drivers/usb/gadget/udc/gr_udc.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * USB Peripheral Controller driver for Aeroflex Gaisler GRUSBDC.
   4  *
   5  * 2013 (c) Aeroflex Gaisler AB
   6  *
   7  * This driver supports GRUSBDC USB Device Controller cores available in the
   8  * GRLIB VHDL IP core library.
   9  *
  10  * Full documentation of the GRUSBDC core can be found here:
  11  * https://www.gaisler.com/products/grlib/grip.pdf
  12  *
  13  * Contributors:
  14  * - Andreas Larsson <andreas@gaisler.com>
  15  * - Marko Isomaki
  16  */
  17
  18 /*
  19  * A GRUSBDC core can have up to 16 IN endpoints and 16 OUT endpoints each
  20  * individually configurable to any of the four USB transfer types. This driver
  21  * only supports cores in DMA mode.
  22  */
  23
  24 #include <linux/kernel.h>
  25 #include <linux/module.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/slab.h>
  28 #include <linux/spinlock.h>
  29 #include <linux/errno.h>
  30 #include <linux/list.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/device.h>
  33 #include <linux/usb.h>
  34 #include <linux/usb/ch9.h>
  35 #include <linux/usb/gadget.h>
  36 #include <linux/dma-mapping.h>
  37 #include <linux/dmapool.h>
  38 #include <linux/debugfs.h>
  39 #include <linux/seq_file.h>
  40 #include <linux/of.h>
  41
  42 #include <asm/byteorder.h>
  43
  44 #include "gr_udc.h"
  45
  46 #define DRIVER_NAME     "gr_udc"
  47 #define DRIVER_DESC     "Aeroflex Gaisler GRUSBDC USB Peripheral Controller"
  48
  49 static const char driver_name[] = DRIVER_NAME;
  50
  51 #define gr_read32(x) (ioread32be((x)))
  52 #define gr_write32(x, v) (iowrite32be((v), (x)))
  53
  54 /* USB speed and corresponding string calculated from status register value */
  55 #define GR_SPEED(status) \
  56         ((status & GR_STATUS_SP) ? USB_SPEED_FULL : USB_SPEED_HIGH)
  57 #define GR_SPEED_STR(status) usb_speed_string(GR_SPEED(status))
  58
  59 /* Size of hardware buffer calculated from epctrl register value */
  60 #define GR_BUFFER_SIZE(epctrl)                                        \
  61         ((((epctrl) & GR_EPCTRL_BUFSZ_MASK) >> GR_EPCTRL_BUFSZ_POS) * \
  62          GR_EPCTRL_BUFSZ_SCALER)
  63
  64 /* ---------------------------------------------------------------------- */
  65 /* Debug printout functionality */
  66
  67 static const char * const gr_modestring[] = {"control", "iso", "bulk", "int"};
  68
  69 static const char *gr_ep0state_string(enum gr_ep0state state)
  70 {
  71         static const char *const names[] = {
  72                 [GR_EP0_DISCONNECT] = "disconnect",
  73                 [GR_EP0_SETUP] = "setup",
  74                 [GR_EP0_IDATA] = "idata",
  75                 [GR_EP0_ODATA] = "odata",
  76                 [GR_EP0_ISTATUS] = "istatus",
  77                 [GR_EP0_OSTATUS] = "ostatus",
  78                 [GR_EP0_STALL] = "stall",
  79                 [GR_EP0_SUSPEND] = "suspend",
  80         };
  81
  82         if (state < 0 || state >= ARRAY_SIZE(names))
  83                 return "UNKNOWN";
  84
  85         return names[state];
  86 }
  87
  88 #ifdef VERBOSE_DEBUG
  89
  90 static void gr_dbgprint_request(const char *str, struct gr_ep *ep,
  91                                 struct gr_request *req)
  92 {
  93         int buflen = ep->is_in ? req->req.length : req->req.actual;
  94         int rowlen = 32;
  95         int plen = min(rowlen, buflen);
  96
  97         dev_dbg(ep->dev->dev, "%s: 0x%p, %d bytes data%s:\n", str, req, buflen,
  98                 (buflen > plen ? " (truncated)" : ""));
  99         print_hex_dump_debug("   ", DUMP_PREFIX_NONE,
 100                              rowlen, 4, req->req.buf, plen, false);
 101 }
 102
 103 static void gr_dbgprint_devreq(struct gr_udc *dev, u8 type, u8 request,
 104                                u16 value, u16 index, u16 length)
 105 {
 106         dev_vdbg(dev->dev, "REQ: %02x.%02x v%04x i%04x l%04x\n",
 107                  type, request, value, index, length);
 108 }
 109 #else /* !VERBOSE_DEBUG */
 110
 111 static void gr_dbgprint_request(const char *str, struct gr_ep *ep,
 112                                 struct gr_request *req) {}
 113
 114 static void gr_dbgprint_devreq(struct gr_udc *dev, u8 type, u8 request,
 115                                u16 value, u16 index, u16 length) {}
 116
 117 #endif /* VERBOSE_DEBUG */
 118
 119 /* ---------------------------------------------------------------------- */
 120 /* Debugfs functionality */
 121
 122 #ifdef CONFIG_USB_GADGET_DEBUG_FS
 123
 124 static void gr_seq_ep_show(struct seq_file *seq, struct gr_ep *ep)
 125 {
 126         u32 epctrl = gr_read32(&ep->regs->epctrl);
 127         u32 epstat = gr_read32(&ep->regs->epstat);
 128         int mode = (epctrl & GR_EPCTRL_TT_MASK) >> GR_EPCTRL_TT_POS;
 129         struct gr_request *req;
 130
 131         seq_printf(seq, "%s:\n", ep->ep.name);
 132         seq_printf(seq, "  mode = %s\n", gr_modestring[mode]);
 133         seq_printf(seq, "  halted: %d\n", !!(epctrl & GR_EPCTRL_EH));
 134         seq_printf(seq, "  disabled: %d\n", !!(epctrl & GR_EPCTRL_ED));
 135         seq_printf(seq, "  valid: %d\n", !!(epctrl & GR_EPCTRL_EV));
 136         seq_printf(seq, "  dma_start = %d\n", ep->dma_start);
 137         seq_printf(seq, "  stopped = %d\n", ep->stopped);
 138         seq_printf(seq, "  wedged = %d\n", ep->wedged);
 139         seq_printf(seq, "  callback = %d\n", ep->callback);
 140         seq_printf(seq, "  maxpacket = %d\n", ep->ep.maxpacket);
 141         seq_printf(seq, "  maxpacket_limit = %d\n", ep->ep.maxpacket_limit);
 142         seq_printf(seq, "  bytes_per_buffer = %d\n", ep->bytes_per_buffer);
 143         if (mode == 1 || mode == 3)
 144                 seq_printf(seq, "  nt = %d\n",
 145                            (epctrl & GR_EPCTRL_NT_MASK) >> GR_EPCTRL_NT_POS);
 146
 147         seq_printf(seq, "  Buffer 0: %s %s%d\n",
 148                    epstat & GR_EPSTAT_B0 ? "valid" : "invalid",
 149                    epstat & GR_EPSTAT_BS ? " " : "selected ",
 150                    (epstat & GR_EPSTAT_B0CNT_MASK) >> GR_EPSTAT_B0CNT_POS);
 151         seq_printf(seq, "  Buffer 1: %s %s%d\n",
 152                    epstat & GR_EPSTAT_B1 ? "valid" : "invalid",
 153                    epstat & GR_EPSTAT_BS ? "selected " : " ",
 154                    (epstat & GR_EPSTAT_B1CNT_MASK) >> GR_EPSTAT_B1CNT_POS);
 155
 156         if (list_empty(&ep->queue)) {
 157                 seq_puts(seq, "  Queue: empty\n\n");
 158                 return;
 159         }
 160
 161         seq_puts(seq, "  Queue:\n");
 162         list_for_each_entry(req, &ep->queue, queue) {
 163                 struct gr_dma_desc *desc;
 164                 struct gr_dma_desc *next;
 165
 166                 seq_printf(seq, "    0x%p: 0x%p %d %d\n", req,
 167                            &req->req.buf, req->req.actual, req->req.length);
 168
 169                 next = req->first_desc;
 170                 do {
 171                         desc = next;
 172                         next = desc->next_desc;
 173                         seq_printf(seq, "    %c 0x%p (0x%08x): 0x%05x 0x%08x\n",
 174                                    desc == req->curr_desc ? 'c' : ' ',
 175                                    desc, desc->paddr, desc->ctrl, desc->data);
 176                 } while (desc != req->last_desc);
 177         }
 178         seq_puts(seq, "\n");
 179 }
 180
 181 static int gr_dfs_show(struct seq_file *seq, void *v)
 182 {
 183         struct gr_udc *dev = seq->private;
 184         u32 control = gr_read32(&dev->regs->control);
 185         u32 status = gr_read32(&dev->regs->status);
 186         struct gr_ep *ep;
 187
 188         seq_printf(seq, "usb state = %s\n",
 189                    usb_state_string(dev->gadget.state));
 190         seq_printf(seq, "address = %d\n",
 191                    (control & GR_CONTROL_UA_MASK) >> GR_CONTROL_UA_POS);
 192         seq_printf(seq, "speed = %s\n", GR_SPEED_STR(status));
 193         seq_printf(seq, "ep0state = %s\n", gr_ep0state_string(dev->ep0state));
 194         seq_printf(seq, "irq_enabled = %d\n", dev->irq_enabled);
 195         seq_printf(seq, "remote_wakeup = %d\n", dev->remote_wakeup);
 196         seq_printf(seq, "test_mode = %d\n", dev->test_mode);
 197         seq_puts(seq, "\n");
 198
 199         list_for_each_entry(ep, &dev->ep_list, ep_list)
 200                 gr_seq_ep_show(seq, ep);
 201
 202         return 0;
 203 }
 204 DEFINE_SHOW_ATTRIBUTE(gr_dfs);
 205
 206 static void gr_dfs_create(struct gr_udc *dev)
 207 {
 208         const char *name = "gr_udc_state";
 209         struct dentry *root;
 210
 211         root = debugfs_create_dir(dev_name(dev->dev), usb_debug_root);
 212         debugfs_create_file(name, 0444, root, dev, &gr_dfs_fops);
 213 }
 214
 215 static void gr_dfs_delete(struct gr_udc *dev)
 216 {
 217         debugfs_lookup_and_remove(dev_name(dev->dev), usb_debug_root);
 218 }
 219
 220 #else /* !CONFIG_USB_GADGET_DEBUG_FS */
 221
 222 static void gr_dfs_create(struct gr_udc *dev) {}
 223 static void gr_dfs_delete(struct gr_udc *dev) {}
 224
 225 #endif /* CONFIG_USB_GADGET_DEBUG_FS */
 226
 227 /* ---------------------------------------------------------------------- */
 228 /* DMA and request handling */
 229
 230 /* Allocates a new struct gr_dma_desc, sets paddr and zeroes the rest */
 231 static struct gr_dma_desc *gr_alloc_dma_desc(struct gr_ep *ep, gfp_t gfp_flags)
 232 {
 233         dma_addr_t paddr;
 234         struct gr_dma_desc *dma_desc;
 235
 236         dma_desc = dma_pool_zalloc(ep->dev->desc_pool, gfp_flags, &paddr);
 237         if (!dma_desc) {
 238                 dev_err(ep->dev->dev, "Could not allocate from DMA pool\n");
 239                 return NULL;
 240         }
 241
 242         dma_desc->paddr = paddr;
 243
 244         return dma_desc;
 245 }
 246
 247 static inline void gr_free_dma_desc(struct gr_udc *dev,
 248                                     struct gr_dma_desc *desc)
 249 {
 250         dma_pool_free(dev->desc_pool, desc, (dma_addr_t)desc->paddr);
 251 }
 252
 253 /* Frees the chain of struct gr_dma_desc for the given request */
 254 static void gr_free_dma_desc_chain(struct gr_udc *dev, struct gr_request *req)
 255 {
 256         struct gr_dma_desc *desc;
 257         struct gr_dma_desc *next;
 258
 259         next = req->first_desc;
 260         if (!next)
 261                 return;
 262
 263         do {
 264                 desc = next;
 265                 next = desc->next_desc;
 266                 gr_free_dma_desc(dev, desc);
 267         } while (desc != req->last_desc);
 268
 269         req->first_desc = NULL;
 270         req->curr_desc = NULL;
 271         req->last_desc = NULL;
 272 }
 273
 274 static void gr_ep0_setup(struct gr_udc *dev, struct gr_request *req);
 275
 276 /*
 277  * Frees allocated resources and calls the appropriate completion function/setup
 278  * package handler for a finished request.
