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_gadget_resize_tx_fifos - reallocate fifo spaces for current use-case
 150  * @dwc: pointer to our context structure
 151  *
 152  * This function will a best effort FIFO allocation in order
 153  * to improve FIFO usage and throughput, while still allowing
 154  * us to enable as many endpoints as possible.
 155  *
 156  * Keep in mind that this operation will be highly dependent
 157  * on the configured size for RAM1 - which contains TxFifo -,
 158  * the amount of endpoints enabled on coreConsultant tool, and
 159  * the width of the Master Bus.
 160  *
 161  * In the ideal world, we would always be able to satisfy the
 162  * following equation:
 163  *
 164  * ((512 + 2 * MDWIDTH-Bytes) + (Number of IN Endpoints - 1) * \
 165  * (3 * (1024 + MDWIDTH-Bytes) + MDWIDTH-Bytes)) / MDWIDTH-Bytes
 166  *
 167  * Unfortunately, due to many variables that's not always the case.
 168  */
 169 int dwc3_gadget_resize_tx_fifos(struct dwc3 *dwc)
 170 {
 171         int             last_fifo_depth = 0;
 172         int             ram1_depth;
 173         int             fifo_size;
 174         int             mdwidth;
 175         int             num;
 176
 177         if (!dwc->needs_fifo_resize)
 178                 return 0;
 179
 180         ram1_depth = DWC3_RAM1_DEPTH(dwc->hwparams.hwparams7);
 181         mdwidth = DWC3_MDWIDTH(dwc->hwparams.hwparams0);
 182
 183         /* MDWIDTH is represented in bits, we need it in bytes */
 184         mdwidth >>= 3;
 185
 186         /*
 187          * FIXME For now we will only allocate 1 wMaxPacketSize space
 188          * for each enabled endpoint, later patches will come to
 189          * improve this algorithm so that we better use the internal
 190          * FIFO space
 191          */
 192         for (num = 0; num < dwc->num_in_eps; num++) {
 193                 /* bit0 indicates direction; 1 means IN ep */
 194                 struct dwc3_ep  *dep = dwc->eps[(num << 1) | 1];
 195                 int             mult = 1;
 196                 int             tmp;
 197
 198                 if (!(dep->flags & DWC3_EP_ENABLED))
 199                         continue;
 200
 201                 if (usb_endpoint_xfer_bulk(dep->endpoint.desc)
 202                                 || usb_endpoint_xfer_isoc(dep->endpoint.desc))
 203                         mult = 3;
 204
 205                 /*
 206                  * REVISIT: the following assumes we will always have enough
 207                  * space available on the FIFO RAM for all possible use cases.
 208                  * Make sure that's true somehow and change FIFO allocation
 209                  * accordingly.
 210                  *
 211                  * If we have Bulk or Isochronous endpoints, we want
 212                  * them to be able to be very, very fast. So we're giving
 213                  * those endpoints a fifo_size which is enough for 3 full
 214                  * packets
 215                  */
 216                 tmp = mult * (dep->endpoint.maxpacket + mdwidth);
 217                 tmp += mdwidth;
 218
 219                 fifo_size = DIV_ROUND_UP(tmp, mdwidth);
 220
 221                 fifo_size |= (last_fifo_depth << 16);
 222
 223                 dwc3_trace(trace_dwc3_gadget, "%s: Fifo Addr %04x Size %d",
 224                                 dep->name, last_fifo_depth, fifo_size & 0xffff);
 225
 226                 dwc3_writel(dwc->regs, DWC3_GTXFIFOSIZ(num), fifo_size);
 227
 228                 last_fifo_depth += (fifo_size & 0xffff);
 229         }
 230
 231         return 0;
 232 }
 233
 234 void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
 235                 int status)
 236 {
 237         struct dwc3                     *dwc = dep->dwc;
 238         int                             i;
 239
 240         if (req->queued) {
 241                 i = 0;
 242                 do {
 243                         dep->busy_slot++;
 244                         /*
 245                          * Skip LINK TRB. We can't use req->trb and check for
 246                          * DWC3_TRBCTL_LINK_TRB because it points the TRB we
 247                          * just completed (not the LINK TRB).
 248                          */
 249                         if (((dep->busy_slot & DWC3_TRB_MASK) ==
 250                                 DWC3_TRB_NUM- 1) &&
 251                                 usb_endpoint_xfer_isoc(dep->endpoint.desc))
 252                                 dep->busy_slot++;
 253                 } while(++i < req->request.num_mapped_sgs);
 254                 req->queued = false;
 255         }
 256         list_del(&req->list);
 257         req->trb = NULL;
 258
 259         if (req->request.status == -EINPROGRESS)
 260                 req->request.status = status;
 261
 262         if (dwc->ep0_bounced && dep->number == 0)
 263                 dwc->ep0_bounced = false;
 264         else
 265                 usb_gadget_unmap_request(&dwc->gadget, &req->request,
 266                                 req->direction);
 267
 268         trace_dwc3_gadget_giveback(req);
 269
 270         spin_unlock(&dwc->lock);
 271         usb_gadget_giveback_request(&dep->endpoint, &req->request);
 272         spin_lock(&dwc->lock);
 273 }
 274
 275 int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned cmd, u32 param)
 276 {
 277         u32             timeout = 500;
 278         u32             reg;
 279
 280         trace_dwc3_gadget_generic_cmd(cmd, param);
 281
 282         dwc3_writel(dwc->regs, DWC3_DGCMDPAR, param);
 283         dwc3_writel(dwc->regs, DWC3_DGCMD, cmd | DWC3_DGCMD_CMDACT);
 284
 285         do {
 286                 reg = dwc3_readl(dwc->regs, DWC3_DGCMD);
 287                 if (!(reg & DWC3_DGCMD_CMDACT)) {
 288                         dwc3_trace(trace_dwc3_gadget,
 289                                         "Command Complete --> %d",
 290                                         DWC3_DGCMD_STATUS(reg));
 291                         if (DWC3_DGCMD_STATUS(reg))
 292                                 return -EINVAL;
 293                         return 0;
 294                 }
 295
 296                 /*
 297                  * We can't sleep here, because it's also called from
 298                  * interrupt context.
 299                  */
 300                 timeout--;
 301                 if (!timeout) {
 302                         dwc3_trace(trace_dwc3_gadget,
 303                                         "Command Timed Out");
 304                         return -ETIMEDOUT;
 305                 }
 306                 udelay(1);
 307         } while (1);
 308 }
 309
 310 int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep,
 311                 unsigned cmd, struct dwc3_gadget_ep_cmd_params *params)
 312 {
 313         struct dwc3_ep          *dep = dwc->eps[ep];
 314         u32                     timeout = 500;
 315         u32                     reg;
 316
 317         trace_dwc3_gadget_ep_cmd(dep, cmd, params);
 318
 319         dwc3_writel(dwc->regs, DWC3_DEPCMDPAR0(ep), params->param0);
 320         dwc3_writel(dwc->regs, DWC3_DEPCMDPAR1(ep), params->param1);
 321         dwc3_writel(dwc->regs, DWC3_DEPCMDPAR2(ep), params->param2);
 322
 323         dwc3_writel(dwc->regs, DWC3_DEPCMD(ep), cmd | DWC3_DEPCMD_CMDACT);
 324         do {
 325                 reg = dwc3_readl(dwc->regs, DWC3_DEPCMD(ep));
 326                 if (!(reg & DWC3_DEPCMD_CMDACT)) {
 327                         dwc3_trace(trace_dwc3_gadget,
 328                                         "Command Complete --> %d",
 329                                         DWC3_DEPCMD_STATUS(reg));
 330                         if (DWC3_DEPCMD_STATUS(reg))
 331                                 return -EINVAL;
 332                         return 0;
 333                 }
 334
 335                 /*
 336                  * We can't sleep here, because it is also called from
 337                  * interrupt context.
 338                  */
 339                 timeout--;
 340                 if (!timeout) {
 341                         dwc3_trace(trace_dwc3_gadget,
 342                                         "Command Timed Out");
 343                         return -ETIMEDOUT;
 344                 }
 345
 346                 udelay(1);
 347         } while (1);
 348 }
 349
 350 static dma_addr_t dwc3_trb_dma_offset(struct dwc3_ep *dep,
 351                 struct dwc3_trb *trb)
 352 {
 353         u32             offset = (char *) trb - (char *) dep->trb_pool;
 354
 355         return dep->trb_pool_dma + offset;
 356 }
 357
 358 static int dwc3_alloc_trb_pool(struct dwc3_ep *dep)
 359 {
 360         struct dwc3             *dwc = dep->dwc;
 361
 362         if (dep->trb_pool)
 363                 return 0;
 364
 365         dep->trb_pool = dma_alloc_coherent(dwc->dev,
 366                         sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
 367                         &dep->trb_pool_dma, GFP_KERNEL);
 368         if (!dep->trb_pool) {
 369                 dev_err(dep->dwc->dev, "failed to allocate trb pool for %s\n",
 370                                 dep->name);
 371                 return -ENOMEM;
 372         }
 373
 374         return 0;
 375 }
 376
 377 static void dwc3_free_trb_pool(struct dwc3_ep *dep)
 378 {
 379         struct dwc3             *dwc = dep->dwc;
 380
 381         dma_free_coherent(dwc->dev, sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
 382                         dep->trb_pool, dep->trb_pool_dma);
 383
 384         dep->trb_pool = NULL;
 385         dep->trb_pool_dma = 0;
 386 }
 387
 388 static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep);
 389
 390 /**
 391  * dwc3_gadget_start_config - Configure EP resources
 392  * @dwc: pointer to our controller context structure
 393  * @dep: endpoint that is being enabled
 394  *
 395  * The assignment of transfer resources cannot perfectly follow the
 396  * data book due to the fact that the controller driver does not have
 397  * all knowledge of the configuration in advance. It is given this
 398  * information piecemeal by the composite gadget framework after every
 399  * SET_CONFIGURATION and SET_INTERFACE. Trying to follow the databook
 400  * programming model in this scenario can cause errors. For two
 401  * reasons:
 402  *
 403  * 1) The databook says to do DEPSTARTCFG for every SET_CONFIGURATION
 404  * and SET_INTERFACE (8.1.5). This is incorrect in the scenario of
 405  * multiple interfaces.
 406  *
 407  * 2) The databook does not mention doing more DEPXFERCFG for new
 408  * endpoint on alt setting (8.1.6).
 409  *
 410  * The following simplified method is used instead:
 411  *
 412  * All hardware endpoints can be assigned a transfer resource and this
 413  * setting will stay persistent until either a core reset or
 414  * hibernation. So whenever we do a DEPSTARTCFG(0) we can go ahead and
 415  * do DEPXFERCFG for every hardware endpoint as well. We are
 416  * guaranteed that there are as many transfer resources as endpoints.
 417  *
 418  * This function is called for each endpoint when it is being enabled
 419  * but is triggered only when called for EP0-out, which always happens
 420  * first, and which should only happen in one of the above conditions.
 421  */
 422 static int dwc3_gadget_start_config(struct dwc3 *dwc, struct dwc3_ep *dep)
 423 {
 424         struct dwc3_gadget_ep_cmd_params params;
 425         u32                     cmd;
 426         int                     i;
 427         int                     ret;
 428
 429         if (dep->number)
 430                 return 0;
 431
 432         memset(&params, 0x00, sizeof(params));
 433         cmd = DWC3_DEPCMD_DEPSTARTCFG;
 434
 435         ret = dwc3_send_gadget_ep_cmd(dwc, 0, cmd, &params);
 436         if (ret)
 437                 return ret;
 438
 439         for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
 440                 struct dwc3_ep *dep = dwc->eps[i];
 441
 442                 if (!dep)
 443                         continue;
 444
 445                 ret = dwc3_gadget_set_xfer_resource(dwc, dep);
 446                 if (ret)
 447                         return ret;
 448         }
 449
 450         return 0;
 451 }
 452
 453 static int dwc3_gadget_set_ep_config(struct dwc3 *dwc, struct dwc3_ep *dep,
 454                 const struct usb_endpoint_descriptor *desc,
 455                 const struct usb_ss_ep_comp_descriptor *comp_desc,
 456                 bool ignore, bool restore)
 457 {
 458         struct dwc3_gadget_ep_cmd_params params;
 459
 460         memset(&params, 0x00, sizeof(params));
 461
 462         params.param0 = DWC3_DEPCFG_EP_TYPE(usb_endpoint_type(desc))
 463                 | DWC3_DEPCFG_MAX_PACKET_SIZE(usb_endpoint_maxp(desc));
 464
 465         /* Burst size is only needed in SuperSpeed mode */
 466         if (dwc->gadget.speed >= USB_SPEED_SUPER) {
 467                 u32 burst = dep->endpoint.maxburst - 1;
 468
 469                 params.param0 |= DWC3_DEPCFG_BURST_SIZE(burst);
 470         }
 471
 472         if (ignore)
 473                 params.param0 |= DWC3_DEPCFG_IGN_SEQ_NUM;
 474
 475         if (restore) {
 476                 params.param0 |= DWC3_DEPCFG_ACTION_RESTORE;
 477                 params.param2 |= dep->saved_state;
 478         }
 479
 480         params.param1 = DWC3_DEPCFG_XFER_COMPLETE_EN
 481                 | DWC3_DEPCFG_XFER_NOT_READY_EN;
 482
 483         if (usb_ss_max_streams(comp_desc) && usb_endpoint_xfer_bulk(desc)) {
 484                 params.param1 |= DWC3_DEPCFG_STREAM_CAPABLE
 485                         | DWC3_DEPCFG_STREAM_EVENT_EN;
 486                 dep->stream_capable = true;
 487         }
 488
 489         if (!usb_endpoint_xfer_control(desc))
 490                 params.param1 |= DWC3_DEPCFG_XFER_IN_PROGRESS_EN;
 491
 492         /*
 493          * We are doing 1:1 mapping for endpoints, meaning
 494          * Physical Endpoints 2 maps to Logical Endpoint 2 and
 495          * so on. We consider the direction bit as part of the physical
 496          * endpoint number. So USB endpoint 0x81 is 0x03.
