drivers/staging/ced1401/usb1401.c

   1 /***********************************************************************************
   2  CED1401 usb driver. This basic loading is based on the usb-skeleton.c code that is:
   3  Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
   4  Copyright (C) 2012 Alois Schloegl <alois.schloegl@ist.ac.at>
   5  There is not a great deal of the skeleton left.
   6
   7  All the remainder dealing specifically with the CED1401 is based on drivers written
   8  by CED for other systems (mainly Windows) and is:
   9  Copyright (C) 2010 Cambridge Electronic Design Ltd
  10  Author Greg P Smith (greg@ced.co.uk)
  11
  12  This program is free software; you can redistribute it and/or
  13  modify it under the terms of the GNU General Public License
  14  as published by the Free Software Foundation; either version 2
  15  of the License, or (at your option) any later version.
  16
  17  This program is distributed in the hope that it will be useful,
  18  but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  GNU General Public License for more details.
  21
  22  You should have received a copy of the GNU General Public License
  23  along with this program; if not, write to the Free Software
  24  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  25
  26 Endpoints
  27 *********
  28 There are 4 endpoints plus the control endpoint in the standard interface
  29 provided by most 1401s. The control endpoint is used for standard USB requests,
  30 plus various CED-specific transactions such as start self test, debug and get
  31 the 1401 status. The other endpoints are:
  32
  33  1 Characters to the 1401
  34  2 Characters from the 1401
  35  3 Block data to the 1401
  36  4 Block data to the host.
  37
  38 inside the driver these are indexed as an array from 0 to 3, transactions
  39 over the control endpoint are carried out using a separate mechanism. The
  40 use of the endpoints is mostly straightforward, with the driver issuing
  41 IO request packets (IRPs) as required to transfer data to and from the 1401.
  42 The handling of endpoint 2 is different because it is used for characters
  43 from the 1401, which can appear spontaneously and without any other driver
  44 activity - for example to repeatedly request DMA transfers in Spike2. The
  45 desired effect is achieved by using an interrupt endpoint which can be
  46 polled to see if it has data available, and writing the driver so that it
  47 always maintains a pending read IRP from that endpoint which will read the
  48 character data and terminate as soon as the 1401 makes data available. This
  49 works very well, some care is taken with when you kick off this character
  50 read IRP to avoid it being active when it is not wanted but generally it
  51 is running all the time.
  52
  53 In the 2270, there are only three endpoints plus the control endpoint. In
  54 addition to the transactions mentioned above, the control endpoint is used
  55 to transfer character data to the 1401. The other endpoints are used as:
  56
  57  1 Characters from the 1401
  58  2 Block data to the 1401
  59  3 Block data to the host.
  60
  61 The type of interface available is specified by the interface subclass field
  62 in the interface descriptor provided by the 1401. See the USB_INT_ constants
  63 for the values that this field can hold.
  64
  65 ****************************************************************************
  66 Linux implementation
  67
  68 Although Linux Device Drivers (3rd Edition) was a major source of information,
  69 it is very out of date. A lot of information was gleaned from the latest
  70 usb_skeleton.c code (you need to download the kernel sources to get this).
  71
  72 To match the Windows version, everything is done using ioctl calls. All the
  73 device state is held in the DEVICE_EXTENSION (named to match Windows use).
  74 Block transfers are done by using get_user_pages() to pin down a list of
  75 pages that we hold a pointer to in the device driver. We also allocate a
  76 coherent transfer buffer of size STAGED_SZ (this must be a multiple of the
  77 bulk endpoint size so that the 1401 does not realise that we break large
  78 transfers down into smaller pieces). We use kmap_atomic() to get a kernel
  79 va for each page, as it is required, for copying; see CopyUserSpace().
  80
  81 All character and data transfers are done using asynchronous IO. All Urbs are
  82 tracked by anchoring them. Status and debug ioctls are implemented with the
  83 synchronous non-Urb based transfers.
