root/drivers/usb/gadget/udc/gr_udc.c

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DEFINITIONS

This source file includes following definitions.
  1. gr_ep0state_string
  2. gr_dbgprint_request
  3. gr_dbgprint_devreq
  4. gr_dbgprint_request
  5. gr_dbgprint_devreq
  6. gr_seq_ep_show
  7. gr_dfs_show
  8. gr_dfs_create
  9. gr_dfs_delete
  10. gr_dfs_create
  11. gr_dfs_delete
  12. gr_alloc_dma_desc
  13. gr_free_dma_desc
  14. gr_free_dma_desc_chain
  15. gr_finish_request
  16. gr_alloc_request
  17. gr_start_dma
  18. gr_dma_advance
  19. gr_abort_dma
  20. gr_add_dma_desc
  21. gr_setup_out_desc_list
  22. gr_setup_in_desc_list
  23. gr_queue
  24. gr_queue_int
  25. gr_ep_nuke
  26. gr_ep_reset
  27. gr_control_stall
  28. gr_ep_halt_wedge
  29. gr_set_ep0state
  30. gr_disable_interrupts_and_pullup
  31. gr_stop_activity
  32. gr_ep0_testmode_complete
  33. gr_ep0_dummy_complete
  34. gr_ep0_respond
  35. gr_ep0_respond_u16
  36. gr_ep0_respond_empty
  37. gr_set_address
  38. gr_device_request
  39. gr_interface_request
  40. gr_endpoint_request
  41. gr_ep0out_requeue
  42. gr_ep0_setup
  43. gr_vbus_connected
  44. gr_enable_vbus_detect
  45. gr_vbus_disconnected
  46. gr_udc_usbreset
  47. gr_handle_in_ep
  48. gr_handle_out_ep
  49. gr_handle_state_changes
  50. gr_irq_handler
  51. gr_irq
  52. gr_ep_enable
  53. gr_ep_disable
  54. gr_free_request
  55. gr_queue_ext
  56. gr_dequeue
  57. gr_set_halt_wedge
  58. gr_set_halt
  59. gr_set_wedge
  60. gr_fifo_status
  61. gr_fifo_flush
  62. gr_get_frame
  63. gr_wakeup
  64. gr_pullup
  65. gr_udc_start
  66. gr_udc_stop
  67. gr_ep_init
  68. gr_udc_init
  69. gr_ep_remove
  70. gr_remove
  71. gr_request_irq
  72. gr_probe

   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  * http://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/slab.h>
  27 #include <linux/spinlock.h>
  28 #include <linux/errno.h>
  29 #include <linux/list.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/device.h>
  32 #include <linux/usb/ch9.h>
  33 #include <linux/usb/gadget.h>
  34 #include <linux/dma-mapping.h>
  35 #include <linux/dmapool.h>
  36 #include <linux/debugfs.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/of_platform.h>
  39 #include <linux/of_irq.h>
  40 #include <linux/of_address.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 static const char driver_desc[] = DRIVER_DESC;
  51 
  52 #define gr_read32(x) (ioread32be((x)))
  53 #define gr_write32(x, v) (iowrite32be((v), (x)))
  54 
  55 /* USB speed and corresponding string calculated from status register value */
  56 #define GR_SPEED(status) \
  57         ((status & GR_STATUS_SP) ? USB_SPEED_FULL : USB_SPEED_HIGH)
  58 #define GR_SPEED_STR(status) usb_speed_string(GR_SPEED(status))
  59 
  60 /* Size of hardware buffer calculated from epctrl register value */
  61 #define GR_BUFFER_SIZE(epctrl)                                        \
  62         ((((epctrl) & GR_EPCTRL_BUFSZ_MASK) >> GR_EPCTRL_BUFSZ_POS) * \
  63          GR_EPCTRL_BUFSZ_SCALER)
  64 
  65 /* ---------------------------------------------------------------------- */
  66 /* Debug printout functionality */
  67 
  68 static const char * const gr_modestring[] = {"control", "iso", "bulk", "int"};
  69 
  70 static const char *gr_ep0state_string(enum gr_ep0state state)
  71 {
  72         static const char *const names[] = {
  73                 [GR_EP0_DISCONNECT] = "disconnect",
  74                 [GR_EP0_SETUP] = "setup",
  75                 [GR_EP0_IDATA] = "idata",
  76                 [GR_EP0_ODATA] = "odata",