 497          */
 498         params.param1 |= DWC3_DEPCFG_EP_NUMBER(dep->number);
 499
 500         /*
 501          * We must use the lower 16 TX FIFOs even though
 502          * HW might have more
 503          */
 504         if (dep->direction)
 505                 params.param0 |= DWC3_DEPCFG_FIFO_NUMBER(dep->number >> 1);
 506
 507         if (desc->bInterval) {
 508                 params.param1 |= DWC3_DEPCFG_BINTERVAL_M1(desc->bInterval - 1);
 509                 dep->interval = 1 << (desc->bInterval - 1);
 510         }
 511
 512         return dwc3_send_gadget_ep_cmd(dwc, dep->number,
 513                         DWC3_DEPCMD_SETEPCONFIG, &params);
 514 }
 515
 516 static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep)
 517 {
 518         struct dwc3_gadget_ep_cmd_params params;
 519
 520         memset(&params, 0x00, sizeof(params));
 521
 522         params.param0 = DWC3_DEPXFERCFG_NUM_XFER_RES(1);
 523
 524         return dwc3_send_gadget_ep_cmd(dwc, dep->number,
 525                         DWC3_DEPCMD_SETTRANSFRESOURCE, &params);
 526 }
 527
 528 /**
 529  * __dwc3_gadget_ep_enable - Initializes a HW endpoint
 530  * @dep: endpoint to be initialized
 531  * @desc: USB Endpoint Descriptor
 532  *
 533  * Caller should take care of locking
 534  */
 535 static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep,
 536                 const struct usb_endpoint_descriptor *desc,
 537                 const struct usb_ss_ep_comp_descriptor *comp_desc,
 538                 bool ignore, bool restore)
 539 {
 540         struct dwc3             *dwc = dep->dwc;
 541         u32                     reg;
 542         int                     ret;
 543
 544         dwc3_trace(trace_dwc3_gadget, "Enabling %s", dep->name);
 545
 546         if (!(dep->flags & DWC3_EP_ENABLED)) {
 547                 ret = dwc3_gadget_start_config(dwc, dep);
 548                 if (ret)
 549                         return ret;
 550         }
 551
 552         ret = dwc3_gadget_set_ep_config(dwc, dep, desc, comp_desc, ignore,
 553                         restore);
 554         if (ret)
 555                 return ret;
 556
 557         if (!(dep->flags & DWC3_EP_ENABLED)) {
 558                 struct dwc3_trb *trb_st_hw;
 559                 struct dwc3_trb *trb_link;
 560
 561                 dep->endpoint.desc = desc;
 562                 dep->comp_desc = comp_desc;
 563                 dep->type = usb_endpoint_type(desc);
 564                 dep->flags |= DWC3_EP_ENABLED;
 565
 566                 reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
 567                 reg |= DWC3_DALEPENA_EP(dep->number);
 568                 dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
 569
 570                 if (!usb_endpoint_xfer_isoc(desc))
 571                         goto out;
 572
 573                 /* Link TRB for ISOC. The HWO bit is never reset */
 574                 trb_st_hw = &dep->trb_pool[0];
 575
 576                 trb_link = &dep->trb_pool[DWC3_TRB_NUM - 1];
 577                 memset(trb_link, 0, sizeof(*trb_link));
 578
 579                 trb_link->bpl = lower_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
 580                 trb_link->bph = upper_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
 581                 trb_link->ctrl |= DWC3_TRBCTL_LINK_TRB;
 582                 trb_link->ctrl |= DWC3_TRB_CTRL_HWO;
 583         }
 584
 585 out:
 586         switch (usb_endpoint_type(desc)) {
 587         case USB_ENDPOINT_XFER_CONTROL:
 588                 /* don't change name */
 589                 break;
 590         case USB_ENDPOINT_XFER_ISOC:
 591                 strlcat(dep->name, "-isoc", sizeof(dep->name));
 592                 break;
 593         case USB_ENDPOINT_XFER_BULK:
 594                 strlcat(dep->name, "-bulk", sizeof(dep->name));
 595                 break;
 596         case USB_ENDPOINT_XFER_INT:
 597                 strlcat(dep->name, "-int", sizeof(dep->name));
 598                 break;
 599         default:
 600                 dev_err(dwc->dev, "invalid endpoint transfer type\n");
 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         if (!list_empty(&dep->req_queued)) {
 612                 dwc3_stop_active_transfer(dwc, dep->number, true);
 613
 614                 /* - giveback all requests to gadget driver */
 615                 while (!list_empty(&dep->req_queued)) {
 616                         req = next_request(&dep->req_queued);
 617
 618                         dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
 619                 }
 620         }
 621
 622         while (!list_empty(&dep->request_list)) {
 623                 req = next_request(&dep->request_list);
 624
 625                 dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
 626         }
 627 }
 628
 629 /**
 630  * __dwc3_gadget_ep_disable - Disables a HW endpoint
 631  * @dep: the endpoint to disable
 632  *
 633  * This function also removes requests which are currently processed ny the
 634  * hardware and those which are not yet scheduled.
 635  * Caller should take care of locking.
 636  */
 637 static int __dwc3_gadget_ep_disable(struct dwc3_ep *dep)
 638 {
 639         struct dwc3             *dwc = dep->dwc;
 640         u32                     reg;
 641
 642         dwc3_trace(trace_dwc3_gadget, "Disabling %s", dep->name);
 643
 644         dwc3_remove_requests(dwc, dep);
 645
 646         /* make sure HW endpoint isn't stalled */
 647         if (dep->flags & DWC3_EP_STALL)
 648                 __dwc3_gadget_ep_set_halt(dep, 0, false);
 649
 650         reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
 651         reg &= ~DWC3_DALEPENA_EP(dep->number);
 652         dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
 653
 654         dep->stream_capable = false;
 655         dep->endpoint.desc = NULL;
 656         dep->comp_desc = NULL;
 657         dep->type = 0;
 658         dep->flags = 0;
 659
 660         snprintf(dep->name, sizeof(dep->name), "ep%d%s",
 661                         dep->number >> 1,
 662                         (dep->number & 1) ? "in" : "out");
 663
 664         return 0;
 665 }
 666
 667 /* -------------------------------------------------------------------------- */
 668
 669 static int dwc3_gadget_ep0_enable(struct usb_ep *ep,
 670                 const struct usb_endpoint_descriptor *desc)
 671 {
 672         return -EINVAL;
 673 }
 674
 675 static int dwc3_gadget_ep0_disable(struct usb_ep *ep)
 676 {
 677         return -EINVAL;
 678 }
 679
 680 /* -------------------------------------------------------------------------- */
 681
 682 static int dwc3_gadget_ep_enable(struct usb_ep *ep,
 683                 const struct usb_endpoint_descriptor *desc)
 684 {
 685         struct dwc3_ep                  *dep;
 686         struct dwc3                     *dwc;
 687         unsigned long                   flags;
 688         int                             ret;
 689
 690         if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
 691                 pr_debug("dwc3: invalid parameters\n");
 692                 return -EINVAL;
 693         }
 694
 695         if (!desc->wMaxPacketSize) {
 696                 pr_debug("dwc3: missing wMaxPacketSize\n");
 697                 return -EINVAL;
 698         }
 699
 700         dep = to_dwc3_ep(ep);
 701         dwc = dep->dwc;
 702
 703         if (dev_WARN_ONCE(dwc->dev, dep->flags & DWC3_EP_ENABLED,
 704                                         "%s is already enabled\n",
 705                                         dep->name))
 706                 return 0;
 707
 708         spin_lock_irqsave(&dwc->lock, flags);
 709         ret = __dwc3_gadget_ep_enable(dep, desc, ep->comp_desc, false, false);
 710         spin_unlock_irqrestore(&dwc->lock, flags);
 711
 712         return ret;
 713 }
 714
 715 static int dwc3_gadget_ep_disable(struct usb_ep *ep)
 716 {
 717         struct dwc3_ep                  *dep;
 718         struct dwc3                     *dwc;
 719         unsigned long                   flags;
 720         int                             ret;
 721
 722         if (!ep) {
 723                 pr_debug("dwc3: invalid parameters\n");
 724                 return -EINVAL;
 725         }
 726
 727         dep = to_dwc3_ep(ep);
 728         dwc = dep->dwc;
 729
 730         if (dev_WARN_ONCE(dwc->dev, !(dep->flags & DWC3_EP_ENABLED),
 731                                         "%s is already disabled\n",
 732                                         dep->name))
 733                 return 0;
 734
 735         spin_lock_irqsave(&dwc->lock, flags);
 736         ret = __dwc3_gadget_ep_disable(dep);
 737         spin_unlock_irqrestore(&dwc->lock, flags);
 738
 739         return ret;
 740 }
 741
 742 static struct usb_request *dwc3_gadget_ep_alloc_request(struct usb_ep *ep,
 743         gfp_t gfp_flags)
 744 {
 745         struct dwc3_request             *req;
 746         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
 747
 748         req = kzalloc(sizeof(*req), gfp_flags);
 749         if (!req)
 750                 return NULL;
 751
 752         req->epnum      = dep->number;
 753         req->dep        = dep;
 754
 755         trace_dwc3_alloc_request(req);
 756
 757         return &req->request;
 758 }
 759
 760 static void dwc3_gadget_ep_free_request(struct usb_ep *ep,
 761                 struct usb_request *request)
 762 {
 763         struct dwc3_request             *req = to_dwc3_request(request);
 764
 765         trace_dwc3_free_request(req);
 766         kfree(req);
 767 }
 768
 769 /**
 770  * dwc3_prepare_one_trb - setup one TRB from one request
 771  * @dep: endpoint for which this request is prepared
 772  * @req: dwc3_request pointer
 773  */
 774 static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
 775                 struct dwc3_request *req, dma_addr_t dma,
 776                 unsigned length, unsigned last, unsigned chain, unsigned node)
 777 {
 778         struct dwc3_trb         *trb;
 779
 780         dwc3_trace(trace_dwc3_gadget, "%s: req %p dma %08llx length %d%s%s",
 781                         dep->name, req, (unsigned long long) dma,
 782                         length, last ? " last" : "",
 783                         chain ? " chain" : "");
 784
 785
 786         trb = &dep->trb_pool[dep->free_slot & DWC3_TRB_MASK];
 787
 788         if (!req->trb) {
 789                 dwc3_gadget_move_request_queued(req);
 790                 req->trb = trb;
 791                 req->trb_dma = dwc3_trb_dma_offset(dep, trb);
 792                 req->start_slot = dep->free_slot & DWC3_TRB_MASK;
 793         }
 794
 795         dep->free_slot++;
 796         /* Skip the LINK-TRB on ISOC */
 797         if (((dep->free_slot & DWC3_TRB_MASK) == DWC3_TRB_NUM - 1) &&
 798                         usb_endpoint_xfer_isoc(dep->endpoint.desc))
 799                 dep->free_slot++;
 800
 801         trb->size = DWC3_TRB_SIZE_LENGTH(length);
 802         trb->bpl = lower_32_bits(dma);
 803         trb->bph = upper_32_bits(dma);
 804
 805         switch (usb_endpoint_type(dep->endpoint.desc)) {
 806         case USB_ENDPOINT_XFER_CONTROL:
 807                 trb->ctrl = DWC3_TRBCTL_CONTROL_SETUP;
 808                 break;
 809
 810         case USB_ENDPOINT_XFER_ISOC:
 811                 if (!node)
 812                         trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;
 813                 else
 814                         trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS;
 815                 break;
 816
 817         case USB_ENDPOINT_XFER_BULK:
 818         case USB_ENDPOINT_XFER_INT:
 819                 trb->ctrl = DWC3_TRBCTL_NORMAL;
 820                 break;
 821         default:
 822                 /*
 823                  * This is only possible with faulty memory because we
 824                  * checked it already :)
 825                  */
 826                 BUG();
 827         }
 828
 829         if (!req->request.no_interrupt && !chain)
 830                 trb->ctrl |= DWC3_TRB_CTRL_IOC;
 831
 832         if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
 833                 trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
 834                 trb->ctrl |= DWC3_TRB_CTRL_CSP;
 835         } else if (last) {
 836                 trb->ctrl |= DWC3_TRB_CTRL_LST;
 837         }
 838
 839         if (chain)
 840                 trb->ctrl |= DWC3_TRB_CTRL_CHN;
 841
 842         if (usb_endpoint_xfer_bulk(dep->endpoint.desc) && dep->stream_capable)
 843                 trb->ctrl |= DWC3_TRB_CTRL_SID_SOFN(req->request.stream_id);
 844
 845         trb->ctrl |= DWC3_TRB_CTRL_HWO;
 846
 847         trace_dwc3_prepare_trb(dep, trb);
 848 }
 849
 850 /*
 851  * dwc3_prepare_trbs - setup TRBs from requests
 852  * @dep: endpoint for which requests are being prepared
 853  * @starting: true if the endpoint is idle and no requests are queued.