  84 */
  85
  86 #include <linux/kernel.h>
  87 #include <linux/errno.h>
  88 #include <linux/usb.h>
  89 #include <linux/mutex.h>
  90 #include <linux/mm.h>
  91 #include <linux/highmem.h>
  92 #include <linux/init.h>
  93 #include <linux/slab.h>
  94 #include <linux/module.h>
  95 #include <linux/kref.h>
  96 #include <linux/uaccess.h>
  97
  98 #include "usb1401.h"
  99
 100 /* Define these values to match your devices */
 101 #define USB_CED_VENDOR_ID       0x0525
 102 #define USB_CED_PRODUCT_ID      0xa0f0
 103
 104 /* table of devices that work with this driver */
 105 static const struct usb_device_id ced_table[] = {
 106         {USB_DEVICE(USB_CED_VENDOR_ID, USB_CED_PRODUCT_ID)},
 107         {}                      /* Terminating entry */
 108 };
 109
 110 MODULE_DEVICE_TABLE(usb, ced_table);
 111
 112 /* Get a minor range for your devices from the usb maintainer */
 113 #define USB_CED_MINOR_BASE      192
 114
 115 /* our private defines. if this grows any larger, use your own .h file */
 116 #define MAX_TRANSFER            (PAGE_SIZE - 512)
 117 /* MAX_TRANSFER is chosen so that the VM is not stressed by
 118    allocations > PAGE_SIZE and the number of packets in a page
 119    is an integer 512 is the largest possible packet on EHCI */
 120 #define WRITES_IN_FLIGHT        8
 121 /* arbitrarily chosen */
 122
 123 static struct usb_driver ced_driver;
 124
 125 static void ced_delete(struct kref *kref)
 126 {
 127         DEVICE_EXTENSION *pdx = to_DEVICE_EXTENSION(kref);
 128
 129         /*  Free up the output buffer, then free the output urb. Note that the interface member */
 130         /*  of pdx will probably be NULL, so cannot be used to get to dev. */
 131         usb_free_coherent(pdx->udev, OUTBUF_SZ, pdx->pCoherCharOut,
 132                           pdx->pUrbCharOut->transfer_dma);
 133         usb_free_urb(pdx->pUrbCharOut);
 134
 135         /*  Do the same for chan input */
 136         usb_free_coherent(pdx->udev, INBUF_SZ, pdx->pCoherCharIn,
 137                           pdx->pUrbCharIn->transfer_dma);
 138         usb_free_urb(pdx->pUrbCharIn);
 139
 140         /*  Do the same for the block transfers */
 141         usb_free_coherent(pdx->udev, STAGED_SZ, pdx->pCoherStagedIO,
 142                           pdx->pStagedUrb->transfer_dma);
 143         usb_free_urb(pdx->pStagedUrb);
 144
 145         usb_put_dev(pdx->udev);
 146         kfree(pdx);
 147 }
 148
 149 /*  This is the driver end of the open() call from user space. */
 150 static int ced_open(struct inode *inode, struct file *file)
 151 {
 152         DEVICE_EXTENSION *pdx;
 153         int retval = 0;
 154         int subminor = iminor(inode);
 155         struct usb_interface *interface =
 156             usb_find_interface(&ced_driver, subminor);
 157         if (!interface) {
 158                 pr_err("%s - error, can't find device for minor %d", __func__,
 159                        subminor);
 160                 retval = -ENODEV;
 161                 goto exit;
 162         }
 163
 164         pdx = usb_get_intfdata(interface);
 165         if (!pdx) {
 166                 retval = -ENODEV;
 167                 goto exit;
 168         }
 169
 170         dev_dbg(&interface->dev, "%s got pdx", __func__);
 171
 172         /* increment our usage count for the device */
 173         kref_get(&pdx->kref);
 174
 175         /* lock the device to allow correctly handling errors
 176          * in resumption */
 177         mutex_lock(&pdx->io_mutex);
 178
 179         if (!pdx->open_count++) {
 180                 retval = usb_autopm_get_interface(interface);
 181                 if (retval) {
 182                         pdx->open_count--;
 183                         mutex_unlock(&pdx->io_mutex);
 184                         kref_put(&pdx->kref, ced_delete);
 185                         goto exit;
 186                 }
 187         } else {                /* uncomment this block if you want exclusive open */
 188                 dev_err(&interface->dev, "%s fail: already open", __func__);
 189                 retval = -EBUSY;
 190                 pdx->open_count--;
 191                 mutex_unlock(&pdx->io_mutex);
 192                 kref_put(&pdx->kref, ced_delete);
 193                 goto exit;
 194         }
 195         /* prevent the device from being autosuspended */
 196
 197         /* save our object in the file's private structure */
 198         file->private_data = pdx;
 199         mutex_unlock(&pdx->io_mutex);
 200
 201 exit:
 202         return retval;
 203 }
 204
 205 static int ced_release(struct inode *inode, struct file *file)
 206 {