 279  *
 280  * Must be called with dev->lock held and irqs disabled.
 281  */
 282 static void gr_finish_request(struct gr_ep *ep, struct gr_request *req,
 283                               int status)
 284         __releases(&dev->lock)
 285         __acquires(&dev->lock)
 286 {
 287         struct gr_udc *dev;
 288
 289         list_del_init(&req->queue);
 290
 291         if (likely(req->req.status == -EINPROGRESS))
 292                 req->req.status = status;
 293         else
 294                 status = req->req.status;
 295
 296         dev = ep->dev;
 297         usb_gadget_unmap_request(&dev->gadget, &req->req, ep->is_in);
 298         gr_free_dma_desc_chain(dev, req);
 299
 300         if (ep->is_in) { /* For OUT, req->req.actual gets updated bit by bit */
 301                 req->req.actual = req->req.length;
 302         } else if (req->oddlen && req->req.actual > req->evenlen) {
 303                 /*
 304                  * Copy to user buffer in this case where length was not evenly
 305                  * divisible by ep->ep.maxpacket and the last descriptor was
 306                  * actually used.
 307                  */
 308                 char *buftail = ((char *)req->req.buf + req->evenlen);
 309
 310                 memcpy(buftail, ep->tailbuf, req->oddlen);
 311
 312                 if (req->req.actual > req->req.length) {
 313                         /* We got more data than was requested */
 314                         dev_dbg(ep->dev->dev, "Overflow for ep %s\n",
 315                                 ep->ep.name);
 316                         gr_dbgprint_request("OVFL", ep, req);
 317                         req->req.status = -EOVERFLOW;
 318                 }
 319         }
 320
 321         if (!status) {
 322                 if (ep->is_in)
 323                         gr_dbgprint_request("SENT", ep, req);
 324                 else
 325                         gr_dbgprint_request("RECV", ep, req);
 326         }
 327
 328         /* Prevent changes to ep->queue during callback */
 329         ep->callback = 1;
 330         if (req == dev->ep0reqo && !status) {
 331                 if (req->setup)
 332                         gr_ep0_setup(dev, req);
 333                 else
 334                         dev_err(dev->dev,
 335                                 "Unexpected non setup packet on ep0in\n");
 336         } else if (req->req.complete) {
 337                 spin_unlock(&dev->lock);
 338
 339                 usb_gadget_giveback_request(&ep->ep, &req->req);
 340
 341                 spin_lock(&dev->lock);
 342         }
 343         ep->callback = 0;
 344 }
 345
 346 static struct usb_request *gr_alloc_request(struct usb_ep *_ep, gfp_t gfp_flags)
 347 {
 348         struct gr_request *req;
 349
 350         req = kzalloc(sizeof(*req), gfp_flags);
 351         if (!req)
 352                 return NULL;
 353
 354         INIT_LIST_HEAD(&req->queue);
 355
 356         return &req->req;
 357 }
 358
 359 /*
 360  * Starts DMA for endpoint ep if there are requests in the queue.
 361  *
 362  * Must be called with dev->lock held and with !ep->stopped.
 363  */
 364 static void gr_start_dma(struct gr_ep *ep)
 365 {
 366         struct gr_request *req;
 367         u32 dmactrl;
 368
 369         if (list_empty(&ep->queue)) {
 370                 ep->dma_start = 0;
 371                 return;
 372         }
 373
 374         req = list_first_entry(&ep->queue, struct gr_request, queue);
 375
 376         /* A descriptor should already have been allocated */
 377         BUG_ON(!req->curr_desc);
 378
 379         /*
 380          * The DMA controller can not handle smaller OUT buffers than
 381          * ep->ep.maxpacket. It could lead to buffer overruns if an unexpectedly
 382          * long packet are received. Therefore an internal bounce buffer gets
 383          * used when such a request gets enabled.
 384          */
 385         if (!ep->is_in && req->oddlen)
 386                 req->last_desc->data = ep->tailbuf_paddr;
 387
 388         wmb(); /* Make sure all is settled before handing it over to DMA */
 389
 390         /* Set the descriptor pointer in the hardware */
 391         gr_write32(&ep->regs->dmaaddr, req->curr_desc->paddr);
 392
 393         /* Announce available descriptors */
 394         dmactrl = gr_read32(&ep->regs->dmactrl);
 395         gr_write32(&ep->regs->dmactrl, dmactrl | GR_DMACTRL_DA);
 396
 397         ep->dma_start = 1;
 398 }
 399
 400 /*
 401  * Finishes the first request in the ep's queue and, if available, starts the
 402  * next request in queue.
 403  *
 404  * Must be called with dev->lock held, irqs disabled and with !ep->stopped.
 405  */
 406 static void gr_dma_advance(struct gr_ep *ep, int status)
 407 {
 408         struct gr_request *req;
 409
 410         req = list_first_entry(&ep->queue, struct gr_request, queue);
 411         gr_finish_request(ep, req, status);
 412         gr_start_dma(ep); /* Regardless of ep->dma_start */
 413 }
 414
 415 /*
 416  * Abort DMA for an endpoint. Sets the abort DMA bit which causes an ongoing DMA
 417  * transfer to be canceled and clears GR_DMACTRL_DA.
 418  *
 419  * Must be called with dev->lock held.
 420  */
 421 static void gr_abort_dma(struct gr_ep *ep)
 422 {
 423         u32 dmactrl;
 424
 425         dmactrl = gr_read32(&ep->regs->dmactrl);
 426         gr_write32(&ep->regs->dmactrl, dmactrl | GR_DMACTRL_AD);
 427 }
 428
 429 /*
 430  * Allocates and sets up a struct gr_dma_desc and putting it on the descriptor
 431  * chain.
 432  *
 433  * Size is not used for OUT endpoints. Hardware can not be instructed to handle
 434  * smaller buffer than MAXPL in the OUT direction.
 435  */
 436 static int gr_add_dma_desc(struct gr_ep *ep, struct gr_request *req,
 437                            dma_addr_t data, unsigned size, gfp_t gfp_flags)
 438 {
 439         struct gr_dma_desc *desc;
 440
 441         desc = gr_alloc_dma_desc(ep, gfp_flags);
 442         if (!desc)
 443                 return -ENOMEM;
 444
 445         desc->data = data;
 446         if (ep->is_in)
 447                 desc->ctrl =
 448                         (GR_DESC_IN_CTRL_LEN_MASK & size) | GR_DESC_IN_CTRL_EN;
 449         else
 450                 desc->ctrl = GR_DESC_OUT_CTRL_IE;
 451
 452         if (!req->first_desc) {
 453                 req->first_desc = desc;
 454                 req->curr_desc = desc;
 455         } else {
 456                 req->last_desc->next_desc = desc;
 457                 req->last_desc->next = desc->paddr;
 458                 req->last_desc->ctrl |= GR_DESC_OUT_CTRL_NX;
 459         }
 460         req->last_desc = desc;
 461
 462         return 0;
 463 }
 464
 465 /*
 466  * Sets up a chain of struct gr_dma_descriptors pointing to buffers that
 467  * together covers req->req.length bytes of the buffer at DMA address
 468  * req->req.dma for the OUT direction.
 469  *
 470  * The first descriptor in the chain is enabled, the rest disabled. The
 471  * interrupt handler will later enable them one by one when needed so we can
 472  * find out when the transfer is finished. For OUT endpoints, all descriptors
 473  * therefore generate interrutps.
 474  */
 475 static int gr_setup_out_desc_list(struct gr_ep *ep, struct gr_request *req,
 476                                   gfp_t gfp_flags)
 477 {
 478         u16 bytes_left; /* Bytes left to provide descriptors for */
 479         u16 bytes_used; /* Bytes accommodated for */
 480         int ret = 0;
 481
 482         req->first_desc = NULL; /* Signals that no allocation is done yet */
 483         bytes_left = req->req.length;
 484         bytes_used = 0;
 485         while (bytes_left > 0) {
 486                 dma_addr_t start = req->req.dma + bytes_used;
 487                 u16 size = min(bytes_left, ep->bytes_per_buffer);
 488
 489                 if (size < ep->bytes_per_buffer) {
 490                         /* Prepare using bounce buffer */
 491                         req->evenlen = req->req.length - bytes_left;
 492                         req->oddlen = size;
 493                 }
 494
 495                 ret = gr_add_dma_desc(ep, req, start, size, gfp_flags);
 496                 if (ret)
 497                         goto alloc_err;
 498
 499                 bytes_left -= size;
 500                 bytes_used += size;
 501         }
 502
 503         req->first_desc->ctrl |= GR_DESC_OUT_CTRL_EN;
 504
 505         return 0;
 506
 507 alloc_err:
 508         gr_free_dma_desc_chain(ep->dev, req);
 509
 510         return ret;
 511 }
 512
 513 /*
 514  * Sets up a chain of struct gr_dma_descriptors pointing to buffers that
 515  * together covers req->req.length bytes of the buffer at DMA address
 516  * req->req.dma for the IN direction.
 517  *
 518  * When more data is provided than the maximum payload size, the hardware splits
 519  * this up into several payloads automatically. Moreover, ep->bytes_per_buffer
 520  * is always set to a multiple of the maximum payload (restricted to the valid
 521  * number of maximum payloads during high bandwidth isochronous or interrupt
 522  * transfers)
 523  *
 524  * All descriptors are enabled from the beginning and we only generate an
 525  * interrupt for the last one indicating that the entire request has been pushed
 526  * to hardware.
