124  */
1125 static void isr_tr_complete_handler(struct ci_hdrc *ci)
1126 __releases(ci->lock)
1127 __acquires(ci->lock)
1128 {
1129         unsigned i;
1130         int err;
1131
1132         for (i = 0; i < ci->hw_ep_max; i++) {
1133                 struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
1134
1135                 if (hwep->ep.desc == NULL)
1136                         continue;   /* not configured */
1137
1138                 if (hw_test_and_clear_complete(ci, i)) {
1139                         err = isr_tr_complete_low(hwep);
1140                         if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1141                                 if (err > 0)   /* needs status phase */
1142                                         err = isr_setup_status_phase(ci);
1143                                 if (err < 0) {
1144                                         spin_unlock(&ci->lock);
1145                                         if (usb_ep_set_halt(&hwep->ep))
1146                                                 dev_err(ci->dev,
1147                                                         "error: ep_set_halt\n");
1148                                         spin_lock(&ci->lock);
1149                                 }
1150                         }
1151                 }
1152
1153                 /* Only handle setup packet below */
1154                 if (i == 0 &&
1155                         hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
1156                         isr_setup_packet_handler(ci);
1157         }
1158 }
1159
1160 /******************************************************************************
1161  * ENDPT block
1162  *****************************************************************************/
1163 /**
1164  * ep_enable: configure endpoint, making it usable
1165  *
1166  * Check usb_ep_enable() at "usb_gadget.h" for details
1167  */
1168 static int ep_enable(struct usb_ep *ep,
1169                      const struct usb_endpoint_descriptor *desc)
1170 {
1171         struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1172         int retval = 0;
1173         unsigned long flags;
1174         u32 cap = 0;
1175
1176         if (ep == NULL || desc == NULL)
1177                 return -EINVAL;
1178
1179         spin_lock_irqsave(hwep->lock, flags);
1180
1181         /* only internal SW should enable ctrl endpts */
1182
1183         if (!list_empty(&hwep->qh.queue)) {
1184                 dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1185                 spin_unlock_irqrestore(hwep->lock, flags);
1186                 return -EBUSY;
1187         }
1188
1189         hwep->ep.desc = desc;
1190
1191         hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1192         hwep->num  = usb_endpoint_num(desc);
1193         hwep->type = usb_endpoint_type(desc);
1194
1195         hwep->ep.maxpacket = usb_endpoint_maxp(desc) & 0x07ff;
1196         hwep->ep.mult = QH_ISO_MULT(usb_endpoint_maxp(desc));
1197
1198         if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1199                 cap |= QH_IOS;
1200
1201         cap |= QH_ZLT;
1202         cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1203         /*
1204          * For ISO-TX, we set mult at QH as the largest value, and use
1205          * MultO at TD as real mult value.
1206          */
1207         if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1208                 cap |= 3 << __ffs(QH_MULT);
1209
1210         hwep->qh.ptr->cap = cpu_to_le32(cap);
1211
1212         hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1213
1214         if (hwep->num != 0 && hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1215                 dev_err(hwep->ci->dev, "Set control xfer at non-ep0\n");
1216                 retval = -EINVAL;
1217         }
1218
1219         /*
1220          * Enable endpoints in the HW other than ep0 as ep0
1221          * is always enabled
1222          */
1223         if (hwep->num)
1224                 retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1225                                        hwep->type);
1226
1227         spin_unlock_irqrestore(hwep->lock, flags);
1228         return retval;
1229 }
1230
1231 /**
1232  * ep_disable: endpoint is no longer usable
1233  *
1234  * Check usb_ep_disable() at "usb_gadget.h" for details
1235  */
1236 static int ep_disable(struct usb_ep *ep)
1237 {
1238         struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1239         int direction, retval = 0;
1240         unsigned long flags;
1241
1242         if (ep == NULL)
1243                 return -EINVAL;
1244         else if (hwep->ep.desc == NULL)
1245                 return -EBUSY;
1246
1247         spin_lock_irqsave(hwep->lock, flags);
1248
1249         /* only internal SW should disable ctrl endpts */
1250
1251         direction = hwep->dir;
1252         do {
1253                 retval |= _ep_nuke(hwep);
1254                 retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1255
1256                 if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1257                         hwep->dir = (hwep->dir == TX) ? RX : TX;