 207         DEVICE_EXTENSION *pdx = file->private_data;
 208         if (pdx == NULL)
 209                 return -ENODEV;
 210
 211         dev_dbg(&pdx->interface->dev, "%s called", __func__);
 212         mutex_lock(&pdx->io_mutex);
 213         if (!--pdx->open_count && pdx->interface)       /*  Allow autosuspend */
 214                 usb_autopm_put_interface(pdx->interface);
 215         mutex_unlock(&pdx->io_mutex);
 216
 217         kref_put(&pdx->kref, ced_delete);       /*  decrement the count on our device */
 218         return 0;
 219 }
 220
 221 static int ced_flush(struct file *file, fl_owner_t id)
 222 {
 223         int res;
 224         DEVICE_EXTENSION *pdx = file->private_data;
 225         if (pdx == NULL)
 226                 return -ENODEV;
 227
 228         dev_dbg(&pdx->interface->dev, "%s char in pend=%d", __func__,
 229                 pdx->bReadCharsPending);
 230
 231         /* wait for io to stop */
 232         mutex_lock(&pdx->io_mutex);
 233         dev_dbg(&pdx->interface->dev, "%s got io_mutex", __func__);
 234         ced_draw_down(pdx);
 235
 236         /* read out errors, leave subsequent opens a clean slate */
 237         spin_lock_irq(&pdx->err_lock);
 238         res = pdx->errors ? (pdx->errors == -EPIPE ? -EPIPE : -EIO) : 0;
 239         pdx->errors = 0;
 240         spin_unlock_irq(&pdx->err_lock);
 241
 242         mutex_unlock(&pdx->io_mutex);
 243         dev_dbg(&pdx->interface->dev, "%s exit reached", __func__);
 244
 245         return res;
 246 }
 247
 248 /***************************************************************************
 249 ** CanAcceptIoRequests
 250 ** If the device is removed, interface is set NULL. We also clear our pointer
 251 ** from the interface, so we should make sure that pdx is not NULL. This will
 252 ** not help with a device extension held by a file.
 253 ** return true if can accept new io requests, else false
 254 */
 255 static bool CanAcceptIoRequests(DEVICE_EXTENSION *pdx)
 256 {
 257         return pdx && pdx->interface;   /*  Can we accept IO requests */
 258 }
 259
 260 /****************************************************************************
 261 ** Callback routine to complete writes. This may need to fire off another
 262 ** urb to complete the transfer.
 263 ****************************************************************************/
 264 static void ced_writechar_callback(struct urb *pUrb)
 265 {
 266         DEVICE_EXTENSION *pdx = pUrb->context;
 267         int nGot = pUrb->actual_length; /*  what we transferred */
 268
 269         if (pUrb->status) {     /*  sync/async unlink faults aren't errors */
 270                 if (!
 271                     (pUrb->status == -ENOENT || pUrb->status == -ECONNRESET
 272                      || pUrb->status == -ESHUTDOWN)) {
 273                         dev_err(&pdx->interface->dev,
 274                                 "%s - nonzero write bulk status received: %d",
 275                                 __func__, pUrb->status);
 276                 }
 277
 278                 spin_lock(&pdx->err_lock);
 279                 pdx->errors = pUrb->status;
 280                 spin_unlock(&pdx->err_lock);
 281                 nGot = 0;       /*   and tidy up again if so */
 282
 283                 spin_lock(&pdx->charOutLock);   /*  already at irq level */
 284                 pdx->dwOutBuffGet = 0;  /*  Reset the output buffer */
 285                 pdx->dwOutBuffPut = 0;
 286                 pdx->dwNumOutput = 0;   /*  Clear the char count */
 287                 pdx->bPipeError[0] = 1; /*  Flag an error for later */
 288                 pdx->bSendCharsPending = false; /*  Allow other threads again */
 289                 spin_unlock(&pdx->charOutLock); /*  already at irq level */
 290                 dev_dbg(&pdx->interface->dev,
 291                         "%s - char out done, 0 chars sent", __func__);
 292         } else {
 293                 dev_dbg(&pdx->interface->dev,
 294                         "%s - char out done, %d chars sent", __func__, nGot);
 295                 spin_lock(&pdx->charOutLock);   /*  already at irq level */
 296                 pdx->dwNumOutput -= nGot;       /*  Now adjust the char send buffer */
 297                 pdx->dwOutBuffGet += nGot;      /*  to match what we did */
 298                 if (pdx->dwOutBuffGet >= OUTBUF_SZ)     /*  Can't do this any earlier as data could be overwritten */
 299                         pdx->dwOutBuffGet = 0;
 300
 301                 if (pdx->dwNumOutput > 0) {     /*  if more to be done... */
 302                         int nPipe = 0;  /*  The pipe number to use */
 303                         int iReturn;
