drivers/usb/gadget/udc/goku_udc.c

   1 /*
   2  * Toshiba TC86C001 ("Goku-S") USB Device Controller driver
   3  *
   4  * Copyright (C) 2000-2002 Lineo
   5  *      by Stuart Lynne, Tom Rushworth, and Bruce Balden
   6  * Copyright (C) 2002 Toshiba Corporation
   7  * Copyright (C) 2003 MontaVista Software (source@mvista.com)
   8  *
   9  * This file is licensed under the terms of the GNU General Public
  10  * License version 2.  This program is licensed "as is" without any
  11  * warranty of any kind, whether express or implied.
  12  */
  13
  14 /*
  15  * This device has ep0 and three semi-configurable bulk/interrupt endpoints.
  16  *
  17  *  - Endpoint numbering is fixed: ep{1,2,3}-bulk
  18  *  - Gadget drivers can choose ep maxpacket (8/16/32/64)
  19  *  - Gadget drivers can choose direction (IN, OUT)
  20  *  - DMA works with ep1 (OUT transfers) and ep2 (IN transfers).
  21  */
  22
  23 // #define      VERBOSE         /* extra debug messages (success too) */
  24 // #define      USB_TRACE       /* packet-level success messages */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/pci.h>
  29 #include <linux/delay.h>
  30 #include <linux/ioport.h>
  31 #include <linux/slab.h>
  32 #include <linux/errno.h>
  33 #include <linux/timer.h>
  34 #include <linux/list.h>
  35 #include <linux/interrupt.h>
  36 #include <linux/proc_fs.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/device.h>
  39 #include <linux/usb/ch9.h>
  40 #include <linux/usb/gadget.h>
  41 #include <linux/prefetch.h>
  42
  43 #include <asm/byteorder.h>
  44 #include <asm/io.h>
  45 #include <asm/irq.h>
  46 #include <asm/unaligned.h>
  47
  48
  49 #include "goku_udc.h"
  50
  51 #define DRIVER_DESC             "TC86C001 USB Device Controller"
  52 #define DRIVER_VERSION          "30-Oct 2003"
  53
  54 static const char driver_name [] = "goku_udc";
  55 static const char driver_desc [] = DRIVER_DESC;
  56
  57 MODULE_AUTHOR("source@mvista.com");
  58 MODULE_DESCRIPTION(DRIVER_DESC);
  59 MODULE_LICENSE("GPL");
  60
  61
  62 /*
  63  * IN dma behaves ok under testing, though the IN-dma abort paths don't
  64  * seem to behave quite as expected.  Used by default.
  65  *
  66  * OUT dma documents design problems handling the common "short packet"
  67  * transfer termination policy; it couldn't be enabled by default, even
  68  * if the OUT-dma abort problems had a resolution.
  69  */
  70 static unsigned use_dma = 1;
  71
  72 #if 0
  73 //#include <linux/moduleparam.h>
  74 /* "modprobe goku_udc use_dma=1" etc
  75  *      0 to disable dma
  76  *      1 to use IN dma only (normal operation)
  77  *      2 to use IN and OUT dma
  78  */
  79 module_param(use_dma, uint, S_IRUGO);
  80 #endif
  81
  82 /*-------------------------------------------------------------------------*/
  83
  84 static void nuke(struct goku_ep *, int status);
  85
  86 static inline void
  87 command(struct goku_udc_regs __iomem *regs, int command, unsigned epnum)
  88 {
  89         writel(COMMAND_EP(epnum) | command, &regs->Command);
  90         udelay(300);
  91 }
  92
  93 static int
  94 goku_ep_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc)
  95 {
  96         struct goku_udc *dev;
  97         struct goku_ep  *ep;
  98         u32             mode;
  99         u16             max;
 100         unsigned long   flags;
 101
 102         ep = container_of(_ep, struct goku_ep, ep);
 103         if (!_ep || !desc
 104                         || desc->bDescriptorType != USB_DT_ENDPOINT)
 105                 return -EINVAL;
 106         dev = ep->dev;
 107         if (ep == &dev->ep[0])
 108                 return -EINVAL;
 109         if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)
 110                 return -ESHUTDOWN;
 111         if (ep->num != usb_endpoint_num(desc))
 112                 return -EINVAL;
 113
 114         switch (usb_endpoint_type(desc)) {
 115         case USB_ENDPOINT_XFER_BULK:
 116         case USB_ENDPOINT_XFER_INT:
 117                 break;
 118         default:
 119                 return -EINVAL;
 120         }
 121
 122         if ((readl(ep->reg_status) & EPxSTATUS_EP_MASK)
 123                         != EPxSTATUS_EP_INVALID)
 124                 return -EBUSY;
 125
 126         /* enabling the no-toggle interrupt mode would need an api hook */
 127         mode = 0;
 128         max = get_unaligned_le16(&desc->wMaxPacketSize);
 129         switch (max) {
 130         case 64:        mode++;
 131         case 32:        mode++;
 132         case 16:        mode++;
 133         case 8:         mode <<= 3;
 134                         break;
 135         default:
 136                 return -EINVAL;
 137         }
 138         mode |= 2 << 1;         /* bulk, or intr-with-toggle */
 139
 140         /* ep1/ep2 dma direction is chosen early; it works in the other
 141          * direction, with pio.  be cautious with out-dma.
 142          */
 143         ep->is_in = usb_endpoint_dir_in(desc);
 144         if (ep->is_in) {
 145                 mode |= 1;
 146                 ep->dma = (use_dma != 0) && (ep->num == UDC_MSTRD_ENDPOINT);
 147         } else {
 148                 ep->dma = (use_dma == 2) && (ep->num == UDC_MSTWR_ENDPOINT);
 149                 if (ep->dma)
 150                         DBG(dev, "%s out-dma hides short packets\n",
 151                                 ep->ep.name);
 152         }
 153
 154         spin_lock_irqsave(&ep->dev->lock, flags);
 155
 156         /* ep1 and ep2 can do double buffering and/or dma */
 157         if (ep->num < 3) {
 158                 struct goku_udc_regs __iomem    *regs = ep->dev->regs;
 159                 u32                             tmp;
 160
 161                 /* double buffer except (for now) with pio in */
 162                 tmp = ((ep->dma || !ep->is_in)
 163                                 ? 0x10  /* double buffered */
 164                                 : 0x11  /* single buffer */
 165                         ) << ep->num;
 166                 tmp |= readl(&regs->EPxSingle);
 167                 writel(tmp, &regs->EPxSingle);
 168
 169                 tmp = (ep->dma ? 0x10/*dma*/ : 0x11/*pio*/) << ep->num;
 170                 tmp |= readl(&regs->EPxBCS);
 171                 writel(tmp, &regs->EPxBCS);
 172         }
 173         writel(mode, ep->reg_mode);
 174         command(ep->dev->regs, COMMAND_RESET, ep->num);
 175         ep->ep.maxpacket = max;
 176         ep->stopped = 0;
 177         ep->ep.desc = desc;
 178         spin_unlock_irqrestore(&ep->dev->lock, flags);
 179
 180         DBG(dev, "enable %s %s %s maxpacket %u\n", ep->ep.name,
 181                 ep->is_in ? "IN" : "OUT",
 182                 ep->dma ? "dma" : "pio",
 183                 max);
 184
 185         return 0;
 186 }
 187
 188 static void ep_reset(struct goku_udc_regs __iomem *regs, struct goku_ep *ep)
 189 {
 190         struct goku_udc         *dev = ep->dev;
 191
 192         if (regs) {
 193                 command(regs, COMMAND_INVALID, ep->num);
 194                 if (ep->num) {
 195                         if (ep->num == UDC_MSTWR_ENDPOINT)
 196                                 dev->int_enable &= ~(INT_MSTWREND
 197                                                         |INT_MSTWRTMOUT);
 198                         else if (ep->num == UDC_MSTRD_ENDPOINT)
 199                                 dev->int_enable &= ~INT_MSTRDEND;
 200                         dev->int_enable &= ~INT_EPxDATASET (ep->num);
 201                 } else
 202                         dev->int_enable &= ~INT_EP0;
 203                 writel(dev->int_enable, &regs->int_enable);
 204                 readl(&regs->int_enable);
 205                 if (ep->num < 3) {
 206                         struct goku_udc_regs __iomem    *r = ep->dev->regs;
 207                         u32                             tmp;
 208
 209                         tmp = readl(&r->EPxSingle);
 210                         tmp &= ~(0x11 << ep->num);
 211                         writel(tmp, &r->EPxSingle);
 212
 213                         tmp = readl(&r->EPxBCS);
 214                         tmp &= ~(0x11 << ep->num);
 215                         writel(tmp, &r->EPxBCS);
 216                 }
 217                 /* reset dma in case we're still using it */
 218                 if (ep->dma) {
 219                         u32     master;
 220
 221                         master = readl(&regs->dma_master) & MST_RW_BITS;
 222                         if (ep->num == UDC_MSTWR_ENDPOINT) {
 223                                 master &= ~MST_W_BITS;
 224                                 master |= MST_WR_RESET;