 527  */
 528 static int gr_setup_in_desc_list(struct gr_ep *ep, struct gr_request *req,
 529                                  gfp_t gfp_flags)
 530 {
 531         u16 bytes_left; /* Bytes left in req to provide descriptors for */
 532         u16 bytes_used; /* Bytes in req accommodated for */
 533         int ret = 0;
 534
 535         req->first_desc = NULL; /* Signals that no allocation is done yet */
 536         bytes_left = req->req.length;
 537         bytes_used = 0;
 538         do { /* Allow for zero length packets */
 539                 dma_addr_t start = req->req.dma + bytes_used;
 540                 u16 size = min(bytes_left, ep->bytes_per_buffer);
 541
 542                 ret = gr_add_dma_desc(ep, req, start, size, gfp_flags);
 543                 if (ret)
 544                         goto alloc_err;
 545
 546                 bytes_left -= size;
 547                 bytes_used += size;
 548         } while (bytes_left > 0);
 549
 550         /*
 551          * Send an extra zero length packet to indicate that no more data is
 552          * available when req->req.zero is set and the data length is even
 553          * multiples of ep->ep.maxpacket.
 554          */
 555         if (req->req.zero && (req->req.length % ep->ep.maxpacket == 0)) {
 556                 ret = gr_add_dma_desc(ep, req, 0, 0, gfp_flags);
 557                 if (ret)
 558                         goto alloc_err;
 559         }
 560
 561         /*
 562          * For IN packets we only want to know when the last packet has been
 563          * transmitted (not just put into internal buffers).
 564          */
 565         req->last_desc->ctrl |= GR_DESC_IN_CTRL_PI;
 566
 567         return 0;
 568
 569 alloc_err:
 570         gr_free_dma_desc_chain(ep->dev, req);
 571
 572         return ret;
 573 }
 574
 575 /* Must be called with dev->lock held */
 576 static int gr_queue(struct gr_ep *ep, struct gr_request *req, gfp_t gfp_flags)
 577 {
 578         struct gr_udc *dev = ep->dev;
 579         int ret;
 580
 581         if (unlikely(!ep->ep.desc && ep->num != 0)) {
 582                 dev_err(dev->dev, "No ep descriptor for %s\n", ep->ep.name);
 583                 return -EINVAL;
 584         }
 585
 586         if (unlikely(!req->req.buf || !list_empty(&req->queue))) {
 587                 dev_err(dev->dev,
 588                         "Invalid request for %s: buf=%p list_empty=%d\n",
 589                         ep->ep.name, req->req.buf, list_empty(&req->queue));
 590                 return -EINVAL;
 591         }
 592
 593         if (unlikely(!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)) {
 594                 dev_err(dev->dev, "-ESHUTDOWN");
 595                 return -ESHUTDOWN;
 596         }
 597
 598         /* Can't touch registers when suspended */
 599         if (dev->ep0state == GR_EP0_SUSPEND) {
 600                 dev_err(dev->dev, "-EBUSY");
 601                 return -EBUSY;
 602         }
 603
 604         /* Set up DMA mapping in case the caller didn't */
 605         ret = usb_gadget_map_request(&dev->gadget, &req->req, ep->is_in);
 606         if (ret) {
 607                 dev_err(dev->dev, "usb_gadget_map_request");
 608                 return ret;
 609         }
 610
 611         if (ep->is_in)
 612                 ret = gr_setup_in_desc_list(ep, req, gfp_flags);
 613         else
 614                 ret = gr_setup_out_desc_list(ep, req, gfp_flags);
 615         if (ret)
 616                 return ret;
 617
 618         req->req.status = -EINPROGRESS;
 619         req->req.actual = 0;
 620         list_add_tail(&req->queue, &ep->queue);
 621
 622         /* Start DMA if not started, otherwise interrupt handler handles it */
 623         if (!ep->dma_start && likely(!ep->stopped))
 624                 gr_start_dma(ep);
 625
 626         return 0;
 627 }
 628
 629 /*
 630  * Queue a request from within the driver.
 631  *
 632  * Must be called with dev->lock held.
 633  */
 634 static inline int gr_queue_int(struct gr_ep *ep, struct gr_request *req,
 635                                gfp_t gfp_flags)
 636 {
 637         if (ep->is_in)
 638                 gr_dbgprint_request("RESP", ep, req);
 639
 640         return gr_queue(ep, req, gfp_flags);
 641 }
 642
 643 /* ---------------------------------------------------------------------- */
 644 /* General helper functions */
 645
 646 /*
 647  * Dequeue ALL requests.
 648  *
 649  * Must be called with dev->lock held and irqs disabled.
 650  */
 651 static void gr_ep_nuke(struct gr_ep *ep)
 652 {
 653         struct gr_request *req;
 654
 655         ep->stopped = 1;
 656         ep->dma_start = 0;
 657         gr_abort_dma(ep);
 658
 659         while (!list_empty(&ep->queue)) {
 660                 req = list_first_entry(&ep->queue, struct gr_request, queue);
 661                 gr_finish_request(ep, req, -ESHUTDOWN);
 662         }
 663 }
 664
 665 /*
 666  * Reset the hardware state of this endpoint.
 667  *
 668  * Must be called with dev->lock held.
 669  */
 670 static void gr_ep_reset(struct gr_ep *ep)
 671 {
 672         gr_write32(&ep->regs->epctrl, 0);
 673         gr_write32(&ep->regs->dmactrl, 0);
 674
 675         ep->ep.maxpacket = MAX_CTRL_PL_SIZE;
 676         ep->ep.desc = NULL;
 677         ep->stopped = 1;
 678         ep->dma_start = 0;
 679 }
 680
 681 /*
 682  * Generate STALL on ep0in/out.
 683  *
 684  * Must be called with dev->lock held.
 685  */
 686 static void gr_control_stall(struct gr_udc *dev)
 687 {
 688         u32 epctrl;
 689
 690         epctrl = gr_read32(&dev->epo[0].regs->epctrl);
 691         gr_write32(&dev->epo[0].regs->epctrl, epctrl | GR_EPCTRL_CS);
 692         epctrl = gr_read32(&dev->epi[0].regs->epctrl);
 693         gr_write32(&dev->epi[0].regs->epctrl, epctrl | GR_EPCTRL_CS);
 694
 695         dev->ep0state = GR_EP0_STALL;
 696 }
 697
 698 /*
 699  * Halts, halts and wedges, or clears halt for an endpoint.
 700  *
 701  * Must be called with dev->lock held.
 702  */
 703 static int gr_ep_halt_wedge(struct gr_ep *ep, int halt, int wedge, int fromhost)
 704 {
 705         u32 epctrl;
 706         int retval = 0;
 707
 708         if (ep->num && !ep->ep.desc)
 709                 return -EINVAL;
 710
 711         if (ep->num && ep->ep.desc->bmAttributes == USB_ENDPOINT_XFER_ISOC)
 712                 return -EOPNOTSUPP;
 713
 714         /* Never actually halt ep0, and therefore never clear halt for ep0 */
 715         if (!ep->num) {
 716                 if (halt && !fromhost) {
 717                         /* ep0 halt from gadget - generate protocol stall */
 718                         gr_control_stall(ep->dev);
 719                         dev_dbg(ep->dev->dev, "EP: stall ep0\n");
 720                         return 0;
 721                 }
 722                 return -EINVAL;
 723         }
 724
 725         dev_dbg(ep->dev->dev, "EP: %s halt %s\n",
 726                 (halt ? (wedge ? "wedge" : "set") : "clear"), ep->ep.name);
 727
 728         epctrl = gr_read32(&ep->regs->epctrl);
 729         if (halt) {
 730                 /* Set HALT */
 731                 gr_write32(&ep->regs->epctrl, epctrl | GR_EPCTRL_EH);
 732                 ep->stopped = 1;
 733                 if (wedge)
 734                         ep->wedged = 1;
 735         } else {
 736                 gr_write32(&ep->regs->epctrl, epctrl & ~GR_EPCTRL_EH);
 737                 ep->stopped = 0;
 738                 ep->wedged = 0;
 739
 740                 /* Things might have been queued up in the meantime */
 741                 if (!ep->dma_start)
 742                         gr_start_dma(ep);
 743         }
 744
 745         return retval;
 746 }
 747
 748 /* Must be called with dev->lock held */
 749 static inline void gr_set_ep0state(struct gr_udc *dev, enum gr_ep0state value)
 750 {
 751         if (dev->ep0state != value)
 752                 dev_vdbg(dev->dev, "STATE:  ep0state=%s\n",
 753                          gr_ep0state_string(value));
 754         dev->ep0state = value;
 755 }
 756
 757 /*
 758  * Should only be called when endpoints can not generate interrupts.
 759  *
 760  * Must be called with dev->lock held.
 761  */
 762 static void gr_disable_interrupts_and_pullup(struct gr_udc *dev)
 763 {
 764         gr_write32(&dev->regs->control, 0);
 765         wmb(); /* Make sure that we do not deny one of our interrupts */
 766         dev->irq_enabled = 0;
 767 }
 768
 769 /*
 770  * Stop all device activity and disable data line pullup.
 771  *
 772  * Must be called with dev->lock held and irqs disabled.
 773  */
 774 static void gr_stop_activity(struct gr_udc *dev)
 775 {
 776         struct gr_ep *ep;
 777
 778         list_for_each_entry(ep, &dev->ep_list, ep_list)
 779                 gr_ep_nuke(ep);
 780
 781         gr_disable_interrupts_and_pullup(dev);
 782
 783         gr_set_ep0state(dev, GR_EP0_DISCONNECT);
 784         usb_gadget_set_state(&dev->gadget, USB_STATE_NOTATTACHED);
 785 }
 786
 787 /* ---------------------------------------------------------------------- */
 788 /* ep0 setup packet handling */
 789
 790 static void gr_ep0_testmode_complete(struct usb_ep *_ep,
 791                                      struct usb_request *_req)
 792 {
 793         struct gr_ep *ep;
 794         struct gr_udc *dev;
 795         u32 control;
 796
 797         ep = container_of(_ep, struct gr_ep, ep);
 798         dev = ep->dev;
 799
 800         spin_lock(&dev->lock);
 801
 802         control = gr_read32(&dev->regs->control);
 803         control |= GR_CONTROL_TM | (dev->test_mode << GR_CONTROL_TS_POS);
 804         gr_write32(&dev->regs->control, control);
 805
 806         spin_unlock(&dev->lock);
 807 }
 808
 809 static void gr_ep0_dummy_complete(struct usb_ep *_ep, struct usb_request *_req)
 810 {
 811         /* Nothing needs to be done here */
 812 }
 813
 814 /*
 815  * Queue a response on ep0in.
 816  *
 817  * Must be called with dev->lock held.