 304                         char *pDat = &pdx->outputBuffer[pdx->dwOutBuffGet];
 305                         unsigned int dwCount = pdx->dwNumOutput;        /*  maximum to send */
 306                         if ((pdx->dwOutBuffGet + dwCount) > OUTBUF_SZ)  /*  does it cross buffer end? */
 307                                 dwCount = OUTBUF_SZ - pdx->dwOutBuffGet;
 308                         spin_unlock(&pdx->charOutLock); /*  we are done with stuff that changes */
 309                         memcpy(pdx->pCoherCharOut, pDat, dwCount);      /*  copy output data to the buffer */
 310                         usb_fill_bulk_urb(pdx->pUrbCharOut, pdx->udev,
 311                                           usb_sndbulkpipe(pdx->udev,
 312                                                           pdx->epAddr[0]),
 313                                           pdx->pCoherCharOut, dwCount,
 314                                           ced_writechar_callback, pdx);
 315                         pdx->pUrbCharOut->transfer_flags |=
 316                             URB_NO_TRANSFER_DMA_MAP;
 317                         usb_anchor_urb(pdx->pUrbCharOut, &pdx->submitted);      /*  in case we need to kill it */
 318                         iReturn = usb_submit_urb(pdx->pUrbCharOut, GFP_ATOMIC);
 319                         dev_dbg(&pdx->interface->dev, "%s n=%d>%s<", __func__,
 320                                 dwCount, pDat);
 321                         spin_lock(&pdx->charOutLock);   /*  grab lock for errors */
 322                         if (iReturn) {
 323                                 pdx->bPipeError[nPipe] = 1;     /*  Flag an error to be handled later */
 324                                 pdx->bSendCharsPending = false; /*  Allow other threads again */
 325                                 usb_unanchor_urb(pdx->pUrbCharOut);
 326                                 dev_err(&pdx->interface->dev,
 327                                         "%s usb_submit_urb() returned %d",
 328                                         __func__, iReturn);
 329                         }
 330                 } else
 331                         pdx->bSendCharsPending = false; /*  Allow other threads again */
 332                 spin_unlock(&pdx->charOutLock); /*  already at irq level */
 333         }
 334 }
 335
 336 /****************************************************************************
 337 ** SendChars
 338 ** Transmit the characters in the output buffer to the 1401. This may need
 339 ** breaking down into multiple transfers.
 340 ****************************************************************************/
 341 int SendChars(DEVICE_EXTENSION *pdx)
 342 {
 343         int iReturn = U14ERR_NOERROR;
 344
 345         spin_lock_irq(&pdx->charOutLock);       /*  Protect ourselves */
 346
 347         if ((!pdx->bSendCharsPending) &&        /*  Not currently sending */
 348             (pdx->dwNumOutput > 0) &&   /*   has characters to output */
 349             (CanAcceptIoRequests(pdx))) { /*   and current activity is OK */
 350                 unsigned int dwCount = pdx->dwNumOutput;        /*  Get a copy of the character count */
 351                 pdx->bSendCharsPending = true;  /*  Set flag to lock out other threads */
 352
 353                 dev_dbg(&pdx->interface->dev,
 354                         "Send %d chars to 1401, EP0 flag %d\n", dwCount,
 355                         pdx->nPipes == 3);
 356                 /*  If we have only 3 end points we must send the characters to the 1401 using EP0. */
 357                 if (pdx->nPipes == 3) {
 358                         /*  For EP0 character transmissions to the 1401, we have to hang about until they */
 359                         /*  are gone, as otherwise without more character IO activity they will never go. */
 360                         unsigned int count = dwCount;   /*  Local char counter */
 361                         unsigned int index = 0; /*  The index into the char buffer */
 362
 363                         spin_unlock_irq(&pdx->charOutLock);     /*  Free spinlock as we call USBD */
 364
 365                         while ((count > 0) && (iReturn == U14ERR_NOERROR)) {
 366                                 /*  We have to break the transfer up into 64-byte chunks because of a 2270 problem */
 367                                 int n = count > 64 ? 64 : count;        /*  Chars for this xfer, max of 64 */
 368                                 int nSent = usb_control_msg(pdx->udev,
 369                                                             usb_sndctrlpipe(pdx->udev, 0),      /*  use end point 0 */