 225                         } else {
 226                                 master &= ~MST_R_BITS;
 227                                 master |= MST_RD_RESET;
 228                         }
 229                         writel(master, &regs->dma_master);
 230                 }
 231         }
 232
 233         usb_ep_set_maxpacket_limit(&ep->ep, MAX_FIFO_SIZE);
 234         ep->ep.desc = NULL;
 235         ep->stopped = 1;
 236         ep->irqs = 0;
 237         ep->dma = 0;
 238 }
 239
 240 static int goku_ep_disable(struct usb_ep *_ep)
 241 {
 242         struct goku_ep  *ep;
 243         struct goku_udc *dev;
 244         unsigned long   flags;
 245
 246         ep = container_of(_ep, struct goku_ep, ep);
 247         if (!_ep || !ep->ep.desc)
 248                 return -ENODEV;
 249         dev = ep->dev;
 250         if (dev->ep0state == EP0_SUSPEND)
 251                 return -EBUSY;
 252
 253         VDBG(dev, "disable %s\n", _ep->name);
 254
 255         spin_lock_irqsave(&dev->lock, flags);
 256         nuke(ep, -ESHUTDOWN);
 257         ep_reset(dev->regs, ep);
 258         spin_unlock_irqrestore(&dev->lock, flags);
 259
 260         return 0;
 261 }
 262
 263 /*-------------------------------------------------------------------------*/
 264
 265 static struct usb_request *
 266 goku_alloc_request(struct usb_ep *_ep, gfp_t gfp_flags)
 267 {
 268         struct goku_request     *req;
 269
 270         if (!_ep)
 271                 return NULL;
 272         req = kzalloc(sizeof *req, gfp_flags);
 273         if (!req)
 274                 return NULL;
 275
 276         INIT_LIST_HEAD(&req->queue);
 277         return &req->req;
 278 }
 279
 280 static void
 281 goku_free_request(struct usb_ep *_ep, struct usb_request *_req)
 282 {
 283         struct goku_request     *req;
 284
 285         if (!_ep || !_req)
 286                 return;
 287
 288         req = container_of(_req, struct goku_request, req);
 289         WARN_ON(!list_empty(&req->queue));
 290         kfree(req);
 291 }
 292
 293 /*-------------------------------------------------------------------------*/
 294
 295 static void
 296 done(struct goku_ep *ep, struct goku_request *req, int status)
 297 {
 298         struct goku_udc         *dev;
 299         unsigned                stopped = ep->stopped;
 300
 301         list_del_init(&req->queue);
 302
 303         if (likely(req->req.status == -EINPROGRESS))
 304                 req->req.status = status;
 305         else
 306                 status = req->req.status;
 307
 308         dev = ep->dev;
 309
 310         if (ep->dma)
 311                 usb_gadget_unmap_request(&dev->gadget, &req->req, ep->is_in);
 312
 313 #ifndef USB_TRACE
 314         if (status && status != -ESHUTDOWN)
 315 #endif
 316                 VDBG(dev, "complete %s req %p stat %d len %u/%u\n",
 317                         ep->ep.name, &req->req, status,
 318                         req->req.actual, req->req.length);
 319
 320         /* don't modify queue heads during completion callback */
 321         ep->stopped = 1;
 322         spin_unlock(&dev->lock);
 323         usb_gadget_giveback_request(&ep->ep, &req->req);
 324         spin_lock(&dev->lock);
 325         ep->stopped = stopped;
 326 }
 327
 328 /*-------------------------------------------------------------------------*/
 329
 330 static inline int
 331 write_packet(u32 __iomem *fifo, u8 *buf, struct goku_request *req, unsigned max)
 332 {
 333         unsigned        length, count;
 334
 335         length = min(req->req.length - req->req.actual, max);
 336         req->req.actual += length;
 337
 338         count = length;
 339         while (likely(count--))
 340                 writel(*buf++, fifo);
 341         return length;
 342 }
 343
 344 // return:  0 = still running, 1 = completed, negative = errno
 345 static int write_fifo(struct goku_ep *ep, struct goku_request *req)
 346 {
 347         struct goku_udc *dev = ep->dev;
 348         u32             tmp;
 349         u8              *buf;
 350         unsigned        count;
 351         int             is_last;
 352
 353         tmp = readl(&dev->regs->DataSet);
 354         buf = req->req.buf + req->req.actual;
 355         prefetch(buf);
 356
 357         dev = ep->dev;
 358         if (unlikely(ep->num == 0 && dev->ep0state != EP0_IN))
 359                 return -EL2HLT;
 360
 361         /* NOTE:  just single-buffered PIO-IN for now.  */
 362         if (unlikely((tmp & DATASET_A(ep->num)) != 0))
 363                 return 0;
 364
 365         /* clear our "packet available" irq */
 366         if (ep->num != 0)
 367                 writel(~INT_EPxDATASET(ep->num), &dev->regs->int_status);
 368
 369         count = write_packet(ep->reg_fifo, buf, req, ep->ep.maxpacket);
 370
 371         /* last packet often short (sometimes a zlp, especially on ep0) */
 372         if (unlikely(count != ep->ep.maxpacket)) {
 373                 writel(~(1<<ep->num), &dev->regs->EOP);
 374                 if (ep->num == 0) {
 375                         dev->ep[0].stopped = 1;
 376                         dev->ep0state = EP0_STATUS;
 377                 }
 378                 is_last = 1;
 379         } else {
 380                 if (likely(req->req.length != req->req.actual)
 381                                 || req->req.zero)
 382                         is_last = 0;
 383                 else
 384                         is_last = 1;
 385         }
 386 #if 0           /* printk seemed to trash is_last...*/
 387 //#ifdef USB_TRACE
 388         VDBG(dev, "wrote %s %u bytes%s IN %u left %p\n",
 389                 ep->ep.name, count, is_last ? "/last" : "",
 390                 req->req.length - req->req.actual, req);
 391 #endif
 392
 393         /* requests complete when all IN data is in the FIFO,
 394          * or sometimes later, if a zlp was needed.
 395          */
 396         if (is_last) {
 397                 done(ep, req, 0);
 398                 return 1;
 399         }
 400
 401         return 0;
 402 }
 403
 404 static int read_fifo(struct goku_ep *ep, struct goku_request *req)
 405 {
 406         struct goku_udc_regs __iomem    *regs;
 407         u32                             size, set;
 408         u8                              *buf;
 409         unsigned                        bufferspace, is_short, dbuff;
 410
 411         regs = ep->dev->regs;
 412 top:
 413         buf = req->req.buf + req->req.actual;
 414         prefetchw(buf);
 415
 416         if (unlikely(ep->num == 0 && ep->dev->ep0state != EP0_OUT))
 417                 return -EL2HLT;
 418
 419         dbuff = (ep->num == 1 || ep->num == 2);
 420         do {
 421                 /* ack dataset irq matching the status we'll handle */
 422                 if (ep->num != 0)
 423                         writel(~INT_EPxDATASET(ep->num), &regs->int_status);
 424
 425                 set = readl(&regs->DataSet) & DATASET_AB(ep->num);
 426                 size = readl(&regs->EPxSizeLA[ep->num]);
 427                 bufferspace = req->req.length - req->req.actual;
 428
 429                 /* usually do nothing without an OUT packet */
 430                 if (likely(ep->num != 0 || bufferspace != 0)) {
 431                         if (unlikely(set == 0))
 432                                 break;
 433                         /* use ep1/ep2 double-buffering for OUT */
 434                         if (!(size & PACKET_ACTIVE))
 435                                 size = readl(&regs->EPxSizeLB[ep->num]);
 436                         if (!(size & PACKET_ACTIVE))    /* "can't happen" */
 437                                 break;
 438                         size &= DATASIZE;       /* EPxSizeH == 0 */
 439
 440                 /* ep0out no-out-data case for set_config, etc */
 441                 } else
 442                         size = 0;
 443
 444                 /* read all bytes from this packet */
 445                 req->req.actual += size;
 446                 is_short = (size < ep->ep.maxpacket);
 447 #ifdef USB_TRACE
 448                 VDBG(ep->dev, "read %s %u bytes%s OUT req %p %u/%u\n",
 449                         ep->ep.name, size, is_short ? "/S" : "",
 450                         req, req->req.actual, req->req.length);
 451 #endif
 452                 while (likely(size-- != 0)) {
 453                         u8      byte = (u8) readl(ep->reg_fifo);
 454
 455                         if (unlikely(bufferspace == 0)) {
 456                                 /* this happens when the driver's buffer
 457                                  * is smaller than what the host sent.
 458                                  * discard the extra data in this packet.
