drivers/usb/dwc3/gadget.c

   1 /**
   2  * gadget.c - DesignWare USB3 DRD Controller Gadget Framework Link
   3  *
   4  * Copyright (C) 2010-2011 Texas Instruments Incorporated - http://www.ti.com
   5  *
   6  * Authors: Felipe Balbi <balbi@ti.com>,
   7  *          Sebastian Andrzej Siewior <bigeasy@linutronix.de>
   8  *
   9  * This program is free software: you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2  of
  11  * the License as published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  */
  18
  19 #include <linux/kernel.h>
  20 #include <linux/delay.h>
  21 #include <linux/slab.h>
  22 #include <linux/spinlock.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/pm_runtime.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/io.h>
  27 #include <linux/list.h>
  28 #include <linux/dma-mapping.h>
  29
  30 #include <linux/usb/ch9.h>
  31 #include <linux/usb/gadget.h>
  32
  33 #include "debug.h"
  34 #include "core.h"
  35 #include "gadget.h"
  36 #include "io.h"
  37
  38 /**
  39  * dwc3_gadget_set_test_mode - Enables USB2 Test Modes
  40  * @dwc: pointer to our context structure
  41  * @mode: the mode to set (J, K SE0 NAK, Force Enable)
  42  *
  43  * Caller should take care of locking. This function will
  44  * return 0 on success or -EINVAL if wrong Test Selector
  45  * is passed
  46  */
  47 int dwc3_gadget_set_test_mode(struct dwc3 *dwc, int mode)
  48 {
  49         u32             reg;
  50
  51         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
  52         reg &= ~DWC3_DCTL_TSTCTRL_MASK;
  53
  54         switch (mode) {
  55         case TEST_J:
  56         case TEST_K:
  57         case TEST_SE0_NAK:
  58         case TEST_PACKET:
  59         case TEST_FORCE_EN:
  60                 reg |= mode << 1;
  61                 break;
  62         default:
  63                 return -EINVAL;
  64         }
  65
  66         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
  67
  68         return 0;
  69 }
  70
  71 /**
  72  * dwc3_gadget_get_link_state - Gets current state of USB Link
  73  * @dwc: pointer to our context structure
  74  *
  75  * Caller should take care of locking. This function will
  76  * return the link state on success (>= 0) or -ETIMEDOUT.
  77  */
  78 int dwc3_gadget_get_link_state(struct dwc3 *dwc)
  79 {
  80         u32             reg;
  81
  82         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
  83
  84         return DWC3_DSTS_USBLNKST(reg);
  85 }
  86
  87 /**
  88  * dwc3_gadget_set_link_state - Sets USB Link to a particular State
  89  * @dwc: pointer to our context structure
  90  * @state: the state to put link into
  91  *
  92  * Caller should take care of locking. This function will
  93  * return 0 on success or -ETIMEDOUT.
  94  */
  95 int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
  96 {
  97         int             retries = 10000;
  98         u32             reg;
  99
 100         /*
 101          * Wait until device controller is ready. Only applies to 1.94a and
 102          * later RTL.
 103          */
 104         if (dwc->revision >= DWC3_REVISION_194A) {
 105                 while (--retries) {
 106                         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
 107                         if (reg & DWC3_DSTS_DCNRD)
 108                                 udelay(5);
 109                         else
 110                                 break;
 111                 }
 112
 113                 if (retries <= 0)
 114                         return -ETIMEDOUT;
 115         }
 116
 117         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
 118         reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
 119
 120         /* set requested state */
 121         reg |= DWC3_DCTL_ULSTCHNGREQ(state);
 122         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
 123
 124         /*
 125          * The following code is racy when called from dwc3_gadget_wakeup,
 126          * and is not needed, at least on newer versions
 127          */
 128         if (dwc->revision >= DWC3_REVISION_194A)
 129                 return 0;
 130
 131         /* wait for a change in DSTS */
 132         retries = 10000;
 133         while (--retries) {
 134                 reg = dwc3_readl(dwc->regs, DWC3_DSTS);
 135
 136                 if (DWC3_DSTS_USBLNKST(reg) == state)
 137                         return 0;
 138
 139                 udelay(5);
 140         }
 141
 142         dwc3_trace(trace_dwc3_gadget,
 143                         "link state change request timed out");
 144
 145         return -ETIMEDOUT;
 146 }
 147
 148 /**
 149  * dwc3_ep_inc_trb() - Increment a TRB index.
 150  * @index - Pointer to the TRB index to increment.
 151  *
 152  * The index should never point to the link TRB. After incrementing,
 153  * if it is point to the link TRB, wrap around to the beginning. The
 154  * link TRB is always at the last TRB entry.
 155  */
 156 static void dwc3_ep_inc_trb(u8 *index)
 157 {
 158         (*index)++;
 159         if (*index == (DWC3_TRB_NUM - 1))
 160                 *index = 0;
 161 }
 162
 163 static void dwc3_ep_inc_enq(struct dwc3_ep *dep)
 164 {
 165         dwc3_ep_inc_trb(&dep->trb_enqueue);
 166 }
 167
 168 static void dwc3_ep_inc_deq(struct dwc3_ep *dep)
 169 {
 170         dwc3_ep_inc_trb(&dep->trb_dequeue);
 171 }
 172
 173 void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
 174                 int status)
 175 {
 176         struct dwc3                     *dwc = dep->dwc;
 177         int                             i;
 178
 179         if (req->started) {
 180                 i = 0;
 181                 do {
 182                         dwc3_ep_inc_deq(dep);
 183                 } while(++i < req->request.num_mapped_sgs);
 184                 req->started = false;
 185         }
 186         list_del(&req->list);
 187         req->trb = NULL;
 188
 189         if (req->request.status == -EINPROGRESS)
 190                 req->request.status = status;
 191
 192         if (dwc->ep0_bounced && dep->number == 0)
 193                 dwc->ep0_bounced = false;
 194         else
 195                 usb_gadget_unmap_request(&dwc->gadget, &req->request,
 196                                 req->direction);
 197
 198         trace_dwc3_gadget_giveback(req);
 199
 200         spin_unlock(&dwc->lock);
 201         usb_gadget_giveback_request(&dep->endpoint, &req->request);
 202         spin_lock(&dwc->lock);
 203
 204         if (dep->number > 1)
 205                 pm_runtime_put(dwc->dev);
 206 }
 207
 208 int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned cmd, u32 param)
 209 {
 210         u32             timeout = 500;
 211         int             status = 0;
 212         int             ret = 0;
 213         u32             reg;
 214
 215         dwc3_writel(dwc->regs, DWC3_DGCMDPAR, param);
 216         dwc3_writel(dwc->regs, DWC3_DGCMD, cmd | DWC3_DGCMD_CMDACT);
 217
 218         do {
 219                 reg = dwc3_readl(dwc->regs, DWC3_DGCMD);
 220                 if (!(reg & DWC3_DGCMD_CMDACT)) {
 221                         status = DWC3_DGCMD_STATUS(reg);
 222                         if (status)
 223                                 ret = -EINVAL;
 224                         break;
 225                 }
 226         } while (timeout--);
 227
 228         if (!timeout) {
 229                 ret = -ETIMEDOUT;
 230                 status = -ETIMEDOUT;
 231         }
 232
 233         trace_dwc3_gadget_generic_cmd(cmd, param, status);
 234
 235         return ret;
 236 }
 237
 238 static int __dwc3_gadget_wakeup(struct dwc3 *dwc);
 239
 240 int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned cmd,
 241                 struct dwc3_gadget_ep_cmd_params *params)
 242 {
 243         struct dwc3             *dwc = dep->dwc;
 244         u32                     timeout = 500;
 245         u32                     reg;
 246
 247         int                     cmd_status = 0;
 248         int                     susphy = false;
 249         int                     ret = -EINVAL;
 250
 251         /*
 252          * Synopsys Databook 2.60a states, on section 6.3.2.5.[1-8], that if
 253          * we're issuing an endpoint command, we must check if
 254          * GUSB2PHYCFG.SUSPHY bit is set. If it is, then we need to clear it.
 255          *
 256          * We will also set SUSPHY bit to what it was before returning as stated
 257          * by the same section on Synopsys databook.
 258          */
 259         if (dwc->gadget.speed <= USB_SPEED_HIGH) {
 260                 reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
 261                 if (unlikely(reg & DWC3_GUSB2PHYCFG_SUSPHY)) {
 262                         susphy = true;
 263                         reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
 264                         dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
 265                 }
 266         }
 267
 268         if (cmd == DWC3_DEPCMD_STARTTRANSFER) {
 269                 int             needs_wakeup;
 270
 271                 needs_wakeup = (dwc->link_state == DWC3_LINK_STATE_U1 ||
 272                                 dwc->link_state == DWC3_LINK_STATE_U2 ||
 273                                 dwc->link_state == DWC3_LINK_STATE_U3);
 274
 275                 if (unlikely(needs_wakeup)) {
 276                         ret = __dwc3_gadget_wakeup(dwc);
 277                         dev_WARN_ONCE(dwc->dev, ret, "wakeup failed --> %d\n",
 278                                         ret);
 279                 }
 280         }
 281
 282         dwc3_writel(dep->regs, DWC3_DEPCMDPAR0, params->param0);
 283         dwc3_writel(dep->regs, DWC3_DEPCMDPAR1, params->param1);
 284         dwc3_writel(dep->regs, DWC3_DEPCMDPAR2, params->param2);
 285
 286         dwc3_writel(dep->regs, DWC3_DEPCMD, cmd | DWC3_DEPCMD_CMDACT);
 287         do {
 288                 reg = dwc3_readl(dep->regs, DWC3_DEPCMD);
 289                 if (!(reg & DWC3_DEPCMD_CMDACT)) {
 290                         cmd_status = DWC3_DEPCMD_STATUS(reg);
 291
 292                         switch (cmd_status) {
 293                         case 0:
 294                                 ret = 0;
 295                                 break;
 296                         case DEPEVT_TRANSFER_NO_RESOURCE:
 297                                 ret = -EINVAL;
 298                                 break;
 299                         case DEPEVT_TRANSFER_BUS_EXPIRY:
 300                                 /*
 301                                  * SW issues START TRANSFER command to
 302                                  * isochronous ep with future frame interval. If
 303                                  * future interval time has already passed when
 304                                  * core receives the command, it will respond
 305                                  * with an error status of 'Bus Expiry'.
 306                                  *
 307                                  * Instead of always returning -EINVAL, let's
 308                                  * give a hint to the gadget driver that this is
 309                                  * the case by returning -EAGAIN.
 310                                  */
 311                                 ret = -EAGAIN;
 312                                 break;
 313                         default:
 314                                 dev_WARN(dwc->dev, "UNKNOWN cmd status\n");
 315                         }
 316
 317                         break;
 318                 }
 319         } while (--timeout);
 320
 321         if (timeout == 0) {
 322                 ret = -ETIMEDOUT;
 323                 cmd_status = -ETIMEDOUT;
 324         }
 325
 326         trace_dwc3_gadget_ep_cmd(dep, cmd, params, cmd_status);
 327
 328         if (unlikely(susphy)) {
 329                 reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
 330                 reg |= DWC3_GUSB2PHYCFG_SUSPHY;
 331                 dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
 332         }
 333
 334         return ret;
 335 }
 336
 337 static int dwc3_send_clear_stall_ep_cmd(struct dwc3_ep *dep)
 338 {
 339         struct dwc3 *dwc = dep->dwc;
 340         struct dwc3_gadget_ep_cmd_params params;
 341         u32 cmd = DWC3_DEPCMD_CLEARSTALL;
 342
 343         /*
 344          * As of core revision 2.60a the recommended programming model
 345          * is to set the ClearPendIN bit when issuing a Clear Stall EP
 346          * command for IN endpoints. This is to prevent an issue where
 347          * some (non-compliant) hosts may not send ACK TPs for pending
 348          * IN transfers due to a mishandled error condition. Synopsys
 349          * STAR 9000614252.
 350          */
 351         if (dep->direction && (dwc->revision >= DWC3_REVISION_260A))
 352                 cmd |= DWC3_DEPCMD_CLEARPENDIN;
 353
 354         memset(&params, 0, sizeof(params));
 355
 356         return dwc3_send_gadget_ep_cmd(dep, cmd, &params);
 357 }
 358
 359 static dma_addr_t dwc3_trb_dma_offset(struct dwc3_ep *dep,
 360                 struct dwc3_trb *trb)
 361 {
 362         u32             offset = (char *) trb - (char *) dep->trb_pool;
 363
 364         return dep->trb_pool_dma + offset;
 365 }
 366
 367 static int dwc3_alloc_trb_pool(struct dwc3_ep *dep)
 368 {
 369         struct dwc3             *dwc = dep->dwc;
 370
 371         if (dep->trb_pool)
 372                 return 0;
 373
 374         dep->trb_pool = dma_alloc_coherent(dwc->dev,
 375                         sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
 376                         &dep->trb_pool_dma, GFP_KERNEL);
 377         if (!dep->trb_pool) {
 378                 dev_err(dep->dwc->dev, "failed to allocate trb pool for %s\n",
 379                                 dep->name);
 380                 return -ENOMEM;
 381         }
 382
 383         return 0;
 384 }
 385
 386 static void dwc3_free_trb_pool(struct dwc3_ep *dep)
 387 {
 388         struct dwc3             *dwc = dep->dwc;
 389
 390         dma_free_coherent(dwc->dev, sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
 391                         dep->trb_pool, dep->trb_pool_dma);
 392
 393         dep->trb_pool = NULL;
 394         dep->trb_pool_dma = 0;
 395 }
 396
 397 static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep);
 398
 399 /**
 400  * dwc3_gadget_start_config - Configure EP resources
 401  * @dwc: pointer to our controller context structure
 402  * @dep: endpoint that is being enabled
 403  *
 404  * The assignment of transfer resources cannot perfectly follow the
 405  * data book due to the fact that the controller driver does not have
 406  * all knowledge of the configuration in advance. It is given this
 407  * information piecemeal by the composite gadget framework after every
 408  * SET_CONFIGURATION and SET_INTERFACE. Trying to follow the databook
 409  * programming model in this scenario can cause errors. For two
 410  * reasons:
 411  *
 412  * 1) The databook says to do DEPSTARTCFG for every SET_CONFIGURATION
 413  * and SET_INTERFACE (8.1.5). This is incorrect in the scenario of
 414  * multiple interfaces.