 370                                                             DB_CHARS,   /*  bRequest */
 371                                                             (H_TO_D | VENDOR | DEVREQ), /*  to the device, vendor request to the device */
 372                                                             0, 0,       /*  value and index are both 0 */
 373                                                             &pdx->outputBuffer[index],  /*  where to send from */
 374                                                             n,  /*  how much to send */
 375                                                             1000);      /*  timeout in jiffies */
 376                                 if (nSent <= 0) {
 377                                         iReturn = nSent ? nSent : -ETIMEDOUT;   /*  if 0 chars says we timed out */
 378                                         dev_err(&pdx->interface->dev,
 379                                                 "Send %d chars by EP0 failed: %d",
 380                                                 n, iReturn);
 381                                 } else {
 382                                         dev_dbg(&pdx->interface->dev,
 383                                                 "Sent %d chars by EP0", n);
 384                                         count -= nSent;
 385                                         index += nSent;
 386                                 }
 387                         }
 388
 389                         spin_lock_irq(&pdx->charOutLock);       /*  Protect pdx changes, released by general code */
 390                         pdx->dwOutBuffGet = 0;  /*  so reset the output buffer */
 391                         pdx->dwOutBuffPut = 0;
 392                         pdx->dwNumOutput = 0;   /*  and clear the buffer count */
 393                         pdx->bSendCharsPending = false; /*  Allow other threads again */
 394                 } else {        /*  Here for sending chars normally - we hold the spin lock */
 395                         int nPipe = 0;  /*  The pipe number to use */
 396                         char *pDat = &pdx->outputBuffer[pdx->dwOutBuffGet];
 397
 398                         if ((pdx->dwOutBuffGet + dwCount) > OUTBUF_SZ)  /*  does it cross buffer end? */
 399                                 dwCount = OUTBUF_SZ - pdx->dwOutBuffGet;
 400                         spin_unlock_irq(&pdx->charOutLock);     /*  we are done with stuff that changes */
 401                         memcpy(pdx->pCoherCharOut, pDat, dwCount);      /*  copy output data to the buffer */
 402                         usb_fill_bulk_urb(pdx->pUrbCharOut, pdx->udev,
 403                                           usb_sndbulkpipe(pdx->udev,
 404                                                           pdx->epAddr[0]),
 405                                           pdx->pCoherCharOut, dwCount,
 406                                           ced_writechar_callback, pdx);
 407                         pdx->pUrbCharOut->transfer_flags |=
 408                             URB_NO_TRANSFER_DMA_MAP;
 409                         usb_anchor_urb(pdx->pUrbCharOut, &pdx->submitted);
 410                         iReturn = usb_submit_urb(pdx->pUrbCharOut, GFP_KERNEL);
 411                         spin_lock_irq(&pdx->charOutLock);       /*  grab lock for errors */
 412                         if (iReturn) {
 413                                 pdx->bPipeError[nPipe] = 1;     /*  Flag an error to be handled later */
 414                                 pdx->bSendCharsPending = false; /*  Allow other threads again */
 415                                 usb_unanchor_urb(pdx->pUrbCharOut);     /*  remove from list of active urbs */
 416                         }
 417                 }
 418         } else if (pdx->bSendCharsPending && (pdx->dwNumOutput > 0))
 419                 dev_dbg(&pdx->interface->dev,
 420                         "SendChars bSendCharsPending:true");
 421
 422         dev_dbg(&pdx->interface->dev, "SendChars exit code: %d", iReturn);
 423         spin_unlock_irq(&pdx->charOutLock);     /*  Now let go of the spinlock */
 424         return iReturn;
 425 }
 426
 427 /***************************************************************************
 428 ** CopyUserSpace
 429 ** This moves memory between pinned down user space and the pCoherStagedIO
 430 ** memory buffer we use for transfers. Copy n bytes in the directions that
 431 ** is defined by pdx->StagedRead. The user space is determined by the area
 432 ** in pdx->StagedId and the offset in pdx->StagedDone. The user
 433 ** area may well not start on a page boundary, so allow for that.