  77                 [GR_EP0_ISTATUS] = "istatus",
  78                 [GR_EP0_OSTATUS] = "ostatus",
  79                 [GR_EP0_STALL] = "stall",
  80                 [GR_EP0_SUSPEND] = "suspend",
  81         };
  82 
  83         if (state < 0 || state >= ARRAY_SIZE(names))
  84                 return "UNKNOWN";
  85 
  86         return names[state];
  87 }
  88 
  89 #ifdef VERBOSE_DEBUG
  90 
  91 static void gr_dbgprint_request(const char *str, struct gr_ep *ep,
  92                                 struct gr_request *req)
  93 {
  94         int buflen = ep->is_in ? req->req.length : req->req.actual;
  95         int rowlen = 32;
  96         int plen = min(rowlen, buflen);
  97 
  98         dev_dbg(ep->dev->dev, "%s: 0x%p, %d bytes data%s:\n", str, req, buflen,
  99                 (buflen > plen ? " (truncated)" : ""));
 100         print_hex_dump_debug("   ", DUMP_PREFIX_NONE,
 101                              rowlen, 4, req->req.buf, plen, false);
 102 }
 103 
 104 static void gr_dbgprint_devreq(struct gr_udc *dev, u8 type, u8 request,
 105                                u16 value, u16 index, u16 length)
 106 {
 107         dev_vdbg(dev->dev, "REQ: %02x.%02x v%04x i%04x l%04x\n",
 108                  type, request, value, index, length);
 109 }
 110 #else /* !VERBOSE_DEBUG */
 111 
 112 static void gr_dbgprint_request(const char *str, struct gr_ep *ep,
 113                                 struct gr_request *req) {}
 114 
 115 static void gr_dbgprint_devreq(struct gr_udc *dev, u8 type, u8 request,
 116                                u16 value, u16 index, u16 length) {}
 117 
 118 #endif /* VERBOSE_DEBUG */
 119 
 120 /* ---------------------------------------------------------------------- */
 121 /* Debugfs functionality */
 122 
 123 #ifdef CONFIG_USB_GADGET_DEBUG_FS
 124 
 125 static void gr_seq_ep_show(struct seq_file *seq, struct gr_ep *ep)
 126 {
 127         u32 epctrl = gr_read32(&ep->regs->epctrl);
 128         u32 epstat = gr_read32(&ep->regs->epstat);
 129         int mode = (epctrl & GR_EPCTRL_TT_MASK) >> GR_EPCTRL_TT_POS;
 130         struct gr_request *req;
 131 
 132         seq_printf(seq, "%s:\n", ep->ep.name);
 133         seq_printf(seq, "  mode = %s\n", gr_modestring[mode]);
 134         seq_printf(seq, "  halted: %d\n", !!(epctrl & GR_EPCTRL_EH));
 135         seq_printf(seq, "  disabled: %d\n", !!(epctrl & GR_EPCTRL_ED));
 136         seq_printf(seq, "  valid: %d\n", !!(epctrl & GR_EPCTRL_EV));
 137         seq_printf(seq, "  dma_start = %d\n", ep->dma_start);
 138         seq_printf(seq, "  stopped = %d\n", ep->stopped);
 139         seq_printf(seq, "  wedged = %d\n", ep->wedged);
 140         seq_printf(seq, "  callback = %d\n", ep->callback);
 141         seq_printf(seq, "  maxpacket = %d\n", ep->ep.maxpacket);
 142         seq_printf(seq, "  maxpacket_limit = %d\n", ep->ep.maxpacket_limit);
 143         seq_printf(seq, "  bytes_per_buffer = %d\n", ep->bytes_per_buffer);
 144         if (mode == 1 || mode == 3)
 145                 seq_printf(seq, "  nt = %d\n",
 146                            (epctrl & GR_EPCTRL_NT_MASK) >> GR_EPCTRL_NT_POS);
 147 
 148         seq_printf(seq, "  Buffer 0: %s %s%d\n",
 149                    epstat & GR_EPSTAT_B0 ? "valid" : "invalid",
 150                    epstat & GR_EPSTAT_BS ? " " : "selected ",
 151                    (epstat & GR_EPSTAT_B0CNT_MASK) >> GR_EPSTAT_B0CNT_POS);
 152         seq_printf(seq, "  Buffer 1: %s %s%d\n",
 153                    epstat & GR_EPSTAT_B1 ? "valid" : "invalid",