 854  *
 855  * The function goes through the requests list and sets up TRBs for the
 856  * transfers. The function returns once there are no more TRBs available or
 857  * it runs out of requests.
 858  */
 859 static void dwc3_prepare_trbs(struct dwc3_ep *dep, bool starting)
 860 {
 861         struct dwc3_request     *req, *n;
 862         u32                     trbs_left;
 863         u32                     max;
 864         unsigned int            last_one = 0;
 865
 866         BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);
 867
 868         /* the first request must not be queued */
 869         trbs_left = (dep->busy_slot - dep->free_slot) & DWC3_TRB_MASK;
 870
 871         /* Can't wrap around on a non-isoc EP since there's no link TRB */
 872         if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
 873                 max = DWC3_TRB_NUM - (dep->free_slot & DWC3_TRB_MASK);
 874                 if (trbs_left > max)
 875                         trbs_left = max;
 876         }
 877
 878         /*
 879          * If busy & slot are equal than it is either full or empty. If we are
 880          * starting to process requests then we are empty. Otherwise we are
 881          * full and don't do anything
 882          */
 883         if (!trbs_left) {
 884                 if (!starting)
 885                         return;
 886                 trbs_left = DWC3_TRB_NUM;
 887                 /*
 888                  * In case we start from scratch, we queue the ISOC requests
 889                  * starting from slot 1. This is done because we use ring
 890                  * buffer and have no LST bit to stop us. Instead, we place
 891                  * IOC bit every TRB_NUM/4. We try to avoid having an interrupt
 892                  * after the first request so we start at slot 1 and have
 893                  * 7 requests proceed before we hit the first IOC.
 894                  * Other transfer types don't use the ring buffer and are
 895                  * processed from the first TRB until the last one. Since we
 896                  * don't wrap around we have to start at the beginning.
 897                  */
 898                 if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
 899                         dep->busy_slot = 1;
 900                         dep->free_slot = 1;
 901                 } else {
 902                         dep->busy_slot = 0;
 903                         dep->free_slot = 0;
 904                 }
 905         }
 906
 907         /* The last TRB is a link TRB, not used for xfer */
 908         if ((trbs_left <= 1) && usb_endpoint_xfer_isoc(dep->endpoint.desc))
 909                 return;
 910
 911         list_for_each_entry_safe(req, n, &dep->request_list, list) {
 912                 unsigned        length;
 913                 dma_addr_t      dma;
 914                 last_one = false;
 915
 916                 if (req->request.num_mapped_sgs > 0) {
 917                         struct usb_request *request = &req->request;
 918                         struct scatterlist *sg = request->sg;
 919                         struct scatterlist *s;
 920                         int             i;
 921
 922                         for_each_sg(sg, s, request->num_mapped_sgs, i) {
 923                                 unsigned chain = true;
 924
 925                                 length = sg_dma_len(s);
 926                                 dma = sg_dma_address(s);
 927
 928                                 if (i == (request->num_mapped_sgs - 1) ||
 929                                                 sg_is_last(s)) {
 930                                         if (list_empty(&dep->request_list))
 931                                                 last_one = true;
 932                                         chain = false;
 933                                 }
 934
 935                                 trbs_left--;
 936                                 if (!trbs_left)
 937                                         last_one = true;
 938
 939                                 if (last_one)
 940                                         chain = false;
 941
 942                                 dwc3_prepare_one_trb(dep, req, dma, length,
 943                                                 last_one, chain, i);
 944
 945                                 if (last_one)
 946                                         break;
 947                         }
 948
 949                         if (last_one)
 950                                 break;
 951                 } else {
 952                         dma = req->request.dma;
 953                         length = req->request.length;
 954                         trbs_left--;
 955
 956                         if (!trbs_left)
 957                                 last_one = 1;
 958
 959                         /* Is this the last request? */
 960                         if (list_is_last(&req->list, &dep->request_list))
 961                                 last_one = 1;
 962
 963                         dwc3_prepare_one_trb(dep, req, dma, length,
 964                                         last_one, false, 0);
 965
 966                         if (last_one)
 967                                 break;
 968                 }
 969         }
 970 }
 971
 972 static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep, u16 cmd_param,
 973                 int start_new)
 974 {
 975         struct dwc3_gadget_ep_cmd_params params;
 976         struct dwc3_request             *req;
 977         struct dwc3                     *dwc = dep->dwc;
 978         int                             ret;
 979         u32                             cmd;
 980
 981         if (start_new && (dep->flags & DWC3_EP_BUSY)) {
 982                 dwc3_trace(trace_dwc3_gadget, "%s: endpoint busy", dep->name);
 983                 return -EBUSY;
 984         }
 985
 986         /*
 987          * If we are getting here after a short-out-packet we don't enqueue any
 988          * new requests as we try to set the IOC bit only on the last request.
 989          */
 990         if (start_new) {
 991                 if (list_empty(&dep->req_queued))
 992                         dwc3_prepare_trbs(dep, start_new);
 993
 994                 /* req points to the first request which will be sent */
 995                 req = next_request(&dep->req_queued);
 996         } else {
 997                 dwc3_prepare_trbs(dep, start_new);
 998
 999                 /*
1000                  * req points to the first request where HWO changed from 0 to 1
1001                  */
1002                 req = next_request(&dep->req_queued);
1003         }
1004         if (!req) {
1005                 dep->flags |= DWC3_EP_PENDING_REQUEST;
1006                 return 0;
1007         }
1008
1009         memset(&params, 0, sizeof(params));
1010
1011         if (start_new) {
1012                 params.param0 = upper_32_bits(req->trb_dma);
1013                 params.param1 = lower_32_bits(req->trb_dma);
1014                 cmd = DWC3_DEPCMD_STARTTRANSFER;
1015         } else {
1016                 cmd = DWC3_DEPCMD_UPDATETRANSFER;
1017         }
1018
1019         cmd |= DWC3_DEPCMD_PARAM(cmd_param);
1020         ret = dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, &params);
1021         if (ret < 0) {
1022                 /*
1023                  * FIXME we need to iterate over the list of requests
1024                  * here and stop, unmap, free and del each of the linked
1025                  * requests instead of what we do now.
1026                  */
1027                 usb_gadget_unmap_request(&dwc->gadget, &req->request,
1028                                 req->direction);
1029                 list_del(&req->list);
1030                 return ret;
1031         }
1032
1033         dep->flags |= DWC3_EP_BUSY;
1034
1035         if (start_new) {
1036                 dep->resource_index = dwc3_gadget_ep_get_transfer_index(dwc,
1037                                 dep->number);
1038                 WARN_ON_ONCE(!dep->resource_index);
1039         }
1040
1041         return 0;
1042 }
1043
1044 static void __dwc3_gadget_start_isoc(struct dwc3 *dwc,
1045                 struct dwc3_ep *dep, u32 cur_uf)
1046 {
1047         u32 uf;
1048
1049         if (list_empty(&dep->request_list)) {
1050                 dwc3_trace(trace_dwc3_gadget,
1051                                 "ISOC ep %s run out for requests",
1052                                 dep->name);
1053                 dep->flags |= DWC3_EP_PENDING_REQUEST;
1054                 return;
1055         }
1056
1057         /* 4 micro frames in the future */
1058         uf = cur_uf + dep->interval * 4;
1059
1060         __dwc3_gadget_kick_transfer(dep, uf, 1);
1061 }
1062
1063 static void dwc3_gadget_start_isoc(struct dwc3 *dwc,
1064                 struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
1065 {
1066         u32 cur_uf, mask;
1067
1068         mask = ~(dep->interval - 1);
1069         cur_uf = event->parameters & mask;
1070
1071         __dwc3_gadget_start_isoc(dwc, dep, cur_uf);
1072 }
1073
1074 static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
1075 {
1076         struct dwc3             *dwc = dep->dwc;
1077         int                     ret;
1078
1079         if (!dep->endpoint.desc) {
1080                 dwc3_trace(trace_dwc3_gadget,
1081                                 "trying to queue request %p to disabled %s\n",
1082                                 &req->request, dep->endpoint.name);
1083                 return -ESHUTDOWN;
1084         }
1085
1086         if (WARN(req->dep != dep, "request %p belongs to '%s'\n",
1087                                 &req->request, req->dep->name)) {
1088                 dwc3_trace(trace_dwc3_gadget, "request %p belongs to '%s'\n",
1089                                 &req->request, req->dep->name);
1090                 return -EINVAL;
1091         }
1092
1093         req->request.actual     = 0;
1094         req->request.status     = -EINPROGRESS;
1095         req->direction          = dep->direction;
1096         req->epnum              = dep->number;
1097
1098         trace_dwc3_ep_queue(req);
1099
1100         /*
1101          * We only add to our list of requests now and
1102          * start consuming the list once we get XferNotReady
1103          * IRQ.
1104          *
1105          * That way, we avoid doing anything that we don't need
1106          * to do now and defer it until the point we receive a
1107          * particular token from the Host side.
1108          *
1109          * This will also avoid Host cancelling URBs due to too
1110          * many NAKs.
1111          */
1112         ret = usb_gadget_map_request(&dwc->gadget, &req->request,
1113                         dep->direction);
1114         if (ret)
1115                 return ret;
1116
1117         list_add_tail(&req->list, &dep->request_list);
1118
1119         /*
1120          * If there are no pending requests and the endpoint isn't already
1121          * busy, we will just start the request straight away.
1122          *
1123          * This will save one IRQ (XFER_NOT_READY) and possibly make it a
1124          * little bit faster.
1125          */
1126         if (!usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
1127                         !usb_endpoint_xfer_int(dep->endpoint.desc) &&
1128                         !(dep->flags & DWC3_EP_BUSY)) {
1129                 ret = __dwc3_gadget_kick_transfer(dep, 0, true);
1130                 goto out;
1131         }
1132
1133         /*
1134          * There are a few special cases:
1135          *
1136          * 1. XferNotReady with empty list of requests. We need to kick the
1137          *    transfer here in that situation, otherwise we will be NAKing
1138          *    forever. If we get XferNotReady before gadget driver has a
1139          *    chance to queue a request, we will ACK the IRQ but won't be
1140          *    able to receive the data until the next request is queued.
1141          *    The following code is handling exactly that.
1142          *
1143          */
1144         if (dep->flags & DWC3_EP_PENDING_REQUEST) {
1145                 /*
1146                  * If xfernotready is already elapsed and it is a case
1147                  * of isoc transfer, then issue END TRANSFER, so that
1148                  * you can receive xfernotready again and can have
1149                  * notion of current microframe.
1150                  */
1151                 if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1152                         if (list_empty(&dep->req_queued)) {
1153                                 dwc3_stop_active_transfer(dwc, dep->number, true);
1154                                 dep->flags = DWC3_EP_ENABLED;
1155                         }
1156                         return 0;
1157                 }
1158
1159                 ret = __dwc3_gadget_kick_transfer(dep, 0, true);
1160                 if (!ret)
1161                         dep->flags &= ~DWC3_EP_PENDING_REQUEST;
1162
1163                 goto out;
1164         }
1165
1166         /*
1167          * 2. XferInProgress on Isoc EP with an active transfer. We need to
1168          *    kick the transfer here after queuing a request, otherwise the
1169          *    core may not see the modified TRB(s).
1170          */
1171         if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
1172                         (dep->flags & DWC3_EP_BUSY) &&
1173                         !(dep->flags & DWC3_EP_MISSED_ISOC)) {
1174                 WARN_ON_ONCE(!dep->resource_index);
1175                 ret = __dwc3_gadget_kick_transfer(dep, dep->resource_index,
1176                                 false);
1177                 goto out;
1178         }
1179
1180         /*
1181          * 4. Stream Capable Bulk Endpoints. We need to start the transfer
1182          * right away, otherwise host will not know we have streams to be
1183          * handled.