1258
1259         } while (hwep->dir != direction);
1260
1261         hwep->ep.desc = NULL;
1262
1263         spin_unlock_irqrestore(hwep->lock, flags);
1264         return retval;
1265 }
1266
1267 /**
1268  * ep_alloc_request: allocate a request object to use with this endpoint
1269  *
1270  * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1271  */
1272 static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1273 {
1274         struct ci_hw_req *hwreq = NULL;
1275
1276         if (ep == NULL)
1277                 return NULL;
1278
1279         hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1280         if (hwreq != NULL) {
1281                 INIT_LIST_HEAD(&hwreq->queue);
1282                 INIT_LIST_HEAD(&hwreq->tds);
1283         }
1284
1285         return (hwreq == NULL) ? NULL : &hwreq->req;
1286 }
1287
1288 /**
1289  * ep_free_request: frees a request object
1290  *
1291  * Check usb_ep_free_request() at "usb_gadget.h" for details
1292  */
1293 static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1294 {
1295         struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1296         struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1297         struct td_node *node, *tmpnode;
1298         unsigned long flags;
1299
1300         if (ep == NULL || req == NULL) {
1301                 return;
1302         } else if (!list_empty(&hwreq->queue)) {
1303                 dev_err(hwep->ci->dev, "freeing queued request\n");
1304                 return;
1305         }
1306
1307         spin_lock_irqsave(hwep->lock, flags);
1308
1309         list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1310                 dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1311                 list_del_init(&node->td);
1312                 node->ptr = NULL;
1313                 kfree(node);
1314         }
1315
1316         kfree(hwreq);
1317
1318         spin_unlock_irqrestore(hwep->lock, flags);
1319 }
1320
1321 /**
1322  * ep_queue: queues (submits) an I/O request to an endpoint
1323  *
1324  * Check usb_ep_queue()* at usb_gadget.h" for details
1325  */
1326 static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1327                     gfp_t __maybe_unused gfp_flags)
1328 {
1329         struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1330         int retval = 0;
1331         unsigned long flags;
1332
1333         if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1334                 return -EINVAL;
1335
1336         spin_lock_irqsave(hwep->lock, flags);
1337         retval = _ep_queue(ep, req, gfp_flags);
1338         spin_unlock_irqrestore(hwep->lock, flags);
1339         return retval;
1340 }
1341
1342 /**
1343  * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1344  *
1345  * Check usb_ep_dequeue() at "usb_gadget.h" for details
1346  */
1347 static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1348 {
1349         struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1350         struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1351         unsigned long flags;
1352         struct td_node *node, *tmpnode;
1353
1354         if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1355                 hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1356                 list_empty(&hwep->qh.queue))
1357                 return -EINVAL;
1358
1359         spin_lock_irqsave(hwep->lock, flags);
1360
1361         hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1362
1363         list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1364                 dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1365                 list_del(&node->td);
1366                 kfree(node);
1367         }
1368
1369         /* pop request */
1370         list_del_init(&hwreq->queue);
1371
1372         usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1373
1374         req->status = -ECONNRESET;
1375
1376         if (hwreq->req.complete != NULL) {
1377                 spin_unlock(hwep->lock);
1378                 usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
1379                 spin_lock(hwep->lock);
1380         }
1381
1382         spin_unlock_irqrestore(hwep->lock, flags);
1383         return 0;
1384 }
1385
1386 /**
1387  * ep_set_halt: sets the endpoint halt feature
1388  *
1389  * Check usb_ep_set_halt() at "usb_gadget.h" for details
1390  */
1391 static int ep_set_halt(struct usb_ep *ep, int value)
1392 {
1393         struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1394         int direction, retval = 0;
1395         unsigned long flags;
1396
1397         if (ep == NULL || hwep->ep.desc == NULL)
1398                 return -EINVAL;
1399
1400         if (usb_endpoint_xfer_isoc(hwep->ep.desc))
1401                 return -EOPNOTSUPP;
1402
1403         spin_lock_irqsave(hwep->lock, flags);
1404
1405 #ifndef STALL_IN
1406         /* g_file_storage MS compliant but g_zero fails chapter 9 compliance */
1407         if (value && hwep->type == USB_ENDPOINT_XFER_BULK && hwep->dir == TX &&