 459                                  */
 460                                 if (req->req.status != -EOVERFLOW)
 461                                         DBG(ep->dev, "%s overflow %u\n",
 462                                                 ep->ep.name, size);
 463                                 req->req.status = -EOVERFLOW;
 464                         } else {
 465                                 *buf++ = byte;
 466                                 bufferspace--;
 467                         }
 468                 }
 469
 470                 /* completion */
 471                 if (unlikely(is_short || req->req.actual == req->req.length)) {
 472                         if (unlikely(ep->num == 0)) {
 473                                 /* non-control endpoints now usable? */
 474                                 if (ep->dev->req_config)
 475                                         writel(ep->dev->configured
 476                                                         ? USBSTATE_CONFIGURED
 477                                                         : 0,
 478                                                 &regs->UsbState);
 479                                 /* ep0out status stage */
 480                                 writel(~(1<<0), &regs->EOP);
 481                                 ep->stopped = 1;
 482                                 ep->dev->ep0state = EP0_STATUS;
 483                         }
 484                         done(ep, req, 0);
 485
 486                         /* empty the second buffer asap */
 487                         if (dbuff && !list_empty(&ep->queue)) {
 488                                 req = list_entry(ep->queue.next,
 489                                                 struct goku_request, queue);
 490                                 goto top;
 491                         }
 492                         return 1;
 493                 }
 494         } while (dbuff);
 495         return 0;
 496 }
 497
 498 static inline void
 499 pio_irq_enable(struct goku_udc *dev,
 500                 struct goku_udc_regs __iomem *regs, int epnum)
 501 {
 502         dev->int_enable |= INT_EPxDATASET (epnum);
 503         writel(dev->int_enable, &regs->int_enable);
 504         /* write may still be posted */
 505 }
 506
 507 static inline void
 508 pio_irq_disable(struct goku_udc *dev,
 509                 struct goku_udc_regs __iomem *regs, int epnum)
 510 {
 511         dev->int_enable &= ~INT_EPxDATASET (epnum);
 512         writel(dev->int_enable, &regs->int_enable);
 513         /* write may still be posted */
 514 }
 515
 516 static inline void
 517 pio_advance(struct goku_ep *ep)
 518 {
 519         struct goku_request     *req;
 520
 521         if (unlikely(list_empty (&ep->queue)))
 522                 return;
 523         req = list_entry(ep->queue.next, struct goku_request, queue);
 524         (ep->is_in ? write_fifo : read_fifo)(ep, req);
 525 }
 526
 527
 528 /*-------------------------------------------------------------------------*/
 529
 530 // return:  0 = q running, 1 = q stopped, negative = errno
 531 static int start_dma(struct goku_ep *ep, struct goku_request *req)
 532 {
 533         struct goku_udc_regs __iomem    *regs = ep->dev->regs;
 534         u32                             master;
 535         u32                             start = req->req.dma;
 536         u32                             end = start + req->req.length - 1;
 537
 538         master = readl(&regs->dma_master) & MST_RW_BITS;
 539
 540         /* re-init the bits affecting IN dma; careful with zlps */
 541         if (likely(ep->is_in)) {
 542                 if (unlikely(master & MST_RD_ENA)) {
 543                         DBG (ep->dev, "start, IN active dma %03x!!\n",
 544                                 master);
 545 //                      return -EL2HLT;
 546                 }
 547                 writel(end, &regs->in_dma_end);
 548                 writel(start, &regs->in_dma_start);
 549
 550                 master &= ~MST_R_BITS;
 551                 if (unlikely(req->req.length == 0))
 552                         master = MST_RD_ENA | MST_RD_EOPB;
 553                 else if ((req->req.length % ep->ep.maxpacket) != 0
 554                                         || req->req.zero)
 555                         master = MST_RD_ENA | MST_EOPB_ENA;
 556                 else
 557                         master = MST_RD_ENA | MST_EOPB_DIS;
 558
 559                 ep->dev->int_enable |= INT_MSTRDEND;
 560
 561         /* Goku DMA-OUT merges short packets, which plays poorly with
 562          * protocols where short packets mark the transfer boundaries.
 563          * The chip supports a nonstandard policy with INT_MSTWRTMOUT,
 564          * ending transfers after 3 SOFs; we don't turn it on.
 565          */
 566         } else {
 567                 if (unlikely(master & MST_WR_ENA)) {
 568                         DBG (ep->dev, "start, OUT active dma %03x!!\n",
 569                                 master);
 570 //                      return -EL2HLT;
 571                 }
 572                 writel(end, &regs->out_dma_end);
 573                 writel(start, &regs->out_dma_start);
 574
 575                 master &= ~MST_W_BITS;
 576                 master |= MST_WR_ENA | MST_TIMEOUT_DIS;
 577
 578                 ep->dev->int_enable |= INT_MSTWREND|INT_MSTWRTMOUT;
 579         }
 580
 581         writel(master, &regs->dma_master);
 582         writel(ep->dev->int_enable, &regs->int_enable);
 583         return 0;
 584 }
 585
 586 static void dma_advance(struct goku_udc *dev, struct goku_ep *ep)
 587 {
 588         struct goku_request             *req;
 589         struct goku_udc_regs __iomem    *regs = ep->dev->regs;
 590         u32                             master;
 591
 592         master = readl(&regs->dma_master);
 593
 594         if (unlikely(list_empty(&ep->queue))) {
 595 stop:
 596                 if (ep->is_in)
 597                         dev->int_enable &= ~INT_MSTRDEND;
 598                 else
 599                         dev->int_enable &= ~(INT_MSTWREND|INT_MSTWRTMOUT);
 600                 writel(dev->int_enable, &regs->int_enable);
 601                 return;
 602         }
 603         req = list_entry(ep->queue.next, struct goku_request, queue);
 604
 605         /* normal hw dma completion (not abort) */
 606         if (likely(ep->is_in)) {
 607                 if (unlikely(master & MST_RD_ENA))
 608                         return;
 609                 req->req.actual = readl(&regs->in_dma_current);
 610         } else {
 611                 if (unlikely(master & MST_WR_ENA))
 612                         return;
 613
 614                 /* hardware merges short packets, and also hides packet
 615                  * overruns.  a partial packet MAY be in the fifo here.
 616                  */
 617                 req->req.actual = readl(&regs->out_dma_current);
 618         }
 619         req->req.actual -= req->req.dma;
 620         req->req.actual++;
 621
 622 #ifdef USB_TRACE
 623         VDBG(dev, "done %s %s dma, %u/%u bytes, req %p\n",
 624                 ep->ep.name, ep->is_in ? "IN" : "OUT",
 625                 req->req.actual, req->req.length, req);
 626 #endif
 627         done(ep, req, 0);
 628         if (list_empty(&ep->queue))
 629                 goto stop;
 630         req = list_entry(ep->queue.next, struct goku_request, queue);
 631         (void) start_dma(ep, req);
 632 }
 633
 634 static void abort_dma(struct goku_ep *ep, int status)
 635 {
 636         struct goku_udc_regs __iomem    *regs = ep->dev->regs;
 637         struct goku_request             *req;
 638         u32                             curr, master;
 639
 640         /* NAK future host requests, hoping the implicit delay lets the
 641          * dma engine finish reading (or writing) its latest packet and
 642          * empty the dma buffer (up to 16 bytes).
 643          *
 644          * This avoids needing to clean up a partial packet in the fifo;
 645          * we can't do that for IN without side effects to HALT and TOGGLE.
 646          */
 647         command(regs, COMMAND_FIFO_DISABLE, ep->num);
 648         req = list_entry(ep->queue.next, struct goku_request, queue);
 649         master = readl(&regs->dma_master) & MST_RW_BITS;
 650
 651         /* FIXME using these resets isn't usably documented. this may
 652          * not work unless it's followed by disabling the endpoint.
 653          *
 654          * FIXME the OUT reset path doesn't even behave consistently.
 655          */
 656         if (ep->is_in) {
 657                 if (unlikely((readl(&regs->dma_master) & MST_RD_ENA) == 0))
 658                         goto finished;
 659                 curr = readl(&regs->in_dma_current);
 660
 661                 writel(curr, &regs->in_dma_end);
 662                 writel(curr, &regs->in_dma_start);
 663
 664                 master &= ~MST_R_BITS;
 665                 master |= MST_RD_RESET;
 666                 writel(master, &regs->dma_master);
 667
 668                 if (readl(&regs->dma_master) & MST_RD_ENA)
 669                         DBG(ep->dev, "IN dma active after reset!\n");
 670
 671         } else {
 672                 if (unlikely((readl(&regs->dma_master) & MST_WR_ENA) == 0))
 673                         goto finished;
 674                 curr = readl(&regs->out_dma_current);
 675
 676                 writel(curr, &regs->out_dma_end);
 677                 writel(curr, &regs->out_dma_start);
 678
 679                 master &= ~MST_W_BITS;
 680                 master |= MST_WR_RESET;
 681                 writel(master, &regs->dma_master);
 682
 683                 if (readl(&regs->dma_master) & MST_WR_ENA)
 684                         DBG(ep->dev, "OUT dma active after reset!\n");
 685         }
 686         req->req.actual = (curr - req->req.dma) + 1;
 687         req->req.status = status;
 688
 689         VDBG(ep->dev, "%s %s %s %d/%d\n", __func__, ep->ep.name,
 690                 ep->is_in ? "IN" : "OUT",
 691                 req->req.actual, req->req.length);
 692
 693         command(regs, COMMAND_FIFO_ENABLE, ep->num);
 694
 695         return;
 696
 697 finished:
 698         /* dma already completed; no abort needed */
 699         command(regs, COMMAND_FIFO_ENABLE, ep->num);
 700         req->req.actual = req->req.length;
 701         req->req.status = 0;
 702 }
 703
 704 /*-------------------------------------------------------------------------*/
 705
 706 static int
 707 goku_queue(struct usb_ep *_ep, struct usb_request *_req, gfp_t gfp_flags)
 708 {
 709         struct goku_request     *req;
 710         struct goku_ep          *ep;
 711         struct goku_udc         *dev;
 712         unsigned long           flags;
 713         int                     status;
 714
 715         /* always require a cpu-view buffer so pio works */
 716         req = container_of(_req, struct goku_request, req);
 717         if (unlikely(!_req || !_req->complete
 718                         || !_req->buf || !list_empty(&req->queue)))
 719                 return -EINVAL;
 720         ep = container_of(_ep, struct goku_ep, ep);
 721         if (unlikely(!_ep || (!ep->ep.desc && ep->num != 0)))
 722                 return -EINVAL;
 723         dev = ep->dev;
 724         if (unlikely(!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN))
 725                 return -ESHUTDOWN;
 726
 727         /* can't touch registers when suspended */
 728         if (dev->ep0state == EP0_SUSPEND)
 729                 return -EBUSY;
 730
 731         /* set up dma mapping in case the caller didn't */
 732         if (ep->dma) {
 733                 status = usb_gadget_map_request(&dev->gadget, &req->req,
 734                                 ep->is_in);
 735                 if (status)
 736                         return status;
 737         }
 738
 739 #ifdef USB_TRACE
 740         VDBG(dev, "%s queue req %p, len %u buf %p\n",
 741                         _ep->name, _req, _req->length, _req->buf);
 742 #endif
 743
 744         spin_lock_irqsave(&dev->lock, flags);
 745
 746         _req->status = -EINPROGRESS;
 747         _req->actual = 0;
 748
 749         /* for ep0 IN without premature status, zlp is required and
 750          * writing EOP starts the status stage (OUT).