 154                    epstat & GR_EPSTAT_BS ? "selected " : " ",
 155                    (epstat & GR_EPSTAT_B1CNT_MASK) >> GR_EPSTAT_B1CNT_POS);
 156 
 157         if (list_empty(&ep->queue)) {
 158                 seq_puts(seq, "  Queue: empty\n\n");
 159                 return;
 160         }
 161 
 162         seq_puts(seq, "  Queue:\n");
 163         list_for_each_entry(req, &ep->queue, queue) {
 164                 struct gr_dma_desc *desc;
 165                 struct gr_dma_desc *next;
 166 
 167                 seq_printf(seq, "    0x%p: 0x%p %d %d\n", req,
 168                            &req->req.buf, req->req.actual, req->req.length);
 169 
 170                 next = req->first_desc;
 171                 do {
 172                         desc = next;
 173                         next = desc->next_desc;
 174                         seq_printf(seq, "    %c 0x%p (0x%08x): 0x%05x 0x%08x\n",
 175                                    desc == req->curr_desc ? 'c' : ' ',
 176                                    desc, desc->paddr, desc->ctrl, desc->data);
 177                 } while (desc != req->last_desc);
 178         }
 179         seq_puts(seq, "\n");
 180 }
 181 
 182 static int gr_dfs_show(struct seq_file *seq, void *v)
 183 {
 184         struct gr_udc *dev = seq->private;
 185         u32 control = gr_read32(&dev->regs->control);
 186         u32 status = gr_read32(&dev->regs->status);
 187         struct gr_ep *ep;
 188 
 189         seq_printf(seq, "usb state = %s\n",
 190                    usb_state_string(dev->gadget.state));
 191         seq_printf(seq, "address = %d\n",
 192                    (control & GR_CONTROL_UA_MASK) >> GR_CONTROL_UA_POS);
 193         seq_printf(seq, "speed = %s\n", GR_SPEED_STR(status));
 194         seq_printf(seq, "ep0state = %s\n", gr_ep0state_string(dev->ep0state));
 195         seq_printf(seq, "irq_enabled = %d\n", dev->irq_enabled);
 196         seq_printf(seq, "remote_wakeup = %d\n", dev->remote_wakeup);
 197         seq_printf(seq, "test_mode = %d\n", dev->test_mode);
 198         seq_puts(seq, "\n");
 199 
 200         list_for_each_entry(ep, &dev->ep_list, ep_list)
 201                 gr_seq_ep_show(seq, ep);
 202 
 203         return 0;
 204 }
 205 DEFINE_SHOW_ATTRIBUTE(gr_dfs);
 206 
 207 static void gr_dfs_create(struct gr_udc *dev)
 208 {
 209         const char *name = "gr_udc_state";
 210 
 211         dev->dfs_root = debugfs_create_dir(dev_name(dev->dev), NULL);
 212         debugfs_create_file(name, 0444, dev->dfs_root, dev, &gr_dfs_fops);
 213 }
 214 
 215 static void gr_dfs_delete(struct gr_udc *dev)
 216 {
 217         debugfs_remove_recursive(dev->dfs_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 TEST_FORCE_EN */
 916                         test = index >> 8;
 917                         if (test >= TEST_J && test <= 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;
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(req, &ep->queue, queue) {
1713                 if (&req->req == _req)
1714                         break;
1715         }
1716         if (&req->req != _req) {
1717                 ret = -EINVAL;
1718                 goto out;
1719         }
1720 
1721         if (list_first_entry(&ep->queue, struct gr_request, queue) == req) {
1722                 /* This request is currently being processed */
1723                 gr_abort_dma(ep);
1724                 if (ep->stopped)
1725                         gr_finish_request(ep, req, -ECONNRESET);
1726                 else
1727                         gr_dma_advance(ep, -ECONNRESET);