1408             !list_empty(&hwep->qh.queue)) {
1409                 spin_unlock_irqrestore(hwep->lock, flags);
1410                 return -EAGAIN;
1411         }
1412 #endif
1413
1414         direction = hwep->dir;
1415         do {
1416                 retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
1417
1418                 if (!value)
1419                         hwep->wedge = 0;
1420
1421                 if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1422                         hwep->dir = (hwep->dir == TX) ? RX : TX;
1423
1424         } while (hwep->dir != direction);
1425
1426         spin_unlock_irqrestore(hwep->lock, flags);
1427         return retval;
1428 }
1429
1430 /**
1431  * ep_set_wedge: sets the halt feature and ignores clear requests
1432  *
1433  * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1434  */
1435 static int ep_set_wedge(struct usb_ep *ep)
1436 {
1437         struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1438         unsigned long flags;
1439
1440         if (ep == NULL || hwep->ep.desc == NULL)
1441                 return -EINVAL;
1442
1443         spin_lock_irqsave(hwep->lock, flags);
1444         hwep->wedge = 1;
1445         spin_unlock_irqrestore(hwep->lock, flags);
1446
1447         return usb_ep_set_halt(ep);
1448 }
1449
1450 /**
1451  * ep_fifo_flush: flushes contents of a fifo
1452  *
1453  * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1454  */
1455 static void ep_fifo_flush(struct usb_ep *ep)
1456 {
1457         struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1458         unsigned long flags;
1459
1460         if (ep == NULL) {
1461                 dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1462                 return;
1463         }
1464
1465         spin_lock_irqsave(hwep->lock, flags);
1466
1467         hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1468
1469         spin_unlock_irqrestore(hwep->lock, flags);
1470 }
1471
1472 /**
1473  * Endpoint-specific part of the API to the USB controller hardware
1474  * Check "usb_gadget.h" for details
1475  */
1476 static const struct usb_ep_ops usb_ep_ops = {
1477         .enable        = ep_enable,
1478         .disable       = ep_disable,
1479         .alloc_request = ep_alloc_request,
1480         .free_request  = ep_free_request,
1481         .queue         = ep_queue,
1482         .dequeue       = ep_dequeue,
1483         .set_halt      = ep_set_halt,
1484         .set_wedge     = ep_set_wedge,
1485         .fifo_flush    = ep_fifo_flush,
1486 };
1487
1488 /******************************************************************************
1489  * GADGET block
1490  *****************************************************************************/
1491 static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1492 {
1493         struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1494         unsigned long flags;
1495         int gadget_ready = 0;
1496
1497         spin_lock_irqsave(&ci->lock, flags);
1498         ci->vbus_active = is_active;
1499         if (ci->driver)
1500                 gadget_ready = 1;
1501         spin_unlock_irqrestore(&ci->lock, flags);
1502
1503         if (gadget_ready) {
1504                 if (is_active) {
1505                         pm_runtime_get_sync(&_gadget->dev);
1506                         hw_device_reset(ci);
1507                         hw_device_state(ci, ci->ep0out->qh.dma);
1508                         usb_gadget_set_state(_gadget, USB_STATE_POWERED);
1509                         usb_udc_vbus_handler(_gadget, true);
1510                 } else {
1511                         usb_udc_vbus_handler(_gadget, false);
1512                         if (ci->driver)
1513                                 ci->driver->disconnect(&ci->gadget);
1514                         hw_device_state(ci, 0);
1515                         if (ci->platdata->notify_event)
1516                                 ci->platdata->notify_event(ci,
1517                                 CI_HDRC_CONTROLLER_STOPPED_EVENT);
1518                         _gadget_stop_activity(&ci->gadget);
1519                         pm_runtime_put_sync(&_gadget->dev);
1520                         usb_gadget_set_state(_gadget, USB_STATE_NOTATTACHED);
1521                 }
1522         }
1523
1524         return 0;
1525 }
1526
1527 static int ci_udc_wakeup(struct usb_gadget *_gadget)
1528 {
1529         struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1530         unsigned long flags;
1531         int ret = 0;
1532
1533         spin_lock_irqsave(&ci->lock, flags);
1534         if (!ci->remote_wakeup) {
1535                 ret = -EOPNOTSUPP;
1536                 goto out;
1537         }
1538         if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1539                 ret = -EINVAL;
1540                 goto out;
1541         }
1542         hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1543 out:
1544         spin_unlock_irqrestore(&ci->lock, flags);
1545         return ret;
1546 }
1547
1548 static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1549 {
1550         struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1551