1184          */
1185         if (dep->stream_capable)
1186                 ret = __dwc3_gadget_kick_transfer(dep, 0, true);
1187
1188 out:
1189         if (ret && ret != -EBUSY)
1190                 dwc3_trace(trace_dwc3_gadget,
1191                                 "%s: failed to kick transfers\n",
1192                                 dep->name);
1193         if (ret == -EBUSY)
1194                 ret = 0;
1195
1196         return ret;
1197 }
1198
1199 static void __dwc3_gadget_ep_zlp_complete(struct usb_ep *ep,
1200                 struct usb_request *request)
1201 {
1202         dwc3_gadget_ep_free_request(ep, request);
1203 }
1204
1205 static int __dwc3_gadget_ep_queue_zlp(struct dwc3 *dwc, struct dwc3_ep *dep)
1206 {
1207         struct dwc3_request             *req;
1208         struct usb_request              *request;
1209         struct usb_ep                   *ep = &dep->endpoint;
1210
1211         dwc3_trace(trace_dwc3_gadget, "queueing ZLP\n");
1212         request = dwc3_gadget_ep_alloc_request(ep, GFP_ATOMIC);
1213         if (!request)
1214                 return -ENOMEM;
1215
1216         request->length = 0;
1217         request->buf = dwc->zlp_buf;
1218         request->complete = __dwc3_gadget_ep_zlp_complete;
1219
1220         req = to_dwc3_request(request);
1221
1222         return __dwc3_gadget_ep_queue(dep, req);
1223 }
1224
1225 static int dwc3_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
1226         gfp_t gfp_flags)
1227 {
1228         struct dwc3_request             *req = to_dwc3_request(request);
1229         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1230         struct dwc3                     *dwc = dep->dwc;
1231
1232         unsigned long                   flags;
1233
1234         int                             ret;
1235
1236         spin_lock_irqsave(&dwc->lock, flags);
1237         ret = __dwc3_gadget_ep_queue(dep, req);
1238
1239         /*
1240          * Okay, here's the thing, if gadget driver has requested for a ZLP by
1241          * setting request->zero, instead of doing magic, we will just queue an
1242          * extra usb_request ourselves so that it gets handled the same way as
1243          * any other request.
1244          */
1245         if (ret == 0 && request->zero && request->length &&
1246             (request->length % ep->maxpacket == 0))
1247                 ret = __dwc3_gadget_ep_queue_zlp(dwc, dep);
1248
1249         spin_unlock_irqrestore(&dwc->lock, flags);
1250
1251         return ret;
1252 }
1253
1254 static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
1255                 struct usb_request *request)
1256 {
1257         struct dwc3_request             *req = to_dwc3_request(request);
1258         struct dwc3_request             *r = NULL;
1259
1260         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1261         struct dwc3                     *dwc = dep->dwc;
1262
1263         unsigned long                   flags;
1264         int                             ret = 0;
1265
1266         trace_dwc3_ep_dequeue(req);
1267
1268         spin_lock_irqsave(&dwc->lock, flags);
1269
1270         list_for_each_entry(r, &dep->request_list, list) {
1271                 if (r == req)
1272                         break;
1273         }
1274
1275         if (r != req) {
1276                 list_for_each_entry(r, &dep->req_queued, list) {
1277                         if (r == req)
1278                                 break;
1279                 }
1280                 if (r == req) {
1281                         /* wait until it is processed */
1282                         dwc3_stop_active_transfer(dwc, dep->number, true);
1283                         goto out1;
1284                 }
1285                 dev_err(dwc->dev, "request %p was not queued to %s\n",
1286                                 request, ep->name);
1287                 ret = -EINVAL;
1288                 goto out0;
1289         }
1290
1291 out1:
1292         /* giveback the request */
1293         dwc3_gadget_giveback(dep, req, -ECONNRESET);
1294
1295 out0:
1296         spin_unlock_irqrestore(&dwc->lock, flags);
1297
1298         return ret;
1299 }
1300
1301 int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
1302 {
1303         struct dwc3_gadget_ep_cmd_params        params;
1304         struct dwc3                             *dwc = dep->dwc;
1305         int                                     ret;
1306
1307         if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1308                 dev_err(dwc->dev, "%s is of Isochronous type\n", dep->name);
1309                 return -EINVAL;
1310         }
1311
1312         memset(&params, 0x00, sizeof(params));
1313
1314         if (value) {
1315                 if (!protocol && ((dep->direction && dep->flags & DWC3_EP_BUSY) ||
1316                                 (!list_empty(&dep->req_queued) ||
1317                                  !list_empty(&dep->request_list)))) {
1318                         dwc3_trace(trace_dwc3_gadget,
1319                                         "%s: pending request, cannot halt\n",
1320                                         dep->name);
1321                         return -EAGAIN;
1322                 }
1323
1324                 ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
1325                         DWC3_DEPCMD_SETSTALL, &params);
1326                 if (ret)
1327                         dev_err(dwc->dev, "failed to set STALL on %s\n",
1328                                         dep->name);
1329                 else
1330                         dep->flags |= DWC3_EP_STALL;
1331         } else {
1332                 ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
1333                         DWC3_DEPCMD_CLEARSTALL, &params);
1334                 if (ret)
1335                         dev_err(dwc->dev, "failed to clear STALL on %s\n",
1336                                         dep->name);
1337                 else
1338                         dep->flags &= ~(DWC3_EP_STALL | DWC3_EP_WEDGE);
1339         }
1340
1341         return ret;
1342 }
1343
1344 static int dwc3_gadget_ep_set_halt(struct usb_ep *ep, int value)
1345 {
1346         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1347         struct dwc3                     *dwc = dep->dwc;
1348
1349         unsigned long                   flags;
1350
1351         int                             ret;
1352
1353         spin_lock_irqsave(&dwc->lock, flags);
1354         ret = __dwc3_gadget_ep_set_halt(dep, value, false);
1355         spin_unlock_irqrestore(&dwc->lock, flags);
1356
1357         return ret;
1358 }
1359
1360 static int dwc3_gadget_ep_set_wedge(struct usb_ep *ep)
1361 {
1362         struct dwc3_ep                  *dep = to_dwc3_ep(ep);
1363         struct dwc3                     *dwc = dep->dwc;
1364         unsigned long                   flags;
1365         int                             ret;
1366
1367         spin_lock_irqsave(&dwc->lock, flags);
1368         dep->flags |= DWC3_EP_WEDGE;
1369
1370         if (dep->number == 0 || dep->number == 1)
1371                 ret = __dwc3_gadget_ep0_set_halt(ep, 1);
1372         else
1373                 ret = __dwc3_gadget_ep_set_halt(dep, 1, false);
1374         spin_unlock_irqrestore(&dwc->lock, flags);
1375
1376         return ret;
1377 }
1378
1379 /* -------------------------------------------------------------------------- */
1380
1381 static struct usb_endpoint_descriptor dwc3_gadget_ep0_desc = {
1382         .bLength        = USB_DT_ENDPOINT_SIZE,
1383         .bDescriptorType = USB_DT_ENDPOINT,
1384         .bmAttributes   = USB_ENDPOINT_XFER_CONTROL,
1385 };
1386
1387 static const struct usb_ep_ops dwc3_gadget_ep0_ops = {
1388         .enable         = dwc3_gadget_ep0_enable,
1389         .disable        = dwc3_gadget_ep0_disable,
1390         .alloc_request  = dwc3_gadget_ep_alloc_request,
1391         .free_request   = dwc3_gadget_ep_free_request,
1392         .queue          = dwc3_gadget_ep0_queue,
1393         .dequeue        = dwc3_gadget_ep_dequeue,
1394         .set_halt       = dwc3_gadget_ep0_set_halt,
1395         .set_wedge      = dwc3_gadget_ep_set_wedge,
1396 };
1397
1398 static const struct usb_ep_ops dwc3_gadget_ep_ops = {
1399         .enable         = dwc3_gadget_ep_enable,
1400         .disable        = dwc3_gadget_ep_disable,
1401         .alloc_request  = dwc3_gadget_ep_alloc_request,
1402         .free_request   = dwc3_gadget_ep_free_request,
1403         .queue          = dwc3_gadget_ep_queue,
1404         .dequeue        = dwc3_gadget_ep_dequeue,
1405         .set_halt       = dwc3_gadget_ep_set_halt,
1406         .set_wedge      = dwc3_gadget_ep_set_wedge,
1407 };
1408
1409 /* -------------------------------------------------------------------------- */
1410
1411 static int dwc3_gadget_get_frame(struct usb_gadget *g)
1412 {
1413         struct dwc3             *dwc = gadget_to_dwc(g);
1414         u32                     reg;
1415
1416         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1417         return DWC3_DSTS_SOFFN(reg);
1418 }
1419
1420 static int dwc3_gadget_wakeup(struct usb_gadget *g)
1421 {
1422         struct dwc3             *dwc = gadget_to_dwc(g);
1423
1424         unsigned long           timeout;
1425         unsigned long           flags;
1426
1427         u32                     reg;
1428
1429         int                     ret = 0;
1430
1431         u8                      link_state;
1432         u8                      speed;
1433
1434         spin_lock_irqsave(&dwc->lock, flags);
1435
1436         /*
1437          * According to the Databook Remote wakeup request should
1438          * be issued only when the device is in early suspend state.
1439          *
1440          * We can check that via USB Link State bits in DSTS register.
1441          */
1442         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1443
1444         speed = reg & DWC3_DSTS_CONNECTSPD;
1445         if ((speed == DWC3_DSTS_SUPERSPEED) ||
1446             (speed == DWC3_DSTS_SUPERSPEED_PLUS)) {
1447                 dwc3_trace(trace_dwc3_gadget, "no wakeup on SuperSpeed\n");
1448                 ret = -EINVAL;
1449                 goto out;
1450         }
1451
1452         link_state = DWC3_DSTS_USBLNKST(reg);
1453
1454         switch (link_state) {
1455         case DWC3_LINK_STATE_RX_DET:    /* in HS, means Early Suspend */
1456         case DWC3_LINK_STATE_U3:        /* in HS, means SUSPEND */
1457                 break;
1458         default:
1459                 dwc3_trace(trace_dwc3_gadget,
1460                                 "can't wakeup from '%s'\n",
1461                                 dwc3_gadget_link_string(link_state));
1462                 ret = -EINVAL;
1463                 goto out;
1464         }
1465
1466         ret = dwc3_gadget_set_link_state(dwc, DWC3_LINK_STATE_RECOV);
1467         if (ret < 0) {
1468                 dev_err(dwc->dev, "failed to put link in Recovery\n");
1469                 goto out;
1470         }
1471
1472         /* Recent versions do this automatically */
1473         if (dwc->revision < DWC3_REVISION_194A) {
1474                 /* write zeroes to Link Change Request */
1475                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1476                 reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
1477                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1478         }
1479
1480         /* poll until Link State changes to ON */
1481         timeout = jiffies + msecs_to_jiffies(100);
1482
1483         while (!time_after(jiffies, timeout)) {
1484                 reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1485
1486                 /* in HS, means ON */
1487                 if (DWC3_DSTS_USBLNKST(reg) == DWC3_LINK_STATE_U0)
1488                         break;
1489         }
1490
1491         if (DWC3_DSTS_USBLNKST(reg) != DWC3_LINK_STATE_U0) {
1492                 dev_err(dwc->dev, "failed to send remote wakeup\n");
1493                 ret = -EINVAL;
1494         }
1495
1496 out:
1497         spin_unlock_irqrestore(&dwc->lock, flags);
1498
1499         return ret;
1500 }
1501
1502 static int dwc3_gadget_set_selfpowered(struct usb_gadget *g,
1503                 int is_selfpowered)
1504 {
1505         struct dwc3             *dwc = gadget_to_dwc(g);
1506         unsigned long           flags;
1507
1508         spin_lock_irqsave(&dwc->lock, flags);
1509         g->is_selfpowered = !!is_selfpowered;
1510         spin_unlock_irqrestore(&dwc->lock, flags);
1511
1512         return 0;
1513 }
1514
1515 static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
1516 {
1517         u32                     reg;
1518         u32                     timeout = 500;
1519
1520         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1521         if (is_on) {
1522                 if (dwc->revision <= DWC3_REVISION_187A) {
1523                         reg &= ~DWC3_DCTL_TRGTULST_MASK;
1524                         reg |= DWC3_DCTL_TRGTULST_RX_DET;
1525                 }
1526
1527                 if (dwc->revision >= DWC3_REVISION_194A)
1528                         reg &= ~DWC3_DCTL_KEEP_CONNECT;
1529                 reg |= DWC3_DCTL_RUN_STOP;
1530
1531                 if (dwc->has_hibernation)
1532                         reg |= DWC3_DCTL_KEEP_CONNECT;
1533
1534                 dwc->pullups_connected = true;
1535         } else {
1536                 reg &= ~DWC3_DCTL_RUN_STOP;
1537
1538                 if (dwc->has_hibernation && !suspend)
1539                         reg &= ~DWC3_DCTL_KEEP_CONNECT;
1540
1541                 dwc->pullups_connected = false;
1542         }
1543
1544         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1545
1546         do {
1547                 reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1548                 if (is_on) {
1549                         if (!(reg & DWC3_DSTS_DEVCTRLHLT))
1550                                 break;
1551                 } else {
1552                         if (reg & DWC3_DSTS_DEVCTRLHLT)
1553                                 break;
1554                 }
1555                 timeout--;
1556                 if (!timeout)
1557                         return -ETIMEDOUT;
1558                 udelay(1);
1559         } while (1);
1560
1561         dwc3_trace(trace_dwc3_gadget, "gadget %s data soft-%s",
1562                         dwc->gadget_driver
1563                         ? dwc->gadget_driver->function : "no-function",
1564                         is_on ? "connect" : "disconnect");
1565
1566         return 0;
1567 }
1568
1569 static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
1570 {
1571         struct dwc3             *dwc = gadget_to_dwc(g);
1572         unsigned long           flags;
1573         int                     ret;
1574
1575         is_on = !!is_on;
1576
1577         spin_lock_irqsave(&dwc->lock, flags);
1578         ret = dwc3_gadget_run_stop(dwc, is_on, false);
1579         spin_unlock_irqrestore(&dwc->lock, flags);
1580
1581         return ret;
1582 }
1583
1584 static void dwc3_gadget_enable_irq(struct dwc3 *dwc)
1585 {
1586         u32                     reg;
1587
1588         /* Enable all but Start and End of Frame IRQs */
1589         reg = (DWC3_DEVTEN_VNDRDEVTSTRCVEDEN |
1590                         DWC3_DEVTEN_EVNTOVERFLOWEN |
1591                         DWC3_DEVTEN_CMDCMPLTEN |
1592                         DWC3_DEVTEN_ERRTICERREN |
1593                         DWC3_DEVTEN_WKUPEVTEN |
1594                         DWC3_DEVTEN_ULSTCNGEN |
1595                         DWC3_DEVTEN_CONNECTDONEEN |
1596                         DWC3_DEVTEN_USBRSTEN |
1597                         DWC3_DEVTEN_DISCONNEVTEN);
1598
1599         dwc3_writel(dwc->regs, DWC3_DEVTEN, reg);
1600 }
1601
1602 static void dwc3_gadget_disable_irq(struct dwc3 *dwc)
1603 {
1604         /* mask all interrupts */
1605         dwc3_writel(dwc->regs, DWC3_DEVTEN, 0x00);
1606 }
1607
1608 static irqreturn_t dwc3_interrupt(int irq, void *_dwc);
1609 static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc);
1610
1611 static int dwc3_gadget_start(struct usb_gadget *g,
1612                 struct usb_gadget_driver *driver)
1613 {
1614         struct dwc3             *dwc = gadget_to_dwc(g);
1615         struct dwc3_ep          *dep;
1616         unsigned long           flags;
1617         int                     ret = 0;
1618         int                     irq;
1619         u32                     reg;
1620
1621         irq = platform_get_irq(to_platform_device(dwc->dev), 0);
1622         ret = request_threaded_irq(irq, dwc3_interrupt, dwc3_thread_interrupt,
1623                         IRQF_SHARED, "dwc3", dwc);
1624         if (ret) {
1625                 dev_err(dwc->dev, "failed to request irq #%d --> %d\n",
1626                                 irq, ret);
1627                 goto err0;
1628         }
1629
1630         spin_lock_irqsave(&dwc->lock, flags);
1631
1632         if (dwc->gadget_driver) {
1633                 dev_err(dwc->dev, "%s is already bound to %s\n",
1634                                 dwc->gadget.name,
1635                                 dwc->gadget_driver->driver.name);
1636                 ret = -EBUSY;
1637                 goto err1;
1638         }
1639
1640         dwc->gadget_driver      = driver;
1641
1642         reg = dwc3_readl(dwc->regs, DWC3_DCFG);
1643         reg &= ~(DWC3_DCFG_SPEED_MASK);
1644
1645         /**
1646          * WORKAROUND: DWC3 revision < 2.20a have an issue
1647          * which would cause metastability state on Run/Stop
1648          * bit if we try to force the IP to USB2-only mode.