 751          */
 752         if (unlikely(ep->num == 0 && ep->is_in))
 753                 _req->zero = 1;
 754
 755         /* kickstart this i/o queue? */
 756         status = 0;
 757         if (list_empty(&ep->queue) && likely(!ep->stopped)) {
 758                 /* dma:  done after dma completion IRQ (or error)
 759                  * pio:  done after last fifo operation
 760                  */
 761                 if (ep->dma)
 762                         status = start_dma(ep, req);
 763                 else
 764                         status = (ep->is_in ? write_fifo : read_fifo)(ep, req);
 765
 766                 if (unlikely(status != 0)) {
 767                         if (status > 0)
 768                                 status = 0;
 769                         req = NULL;
 770                 }
 771
 772         } /* else pio or dma irq handler advances the queue. */
 773
 774         if (likely(req != NULL))
 775                 list_add_tail(&req->queue, &ep->queue);
 776
 777         if (likely(!list_empty(&ep->queue))
 778                         && likely(ep->num != 0)
 779                         && !ep->dma
 780                         && !(dev->int_enable & INT_EPxDATASET (ep->num)))
 781                 pio_irq_enable(dev, dev->regs, ep->num);
 782
 783         spin_unlock_irqrestore(&dev->lock, flags);
 784
 785         /* pci writes may still be posted */
 786         return status;
 787 }
 788
 789 /* dequeue ALL requests */
 790 static void nuke(struct goku_ep *ep, int status)
 791 {
 792         struct goku_request     *req;
 793
 794         ep->stopped = 1;
 795         if (list_empty(&ep->queue))
 796                 return;
 797         if (ep->dma)
 798                 abort_dma(ep, status);
 799         while (!list_empty(&ep->queue)) {
 800                 req = list_entry(ep->queue.next, struct goku_request, queue);
 801                 done(ep, req, status);
 802         }
 803 }
 804
 805 /* dequeue JUST ONE request */
 806 static int goku_dequeue(struct usb_ep *_ep, struct usb_request *_req)
 807 {
 808         struct goku_request     *req;
 809         struct goku_ep          *ep;
 810         struct goku_udc         *dev;
 811         unsigned long           flags;
 812
 813         ep = container_of(_ep, struct goku_ep, ep);
 814         if (!_ep || !_req || (!ep->ep.desc && ep->num != 0))
 815                 return -EINVAL;
 816         dev = ep->dev;
 817         if (!dev->driver)
 818                 return -ESHUTDOWN;
 819
 820         /* we can't touch (dma) registers when suspended */
 821         if (dev->ep0state == EP0_SUSPEND)
 822                 return -EBUSY;
 823
 824         VDBG(dev, "%s %s %s %s %p\n", __func__, _ep->name,
 825                 ep->is_in ? "IN" : "OUT",
 826                 ep->dma ? "dma" : "pio",
 827                 _req);
 828
 829         spin_lock_irqsave(&dev->lock, flags);
 830
 831         /* make sure it's actually queued on this endpoint */
 832         list_for_each_entry (req, &ep->queue, queue) {
 833                 if (&req->req == _req)
 834                         break;
 835         }
 836         if (&req->req != _req) {
 837                 spin_unlock_irqrestore (&dev->lock, flags);
 838                 return -EINVAL;
 839         }
 840
 841         if (ep->dma && ep->queue.next == &req->queue && !ep->stopped) {
 842                 abort_dma(ep, -ECONNRESET);
 843                 done(ep, req, -ECONNRESET);
 844                 dma_advance(dev, ep);
 845         } else if (!list_empty(&req->queue))
 846                 done(ep, req, -ECONNRESET);
 847         else
 848                 req = NULL;
 849         spin_unlock_irqrestore(&dev->lock, flags);
 850
 851         return req ? 0 : -EOPNOTSUPP;
 852 }
 853
 854 /*-------------------------------------------------------------------------*/
 855
 856 static void goku_clear_halt(struct goku_ep *ep)
 857 {
 858         // assert (ep->num !=0)
 859         VDBG(ep->dev, "%s clear halt\n", ep->ep.name);
 860         command(ep->dev->regs, COMMAND_SETDATA0, ep->num);
 861         command(ep->dev->regs, COMMAND_STALL_CLEAR, ep->num);
 862         if (ep->stopped) {
 863                 ep->stopped = 0;
 864                 if (ep->dma) {
 865                         struct goku_request     *req;
 866
 867                         if (list_empty(&ep->queue))
 868                                 return;
 869                         req = list_entry(ep->queue.next, struct goku_request,
 870                                                 queue);
 871                         (void) start_dma(ep, req);
 872                 } else
 873                         pio_advance(ep);
 874         }
 875 }
 876
 877 static int goku_set_halt(struct usb_ep *_ep, int value)
 878 {
 879         struct goku_ep  *ep;
 880         unsigned long   flags;
 881         int             retval = 0;
 882
 883         if (!_ep)
 884                 return -ENODEV;
 885         ep = container_of (_ep, struct goku_ep, ep);
 886
 887         if (ep->num == 0) {
 888                 if (value) {
 889                         ep->dev->ep0state = EP0_STALL;
 890                         ep->dev->ep[0].stopped = 1;
 891                 } else
 892                         return -EINVAL;
 893
 894         /* don't change EPxSTATUS_EP_INVALID to READY */
 895         } else if (!ep->ep.desc) {
 896                 DBG(ep->dev, "%s %s inactive?\n", __func__, ep->ep.name);
 897                 return -EINVAL;
 898         }
 899
 900         spin_lock_irqsave(&ep->dev->lock, flags);
 901         if (!list_empty(&ep->queue))
 902                 retval = -EAGAIN;
 903         else if (ep->is_in && value
 904                         /* data in (either) packet buffer? */
 905                         && (readl(&ep->dev->regs->DataSet)
 906                                         & DATASET_AB(ep->num)))
 907                 retval = -EAGAIN;
 908         else if (!value)
 909                 goku_clear_halt(ep);
 910         else {
 911                 ep->stopped = 1;
 912                 VDBG(ep->dev, "%s set halt\n", ep->ep.name);
 913                 command(ep->dev->regs, COMMAND_STALL, ep->num);
 914                 readl(ep->reg_status);
 915         }
 916         spin_unlock_irqrestore(&ep->dev->lock, flags);
 917         return retval;
 918 }
 919
 920 static int goku_fifo_status(struct usb_ep *_ep)
 921 {
 922         struct goku_ep                  *ep;
 923         struct goku_udc_regs __iomem    *regs;
 924         u32                             size;
 925
 926         if (!_ep)
 927                 return -ENODEV;
 928         ep = container_of(_ep, struct goku_ep, ep);
 929
 930         /* size is only reported sanely for OUT */
 931         if (ep->is_in)
 932                 return -EOPNOTSUPP;
 933
 934         /* ignores 16-byte dma buffer; SizeH == 0 */
 935         regs = ep->dev->regs;
 936         size = readl(&regs->EPxSizeLA[ep->num]) & DATASIZE;
 937         size += readl(&regs->EPxSizeLB[ep->num]) & DATASIZE;
 938         VDBG(ep->dev, "%s %s %u\n", __func__, ep->ep.name, size);
 939         return size;
 940 }
 941
 942 static void goku_fifo_flush(struct usb_ep *_ep)
 943 {
 944         struct goku_ep                  *ep;
 945         struct goku_udc_regs __iomem    *regs;
 946         u32                             size;
 947
 948         if (!_ep)
 949                 return;
 950         ep = container_of(_ep, struct goku_ep, ep);
 951         VDBG(ep->dev, "%s %s\n", __func__, ep->ep.name);
 952
 953         /* don't change EPxSTATUS_EP_INVALID to READY */
 954         if (!ep->ep.desc && ep->num != 0) {
 955                 DBG(ep->dev, "%s %s inactive?\n", __func__, ep->ep.name);
 956                 return;
 957         }
 958
 959         regs = ep->dev->regs;
 960         size = readl(&regs->EPxSizeLA[ep->num]);
 961         size &= DATASIZE;
 962
 963         /* Non-desirable behavior:  FIFO_CLEAR also clears the
 964          * endpoint halt feature.  For OUT, we _could_ just read
 965          * the bytes out (PIO, if !ep->dma); for in, no choice.