1552         if (ci->usb_phy)
1553                 return usb_phy_set_power(ci->usb_phy, ma);
1554         return -ENOTSUPP;
1555 }
1556
1557 static int ci_udc_selfpowered(struct usb_gadget *_gadget, int is_on)
1558 {
1559         struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1560         struct ci_hw_ep *hwep = ci->ep0in;
1561         unsigned long flags;
1562
1563         spin_lock_irqsave(hwep->lock, flags);
1564         _gadget->is_selfpowered = (is_on != 0);
1565         spin_unlock_irqrestore(hwep->lock, flags);
1566
1567         return 0;
1568 }
1569
1570 /* Change Data+ pullup status
1571  * this func is used by usb_gadget_connect/disconnet
1572  */
1573 static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1574 {
1575         struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1576
1577         /* Data+ pullup controlled by OTG state machine in OTG fsm mode */
1578         if (ci_otg_is_fsm_mode(ci))
1579                 return 0;
1580
1581         pm_runtime_get_sync(&ci->gadget.dev);
1582         if (is_on)
1583                 hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1584         else
1585                 hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1586         pm_runtime_put_sync(&ci->gadget.dev);
1587
1588         return 0;
1589 }
1590
1591 static int ci_udc_start(struct usb_gadget *gadget,
1592                          struct usb_gadget_driver *driver);
1593 static int ci_udc_stop(struct usb_gadget *gadget);
1594 /**
1595  * Device operations part of the API to the USB controller hardware,
1596  * which don't involve endpoints (or i/o)
1597  * Check  "usb_gadget.h" for details
1598  */
1599 static const struct usb_gadget_ops usb_gadget_ops = {
1600         .vbus_session   = ci_udc_vbus_session,
1601         .wakeup         = ci_udc_wakeup,
1602         .set_selfpowered        = ci_udc_selfpowered,
1603         .pullup         = ci_udc_pullup,
1604         .vbus_draw      = ci_udc_vbus_draw,
1605         .udc_start      = ci_udc_start,
1606         .udc_stop       = ci_udc_stop,
1607 };
1608
1609 static int init_eps(struct ci_hdrc *ci)
1610 {
1611         int retval = 0, i, j;
1612
1613         for (i = 0; i < ci->hw_ep_max/2; i++)
1614                 for (j = RX; j <= TX; j++) {
1615                         int k = i + j * ci->hw_ep_max/2;
1616                         struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1617
1618                         scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1619                                         (j == TX)  ? "in" : "out");
1620
1621                         hwep->ci          = ci;
1622                         hwep->lock         = &ci->lock;
1623                         hwep->td_pool      = ci->td_pool;
1624
1625                         hwep->ep.name      = hwep->name;
1626                         hwep->ep.ops       = &usb_ep_ops;
1627                         /*
1628                          * for ep0: maxP defined in desc, for other
1629                          * eps, maxP is set by epautoconfig() called
1630                          * by gadget layer
1631                          */
1632                         usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1633
1634                         INIT_LIST_HEAD(&hwep->qh.queue);
1635                         hwep->qh.ptr = dma_pool_alloc(ci->qh_pool, GFP_KERNEL,
1636                                                      &hwep->qh.dma);
1637                         if (hwep->qh.ptr == NULL)
1638                                 retval = -ENOMEM;
1639                         else
1640                                 memset(hwep->qh.ptr, 0, sizeof(*hwep->qh.ptr));
1641
1642                         /*
1643                          * set up shorthands for ep0 out and in endpoints,
1644                          * don't add to gadget's ep_list
1645                          */
1646                         if (i == 0) {
1647                                 if (j == RX)
1648                                         ci->ep0out = hwep;
1649                                 else
1650                                         ci->ep0in = hwep;
1651
1652                                 usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1653                                 continue;
1654                         }
1655
1656                         list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1657                 }
1658
1659         return retval;
1660 }
1661
1662 static void destroy_eps(struct ci_hdrc *ci)
1663 {
1664         int i;
1665
1666         for (i = 0; i < ci->hw_ep_max; i++) {
1667                 struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1668
1669                 if (hwep->pending_td)
1670                         free_pending_td(hwep);
1671                 dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1672         }
1673 }
1674
1675 /**
1676  * ci_udc_start: register a gadget driver
1677  * @gadget: our gadget
1678  * @driver: the driver being registered
1679  *
1680  * Interrupts are enabled here.