 434 **
 435 ** We have a table of physical pages that describe the area, so we can use
 436 ** this to get a virtual address that the kernel can use.
 437 **
 438 ** pdx  Is our device extension which holds all we know about the transfer.
 439 ** n    The number of bytes to move one way or the other.
 440 ***************************************************************************/
 441 static void CopyUserSpace(DEVICE_EXTENSION *pdx, int n)
 442 {
 443         unsigned int nArea = pdx->StagedId;
 444         if (nArea < MAX_TRANSAREAS) {
 445                 TRANSAREA *pArea = &pdx->rTransDef[nArea];      /*  area to be used */
 446                 unsigned int dwOffset =
 447                     pdx->StagedDone + pdx->StagedOffset + pArea->dwBaseOffset;
 448                 char *pCoherBuf = pdx->pCoherStagedIO;  /*  coherent buffer */
 449                 if (!pArea->bUsed) {
 450                         dev_err(&pdx->interface->dev, "%s area %d unused",
 451                                 __func__, nArea);
 452                         return;
 453                 }
 454
 455                 while (n) {
 456                         int nPage = dwOffset >> PAGE_SHIFT;     /*  page number in table */
 457                         if (nPage < pArea->nPages) {
 458                                 char *pvAddress =
 459                                     (char *)kmap_atomic(pArea->pPages[nPage]);
 460                                 if (pvAddress) {
 461                                         unsigned int uiPageOff = dwOffset & (PAGE_SIZE - 1);    /*  offset into the page */
 462                                         size_t uiXfer = PAGE_SIZE - uiPageOff;  /*  max to transfer on this page */
 463                                         if (uiXfer > n) /*  limit byte count if too much */
 464                                                 uiXfer = n;     /*  for the page */
 465                                         if (pdx->StagedRead)
 466                                                 memcpy(pvAddress + uiPageOff,
 467                                                        pCoherBuf, uiXfer);
 468                                         else
 469                                                 memcpy(pCoherBuf,
 470                                                        pvAddress + uiPageOff,
 471                                                        uiXfer);
 472                                         kunmap_atomic(pvAddress);
 473                                         dwOffset += uiXfer;
 474                                         pCoherBuf += uiXfer;
 475                                         n -= uiXfer;
 476                                 } else {
 477                                         dev_err(&pdx->interface->dev,
 478                                                 "%s did not map page %d",
 479                                                 __func__, nPage);
 480                                         return;
 481                                 }
 482
 483                         } else {
 484                                 dev_err(&pdx->interface->dev,
 485                                         "%s exceeded pages %d", __func__,
 486                                         nPage);
 487                                 return;
 488                         }
 489                 }
 490         } else
 491                 dev_err(&pdx->interface->dev, "%s bad area %d", __func__,
 492                         nArea);
 493 }
 494
 495 /*  Forward declarations for stuff used circularly */
 496 static int StageChunk(DEVICE_EXTENSION *pdx);
 497 /***************************************************************************
 498 ** ReadWrite_Complete
 499 **
 500 **  Completion routine for our staged read/write Irps
 501 */
 502 static void staged_callback(struct urb *pUrb)
 503 {
 504         DEVICE_EXTENSION *pdx = pUrb->context;
 505         unsigned int nGot = pUrb->actual_length;        /*  what we transferred */
 506         bool bCancel = false;
 507         bool bRestartCharInput; /*  used at the end */
 508
 509         spin_lock(&pdx->stagedLock);    /*  stop ReadWriteMem() action while this routine is running */
 510         pdx->bStagedUrbPending = false; /*  clear the flag for staged IRP pending */
 511
 512         if (pUrb->status) {     /*  sync/async unlink faults aren't errors */
 513                 if (!