 966          */
 967         if (size)
 968                 command(regs, COMMAND_FIFO_CLEAR, ep->num);
 969 }
 970
 971 static struct usb_ep_ops goku_ep_ops = {
 972         .enable         = goku_ep_enable,
 973         .disable        = goku_ep_disable,
 974
 975         .alloc_request  = goku_alloc_request,
 976         .free_request   = goku_free_request,
 977
 978         .queue          = goku_queue,
 979         .dequeue        = goku_dequeue,
 980
 981         .set_halt       = goku_set_halt,
 982         .fifo_status    = goku_fifo_status,
 983         .fifo_flush     = goku_fifo_flush,
 984 };
 985
 986 /*-------------------------------------------------------------------------*/
 987
 988 static int goku_get_frame(struct usb_gadget *_gadget)
 989 {
 990         return -EOPNOTSUPP;
 991 }
 992
 993 static struct usb_ep *goku_match_ep(struct usb_gadget *g,
 994                 struct usb_endpoint_descriptor *desc,
 995                 struct usb_ss_ep_comp_descriptor *ep_comp)
 996 {
 997         struct goku_udc *dev = to_goku_udc(g);
 998         struct usb_ep *ep;
 999
1000         switch (usb_endpoint_type(desc)) {
1001         case USB_ENDPOINT_XFER_INT:
1002                 /* single buffering is enough */
1003                 ep = &dev->ep[3].ep;
1004                 if (usb_gadget_ep_match_desc(g, ep, desc, ep_comp))
1005                         return ep;
1006                 break;
1007         case USB_ENDPOINT_XFER_BULK:
1008                 if (usb_endpoint_dir_in(desc)) {
1009                         /* DMA may be available */
1010                         ep = &dev->ep[2].ep;
1011                         if (usb_gadget_ep_match_desc(g, ep, desc, ep_comp))
1012                                 return ep;
1013                 }
1014                 break;
1015         default:
1016                 /* nothing */ ;
1017         }
1018
1019         return NULL;
1020 }
1021
1022 static int goku_udc_start(struct usb_gadget *g,
1023                 struct usb_gadget_driver *driver);
1024 static int goku_udc_stop(struct usb_gadget *g);
1025
1026 static const struct usb_gadget_ops goku_ops = {
1027         .get_frame      = goku_get_frame,
1028         .udc_start      = goku_udc_start,
1029         .udc_stop       = goku_udc_stop,
1030         .match_ep       = goku_match_ep,
1031         // no remote wakeup
1032         // not selfpowered
1033 };
1034
1035 /*-------------------------------------------------------------------------*/
1036
1037 static inline const char *dmastr(void)
1038 {
1039         if (use_dma == 0)
1040                 return "(dma disabled)";
1041         else if (use_dma == 2)
1042                 return "(dma IN and OUT)";
1043         else
1044                 return "(dma IN)";
1045 }
1046
1047 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1048
1049 static const char proc_node_name [] = "driver/udc";
1050
1051 #define FOURBITS "%s%s%s%s"
1052 #define EIGHTBITS FOURBITS FOURBITS
1053
1054 static void dump_intmask(struct seq_file *m, const char *label, u32 mask)
1055 {
1056         /* int_status is the same format ... */
1057         seq_printf(m, "%s %05X =" FOURBITS EIGHTBITS EIGHTBITS "\n",
1058                    label, mask,
1059                    (mask & INT_PWRDETECT) ? " power" : "",
1060                    (mask & INT_SYSERROR) ? " sys" : "",
1061                    (mask & INT_MSTRDEND) ? " in-dma" : "",
1062                    (mask & INT_MSTWRTMOUT) ? " wrtmo" : "",
1063
1064                    (mask & INT_MSTWREND) ? " out-dma" : "",
1065                    (mask & INT_MSTWRSET) ? " wrset" : "",
1066                    (mask & INT_ERR) ? " err" : "",
1067                    (mask & INT_SOF) ? " sof" : "",
1068
1069                    (mask & INT_EP3NAK) ? " ep3nak" : "",
1070                    (mask & INT_EP2NAK) ? " ep2nak" : "",
1071                    (mask & INT_EP1NAK) ? " ep1nak" : "",
1072                    (mask & INT_EP3DATASET) ? " ep3" : "",
1073
1074                    (mask & INT_EP2DATASET) ? " ep2" : "",
1075                    (mask & INT_EP1DATASET) ? " ep1" : "",
1076                    (mask & INT_STATUSNAK) ? " ep0snak" : "",
1077                    (mask & INT_STATUS) ? " ep0status" : "",
1078
1079                    (mask & INT_SETUP) ? " setup" : "",
1080                    (mask & INT_ENDPOINT0) ? " ep0" : "",
1081                    (mask & INT_USBRESET) ? " reset" : "",
1082                    (mask & INT_SUSPEND) ? " suspend" : "");
1083 }
1084
1085 static const char *udc_ep_state(enum ep0state state)
1086 {
1087         switch (state) {
1088         case EP0_DISCONNECT:
1089                 return "ep0_disconnect";
1090         case EP0_IDLE:
1091                 return "ep0_idle";
1092         case EP0_IN:
1093                 return "ep0_in";
1094         case EP0_OUT:
1095                 return "ep0_out";
1096         case EP0_STATUS:
1097                 return "ep0_status";
1098         case EP0_STALL:
1099                 return "ep0_stall";
1100         case EP0_SUSPEND:
1101                 return "ep0_suspend";
1102         }
1103
1104         return "ep0_?";
1105 }
1106
1107 static const char *udc_ep_status(u32 status)
1108 {
1109         switch (status & EPxSTATUS_EP_MASK) {
1110         case EPxSTATUS_EP_READY:
1111                 return "ready";
1112         case EPxSTATUS_EP_DATAIN:
1113                 return "packet";
1114         case EPxSTATUS_EP_FULL:
1115                 return "full";
1116         case EPxSTATUS_EP_TX_ERR:       /* host will retry */
1117                 return "tx_err";
1118         case EPxSTATUS_EP_RX_ERR:
1119                 return "rx_err";
1120         case EPxSTATUS_EP_BUSY:         /* ep0 only */
1121                 return "busy";
1122         case EPxSTATUS_EP_STALL:
1123                 return "stall";
1124         case EPxSTATUS_EP_INVALID:      /* these "can't happen" */
1125                 return "invalid";
1126         }
1127
1128         return "?";
1129 }
1130
1131 static int udc_proc_read(struct seq_file *m, void *v)
1132 {
1133         struct goku_udc                 *dev = m->private;
1134         struct goku_udc_regs __iomem    *regs = dev->regs;
1135         unsigned long                   flags;
1136         int                             i, is_usb_connected;
1137         u32                             tmp;
1138
1139         local_irq_save(flags);
1140
1141         /* basic device status */
1142         tmp = readl(&regs->power_detect);
1143         is_usb_connected = tmp & PW_DETECT;
1144         seq_printf(m,
1145                    "%s - %s\n"
1146                    "%s version: %s %s\n"
1147                    "Gadget driver: %s\n"
1148                    "Host %s, %s\n"
1149                    "\n",
1150                    pci_name(dev->pdev), driver_desc,
1151                    driver_name, DRIVER_VERSION, dmastr(),
1152                    dev->driver ? dev->driver->driver.name : "(none)",
1153                    is_usb_connected
1154                            ? ((tmp & PW_PULLUP) ? "full speed" : "powered")
1155                            : "disconnected",
1156                    udc_ep_state(dev->ep0state));
1157
1158         dump_intmask(m, "int_status", readl(&regs->int_status));
1159         dump_intmask(m, "int_enable", readl(&regs->int_enable));
1160
1161         if (!is_usb_connected || !dev->driver || (tmp & PW_PULLUP) == 0)
1162                 goto done;
1163
1164         /* registers for (active) device and ep0 */
1165         seq_printf(m, "\nirqs %lu\ndataset %02x single.bcs %02x.%02x state %x addr %u\n",
1166                    dev->irqs, readl(&regs->DataSet),
1167                    readl(&regs->EPxSingle), readl(&regs->EPxBCS),
1168                    readl(&regs->UsbState),
1169                    readl(&regs->address));
1170         if (seq_has_overflowed(m))
1171                 goto done;
1172
1173         tmp = readl(&regs->dma_master);
1174         seq_printf(m, "dma %03X =" EIGHTBITS "%s %s\n",
1175                    tmp,
1176                    (tmp & MST_EOPB_DIS) ? " eopb-" : "",
1177                    (tmp & MST_EOPB_ENA) ? " eopb+" : "",
1178                    (tmp & MST_TIMEOUT_DIS) ? " tmo-" : "",
1179                    (tmp & MST_TIMEOUT_ENA) ? " tmo+" : "",
1180
1181                    (tmp & MST_RD_EOPB) ? " eopb" : "",