1649          *
1650          * Because of that, we cannot configure the IP to any
1651          * speed other than the SuperSpeed
1652          *
1653          * Refers to:
1654          *
1655          * STAR#9000525659: Clock Domain Crossing on DCTL in
1656          * USB 2.0 Mode
1657          */
1658         if (dwc->revision < DWC3_REVISION_220A) {
1659                 reg |= DWC3_DCFG_SUPERSPEED;
1660         } else {
1661                 switch (dwc->maximum_speed) {
1662                 case USB_SPEED_LOW:
1663                         reg |= DWC3_DSTS_LOWSPEED;
1664                         break;
1665                 case USB_SPEED_FULL:
1666                         reg |= DWC3_DSTS_FULLSPEED1;
1667                         break;
1668                 case USB_SPEED_HIGH:
1669                         reg |= DWC3_DSTS_HIGHSPEED;
1670                         break;
1671                 case USB_SPEED_SUPER_PLUS:
1672                         reg |= DWC3_DSTS_SUPERSPEED_PLUS;
1673                         break;
1674                 default:
1675                         dev_err(dwc->dev, "invalid dwc->maximum_speed (%d)\n",
1676                                 dwc->maximum_speed);
1677                         /* fall through */
1678                 case USB_SPEED_SUPER:
1679                         reg |= DWC3_DCFG_SUPERSPEED;
1680                         break;
1681                 }
1682         }
1683         dwc3_writel(dwc->regs, DWC3_DCFG, reg);
1684
1685         /* Start with SuperSpeed Default */
1686         dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
1687
1688         dep = dwc->eps[0];
1689         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
1690                         false);
1691         if (ret) {
1692                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
1693                 goto err2;
1694         }
1695
1696         dep = dwc->eps[1];
1697         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
1698                         false);
1699         if (ret) {
1700                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
1701                 goto err3;
1702         }
1703
1704         /* begin to receive SETUP packets */
1705         dwc->ep0state = EP0_SETUP_PHASE;
1706         dwc3_ep0_out_start(dwc);
1707
1708         dwc3_gadget_enable_irq(dwc);
1709
1710         spin_unlock_irqrestore(&dwc->lock, flags);
1711
1712         return 0;
1713
1714 err3:
1715         __dwc3_gadget_ep_disable(dwc->eps[0]);
1716
1717 err2:
1718         dwc->gadget_driver = NULL;
1719
1720 err1:
1721         spin_unlock_irqrestore(&dwc->lock, flags);
1722
1723         free_irq(irq, dwc);
1724
1725 err0:
1726         return ret;
1727 }
1728
1729 static int dwc3_gadget_stop(struct usb_gadget *g)
1730 {
1731         struct dwc3             *dwc = gadget_to_dwc(g);
1732         unsigned long           flags;
1733         int                     irq;
1734
1735         spin_lock_irqsave(&dwc->lock, flags);
1736
1737         dwc3_gadget_disable_irq(dwc);
1738         __dwc3_gadget_ep_disable(dwc->eps[0]);
1739         __dwc3_gadget_ep_disable(dwc->eps[1]);
1740
1741         dwc->gadget_driver      = NULL;
1742
1743         spin_unlock_irqrestore(&dwc->lock, flags);
1744
1745         irq = platform_get_irq(to_platform_device(dwc->dev), 0);
1746         free_irq(irq, dwc);
1747
1748         return 0;
1749 }
1750
1751 static const struct usb_gadget_ops dwc3_gadget_ops = {
1752         .get_frame              = dwc3_gadget_get_frame,
1753         .wakeup                 = dwc3_gadget_wakeup,
1754         .set_selfpowered        = dwc3_gadget_set_selfpowered,
1755         .pullup                 = dwc3_gadget_pullup,
1756         .udc_start              = dwc3_gadget_start,
1757         .udc_stop               = dwc3_gadget_stop,
1758 };
1759
1760 /* -------------------------------------------------------------------------- */
1761
1762 static int dwc3_gadget_init_hw_endpoints(struct dwc3 *dwc,
1763                 u8 num, u32 direction)
1764 {
1765         struct dwc3_ep                  *dep;
1766         u8                              i;
1767
1768         for (i = 0; i < num; i++) {
1769                 u8 epnum = (i << 1) | (!!direction);
1770
1771                 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
1772                 if (!dep)
1773                         return -ENOMEM;
1774
1775                 dep->dwc = dwc;
1776                 dep->number = epnum;
1777                 dep->direction = !!direction;
1778                 dwc->eps[epnum] = dep;
1779
1780                 snprintf(dep->name, sizeof(dep->name), "ep%d%s", epnum >> 1,
1781                                 (epnum & 1) ? "in" : "out");
1782
1783                 dep->endpoint.name = dep->name;
1784
1785                 dwc3_trace(trace_dwc3_gadget, "initializing %s", dep->name);
1786
1787                 if (epnum == 0 || epnum == 1) {
1788                         usb_ep_set_maxpacket_limit(&dep->endpoint, 512);
1789                         dep->endpoint.maxburst = 1;
1790                         dep->endpoint.ops = &dwc3_gadget_ep0_ops;
1791                         if (!epnum)
1792                                 dwc->gadget.ep0 = &dep->endpoint;
1793                 } else {
1794                         int             ret;
1795
1796                         usb_ep_set_maxpacket_limit(&dep->endpoint, 1024);
1797                         dep->endpoint.max_streams = 15;
1798                         dep->endpoint.ops = &dwc3_gadget_ep_ops;
1799                         list_add_tail(&dep->endpoint.ep_list,
1800                                         &dwc->gadget.ep_list);
1801
1802                         ret = dwc3_alloc_trb_pool(dep);
1803                         if (ret)
1804                                 return ret;
1805                 }
1806
1807                 if (epnum == 0 || epnum == 1) {
1808                         dep->endpoint.caps.type_control = true;
1809                 } else {
1810                         dep->endpoint.caps.type_iso = true;
1811                         dep->endpoint.caps.type_bulk = true;
1812                         dep->endpoint.caps.type_int = true;
1813                 }
1814
1815                 dep->endpoint.caps.dir_in = !!direction;
1816                 dep->endpoint.caps.dir_out = !direction;
1817
1818                 INIT_LIST_HEAD(&dep->request_list);
1819                 INIT_LIST_HEAD(&dep->req_queued);
1820         }
1821
1822         return 0;
1823 }
1824
1825 static int dwc3_gadget_init_endpoints(struct dwc3 *dwc)
1826 {
1827         int                             ret;
1828
1829         INIT_LIST_HEAD(&dwc->gadget.ep_list);
1830
1831         ret = dwc3_gadget_init_hw_endpoints(dwc, dwc->num_out_eps, 0);
1832         if (ret < 0) {
1833                 dwc3_trace(trace_dwc3_gadget,
1834                                 "failed to allocate OUT endpoints");
1835                 return ret;
1836         }
1837
1838         ret = dwc3_gadget_init_hw_endpoints(dwc, dwc->num_in_eps, 1);
1839         if (ret < 0) {
1840                 dwc3_trace(trace_dwc3_gadget,
1841                                 "failed to allocate IN endpoints");
1842                 return ret;
1843         }
1844
1845         return 0;
1846 }
1847
1848 static void dwc3_gadget_free_endpoints(struct dwc3 *dwc)
1849 {
1850         struct dwc3_ep                  *dep;
1851         u8                              epnum;
1852
1853         for (epnum = 0; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
1854                 dep = dwc->eps[epnum];
1855                 if (!dep)
1856                         continue;
1857                 /*
1858                  * Physical endpoints 0 and 1 are special; they form the
1859                  * bi-directional USB endpoint 0.
1860                  *
1861                  * For those two physical endpoints, we don't allocate a TRB
1862                  * pool nor do we add them the endpoints list. Due to that, we
1863                  * shouldn't do these two operations otherwise we would end up
1864                  * with all sorts of bugs when removing dwc3.ko.
1865                  */
1866                 if (epnum != 0 && epnum != 1) {
1867                         dwc3_free_trb_pool(dep);
1868                         list_del(&dep->endpoint.ep_list);
1869                 }
1870
1871                 kfree(dep);
1872         }
1873 }
1874
1875 /* -------------------------------------------------------------------------- */
1876
1877 static int __dwc3_cleanup_done_trbs(struct dwc3 *dwc, struct dwc3_ep *dep,
1878                 struct dwc3_request *req, struct dwc3_trb *trb,
1879                 const struct dwc3_event_depevt *event, int status)
1880 {
1881         unsigned int            count;
1882         unsigned int            s_pkt = 0;
1883         unsigned int            trb_status;
1884
1885         trace_dwc3_complete_trb(dep, trb);
1886
1887         if ((trb->ctrl & DWC3_TRB_CTRL_HWO) && status != -ESHUTDOWN)
1888                 /*
1889                  * We continue despite the error. There is not much we
1890                  * can do. If we don't clean it up we loop forever. If
1891                  * we skip the TRB then it gets overwritten after a
1892                  * while since we use them in a ring buffer. A BUG()
1893                  * would help. Lets hope that if this occurs, someone
1894                  * fixes the root cause instead of looking away :)
1895                  */
1896                 dev_err(dwc->dev, "%s's TRB (%p) still owned by HW\n",
1897                                 dep->name, trb);
1898         count = trb->size & DWC3_TRB_SIZE_MASK;
1899
1900         if (dep->direction) {
1901                 if (count) {
1902                         trb_status = DWC3_TRB_SIZE_TRBSTS(trb->size);
1903                         if (trb_status == DWC3_TRBSTS_MISSED_ISOC) {
1904                                 dwc3_trace(trace_dwc3_gadget,
1905                                                 "%s: incomplete IN transfer\n",
1906                                                 dep->name);
1907                                 /*
1908                                  * If missed isoc occurred and there is
1909                                  * no request queued then issue END
1910                                  * TRANSFER, so that core generates
1911                                  * next xfernotready and we will issue
1912                                  * a fresh START TRANSFER.