 818  */
 819 static int gr_ep0_respond(struct gr_udc *dev, u8 *buf, int length,
 820                           void (*complete)(struct usb_ep *ep,
 821                                            struct usb_request *req))
 822 {
 823         u8 *reqbuf = dev->ep0reqi->req.buf;
 824         int status;
 825         int i;
 826
 827         for (i = 0; i < length; i++)
 828                 reqbuf[i] = buf[i];
 829         dev->ep0reqi->req.length = length;
 830         dev->ep0reqi->req.complete = complete;
 831
 832         status = gr_queue_int(&dev->epi[0], dev->ep0reqi, GFP_ATOMIC);
 833         if (status < 0)
 834                 dev_err(dev->dev,
 835                         "Could not queue ep0in setup response: %d\n", status);
 836
 837         return status;
 838 }
 839
 840 /*
 841  * Queue a 2 byte response on ep0in.
 842  *
 843  * Must be called with dev->lock held.
 844  */
 845 static inline int gr_ep0_respond_u16(struct gr_udc *dev, u16 response)
 846 {
 847         __le16 le_response = cpu_to_le16(response);
 848
 849         return gr_ep0_respond(dev, (u8 *)&le_response, 2,
 850                               gr_ep0_dummy_complete);
 851 }
 852
 853 /*
 854  * Queue a ZLP response on ep0in.
 855  *
 856  * Must be called with dev->lock held.
 857  */
 858 static inline int gr_ep0_respond_empty(struct gr_udc *dev)
 859 {
 860         return gr_ep0_respond(dev, NULL, 0, gr_ep0_dummy_complete);
 861 }
 862
 863 /*
 864  * This is run when a SET_ADDRESS request is received. First writes
 865  * the new address to the control register which is updated internally
 866  * when the next IN packet is ACKED.
 867  *
 868  * Must be called with dev->lock held.
 869  */
 870 static void gr_set_address(struct gr_udc *dev, u8 address)
 871 {
 872         u32 control;
 873
 874         control = gr_read32(&dev->regs->control) & ~GR_CONTROL_UA_MASK;
 875         control |= (address << GR_CONTROL_UA_POS) & GR_CONTROL_UA_MASK;
 876         control |= GR_CONTROL_SU;
 877         gr_write32(&dev->regs->control, control);
 878 }
 879
 880 /*
 881  * Returns negative for STALL, 0 for successful handling and positive for
 882  * delegation.
 883  *
 884  * Must be called with dev->lock held.
 885  */
 886 static int gr_device_request(struct gr_udc *dev, u8 type, u8 request,
 887                              u16 value, u16 index)
 888 {
 889         u16 response;
 890         u8 test;
 891
 892         switch (request) {
 893         case USB_REQ_SET_ADDRESS:
 894                 dev_dbg(dev->dev, "STATUS: address %d\n", value & 0xff);
 895                 gr_set_address(dev, value & 0xff);
 896                 if (value)
 897                         usb_gadget_set_state(&dev->gadget, USB_STATE_ADDRESS);
 898                 else
 899                         usb_gadget_set_state(&dev->gadget, USB_STATE_DEFAULT);
 900                 return gr_ep0_respond_empty(dev);
 901
 902         case USB_REQ_GET_STATUS:
 903                 /* Self powered | remote wakeup */
 904                 response = 0x0001 | (dev->remote_wakeup ? 0x0002 : 0);
 905                 return gr_ep0_respond_u16(dev, response);
 906
 907         case USB_REQ_SET_FEATURE:
 908                 switch (value) {
 909                 case USB_DEVICE_REMOTE_WAKEUP:
 910                         /* Allow remote wakeup */
 911                         dev->remote_wakeup = 1;
 912                         return gr_ep0_respond_empty(dev);
 913
 914                 case USB_DEVICE_TEST_MODE:
 915                         /* The hardware does not support USB_TEST_FORCE_ENABLE */
 916                         test = index >> 8;
 917                         if (test >= USB_TEST_J && test <= USB_TEST_PACKET) {
 918                                 dev->test_mode = test;
 919                                 return gr_ep0_respond(dev, NULL, 0,
 920                                                       gr_ep0_testmode_complete);
 921                         }
 922                 }
 923                 break;
 924
 925         case USB_REQ_CLEAR_FEATURE:
 926                 switch (value) {
 927                 case USB_DEVICE_REMOTE_WAKEUP:
 928                         /* Disallow remote wakeup */
 929                         dev->remote_wakeup = 0;
 930                         return gr_ep0_respond_empty(dev);
 931                 }
 932                 break;
 933         }
 934
 935         return 1; /* Delegate the rest */
 936 }
 937
 938 /*
 939  * Returns negative for STALL, 0 for successful handling and positive for
 940  * delegation.
 941  *
 942  * Must be called with dev->lock held.
 943  */
 944 static int gr_interface_request(struct gr_udc *dev, u8 type, u8 request,
 945                                 u16 value, u16 index)
 946 {
 947         if (dev->gadget.state != USB_STATE_CONFIGURED)
 948                 return -1;
 949
 950         /*
 951          * Should return STALL for invalid interfaces, but udc driver does not
 952          * know anything about that. However, many gadget drivers do not handle
 953          * GET_STATUS so we need to take care of that.
 954          */
 955
 956         switch (request) {
 957         case USB_REQ_GET_STATUS:
 958                 return gr_ep0_respond_u16(dev, 0x0000);
 959
 960         case USB_REQ_SET_FEATURE:
 961         case USB_REQ_CLEAR_FEATURE:
 962                 /*
 963                  * No possible valid standard requests. Still let gadget drivers
 964                  * have a go at it.
 965                  */
 966                 break;
 967         }
 968
 969         return 1; /* Delegate the rest */
 970 }
 971
 972 /*
 973  * Returns negative for STALL, 0 for successful handling and positive for
 974  * delegation.
 975  *
 976  * Must be called with dev->lock held.
 977  */
 978 static int gr_endpoint_request(struct gr_udc *dev, u8 type, u8 request,
 979                                u16 value, u16 index)
 980 {
 981         struct gr_ep *ep;
 982         int status;
 983         int halted;
 984         u8 epnum = index & USB_ENDPOINT_NUMBER_MASK;
 985         u8 is_in = index & USB_ENDPOINT_DIR_MASK;
 986
 987         if ((is_in && epnum >= dev->nepi) || (!is_in && epnum >= dev->nepo))
 988                 return -1;
 989
 990         if (dev->gadget.state != USB_STATE_CONFIGURED && epnum != 0)
 991                 return -1;
 992
 993         ep = (is_in ? &dev->epi[epnum] : &dev->epo[epnum]);
 994
 995         switch (request) {
 996         case USB_REQ_GET_STATUS:
 997                 halted = gr_read32(&ep->regs->epctrl) & GR_EPCTRL_EH;
 998                 return gr_ep0_respond_u16(dev, halted ? 0x0001 : 0);
 999
1000         case USB_REQ_SET_FEATURE:
1001                 switch (value) {
1002                 case USB_ENDPOINT_HALT:
1003                         status = gr_ep_halt_wedge(ep, 1, 0, 1);
1004                         if (status >= 0)
1005                                 status = gr_ep0_respond_empty(dev);
1006                         return status;
1007                 }
1008                 break;
1009
1010         case USB_REQ_CLEAR_FEATURE:
1011                 switch (value) {
1012                 case USB_ENDPOINT_HALT:
1013                         if (ep->wedged)
1014                                 return -1;
1015                         status = gr_ep_halt_wedge(ep, 0, 0, 1);
1016                         if (status >= 0)
1017                                 status = gr_ep0_respond_empty(dev);
1018                         return status;
1019                 }
1020                 break;
1021         }
1022
1023         return 1; /* Delegate the rest */
1024 }
1025
1026 /* Must be called with dev->lock held */
1027 static void gr_ep0out_requeue(struct gr_udc *dev)
1028 {
1029         int ret = gr_queue_int(&dev->epo[0], dev->ep0reqo, GFP_ATOMIC);
1030
1031         if (ret)
1032                 dev_err(dev->dev, "Could not queue ep0out setup request: %d\n",
1033                         ret);
1034 }
1035
1036 /*
1037  * The main function dealing with setup requests on ep0.