1182                    (tmp & MST_RD_RESET) ? " in_reset" : "",
1183                    (tmp & MST_WR_RESET) ? " out_reset" : "",
1184                    (tmp & MST_RD_ENA) ? " IN" : "",
1185
1186                    (tmp & MST_WR_ENA) ? " OUT" : "",
1187                    (tmp & MST_CONNECTION) ? "ep1in/ep2out" : "ep1out/ep2in");
1188         if (seq_has_overflowed(m))
1189                 goto done;
1190
1191         /* dump endpoint queues */
1192         for (i = 0; i < 4; i++) {
1193                 struct goku_ep          *ep = &dev->ep [i];
1194                 struct goku_request     *req;
1195
1196                 if (i && !ep->ep.desc)
1197                         continue;
1198
1199                 tmp = readl(ep->reg_status);
1200                 seq_printf(m, "%s %s max %u %s, irqs %lu, status %02x (%s) " FOURBITS "\n",
1201                            ep->ep.name,
1202                            ep->is_in ? "in" : "out",
1203                            ep->ep.maxpacket,
1204                            ep->dma ? "dma" : "pio",
1205                            ep->irqs,
1206                            tmp, udc_ep_status(tmp),
1207                            (tmp & EPxSTATUS_TOGGLE) ? "data1" : "data0",
1208                            (tmp & EPxSTATUS_SUSPEND) ? " suspend" : "",
1209                            (tmp & EPxSTATUS_FIFO_DISABLE) ? " disable" : "",
1210                            (tmp & EPxSTATUS_STAGE_ERROR) ? " ep0stat" : "");
1211                 if (seq_has_overflowed(m))
1212                         goto done;
1213
1214                 if (list_empty(&ep->queue)) {
1215                         seq_puts(m, "\t(nothing queued)\n");
1216                         if (seq_has_overflowed(m))
1217                                 goto done;
1218                         continue;
1219                 }
1220                 list_for_each_entry(req, &ep->queue, queue) {
1221                         if (ep->dma && req->queue.prev == &ep->queue) {
1222                                 if (i == UDC_MSTRD_ENDPOINT)
1223                                         tmp = readl(&regs->in_dma_current);
1224                                 else
1225                                         tmp = readl(&regs->out_dma_current);
1226                                 tmp -= req->req.dma;
1227                                 tmp++;
1228                         } else
1229                                 tmp = req->req.actual;
1230
1231                         seq_printf(m, "\treq %p len %u/%u buf %p\n",
1232                                    &req->req, tmp, req->req.length,
1233                                    req->req.buf);
1234                         if (seq_has_overflowed(m))
1235                                 goto done;
1236                 }
1237         }
1238
1239 done:
1240         local_irq_restore(flags);
1241         return 0;
1242 }
1243
1244 /*
1245  * seq_file wrappers for procfile show routines.
1246  */
1247 static int udc_proc_open(struct inode *inode, struct file *file)
1248 {
1249         return single_open(file, udc_proc_read, PDE_DATA(file_inode(file)));
1250 }
1251
1252 static const struct file_operations udc_proc_fops = {
1253         .open           = udc_proc_open,
1254         .read           = seq_read,
1255         .llseek         = seq_lseek,
1256         .release        = single_release,
1257 };
1258
1259 #endif  /* CONFIG_USB_GADGET_DEBUG_FILES */
1260
1261 /*-------------------------------------------------------------------------*/
1262
1263 static void udc_reinit (struct goku_udc *dev)
1264 {
1265         static char *names [] = { "ep0", "ep1-bulk", "ep2-bulk", "ep3-bulk" };
1266
1267         unsigned i;
1268
1269         INIT_LIST_HEAD (&dev->gadget.ep_list);
1270         dev->gadget.ep0 = &dev->ep [0].ep;
1271         dev->gadget.speed = USB_SPEED_UNKNOWN;
1272         dev->ep0state = EP0_DISCONNECT;
1273         dev->irqs = 0;
1274
1275         for (i = 0; i < 4; i++) {
1276                 struct goku_ep  *ep = &dev->ep[i];
1277
1278                 ep->num = i;
1279                 ep->ep.name = names[i];
1280                 ep->reg_fifo = &dev->regs->ep_fifo [i];
1281                 ep->reg_status = &dev->regs->ep_status [i];
1282                 ep->reg_mode = &dev->regs->ep_mode[i];
1283
1284                 ep->ep.ops = &goku_ep_ops;
1285                 list_add_tail (&ep->ep.ep_list, &dev->gadget.ep_list);
1286                 ep->dev = dev;
1287                 INIT_LIST_HEAD (&ep->queue);
1288
1289                 ep_reset(NULL, ep);
1290
1291                 if (i == 0)
1292                         ep->ep.caps.type_control = true;
1293                 else
1294                         ep->ep.caps.type_bulk = true;
1295
1296                 ep->ep.caps.dir_in = true;
1297                 ep->ep.caps.dir_out = true;
1298         }
1299
1300         dev->ep[0].reg_mode = NULL;
1301         usb_ep_set_maxpacket_limit(&dev->ep[0].ep, MAX_EP0_SIZE);
1302         list_del_init (&dev->ep[0].ep.ep_list);
1303 }
1304
1305 static void udc_reset(struct goku_udc *dev)
1306 {
1307         struct goku_udc_regs __iomem    *regs = dev->regs;
1308
1309         writel(0, &regs->power_detect);
1310         writel(0, &regs->int_enable);
1311         readl(&regs->int_enable);
1312         dev->int_enable = 0;
1313
1314         /* deassert reset, leave USB D+ at hi-Z (no pullup)
1315          * don't let INT_PWRDETECT sequence begin
1316          */
1317         udelay(250);
1318         writel(PW_RESETB, &regs->power_detect);
1319         readl(&regs->int_enable);
1320 }
1321
1322 static void ep0_start(struct goku_udc *dev)
1323 {
1324         struct goku_udc_regs __iomem    *regs = dev->regs;
1325         unsigned                        i;
1326
1327         VDBG(dev, "%s\n", __func__);
1328
1329         udc_reset(dev);
1330         udc_reinit (dev);
1331         //writel(MST_EOPB_ENA | MST_TIMEOUT_ENA, &regs->dma_master);
1332
1333         /* hw handles set_address, set_feature, get_status; maybe more */
1334         writel(   G_REQMODE_SET_INTF | G_REQMODE_GET_INTF
1335                 | G_REQMODE_SET_CONF | G_REQMODE_GET_CONF
1336                 | G_REQMODE_GET_DESC
1337                 | G_REQMODE_CLEAR_FEAT
1338                 , &regs->reqmode);
1339
1340         for (i = 0; i < 4; i++)
1341                 dev->ep[i].irqs = 0;
1342
1343         /* can't modify descriptors after writing UsbReady */
1344         for (i = 0; i < DESC_LEN; i++)
1345                 writel(0, &regs->descriptors[i]);
1346         writel(0, &regs->UsbReady);
1347
1348         /* expect ep0 requests when the host drops reset */
1349         writel(PW_RESETB | PW_PULLUP, &regs->power_detect);
1350         dev->int_enable = INT_DEVWIDE | INT_EP0;
1351         writel(dev->int_enable, &dev->regs->int_enable);
1352         readl(&regs->int_enable);
1353         dev->gadget.speed = USB_SPEED_FULL;
1354         dev->ep0state = EP0_IDLE;
1355 }
1356
1357 static void udc_enable(struct goku_udc *dev)
1358 {
1359         /* start enumeration now, or after power detect irq */
1360         if (readl(&dev->regs->power_detect) & PW_DETECT)
1361                 ep0_start(dev);
1362         else {
1363                 DBG(dev, "%s\n", __func__);
1364                 dev->int_enable = INT_PWRDETECT;
1365                 writel(dev->int_enable, &dev->regs->int_enable);
1366         }
1367 }
1368
1369 /*-------------------------------------------------------------------------*/
1370
1371 /* keeping it simple:
1372  * - one bus driver, initted first;
1373  * - one function driver, initted second
1374  */
1375
1376 /* when a driver is successfully registered, it will receive
1377  * control requests including set_configuration(), which enables
1378  * non-control requests.  then usb traffic follows until a
1379  * disconnect is reported.  then a host may connect again, or
1380  * the driver might get unbound.
1381  */
1382 static int goku_udc_start(struct usb_gadget *g,
1383                 struct usb_gadget_driver *driver)
1384 {
1385         struct goku_udc *dev = to_goku_udc(g);
1386
1387         /* hook up the driver */
1388         driver->driver.bus = NULL;
1389         dev->driver = driver;
1390
1391         /*
1392          * then enable host detection and ep0; and we're ready
1393          * for set_configuration as well as eventual disconnect.