1728         } else if (!list_empty(&req->queue)) {
1729                 /* Not being processed - gr_finish_request dequeues it */
1730                 gr_finish_request(ep, req, -ECONNRESET);
1731         } else {
1732                 ret = -EOPNOTSUPP;
1733         }
1734 
1735 out:
1736         spin_unlock_irqrestore(&dev->lock, flags);
1737 
1738         return ret;
1739 }
1740 
1741 /* Helper for gr_set_halt and gr_set_wedge */
1742 static int gr_set_halt_wedge(struct usb_ep *_ep, int halt, int wedge)
1743 {
1744         int ret;
1745         struct gr_ep *ep;
1746 
1747         if (!_ep)
1748                 return -ENODEV;
1749         ep = container_of(_ep, struct gr_ep, ep);
1750 
1751         spin_lock(&ep->dev->lock);
1752 
1753         /* Halting an IN endpoint should fail if queue is not empty */
1754         if (halt && ep->is_in && !list_empty(&ep->queue)) {
1755                 ret = -EAGAIN;
1756                 goto out;
1757         }
1758 
1759         ret = gr_ep_halt_wedge(ep, halt, wedge, 0);
1760 
1761 out:
1762         spin_unlock(&ep->dev->lock);
1763 
1764         return ret;
1765 }
1766 
1767 /* Halt endpoint */
1768 static int gr_set_halt(struct usb_ep *_ep, int halt)
1769 {
1770         return gr_set_halt_wedge(_ep, halt, 0);
1771 }
1772 
1773 /* Halt and wedge endpoint */
1774 static int gr_set_wedge(struct usb_ep *_ep)
1775 {
1776         return gr_set_halt_wedge(_ep, 1, 1);
1777 }
1778 
1779 /*
1780  * Return the total number of bytes currently stored in the internal buffers of
1781  * the endpoint.
1782  */
1783 static int gr_fifo_status(struct usb_ep *_ep)
1784 {
1785         struct gr_ep *ep;
1786         u32 epstat;
1787         u32 bytes = 0;
1788 
1789         if (!_ep)
1790                 return -ENODEV;
1791         ep = container_of(_ep, struct gr_ep, ep);
1792 
1793         epstat = gr_read32(&ep->regs->epstat);
1794 
1795         if (epstat & GR_EPSTAT_B0)
1796                 bytes += (epstat & GR_EPSTAT_B0CNT_MASK) >> GR_EPSTAT_B0CNT_POS;
1797         if (epstat & GR_EPSTAT_B1)
1798                 bytes += (epstat & GR_EPSTAT_B1CNT_MASK) >> GR_EPSTAT_B1CNT_POS;
1799 
1800         return bytes;
1801 }
1802 
1803 
1804 /* Empty data from internal buffers of an endpoint. */
1805 static void gr_fifo_flush(struct usb_ep *_ep)
1806 {
1807         struct gr_ep *ep;
1808         u32 epctrl;
1809 
1810         if (!_ep)
1811                 return;
1812         ep = container_of(_ep, struct gr_ep, ep);
1813         dev_vdbg(ep->dev->dev, "EP: flush fifo %s\n", ep->ep.name);
1814 
1815         spin_lock(&ep->dev->lock);
1816 
1817         epctrl = gr_read32(&ep->regs->epctrl);
1818         epctrl |= GR_EPCTRL_CB;
1819         gr_write32(&ep->regs->epctrl, epctrl);
1820 
1821         spin_unlock(&ep->dev->lock);
1822 }
1823 
1824 static const struct usb_ep_ops gr_ep_ops = {
1825         .enable         = gr_ep_enable,
1826         .disable        = gr_ep_disable,
1827 
1828         .alloc_request  = gr_alloc_request,
1829         .free_request   = gr_free_request,
1830 
1831         .queue          = gr_queue_ext,
1832         .dequeue        = gr_dequeue,
1833 
1834         .set_halt       = gr_set_halt,
1835         .set_wedge      = gr_set_wedge,
1836         .fifo_status    = gr_fifo_status,
1837         .fifo_flush     = gr_fifo_flush,
1838 };
1839 
1840 /* ---------------------------------------------------------------------- */
1841 /* USB Gadget ops */
1842 
1843 static int gr_get_frame(struct usb_gadget *_gadget)
1844 {
1845         struct gr_udc *dev;
1846 
1847         if (!_gadget)