1038  *
1039  * Must be called with dev->lock held and irqs disabled
1040  */
1041 static void gr_ep0_setup(struct gr_udc *dev, struct gr_request *req)
1042         __releases(&dev->lock)
1043         __acquires(&dev->lock)
1044 {
1045         union {
1046                 struct usb_ctrlrequest ctrl;
1047                 u8 raw[8];
1048                 u32 word[2];
1049         } u;
1050         u8 type;
1051         u8 request;
1052         u16 value;
1053         u16 index;
1054         u16 length;
1055         int i;
1056         int status;
1057
1058         /* Restore from ep0 halt */
1059         if (dev->ep0state == GR_EP0_STALL) {
1060                 gr_set_ep0state(dev, GR_EP0_SETUP);
1061                 if (!req->req.actual)
1062                         goto out;
1063         }
1064
1065         if (dev->ep0state == GR_EP0_ISTATUS) {
1066                 gr_set_ep0state(dev, GR_EP0_SETUP);
1067                 if (req->req.actual > 0)
1068                         dev_dbg(dev->dev,
1069                                 "Unexpected setup packet at state %s\n",
1070                                 gr_ep0state_string(GR_EP0_ISTATUS));
1071                 else
1072                         goto out; /* Got expected ZLP */
1073         } else if (dev->ep0state != GR_EP0_SETUP) {
1074                 dev_info(dev->dev,
1075                          "Unexpected ep0out request at state %s - stalling\n",
1076                          gr_ep0state_string(dev->ep0state));
1077                 gr_control_stall(dev);
1078                 gr_set_ep0state(dev, GR_EP0_SETUP);
1079                 goto out;
1080         } else if (!req->req.actual) {
1081                 dev_dbg(dev->dev, "Unexpected ZLP at state %s\n",
1082                         gr_ep0state_string(dev->ep0state));
1083                 goto out;
1084         }
1085
1086         /* Handle SETUP packet */
1087         for (i = 0; i < req->req.actual; i++)
1088                 u.raw[i] = ((u8 *)req->req.buf)[i];
1089
1090         type = u.ctrl.bRequestType;
1091         request = u.ctrl.bRequest;
1092         value = le16_to_cpu(u.ctrl.wValue);
1093         index = le16_to_cpu(u.ctrl.wIndex);
1094         length = le16_to_cpu(u.ctrl.wLength);
1095
1096         gr_dbgprint_devreq(dev, type, request, value, index, length);
1097
1098         /* Check for data stage */
1099         if (length) {
1100                 if (type & USB_DIR_IN)
1101                         gr_set_ep0state(dev, GR_EP0_IDATA);
1102                 else
1103                         gr_set_ep0state(dev, GR_EP0_ODATA);
1104         }
1105
1106         status = 1; /* Positive status flags delegation */
1107         if ((type & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
1108                 switch (type & USB_RECIP_MASK) {
1109                 case USB_RECIP_DEVICE:
1110                         status = gr_device_request(dev, type, request,
1111                                                    value, index);
1112                         break;
1113                 case USB_RECIP_ENDPOINT:
1114                         status =  gr_endpoint_request(dev, type, request,
1115                                                       value, index);
1116                         break;
1117                 case USB_RECIP_INTERFACE:
1118                         status = gr_interface_request(dev, type, request,
1119                                                       value, index);
1120                         break;
1121                 }
1122         }
1123
1124         if (status > 0) {
1125                 spin_unlock(&dev->lock);
1126
1127                 dev_vdbg(dev->dev, "DELEGATE\n");
1128                 status = dev->driver->setup(&dev->gadget, &u.ctrl);
1129
1130                 spin_lock(&dev->lock);
1131         }
1132
1133         /* Generate STALL on both ep0out and ep0in if requested */
1134         if (unlikely(status < 0)) {
1135                 dev_vdbg(dev->dev, "STALL\n");
1136                 gr_control_stall(dev);
1137         }
1138
1139         if ((type & USB_TYPE_MASK) == USB_TYPE_STANDARD &&
1140             request == USB_REQ_SET_CONFIGURATION) {
1141                 if (!value) {
1142                         dev_dbg(dev->dev, "STATUS: deconfigured\n");
1143                         usb_gadget_set_state(&dev->gadget, USB_STATE_ADDRESS);
1144                 } else if (status >= 0) {
1145                         /* Not configured unless gadget OK:s it */
1146                         dev_dbg(dev->dev, "STATUS: configured: %d\n", value);
1147                         usb_gadget_set_state(&dev->gadget,
1148                                              USB_STATE_CONFIGURED);
1149                 }
1150         }
1151
1152         /* Get ready for next stage */
1153         if (dev->ep0state == GR_EP0_ODATA)
1154                 gr_set_ep0state(dev, GR_EP0_OSTATUS);
1155         else if (dev->ep0state == GR_EP0_IDATA)
1156                 gr_set_ep0state(dev, GR_EP0_ISTATUS);
1157         else
1158                 gr_set_ep0state(dev, GR_EP0_SETUP);
1159
1160 out:
1161         gr_ep0out_requeue(dev);
1162 }
1163
1164 /* ---------------------------------------------------------------------- */
1165 /* VBUS and USB reset handling */
1166
1167 /* Must be called with dev->lock held and irqs disabled  */
1168 static void gr_vbus_connected(struct gr_udc *dev, u32 status)
1169 {
1170         u32 control;
1171
1172         dev->gadget.speed = GR_SPEED(status);
1173         usb_gadget_set_state(&dev->gadget, USB_STATE_POWERED);
1174
1175         /* Turn on full interrupts and pullup */
1176         control = (GR_CONTROL_SI | GR_CONTROL_UI | GR_CONTROL_VI |
1177                    GR_CONTROL_SP | GR_CONTROL_EP);
1178         gr_write32(&dev->regs->control, control);
1179 }
1180
1181 /* Must be called with dev->lock held */
1182 static void gr_enable_vbus_detect(struct gr_udc *dev)
1183 {
1184         u32 status;
1185
1186         dev->irq_enabled = 1;
1187         wmb(); /* Make sure we do not ignore an interrupt */
1188         gr_write32(&dev->regs->control, GR_CONTROL_VI);
1189
1190         /* Take care of the case we are already plugged in at this point */
1191         status = gr_read32(&dev->regs->status);
1192         if (status & GR_STATUS_VB)
1193                 gr_vbus_connected(dev, status);
1194 }
1195
1196 /* Must be called with dev->lock held and irqs disabled */
1197 static void gr_vbus_disconnected(struct gr_udc *dev)
1198 {
1199         gr_stop_activity(dev);
1200
1201         /* Report disconnect */
1202         if (dev->driver && dev->driver->disconnect) {
1203                 spin_unlock(&dev->lock);
1204
1205                 dev->driver->disconnect(&dev->gadget);
1206
1207                 spin_lock(&dev->lock);
1208         }
1209
1210         gr_enable_vbus_detect(dev);
1211 }
1212
1213 /* Must be called with dev->lock held and irqs disabled */
1214 static void gr_udc_usbreset(struct gr_udc *dev, u32 status)
1215 {
1216         gr_set_address(dev, 0);
1217         gr_set_ep0state(dev, GR_EP0_SETUP);
1218         usb_gadget_set_state(&dev->gadget, USB_STATE_DEFAULT);
1219         dev->gadget.speed = GR_SPEED(status);
1220
1221         gr_ep_nuke(&dev->epo[0]);
1222         gr_ep_nuke(&dev->epi[0]);
1223         dev->epo[0].stopped = 0;
1224         dev->epi[0].stopped = 0;
1225         gr_ep0out_requeue(dev);
1226 }
1227
1228 /* ---------------------------------------------------------------------- */
1229 /* Irq handling */
1230
1231 /*
1232  * Handles interrupts from in endpoints. Returns whether something was handled.
1233  *
1234  * Must be called with dev->lock held, irqs disabled and with !ep->stopped.
1235  */
1236 static int gr_handle_in_ep(struct gr_ep *ep)
1237 {
1238         struct gr_request *req;
1239
1240         req = list_first_entry(&ep->queue, struct gr_request, queue);
1241         if (!req->last_desc)
1242                 return 0;
1243
1244         if (READ_ONCE(req->last_desc->ctrl) & GR_DESC_IN_CTRL_EN)
1245                 return 0; /* Not put in hardware buffers yet */
1246
1247         if (gr_read32(&ep->regs->epstat) & (GR_EPSTAT_B1 | GR_EPSTAT_B0))
1248                 return 0; /* Not transmitted yet, still in hardware buffers */
1249
1250         /* Write complete */
1251         gr_dma_advance(ep, 0);
1252
1253         return 1;
1254 }
1255
1256 /*
1257  * Handles interrupts from out endpoints. Returns whether something was handled.
1258  *
1259  * Must be called with dev->lock held, irqs disabled and with !ep->stopped.
1260  */
1261 static int gr_handle_out_ep(struct gr_ep *ep)
1262 {
1263         u32 ep_dmactrl;
1264         u32 ctrl;
1265         u16 len;
1266         struct gr_request *req;
1267         struct gr_udc *dev = ep->dev;
1268
1269         req = list_first_entry(&ep->queue, struct gr_request, queue);
1270         if (!req->curr_desc)
1271                 return 0;
1272
1273         ctrl = READ_ONCE(req->curr_desc->ctrl);
1274         if (ctrl & GR_DESC_OUT_CTRL_EN)
1275                 return 0; /* Not received yet */
1276
1277         /* Read complete */
1278         len = ctrl & GR_DESC_OUT_CTRL_LEN_MASK;
1279         req->req.actual += len;
1280         if (ctrl & GR_DESC_OUT_CTRL_SE)
1281                 req->setup = 1;
1282
1283         if (len < ep->ep.maxpacket || req->req.actual >= req->req.length) {
1284                 /* Short packet or >= expected size - we are done */
1285
1286                 if ((ep == &dev->epo[0]) && (dev->ep0state == GR_EP0_OSTATUS)) {
1287                         /*
1288                          * Send a status stage ZLP to ack the DATA stage in the
1289                          * OUT direction. This needs to be done before
1290                          * gr_dma_advance as that can lead to a call to
1291                          * ep0_setup that can change dev->ep0state.
1292                          */
1293                         gr_ep0_respond_empty(dev);
1294                         gr_set_ep0state(dev, GR_EP0_SETUP);
1295                 }
1296
1297                 gr_dma_advance(ep, 0);
1298         } else {
1299                 /* Not done yet. Enable the next descriptor to receive more. */
1300                 req->curr_desc = req->curr_desc->next_desc;
1301                 req->curr_desc->ctrl |= GR_DESC_OUT_CTRL_EN;
1302
1303                 ep_dmactrl = gr_read32(&ep->regs->dmactrl);
1304                 gr_write32(&ep->regs->dmactrl, ep_dmactrl | GR_DMACTRL_DA);
1305         }
1306
1307         return 1;
1308 }
1309
1310 /*
1311  * Handle state changes. Returns whether something was handled.
1312  *
1313  * Must be called with dev->lock held and irqs disabled.
1314  */
1315 static int gr_handle_state_changes(struct gr_udc *dev)
1316 {
1317         u32 status = gr_read32(&dev->regs->status);
1318         int handled = 0;
1319         int powstate = !(dev->gadget.state == USB_STATE_NOTATTACHED ||
1320                          dev->gadget.state == USB_STATE_ATTACHED);
1321
1322         /* VBUS valid detected */
1323         if (!powstate && (status & GR_STATUS_VB)) {
1324                 dev_dbg(dev->dev, "STATUS: vbus valid detected\n");
1325                 gr_vbus_connected(dev, status);
1326                 handled = 1;
1327         }
1328
1329         /* Disconnect */
1330         if (powstate && !(status & GR_STATUS_VB)) {
1331                 dev_dbg(dev->dev, "STATUS: vbus invalid detected\n");
1332                 gr_vbus_disconnected(dev);
1333                 handled = 1;
1334         }
1335
1336         /* USB reset detected */
1337         if (status & GR_STATUS_UR) {
1338                 dev_dbg(dev->dev, "STATUS: USB reset - speed is %s\n",
1339                         GR_SPEED_STR(status));
1340                 gr_write32(&dev->regs->status, GR_STATUS_UR);
1341                 gr_udc_usbreset(dev, status);
1342                 handled = 1;
1343         }
1344
1345         /* Speed change */
1346         if (dev->gadget.speed != GR_SPEED(status)) {
1347                 dev_dbg(dev->dev, "STATUS: USB Speed change to %s\n",
1348                         GR_SPEED_STR(status));
1349                 dev->gadget.speed = GR_SPEED(status);
1350                 handled = 1;
1351         }
1352
1353         /* Going into suspend */
1354         if ((dev->ep0state != GR_EP0_SUSPEND) && !(status & GR_STATUS_SU)) {
1355                 dev_dbg(dev->dev, "STATUS: USB suspend\n");
1356                 gr_set_ep0state(dev, GR_EP0_SUSPEND);
1357                 dev->suspended_from = dev->gadget.state;
1358                 usb_gadget_set_state(&dev->gadget, USB_STATE_SUSPENDED);
1359
1360                 if ((dev->gadget.speed != USB_SPEED_UNKNOWN) &&
1361                     dev->driver && dev->driver->suspend) {
1362                         spin_unlock(&dev->lock);
1363
1364                         dev->driver->suspend(&dev->gadget);
1365
1366                         spin_lock(&dev->lock);
1367                 }
1368                 handled = 1;
1369         }
1370
1371         /* Coming out of suspend */
1372         if ((dev->ep0state == GR_EP0_SUSPEND) && (status & GR_STATUS_SU)) {
1373                 dev_dbg(dev->dev, "STATUS: USB resume\n");
1374                 if (dev->suspended_from == USB_STATE_POWERED)
1375                         gr_set_ep0state(dev, GR_EP0_DISCONNECT);
1376                 else
1377                         gr_set_ep0state(dev, GR_EP0_SETUP);
1378                 usb_gadget_set_state(&dev->gadget, dev->suspended_from);
1379
1380                 if ((dev->gadget.speed != USB_SPEED_UNKNOWN) &&
1381                     dev->driver && dev->driver->resume) {
1382                         spin_unlock(&dev->lock);
1383
1384                         dev->driver->resume(&dev->gadget);
1385
1386                         spin_lock(&dev->lock);
1387                 }
1388                 handled = 1;
1389         }
1390
1391         return handled;
1392 }
1393
1394 /* Non-interrupt context irq handler */
1395 static irqreturn_t gr_irq_handler(int irq, void *_dev)
1396 {
1397         struct gr_udc *dev = _dev;
1398         struct gr_ep *ep;
1399         int handled = 0;
1400         int i;
1401         unsigned long flags;
1402
1403         spin_lock_irqsave(&dev->lock, flags);
1404
1405         if (!dev->irq_enabled)
1406                 goto out;
1407
1408         /*
1409          * Check IN ep interrupts. We check these before the OUT eps because
1410          * some gadgets reuse the request that might already be currently
1411          * outstanding and needs to be completed (mainly setup requests).