1394          */
1395         udc_enable(dev);
1396
1397         return 0;
1398 }
1399
1400 static void stop_activity(struct goku_udc *dev)
1401 {
1402         unsigned        i;
1403
1404         DBG (dev, "%s\n", __func__);
1405
1406         /* disconnect gadget driver after quiesceing hw and the driver */
1407         udc_reset (dev);
1408         for (i = 0; i < 4; i++)
1409                 nuke(&dev->ep [i], -ESHUTDOWN);
1410
1411         if (dev->driver)
1412                 udc_enable(dev);
1413 }
1414
1415 static int goku_udc_stop(struct usb_gadget *g)
1416 {
1417         struct goku_udc *dev = to_goku_udc(g);
1418         unsigned long   flags;
1419
1420         spin_lock_irqsave(&dev->lock, flags);
1421         dev->driver = NULL;
1422         stop_activity(dev);
1423         spin_unlock_irqrestore(&dev->lock, flags);
1424
1425         return 0;
1426 }
1427
1428 /*-------------------------------------------------------------------------*/
1429
1430 static void ep0_setup(struct goku_udc *dev)
1431 {
1432         struct goku_udc_regs __iomem    *regs = dev->regs;
1433         struct usb_ctrlrequest          ctrl;
1434         int                             tmp;
1435
1436         /* read SETUP packet and enter DATA stage */
1437         ctrl.bRequestType = readl(&regs->bRequestType);
1438         ctrl.bRequest = readl(&regs->bRequest);
1439         ctrl.wValue  = cpu_to_le16((readl(&regs->wValueH)  << 8)
1440                                         | readl(&regs->wValueL));
1441         ctrl.wIndex  = cpu_to_le16((readl(&regs->wIndexH)  << 8)
1442                                         | readl(&regs->wIndexL));
1443         ctrl.wLength = cpu_to_le16((readl(&regs->wLengthH) << 8)
1444                                         | readl(&regs->wLengthL));
1445         writel(0, &regs->SetupRecv);
1446
1447         nuke(&dev->ep[0], 0);
1448         dev->ep[0].stopped = 0;
1449         if (likely(ctrl.bRequestType & USB_DIR_IN)) {
1450                 dev->ep[0].is_in = 1;
1451                 dev->ep0state = EP0_IN;
1452                 /* detect early status stages */
1453                 writel(ICONTROL_STATUSNAK, &dev->regs->IntControl);
1454         } else {
1455                 dev->ep[0].is_in = 0;
1456                 dev->ep0state = EP0_OUT;
1457
1458                 /* NOTE:  CLEAR_FEATURE is done in software so that we can
1459                  * synchronize transfer restarts after bulk IN stalls.  data
1460                  * won't even enter the fifo until the halt is cleared.
1461                  */
1462                 switch (ctrl.bRequest) {
1463                 case USB_REQ_CLEAR_FEATURE:
1464                         switch (ctrl.bRequestType) {
1465                         case USB_RECIP_ENDPOINT:
1466                                 tmp = le16_to_cpu(ctrl.wIndex) & 0x0f;
1467                                 /* active endpoint */
1468                                 if (tmp > 3 ||
1469                                     (!dev->ep[tmp].ep.desc && tmp != 0))
1470                                         goto stall;
1471                                 if (ctrl.wIndex & cpu_to_le16(
1472                                                 USB_DIR_IN)) {
1473                                         if (!dev->ep[tmp].is_in)
1474                                                 goto stall;
1475                                 } else {
1476                                         if (dev->ep[tmp].is_in)
1477                                                 goto stall;
1478                                 }
1479                                 if (ctrl.wValue != cpu_to_le16(
1480                                                 USB_ENDPOINT_HALT))
1481                                         goto stall;
1482                                 if (tmp)
1483                                         goku_clear_halt(&dev->ep[tmp]);
1484 succeed:
1485                                 /* start ep0out status stage */
1486                                 writel(~(1<<0), &regs->EOP);
1487                                 dev->ep[0].stopped = 1;
1488                                 dev->ep0state = EP0_STATUS;
1489                                 return;
1490                         case USB_RECIP_DEVICE:
1491                                 /* device remote wakeup: always clear */
1492                                 if (ctrl.wValue != cpu_to_le16(1))
1493                                         goto stall;
1494                                 VDBG(dev, "clear dev remote wakeup\n");
1495                                 goto succeed;
1496                         case USB_RECIP_INTERFACE:
1497                                 goto stall;
1498                         default:                /* pass to gadget driver */
1499                                 break;
1500                         }
1501                         break;
1502                 default:
1503                         break;
1504                 }
1505         }
1506
1507 #ifdef USB_TRACE
1508         VDBG(dev, "SETUP %02x.%02x v%04x i%04x l%04x\n",
1509                 ctrl.bRequestType, ctrl.bRequest,
1510                 le16_to_cpu(ctrl.wValue), le16_to_cpu(ctrl.wIndex),
1511                 le16_to_cpu(ctrl.wLength));
1512 #endif
1513
1514         /* hw wants to know when we're configured (or not) */
1515         dev->req_config = (ctrl.bRequest == USB_REQ_SET_CONFIGURATION
1516                                 && ctrl.bRequestType == USB_RECIP_DEVICE);
1517         if (unlikely(dev->req_config))
1518                 dev->configured = (ctrl.wValue != cpu_to_le16(0));
1519
1520         /* delegate everything to the gadget driver.
1521          * it may respond after this irq handler returns.
1522          */
1523         spin_unlock (&dev->lock);
1524         tmp = dev->driver->setup(&dev->gadget, &ctrl);
1525         spin_lock (&dev->lock);
1526         if (unlikely(tmp < 0)) {
1527 stall:
1528 #ifdef USB_TRACE
1529                 VDBG(dev, "req %02x.%02x protocol STALL; err %d\n",
1530                                 ctrl.bRequestType, ctrl.bRequest, tmp);
1531 #endif
1532                 command(regs, COMMAND_STALL, 0);
1533                 dev->ep[0].stopped = 1;
1534                 dev->ep0state = EP0_STALL;
1535         }
1536
1537         /* expect at least one data or status stage irq */
1538 }
1539
1540 #define ACK(irqbit) { \
1541                 stat &= ~irqbit; \
1542                 writel(~irqbit, &regs->int_status); \
1543                 handled = 1; \
1544                 }
1545
1546 static irqreturn_t goku_irq(int irq, void *_dev)
1547 {
1548         struct goku_udc                 *dev = _dev;
1549         struct goku_udc_regs __iomem    *regs = dev->regs;
1550         struct goku_ep                  *ep;
1551         u32                             stat, handled = 0;
1552         unsigned                        i, rescans = 5;
1553
1554         spin_lock(&dev->lock);
1555
1556 rescan:
1557         stat = readl(&regs->int_status) & dev->int_enable;
1558         if (!stat)
1559                 goto done;
1560         dev->irqs++;
1561
1562         /* device-wide irqs */
1563         if (unlikely(stat & INT_DEVWIDE)) {
1564                 if (stat & INT_SYSERROR) {
1565                         ERROR(dev, "system error\n");
1566                         stop_activity(dev);
1567                         stat = 0;
1568                         handled = 1;
1569                         // FIXME have a neater way to prevent re-enumeration
1570                         dev->driver = NULL;
1571                         goto done;
1572                 }
1573                 if (stat & INT_PWRDETECT) {
1574                         writel(~stat, &regs->int_status);
1575                         if (readl(&dev->regs->power_detect) & PW_DETECT) {
1576                                 VDBG(dev, "connect\n");
1577                                 ep0_start(dev);
1578                         } else {
1579                                 DBG(dev, "disconnect\n");
1580                                 if (dev->gadget.speed == USB_SPEED_FULL)
1581                                         stop_activity(dev);
1582                                 dev->ep0state = EP0_DISCONNECT;
1583                                 dev->int_enable = INT_DEVWIDE;
1584                                 writel(dev->int_enable, &dev->regs->int_enable);
1585                         }
1586                         stat = 0;
1587                         handled = 1;
1588                         goto done;
1589                 }
1590                 if (stat & INT_SUSPEND) {
1591                         ACK(INT_SUSPEND);
1592                         if (readl(&regs->ep_status[0]) & EPxSTATUS_SUSPEND) {
1593                                 switch (dev->ep0state) {
1594                                 case EP0_DISCONNECT:
1595                                 case EP0_SUSPEND:
1596                                         goto pm_next;
1597                                 default:
1598                                         break;
1599                                 }
1600                                 DBG(dev, "USB suspend\n");
1601                                 dev->ep0state = EP0_SUSPEND;
1602                                 if (dev->gadget.speed != USB_SPEED_UNKNOWN
1603                                                 && dev->driver
1604                                                 && dev->driver->suspend) {
1605                                         spin_unlock(&dev->lock);
1606                                         dev->driver->suspend(&dev->gadget);
1607                                         spin_lock(&dev->lock);
1608                                 }
1609                         } else {
1610                                 if (dev->ep0state != EP0_SUSPEND) {
1611                                         DBG(dev, "bogus USB resume %d\n",
1612                                                 dev->ep0state);
1613                                         goto pm_next;
1614                                 }
1615                                 DBG(dev, "USB resume\n");
1616                                 dev->ep0state = EP0_IDLE;
1617                                 if (dev->gadget.speed != USB_SPEED_UNKNOWN
1618                                                 && dev->driver
1619                                                 && dev->driver->resume) {
1620                                         spin_unlock(&dev->lock);
1621                                         dev->driver->resume(&dev->gadget);
1622                                         spin_lock(&dev->lock);
1623                                 }
1624                         }
1625                 }
1626 pm_next:
1627                 if (stat & INT_USBRESET) {              /* hub reset done */
1628                         ACK(INT_USBRESET);
1629                         INFO(dev, "USB reset done, gadget %s\n",
1630                                 dev->driver->driver.name);
1631                 }
1632                 // and INT_ERR on some endpoint's crc/bitstuff/... problem
1633         }
1634
1635         /* progress ep0 setup, data, or status stages.