 514                     (pUrb->status == -ENOENT || pUrb->status == -ECONNRESET
 515                      || pUrb->status == -ESHUTDOWN)) {
 516                         dev_err(&pdx->interface->dev,
 517                                 "%s - nonzero write bulk status received: %d",
 518                                 __func__, pUrb->status);
 519                 } else
 520                         dev_info(&pdx->interface->dev,
 521                                  "%s - staged xfer cancelled", __func__);
 522
 523                 spin_lock(&pdx->err_lock);
 524                 pdx->errors = pUrb->status;
 525                 spin_unlock(&pdx->err_lock);
 526                 nGot = 0;       /*   and tidy up again if so */
 527                 bCancel = true;
 528         } else {
 529                 dev_dbg(&pdx->interface->dev, "%s %d chars xferred", __func__,
 530                         nGot);
 531                 if (pdx->StagedRead)    /*  if reading, save to user space */
 532                         CopyUserSpace(pdx, nGot);       /*  copy from buffer to user */
 533                 if (nGot == 0)
 534                         dev_dbg(&pdx->interface->dev, "%s ZLP", __func__);
 535         }
 536
 537         /*  Update the transfer length based on the TransferBufferLength value in the URB */
 538         pdx->StagedDone += nGot;
 539
 540         dev_dbg(&pdx->interface->dev, "%s, done %d bytes of %d", __func__,
 541                 pdx->StagedDone, pdx->StagedLength);
 542
 543         if ((pdx->StagedDone == pdx->StagedLength) ||   /*  If no more to do */
 544             (bCancel)) {                /*  or this IRP was cancelled */
 545                 TRANSAREA *pArea = &pdx->rTransDef[pdx->StagedId];      /*  Transfer area info */
 546                 dev_dbg(&pdx->interface->dev,
 547                         "%s transfer done, bytes %d, cancel %d", __func__,
 548                         pdx->StagedDone, bCancel);
 549
 550                 /*  Here is where we sort out what to do with this transfer if using a circular buffer. We have */
 551                 /*   a completed transfer that can be assumed to fit into the transfer area. We should be able to */
 552                 /*   add this to the end of a growing block or to use it to start a new block unless the code */
 553                 /*   that calculates the offset to use (in ReadWriteMem) is totally duff. */
 554                 if ((pArea->bCircular) && (pArea->bCircToHost) && (!bCancel) && /*  Time to sort out circular buffer info? */
 555                     (pdx->StagedRead)) {        /*  Only for tohost transfers for now */
 556                         if (pArea->aBlocks[1].dwSize > 0) {     /*  If block 1 is in use we must append to it */
 557                                 if (pdx->StagedOffset ==
 558                                     (pArea->aBlocks[1].dwOffset +
 559                                      pArea->aBlocks[1].dwSize)) {
 560                                         pArea->aBlocks[1].dwSize +=
 561                                             pdx->StagedLength;
 562                                         dev_dbg(&pdx->interface->dev,
 563                                                 "RWM_Complete, circ block 1 now %d bytes at %d",
 564                                                 pArea->aBlocks[1].dwSize,
 565                                                 pArea->aBlocks[1].dwOffset);
 566                                 } else {
 567                                         /*  Here things have gone very, very, wrong, but I cannot see how this can actually be achieved */
 568                                         pArea->aBlocks[1].dwOffset =
 569                                             pdx->StagedOffset;
 570                                         pArea->aBlocks[1].dwSize =
 571                                             pdx->StagedLength;
 572                                         dev_err(&pdx->interface->dev,
 573                                                 "%s ERROR, circ block 1 re-started %d bytes at %d",
 574                                                 __func__,
 575                                                 pArea->aBlocks[1].dwSize,
 576                                                 pArea->aBlocks[1].dwOffset);
 577                                 }
 578                         } else {        /*  If block 1 is not used, we try to add to block 0 */
 579                                 if (pArea->aBlocks[0].dwSize > 0) {     /*  Got stored block 0 information? */
 580                                         /*  Must append onto the existing block 0 */
 581                                         if (pdx->StagedOffset ==
 582                                             (pArea->aBlocks[0].dwOffset +
 583                                              pArea->aBlocks[0].dwSize)) {
 584                                                 pArea->aBlocks[0].dwSize += pdx->StagedLength;  /*  Just add this transfer in */
 585                                                 dev_dbg(&pdx->interface->dev,
 586                                                         "RWM_Complete, circ block 0 now %d bytes at %d",
 587                                                         pArea->aBlocks[0].
 588                                                         dwSize,
 589                                                         pArea->aBlocks[0].
 590                                                         dwOffset);
 591                                         } else {        /*  If it doesn't append, put into new block 1 */
 592                                                 pArea->aBlocks[1].dwOffset =
 593                                                     pdx->StagedOffset;
 594                                                 pArea->aBlocks[1].dwSize =
 595                                                     pdx->StagedLength;
 596                                                 dev_dbg(&pdx->interface->dev,
 597                                                         "RWM_Complete, circ block 1 started %d bytes at %d",
 598                                                         pArea->aBlocks[1].