1848                 return -ENODEV;
1849         dev = container_of(_gadget, struct gr_udc, gadget);
1850         return gr_read32(&dev->regs->status) & GR_STATUS_FN_MASK;
1851 }
1852 
1853 static int gr_wakeup(struct usb_gadget *_gadget)
1854 {
1855         struct gr_udc *dev;
1856 
1857         if (!_gadget)
1858                 return -ENODEV;
1859         dev = container_of(_gadget, struct gr_udc, gadget);
1860 
1861         /* Remote wakeup feature not enabled by host*/
1862         if (!dev->remote_wakeup)
1863                 return -EINVAL;
1864 
1865         spin_lock(&dev->lock);
1866 
1867         gr_write32(&dev->regs->control,
1868                    gr_read32(&dev->regs->control) | GR_CONTROL_RW);
1869 
1870         spin_unlock(&dev->lock);
1871 
1872         return 0;
1873 }
1874 
1875 static int gr_pullup(struct usb_gadget *_gadget, int is_on)
1876 {
1877         struct gr_udc *dev;
1878         u32 control;
1879 
1880         if (!_gadget)
1881                 return -ENODEV;
1882         dev = container_of(_gadget, struct gr_udc, gadget);
1883 
1884         spin_lock(&dev->lock);
1885 
1886         control = gr_read32(&dev->regs->control);
1887         if (is_on)
1888                 control |= GR_CONTROL_EP;
1889         else
1890                 control &= ~GR_CONTROL_EP;
1891         gr_write32(&dev->regs->control, control);
1892 
1893         spin_unlock(&dev->lock);
1894 
1895         return 0;
1896 }
1897 
1898 static int gr_udc_start(struct usb_gadget *gadget,
1899                         struct usb_gadget_driver *driver)
1900 {
1901         struct gr_udc *dev = to_gr_udc(gadget);
1902 
1903         spin_lock(&dev->lock);
1904 
1905         /* Hook up the driver */
1906         driver->driver.bus = NULL;
1907         dev->driver = driver;
1908 
1909         /* Get ready for host detection */
1910         gr_enable_vbus_detect(dev);
1911 
1912         spin_unlock(&dev->lock);
1913 
1914         return 0;
1915 }
1916 
1917 static int gr_udc_stop(struct usb_gadget *gadget)
1918 {
1919         struct gr_udc *dev = to_gr_udc(gadget);
1920         unsigned long flags;
1921 
1922         spin_lock_irqsave(&dev->lock, flags);
1923 
1924         dev->driver = NULL;
1925         gr_stop_activity(dev);
1926 
1927         spin_unlock_irqrestore(&dev->lock, flags);
1928 
1929         return 0;
1930 }
1931 
1932 static const struct usb_gadget_ops gr_ops = {
1933         .get_frame      = gr_get_frame,
1934         .wakeup         = gr_wakeup,
1935         .pullup         = gr_pullup,
1936         .udc_start      = gr_udc_start,
1937         .udc_stop       = gr_udc_stop,
1938         /* Other operations not supported */
1939 };
1940 
1941 /* ---------------------------------------------------------------------- */
1942 /* Module probe, removal and of-matching */
1943 
1944 static const char * const onames[] = {
1945         "ep0out", "ep1out", "ep2out", "ep3out", "ep4out", "ep5out",
1946         "ep6out", "ep7out", "ep8out", "ep9out", "ep10out", "ep11out",
1947         "ep12out", "ep13out", "ep14out", "ep15out"
1948 };
1949 
1950 static const char * const inames[] = {
1951         "ep0in", "ep1in", "ep2in", "ep3in", "ep4in", "ep5in",
1952         "ep6in", "ep7in", "ep8in", "ep9in", "ep10in", "ep11in",
1953         "ep12in", "ep13in", "ep14in", "ep15in"
1954 };
1955 
1956 /* Must be called with dev->lock held */
1957 static int gr_ep_init(struct gr_udc *dev, int num, int is_in, u32 maxplimit)
1958 {
1959         struct gr_ep *ep;
1960         struct gr_request *req;
1961         struct usb_request *_req;