1913                                  * If there are still queued request
1914                                  * then wait, do not issue either END
1915                                  * or UPDATE TRANSFER, just attach next
1916                                  * request in request_list during
1917                                  * giveback.If any future queued request
1918                                  * is successfully transferred then we
1919                                  * will issue UPDATE TRANSFER for all
1920                                  * request in the request_list.
1921                                  */
1922                                 dep->flags |= DWC3_EP_MISSED_ISOC;
1923                         } else {
1924                                 dev_err(dwc->dev, "incomplete IN transfer %s\n",
1925                                                 dep->name);
1926                                 status = -ECONNRESET;
1927                         }
1928                 } else {
1929                         dep->flags &= ~DWC3_EP_MISSED_ISOC;
1930                 }
1931         } else {
1932                 if (count && (event->status & DEPEVT_STATUS_SHORT))
1933                         s_pkt = 1;
1934         }
1935
1936         /*
1937          * We assume here we will always receive the entire data block
1938          * which we should receive. Meaning, if we program RX to
1939          * receive 4K but we receive only 2K, we assume that's all we
1940          * should receive and we simply bounce the request back to the
1941          * gadget driver for further processing.
1942          */
1943         req->request.actual += req->request.length - count;
1944         if (s_pkt)
1945                 return 1;
1946         if ((event->status & DEPEVT_STATUS_LST) &&
1947                         (trb->ctrl & (DWC3_TRB_CTRL_LST |
1948                                 DWC3_TRB_CTRL_HWO)))
1949                 return 1;
1950         if ((event->status & DEPEVT_STATUS_IOC) &&
1951                         (trb->ctrl & DWC3_TRB_CTRL_IOC))
1952                 return 1;
1953         return 0;
1954 }
1955
1956 static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
1957                 const struct dwc3_event_depevt *event, int status)
1958 {
1959         struct dwc3_request     *req;
1960         struct dwc3_trb         *trb;
1961         unsigned int            slot;
1962         unsigned int            i;
1963         int                     ret;
1964
1965         do {
1966                 req = next_request(&dep->req_queued);
1967                 if (WARN_ON_ONCE(!req))
1968                         return 1;
1969
1970                 i = 0;
1971                 do {
1972                         slot = req->start_slot + i;
1973                         if ((slot == DWC3_TRB_NUM - 1) &&
1974                                 usb_endpoint_xfer_isoc(dep->endpoint.desc))
1975                                 slot++;
1976                         slot %= DWC3_TRB_NUM;
1977                         trb = &dep->trb_pool[slot];
1978
1979                         ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
1980                                         event, status);
1981                         if (ret)
1982                                 break;
1983                 } while (++i < req->request.num_mapped_sgs);
1984
1985                 dwc3_gadget_giveback(dep, req, status);
1986
1987                 if (ret)
1988                         break;
1989         } while (1);
1990
1991         if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
1992                         list_empty(&dep->req_queued)) {
1993                 if (list_empty(&dep->request_list)) {
1994                         /*
1995                          * If there is no entry in request list then do
1996                          * not issue END TRANSFER now. Just set PENDING
1997                          * flag, so that END TRANSFER is issued when an
1998                          * entry is added into request list.
1999                          */
2000                         dep->flags = DWC3_EP_PENDING_REQUEST;
2001                 } else {
2002                         dwc3_stop_active_transfer(dwc, dep->number, true);
2003                         dep->flags = DWC3_EP_ENABLED;
2004                 }
2005                 return 1;
2006         }
2007
2008         return 1;
2009 }
2010
2011 static void dwc3_endpoint_transfer_complete(struct dwc3 *dwc,
2012                 struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
2013 {
2014         unsigned                status = 0;
2015         int                     clean_busy;
2016         u32                     is_xfer_complete;
2017
2018         is_xfer_complete = (event->endpoint_event == DWC3_DEPEVT_XFERCOMPLETE);
2019
2020         if (event->status & DEPEVT_STATUS_BUSERR)
2021                 status = -ECONNRESET;
2022
2023         clean_busy = dwc3_cleanup_done_reqs(dwc, dep, event, status);
2024         if (clean_busy && (is_xfer_complete ||
2025                                 usb_endpoint_xfer_isoc(dep->endpoint.desc)))
2026                 dep->flags &= ~DWC3_EP_BUSY;
2027
2028         /*
2029          * WORKAROUND: This is the 2nd half of U1/U2 -> U0 workaround.
2030          * See dwc3_gadget_linksts_change_interrupt() for 1st half.
2031          */
2032         if (dwc->revision < DWC3_REVISION_183A) {
2033                 u32             reg;
2034                 int             i;
2035
2036                 for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
2037                         dep = dwc->eps[i];
2038
2039                         if (!(dep->flags & DWC3_EP_ENABLED))
2040                                 continue;
2041
2042                         if (!list_empty(&dep->req_queued))
2043                                 return;
2044                 }
2045
2046                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2047                 reg |= dwc->u1u2;
2048                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2049
2050                 dwc->u1u2 = 0;
2051         }
2052
2053         if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
2054                 int ret;
2055
2056                 ret = __dwc3_gadget_kick_transfer(dep, 0, is_xfer_complete);
2057                 if (!ret || ret == -EBUSY)
2058                         return;
2059         }
2060 }
2061
2062 static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
2063                 const struct dwc3_event_depevt *event)
2064 {
2065         struct dwc3_ep          *dep;
2066         u8                      epnum = event->endpoint_number;
2067
2068         dep = dwc->eps[epnum];
2069
2070         if (!(dep->flags & DWC3_EP_ENABLED))
2071                 return;
2072
2073         if (epnum == 0 || epnum == 1) {
2074                 dwc3_ep0_interrupt(dwc, event);
2075                 return;
2076         }
2077
2078         switch (event->endpoint_event) {
2079         case DWC3_DEPEVT_XFERCOMPLETE:
2080                 dep->resource_index = 0;
2081
2082                 if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
2083                         dwc3_trace(trace_dwc3_gadget,
2084                                         "%s is an Isochronous endpoint\n",
2085                                         dep->name);
2086                         return;
2087                 }
2088
2089                 dwc3_endpoint_transfer_complete(dwc, dep, event);
2090                 break;
2091         case DWC3_DEPEVT_XFERINPROGRESS:
2092                 dwc3_endpoint_transfer_complete(dwc, dep, event);
2093                 break;
2094         case DWC3_DEPEVT_XFERNOTREADY:
2095                 if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
2096                         dwc3_gadget_start_isoc(dwc, dep, event);
2097                 } else {
2098                         int active;
2099                         int ret;
2100
2101                         active = event->status & DEPEVT_STATUS_TRANSFER_ACTIVE;
2102
2103                         dwc3_trace(trace_dwc3_gadget, "%s: reason %s",
2104                                         dep->name, active ? "Transfer Active"
2105                                         : "Transfer Not Active");
2106
2107                         ret = __dwc3_gadget_kick_transfer(dep, 0, !active);
2108                         if (!ret || ret == -EBUSY)
2109                                 return;
2110
2111                         dwc3_trace(trace_dwc3_gadget,
2112                                         "%s: failed to kick transfers\n",
2113                                         dep->name);
2114                 }
2115
2116                 break;
2117         case DWC3_DEPEVT_STREAMEVT:
2118                 if (!usb_endpoint_xfer_bulk(dep->endpoint.desc)) {
2119                         dev_err(dwc->dev, "Stream event for non-Bulk %s\n",
2120                                         dep->name);
2121                         return;
2122                 }
2123
2124                 switch (event->status) {
2125                 case DEPEVT_STREAMEVT_FOUND:
2126                         dwc3_trace(trace_dwc3_gadget,
2127                                         "Stream %d found and started",
2128                                         event->parameters);
2129
2130                         break;
2131                 case DEPEVT_STREAMEVT_NOTFOUND:
2132                         /* FALLTHROUGH */
2133                 default:
2134                         dwc3_trace(trace_dwc3_gadget,
2135                                         "unable to find suitable stream\n");
2136                 }
2137                 break;
2138         case DWC3_DEPEVT_RXTXFIFOEVT:
2139                 dwc3_trace(trace_dwc3_gadget, "%s FIFO Overrun\n", dep->name);
2140                 break;
2141         case DWC3_DEPEVT_EPCMDCMPLT:
2142                 dwc3_trace(trace_dwc3_gadget, "Endpoint Command Complete");
2143                 break;
2144         }
2145 }
2146
2147 static void dwc3_disconnect_gadget(struct dwc3 *dwc)
2148 {
2149         if (dwc->gadget_driver && dwc->gadget_driver->disconnect) {
2150                 spin_unlock(&dwc->lock);
2151                 dwc->gadget_driver->disconnect(&dwc->gadget);
2152                 spin_lock(&dwc->lock);
2153         }
2154 }
2155
2156 static void dwc3_suspend_gadget(struct dwc3 *dwc)
2157 {
2158         if (dwc->gadget_driver && dwc->gadget_driver->suspend) {
2159                 spin_unlock(&dwc->lock);
2160                 dwc->gadget_driver->suspend(&dwc->gadget);
2161                 spin_lock(&dwc->lock);
2162         }
2163 }
2164
2165 static void dwc3_resume_gadget(struct dwc3 *dwc)
2166 {
2167         if (dwc->gadget_driver && dwc->gadget_driver->resume) {
2168                 spin_unlock(&dwc->lock);
2169                 dwc->gadget_driver->resume(&dwc->gadget);
2170                 spin_lock(&dwc->lock);
2171         }
2172 }
2173
2174 static void dwc3_reset_gadget(struct dwc3 *dwc)
2175 {
2176         if (!dwc->gadget_driver)
2177                 return;
2178
2179         if (dwc->gadget.speed != USB_SPEED_UNKNOWN) {
2180                 spin_unlock(&dwc->lock);
2181                 usb_gadget_udc_reset(&dwc->gadget, dwc->gadget_driver);
2182                 spin_lock(&dwc->lock);
2183         }
2184 }
2185
2186 static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force)
2187 {
2188         struct dwc3_ep *dep;
2189         struct dwc3_gadget_ep_cmd_params params;
2190         u32 cmd;
2191         int ret;
2192
2193         dep = dwc->eps[epnum];
2194
2195         if (!dep->resource_index)
2196                 return;
2197
2198         /*
2199          * NOTICE: We are violating what the Databook says about the
2200          * EndTransfer command. Ideally we would _always_ wait for the
2201          * EndTransfer Command Completion IRQ, but that's causing too
2202          * much trouble synchronizing between us and gadget driver.
2203          *
2204          * We have discussed this with the IP Provider and it was
2205          * suggested to giveback all requests here, but give HW some
2206          * extra time to synchronize with the interconnect. We're using
2207          * an arbitrary 100us delay for that.
2208          *
2209          * Note also that a similar handling was tested by Synopsys
2210          * (thanks a lot Paul) and nothing bad has come out of it.
2211          * In short, what we're doing is:
2212          *
2213          * - Issue EndTransfer WITH CMDIOC bit set
2214          * - Wait 100us
2215          */
2216
2217         cmd = DWC3_DEPCMD_ENDTRANSFER;
2218         cmd |= force ? DWC3_DEPCMD_HIPRI_FORCERM : 0;
2219         cmd |= DWC3_DEPCMD_CMDIOC;
2220         cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
2221         memset(&params, 0, sizeof(params));
2222         ret = dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, &params);
2223         WARN_ON_ONCE(ret);
2224         dep->resource_index = 0;
2225         dep->flags &= ~DWC3_EP_BUSY;
2226         udelay(100);
2227 }
2228
2229 static void dwc3_stop_active_transfers(struct dwc3 *dwc)
2230 {
2231         u32 epnum;
2232
2233         for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
2234                 struct dwc3_ep *dep;
2235
2236                 dep = dwc->eps[epnum];
2237                 if (!dep)
2238                         continue;
2239
2240                 if (!(dep->flags & DWC3_EP_ENABLED))
2241                         continue;
2242
2243                 dwc3_remove_requests(dwc, dep);
2244         }
2245 }
2246
2247 static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)
2248 {
2249         u32 epnum;
2250
2251         for (epnum = 1; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
2252                 struct dwc3_ep *dep;
2253                 struct dwc3_gadget_ep_cmd_params params;
2254                 int ret;
2255
2256                 dep = dwc->eps[epnum];
2257                 if (!dep)
2258                         continue;
2259
2260                 if (!(dep->flags & DWC3_EP_STALL))
2261                         continue;
2262
2263                 dep->flags &= ~DWC3_EP_STALL;
2264
2265                 memset(&params, 0, sizeof(params));
2266                 ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
2267                                 DWC3_DEPCMD_CLEARSTALL, &params);
2268                 WARN_ON_ONCE(ret);
2269         }
2270 }
2271
2272 static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
2273 {
2274         int                     reg;
2275
2276         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2277         reg &= ~DWC3_DCTL_INITU1ENA;
2278         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2279
2280         reg &= ~DWC3_DCTL_INITU2ENA;
2281         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2282
2283         dwc3_disconnect_gadget(dwc);
2284
2285         dwc->gadget.speed = USB_SPEED_UNKNOWN;
2286         dwc->setup_packet_pending = false;
2287         usb_gadget_set_state(&dwc->gadget, USB_STATE_NOTATTACHED);
2288 }
2289
2290 static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
2291 {
2292         u32                     reg;
2293
2294         /*
2295          * WORKAROUND: DWC3 revisions <1.88a have an issue which
2296          * would cause a missing Disconnect Event if there's a
2297          * pending Setup Packet in the FIFO.