1412          */
1413         for (i = 0; i < dev->nepi; i++) {
1414                 ep = &dev->epi[i];
1415                 if (!ep->stopped && !ep->callback && !list_empty(&ep->queue))
1416                         handled = gr_handle_in_ep(ep) || handled;
1417         }
1418
1419         /* Check OUT ep interrupts */
1420         for (i = 0; i < dev->nepo; i++) {
1421                 ep = &dev->epo[i];
1422                 if (!ep->stopped && !ep->callback && !list_empty(&ep->queue))
1423                         handled = gr_handle_out_ep(ep) || handled;
1424         }
1425
1426         /* Check status interrupts */
1427         handled = gr_handle_state_changes(dev) || handled;
1428
1429         /*
1430          * Check AMBA DMA errors. Only check if we didn't find anything else to
1431          * handle because this shouldn't happen if we did everything right.
1432          */
1433         if (!handled) {
1434                 list_for_each_entry(ep, &dev->ep_list, ep_list) {
1435                         if (gr_read32(&ep->regs->dmactrl) & GR_DMACTRL_AE) {
1436                                 dev_err(dev->dev,
1437                                         "AMBA Error occurred for %s\n",
1438                                         ep->ep.name);
1439                                 handled = 1;
1440                         }
1441                 }
1442         }
1443
1444 out:
1445         spin_unlock_irqrestore(&dev->lock, flags);
1446
1447         return handled ? IRQ_HANDLED : IRQ_NONE;
1448 }
1449
1450 /* Interrupt context irq handler */
1451 static irqreturn_t gr_irq(int irq, void *_dev)
1452 {
1453         struct gr_udc *dev = _dev;
1454
1455         if (!dev->irq_enabled)
1456                 return IRQ_NONE;
1457
1458         return IRQ_WAKE_THREAD;
1459 }
1460
1461 /* ---------------------------------------------------------------------- */
1462 /* USB ep ops */
1463
1464 /* Enable endpoint. Not for ep0in and ep0out that are handled separately. */
1465 static int gr_ep_enable(struct usb_ep *_ep,
1466                         const struct usb_endpoint_descriptor *desc)
1467 {
1468         struct gr_udc *dev;
1469         struct gr_ep *ep;
1470         u8 mode;
1471         u8 nt;
1472         u16 max;
1473         u16 buffer_size = 0;
1474         u32 epctrl;
1475
1476         ep = container_of(_ep, struct gr_ep, ep);
1477         if (!_ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT)
1478                 return -EINVAL;
1479
1480         dev = ep->dev;
1481
1482         /* 'ep0' IN and OUT are reserved */
1483         if (ep == &dev->epo[0] || ep == &dev->epi[0])
1484                 return -EINVAL;
1485
1486         if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)
1487                 return -ESHUTDOWN;
1488
1489         /* Make sure we are clear for enabling */
1490         epctrl = gr_read32(&ep->regs->epctrl);
1491         if (epctrl & GR_EPCTRL_EV)
1492                 return -EBUSY;
1493
1494         /* Check that directions match */
1495         if (!ep->is_in != !usb_endpoint_dir_in(desc))
1496                 return -EINVAL;
1497
1498         /* Check ep num */
1499         if ((!ep->is_in && ep->num >= dev->nepo) ||
1500             (ep->is_in && ep->num >= dev->nepi))
1501                 return -EINVAL;
1502
1503         if (usb_endpoint_xfer_control(desc)) {
1504                 mode = 0;
1505         } else if (usb_endpoint_xfer_isoc(desc)) {
1506                 mode = 1;
1507         } else if (usb_endpoint_xfer_bulk(desc)) {
1508                 mode = 2;
1509         } else if (usb_endpoint_xfer_int(desc)) {
1510                 mode = 3;
1511         } else {
1512                 dev_err(dev->dev, "Unknown transfer type for %s\n",
1513                         ep->ep.name);
1514                 return -EINVAL;
1515         }
1516
1517         /*
1518          * Bits 10-0 set the max payload. 12-11 set the number of
1519          * additional transactions.
1520          */
1521         max = usb_endpoint_maxp(desc);
1522         nt = usb_endpoint_maxp_mult(desc) - 1;
1523         buffer_size = GR_BUFFER_SIZE(epctrl);
1524         if (nt && (mode == 0 || mode == 2)) {
1525                 dev_err(dev->dev,
1526                         "%s mode: multiple trans./microframe not valid\n",
1527                         (mode == 2 ? "Bulk" : "Control"));
1528                 return -EINVAL;
1529         } else if (nt == 0x3) {
1530                 dev_err(dev->dev,
1531                         "Invalid value 0x3 for additional trans./microframe\n");
1532                 return -EINVAL;
1533         } else if ((nt + 1) * max > buffer_size) {
1534                 dev_err(dev->dev, "Hw buffer size %d < max payload %d * %d\n",
1535                         buffer_size, (nt + 1), max);
1536                 return -EINVAL;
1537         } else if (max == 0) {
1538                 dev_err(dev->dev, "Max payload cannot be set to 0\n");
1539                 return -EINVAL;
1540         } else if (max > ep->ep.maxpacket_limit) {
1541                 dev_err(dev->dev, "Requested max payload %d > limit %d\n",
1542                         max, ep->ep.maxpacket_limit);
1543                 return -EINVAL;
1544         }
1545
1546         spin_lock(&ep->dev->lock);
1547
1548         if (!ep->stopped) {
1549                 spin_unlock(&ep->dev->lock);
1550                 return -EBUSY;
1551         }
1552
1553         ep->stopped = 0;
1554         ep->wedged = 0;
1555         ep->ep.desc = desc;
1556         ep->ep.maxpacket = max;
1557         ep->dma_start = 0;
1558
1559
1560         if (nt) {
1561                 /*
1562                  * Maximum possible size of all payloads in one microframe
1563                  * regardless of direction when using high-bandwidth mode.
1564                  */
1565                 ep->bytes_per_buffer = (nt + 1) * max;
1566         } else if (ep->is_in) {
1567                 /*
1568                  * The biggest multiple of maximum packet size that fits into
1569                  * the buffer. The hardware will split up into many packets in
1570                  * the IN direction.
1571                  */
1572                 ep->bytes_per_buffer = (buffer_size / max) * max;
1573         } else {
1574                 /*
1575                  * Only single packets will be placed the buffers in the OUT
1576                  * direction.
1577                  */
1578                 ep->bytes_per_buffer = max;
1579         }
1580
1581         epctrl = (max << GR_EPCTRL_MAXPL_POS)
1582                 | (nt << GR_EPCTRL_NT_POS)
1583                 | (mode << GR_EPCTRL_TT_POS)
1584                 | GR_EPCTRL_EV;
1585         if (ep->is_in)
1586                 epctrl |= GR_EPCTRL_PI;
1587         gr_write32(&ep->regs->epctrl, epctrl);
1588
1589         gr_write32(&ep->regs->dmactrl, GR_DMACTRL_IE | GR_DMACTRL_AI);
1590
1591         spin_unlock(&ep->dev->lock);
1592
1593         dev_dbg(ep->dev->dev, "EP: %s enabled - %s with %d bytes/buffer\n",
1594                 ep->ep.name, gr_modestring[mode], ep->bytes_per_buffer);
1595         return 0;
1596 }
1597
1598 /* Disable endpoint. Not for ep0in and ep0out that are handled separately. */
1599 static int gr_ep_disable(struct usb_ep *_ep)
1600 {
1601         struct gr_ep *ep;
1602         struct gr_udc *dev;
1603         unsigned long flags;
1604
1605         ep = container_of(_ep, struct gr_ep, ep);
1606         if (!_ep || !ep->ep.desc)
1607                 return -ENODEV;
1608
1609         dev = ep->dev;
1610
1611         /* 'ep0' IN and OUT are reserved */
1612         if (ep == &dev->epo[0] || ep == &dev->epi[0])
1613                 return -EINVAL;
1614
1615         if (dev->ep0state == GR_EP0_SUSPEND)
1616                 return -EBUSY;
1617
1618         dev_dbg(ep->dev->dev, "EP: disable %s\n", ep->ep.name);
1619
1620         spin_lock_irqsave(&dev->lock, flags);
1621
1622         gr_ep_nuke(ep);
1623         gr_ep_reset(ep);
1624         ep->ep.desc = NULL;
1625
1626         spin_unlock_irqrestore(&dev->lock, flags);
1627
1628         return 0;
1629 }
1630
1631 /*
1632  * Frees a request, but not any DMA buffers associated with it
1633  * (gr_finish_request should already have taken care of that).
1634  */
1635 static void gr_free_request(struct usb_ep *_ep, struct usb_request *_req)
1636 {
1637         struct gr_request *req;
1638
1639         if (!_ep || !_req)
1640                 return;
1641         req = container_of(_req, struct gr_request, req);
1642
1643         /* Leads to memory leak */
1644         WARN(!list_empty(&req->queue),
1645              "request not dequeued properly before freeing\n");
1646
1647         kfree(req);
1648 }
1649
1650 /* Queue a request from the gadget */
1651 static int gr_queue_ext(struct usb_ep *_ep, struct usb_request *_req,
1652                         gfp_t gfp_flags)
1653 {
1654         struct gr_ep *ep;
1655         struct gr_request *req;
1656         struct gr_udc *dev;
1657         int ret;
1658
1659         if (unlikely(!_ep || !_req))
1660                 return -EINVAL;
1661
1662         ep = container_of(_ep, struct gr_ep, ep);
1663         req = container_of(_req, struct gr_request, req);
1664         dev = ep->dev;
1665
1666         spin_lock(&ep->dev->lock);
1667
1668         /*
1669          * The ep0 pointer in the gadget struct is used both for ep0in and
1670          * ep0out. In a data stage in the out direction ep0out needs to be used
1671          * instead of the default ep0in. Completion functions might use
1672          * driver_data, so that needs to be copied as well.