 415  *
 416  * 2) The databook does not mention doing more DEPXFERCFG for new
 417  * endpoint on alt setting (8.1.6).
 418  *
 419  * The following simplified method is used instead:
 420  *
 421  * All hardware endpoints can be assigned a transfer resource and this
 422  * setting will stay persistent until either a core reset or
 423  * hibernation. So whenever we do a DEPSTARTCFG(0) we can go ahead and
 424  * do DEPXFERCFG for every hardware endpoint as well. We are
 425  * guaranteed that there are as many transfer resources as endpoints.
 426  *
 427  * This function is called for each endpoint when it is being enabled
 428  * but is triggered only when called for EP0-out, which always happens
 429  * first, and which should only happen in one of the above conditions.
 430  */
 431 static int dwc3_gadget_start_config(struct dwc3 *dwc, struct dwc3_ep *dep)
 432 {
 433         struct dwc3_gadget_ep_cmd_params params;
 434         u32                     cmd;
 435         int                     i;
 436         int                     ret;
 437
 438         if (dep->number)
 439                 return 0;
 440
 441         memset(&params, 0x00, sizeof(params));
 442         cmd = DWC3_DEPCMD_DEPSTARTCFG;
 443
 444         ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
 445         if (ret)
 446                 return ret;
 447
 448         for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
 449                 struct dwc3_ep *dep = dwc->eps[i];
 450
 451                 if (!dep)
 452                         continue;
 453
 454                 ret = dwc3_gadget_set_xfer_resource(dwc, dep);
 455                 if (ret)
 456                         return ret;
 457         }
 458
 459         return 0;
 460 }
 461
 462 static int dwc3_gadget_set_ep_config(struct dwc3 *dwc, struct dwc3_ep *dep,
 463                 const struct usb_endpoint_descriptor *desc,
 464                 const struct usb_ss_ep_comp_descriptor *comp_desc,
 465                 bool modify, bool restore)
 466 {
 467         struct dwc3_gadget_ep_cmd_params params;
 468
 469         if (dev_WARN_ONCE(dwc->dev, modify && restore,
 470                                         "Can't modify and restore\n"))
 471                 return -EINVAL;
 472
 473         memset(&params, 0x00, sizeof(params));
 474
 475         params.param0 = DWC3_DEPCFG_EP_TYPE(usb_endpoint_type(desc))
 476                 | DWC3_DEPCFG_MAX_PACKET_SIZE(usb_endpoint_maxp(desc));
 477
 478         /* Burst size is only needed in SuperSpeed mode */
 479         if (dwc->gadget.speed >= USB_SPEED_SUPER) {
 480                 u32 burst = dep->endpoint.maxburst;
 481                 params.param0 |= DWC3_DEPCFG_BURST_SIZE(burst - 1);
 482         }
 483
 484         if (modify) {
 485                 params.param0 |= DWC3_DEPCFG_ACTION_MODIFY;
 486         } else if (restore) {
 487                 params.param0 |= DWC3_DEPCFG_ACTION_RESTORE;
 488                 params.param2 |= dep->saved_state;
 489         } else {
 490                 params.param0 |= DWC3_DEPCFG_ACTION_INIT;
 491         }
 492
 493         params.param1 = DWC3_DEPCFG_XFER_COMPLETE_EN;
 494
 495         if (dep->number <= 1 || usb_endpoint_xfer_isoc(desc))
 496                 params.param1 |= DWC3_DEPCFG_XFER_NOT_READY_EN;
 497
 498         if (usb_ss_max_streams(comp_desc) && usb_endpoint_xfer_bulk(desc)) {
 499                 params.param1 |= DWC3_DEPCFG_STREAM_CAPABLE
 500                         | DWC3_DEPCFG_STREAM_EVENT_EN;
 501                 dep->stream_capable = true;
 502         }
 503
 504         if (!usb_endpoint_xfer_control(desc))
 505                 params.param1 |= DWC3_DEPCFG_XFER_IN_PROGRESS_EN;
 506
 507         /*
 508          * We are doing 1:1 mapping for endpoints, meaning
 509          * Physical Endpoints 2 maps to Logical Endpoint 2 and
 510          * so on. We consider the direction bit as part of the physical
 511          * endpoint number. So USB endpoint 0x81 is 0x03.
 512          */
 513         params.param1 |= DWC3_DEPCFG_EP_NUMBER(dep->number);
 514
 515         /*
 516          * We must use the lower 16 TX FIFOs even though
 517          * HW might have more
 518          */
 519         if (dep->direction)
 520                 params.param0 |= DWC3_DEPCFG_FIFO_NUMBER(dep->number >> 1);
 521
 522         if (desc->bInterval) {
 523                 params.param1 |= DWC3_DEPCFG_BINTERVAL_M1(desc->bInterval - 1);
 524                 dep->interval = 1 << (desc->bInterval - 1);
 525         }
 526
 527         return dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETEPCONFIG, &params);
 528 }
 529
 530 static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep)
 531 {
 532         struct dwc3_gadget_ep_cmd_params params;
 533
 534         memset(&params, 0x00, sizeof(params));
 535
 536         params.param0 = DWC3_DEPXFERCFG_NUM_XFER_RES(1);
 537
 538         return dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETTRANSFRESOURCE,
 539                         &params);
 540 }
 541
 542 /**
 543  * __dwc3_gadget_ep_enable - Initializes a HW endpoint
 544  * @dep: endpoint to be initialized
 545  * @desc: USB Endpoint Descriptor
 546  *
 547  * Caller should take care of locking
 548  */
 549 static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep,
 550                 const struct usb_endpoint_descriptor *desc,
 551                 const struct usb_ss_ep_comp_descriptor *comp_desc,
 552                 bool modify, bool restore)
 553 {
 554         struct dwc3             *dwc = dep->dwc;
 555         u32                     reg;
 556         int                     ret;
 557
 558         dwc3_trace(trace_dwc3_gadget, "Enabling %s", dep->name);
 559
 560         if (!(dep->flags & DWC3_EP_ENABLED)) {
 561                 ret = dwc3_gadget_start_config(dwc, dep);
 562                 if (ret)
 563                         return ret;
 564         }
 565
 566         ret = dwc3_gadget_set_ep_config(dwc, dep, desc, comp_desc, modify,
 567                         restore);
 568         if (ret)
 569                 return ret;
 570
 571         if (!(dep->flags & DWC3_EP_ENABLED)) {
 572                 struct dwc3_trb *trb_st_hw;
 573                 struct dwc3_trb *trb_link;
 574
 575                 dep->endpoint.desc = desc;
 576                 dep->comp_desc = comp_desc;
 577                 dep->type = usb_endpoint_type(desc);
 578                 dep->flags |= DWC3_EP_ENABLED;
 579
 580                 reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
 581                 reg |= DWC3_DALEPENA_EP(dep->number);
 582                 dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
 583
 584                 if (usb_endpoint_xfer_control(desc))
 585                         return 0;
 586
 587                 /* Initialize the TRB ring */
 588                 dep->trb_dequeue = 0;
 589                 dep->trb_enqueue = 0;
 590                 memset(dep->trb_pool, 0,
 591                        sizeof(struct dwc3_trb) * DWC3_TRB_NUM);
 592
 593                 /* Link TRB. The HWO bit is never reset */
 594                 trb_st_hw = &dep->trb_pool[0];
 595
 596                 trb_link = &dep->trb_pool[DWC3_TRB_NUM - 1];
 597                 trb_link->bpl = lower_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
 598                 trb_link->bph = upper_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
 599                 trb_link->ctrl |= DWC3_TRBCTL_LINK_TRB;
 600                 trb_link->ctrl |= DWC3_TRB_CTRL_HWO;
 601         }
 602
 603         return 0;
 604 }
 605
 606 static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force);
 607 static void dwc3_remove_requests(struct dwc3 *dwc, struct dwc3_ep *dep)
 608 {
 609         struct dwc3_request             *req;
 610
 611         dwc3_stop_active_transfer(dwc, dep->number, true);
 612
 613         /* - giveback all requests to gadget driver */
 614         while (!list_empty(&dep->started_list)) {
 615                 req = next_request(&dep->started_list);
 616
 617                 dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
 618         }
 619
 620         while (!list_empty(&dep->pending_list)) {
 621                 req = next_request(&dep->pending_list);
 622
 623                 dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
 624         }
 625 }
 626
 627 /**
 628  * __dwc3_gadget_ep_disable - Disables a HW endpoint
 629  * @dep: the endpoint to disable
 630  *
 631  * This function also removes requests which are currently processed ny the
 632  * hardware and those which are not yet scheduled.
 633  * Caller should take care of locking.
 634  */
 635 static int __dwc3_gadget_ep_disable(struct dwc3_ep *dep)
 636 {
 637         struct dwc3             *dwc = dep->dwc;
 638         u32                     reg;
 639
 640         dwc3_trace(trace_dwc3_gadget, "Disabling %s", dep->name);
 641
 642         dwc3_remove_requests(dwc, dep);
 643
 644         /* make sure HW endpoint isn't stalled */
 645         if (dep->flags & DWC3_EP_STALL)
 646                 __dwc3_gadget_ep_set_halt(dep, 0, false);
 647
 648         reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
 649         reg &= ~DWC3_DALEPENA_EP(dep->number);
 650         dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
 651
 652         dep->stream_capable = false;
 653         dep->endpoint.desc = NULL;
 654         dep->comp_desc = NULL;
 655         dep->type = 0;
 656         dep->flags = 0;
 657
 658         return 0;
 659 }
 660
 661 /* -------------------------------------------------------------------------- */
 662
 663 static int dwc3_gadget_ep0_enable(struct usb_ep *ep,
 664                 const struct usb_endpoint_descriptor *desc)
 665 {
 666         return -EINVAL;
 667 }
 668
 669 static int dwc3_gadget_ep0_disable(struct usb_ep *ep)
 670 {
 671         return -EINVAL;
 672 }
 673
 674 /* -------------------------------------------------------------------------- */
 675
 676 static int dwc3_gadget_ep_enable(struct usb_ep *ep,
 677                 const struct usb_endpoint_descriptor *desc)
 678 {
 679         struct dwc3_ep                  *dep;
 680         struct dwc3                     *dwc;
 681         unsigned long                   flags;
 682         int                             ret;
 683
 684         if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
 685                 pr_debug("dwc3: invalid parameters\n");
 686                 return -EINVAL;
 687         }
 688
 689         if (!desc->wMaxPacketSize) {
 690                 pr_debug("dwc3: missing wMaxPacketSize\n");
 691                 return -EINVAL;
 692         }
 693
 694         dep = to_dwc3_ep(ep);
 695         dwc = dep->dwc;
 696
 697         if (dev_WARN_ONCE(dwc->dev, dep->flags & DWC3_EP_ENABLED,
 698                                         "%s is already enabled\n",
 699                                         dep->name))
 700                 return 0;
 701
 702         spin_lock_irqsave(&dwc->lock, flags);
 703         ret = __dwc3_gadget_ep_enable(dep, desc, ep->comp_desc, false, false);
 704         spin_unlock_irqrestore(&dwc->lock, flags);
 705
 706         return ret;
 707 }
 708
 709 static int dwc3_gadget_ep_disable(struct usb_ep *ep)
 710 {
 711         struct dwc3_ep                  *dep;
 712         struct dwc3                     *dwc;
 713         unsigned long                   flags;
 714         int                             ret;
 715
 716         if (!ep) {
 717                 pr_debug("dwc3: invalid parameters\n");
 718                 return -EINVAL;
 719         }
 720
 721         dep = to_dwc3_ep(ep);
 722         dwc = dep->dwc;
 723
 724         if (dev_WARN_ONCE(dwc->dev, !(dep->flags & DWC3_EP_ENABLED),
 725                                         "%s is already disabled\n",
 726                                         dep->name))
 727                 return 0;
 728
 729         spin_lock_irqsave(&dwc->lock, flags);
 730         ret = __dwc3_gadget_ep_disable(dep);
 731         spin_unlock_irqrestore(&dwc->lock, flags);
 732
 733         return ret;
 734 }
 735
 736 static struct usb_request *dwc3_gadget_ep_alloc_request(struct usb_ep *ep,
 737         gfp_t gfp_flags)
 738 {
 739         struct dwc3_request             *req;
 740         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
 741
 742         req = kzalloc(sizeof(*req), gfp_flags);
 743         if (!req)
 744                 return NULL;
 745
 746         req->epnum      = dep->number;
 747         req->dep        = dep;
 748
 749         dep->allocated_requests++;
 750
 751         trace_dwc3_alloc_request(req);
 752
 753         return &req->request;
 754 }
 755
 756 static void dwc3_gadget_ep_free_request(struct usb_ep *ep,
 757                 struct usb_request *request)
 758 {
 759         struct dwc3_request             *req = to_dwc3_request(request);
 760         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
 761
 762         dep->allocated_requests--;
 763         trace_dwc3_free_request(req);
 764         kfree(req);
 765 }
 766
 767 /**
 768  * dwc3_prepare_one_trb - setup one TRB from one request
 769  * @dep: endpoint for which this request is prepared
 770  * @req: dwc3_request pointer
 771  */
 772 static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
 773                 struct dwc3_request *req, dma_addr_t dma,
 774                 unsigned length, unsigned last, unsigned chain, unsigned node)
 775 {
 776         struct dwc3_trb         *trb;
 777
 778         dwc3_trace(trace_dwc3_gadget, "%s: req %p dma %08llx length %d%s%s",
 779                         dep->name, req, (unsigned long long) dma,
 780                         length, last ? " last" : "",
 781                         chain ? " chain" : "");
 782
 783
 784         trb = &dep->trb_pool[dep->trb_enqueue];
 785
 786         if (!req->trb) {
 787                 dwc3_gadget_move_started_request(req);
 788                 req->trb = trb;
 789                 req->trb_dma = dwc3_trb_dma_offset(dep, trb);
 790                 req->first_trb_index = dep->trb_enqueue;
 791         }
 792
 793         dwc3_ep_inc_enq(dep);
 794
 795         trb->size = DWC3_TRB_SIZE_LENGTH(length);
 796         trb->bpl = lower_32_bits(dma);
 797         trb->bph = upper_32_bits(dma);
 798
 799         switch (usb_endpoint_type(dep->endpoint.desc)) {
 800         case USB_ENDPOINT_XFER_CONTROL:
 801                 trb->ctrl = DWC3_TRBCTL_CONTROL_SETUP;
 802                 break;
 803
 804         case USB_ENDPOINT_XFER_ISOC:
 805                 if (!node)
 806                         trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;
 807                 else
 808                         trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS;
 809
 810                 /* always enable Interrupt on Missed ISOC */
 811                 trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
 812                 break;
 813
 814         case USB_ENDPOINT_XFER_BULK:
 815         case USB_ENDPOINT_XFER_INT:
 816                 trb->ctrl = DWC3_TRBCTL_NORMAL;
 817                 break;
 818         default:
 819                 /*
 820                  * This is only possible with faulty memory because we
 821                  * checked it already :)
 822                  */
 823                 BUG();
 824         }
 825
 826         /* always enable Continue on Short Packet */
 827         trb->ctrl |= DWC3_TRB_CTRL_CSP;
 828
 829         if (!req->request.no_interrupt && !chain)
 830                 trb->ctrl |= DWC3_TRB_CTRL_IOC | DWC3_TRB_CTRL_ISP_IMI;
 831
 832         if (last)
 833                 trb->ctrl |= DWC3_TRB_CTRL_LST;
 834
 835         if (chain)
 836                 trb->ctrl |= DWC3_TRB_CTRL_CHN;
 837
 838         if (usb_endpoint_xfer_bulk(dep->endpoint.desc) && dep->stream_capable)
 839                 trb->ctrl |= DWC3_TRB_CTRL_SID_SOFN(req->request.stream_id);
 840
 841         trb->ctrl |= DWC3_TRB_CTRL_HWO;
 842
 843         dep->queued_requests++;
 844
 845         trace_dwc3_prepare_trb(dep, trb);
 846 }
 847
 848 /**
 849  * dwc3_ep_prev_trb() - Returns the previous TRB in the ring
 850  * @dep: The endpoint with the TRB ring
 851  * @index: The index of the current TRB in the ring
 852  *
 853  * Returns the TRB prior to the one pointed to by the index. If the
 854  * index is 0, we will wrap backwards, skip the link TRB, and return
 855  * the one just before that.