1962         void *buf;
1963 
1964         if (is_in) {
1965                 ep = &dev->epi[num];
1966                 ep->ep.name = inames[num];
1967                 ep->regs = &dev->regs->epi[num];
1968         } else {
1969                 ep = &dev->epo[num];
1970                 ep->ep.name = onames[num];
1971                 ep->regs = &dev->regs->epo[num];
1972         }
1973 
1974         gr_ep_reset(ep);
1975         ep->num = num;
1976         ep->is_in = is_in;
1977         ep->dev = dev;
1978         ep->ep.ops = &gr_ep_ops;
1979         INIT_LIST_HEAD(&ep->queue);
1980 
1981         if (num == 0) {
1982                 _req = gr_alloc_request(&ep->ep, GFP_ATOMIC);
1983                 buf = devm_kzalloc(dev->dev, PAGE_SIZE, GFP_DMA | GFP_ATOMIC);
1984                 if (!_req || !buf) {
1985                         /* possible _req freed by gr_probe via gr_remove */
1986                         return -ENOMEM;
1987                 }
1988 
1989                 req = container_of(_req, struct gr_request, req);
1990                 req->req.buf = buf;
1991                 req->req.length = MAX_CTRL_PL_SIZE;
1992 
1993                 if (is_in)
1994                         dev->ep0reqi = req; /* Complete gets set as used */
1995                 else
1996                         dev->ep0reqo = req; /* Completion treated separately */
1997 
1998                 usb_ep_set_maxpacket_limit(&ep->ep, MAX_CTRL_PL_SIZE);
1999                 ep->bytes_per_buffer = MAX_CTRL_PL_SIZE;
2000 
2001                 ep->ep.caps.type_control = true;
2002         } else {
2003                 usb_ep_set_maxpacket_limit(&ep->ep, (u16)maxplimit);
2004                 list_add_tail(&ep->ep.ep_list, &dev->gadget.ep_list);
2005 
2006                 ep->ep.caps.type_iso = true;
2007                 ep->ep.caps.type_bulk = true;
2008                 ep->ep.caps.type_int = true;
2009         }
2010         list_add_tail(&ep->ep_list, &dev->ep_list);
2011 
2012         if (is_in)
2013                 ep->ep.caps.dir_in = true;
2014         else
2015                 ep->ep.caps.dir_out = true;
2016 
2017         ep->tailbuf = dma_alloc_coherent(dev->dev, ep->ep.maxpacket_limit,
2018                                          &ep->tailbuf_paddr, GFP_ATOMIC);
2019         if (!ep->tailbuf)
2020                 return -ENOMEM;
2021 
2022         return 0;
2023 }
2024 
2025 /* Must be called with dev->lock held */
2026 static int gr_udc_init(struct gr_udc *dev)
2027 {
2028         struct device_node *np = dev->dev->of_node;
2029         u32 epctrl_val;
2030         u32 dmactrl_val;
2031         int i;
2032         int ret = 0;
2033         u32 bufsize;
2034 
2035         gr_set_address(dev, 0);
2036 
2037         INIT_LIST_HEAD(&dev->gadget.ep_list);
2038         dev->gadget.speed = USB_SPEED_UNKNOWN;
2039         dev->gadget.ep0 = &dev->epi[0].ep;
2040 
2041         INIT_LIST_HEAD(&dev->ep_list);
2042         gr_set_ep0state(dev, GR_EP0_DISCONNECT);
2043 
2044         for (i = 0; i < dev->nepo; i++) {
2045                 if (of_property_read_u32_index(np, "epobufsizes", i, &bufsize))
2046                         bufsize = 1024;
2047                 ret = gr_ep_init(dev, i, 0, bufsize);
2048                 if (ret)
2049                         return ret;
2050         }
2051 
2052         for (i = 0; i < dev->nepi; i++) {
2053                 if (of_property_read_u32_index(np, "epibufsizes", i, &bufsize))
2054                         bufsize = 1024;
2055                 ret = gr_ep_init(dev, i, 1, bufsize);
2056                 if (ret)