1673          */
1674         if ((ep == &dev->epi[0]) && (dev->ep0state == GR_EP0_ODATA)) {
1675                 ep = &dev->epo[0];
1676                 ep->ep.driver_data = dev->epi[0].ep.driver_data;
1677         }
1678
1679         if (ep->is_in)
1680                 gr_dbgprint_request("EXTERN", ep, req);
1681
1682         ret = gr_queue(ep, req, GFP_ATOMIC);
1683
1684         spin_unlock(&ep->dev->lock);
1685
1686         return ret;
1687 }
1688
1689 /* Dequeue JUST ONE request */
1690 static int gr_dequeue(struct usb_ep *_ep, struct usb_request *_req)
1691 {
1692         struct gr_request *req = NULL, *iter;
1693         struct gr_ep *ep;
1694         struct gr_udc *dev;
1695         int ret = 0;
1696         unsigned long flags;
1697
1698         ep = container_of(_ep, struct gr_ep, ep);
1699         if (!_ep || !_req || (!ep->ep.desc && ep->num != 0))
1700                 return -EINVAL;
1701         dev = ep->dev;
1702         if (!dev->driver)
1703                 return -ESHUTDOWN;
1704
1705         /* We can't touch (DMA) registers when suspended */
1706         if (dev->ep0state == GR_EP0_SUSPEND)
1707                 return -EBUSY;
1708
1709         spin_lock_irqsave(&dev->lock, flags);
1710
1711         /* Make sure it's actually queued on this endpoint */
1712         list_for_each_entry(iter, &ep->queue, queue) {
1713                 if (&iter->req != _req)
1714                         continue;
1715                 req = iter;
1716                 break;
1717         }
1718         if (!req) {
1719                 ret = -EINVAL;
1720                 goto out;
1721         }
1722
1723         if (list_first_entry(&ep->queue, struct gr_request, queue) == req) {
1724                 /* This request is currently being processed */
1725                 gr_abort_dma(ep);
1726                 if (ep->stopped)
1727                         gr_finish_request(ep, req, -ECONNRESET);
1728                 else
1729                         gr_dma_advance(ep, -ECONNRESET);
1730         } else if (!list_empty(&req->queue)) {
1731                 /* Not being processed - gr_finish_request dequeues it */
1732                 gr_finish_request(ep, req, -ECONNRESET);
1733         } else {
1734                 ret = -EOPNOTSUPP;
1735         }
1736
1737 out:
1738         spin_unlock_irqrestore(&dev->lock, flags);
1739
1740         return ret;
1741 }
1742
1743 /* Helper for gr_set_halt and gr_set_wedge */
1744 static int gr_set_halt_wedge(struct usb_ep *_ep, int halt, int wedge)
1745 {
1746         int ret;
1747         struct gr_ep *ep;
1748
1749         if (!_ep)
1750                 return -ENODEV;
1751         ep = container_of(_ep, struct gr_ep, ep);
1752
1753         spin_lock(&ep->dev->lock);
1754
1755         /* Halting an IN endpoint should fail if queue is not empty */
1756         if (halt && ep->is_in && !list_empty(&ep->queue)) {
1757                 ret = -EAGAIN;
1758                 goto out;
1759         }
1760
1761         ret = gr_ep_halt_wedge(ep, halt, wedge, 0);
1762
1763 out:
1764         spin_unlock(&ep->dev->lock);
1765
1766         return ret;
1767 }
1768
1769 /* Halt endpoint */
1770 static int gr_set_halt(struct usb_ep *_ep, int halt)
1771 {
1772         return gr_set_halt_wedge(_ep, halt, 0);
1773 }
1774
1775 /* Halt and wedge endpoint */
1776 static int gr_set_wedge(struct usb_ep *_ep)
1777 {
1778         return gr_set_halt_wedge(_ep, 1, 1);
1779 }
1780
1781 /*
1782  * Return the total number of bytes currently stored in the internal buffers of
1783  * the endpoint.
1784  */
1785 static int gr_fifo_status(struct usb_ep *_ep)
1786 {
1787         struct gr_ep *ep;
1788         u32 epstat;
1789         u32 bytes = 0;
1790
1791         if (!_ep)
1792                 return -ENODEV;
1793         ep = container_of(_ep, struct gr_ep, ep);
1794
1795         epstat = gr_read32(&ep->regs->epstat);
1796
1797         if (epstat & GR_EPSTAT_B0)
1798                 bytes += (epstat & GR_EPSTAT_B0CNT_MASK) >> GR_EPSTAT_B0CNT_POS;
1799         if (epstat & GR_EPSTAT_B1)
1800                 bytes += (epstat & GR_EPSTAT_B1CNT_MASK) >> GR_EPSTAT_B1CNT_POS;
1801
1802         return bytes;
1803 }
1804
1805
1806 /* Empty data from internal buffers of an endpoint. */
1807 static void gr_fifo_flush(struct usb_ep *_ep)
1808 {
1809         struct gr_ep *ep;
1810         u32 epctrl;
1811
1812         if (!_ep)
1813                 return;
1814         ep = container_of(_ep, struct gr_ep, ep);
1815         dev_vdbg(ep->dev->dev, "EP: flush fifo %s\n", ep->ep.name);
1816
1817         spin_lock(&ep->dev->lock);
1818
1819         epctrl = gr_read32(&ep->regs->epctrl);
1820         epctrl |= GR_EPCTRL_CB;
1821         gr_write32(&ep->regs->epctrl, epctrl);
1822
1823         spin_unlock(&ep->dev->lock);
1824 }
1825
1826 static const struct usb_ep_ops gr_ep_ops = {
1827         .enable         = gr_ep_enable,
1828         .disable        = gr_ep_disable,
1829
1830         .alloc_request  = gr_alloc_request,
1831         .free_request   = gr_free_request,
1832
1833         .queue          = gr_queue_ext,
1834         .dequeue        = gr_dequeue,
1835
1836         .set_halt       = gr_set_halt,
1837         .set_wedge      = gr_set_wedge,
1838         .fifo_status    = gr_fifo_status,
1839         .fifo_flush     = gr_fifo_flush,
1840 };
1841
1842 /* ---------------------------------------------------------------------- */
1843 /* USB Gadget ops */
1844
1845 static int gr_get_frame(struct usb_gadget *_gadget)
1846 {
1847         struct gr_udc *dev;
1848
1849         if (!_gadget)
1850                 return -ENODEV;
1851         dev = container_of(_gadget, struct gr_udc, gadget);
1852         return gr_read32(&dev->regs->status) & GR_STATUS_FN_MASK;
1853 }
1854
1855 static int gr_wakeup(struct usb_gadget *_gadget)
1856 {
1857         struct gr_udc *dev;
1858
1859         if (!_gadget)
1860                 return -ENODEV;
1861         dev = container_of(_gadget, struct gr_udc, gadget);
1862
1863         /* Remote wakeup feature not enabled by host*/
1864         if (!dev->remote_wakeup)
1865                 return -EINVAL;
1866
1867         spin_lock(&dev->lock);
1868
1869         gr_write32(&dev->regs->control,
1870                    gr_read32(&dev->regs->control) | GR_CONTROL_RW);
1871
1872         spin_unlock(&dev->lock);
1873
1874         return 0;
1875 }
1876
1877 static int gr_pullup(struct usb_gadget *_gadget, int is_on)
1878 {
1879         struct gr_udc *dev;
1880         u32 control;
1881
1882         if (!_gadget)
1883                 return -ENODEV;
1884         dev = container_of(_gadget, struct gr_udc, gadget);
1885
1886         spin_lock(&dev->lock);
1887
1888         control = gr_read32(&dev->regs->control);
1889         if (is_on)
1890                 control |= GR_CONTROL_EP;
1891         else
1892                 control &= ~GR_CONTROL_EP;
1893         gr_write32(&dev->regs->control, control);
1894
1895         spin_unlock(&dev->lock);
1896
1897         return 0;
1898 }
1899
1900 static int gr_udc_start(struct usb_gadget *gadget,
1901                         struct usb_gadget_driver *driver)
1902 {
1903         struct gr_udc *dev = to_gr_udc(gadget);
1904
1905         spin_lock(&dev->lock);
1906
1907         /* Hook up the driver */
1908         dev->driver = driver;
1909
1910         /* Get ready for host detection */
1911         gr_enable_vbus_detect(dev);
1912
1913         spin_unlock(&dev->lock);
1914
1915         return 0;
1916 }
1917
1918 static int gr_udc_stop(struct usb_gadget *gadget)
1919 {
1920         struct gr_udc *dev = to_gr_udc(gadget);
1921         unsigned long flags;
1922
1923         spin_lock_irqsave(&dev->lock, flags);
1924
1925         dev->driver = NULL;
1926         gr_stop_activity(dev);
1927
1928         spin_unlock_irqrestore(&dev->lock, flags);
1929
1930         return 0;
1931 }
1932
1933 static const struct usb_gadget_ops gr_ops = {
1934         .get_frame      = gr_get_frame,
1935         .wakeup         = gr_wakeup,
1936         .pullup         = gr_pullup,
1937         .udc_start      = gr_udc_start,
1938         .udc_stop       = gr_udc_stop,
1939         /* Other operations not supported */
1940 };
1941
1942 /* ---------------------------------------------------------------------- */
1943 /* Module probe, removal and of-matching */
1944
1945 static const char * const onames[] = {
1946         "ep0out", "ep1out", "ep2out", "ep3out", "ep4out", "ep5out",
1947         "ep6out", "ep7out", "ep8out", "ep9out", "ep10out", "ep11out",
1948         "ep12out", "ep13out", "ep14out", "ep15out"
1949 };
1950
1951 static const char * const inames[] = {
1952         "ep0in", "ep1in", "ep2in", "ep3in", "ep4in", "ep5in",
1953         "ep6in", "ep7in", "ep8in", "ep9in", "ep10in", "ep11in",
1954         "ep12in", "ep13in", "ep14in", "ep15in"
1955 };
1956
1957 /* Must be called with dev->lock held */
1958 static int gr_ep_init(struct gr_udc *dev, int num, int is_in, u32 maxplimit)
1959 {
1960         struct gr_ep *ep;
1961         struct gr_request *req;
1962         struct usb_request *_req;
1963         void *buf;
1964
1965         if (is_in) {
1966                 ep = &dev->epi[num];
1967                 ep->ep.name = inames[num];
1968                 ep->regs = &dev->regs->epi[num];
1969         } else {
1970                 ep = &dev->epo[num];
1971                 ep->ep.name = onames[num];
1972                 ep->regs = &dev->regs->epo[num];
1973         }
1974
1975         gr_ep_reset(ep);
1976         ep->num = num;
1977         ep->is_in = is_in;
1978         ep->dev = dev;
1979         ep->ep.ops = &gr_ep_ops;
1980         INIT_LIST_HEAD(&ep->queue);
1981
1982         if (num == 0) {
1983                 _req = gr_alloc_request(&ep->ep, GFP_ATOMIC);
1984                 if (!_req)
1985                         return -ENOMEM;
1986