 856  */
 857 static struct dwc3_trb *dwc3_ep_prev_trb(struct dwc3_ep *dep, u8 index)
 858 {
 859         if (!index)
 860                 index = DWC3_TRB_NUM - 2;
 861         else
 862                 index = dep->trb_enqueue - 1;
 863
 864         return &dep->trb_pool[index];
 865 }
 866
 867 static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep)
 868 {
 869         struct dwc3_trb         *tmp;
 870         u8                      trbs_left;
 871
 872         /*
 873          * If enqueue & dequeue are equal than it is either full or empty.
 874          *
 875          * One way to know for sure is if the TRB right before us has HWO bit
 876          * set or not. If it has, then we're definitely full and can't fit any
 877          * more transfers in our ring.
 878          */
 879         if (dep->trb_enqueue == dep->trb_dequeue) {
 880                 tmp = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
 881                 if (tmp->ctrl & DWC3_TRB_CTRL_HWO)
 882                         return 0;
 883
 884                 return DWC3_TRB_NUM - 1;
 885         }
 886
 887         trbs_left = dep->trb_dequeue - dep->trb_enqueue;
 888         trbs_left &= (DWC3_TRB_NUM - 1);
 889
 890         if (dep->trb_dequeue < dep->trb_enqueue)
 891                 trbs_left--;
 892
 893         return trbs_left;
 894 }
 895
 896 static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
 897                 struct dwc3_request *req, unsigned int trbs_left,
 898                 unsigned int more_coming)
 899 {
 900         struct usb_request *request = &req->request;
 901         struct scatterlist *sg = request->sg;
 902         struct scatterlist *s;
 903         unsigned int    last = false;
 904         unsigned int    length;
 905         dma_addr_t      dma;
 906         int             i;
 907
 908         for_each_sg(sg, s, request->num_mapped_sgs, i) {
 909                 unsigned chain = true;
 910
 911                 length = sg_dma_len(s);
 912                 dma = sg_dma_address(s);
 913
 914                 if (sg_is_last(s)) {
 915                         if (usb_endpoint_xfer_int(dep->endpoint.desc) ||
 916                                 !more_coming)
 917                                 last = true;
 918
 919                         chain = false;
 920                 }
 921
 922                 if (!trbs_left--)
 923                         last = true;
 924
 925                 if (last)
 926                         chain = false;
 927
 928                 dwc3_prepare_one_trb(dep, req, dma, length,
 929                                 last, chain, i);
 930
 931                 if (last)
 932                         break;
 933         }
 934 }
 935
 936 static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
 937                 struct dwc3_request *req, unsigned int trbs_left,
 938                 unsigned int more_coming)
 939 {
 940         unsigned int    last = false;
 941         unsigned int    length;
 942         dma_addr_t      dma;
 943
 944         dma = req->request.dma;
 945         length = req->request.length;
 946
 947         if (!trbs_left)
 948                 last = true;
 949
 950         /* Is this the last request? */
 951         if (usb_endpoint_xfer_int(dep->endpoint.desc) || !more_coming)
 952                 last = true;
 953
 954         dwc3_prepare_one_trb(dep, req, dma, length,
 955                         last, false, 0);
 956 }
 957
 958 /*
 959  * dwc3_prepare_trbs - setup TRBs from requests
 960  * @dep: endpoint for which requests are being prepared
 961  *
 962  * The function goes through the requests list and sets up TRBs for the
 963  * transfers. The function returns once there are no more TRBs available or
 964  * it runs out of requests.
 965  */
 966 static void dwc3_prepare_trbs(struct dwc3_ep *dep)
 967 {
 968         struct dwc3_request     *req, *n;
 969         unsigned int            more_coming;
 970         u32                     trbs_left;
 971
 972         BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);
 973
 974         trbs_left = dwc3_calc_trbs_left(dep);
 975         if (!trbs_left)
 976                 return;
 977
 978         more_coming = dep->allocated_requests - dep->queued_requests;
 979
 980         list_for_each_entry_safe(req, n, &dep->pending_list, list) {
 981                 if (req->request.num_mapped_sgs > 0)
 982                         dwc3_prepare_one_trb_sg(dep, req, trbs_left--,
 983                                         more_coming);
 984                 else
 985                         dwc3_prepare_one_trb_linear(dep, req, trbs_left--,
 986                                         more_coming);
 987
 988                 if (!trbs_left)
 989                         return;
 990         }
 991 }
 992
 993 static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep, u16 cmd_param)
 994 {
 995         struct dwc3_gadget_ep_cmd_params params;
 996         struct dwc3_request             *req;
 997         struct dwc3                     *dwc = dep->dwc;
 998         int                             starting;
 999         int                             ret;
1000         u32                             cmd;
1001
1002         starting = !(dep->flags & DWC3_EP_BUSY);
1003
1004         dwc3_prepare_trbs(dep);
1005         req = next_request(&dep->started_list);
1006         if (!req) {
1007                 dep->flags |= DWC3_EP_PENDING_REQUEST;
1008                 return 0;
1009         }
1010
1011         memset(&params, 0, sizeof(params));
1012
1013         if (starting) {
1014                 params.param0 = upper_32_bits(req->trb_dma);
1015                 params.param1 = lower_32_bits(req->trb_dma);
1016                 cmd = DWC3_DEPCMD_STARTTRANSFER |
1017                         DWC3_DEPCMD_PARAM(cmd_param);
1018         } else {
1019                 cmd = DWC3_DEPCMD_UPDATETRANSFER |
1020                         DWC3_DEPCMD_PARAM(dep->resource_index);
1021         }
1022
1023         ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
1024         if (ret < 0) {
1025                 /*
1026                  * FIXME we need to iterate over the list of requests
1027                  * here and stop, unmap, free and del each of the linked
1028                  * requests instead of what we do now.
1029                  */
1030                 usb_gadget_unmap_request(&dwc->gadget, &req->request,
1031                                 req->direction);
1032                 list_del(&req->list);
1033                 return ret;
1034         }
1035
1036         dep->flags |= DWC3_EP_BUSY;
1037
1038         if (starting) {
1039                 dep->resource_index = dwc3_gadget_ep_get_transfer_index(dep);
1040                 WARN_ON_ONCE(!dep->resource_index);
1041         }
1042
1043         return 0;
1044 }
1045
1046 static void __dwc3_gadget_start_isoc(struct dwc3 *dwc,
1047                 struct dwc3_ep *dep, u32 cur_uf)
1048 {
1049         u32 uf;
1050
1051         if (list_empty(&dep->pending_list)) {
1052                 dwc3_trace(trace_dwc3_gadget,
1053                                 "ISOC ep %s run out for requests",
1054                                 dep->name);
1055                 dep->flags |= DWC3_EP_PENDING_REQUEST;
1056                 return;
1057         }
1058
1059         /* 4 micro frames in the future */
1060         uf = cur_uf + dep->interval * 4;
1061
1062         __dwc3_gadget_kick_transfer(dep, uf);
1063 }
1064
1065 static void dwc3_gadget_start_isoc(struct dwc3 *dwc,
1066                 struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
1067 {
1068         u32 cur_uf, mask;
1069
1070         mask = ~(dep->interval - 1);
1071         cur_uf = event->parameters & mask;
1072
1073         __dwc3_gadget_start_isoc(dwc, dep, cur_uf);
1074 }
1075
1076 static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
1077 {
1078         struct dwc3             *dwc = dep->dwc;
1079         int                     ret;
1080
1081         if (!dep->endpoint.desc) {
1082                 dwc3_trace(trace_dwc3_gadget,
1083                                 "trying to queue request %p to disabled %s",
1084                                 &req->request, dep->endpoint.name);
1085                 return -ESHUTDOWN;
1086         }
1087
1088         if (WARN(req->dep != dep, "request %p belongs to '%s'\n",
1089                                 &req->request, req->dep->name)) {
1090                 dwc3_trace(trace_dwc3_gadget, "request %p belongs to '%s'",
1091                                 &req->request, req->dep->name);
1092                 return -EINVAL;
1093         }
1094
1095         pm_runtime_get(dwc->dev);
1096
1097         req->request.actual     = 0;
1098         req->request.status     = -EINPROGRESS;
1099         req->direction          = dep->direction;
1100         req->epnum              = dep->number;
1101
1102         trace_dwc3_ep_queue(req);
1103
1104         /*
1105          * We only add to our list of requests now and
1106          * start consuming the list once we get XferNotReady
1107          * IRQ.
1108          *
1109          * That way, we avoid doing anything that we don't need
1110          * to do now and defer it until the point we receive a
1111          * particular token from the Host side.
1112          *
1113          * This will also avoid Host cancelling URBs due to too
1114          * many NAKs.
1115          */
1116         ret = usb_gadget_map_request(&dwc->gadget, &req->request,
1117                         dep->direction);
1118         if (ret)
1119                 return ret;
1120
1121         list_add_tail(&req->list, &dep->pending_list);
1122
1123         /*
1124          * If there are no pending requests and the endpoint isn't already
1125          * busy, we will just start the request straight away.
1126          *
1127          * This will save one IRQ (XFER_NOT_READY) and possibly make it a
1128          * little bit faster.
1129          */
1130         if (!usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
1131                         !usb_endpoint_xfer_int(dep->endpoint.desc)) {
1132                 ret = __dwc3_gadget_kick_transfer(dep, 0);
1133                 goto out;
1134         }
1135
1136         /*
1137          * There are a few special cases:
1138          *
1139          * 1. XferNotReady with empty list of requests. We need to kick the
1140          *    transfer here in that situation, otherwise we will be NAKing
1141          *    forever. If we get XferNotReady before gadget driver has a
1142          *    chance to queue a request, we will ACK the IRQ but won't be
1143          *    able to receive the data until the next request is queued.
1144          *    The following code is handling exactly that.
1145          *
1146          */
1147         if (dep->flags & DWC3_EP_PENDING_REQUEST) {
1148                 /*
1149                  * If xfernotready is already elapsed and it is a case
1150                  * of isoc transfer, then issue END TRANSFER, so that
1151                  * you can receive xfernotready again and can have
1152                  * notion of current microframe.
1153                  */
1154                 if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1155                         if (list_empty(&dep->started_list)) {
1156                                 dwc3_stop_active_transfer(dwc, dep->number, true);
1157                                 dep->flags = DWC3_EP_ENABLED;
1158                         }
1159                         return 0;
1160                 }
1161
1162                 ret = __dwc3_gadget_kick_transfer(dep, 0);
1163                 if (!ret)
1164                         dep->flags &= ~DWC3_EP_PENDING_REQUEST;
1165
1166                 goto out;
1167         }
1168
1169         /*
1170          * 2. XferInProgress on Isoc EP with an active transfer. We need to
1171          *    kick the transfer here after queuing a request, otherwise the
1172          *    core may not see the modified TRB(s).
1173          */
1174         if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
1175                         (dep->flags & DWC3_EP_BUSY) &&
1176                         !(dep->flags & DWC3_EP_MISSED_ISOC)) {
1177                 WARN_ON_ONCE(!dep->resource_index);
1178                 ret = __dwc3_gadget_kick_transfer(dep, dep->resource_index);
1179                 goto out;
1180         }
1181
1182         /*
1183          * 4. Stream Capable Bulk Endpoints. We need to start the transfer
1184          * right away, otherwise host will not know we have streams to be
1185          * handled.