2057                         return ret;
2058         }
2059 
2060         /* Must be disabled by default */
2061         dev->remote_wakeup = 0;
2062 
2063         /* Enable ep0out and ep0in */
2064         epctrl_val = (MAX_CTRL_PL_SIZE << GR_EPCTRL_MAXPL_POS) | GR_EPCTRL_EV;
2065         dmactrl_val = GR_DMACTRL_IE | GR_DMACTRL_AI;
2066         gr_write32(&dev->epo[0].regs->epctrl, epctrl_val);
2067         gr_write32(&dev->epi[0].regs->epctrl, epctrl_val | GR_EPCTRL_PI);
2068         gr_write32(&dev->epo[0].regs->dmactrl, dmactrl_val);
2069         gr_write32(&dev->epi[0].regs->dmactrl, dmactrl_val);
2070 
2071         return 0;
2072 }
2073 
2074 static void gr_ep_remove(struct gr_udc *dev, int num, int is_in)
2075 {
2076         struct gr_ep *ep;
2077 
2078         if (is_in)
2079                 ep = &dev->epi[num];
2080         else
2081                 ep = &dev->epo[num];
2082 
2083         if (ep->tailbuf)
2084                 dma_free_coherent(dev->dev, ep->ep.maxpacket_limit,
2085                                   ep->tailbuf, ep->tailbuf_paddr);
2086 }
2087 
2088 static int gr_remove(struct platform_device *pdev)
2089 {
2090         struct gr_udc *dev = platform_get_drvdata(pdev);
2091         int i;
2092 
2093         if (dev->added)
2094                 usb_del_gadget_udc(&dev->gadget); /* Shuts everything down */
2095         if (dev->driver)
2096                 return -EBUSY;
2097 
2098         gr_dfs_delete(dev);
2099         dma_pool_destroy(dev->desc_pool);
2100         platform_set_drvdata(pdev, NULL);
2101 
2102         gr_free_request(&dev->epi[0].ep, &dev->ep0reqi->req);
2103         gr_free_request(&dev->epo[0].ep, &dev->ep0reqo->req);
2104 
2105         for (i = 0; i < dev->nepo; i++)
2106                 gr_ep_remove(dev, i, 0);
2107         for (i = 0; i < dev->nepi; i++)
2108                 gr_ep_remove(dev, i, 1);
2109 
2110         return 0;
2111 }
2112 static int gr_request_irq(struct gr_udc *dev, int irq)
2113 {
2114         return devm_request_threaded_irq(dev->dev, irq, gr_irq, gr_irq_handler,
2115                                          IRQF_SHARED, driver_name, dev);
2116 }
2117 
2118 static int gr_probe(struct platform_device *pdev)
2119 {
2120         struct gr_udc *dev;
2121         struct resource *res;
2122         struct gr_regs __iomem *regs;
2123         int retval;
2124         u32 status;
2125 
2126         dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
2127         if (!dev)
2128                 return -ENOMEM;
2129         dev->dev = &pdev->dev;
2130 
2131         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2132         regs = devm_ioremap_resource(dev->dev, res);
2133         if (IS_ERR(regs))
2134                 return PTR_ERR(regs);
2135 
2136         dev->irq = platform_get_irq(pdev, 0);
2137         if (dev->irq <= 0)
2138                 return -ENODEV;
2139 
2140         /* Some core configurations has separate irqs for IN and OUT events */
2141         dev->irqi = platform_get_irq(pdev, 1);
2142         if (dev->irqi > 0) {
2143                 dev->irqo = platform_get_irq(pdev, 2);
2144                 if (dev->irqo <= 0)
2145                         return -ENODEV;
2146         } else {
2147                 dev->irqi = 0;
2148         }
2149 
2150         dev->gadget.name = driver_name;
2151         dev->gadget.max_speed = USB_SPEED_HIGH;
2152         dev->gadget.ops = &gr_ops;
2153 
2154         spin_lock_init(&dev->lock);
2155         dev->regs = regs;
2156 
2157         platform_set_drvdata(pdev, dev);
2158 