1987                 buf = devm_kzalloc(dev->dev, PAGE_SIZE, GFP_DMA | GFP_ATOMIC);
1988                 if (!buf) {
1989                         gr_free_request(&ep->ep, _req);
1990                         return -ENOMEM;
1991                 }
1992
1993                 req = container_of(_req, struct gr_request, req);
1994                 req->req.buf = buf;
1995                 req->req.length = MAX_CTRL_PL_SIZE;
1996
1997                 if (is_in)
1998                         dev->ep0reqi = req; /* Complete gets set as used */
1999                 else
2000                         dev->ep0reqo = req; /* Completion treated separately */
2001
2002                 usb_ep_set_maxpacket_limit(&ep->ep, MAX_CTRL_PL_SIZE);
2003                 ep->bytes_per_buffer = MAX_CTRL_PL_SIZE;
2004
2005                 ep->ep.caps.type_control = true;
2006         } else {
2007                 usb_ep_set_maxpacket_limit(&ep->ep, (u16)maxplimit);
2008                 list_add_tail(&ep->ep.ep_list, &dev->gadget.ep_list);
2009
2010                 ep->ep.caps.type_iso = true;
2011                 ep->ep.caps.type_bulk = true;
2012                 ep->ep.caps.type_int = true;
2013         }
2014         list_add_tail(&ep->ep_list, &dev->ep_list);
2015
2016         if (is_in)
2017                 ep->ep.caps.dir_in = true;
2018         else
2019                 ep->ep.caps.dir_out = true;
2020
2021         ep->tailbuf = dma_alloc_coherent(dev->dev, ep->ep.maxpacket_limit,
2022                                          &ep->tailbuf_paddr, GFP_ATOMIC);
2023         if (!ep->tailbuf)
2024                 return -ENOMEM;
2025
2026         return 0;
2027 }
2028
2029 /* Must be called with dev->lock held */
2030 static int gr_udc_init(struct gr_udc *dev)
2031 {
2032         struct device_node *np = dev->dev->of_node;
2033         u32 epctrl_val;
2034         u32 dmactrl_val;
2035         int i;
2036         int ret = 0;
2037         u32 bufsize;
2038
2039         gr_set_address(dev, 0);
2040
2041         INIT_LIST_HEAD(&dev->gadget.ep_list);
2042         dev->gadget.speed = USB_SPEED_UNKNOWN;
2043         dev->gadget.ep0 = &dev->epi[0].ep;
2044
2045         INIT_LIST_HEAD(&dev->ep_list);
2046         gr_set_ep0state(dev, GR_EP0_DISCONNECT);
2047
2048         for (i = 0; i < dev->nepo; i++) {
2049                 if (of_property_read_u32_index(np, "epobufsizes", i, &bufsize))
2050                         bufsize = 1024;
2051                 ret = gr_ep_init(dev, i, 0, bufsize);
2052                 if (ret)
2053                         return ret;
2054         }
2055
2056         for (i = 0; i < dev->nepi; i++) {
2057                 if (of_property_read_u32_index(np, "epibufsizes", i, &bufsize))
2058                         bufsize = 1024;
2059                 ret = gr_ep_init(dev, i, 1, bufsize);
2060                 if (ret)
2061                         return ret;
2062         }
2063
2064         /* Must be disabled by default */
2065         dev->remote_wakeup = 0;
2066
2067         /* Enable ep0out and ep0in */
2068         epctrl_val = (MAX_CTRL_PL_SIZE << GR_EPCTRL_MAXPL_POS) | GR_EPCTRL_EV;
2069         dmactrl_val = GR_DMACTRL_IE | GR_DMACTRL_AI;
2070         gr_write32(&dev->epo[0].regs->epctrl, epctrl_val);
2071         gr_write32(&dev->epi[0].regs->epctrl, epctrl_val | GR_EPCTRL_PI);
2072         gr_write32(&dev->epo[0].regs->dmactrl, dmactrl_val);
2073         gr_write32(&dev->epi[0].regs->dmactrl, dmactrl_val);
2074
2075         return 0;
2076 }
2077
2078 static void gr_ep_remove(struct gr_udc *dev, int num, int is_in)
2079 {
2080         struct gr_ep *ep;
2081
2082         if (is_in)
2083                 ep = &dev->epi[num];
2084         else
2085                 ep = &dev->epo[num];
2086
2087         if (ep->tailbuf)
2088                 dma_free_coherent(dev->dev, ep->ep.maxpacket_limit,
2089                                   ep->tailbuf, ep->tailbuf_paddr);
2090 }
2091
2092 static void gr_remove(struct platform_device *pdev)
2093 {
2094         struct gr_udc *dev = platform_get_drvdata(pdev);
2095         int i;
2096
2097         if (dev->added)
2098                 usb_del_gadget_udc(&dev->gadget); /* Shuts everything down */
2099         if (dev->driver) {
2100                 dev_err(&pdev->dev,
2101                         "Driver still in use but removing anyhow\n");
2102                 return;
2103         }
2104
2105         gr_dfs_delete(dev);
2106         dma_pool_destroy(dev->desc_pool);
2107         platform_set_drvdata(pdev, NULL);
2108
2109         gr_free_request(&dev->epi[0].ep, &dev->ep0reqi->req);
2110         gr_free_request(&dev->epo[0].ep, &dev->ep0reqo->req);
2111
2112         for (i = 0; i < dev->nepo; i++)
2113                 gr_ep_remove(dev, i, 0);
2114         for (i = 0; i < dev->nepi; i++)
2115                 gr_ep_remove(dev, i, 1);
2116 }
2117 static int gr_request_irq(struct gr_udc *dev, int irq)
2118 {
2119         return devm_request_threaded_irq(dev->dev, irq, gr_irq, gr_irq_handler,
2120                                          IRQF_SHARED, driver_name, dev);
2121 }
2122
2123 static int gr_probe(struct platform_device *pdev)
2124 {
2125         struct gr_udc *dev;
2126         struct gr_regs __iomem *regs;
2127         int retval;
2128         u32 status;
2129
2130         dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
2131         if (!dev)
2132                 return -ENOMEM;
2133         dev->dev = &pdev->dev;
2134
2135         regs = devm_platform_ioremap_resource(pdev, 0);
2136         if (IS_ERR(regs))
2137                 return PTR_ERR(regs);
2138
2139         dev->irq = platform_get_irq(pdev, 0);
2140         if (dev->irq < 0)
2141                 return dev->irq;
2142
2143         /* Some core configurations has separate irqs for IN and OUT events */
2144         dev->irqi = platform_get_irq(pdev, 1);
2145         if (dev->irqi > 0) {
2146                 dev->irqo = platform_get_irq(pdev, 2);
2147                 if (dev->irqo < 0)
2148                         return dev->irqo;
2149         } else {
2150                 dev->irqi = 0;
2151         }
2152
2153         dev->gadget.name = driver_name;
2154         dev->gadget.max_speed = USB_SPEED_HIGH;
2155         dev->gadget.ops = &gr_ops;
2156
2157         spin_lock_init(&dev->lock);
2158         dev->regs = regs;
2159
2160         platform_set_drvdata(pdev, dev);
2161
2162         /* Determine number of endpoints and data interface mode */
2163         status = gr_read32(&dev->regs->status);
2164         dev->nepi = ((status & GR_STATUS_NEPI_MASK) >> GR_STATUS_NEPI_POS) + 1;
2165         dev->nepo = ((status & GR_STATUS_NEPO_MASK) >> GR_STATUS_NEPO_POS) + 1;
2166
2167         if (!(status & GR_STATUS_DM)) {
2168                 dev_err(dev->dev, "Slave mode cores are not supported\n");
2169                 return -ENODEV;
2170         }
2171
2172         /* --- Effects of the following calls might need explicit cleanup --- */
2173
2174         /* Create DMA pool for descriptors */
2175         dev->desc_pool = dma_pool_create("desc_pool", dev->dev,
2176                                          sizeof(struct gr_dma_desc), 4, 0);
2177         if (!dev->desc_pool) {
2178                 dev_err(dev->dev, "Could not allocate DMA pool");
2179                 return -ENOMEM;
2180         }
2181
2182         /* Inside lock so that no gadget can use this udc until probe is done */
2183         retval = usb_add_gadget_udc(dev->dev, &dev->gadget);
2184         if (retval) {
2185                 dev_err(dev->dev, "Could not add gadget udc");
2186                 goto out;
2187         }
2188         dev->added = 1;
2189
2190         spin_lock(&dev->lock);
2191
2192         retval = gr_udc_init(dev);
2193         if (retval) {
2194                 spin_unlock(&dev->lock);
2195                 goto out;
2196         }
2197
2198         /* Clear all interrupt enables that might be left on since last boot */
2199         gr_disable_interrupts_and_pullup(dev);
2200
2201         spin_unlock(&dev->lock);
2202
2203         gr_dfs_create(dev);
2204
2205         retval = gr_request_irq(dev, dev->irq);
2206         if (retval) {
2207                 dev_err(dev->dev, "Failed to request irq %d\n", dev->irq);
2208                 goto out;
2209         }
2210
2211         if (dev->irqi) {
2212                 retval = gr_request_irq(dev, dev->irqi);
2213                 if (retval) {
2214                         dev_err(dev->dev, "Failed to request irqi %d\n",
2215                                 dev->irqi);
2216                         goto out;
2217                 }
2218                 retval = gr_request_irq(dev, dev->irqo);
2219                 if (retval) {
2220                         dev_err(dev->dev, "Failed to request irqo %d\n",
2221                                 dev->irqo);
2222                         goto out;
2223                 }
2224         }
2225
2226         if (dev->irqi)
2227                 dev_info(dev->dev, "regs: %p, irqs %d, %d, %d\n", dev->regs,
2228                          dev->irq, dev->irqi, dev->irqo);
2229         else
2230                 dev_info(dev->dev, "regs: %p, irq %d\n", dev->regs, dev->irq);
2231
2232 out:
2233         if (retval)
2234                 gr_remove(pdev);
2235
2236         return retval;
2237 }
2238
2239 static const struct of_device_id gr_match[] = {
2240         {.name = "GAISLER_USBDC"},
2241         {.name = "01_021"},
2242         {},
2243 };
2244 MODULE_DEVICE_TABLE(of, gr_match);
2245
2246 static struct platform_driver gr_driver = {
2247         .driver = {
2248                 .name = DRIVER_NAME,
2249                 .of_match_table = gr_match,
2250         },
2251         .probe = gr_probe,
2252         .remove_new = gr_remove,
2253 };
2254 module_platform_driver(gr_driver);
2255
2256 MODULE_AUTHOR("Aeroflex Gaisler AB.");
2257 MODULE_DESCRIPTION(DRIVER_DESC);
2258 MODULE_LICENSE("GPL");