1186          */
1187         if (dep->stream_capable)
1188                 ret = __dwc3_gadget_kick_transfer(dep, 0);
1189
1190 out:
1191         if (ret && ret != -EBUSY)
1192                 dwc3_trace(trace_dwc3_gadget,
1193                                 "%s: failed to kick transfers",
1194                                 dep->name);
1195         if (ret == -EBUSY)
1196                 ret = 0;
1197
1198         return ret;
1199 }
1200
1201 static void __dwc3_gadget_ep_zlp_complete(struct usb_ep *ep,
1202                 struct usb_request *request)
1203 {
1204         dwc3_gadget_ep_free_request(ep, request);
1205 }
1206
1207 static int __dwc3_gadget_ep_queue_zlp(struct dwc3 *dwc, struct dwc3_ep *dep)
1208 {
1209         struct dwc3_request             *req;
1210         struct usb_request              *request;
1211         struct usb_ep                   *ep = &dep->endpoint;
1212
1213         dwc3_trace(trace_dwc3_gadget, "queueing ZLP");
1214         request = dwc3_gadget_ep_alloc_request(ep, GFP_ATOMIC);
1215         if (!request)
1216                 return -ENOMEM;
1217
1218         request->length = 0;
1219         request->buf = dwc->zlp_buf;
1220         request->complete = __dwc3_gadget_ep_zlp_complete;
1221
1222         req = to_dwc3_request(request);
1223
1224         return __dwc3_gadget_ep_queue(dep, req);
1225 }
1226
1227 static int dwc3_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
1228         gfp_t gfp_flags)
1229 {
1230         struct dwc3_request             *req = to_dwc3_request(request);
1231         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1232         struct dwc3                     *dwc = dep->dwc;
1233
1234         unsigned long                   flags;
1235
1236         int                             ret;
1237
1238         spin_lock_irqsave(&dwc->lock, flags);
1239         ret = __dwc3_gadget_ep_queue(dep, req);
1240
1241         /*
1242          * Okay, here's the thing, if gadget driver has requested for a ZLP by
1243          * setting request->zero, instead of doing magic, we will just queue an
1244          * extra usb_request ourselves so that it gets handled the same way as
1245          * any other request.
1246          */
1247         if (ret == 0 && request->zero && request->length &&
1248             (request->length % ep->maxpacket == 0))
1249                 ret = __dwc3_gadget_ep_queue_zlp(dwc, dep);
1250
1251         spin_unlock_irqrestore(&dwc->lock, flags);
1252
1253         return ret;
1254 }
1255
1256 static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
1257                 struct usb_request *request)
1258 {
1259         struct dwc3_request             *req = to_dwc3_request(request);
1260         struct dwc3_request             *r = NULL;
1261
1262         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1263         struct dwc3                     *dwc = dep->dwc;
1264
1265         unsigned long                   flags;
1266         int                             ret = 0;
1267
1268         trace_dwc3_ep_dequeue(req);
1269
1270         spin_lock_irqsave(&dwc->lock, flags);
1271
1272         list_for_each_entry(r, &dep->pending_list, list) {
1273                 if (r == req)
1274                         break;
1275         }
1276
1277         if (r != req) {
1278                 list_for_each_entry(r, &dep->started_list, list) {
1279                         if (r == req)
1280                                 break;
1281                 }
1282                 if (r == req) {
1283                         /* wait until it is processed */
1284                         dwc3_stop_active_transfer(dwc, dep->number, true);
1285                         goto out1;
1286                 }
1287                 dev_err(dwc->dev, "request %p was not queued to %s\n",
1288                                 request, ep->name);
1289                 ret = -EINVAL;
1290                 goto out0;
1291         }
1292
1293 out1:
1294         /* giveback the request */
1295         dwc3_gadget_giveback(dep, req, -ECONNRESET);
1296
1297 out0:
1298         spin_unlock_irqrestore(&dwc->lock, flags);
1299
1300         return ret;
1301 }
1302
1303 int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
1304 {
1305         struct dwc3_gadget_ep_cmd_params        params;
1306         struct dwc3                             *dwc = dep->dwc;
1307         int                                     ret;
1308
1309         if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1310                 dev_err(dwc->dev, "%s is of Isochronous type\n", dep->name);
1311                 return -EINVAL;
1312         }
1313
1314         memset(&params, 0x00, sizeof(params));
1315
1316         if (value) {
1317                 struct dwc3_trb *trb;
1318
1319                 unsigned transfer_in_flight;
1320                 unsigned started;
1321
1322                 if (dep->number > 1)
1323                         trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
1324                 else
1325                         trb = &dwc->ep0_trb[dep->trb_enqueue];
1326
1327                 transfer_in_flight = trb->ctrl & DWC3_TRB_CTRL_HWO;
1328                 started = !list_empty(&dep->started_list);
1329
1330                 if (!protocol && ((dep->direction && transfer_in_flight) ||
1331                                 (!dep->direction && started))) {
1332                         dwc3_trace(trace_dwc3_gadget,
1333                                         "%s: pending request, cannot halt",
1334                                         dep->name);
1335                         return -EAGAIN;
1336                 }
1337
1338                 ret = dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETSTALL,
1339                                 &params);
1340                 if (ret)
1341                         dev_err(dwc->dev, "failed to set STALL on %s\n",
1342                                         dep->name);
1343                 else
1344                         dep->flags |= DWC3_EP_STALL;
1345         } else {
1346
1347                 ret = dwc3_send_clear_stall_ep_cmd(dep);
1348                 if (ret)
1349                         dev_err(dwc->dev, "failed to clear STALL on %s\n",
1350                                         dep->name);
1351                 else
1352                         dep->flags &= ~(DWC3_EP_STALL | DWC3_EP_WEDGE);
1353         }
1354
1355         return ret;
1356 }
1357
1358 static int dwc3_gadget_ep_set_halt(struct usb_ep *ep, int value)
1359 {
1360         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1361         struct dwc3                     *dwc = dep->dwc;
1362
1363         unsigned long                   flags;
1364
1365         int                             ret;
1366
1367         spin_lock_irqsave(&dwc->lock, flags);
1368         ret = __dwc3_gadget_ep_set_halt(dep, value, false);
1369         spin_unlock_irqrestore(&dwc->lock, flags);
1370
1371         return ret;
1372 }
1373
1374 static int dwc3_gadget_ep_set_wedge(struct usb_ep *ep)
1375 {
1376         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1377         struct dwc3                     *dwc = dep->dwc;
1378         unsigned long                   flags;
1379         int                             ret;
1380
1381         spin_lock_irqsave(&dwc->lock, flags);
1382         dep->flags |= DWC3_EP_WEDGE;
1383
1384         if (dep->number == 0 || dep->number == 1)
1385                 ret = __dwc3_gadget_ep0_set_halt(ep, 1);
1386         else
1387                 ret = __dwc3_gadget_ep_set_halt(dep, 1, false);
1388         spin_unlock_irqrestore(&dwc->lock, flags);
1389
1390         return ret;
1391 }
1392
1393 /* -------------------------------------------------------------------------- */
1394
1395 static struct usb_endpoint_descriptor dwc3_gadget_ep0_desc = {
1396         .bLength        = USB_DT_ENDPOINT_SIZE,
1397         .bDescriptorType = USB_DT_ENDPOINT,
1398         .bmAttributes   = USB_ENDPOINT_XFER_CONTROL,
1399 };
1400
1401 static const struct usb_ep_ops dwc3_gadget_ep0_ops = {
1402         .enable         = dwc3_gadget_ep0_enable,
1403         .disable        = dwc3_gadget_ep0_disable,
1404         .alloc_request  = dwc3_gadget_ep_alloc_request,
1405         .free_request   = dwc3_gadget_ep_free_request,
1406         .queue          = dwc3_gadget_ep0_queue,
1407         .dequeue        = dwc3_gadget_ep_dequeue,
1408         .set_halt       = dwc3_gadget_ep0_set_halt,
1409         .set_wedge      = dwc3_gadget_ep_set_wedge,
1410 };
1411
1412 static const struct usb_ep_ops dwc3_gadget_ep_ops = {
1413         .enable         = dwc3_gadget_ep_enable,
1414         .disable        = dwc3_gadget_ep_disable,
1415         .alloc_request  = dwc3_gadget_ep_alloc_request,
1416         .free_request   = dwc3_gadget_ep_free_request,
1417         .queue          = dwc3_gadget_ep_queue,
1418         .dequeue        = dwc3_gadget_ep_dequeue,
1419         .set_halt       = dwc3_gadget_ep_set_halt,
1420         .set_wedge      = dwc3_gadget_ep_set_wedge,
1421 };
1422
1423 /* -------------------------------------------------------------------------- */
1424
1425 static int dwc3_gadget_get_frame(struct usb_gadget *g)
1426 {
1427         struct dwc3             *dwc = gadget_to_dwc(g);
1428         u32                     reg;
1429
1430         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1431         return DWC3_DSTS_SOFFN(reg);
1432 }
1433
1434 static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
1435 {
1436         unsigned long           timeout;
1437
1438         int                     ret;
1439         u32                     reg;
1440
1441         u8                      link_state;
1442         u8                      speed;
1443
1444         /*
1445          * According to the Databook Remote wakeup request should
1446          * be issued only when the device is in early suspend state.
1447          *
1448          * We can check that via USB Link State bits in DSTS register.
1449          */
1450         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1451
1452         speed = reg & DWC3_DSTS_CONNECTSPD;
1453         if ((speed == DWC3_DSTS_SUPERSPEED) ||
1454             (speed == DWC3_DSTS_SUPERSPEED_PLUS)) {
1455                 dwc3_trace(trace_dwc3_gadget, "no wakeup on SuperSpeed");
1456                 return 0;
1457         }
1458
1459         link_state = DWC3_DSTS_USBLNKST(reg);
1460
1461         switch (link_state) {
1462         case DWC3_LINK_STATE_RX_DET:    /* in HS, means Early Suspend */
1463         case DWC3_LINK_STATE_U3:        /* in HS, means SUSPEND */
1464                 break;
1465         default:
1466                 dwc3_trace(trace_dwc3_gadget,
1467                                 "can't wakeup from '%s'",
1468                                 dwc3_gadget_link_string(link_state));
1469                 return -EINVAL;
1470         }
1471
1472         ret = dwc3_gadget_set_link_state(dwc, DWC3_LINK_STATE_RECOV);
1473         if (ret < 0) {
1474                 dev_err(dwc->dev, "failed to put link in Recovery\n");
1475                 return ret;
1476         }
1477
1478         /* Recent versions do this automatically */
1479         if (dwc->revision < DWC3_REVISION_194A) {
1480                 /* write zeroes to Link Change Request */
1481                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1482                 reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
1483                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1484         }
1485
1486         /* poll until Link State changes to ON */
1487         timeout = jiffies + msecs_to_jiffies(100);
1488
1489         while (!time_after(jiffies, timeout)) {
1490                 reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1491
1492                 /* in HS, means ON */
1493                 if (DWC3_DSTS_USBLNKST(reg) == DWC3_LINK_STATE_U0)
1494                         break;
1495         }
1496
1497         if (DWC3_DSTS_USBLNKST(reg) != DWC3_LINK_STATE_U0) {
1498                 dev_err(dwc->dev, "failed to send remote wakeup\n");
1499                 return -EINVAL;
1500         }
1501
1502         return 0;
1503 }
1504
1505 static int dwc3_gadget_wakeup(struct usb_gadget *g)
1506 {
1507         struct dwc3             *dwc = gadget_to_dwc(g);
1508         unsigned long           flags;
1509         int                     ret;
1510
1511         spin_lock_irqsave(&dwc->lock, flags);
1512         ret = __dwc3_gadget_wakeup(dwc);
1513         spin_unlock_irqrestore(&dwc->lock, flags);
1514
1515         return ret;
1516 }
1517
1518 static int dwc3_gadget_set_selfpowered(struct usb_gadget *g,
1519                 int is_selfpowered)
1520 {
1521         struct dwc3             *dwc = gadget_to_dwc(g);
1522         unsigned long           flags;
1523
1524         spin_lock_irqsave(&dwc->lock, flags);
1525         g->is_selfpowered = !!is_selfpowered;
1526         spin_unlock_irqrestore(&dwc->lock, flags);
1527
1528         return 0;
1529 }
1530
1531 static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
1532 {
1533         u32                     reg;
1534         u32                     timeout = 500;
1535
1536         if (pm_runtime_suspended(dwc->dev))
1537                 return 0;
1538
1539         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1540         if (is_on) {
1541                 if (dwc->revision <= DWC3_REVISION_187A) {
1542                         reg &= ~DWC3_DCTL_TRGTULST_MASK;
1543                         reg |= DWC3_DCTL_TRGTULST_RX_DET;
1544                 }
1545
1546                 if (dwc->revision >= DWC3_REVISION_194A)
1547                         reg &= ~DWC3_DCTL_KEEP_CONNECT;
1548                 reg |= DWC3_DCTL_RUN_STOP;
1549
1550                 if (dwc->has_hibernation)
1551                         reg |= DWC3_DCTL_KEEP_CONNECT;
1552
1553                 dwc->pullups_connected = true;
1554         } else {
1555                 reg &= ~DWC3_DCTL_RUN_STOP;
1556
1557                 if (dwc->has_hibernation && !suspend)
1558                         reg &= ~DWC3_DCTL_KEEP_CONNECT;
1559
1560                 dwc->pullups_connected = false;
1561         }
1562
1563         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1564
1565         do {
1566                 reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1567                 reg &= DWC3_DSTS_DEVCTRLHLT;
1568         } while (--timeout && !(!is_on ^ !reg));
1569
1570         if (!timeout)
1571                 return -ETIMEDOUT;
1572
1573         dwc3_trace(trace_dwc3_gadget, "gadget %s data soft-%s",
1574                         dwc->gadget_driver
1575                         ? dwc->gadget_driver->function : "no-function",
1576                         is_on ? "connect" : "disconnect");
1577
1578         return 0;
1579 }
1580
1581 static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
1582 {
1583         struct dwc3             *dwc = gadget_to_dwc(g);
1584         unsigned long           flags;
1585         int                     ret;
1586
1587         is_on = !!is_on;
1588
1589         spin_lock_irqsave(&dwc->lock, flags);
1590         ret = dwc3_gadget_run_stop(dwc, is_on, false);
1591         spin_unlock_irqrestore(&dwc->lock, flags);
1592
1593         return ret;
1594 }
1595
1596 static void dwc3_gadget_enable_irq(struct dwc3 *dwc)
1597 {
1598         u32                     reg;
1599
1600         /* Enable all but Start and End of Frame IRQs */
1601         reg = (DWC3_DEVTEN_VNDRDEVTSTRCVEDEN |
1602                         DWC3_DEVTEN_EVNTOVERFLOWEN |
1603                         DWC3_DEVTEN_CMDCMPLTEN |
1604                         DWC3_DEVTEN_ERRTICERREN |
1605                         DWC3_DEVTEN_WKUPEVTEN |
1606                         DWC3_DEVTEN_ULSTCNGEN |
1607                         DWC3_DEVTEN_CONNECTDONEEN |
1608                         DWC3_DEVTEN_USBRSTEN |
1609                         DWC3_DEVTEN_DISCONNEVTEN);
1610
1611         dwc3_writel(dwc->regs, DWC3_DEVTEN, reg);
1612 }
1613
1614 static void dwc3_gadget_disable_irq(struct dwc3 *dwc)
1615 {
1616         /* mask all interrupts */
1617         dwc3_writel(dwc->regs, DWC3_DEVTEN, 0x00);
1618 }
1619
1620 static irqreturn_t dwc3_interrupt(int irq, void *_dwc);
1621 static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc);
1622
1623 /**
1624  * dwc3_gadget_setup_nump - Calculate and initialize NUMP field of DCFG
1625  * dwc: pointer to our context structure
1626  *
1627  * The following looks like complex but it's actually very simple. In order to
1628  * calculate the number of packets we can burst at once on OUT transfers, we're
1629  * gonna use RxFIFO size.