1636          * no transition {EP0_STATUS, EP0_STALL} --> EP0_IDLE; saves irqs
1637          */
1638         if (stat & INT_SETUP) {
1639                 ACK(INT_SETUP);
1640                 dev->ep[0].irqs++;
1641                 ep0_setup(dev);
1642         }
1643         if (stat & INT_STATUSNAK) {
1644                 ACK(INT_STATUSNAK|INT_ENDPOINT0);
1645                 if (dev->ep0state == EP0_IN) {
1646                         ep = &dev->ep[0];
1647                         ep->irqs++;
1648                         nuke(ep, 0);
1649                         writel(~(1<<0), &regs->EOP);
1650                         dev->ep0state = EP0_STATUS;
1651                 }
1652         }
1653         if (stat & INT_ENDPOINT0) {
1654                 ACK(INT_ENDPOINT0);
1655                 ep = &dev->ep[0];
1656                 ep->irqs++;
1657                 pio_advance(ep);
1658         }
1659
1660         /* dma completion */
1661         if (stat & INT_MSTRDEND) {      /* IN */
1662                 ACK(INT_MSTRDEND);
1663                 ep = &dev->ep[UDC_MSTRD_ENDPOINT];
1664                 ep->irqs++;
1665                 dma_advance(dev, ep);
1666         }
1667         if (stat & INT_MSTWREND) {      /* OUT */
1668                 ACK(INT_MSTWREND);
1669                 ep = &dev->ep[UDC_MSTWR_ENDPOINT];
1670                 ep->irqs++;
1671                 dma_advance(dev, ep);
1672         }
1673         if (stat & INT_MSTWRTMOUT) {    /* OUT */
1674                 ACK(INT_MSTWRTMOUT);
1675                 ep = &dev->ep[UDC_MSTWR_ENDPOINT];
1676                 ep->irqs++;
1677                 ERROR(dev, "%s write timeout ?\n", ep->ep.name);
1678                 // reset dma? then dma_advance()
1679         }
1680
1681         /* pio */
1682         for (i = 1; i < 4; i++) {
1683                 u32             tmp = INT_EPxDATASET(i);
1684
1685                 if (!(stat & tmp))
1686                         continue;
1687                 ep = &dev->ep[i];
1688                 pio_advance(ep);
1689                 if (list_empty (&ep->queue))
1690                         pio_irq_disable(dev, regs, i);
1691                 stat &= ~tmp;
1692                 handled = 1;
1693                 ep->irqs++;
1694         }
1695
1696         if (rescans--)
1697                 goto rescan;
1698
1699 done:
1700         (void)readl(&regs->int_enable);
1701         spin_unlock(&dev->lock);
1702         if (stat)
1703                 DBG(dev, "unhandled irq status: %05x (%05x, %05x)\n", stat,
1704                                 readl(&regs->int_status), dev->int_enable);
1705         return IRQ_RETVAL(handled);
1706 }
1707
1708 #undef ACK
1709
1710 /*-------------------------------------------------------------------------*/
1711
1712 static void gadget_release(struct device *_dev)
1713 {
1714         struct goku_udc *dev = dev_get_drvdata(_dev);
1715
1716         kfree(dev);
1717 }
1718
1719 /* tear down the binding between this driver and the pci device */
1720
1721 static void goku_remove(struct pci_dev *pdev)
1722 {
1723         struct goku_udc         *dev = pci_get_drvdata(pdev);
1724
1725         DBG(dev, "%s\n", __func__);
1726
1727         usb_del_gadget_udc(&dev->gadget);
1728
1729         BUG_ON(dev->driver);
1730
1731 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1732         remove_proc_entry(proc_node_name, NULL);
1733 #endif
1734         if (dev->regs)
1735                 udc_reset(dev);
1736         if (dev->got_irq)
1737                 free_irq(pdev->irq, dev);
1738         if (dev->regs)
1739                 iounmap(dev->regs);
1740         if (dev->got_region)
1741                 release_mem_region(pci_resource_start (pdev, 0),
1742                                 pci_resource_len (pdev, 0));
1743         if (dev->enabled)
1744                 pci_disable_device(pdev);
1745
1746         dev->regs = NULL;
1747
1748         INFO(dev, "unbind\n");
1749 }
1750
1751 /* wrap this driver around the specified pci device, but
1752  * don't respond over USB until a gadget driver binds to us.
1753  */
1754
1755 static int goku_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1756 {
1757         struct goku_udc         *dev = NULL;
1758         unsigned long           resource, len;
1759         void __iomem            *base = NULL;
1760         int                     retval;
1761
1762         if (!pdev->irq) {
1763                 printk(KERN_ERR "Check PCI %s IRQ setup!\n", pci_name(pdev));
1764                 retval = -ENODEV;
1765                 goto err;
1766         }
1767
1768         /* alloc, and start init */
1769         dev = kzalloc (sizeof *dev, GFP_KERNEL);
1770         if (!dev) {
1771                 retval = -ENOMEM;
1772                 goto err;
1773         }
1774
1775         spin_lock_init(&dev->lock);
1776         dev->pdev = pdev;
1777         dev->gadget.ops = &goku_ops;
1778         dev->gadget.max_speed = USB_SPEED_FULL;
1779
1780         /* the "gadget" abstracts/virtualizes the controller */
1781         dev->gadget.name = driver_name;
1782
1783         /* now all the pci goodies ... */
1784         retval = pci_enable_device(pdev);
1785         if (retval < 0) {
1786                 DBG(dev, "can't enable, %d\n", retval);
1787                 goto err;
1788         }
1789         dev->enabled = 1;
1790
1791         resource = pci_resource_start(pdev, 0);
1792         len = pci_resource_len(pdev, 0);
1793         if (!request_mem_region(resource, len, driver_name)) {
1794                 DBG(dev, "controller already in use\n");
1795                 retval = -EBUSY;
1796                 goto err;
1797         }
1798         dev->got_region = 1;
1799
1800         base = ioremap_nocache(resource, len);
1801         if (base == NULL) {
1802                 DBG(dev, "can't map memory\n");
1803                 retval = -EFAULT;
1804                 goto err;
1805         }
1806         dev->regs = (struct goku_udc_regs __iomem *) base;
1807
1808         pci_set_drvdata(pdev, dev);
1809         INFO(dev, "%s\n", driver_desc);
1810         INFO(dev, "version: " DRIVER_VERSION " %s\n", dmastr());
1811         INFO(dev, "irq %d, pci mem %p\n", pdev->irq, base);
1812
1813         /* init to known state, then setup irqs */
1814         udc_reset(dev);
1815         udc_reinit (dev);
1816         if (request_irq(pdev->irq, goku_irq, IRQF_SHARED,
1817                         driver_name, dev) != 0) {
1818                 DBG(dev, "request interrupt %d failed\n", pdev->irq);
1819                 retval = -EBUSY;
1820                 goto err;
1821         }
1822         dev->got_irq = 1;
1823         if (use_dma)
1824                 pci_set_master(pdev);
1825
1826
1827 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
1828         proc_create_data(proc_node_name, 0, NULL, &udc_proc_fops, dev);
1829 #endif
1830
1831         retval = usb_add_gadget_udc_release(&pdev->dev, &dev->gadget,
1832                         gadget_release);
1833         if (retval)
1834                 goto err;
1835
1836         return 0;
1837
1838 err:
1839         if (dev)
1840                 goku_remove (pdev);
1841         return retval;
1842 }
1843
1844
1845 /*-------------------------------------------------------------------------*/
1846
1847 static const struct pci_device_id pci_ids[] = { {
1848         .class =        PCI_CLASS_SERIAL_USB_DEVICE,
1849         .class_mask =   ~0,
1850         .vendor =       0x102f,         /* Toshiba */
1851         .device =       0x0107,         /* this UDC */
1852         .subvendor =    PCI_ANY_ID,
1853         .subdevice =    PCI_ANY_ID,
1854
1855 }, { /* end: all zeroes */ }
1856 };
1857 MODULE_DEVICE_TABLE (pci, pci_ids);
1858
1859 static struct pci_driver goku_pci_driver = {
1860         .name =         (char *) driver_name,
1861         .id_table =     pci_ids,
1862
1863         .probe =        goku_probe,
1864         .remove =       goku_remove,
1865
1866         /* FIXME add power management support */
1867 };
1868
1869 module_pci_driver(goku_pci_driver);