2298          *
2299          * There's no suggested workaround on the official Bug
2300          * report, which states that "unless the driver/application
2301          * is doing any special handling of a disconnect event,
2302          * there is no functional issue".
2303          *
2304          * Unfortunately, it turns out that we _do_ some special
2305          * handling of a disconnect event, namely complete all
2306          * pending transfers, notify gadget driver of the
2307          * disconnection, and so on.
2308          *
2309          * Our suggested workaround is to follow the Disconnect
2310          * Event steps here, instead, based on a setup_packet_pending
2311          * flag. Such flag gets set whenever we have a SETUP_PENDING
2312          * status for EP0 TRBs and gets cleared on XferComplete for the
2313          * same endpoint.
2314          *
2315          * Refers to:
2316          *
2317          * STAR#9000466709: RTL: Device : Disconnect event not
2318          * generated if setup packet pending in FIFO
2319          */
2320         if (dwc->revision < DWC3_REVISION_188A) {
2321                 if (dwc->setup_packet_pending)
2322                         dwc3_gadget_disconnect_interrupt(dwc);
2323         }
2324
2325         dwc3_reset_gadget(dwc);
2326
2327         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2328         reg &= ~DWC3_DCTL_TSTCTRL_MASK;
2329         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2330         dwc->test_mode = false;
2331
2332         dwc3_stop_active_transfers(dwc);
2333         dwc3_clear_stall_all_ep(dwc);
2334
2335         /* Reset device address to zero */
2336         reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2337         reg &= ~(DWC3_DCFG_DEVADDR_MASK);
2338         dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2339 }
2340
2341 static void dwc3_update_ram_clk_sel(struct dwc3 *dwc, u32 speed)
2342 {
2343         u32 reg;
2344         u32 usb30_clock = DWC3_GCTL_CLK_BUS;
2345
2346         /*
2347          * We change the clock only at SS but I dunno why I would want to do
2348          * this. Maybe it becomes part of the power saving plan.
2349          */
2350
2351         if ((speed != DWC3_DSTS_SUPERSPEED) &&
2352             (speed != DWC3_DSTS_SUPERSPEED_PLUS))
2353                 return;
2354
2355         /*
2356          * RAMClkSel is reset to 0 after USB reset, so it must be reprogrammed
2357          * each time on Connect Done.
2358          */
2359         if (!usb30_clock)
2360                 return;
2361
2362         reg = dwc3_readl(dwc->regs, DWC3_GCTL);
2363         reg |= DWC3_GCTL_RAMCLKSEL(usb30_clock);
2364         dwc3_writel(dwc->regs, DWC3_GCTL, reg);
2365 }
2366
2367 static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
2368 {
2369         struct dwc3_ep          *dep;
2370         int                     ret;
2371         u32                     reg;
2372         u8                      speed;
2373
2374         reg = dwc3_readl(dwc->regs, DWC3_DSTS);
2375         speed = reg & DWC3_DSTS_CONNECTSPD;
2376         dwc->speed = speed;
2377
2378         dwc3_update_ram_clk_sel(dwc, speed);
2379
2380         switch (speed) {
2381         case DWC3_DCFG_SUPERSPEED_PLUS:
2382                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
2383                 dwc->gadget.ep0->maxpacket = 512;
2384                 dwc->gadget.speed = USB_SPEED_SUPER_PLUS;
2385                 break;
2386         case DWC3_DCFG_SUPERSPEED:
2387                 /*
2388                  * WORKAROUND: DWC3 revisions <1.90a have an issue which
2389                  * would cause a missing USB3 Reset event.
2390                  *
2391                  * In such situations, we should force a USB3 Reset
2392                  * event by calling our dwc3_gadget_reset_interrupt()
2393                  * routine.
2394                  *
2395                  * Refers to:
2396                  *
2397                  * STAR#9000483510: RTL: SS : USB3 reset event may
2398                  * not be generated always when the link enters poll
2399                  */
2400                 if (dwc->revision < DWC3_REVISION_190A)
2401                         dwc3_gadget_reset_interrupt(dwc);
2402
2403                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
2404                 dwc->gadget.ep0->maxpacket = 512;
2405                 dwc->gadget.speed = USB_SPEED_SUPER;
2406                 break;
2407         case DWC3_DCFG_HIGHSPEED:
2408                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
2409                 dwc->gadget.ep0->maxpacket = 64;
2410                 dwc->gadget.speed = USB_SPEED_HIGH;
2411                 break;
2412         case DWC3_DCFG_FULLSPEED2:
2413         case DWC3_DCFG_FULLSPEED1:
2414                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
2415                 dwc->gadget.ep0->maxpacket = 64;
2416                 dwc->gadget.speed = USB_SPEED_FULL;
2417                 break;
2418         case DWC3_DCFG_LOWSPEED:
2419                 dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(8);
2420                 dwc->gadget.ep0->maxpacket = 8;
2421                 dwc->gadget.speed = USB_SPEED_LOW;
2422                 break;
2423         }
2424
2425         /* Enable USB2 LPM Capability */
2426
2427         if ((dwc->revision > DWC3_REVISION_194A) &&
2428             (speed != DWC3_DCFG_SUPERSPEED) &&
2429             (speed != DWC3_DCFG_SUPERSPEED_PLUS)) {
2430                 reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2431                 reg |= DWC3_DCFG_LPM_CAP;
2432                 dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2433
2434                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2435                 reg &= ~(DWC3_DCTL_HIRD_THRES_MASK | DWC3_DCTL_L1_HIBER_EN);
2436
2437                 reg |= DWC3_DCTL_HIRD_THRES(dwc->hird_threshold);
2438
2439                 /*
2440                  * When dwc3 revisions >= 2.40a, LPM Erratum is enabled and
2441                  * DCFG.LPMCap is set, core responses with an ACK and the
2442                  * BESL value in the LPM token is less than or equal to LPM
2443                  * NYET threshold.
2444                  */
2445                 WARN_ONCE(dwc->revision < DWC3_REVISION_240A
2446                                 && dwc->has_lpm_erratum,
2447                                 "LPM Erratum not available on dwc3 revisisions < 2.40a\n");
2448
2449                 if (dwc->has_lpm_erratum && dwc->revision >= DWC3_REVISION_240A)
2450                         reg |= DWC3_DCTL_LPM_ERRATA(dwc->lpm_nyet_threshold);
2451
2452                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2453         } else {
2454                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2455                 reg &= ~DWC3_DCTL_HIRD_THRES_MASK;
2456                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2457         }
2458
2459         dep = dwc->eps[0];
2460         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true,
2461                         false);
2462         if (ret) {
2463                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
2464                 return;
2465         }
2466
2467         dep = dwc->eps[1];
2468         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true,
2469                         false);
2470         if (ret) {
2471                 dev_err(dwc->dev, "failed to enable %s\n", dep->name);
2472                 return;
2473         }
2474
2475         /*
2476          * Configure PHY via GUSB3PIPECTLn if required.
2477          *
2478          * Update GTXFIFOSIZn
2479          *
2480          * In both cases reset values should be sufficient.
2481          */
2482 }
2483
2484 static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc)
2485 {
2486         /*
2487          * TODO take core out of low power mode when that's
2488          * implemented.
2489          */
2490
2491         if (dwc->gadget_driver && dwc->gadget_driver->resume) {
2492                 spin_unlock(&dwc->lock);
2493                 dwc->gadget_driver->resume(&dwc->gadget);
2494                 spin_lock(&dwc->lock);
2495         }
2496 }
2497
2498 static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
2499                 unsigned int evtinfo)
2500 {
2501         enum dwc3_link_state    next = evtinfo & DWC3_LINK_STATE_MASK;
2502         unsigned int            pwropt;
2503
2504         /*
2505          * WORKAROUND: DWC3 < 2.50a have an issue when configured without
2506          * Hibernation mode enabled which would show up when device detects
2507          * host-initiated U3 exit.
2508          *
2509          * In that case, device will generate a Link State Change Interrupt
2510          * from U3 to RESUME which is only necessary if Hibernation is
2511          * configured in.
2512          *
2513          * There are no functional changes due to such spurious event and we
2514          * just need to ignore it.
2515          *
2516          * Refers to:
2517          *
2518          * STAR#9000570034 RTL: SS Resume event generated in non-Hibernation
2519          * operational mode
2520          */
2521         pwropt = DWC3_GHWPARAMS1_EN_PWROPT(dwc->hwparams.hwparams1);
2522         if ((dwc->revision < DWC3_REVISION_250A) &&
2523                         (pwropt != DWC3_GHWPARAMS1_EN_PWROPT_HIB)) {
2524                 if ((dwc->link_state == DWC3_LINK_STATE_U3) &&
2525                                 (next == DWC3_LINK_STATE_RESUME)) {
2526                         dwc3_trace(trace_dwc3_gadget,
2527                                         "ignoring transition U3 -> Resume");
2528                         return;
2529                 }
2530         }
2531
2532         /*
2533          * WORKAROUND: DWC3 Revisions <1.83a have an issue which, depending
2534          * on the link partner, the USB session might do multiple entry/exit
2535          * of low power states before a transfer takes place.
2536          *
2537          * Due to this problem, we might experience lower throughput. The
2538          * suggested workaround is to disable DCTL[12:9] bits if we're
2539          * transitioning from U1/U2 to U0 and enable those bits again
2540          * after a transfer completes and there are no pending transfers
2541          * on any of the enabled endpoints.
2542          *
2543          * This is the first half of that workaround.
2544          *
2545          * Refers to:
2546          *
2547          * STAR#9000446952: RTL: Device SS : if U1/U2 ->U0 takes >128us
2548          * core send LGO_Ux entering U0
2549          */
2550         if (dwc->revision < DWC3_REVISION_183A) {
2551                 if (next == DWC3_LINK_STATE_U0) {
2552                         u32     u1u2;
2553                         u32     reg;
2554
2555                         switch (dwc->link_state) {
2556                         case DWC3_LINK_STATE_U1:
2557                         case DWC3_LINK_STATE_U2:
2558                                 reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2559                                 u1u2 = reg & (DWC3_DCTL_INITU2ENA
2560                                                 | DWC3_DCTL_ACCEPTU2ENA
2561                                                 | DWC3_DCTL_INITU1ENA
2562                                                 | DWC3_DCTL_ACCEPTU1ENA);
2563
2564                                 if (!dwc->u1u2)
2565                                         dwc->u1u2 = reg & u1u2;
2566
2567                                 reg &= ~u1u2;
2568
2569                                 dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2570                                 break;
2571                         default:
2572                                 /* do nothing */
2573                                 break;
2574                         }
2575                 }
2576         }
2577
2578         switch (next) {
2579         case DWC3_LINK_STATE_U1:
2580                 if (dwc->speed == USB_SPEED_SUPER)
2581                         dwc3_suspend_gadget(dwc);
2582                 break;
2583         case DWC3_LINK_STATE_U2:
2584         case DWC3_LINK_STATE_U3:
2585                 dwc3_suspend_gadget(dwc);
2586                 break;
2587         case DWC3_LINK_STATE_RESUME:
2588                 dwc3_resume_gadget(dwc);
2589                 break;
2590         default:
2591                 /* do nothing */
2592                 break;
2593         }
2594
2595         dwc->link_state = next;
2596 }
2597
2598 static void dwc3_gadget_hibernation_interrupt(struct dwc3 *dwc,
2599                 unsigned int evtinfo)
2600 {
2601         unsigned int is_ss = evtinfo & BIT(4);
2602
2603         /**
2604          * WORKAROUND: DWC3 revison 2.20a with hibernation support
2605          * have a known issue which can cause USB CV TD.9.23 to fail
2606          * randomly.
2607          *
2608          * Because of this issue, core could generate bogus hibernation
2609          * events which SW needs to ignore.