1630  *
1631  * To calculate RxFIFO size we need two numbers:
1632  * MDWIDTH = size, in bits, of the internal memory bus
1633  * RAM2_DEPTH = depth, in MDWIDTH, of internal RAM2 (where RxFIFO sits)
1634  *
1635  * Given these two numbers, the formula is simple:
1636  *
1637  * RxFIFO Size = (RAM2_DEPTH * MDWIDTH / 8) - 24 - 16;
1638  *
1639  * 24 bytes is for 3x SETUP packets
1640  * 16 bytes is a clock domain crossing tolerance
1641  *
1642  * Given RxFIFO Size, NUMP = RxFIFOSize / 1024;
1643  */
1644 static void dwc3_gadget_setup_nump(struct dwc3 *dwc)
1645 {
1646         u32 ram2_depth;
1647         u32 mdwidth;
1648         u32 nump;
1649         u32 reg;
1650
1651         ram2_depth = DWC3_GHWPARAMS7_RAM2_DEPTH(dwc->hwparams.hwparams7);
1652         mdwidth = DWC3_GHWPARAMS0_MDWIDTH(dwc->hwparams.hwparams0);
1653
1654         nump = ((ram2_depth * mdwidth / 8) - 24 - 16) / 1024;
1655         nump = min_t(u32, nump, 16);
1656
1657         /* update NumP */
1658         reg = dwc3_readl(dwc->regs, DWC3_DCFG);
1659         reg &= ~DWC3_DCFG_NUMP_MASK;
1660         reg |= nump << DWC3_DCFG_NUMP_SHIFT;
1661         dwc3_writel(dwc->regs, DWC3_DCFG, reg);
1662 }
1663
1664 static int __dwc3_gadget_start(struct dwc3 *dwc)
1665 {
1666         struct dwc3_ep          *dep;
1667         int                     ret = 0;
1668         u32                     reg;
1669
1670         reg = dwc3_readl(dwc->regs, DWC3_DCFG);
1671         reg &= ~(DWC3_DCFG_SPEED_MASK);
1672
1673         /**
1674          * WORKAROUND: DWC3 revision < 2.20a have an issue
1675          * which would cause metastability state on Run/Stop
1676          * bit if we try to force the IP to USB2-only mode.
1677          *
1678          * Because of that, we cannot configure the IP to any
1679          * speed other than the SuperSpeed
1680          *
1681          * Refers to:
1682          *
1683          * STAR#9000525659: Clock Domain Crossing on DCTL in
1684          * USB 2.0 Mode
1685          */
1686         if (dwc->revision < DWC3_REVISION_220A) {
1687                 reg |= DWC3_DCFG_SUPERSPEED;
1688         } else {
1689                 switch (dwc->maximum_speed) {
1690                 case USB_SPEED_LOW:
1691                         reg |= DWC3_DCFG_LOWSPEED;
1692                         break;
1693                 case USB_SPEED_FULL:
1694                         reg |= DWC3_DCFG_FULLSPEED1;
1695                         break;
1696                 case USB_SPEED_HIGH:
1697                         reg |= DWC3_DCFG_HIGHSPEED;
1698                         break;
1699                 case USB_SPEED_SUPER_PLUS:
1700                         reg |= DWC3_DCFG_SUPERSPEED_PLUS;
1701                         break;
1702                 default:
1703                         dev_err(dwc->dev, "invalid dwc->maximum_speed (%d)\n",
1704                                 dwc->maximum_speed);
1705                         /* fall through */
1706                 case USB_SPEED_SUPER:
1707                         reg |= DWC3_DCFG_SUPERSPEED;
1708                         break;
1709                 }
1710         }
1711         dwc3_writel(dwc->regs, DWC3_DCFG, reg);
1712
1713         /*
1714          * We are telling dwc3 that we want to use DCFG.NUMP as ACK TP's NUMP
1715          * field instead of letting dwc3 itself calculate that automatically.
1716          *
1717          * This way, we maximize the chances that we'll be able to get several
1718          * bursts of data without going through any sort of endpoint throttling.
1719          */
1720         reg = dwc3_readl(dwc->regs, DWC3_GRXTHRCFG);
1721         reg &= ~DWC3_GRXTHRCFG_PKTCNTSEL;
1722         dwc3_writel(dwc->regs, DWC3_GRXTHRCFG, reg);
1723
1724         dwc3_gadget_setup_nump(dwc);
1725
1726         /* Start with SuperSpeed Default */
1727         dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
1728
1729         dep = dwc->eps[0];
1730         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
1731                         false);
1732         if (ret) {
1733                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
1734                 goto err0;
1735         }
1736
1737         dep = dwc->eps[1];
1738         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
1739                         false);
1740         if (ret) {
1741                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
1742                 goto err1;
1743         }
1744
1745         /* begin to receive SETUP packets */
1746         dwc->ep0state = EP0_SETUP_PHASE;
1747         dwc3_ep0_out_start(dwc);
1748
1749         dwc3_gadget_enable_irq(dwc);
1750
1751         return 0;
1752
1753 err1:
1754         __dwc3_gadget_ep_disable(dwc->eps[0]);
1755
1756 err0:
1757         return ret;
1758 }
1759
1760 static int dwc3_gadget_start(struct usb_gadget *g,
1761                 struct usb_gadget_driver *driver)
1762 {
1763         struct dwc3             *dwc = gadget_to_dwc(g);
1764         unsigned long           flags;
1765         int                     ret = 0;
1766         int                     irq;
1767
1768         irq = dwc->irq_gadget;
1769         ret = request_threaded_irq(irq, dwc3_interrupt, dwc3_thread_interrupt,
1770                         IRQF_SHARED, "dwc3", dwc->ev_buf);
1771         if (ret) {
1772                 dev_err(dwc->dev, "failed to request irq #%d --> %d\n",
1773                                 irq, ret);
1774                 goto err0;
1775         }
1776
1777         spin_lock_irqsave(&dwc->lock, flags);
1778         if (dwc->gadget_driver) {
1779                 dev_err(dwc->dev, "%s is already bound to %s\n",
1780                                 dwc->gadget.name,
1781                                 dwc->gadget_driver->driver.name);
1782                 ret = -EBUSY;
1783                 goto err1;
1784         }
1785
1786         dwc->gadget_driver      = driver;
1787
1788         if (pm_runtime_active(dwc->dev))
1789                 __dwc3_gadget_start(dwc);
1790
1791         spin_unlock_irqrestore(&dwc->lock, flags);
1792
1793         return 0;
1794
1795 err1:
1796         spin_unlock_irqrestore(&dwc->lock, flags);
1797         free_irq(irq, dwc);
1798
1799 err0:
1800         return ret;
1801 }
1802
1803 static void __dwc3_gadget_stop(struct dwc3 *dwc)
1804 {
1805         if (pm_runtime_suspended(dwc->dev))
1806                 return;
1807
1808         dwc3_gadget_disable_irq(dwc);
1809         __dwc3_gadget_ep_disable(dwc->eps[0]);
1810         __dwc3_gadget_ep_disable(dwc->eps[1]);
1811 }
1812
1813 static int dwc3_gadget_stop(struct usb_gadget *g)
1814 {
1815         struct dwc3             *dwc = gadget_to_dwc(g);
1816         unsigned long           flags;
1817
1818         spin_lock_irqsave(&dwc->lock, flags);
1819         __dwc3_gadget_stop(dwc);
1820         dwc->gadget_driver      = NULL;
1821         spin_unlock_irqrestore(&dwc->lock, flags);
1822
1823         free_irq(dwc->irq_gadget, dwc->ev_buf);
1824
1825         return 0;
1826 }
1827
1828 static const struct usb_gadget_ops dwc3_gadget_ops = {
1829         .get_frame              = dwc3_gadget_get_frame,
1830         .wakeup                 = dwc3_gadget_wakeup,
1831         .set_selfpowered        = dwc3_gadget_set_selfpowered,
1832         .pullup                 = dwc3_gadget_pullup,
1833         .udc_start              = dwc3_gadget_start,
1834         .udc_stop               = dwc3_gadget_stop,
1835 };
1836
1837 /* -------------------------------------------------------------------------- */
1838
1839 static int dwc3_gadget_init_hw_endpoints(struct dwc3 *dwc,
1840                 u8 num, u32 direction)
1841 {
1842         struct dwc3_ep                  *dep;
1843         u8                              i;
1844
1845         for (i = 0; i < num; i++) {
1846                 u8 epnum = (i << 1) | (direction ? 1 : 0);
1847
1848                 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
1849                 if (!dep)
1850                         return -ENOMEM;
1851
1852                 dep->dwc = dwc;
1853                 dep->number = epnum;
1854                 dep->direction = !!direction;
1855                 dep->regs = dwc->regs + DWC3_DEP_BASE(epnum);
1856                 dwc->eps[epnum] = dep;
1857
1858                 snprintf(dep->name, sizeof(dep->name), "ep%d%s", epnum >> 1,
1859                                 (epnum & 1) ? "in" : "out");
1860
1861                 dep->endpoint.name = dep->name;
1862                 spin_lock_init(&dep->lock);
1863
1864                 dwc3_trace(trace_dwc3_gadget, "initializing %s", dep->name);
1865
1866                 if (epnum == 0 || epnum == 1) {
1867                         usb_ep_set_maxpacket_limit(&dep->endpoint, 512);
1868                         dep->endpoint.maxburst = 1;
1869                         dep->endpoint.ops = &dwc3_gadget_ep0_ops;
1870                         if (!epnum)
1871                                 dwc->gadget.ep0 = &dep->endpoint;
1872                 } else {
1873                         int             ret;
1874
1875                         usb_ep_set_maxpacket_limit(&dep->endpoint, 1024);
1876                         dep->endpoint.max_streams = 15;
1877                         dep->endpoint.ops = &dwc3_gadget_ep_ops;
1878                         list_add_tail(&dep->endpoint.ep_list,
1879                                         &dwc->gadget.ep_list);
1880
1881                         ret = dwc3_alloc_trb_pool(dep);
1882                         if (ret)
1883                                 return ret;
1884                 }
1885
1886                 if (epnum == 0 || epnum == 1) {
1887                         dep->endpoint.caps.type_control = true;
1888                 } else {
1889                         dep->endpoint.caps.type_iso = true;
1890                         dep->endpoint.caps.type_bulk = true;
1891                         dep->endpoint.caps.type_int = true;
1892                 }
1893
1894                 dep->endpoint.caps.dir_in = !!direction;
1895                 dep->endpoint.caps.dir_out = !direction;
1896
1897                 INIT_LIST_HEAD(&dep->pending_list);
1898                 INIT_LIST_HEAD(&dep->started_list);
1899         }
1900
1901         return 0;
1902 }
1903
1904 static int dwc3_gadget_init_endpoints(struct dwc3 *dwc)
1905 {
1906         int                             ret;
1907
1908         INIT_LIST_HEAD(&dwc->gadget.ep_list);
1909
1910         ret = dwc3_gadget_init_hw_endpoints(dwc, dwc->num_out_eps, 0);
1911         if (ret < 0) {
1912                 dwc3_trace(trace_dwc3_gadget,
1913                                 "failed to allocate OUT endpoints");
1914                 return ret;
1915         }
1916
1917         ret = dwc3_gadget_init_hw_endpoints(dwc, dwc->num_in_eps, 1);
1918         if (ret < 0) {
1919                 dwc3_trace(trace_dwc3_gadget,
1920                                 "failed to allocate IN endpoints");
1921                 return ret;
1922         }
1923
1924         return 0;
1925 }
1926
1927 static void dwc3_gadget_free_endpoints(struct dwc3 *dwc)
1928 {
1929         struct dwc3_ep                  *dep;
1930         u8                              epnum;
1931
1932         for (epnum = 0; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
1933                 dep = dwc->eps[epnum];
1934                 if (!dep)
1935                         continue;
1936                 /*
1937                  * Physical endpoints 0 and 1 are special; they form the
1938                  * bi-directional USB endpoint 0.
1939                  *
1940                  * For those two physical endpoints, we don't allocate a TRB
1941                  * pool nor do we add them the endpoints list. Due to that, we
1942                  * shouldn't do these two operations otherwise we would end up
1943                  * with all sorts of bugs when removing dwc3.ko.