1681  */
1682 static int ci_udc_start(struct usb_gadget *gadget,
1683                          struct usb_gadget_driver *driver)
1684 {
1685         struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1686         unsigned long flags;
1687         int retval = -ENOMEM;
1688
1689         if (driver->disconnect == NULL)
1690                 return -EINVAL;
1691
1692
1693         ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1694         retval = usb_ep_enable(&ci->ep0out->ep);
1695         if (retval)
1696                 return retval;
1697
1698         ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1699         retval = usb_ep_enable(&ci->ep0in->ep);
1700         if (retval)
1701                 return retval;
1702
1703         ci->driver = driver;
1704
1705         /* Start otg fsm for B-device */
1706         if (ci_otg_is_fsm_mode(ci) && ci->fsm.id) {
1707                 ci_hdrc_otg_fsm_start(ci);
1708                 return retval;
1709         }
1710
1711         pm_runtime_get_sync(&ci->gadget.dev);
1712         if (ci->vbus_active) {
1713                 spin_lock_irqsave(&ci->lock, flags);
1714                 hw_device_reset(ci);
1715         } else {
1716                 usb_udc_vbus_handler(&ci->gadget, false);
1717                 pm_runtime_put_sync(&ci->gadget.dev);
1718                 return retval;
1719         }
1720
1721         retval = hw_device_state(ci, ci->ep0out->qh.dma);
1722         spin_unlock_irqrestore(&ci->lock, flags);
1723         if (retval)
1724                 pm_runtime_put_sync(&ci->gadget.dev);
1725
1726         return retval;
1727 }
1728
1729 /**
1730  * ci_udc_stop: unregister a gadget driver
1731  */
1732 static int ci_udc_stop(struct usb_gadget *gadget)
1733 {
1734         struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1735         unsigned long flags;
1736
1737         spin_lock_irqsave(&ci->lock, flags);
1738
1739         if (ci->vbus_active) {
1740                 hw_device_state(ci, 0);
1741                 if (ci->platdata->notify_event)
1742                         ci->platdata->notify_event(ci,
1743                         CI_HDRC_CONTROLLER_STOPPED_EVENT);
1744                 spin_unlock_irqrestore(&ci->lock, flags);
1745                 _gadget_stop_activity(&ci->gadget);
1746                 spin_lock_irqsave(&ci->lock, flags);
1747                 pm_runtime_put(&ci->gadget.dev);
1748         }
1749
1750         ci->driver = NULL;
1751         spin_unlock_irqrestore(&ci->lock, flags);
1752
1753         return 0;
1754 }
1755
1756 /******************************************************************************
1757  * BUS block
1758  *****************************************************************************/
1759 /**
1760  * udc_irq: ci interrupt handler
1761  *
1762  * This function returns IRQ_HANDLED if the IRQ has been handled
1763  * It locks access to registers
1764  */
1765 static irqreturn_t udc_irq(struct ci_hdrc *ci)
1766 {
1767         irqreturn_t retval;
1768         u32 intr;
1769
1770         if (ci == NULL)
1771                 return IRQ_HANDLED;
1772
1773         spin_lock(&ci->lock);
1774
1775         if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1776                 if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1777                                 USBMODE_CM_DC) {
1778                         spin_unlock(&ci->lock);
1779                         return IRQ_NONE;
1780                 }
1781         }
1782         intr = hw_test_and_clear_intr_active(ci);
1783
1784         if (intr) {
1785                 /* order defines priority - do NOT change it */
1786                 if (USBi_URI & intr)
1787                         isr_reset_handler(ci);
1788
1789                 if (USBi_PCI & intr) {
1790                         ci->gadget.speed = hw_port_is_high_speed(ci) ?