2610          *
2611          * Refers to:
2612          *
2613          * STAR#9000546576: Device Mode Hibernation: Issue in USB 2.0
2614          * Device Fallback from SuperSpeed
2615          */
2616         if (is_ss ^ (dwc->speed == USB_SPEED_SUPER))
2617                 return;
2618
2619         /* enter hibernation here */
2620 }
2621
2622 static void dwc3_gadget_interrupt(struct dwc3 *dwc,
2623                 const struct dwc3_event_devt *event)
2624 {
2625         switch (event->type) {
2626         case DWC3_DEVICE_EVENT_DISCONNECT:
2627                 dwc3_gadget_disconnect_interrupt(dwc);
2628                 break;
2629         case DWC3_DEVICE_EVENT_RESET:
2630                 dwc3_gadget_reset_interrupt(dwc);
2631                 break;
2632         case DWC3_DEVICE_EVENT_CONNECT_DONE:
2633                 dwc3_gadget_conndone_interrupt(dwc);
2634                 break;
2635         case DWC3_DEVICE_EVENT_WAKEUP:
2636                 dwc3_gadget_wakeup_interrupt(dwc);
2637                 break;
2638         case DWC3_DEVICE_EVENT_HIBER_REQ:
2639                 if (dev_WARN_ONCE(dwc->dev, !dwc->has_hibernation,
2640                                         "unexpected hibernation event\n"))
2641                         break;
2642
2643                 dwc3_gadget_hibernation_interrupt(dwc, event->event_info);
2644                 break;
2645         case DWC3_DEVICE_EVENT_LINK_STATUS_CHANGE:
2646                 dwc3_gadget_linksts_change_interrupt(dwc, event->event_info);
2647                 break;
2648         case DWC3_DEVICE_EVENT_EOPF:
2649                 dwc3_trace(trace_dwc3_gadget, "End of Periodic Frame");
2650                 break;
2651         case DWC3_DEVICE_EVENT_SOF:
2652                 dwc3_trace(trace_dwc3_gadget, "Start of Periodic Frame");
2653                 break;
2654         case DWC3_DEVICE_EVENT_ERRATIC_ERROR:
2655                 dwc3_trace(trace_dwc3_gadget, "Erratic Error");
2656                 break;
2657         case DWC3_DEVICE_EVENT_CMD_CMPL:
2658                 dwc3_trace(trace_dwc3_gadget, "Command Complete");
2659                 break;
2660         case DWC3_DEVICE_EVENT_OVERFLOW:
2661                 dwc3_trace(trace_dwc3_gadget, "Overflow");
2662                 break;
2663         default:
2664                 dev_WARN(dwc->dev, "UNKNOWN IRQ %d\n", event->type);
2665         }
2666 }
2667
2668 static void dwc3_process_event_entry(struct dwc3 *dwc,
2669                 const union dwc3_event *event)
2670 {
2671         trace_dwc3_event(event->raw);
2672
2673         /* Endpoint IRQ, handle it and return early */
2674         if (event->type.is_devspec == 0) {
2675                 /* depevt */
2676                 return dwc3_endpoint_interrupt(dwc, &event->depevt);
2677         }
2678
2679         switch (event->type.type) {
2680         case DWC3_EVENT_TYPE_DEV:
2681                 dwc3_gadget_interrupt(dwc, &event->devt);
2682                 break;
2683         /* REVISIT what to do with Carkit and I2C events ? */
2684         default:
2685                 dev_err(dwc->dev, "UNKNOWN IRQ type %d\n", event->raw);
2686         }
2687 }
2688
2689 static irqreturn_t dwc3_process_event_buf(struct dwc3 *dwc, u32 buf)
2690 {
2691         struct dwc3_event_buffer *evt;
2692         irqreturn_t ret = IRQ_NONE;
2693         int left;
2694         u32 reg;
2695
2696         evt = dwc->ev_buffs[buf];
2697         left = evt->count;
2698
2699         if (!(evt->flags & DWC3_EVENT_PENDING))
2700                 return IRQ_NONE;
2701
2702         while (left > 0) {
2703                 union dwc3_event event;
2704
2705                 event.raw = *(u32 *) (evt->buf + evt->lpos);
2706
2707                 dwc3_process_event_entry(dwc, &event);
2708
2709                 /*
2710                  * FIXME we wrap around correctly to the next entry as
2711                  * almost all entries are 4 bytes in size. There is one
2712                  * entry which has 12 bytes which is a regular entry
2713                  * followed by 8 bytes data. ATM I don't know how
2714                  * things are organized if we get next to the a
2715                  * boundary so I worry about that once we try to handle
2716                  * that.
2717                  */
2718                 evt->lpos = (evt->lpos + 4) % DWC3_EVENT_BUFFERS_SIZE;
2719                 left -= 4;
2720
2721                 dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(buf), 4);
2722         }
2723
2724         evt->count = 0;
2725         evt->flags &= ~DWC3_EVENT_PENDING;
2726         ret = IRQ_HANDLED;
2727
2728         /* Unmask interrupt */
2729         reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(buf));
2730         reg &= ~DWC3_GEVNTSIZ_INTMASK;
2731         dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(buf), reg);
2732
2733         return ret;
2734 }
2735
2736 static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc)
2737 {
2738         struct dwc3 *dwc = _dwc;
2739         unsigned long flags;
2740         irqreturn_t ret = IRQ_NONE;
2741         int i;
2742
2743         spin_lock_irqsave(&dwc->lock, flags);
2744
2745         for (i = 0; i < dwc->num_event_buffers; i++)
2746                 ret |= dwc3_process_event_buf(dwc, i);
2747
2748         spin_unlock_irqrestore(&dwc->lock, flags);
2749
2750         return ret;
2751 }
2752
2753 static irqreturn_t dwc3_check_event_buf(struct dwc3 *dwc, u32 buf)
2754 {
2755         struct dwc3_event_buffer *evt;
2756         u32 count;
2757         u32 reg;
2758
2759         evt = dwc->ev_buffs[buf];
2760
2761         count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(buf));
2762         count &= DWC3_GEVNTCOUNT_MASK;
2763         if (!count)
2764                 return IRQ_NONE;
2765
2766         evt->count = count;
2767         evt->flags |= DWC3_EVENT_PENDING;
2768
2769         /* Mask interrupt */
2770         reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(buf));
2771         reg |= DWC3_GEVNTSIZ_INTMASK;
2772         dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(buf), reg);
2773
2774         return IRQ_WAKE_THREAD;
2775 }
2776
2777 static irqreturn_t dwc3_interrupt(int irq, void *_dwc)
2778 {
2779         struct dwc3                     *dwc = _dwc;
2780         int                             i;
2781         irqreturn_t                     ret = IRQ_NONE;
2782
2783         for (i = 0; i < dwc->num_event_buffers; i++) {
2784                 irqreturn_t status;
2785
2786                 status = dwc3_check_event_buf(dwc, i);
2787                 if (status == IRQ_WAKE_THREAD)
2788                         ret = status;
2789         }
2790
2791         return ret;
2792 }
2793
2794 /**
2795  * dwc3_gadget_init - Initializes gadget related registers
2796  * @dwc: pointer to our controller context structure
2797  *
2798  * Returns 0 on success otherwise negative errno.
2799  */
2800 int dwc3_gadget_init(struct dwc3 *dwc)
2801 {
2802         int                                     ret;
2803
2804         dwc->ctrl_req = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
2805                         &dwc->ctrl_req_addr, GFP_KERNEL);
2806         if (!dwc->ctrl_req) {
2807                 dev_err(dwc->dev, "failed to allocate ctrl request\n");
2808                 ret = -ENOMEM;
2809                 goto err0;
2810         }
2811
2812         dwc->ep0_trb = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2,
2813                         &dwc->ep0_trb_addr, GFP_KERNEL);
2814         if (!dwc->ep0_trb) {
2815                 dev_err(dwc->dev, "failed to allocate ep0 trb\n");
2816                 ret = -ENOMEM;
2817                 goto err1;
2818         }
2819
2820         dwc->setup_buf = kzalloc(DWC3_EP0_BOUNCE_SIZE, GFP_KERNEL);
2821         if (!dwc->setup_buf) {
2822                 ret = -ENOMEM;
2823                 goto err2;
2824         }
2825
2826         dwc->ep0_bounce = dma_alloc_coherent(dwc->dev,
2827                         DWC3_EP0_BOUNCE_SIZE, &dwc->ep0_bounce_addr,
2828                         GFP_KERNEL);
2829         if (!dwc->ep0_bounce) {
2830                 dev_err(dwc->dev, "failed to allocate ep0 bounce buffer\n");
2831                 ret = -ENOMEM;
2832                 goto err3;
2833         }
2834
2835         dwc->zlp_buf = kzalloc(DWC3_ZLP_BUF_SIZE, GFP_KERNEL);
2836         if (!dwc->zlp_buf) {
2837                 ret = -ENOMEM;
2838                 goto err4;
2839         }
2840
2841         dwc->gadget.ops                 = &dwc3_gadget_ops;
2842         dwc->gadget.speed               = USB_SPEED_UNKNOWN;
2843         dwc->gadget.sg_supported        = true;
2844         dwc->gadget.name                = "dwc3-gadget";
2845         dwc->gadget.is_otg              = dwc->dr_mode == USB_DR_MODE_OTG;
2846
2847         /*
2848          * FIXME We might be setting max_speed to <SUPER, however versions
2849          * <2.20a of dwc3 have an issue with metastability (documented
2850          * elsewhere in this driver) which tells us we can't set max speed to
2851          * anything lower than SUPER.
2852          *
2853          * Because gadget.max_speed is only used by composite.c and function
2854          * drivers (i.e. it won't go into dwc3's registers) we are allowing this
2855          * to happen so we avoid sending SuperSpeed Capability descriptor
2856          * together with our BOS descriptor as that could confuse host into
2857          * thinking we can handle super speed.
2858          *
2859          * Note that, in fact, we won't even support GetBOS requests when speed
2860          * is less than super speed because we don't have means, yet, to tell
2861          * composite.c that we are USB 2.0 + LPM ECN.
2862          */
2863         if (dwc->revision < DWC3_REVISION_220A)
2864                 dwc3_trace(trace_dwc3_gadget,
2865                                 "Changing max_speed on rev %08x\n",
2866                                 dwc->revision);
2867
2868         dwc->gadget.max_speed           = dwc->maximum_speed;
2869
2870         /*
2871          * Per databook, DWC3 needs buffer size to be aligned to MaxPacketSize
2872          * on ep out.
2873          */
2874         dwc->gadget.quirk_ep_out_aligned_size = true;
2875
2876         /*
2877          * REVISIT: Here we should clear all pending IRQs to be
2878          * sure we're starting from a well known location.
2879          */
2880
2881         ret = dwc3_gadget_init_endpoints(dwc);
2882         if (ret)
2883                 goto err5;
2884
2885         ret = usb_add_gadget_udc(dwc->dev, &dwc->gadget);
2886         if (ret) {
2887                 dev_err(dwc->dev, "failed to register udc\n");
2888                 goto err5;
2889         }
2890
2891         return 0;
2892
2893 err5:
2894         kfree(dwc->zlp_buf);
2895
2896 err4:
2897         dwc3_gadget_free_endpoints(dwc);
2898         dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
2899                         dwc->ep0_bounce, dwc->ep0_bounce_addr);
2900
2901 err3:
2902         kfree(dwc->setup_buf);
2903
2904 err2:
2905         dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
2906                         dwc->ep0_trb, dwc->ep0_trb_addr);
2907
2908 err1:
2909         dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
2910                         dwc->ctrl_req, dwc->ctrl_req_addr);
2911
2912 err0:
2913         return ret;
2914 }
2915
2916 /* -------------------------------------------------------------------------- */
2917
2918 void dwc3_gadget_exit(struct dwc3 *dwc)
2919 {
2920         usb_del_gadget_udc(&dwc->gadget);
2921
2922         dwc3_gadget_free_endpoints(dwc);
2923
2924         dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
2925                         dwc->ep0_bounce, dwc->ep0_bounce_addr);
2926
2927         kfree(dwc->setup_buf);
2928         kfree(dwc->zlp_buf);
2929
2930         dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
2931                         dwc->ep0_trb, dwc->ep0_trb_addr);
2932
2933         dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
2934                         dwc->ctrl_req, dwc->ctrl_req_addr);
2935 }
2936
2937 int dwc3_gadget_suspend(struct dwc3 *dwc)
2938 {
2939         if (!dwc->gadget_driver)
2940                 return 0;
2941
2942         if (dwc->pullups_connected) {
2943                 dwc3_gadget_disable_irq(dwc);
2944                 dwc3_gadget_run_stop(dwc, true, true);
2945         }
2946
2947         __dwc3_gadget_ep_disable(dwc->eps[0]);
2948         __dwc3_gadget_ep_disable(dwc->eps[1]);
2949
2950         dwc->dcfg = dwc3_readl(dwc->regs, DWC3_DCFG);
2951
2952         return 0;
2953 }
2954
2955 int dwc3_gadget_resume(struct dwc3 *dwc)
2956 {
2957         struct dwc3_ep          *dep;
2958         int                     ret;
2959
2960         if (!dwc->gadget_driver)
2961                 return 0;
2962
2963         /* Start with SuperSpeed Default */
2964         dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
2965
2966         dep = dwc->eps[0];
2967         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
2968                         false);
2969         if (ret)
2970                 goto err0;
2971
2972         dep = dwc->eps[1];
2973         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
2974                         false);
2975         if (ret)
2976                 goto err1;
2977
2978         /* begin to receive SETUP packets */
2979         dwc->ep0state = EP0_SETUP_PHASE;
2980         dwc3_ep0_out_start(dwc);
2981
2982         dwc3_writel(dwc->regs, DWC3_DCFG, dwc->dcfg);
2983
2984         if (dwc->pullups_connected) {
2985                 dwc3_gadget_enable_irq(dwc);
2986                 dwc3_gadget_run_stop(dwc, true, false);
2987         }
2988
2989         return 0;
2990
2991 err1:
2992         __dwc3_gadget_ep_disable(dwc->eps[0]);
2993
2994 err0:
2995         return ret;
2996 }