1944                  */
1945                 if (epnum != 0 && epnum != 1) {
1946                         dwc3_free_trb_pool(dep);
1947                         list_del(&dep->endpoint.ep_list);
1948                 }
1949
1950                 kfree(dep);
1951         }
1952 }
1953
1954 /* -------------------------------------------------------------------------- */
1955
1956 static int __dwc3_cleanup_done_trbs(struct dwc3 *dwc, struct dwc3_ep *dep,
1957                 struct dwc3_request *req, struct dwc3_trb *trb,
1958                 const struct dwc3_event_depevt *event, int status)
1959 {
1960         unsigned int            count;
1961         unsigned int            s_pkt = 0;
1962         unsigned int            trb_status;
1963
1964         dep->queued_requests--;
1965         trace_dwc3_complete_trb(dep, trb);
1966
1967         if ((trb->ctrl & DWC3_TRB_CTRL_HWO) && status != -ESHUTDOWN)
1968                 /*
1969                  * We continue despite the error. There is not much we
1970                  * can do. If we don't clean it up we loop forever. If
1971                  * we skip the TRB then it gets overwritten after a
1972                  * while since we use them in a ring buffer. A BUG()
1973                  * would help. Lets hope that if this occurs, someone
1974                  * fixes the root cause instead of looking away :)
1975                  */
1976                 dev_err(dwc->dev, "%s's TRB (%p) still owned by HW\n",
1977                                 dep->name, trb);
1978         count = trb->size & DWC3_TRB_SIZE_MASK;
1979
1980         if (dep->direction) {
1981                 if (count) {
1982                         trb_status = DWC3_TRB_SIZE_TRBSTS(trb->size);
1983                         if (trb_status == DWC3_TRBSTS_MISSED_ISOC) {
1984                                 dwc3_trace(trace_dwc3_gadget,
1985                                                 "%s: incomplete IN transfer",
1986                                                 dep->name);
1987                                 /*
1988                                  * If missed isoc occurred and there is
1989                                  * no request queued then issue END
1990                                  * TRANSFER, so that core generates
1991                                  * next xfernotready and we will issue
1992                                  * a fresh START TRANSFER.
1993                                  * If there are still queued request
1994                                  * then wait, do not issue either END
1995                                  * or UPDATE TRANSFER, just attach next
1996                                  * request in pending_list during
1997                                  * giveback.If any future queued request
1998                                  * is successfully transferred then we
1999                                  * will issue UPDATE TRANSFER for all
2000                                  * request in the pending_list.
2001                                  */
2002                                 dep->flags |= DWC3_EP_MISSED_ISOC;
2003                         } else {
2004                                 dev_err(dwc->dev, "incomplete IN transfer %s\n",
2005                                                 dep->name);
2006                                 status = -ECONNRESET;
2007                         }
2008                 } else {
2009                         dep->flags &= ~DWC3_EP_MISSED_ISOC;
2010                 }
2011         } else {
2012                 if (count && (event->status & DEPEVT_STATUS_SHORT))
2013                         s_pkt = 1;
2014         }
2015
2016         /*
2017          * We assume here we will always receive the entire data block
2018          * which we should receive. Meaning, if we program RX to
2019          * receive 4K but we receive only 2K, we assume that's all we
2020          * should receive and we simply bounce the request back to the
2021          * gadget driver for further processing.
2022          */
2023         req->request.actual += req->request.length - count;
2024         if (s_pkt)
2025                 return 1;
2026         if ((event->status & DEPEVT_STATUS_LST) &&
2027                         (trb->ctrl & (DWC3_TRB_CTRL_LST |
2028                                 DWC3_TRB_CTRL_HWO)))
2029                 return 1;
2030         if ((event->status & DEPEVT_STATUS_IOC) &&
2031                         (trb->ctrl & DWC3_TRB_CTRL_IOC))
2032                 return 1;
2033         return 0;
2034 }
2035
2036 static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
2037                 const struct dwc3_event_depevt *event, int status)
2038 {
2039         struct dwc3_request     *req;
2040         struct dwc3_trb         *trb;
2041         unsigned int            slot;
2042         unsigned int            i;
2043         int                     ret;
2044
2045         do {
2046                 req = next_request(&dep->started_list);
2047                 if (WARN_ON_ONCE(!req))
2048                         return 1;
2049
2050                 i = 0;
2051                 do {
2052                         slot = req->first_trb_index + i;
2053                         if (slot == DWC3_TRB_NUM - 1)
2054                                 slot++;
2055                         slot %= DWC3_TRB_NUM;
2056                         trb = &dep->trb_pool[slot];
2057
2058                         ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
2059                                         event, status);
2060                         if (ret)
2061                                 break;
2062                 } while (++i < req->request.num_mapped_sgs);
2063
2064                 dwc3_gadget_giveback(dep, req, status);
2065
2066                 if (ret)
2067                         break;
2068         } while (1);
2069
2070         /*
2071          * Our endpoint might get disabled by another thread during
2072          * dwc3_gadget_giveback(). If that happens, we're just gonna return 1
2073          * early on so DWC3_EP_BUSY flag gets cleared
2074          */
2075         if (!dep->endpoint.desc)
2076                 return 1;
2077
2078         if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
2079                         list_empty(&dep->started_list)) {
2080                 if (list_empty(&dep->pending_list)) {
2081                         /*
2082                          * If there is no entry in request list then do
2083                          * not issue END TRANSFER now. Just set PENDING
2084                          * flag, so that END TRANSFER is issued when an
2085                          * entry is added into request list.
2086                          */
2087                         dep->flags = DWC3_EP_PENDING_REQUEST;
2088                 } else {
2089                         dwc3_stop_active_transfer(dwc, dep->number, true);
2090                         dep->flags = DWC3_EP_ENABLED;
2091                 }
2092                 return 1;
2093         }
2094
2095         if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
2096                 if ((event->status & DEPEVT_STATUS_IOC) &&
2097                                 (trb->ctrl & DWC3_TRB_CTRL_IOC))
2098                         return 0;
2099         return 1;
2100 }
2101
2102 static void dwc3_endpoint_transfer_complete(struct dwc3 *dwc,
2103                 struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
2104 {
2105         unsigned                status = 0;
2106         int                     clean_busy;
2107         u32                     is_xfer_complete;
2108
2109         is_xfer_complete = (event->endpoint_event == DWC3_DEPEVT_XFERCOMPLETE);
2110
2111         if (event->status & DEPEVT_STATUS_BUSERR)
2112                 status = -ECONNRESET;
2113
2114         clean_busy = dwc3_cleanup_done_reqs(dwc, dep, event, status);
2115         if (clean_busy && (!dep->endpoint.desc || is_xfer_complete ||
2116                                 usb_endpoint_xfer_isoc(dep->endpoint.desc)))
2117                 dep->flags &= ~DWC3_EP_BUSY;
2118
2119         /*
2120          * WORKAROUND: This is the 2nd half of U1/U2 -> U0 workaround.
2121          * See dwc3_gadget_linksts_change_interrupt() for 1st half.
2122          */
2123         if (dwc->revision < DWC3_REVISION_183A) {
2124                 u32             reg;
2125                 int             i;
2126
2127                 for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
2128                         dep = dwc->eps[i];
2129
2130                         if (!(dep->flags & DWC3_EP_ENABLED))
2131                                 continue;
2132
2133                         if (!list_empty(&dep->started_list))
2134                                 return;
2135                 }
2136
2137                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2138                 reg |= dwc->u1u2;
2139                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2140
2141                 dwc->u1u2 = 0;
2142         }
2143
2144         /*
2145          * Our endpoint might get disabled by another thread during
2146          * dwc3_gadget_giveback(). If that happens, we're just gonna return 1
2147          * early on so DWC3_EP_BUSY flag gets cleared
2148          */
2149         if (!dep->endpoint.desc)
2150                 return;
2151
2152         if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
2153                 int ret;
2154
2155                 ret = __dwc3_gadget_kick_transfer(dep, 0);
2156                 if (!ret || ret == -EBUSY)
2157                         return;
2158         }
2159 }
2160
2161 static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
2162                 const struct dwc3_event_depevt *event)
2163 {
2164         struct dwc3_ep          *dep;
2165         u8                      epnum = event->endpoint_number;
2166
2167         dep = dwc->eps[epnum];
2168
2169         if (!(dep->flags & DWC3_EP_ENABLED))
2170                 return;
2171
2172         if (epnum == 0 || epnum == 1) {
2173                 dwc3_ep0_interrupt(dwc, event);
2174                 return;
2175         }
2176
2177         switch (event->endpoint_event) {
2178         case DWC3_DEPEVT_XFERCOMPLETE:
2179                 dep->resource_index = 0;
2180
2181                 if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
2182                         dwc3_trace(trace_dwc3_gadget,
2183                                         "%s is an Isochronous endpoint",
2184                                         dep->name);
2185                         return;
2186                 }
2187
2188                 dwc3_endpoint_transfer_complete(dwc, dep, event);
2189                 break;
2190         case DWC3_DEPEVT_XFERINPROGRESS:
2191                 dwc3_endpoint_transfer_complete(dwc, dep, event);
2192                 break;
2193         case DWC3_DEPEVT_XFERNOTREADY:
2194                 if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
2195                         dwc3_gadget_start_isoc(dwc, dep, event);
2196                 } else {
2197                         int active;
2198                         int ret;
2199
2200                         active = event->status & DEPEVT_STATUS_TRANSFER_ACTIVE;
2201
2202                         dwc3_trace(trace_dwc3_gadget, "%s: reason %s",
2203                                         dep->name, active ? "Transfer Active"
2204                                         : "Transfer Not Active");
2205
2206                         ret = __dwc3_gadget_kick_transfer(dep, 0);
2207                         if (!ret || ret == -EBUSY)
2208                                 return;
2209
2210                         dwc3_trace(trace_dwc3_gadget,
2211                                         "%s: failed to kick transfers",
2212                                         dep->name);
2213                 }
2214
2215                 break;
2216         case DWC3_DEPEVT_STREAMEVT:
2217                 if (!usb_endpoint_xfer_bulk(dep->endpoint.desc)) {
2218                         dev_err(dwc->dev, "Stream event for non-Bulk %s\n",
2219                                         dep->name);
2220                         return;
2221                 }
2222
2223                 switch (event->status) {
2224                 case DEPEVT_STREAMEVT_FOUND:
2225                         dwc3_trace(trace_dwc3_gadget,
2226                                         "Stream %d found and started",
2227                                         event->parameters);
2228
2229                         break;
2230                 case DEPEVT_STREAMEVT_NOTFOUND:
2231                         /* FALLTHROUGH */
2232                 default:
2233                         dwc3_trace(trace_dwc3_gadget,
2234                                         "unable to find suitable stream");
2235                 }
2236                 break;
2237         case DWC3_DEPEVT_RXTXFIFOEVT:
2238                 dwc3_trace(trace_dwc3_gadget, "%s FIFO Overrun", dep->name);
2239                 break;
2240         case DWC3_DEPEVT_EPCMDCMPLT:
2241                 dwc3_trace(trace_dwc3_gadget, "Endpoint Command Complete");
2242                 break;
2243         }
2244 }
2245
2246 static void dwc3_disconnect_gadget(struct dwc3 *dwc)
2247 {
2248         if (dwc->gadget_driver && dwc->gadget_driver->disconnect) {
2249                 spin_unlock(&dwc->lock);
2250                 dwc->gadget_driver->disconnect(&dwc->gadget);
2251                 spin_lock(&dwc->lock);
2252         }
2253 }
2254
2255 static void dwc3_suspend_gadget(struct dwc3 *dwc)
2256 {
2257         if (dwc->gadget_driver && dwc->gadget_driver->suspend) {
2258                 spin_unlock(&dwc->lock);
2259                 dwc->gadget_driver->suspend(&dwc->gadget);
2260                 spin_lock(&dwc->lock);
2261         }
2262 }
2263
2264 static void dwc3_resume_gadget(struct dwc3 *dwc)
2265 {
2266         if (dwc->gadget_driver && dwc->gadget_driver->resume) {
2267                 spin_unlock(&dwc->lock);
2268                 dwc->gadget_driver->resume(&dwc->gadget);
2269                 spin_lock(&dwc->lock);
2270         }
2271 }
2272
2273 static void dwc3_reset_gadget(struct dwc3 *dwc)
2274 {
2275         if (!dwc->gadget_driver)
2276                 return;
2277
2278         if (dwc->gadget.speed != USB_SPEED_UNKNOWN) {
2279                 spin_unlock(&dwc->lock);
2280                 usb_gadget_udc_reset(&dwc->gadget, dwc->gadget_driver);
2281                 spin_lock(&dwc->lock);
2282         }
2283 }
2284
2285 static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force)
2286 {
2287         struct dwc3_ep *dep;
2288         struct dwc3_gadget_ep_cmd_params params;
2289         u32 cmd;
2290         int ret;
2291
2292         dep = dwc->eps[epnum];
2293
2294         if (!dep->resource_index)
2295                 return;
2296
2297         /*
2298          * NOTICE: We are violating what the Databook says about the
2299          * EndTransfer command. Ideally we would _always_ wait for the
2300          * EndTransfer Command Completion IRQ, but that's causing too
2301          * much trouble synchronizing between us and gadget driver.
2302          *
2303          * We have discussed this with the IP Provider and it was
2304          * suggested to giveback all requests here, but give HW some
2305          * extra time to synchronize with the interconnect. We're using
2306          * an arbitrary 100us delay for that.
2307          *
2308          * Note also that a similar handling was tested by Synopsys
2309          * (thanks a lot Paul) and nothing bad has come out of it.