1791                                 USB_SPEED_HIGH : USB_SPEED_FULL;
1792                         if (ci->suspended && ci->driver->resume) {
1793                                 spin_unlock(&ci->lock);
1794                                 ci->driver->resume(&ci->gadget);
1795                                 spin_lock(&ci->lock);
1796                                 ci->suspended = 0;
1797                         }
1798                 }
1799
1800                 if (USBi_UI  & intr)
1801                         isr_tr_complete_handler(ci);
1802
1803                 if (USBi_SLI & intr) {
1804                         if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
1805                             ci->driver->suspend) {
1806                                 ci->suspended = 1;
1807                                 spin_unlock(&ci->lock);
1808                                 ci->driver->suspend(&ci->gadget);
1809                                 usb_gadget_set_state(&ci->gadget,
1810                                                 USB_STATE_SUSPENDED);
1811                                 spin_lock(&ci->lock);
1812                         }
1813                 }
1814                 retval = IRQ_HANDLED;
1815         } else {
1816                 retval = IRQ_NONE;
1817         }
1818         spin_unlock(&ci->lock);
1819
1820         return retval;
1821 }
1822
1823 /**
1824  * udc_start: initialize gadget role
1825  * @ci: chipidea controller
1826  */
1827 static int udc_start(struct ci_hdrc *ci)
1828 {
1829         struct device *dev = ci->dev;
1830         int retval = 0;
1831
1832         spin_lock_init(&ci->lock);
1833
1834         ci->gadget.ops          = &usb_gadget_ops;
1835         ci->gadget.speed        = USB_SPEED_UNKNOWN;
1836         ci->gadget.max_speed    = USB_SPEED_HIGH;
1837         ci->gadget.is_otg       = ci->is_otg ? 1 : 0;
1838         ci->gadget.name         = ci->platdata->name;
1839
1840         INIT_LIST_HEAD(&ci->gadget.ep_list);
1841
1842         /* alloc resources */
1843         ci->qh_pool = dma_pool_create("ci_hw_qh", dev,
1844                                        sizeof(struct ci_hw_qh),
1845                                        64, CI_HDRC_PAGE_SIZE);
1846         if (ci->qh_pool == NULL)
1847                 return -ENOMEM;
1848
1849         ci->td_pool = dma_pool_create("ci_hw_td", dev,
1850                                        sizeof(struct ci_hw_td),
1851                                        64, CI_HDRC_PAGE_SIZE);
1852         if (ci->td_pool == NULL) {
1853                 retval = -ENOMEM;
1854                 goto free_qh_pool;
1855         }
1856
1857         retval = init_eps(ci);
1858         if (retval)
1859                 goto free_pools;
1860
1861         ci->gadget.ep0 = &ci->ep0in->ep;
1862
1863         retval = usb_add_gadget_udc(dev, &ci->gadget);
1864         if (retval)
1865                 goto destroy_eps;
1866
1867         pm_runtime_no_callbacks(&ci->gadget.dev);
1868         pm_runtime_enable(&ci->gadget.dev);
1869
1870         return retval;
1871
1872 destroy_eps:
1873         destroy_eps(ci);
1874 free_pools:
1875         dma_pool_destroy(ci->td_pool);
1876 free_qh_pool:
1877         dma_pool_destroy(ci->qh_pool);
1878         return retval;
1879 }
1880
1881 /**
1882  * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
1883  *
1884  * No interrupts active, the IRQ has been released
1885  */
1886 void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
1887 {
1888         if (!ci->roles[CI_ROLE_GADGET])
1889                 return;
1890
1891         usb_del_gadget_udc(&ci->gadget);
1892
1893         destroy_eps(ci);
1894
1895         dma_pool_destroy(ci->td_pool);
1896         dma_pool_destroy(ci->qh_pool);
1897 }
1898
1899 static int udc_id_switch_for_device(struct ci_hdrc *ci)
1900 {
1901         if (ci->is_otg)
1902                 /* Clear and enable BSV irq */
1903                 hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
1904                                         OTGSC_BSVIS | OTGSC_BSVIE);
1905
1906         return 0;
1907 }
1908
1909 static void udc_id_switch_for_host(struct ci_hdrc *ci)
1910 {
1911         /*
1912          * host doesn't care B_SESSION_VALID event
1913          * so clear and disbale BSV irq
1914          */
1915         if (ci->is_otg)
1916                 hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
1917 }
1918
1919 /**
1920  * ci_hdrc_gadget_init - initialize device related bits
1921  * ci: the controller
1922  *
1923  * This function initializes the gadget, if the device is "device capable".
1924  */
1925 int ci_hdrc_gadget_init(struct ci_hdrc *ci)
1926 {
1927         struct ci_role_driver *rdrv;
1928
1929         if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
1930                 return -ENXIO;
1931
1932         rdrv = devm_kzalloc(ci->dev, sizeof(struct ci_role_driver), GFP_KERNEL);
1933         if (!rdrv)
1934                 return -ENOMEM;
1935
1936         rdrv->start     = udc_id_switch_for_device;
1937         rdrv->stop      = udc_id_switch_for_host;
1938         rdrv->irq       = udc_irq;
1939         rdrv->name      = "gadget";
1940         ci->roles[CI_ROLE_GADGET] = rdrv;
1941
1942         return udc_start(ci);
1943 }