2159         /* Determine number of endpoints and data interface mode */
2160         status = gr_read32(&dev->regs->status);
2161         dev->nepi = ((status & GR_STATUS_NEPI_MASK) >> GR_STATUS_NEPI_POS) + 1;
2162         dev->nepo = ((status & GR_STATUS_NEPO_MASK) >> GR_STATUS_NEPO_POS) + 1;
2163 
2164         if (!(status & GR_STATUS_DM)) {
2165                 dev_err(dev->dev, "Slave mode cores are not supported\n");
2166                 return -ENODEV;
2167         }
2168 
2169         /* --- Effects of the following calls might need explicit cleanup --- */
2170 
2171         /* Create DMA pool for descriptors */
2172         dev->desc_pool = dma_pool_create("desc_pool", dev->dev,
2173                                          sizeof(struct gr_dma_desc), 4, 0);
2174         if (!dev->desc_pool) {
2175                 dev_err(dev->dev, "Could not allocate DMA pool");
2176                 return -ENOMEM;
2177         }
2178 
2179         /* Inside lock so that no gadget can use this udc until probe is done */
2180         retval = usb_add_gadget_udc(dev->dev, &dev->gadget);
2181         if (retval) {
2182                 dev_err(dev->dev, "Could not add gadget udc");
2183                 goto out;
2184         }
2185         dev->added = 1;
2186 
2187         spin_lock(&dev->lock);
2188 
2189         retval = gr_udc_init(dev);
2190         if (retval) {
2191                 spin_unlock(&dev->lock);
2192                 goto out;
2193         }
2194 
2195         /* Clear all interrupt enables that might be left on since last boot */
2196         gr_disable_interrupts_and_pullup(dev);
2197 
2198         spin_unlock(&dev->lock);
2199 
2200         gr_dfs_create(dev);
2201 
2202         retval = gr_request_irq(dev, dev->irq);
2203         if (retval) {
2204                 dev_err(dev->dev, "Failed to request irq %d\n", dev->irq);
2205                 goto out;
2206         }
2207 
2208         if (dev->irqi) {
2209                 retval = gr_request_irq(dev, dev->irqi);
2210                 if (retval) {
2211                         dev_err(dev->dev, "Failed to request irqi %d\n",
2212                                 dev->irqi);
2213                         goto out;
2214                 }
2215                 retval = gr_request_irq(dev, dev->irqo);
2216                 if (retval) {
2217                         dev_err(dev->dev, "Failed to request irqo %d\n",
2218                                 dev->irqo);
2219                         goto out;
2220                 }
2221         }
2222 
2223         if (dev->irqi)
2224                 dev_info(dev->dev, "regs: %p, irqs %d, %d, %d\n", dev->regs,
2225                          dev->irq, dev->irqi, dev->irqo);
2226         else
2227                 dev_info(dev->dev, "regs: %p, irq %d\n", dev->regs, dev->irq);
2228 
2229 out:
2230         if (retval)
2231                 gr_remove(pdev);
2232 
2233         return retval;
2234 }
2235 
2236 static const struct of_device_id gr_match[] = {
2237         {.name = "GAISLER_USBDC"},
2238         {.name = "01_021"},
2239         {},
2240 };
2241 MODULE_DEVICE_TABLE(of, gr_match);
2242 
2243 static struct platform_driver gr_driver = {
2244         .driver = {
2245                 .name = DRIVER_NAME,
2246                 .of_match_table = gr_match,
2247         },
2248         .probe = gr_probe,
2249         .remove = gr_remove,
2250 };
2251 module_platform_driver(gr_driver);
2252 
2253 MODULE_AUTHOR("Aeroflex Gaisler AB.");
2254 MODULE_DESCRIPTION(DRIVER_DESC);
2255 MODULE_LICENSE("GPL");

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