2310          * In short, what we're doing is:
2311          *
2312          * - Issue EndTransfer WITH CMDIOC bit set
2313          * - Wait 100us
2314          */
2315
2316         cmd = DWC3_DEPCMD_ENDTRANSFER;
2317         cmd |= force ? DWC3_DEPCMD_HIPRI_FORCERM : 0;
2318         cmd |= DWC3_DEPCMD_CMDIOC;
2319         cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
2320         memset(&params, 0, sizeof(params));
2321         ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
2322         WARN_ON_ONCE(ret);
2323         dep->resource_index = 0;
2324         dep->flags &= ~DWC3_EP_BUSY;
2325         udelay(100);
2326 }
2327
2328 static void dwc3_stop_active_transfers(struct dwc3 *dwc)
2329 {
2330         u32 epnum;
2331
2332         for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
2333                 struct dwc3_ep *dep;
2334
2335                 dep = dwc->eps[epnum];
2336                 if (!dep)
2337                         continue;
2338
2339                 if (!(dep->flags & DWC3_EP_ENABLED))
2340                         continue;
2341
2342                 dwc3_remove_requests(dwc, dep);
2343         }
2344 }
2345
2346 static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)
2347 {
2348         u32 epnum;
2349
2350         for (epnum = 1; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
2351                 struct dwc3_ep *dep;
2352                 int ret;
2353
2354                 dep = dwc->eps[epnum];
2355                 if (!dep)
2356                         continue;
2357
2358                 if (!(dep->flags & DWC3_EP_STALL))
2359                         continue;
2360
2361                 dep->flags &= ~DWC3_EP_STALL;
2362
2363                 ret = dwc3_send_clear_stall_ep_cmd(dep);
2364                 WARN_ON_ONCE(ret);
2365         }
2366 }
2367
2368 static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
2369 {
2370         int                     reg;
2371
2372         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2373         reg &= ~DWC3_DCTL_INITU1ENA;
2374         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2375
2376         reg &= ~DWC3_DCTL_INITU2ENA;
2377         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2378
2379         dwc3_disconnect_gadget(dwc);
2380
2381         dwc->gadget.speed = USB_SPEED_UNKNOWN;
2382         dwc->setup_packet_pending = false;
2383         usb_gadget_set_state(&dwc->gadget, USB_STATE_NOTATTACHED);
2384
2385         dwc->connected = false;
2386 }
2387
2388 static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
2389 {
2390         u32                     reg;
2391
2392         dwc->connected = true;
2393
2394         /*
2395          * WORKAROUND: DWC3 revisions <1.88a have an issue which
2396          * would cause a missing Disconnect Event if there's a
2397          * pending Setup Packet in the FIFO.
2398          *
2399          * There's no suggested workaround on the official Bug
2400          * report, which states that "unless the driver/application
2401          * is doing any special handling of a disconnect event,
2402          * there is no functional issue".
2403          *
2404          * Unfortunately, it turns out that we _do_ some special
2405          * handling of a disconnect event, namely complete all
2406          * pending transfers, notify gadget driver of the
2407          * disconnection, and so on.
2408          *
2409          * Our suggested workaround is to follow the Disconnect
2410          * Event steps here, instead, based on a setup_packet_pending
2411          * flag. Such flag gets set whenever we have a SETUP_PENDING
2412          * status for EP0 TRBs and gets cleared on XferComplete for the
2413          * same endpoint.
2414          *
2415          * Refers to:
2416          *
2417          * STAR#9000466709: RTL: Device : Disconnect event not
2418          * generated if setup packet pending in FIFO
2419          */
2420         if (dwc->revision < DWC3_REVISION_188A) {
2421                 if (dwc->setup_packet_pending)
2422                         dwc3_gadget_disconnect_interrupt(dwc);
2423         }
2424
2425         dwc3_reset_gadget(dwc);
2426
2427         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2428         reg &= ~DWC3_DCTL_TSTCTRL_MASK;
2429         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2430         dwc->test_mode = false;
2431
2432         dwc3_stop_active_transfers(dwc);
2433         dwc3_clear_stall_all_ep(dwc);
2434
2435         /* Reset device address to zero */
2436         reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2437         reg &= ~(DWC3_DCFG_DEVADDR_MASK);
2438         dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2439 }
2440
2441 static void dwc3_update_ram_clk_sel(struct dwc3 *dwc, u32 speed)
2442 {
2443         u32 reg;
2444         u32 usb30_clock = DWC3_GCTL_CLK_BUS;
2445
2446         /*
2447          * We change the clock only at SS but I dunno why I would want to do
2448          * this. Maybe it becomes part of the power saving plan.
2449          */
2450
2451         if ((speed != DWC3_DSTS_SUPERSPEED) &&
2452             (speed != DWC3_DSTS_SUPERSPEED_PLUS))
2453                 return;
2454
2455         /*
2456          * RAMClkSel is reset to 0 after USB reset, so it must be reprogrammed
2457          * each time on Connect Done.
2458          */
2459         if (!usb30_clock)
2460                 return;
2461
2462         reg = dwc3_readl(dwc->regs, DWC3_GCTL);
2463         reg |= DWC3_GCTL_RAMCLKSEL(usb30_clock);
2464         dwc3_writel(dwc->regs, DWC3_GCTL, reg);
2465 }
2466
2467 static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
2468 {
2469         struct dwc3_ep          *dep;
2470         int                     ret;
2471         u32                     reg;
2472         u8                      speed;
2473
2474         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
2475         speed = reg & DWC3_DSTS_CONNECTSPD;
2476         dwc->speed = speed;
2477
2478         dwc3_update_ram_clk_sel(dwc, speed);
2479
2480         switch (speed) {
2481         case DWC3_DSTS_SUPERSPEED_PLUS:
2482                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
2483                 dwc->gadget.ep0->maxpacket = 512;
2484                 dwc->gadget.speed = USB_SPEED_SUPER_PLUS;
2485                 break;
2486         case DWC3_DSTS_SUPERSPEED:
2487                 /*
2488                  * WORKAROUND: DWC3 revisions <1.90a have an issue which
2489                  * would cause a missing USB3 Reset event.
2490                  *
2491                  * In such situations, we should force a USB3 Reset
2492                  * event by calling our dwc3_gadget_reset_interrupt()
2493                  * routine.
2494                  *
2495                  * Refers to:
2496                  *
2497                  * STAR#9000483510: RTL: SS : USB3 reset event may
2498                  * not be generated always when the link enters poll
2499                  */
2500                 if (dwc->revision < DWC3_REVISION_190A)
2501                         dwc3_gadget_reset_interrupt(dwc);
2502
2503                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
2504                 dwc->gadget.ep0->maxpacket = 512;
2505                 dwc->gadget.speed = USB_SPEED_SUPER;
2506                 break;
2507         case DWC3_DSTS_HIGHSPEED:
2508                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
2509                 dwc->gadget.ep0->maxpacket = 64;
2510                 dwc->gadget.speed = USB_SPEED_HIGH;
2511                 break;
2512         case DWC3_DSTS_FULLSPEED2:
2513         case DWC3_DSTS_FULLSPEED1:
2514                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
2515                 dwc->gadget.ep0->maxpacket = 64;
2516                 dwc->gadget.speed = USB_SPEED_FULL;
2517                 break;
2518         case DWC3_DSTS_LOWSPEED:
2519                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(8);
2520                 dwc->gadget.ep0->maxpacket = 8;
2521                 dwc->gadget.speed = USB_SPEED_LOW;
2522                 break;
2523         }
2524
2525         /* Enable USB2 LPM Capability */
2526
2527         if ((dwc->revision > DWC3_REVISION_194A) &&
2528             (speed != DWC3_DSTS_SUPERSPEED) &&
2529             (speed != DWC3_DSTS_SUPERSPEED_PLUS)) {
2530                 reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2531                 reg |= DWC3_DCFG_LPM_CAP;
2532                 dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2533
2534                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2535                 reg &= ~(DWC3_DCTL_HIRD_THRES_MASK | DWC3_DCTL_L1_HIBER_EN);
2536
2537                 reg |= DWC3_DCTL_HIRD_THRES(dwc->hird_threshold);
2538
2539                 /*
2540                  * When dwc3 revisions >= 2.40a, LPM Erratum is enabled and
2541                  * DCFG.LPMCap is set, core responses with an ACK and the
2542                  * BESL value in the LPM token is less than or equal to LPM
2543                  * NYET threshold.
2544                  */
2545                 WARN_ONCE(dwc->revision < DWC3_REVISION_240A
2546                                 && dwc->has_lpm_erratum,
2547                                 "LPM Erratum not available on dwc3 revisisions < 2.40a\n");
2548
2549                 if (dwc->has_lpm_erratum && dwc->revision >= DWC3_REVISION_240A)
2550                         reg |= DWC3_DCTL_LPM_ERRATA(dwc->lpm_nyet_threshold);
2551
2552                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2553         } else {
2554                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2555                 reg &= ~DWC3_DCTL_HIRD_THRES_MASK;
2556                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2557         }
2558
2559         dep = dwc->eps[0];
2560         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true,
2561                         false);
2562         if (ret) {
2563                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
2564                 return;
2565         }
2566
2567         dep = dwc->eps[1];
2568         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true,
2569                         false);
2570         if (ret) {
2571                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
2572                 return;
2573         }
2574
2575         /*
2576          * Configure PHY via GUSB3PIPECTLn if required.
2577          *
2578          * Update GTXFIFOSIZn
2579          *
2580          * In both cases reset values should be sufficient.
2581          */
2582 }
2583
2584 static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc)
2585 {
2586         /*
2587          * TODO take core out of low power mode when that's
2588          * implemented.
2589          */
2590
2591         if (dwc->gadget_driver && dwc->gadget_driver->resume) {
2592                 spin_unlock(&dwc->lock);
2593                 dwc->gadget_driver->resume(&dwc->gadget);
2594                 spin_lock(&dwc->lock);
2595         }
2596 }
2597
2598 static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
2599                 unsigned int evtinfo)
2600 {
2601         enum dwc3_link_state    next = evtinfo & DWC3_LINK_STATE_MASK;
2602         unsigned int            pwropt;
2603
2604         /*
2605          * WORKAROUND: DWC3 < 2.50a have an issue when configured without
2606          * Hibernation mode enabled which would show up when device detects
2607          * host-initiated U3 exit.
2608          *
2609          * In that case, device will generate a Link State Change Interrupt
2610          * from U3 to RESUME which is only necessary if Hibernation is
2611          * configured in.
2612          *
2613          * There are no functional changes due to such spurious event and we
2614          * just need to ignore it.
2615          *
2616          * Refers to:
2617          *
2618          * STAR#9000570034 RTL: SS Resume event generated in non-Hibernation
2619          * operational mode
2620          */
2621         pwropt = DWC3_GHWPARAMS1_EN_PWROPT(dwc->hwparams.hwparams1);
2622         if ((dwc->revision < DWC3_REVISION_250A) &&
2623                         (pwropt != DWC3_GHWPARAMS1_EN_PWROPT_HIB)) {
2624                 if ((dwc->link_state == DWC3_LINK_STATE_U3) &&
2625                                 (next == DWC3_LINK_STATE_RESUME)) {
2626                         dwc3_trace(trace_dwc3_gadget,
2627                                         "ignoring transition U3 -> Resume");
2628                         return;
2629                 }
2630         }
2631
2632         /*
2633          * WORKAROUND: DWC3 Revisions <1.83a have an issue which, depending
2634          * on the link partner, the USB session might do multiple entry/exit
2635          * of low power states before a transfer takes place.
2636          *
2637          * Due to this problem, we might experience lower throughput. The
2638          * suggested workaround is to disable DCTL[12:9] bits if we're
2639          * transitioning from U1/U2 to U0 and enable those bits again
2640          * after a transfer completes and there are no pending transfers
2641          * on any of the enabled endpoints.
2642          *
2643          * This is the first half of that workaround.
2644          *
2645          * Refers to:
2646          *
2647          * STAR#9000446952: RTL: Device SS : if U1/U2 ->U0 takes >128us
2648          * core send LGO_Ux entering U0
2649          */
2650         if (dwc->revision < DWC3_REVISION_183A) {
2651                 if (next == DWC3_LINK_STATE_U0) {
2652                         u32     u1u2;
2653                         u32     reg;
2654
2655                         switch (dwc->link_state) {
2656                         case DWC3_LINK_STATE_U1:
2657                         case DWC3_LINK_STATE_U2:
2658                                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2659                                 u1u2 = reg & (DWC3_DCTL_INITU2ENA
2660                                                 | DWC3_DCTL_ACCEPTU2ENA
2661                                                 | DWC3_DCTL_INITU1ENA
2662                                                 | DWC3_DCTL_ACCEPTU1ENA);
2663
2664                                 if (!dwc->u1u2)
2665                                         dwc->u1u2 = reg & u1u2;
2666
2667                                 reg &= ~u1u2;
2668
2669                                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2670                                 break;
2671                         default:
2672                                 /* do nothing */
2673                                 break;
2674                         }
2675                 }
2676         }
2677
2678         switch (next) {
2679         case DWC3_LINK_STATE_U1:
2680                 if (dwc->speed == USB_SPEED_SUPER)
2681                         dwc3_suspend_gadget(dwc);
2682                 break;
2683         case DWC3_LINK_STATE_U2:
2684         case DWC3_LINK_STATE_U3:
2685                 dwc3_suspend_gadget(dwc);
2686                 break;
2687         case DWC3_LINK_STATE_RESUME:
2688                 dwc3_resume_gadget(dwc);
2689                 break;
2690         default:
2691                 /* do nothing */
2692                 break;
2693         }
2694
2695         dwc->link_state = next;
2696 }
2697
2698 static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
2699                                           unsigned int evtinfo)
2700 {
2701         enum dwc3_link_state next = evtinfo & DWC3_LINK_STATE_MASK;
2702
2703         if (dwc->link_state != next && next == DWC3_LINK_STATE_U3)
2704                 dwc3_suspend_gadget(dwc);
2705
2706         dwc->link_state = next;
2707 }
2708
2709 static void dwc3_gadget_hibernation_interrupt(struct dwc3 *dwc,
2710                 unsigned int evtinfo)
2711 {
2712         unsigned int is_ss = evtinfo & BIT(4);
2713
2714         /**
2715          * WORKAROUND: DWC3 revison 2.20a with hibernation support
2716          * have a known issue which can cause USB CV TD.9.23 to fail
2717          * randomly.
2718          *
2719          * Because of this issue, core could generate bogus hibernation
2720          * events which SW needs to ignore.
2721          *
2722          * Refers to:
2723          *
2724          * STAR#9000546576: Device Mode Hibernation: Issue in USB 2.0
2725          * Device Fallback from SuperSpeed
2726          */
2727         if (is_ss ^ (dwc->speed == USB_SPEED_SUPER))
2728                 return;
2729
2730         /* enter hibernation here */
2731 }
2732
2733 static void dwc3_gadget_interrupt(struct dwc3 *dwc,
2734                 const struct dwc3_event_devt *event)
2735 {
2736         switch (event->type) {
2737         case DWC3_DEVICE_EVENT_DISCONNECT:
2738                 dwc3_gadget_disconnect_interrupt(dwc);
2739                 break;
2740         case DWC3_DEVICE_EVENT_RESET:
2741                 dwc3_gadget_reset_interrupt(dwc);
2742                 break;
2743         case DWC3_DEVICE_EVENT_CONNECT_DONE:
2744                 dwc3_gadget_conndone_interrupt(dwc);
2745                 break;
2746         case DWC3_DEVICE_EVENT_WAKEUP:
2747                 dwc3_gadget_wakeup_interrupt(dwc);
2748                 break;
2749         case DWC3_DEVICE_EVENT_HIBER_REQ:
2750                 if (dev_WARN_ONCE(dwc->dev, !dwc->has_hibernation,
2751                                         "unexpected hibernation event\n"))
2752                         break;
2753
2754                 dwc3_gadget_hibernation_interrupt(dwc, event->event_info);
2755                 break;
2756         case DWC3_DEVICE_EVENT_LINK_STATUS_CHANGE:
2757                 dwc3_gadget_linksts_change_interrupt(dwc, event->event_info);
2758                 break;
2759         case DWC3_DEVICE_EVENT_EOPF:
2760                 /* It changed to be suspend event for version 2.30a and above */
2761                 if (dwc->revision < DWC3_REVISION_230A) {
2762                         dwc3_trace(trace_dwc3_gadget, "End of Periodic Frame");
2763                 } else {
2764                         dwc3_trace(trace_dwc3_gadget, "U3/L1-L2 Suspend Event");
2765
2766                         /*
2767                          * Ignore suspend event until the gadget enters into
2768                          * USB_STATE_CONFIGURED state.
2769                          */
2770                         if (dwc->gadget.state >= USB_STATE_CONFIGURED)
2771                                 dwc3_gadget_suspend_interrupt(dwc,
2772                                                 event->event_info);
2773                 }
2774                 break;
2775         case DWC3_DEVICE_EVENT_SOF:
2776                 dwc3_trace(trace_dwc3_gadget, "Start of Periodic Frame");
2777                 break;
2778         case DWC3_DEVICE_EVENT_ERRATIC_ERROR:
2779                 dwc3_trace(trace_dwc3_gadget, "Erratic Error");
2780                 break;
2781         case DWC3_DEVICE_EVENT_CMD_CMPL:
2782                 dwc3_trace(trace_dwc3_gadget, "Command Complete");
2783                 break;
2784         case DWC3_DEVICE_EVENT_OVERFLOW:
2785                 dwc3_trace(trace_dwc3_gadget, "Overflow");
2786                 break;
2787         default:
2788                 dev_WARN(dwc->dev, "UNKNOWN IRQ %d\n", event->type);
2789         }
2790 }
2791
2792 static void dwc3_process_event_entry(struct dwc3 *dwc,
2793                 const union dwc3_event *event)
2794 {
2795         trace_dwc3_event(event->raw);
2796
2797         /* Endpoint IRQ, handle it and return early */
2798         if (event->type.is_devspec == 0) {
2799                 /* depevt */
2800                 return dwc3_endpoint_interrupt(dwc, &event->depevt);
2801         }
2802
2803         switch (event->type.type) {
2804         case DWC3_EVENT_TYPE_DEV:
2805                 dwc3_gadget_interrupt(dwc, &event->devt);
2806                 break;
2807         /* REVISIT what to do with Carkit and I2C events ? */
2808         default:
2809                 dev_err(dwc->dev, "UNKNOWN IRQ type %d\n", event->raw);
2810         }
2811 }
2812
2813 static irqreturn_t dwc3_process_event_buf(struct dwc3_event_buffer *evt)
2814 {
2815         struct dwc3 *dwc = evt->dwc;
2816         irqreturn_t ret = IRQ_NONE;
2817         int left;
2818         u32 reg;
2819
2820         left = evt->count;
2821
2822         if (!(evt->flags & DWC3_EVENT_PENDING))
2823                 return IRQ_NONE;
2824
2825         while (left > 0) {
2826                 union dwc3_event event;
2827
2828                 event.raw = *(u32 *) (evt->buf + evt->lpos);
2829
2830                 dwc3_process_event_entry(dwc, &event);
2831
2832                 /*
2833                  * FIXME we wrap around correctly to the next entry as
2834                  * almost all entries are 4 bytes in size. There is one
2835                  * entry which has 12 bytes which is a regular entry
2836                  * followed by 8 bytes data. ATM I don't know how
2837                  * things are organized if we get next to the a
2838                  * boundary so I worry about that once we try to handle
2839                  * that.
2840                  */
2841                 evt->lpos = (evt->lpos + 4) % DWC3_EVENT_BUFFERS_SIZE;
2842                 left -= 4;
2843
2844                 dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), 4);
2845         }
2846
2847         evt->count = 0;
2848         evt->flags &= ~DWC3_EVENT_PENDING;
2849         ret = IRQ_HANDLED;
2850
2851         /* Unmask interrupt */
2852         reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0));
2853         reg &= ~DWC3_GEVNTSIZ_INTMASK;
2854         dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
2855
2856         return ret;
2857 }
2858
2859 static irqreturn_t dwc3_thread_interrupt(int irq, void *_evt)
2860 {
2861         struct dwc3_event_buffer *evt = _evt;
2862         struct dwc3 *dwc = evt->dwc;
2863         unsigned long flags;
2864         irqreturn_t ret = IRQ_NONE;
2865
2866         spin_lock_irqsave(&dwc->lock, flags);
2867         ret = dwc3_process_event_buf(evt);
2868         spin_unlock_irqrestore(&dwc->lock, flags);
2869
2870         return ret;
2871 }
2872
2873 static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt)
2874 {
2875         struct dwc3 *dwc = evt->dwc;
2876         u32 count;
2877         u32 reg;
2878
2879         if (pm_runtime_suspended(dwc->dev)) {
2880                 pm_runtime_get(dwc->dev);
2881                 disable_irq_nosync(dwc->irq_gadget);
2882                 dwc->pending_events = true;
2883                 return IRQ_HANDLED;
2884         }
2885
2886         count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
2887         count &= DWC3_GEVNTCOUNT_MASK;
2888         if (!count)
2889                 return IRQ_NONE;
2890
2891         evt->count = count;
2892         evt->flags |= DWC3_EVENT_PENDING;
2893
2894         /* Mask interrupt */
2895         reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0));
2896         reg |= DWC3_GEVNTSIZ_INTMASK;
2897         dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
2898
2899         return IRQ_WAKE_THREAD;
2900 }
2901
2902 static irqreturn_t dwc3_interrupt(int irq, void *_evt)
2903 {
2904         struct dwc3_event_buffer        *evt = _evt;
2905
2906         return dwc3_check_event_buf(evt);
2907 }
2908
2909 /**
2910  * dwc3_gadget_init - Initializes gadget related registers
2911  * @dwc: pointer to our controller context structure
2912  *
2913  * Returns 0 on success otherwise negative errno.
2914  */
2915 int dwc3_gadget_init(struct dwc3 *dwc)
2916 {
2917         int ret, irq;
2918         struct platform_device *dwc3_pdev = to_platform_device(dwc->dev);
2919
2920         irq = platform_get_irq_byname(dwc3_pdev, "peripheral");
2921         if (irq == -EPROBE_DEFER)
2922                 return irq;
2923
2924         if (irq <= 0) {
2925                 irq = platform_get_irq_byname(dwc3_pdev, "dwc_usb3");
2926                 if (irq == -EPROBE_DEFER)
2927                         return irq;
2928
2929                 if (irq <= 0) {
2930                         irq = platform_get_irq(dwc3_pdev, 0);
2931                         if (irq <= 0) {
2932                                 if (irq != -EPROBE_DEFER) {
2933                                         dev_err(dwc->dev,
2934                                                 "missing peripheral IRQ\n");
2935                                 }
2936                                 if (!irq)
2937                                         irq = -EINVAL;
2938                                 return irq;
2939                         }
2940                 }
2941         }
2942
2943         dwc->irq_gadget = irq;
2944
2945         dwc->ctrl_req = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
2946                         &dwc->ctrl_req_addr, GFP_KERNEL);
2947         if (!dwc->ctrl_req) {
2948                 dev_err(dwc->dev, "failed to allocate ctrl request\n");
2949                 ret = -ENOMEM;
2950                 goto err0;
2951         }
2952
2953         dwc->ep0_trb = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2,
2954                         &dwc->ep0_trb_addr, GFP_KERNEL);
2955         if (!dwc->ep0_trb) {
2956                 dev_err(dwc->dev, "failed to allocate ep0 trb\n");
2957                 ret = -ENOMEM;
2958                 goto err1;
2959         }
2960
2961         dwc->setup_buf = kzalloc(DWC3_EP0_BOUNCE_SIZE, GFP_KERNEL);
2962         if (!dwc->setup_buf) {
2963                 ret = -ENOMEM;
2964                 goto err2;
2965         }
2966
2967         dwc->ep0_bounce = dma_alloc_coherent(dwc->dev,
2968                         DWC3_EP0_BOUNCE_SIZE, &dwc->ep0_bounce_addr,
2969                         GFP_KERNEL);
2970         if (!dwc->ep0_bounce) {
2971                 dev_err(dwc->dev, "failed to allocate ep0 bounce buffer\n");
2972                 ret = -ENOMEM;
2973                 goto err3;
2974         }
2975
2976         dwc->zlp_buf = kzalloc(DWC3_ZLP_BUF_SIZE, GFP_KERNEL);
2977         if (!dwc->zlp_buf) {
2978                 ret = -ENOMEM;
2979                 goto err4;
2980         }
2981
2982         dwc->gadget.ops                 = &dwc3_gadget_ops;
2983         dwc->gadget.speed               = USB_SPEED_UNKNOWN;
2984         dwc->gadget.sg_supported        = true;
2985         dwc->gadget.name                = "dwc3-gadget";
2986         dwc->gadget.is_otg              = dwc->dr_mode == USB_DR_MODE_OTG;
2987
2988         /*
2989          * FIXME We might be setting max_speed to <SUPER, however versions
2990          * <2.20a of dwc3 have an issue with metastability (documented
2991          * elsewhere in this driver) which tells us we can't set max speed to
2992          * anything lower than SUPER.
2993          *
2994          * Because gadget.max_speed is only used by composite.c and function
2995          * drivers (i.e. it won't go into dwc3's registers) we are allowing this
2996          * to happen so we avoid sending SuperSpeed Capability descriptor
2997          * together with our BOS descriptor as that could confuse host into
2998          * thinking we can handle super speed.
2999          *
3000          * Note that, in fact, we won't even support GetBOS requests when speed
3001          * is less than super speed because we don't have means, yet, to tell
3002          * composite.c that we are USB 2.0 + LPM ECN.
3003          */
3004         if (dwc->revision < DWC3_REVISION_220A)
3005                 dwc3_trace(trace_dwc3_gadget,
3006                                 "Changing max_speed on rev %08x",
3007                                 dwc->revision);
3008
3009         dwc->gadget.max_speed           = dwc->maximum_speed;
3010
3011         /*
3012          * Per databook, DWC3 needs buffer size to be aligned to MaxPacketSize
3013          * on ep out.
3014          */
3015         dwc->gadget.quirk_ep_out_aligned_size = true;
3016
3017         /*
3018          * REVISIT: Here we should clear all pending IRQs to be
3019          * sure we're starting from a well known location.
3020          */
3021
3022         ret = dwc3_gadget_init_endpoints(dwc);
3023         if (ret)
3024                 goto err5;
3025
3026         ret = usb_add_gadget_udc(dwc->dev, &dwc->gadget);
3027         if (ret) {
3028                 dev_err(dwc->dev, "failed to register udc\n");
3029                 goto err5;
3030         }
3031
3032         return 0;
3033
3034 err5:
3035         kfree(dwc->zlp_buf);
3036
3037 err4:
3038         dwc3_gadget_free_endpoints(dwc);
3039         dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
3040                         dwc->ep0_bounce, dwc->ep0_bounce_addr);
3041
3042 err3:
3043         kfree(dwc->setup_buf);
3044
3045 err2:
3046         dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
3047                         dwc->ep0_trb, dwc->ep0_trb_addr);
3048
3049 err1:
3050         dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
3051                         dwc->ctrl_req, dwc->ctrl_req_addr);
3052
3053 err0:
3054         return ret;
3055 }
3056
3057 /* -------------------------------------------------------------------------- */
3058
3059 void dwc3_gadget_exit(struct dwc3 *dwc)
3060 {
3061         usb_del_gadget_udc(&dwc->gadget);
3062
3063         dwc3_gadget_free_endpoints(dwc);
3064
3065         dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
3066                         dwc->ep0_bounce, dwc->ep0_bounce_addr);
3067
3068         kfree(dwc->setup_buf);
3069         kfree(dwc->zlp_buf);
3070
3071         dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
3072                         dwc->ep0_trb, dwc->ep0_trb_addr);
3073
3074         dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
3075                         dwc->ctrl_req, dwc->ctrl_req_addr);
3076 }
3077
3078 int dwc3_gadget_suspend(struct dwc3 *dwc)
3079 {
3080         int ret;
3081
3082         if (!dwc->gadget_driver)
3083                 return 0;
3084
3085         ret = dwc3_gadget_run_stop(dwc, false, false);
3086         if (ret < 0)
3087                 return ret;
3088
3089         dwc3_disconnect_gadget(dwc);
3090         __dwc3_gadget_stop(dwc);
3091
3092         return 0;
3093 }
3094
3095 int dwc3_gadget_resume(struct dwc3 *dwc)
3096 {
3097         int                     ret;
3098
3099         if (!dwc->gadget_driver)
3100                 return 0;
3101
3102         ret = __dwc3_gadget_start(dwc);
3103         if (ret < 0)
3104                 goto err0;
3105
3106         ret = dwc3_gadget_run_stop(dwc, true, false);
3107         if (ret < 0)
3108                 goto err1;
3109
3110         return 0;
3111
3112 err1:
3113         __dwc3_gadget_stop(dwc);
3114
3115 err0:
3116         return ret;
3117 }
3118
3119 void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
3120 {
3121         if (dwc->pending_events) {
3122                 dwc3_interrupt(dwc->irq_gadget, dwc->ev_buf);
3123                 dwc->pending_events = false;
3124                 enable_irq(dwc->irq_gadget);
3125         }
3126 }