 599                                                         dwSize,
 600                                                         pArea->aBlocks[1].
 601                                                         dwOffset);
 602                                         }
 603                                 } else  { /*  No info stored yet, just save in block 0 */
 604                                         pArea->aBlocks[0].dwOffset =
 605                                             pdx->StagedOffset;
 606                                         pArea->aBlocks[0].dwSize =
 607                                             pdx->StagedLength;
 608                                         dev_dbg(&pdx->interface->dev,
 609                                                 "RWM_Complete, circ block 0 started %d bytes at %d",
 610                                                 pArea->aBlocks[0].dwSize,
 611                                                 pArea->aBlocks[0].dwOffset);
 612                                 }
 613                         }
 614                 }
 615
 616                 if (!bCancel) { /*  Don't generate an event if cancelled */
 617                         dev_dbg(&pdx->interface->dev,
 618                                 "RWM_Complete,  bCircular %d, bToHost %d, eStart %d, eSize %d",
 619                                 pArea->bCircular, pArea->bEventToHost,
 620                                 pArea->dwEventSt, pArea->dwEventSz);
 621                         if ((pArea->dwEventSz) &&       /*  Set a user-mode event... */
 622                             (pdx->StagedRead == pArea->bEventToHost)) { /*  ...on transfers in this direction? */
 623                                 int iWakeUp = 0;        /*  assume */
 624                                 /*  If we have completed the right sort of DMA transfer then set the event to notify */
 625                                 /*    the user code to wake up anyone that is waiting. */
 626                                 if ((pArea->bCircular) &&       /*  Circular areas use a simpler test */
 627                                     (pArea->bCircToHost)) {     /*  only in supported direction */
 628                                         /*  Is total data waiting up to size limit? */
 629                                         unsigned int dwTotal =
 630                                             pArea->aBlocks[0].dwSize +
 631                                             pArea->aBlocks[1].dwSize;
 632                                         iWakeUp = (dwTotal >= pArea->dwEventSz);
 633                                 } else {
 634                                         unsigned int transEnd =
 635                                             pdx->StagedOffset +
 636                                             pdx->StagedLength;
 637                                         unsigned int eventEnd =
 638                                             pArea->dwEventSt + pArea->dwEventSz;
 639                                         iWakeUp = (pdx->StagedOffset < eventEnd)
 640                                             && (transEnd > pArea->dwEventSt);
 641                                 }
 642
 643                                 if (iWakeUp) {
 644                                         dev_dbg(&pdx->interface->dev,
 645                                                 "About to set event to notify app");
 646                                         wake_up_interruptible(&pArea->wqEvent); /*  wake up waiting processes */
 647                                         ++pArea->iWakeUp;       /*  increment wakeup count */
 648                                 }
 649                         }
 650                 }
 651
 652                 pdx->dwDMAFlag = MODE_CHAR;     /*  Switch back to char mode before ReadWriteMem call */
 653
 654                 if (!bCancel) { /*  Don't look for waiting transfer if cancelled */
 655                         /*  If we have a transfer waiting, kick it off */
 656                         if (pdx->bXFerWaiting) {        /*  Got a block xfer waiting? */
 657                                 int iReturn;
 658                                 dev_info(&pdx->interface->dev,
 659                                          "*** RWM_Complete *** pending transfer will now be set up!!!");
 660                                 iReturn =
 661                                     ReadWriteMem(pdx, !pdx->rDMAInfo.bOutWard,
 662                                                  pdx->rDMAInfo.wIdent,
 663                                                  pdx->rDMAInfo.dwOffset,
 664                                                  pdx->rDMAInfo.dwSize);
 665
 666                                 if (iReturn)
 667                                         dev_err(&pdx->interface->dev,
 668                                                 "RWM_Complete rw setup failed %d",
 669                                                 iReturn);
 670                         }
 671                 }
 672
 673         } else                  /*  Here for more to do */
 674                 StageChunk(pdx);        /*  fire off the next bit */
 675
 676         /*  While we hold the stagedLock, see if we should reallow character input ints */
 677         /*  Don't allow if cancelled, or if a new block has started or if there is a waiting block. */
 678         /*  This feels wrong as we should ask which spin lock protects dwDMAFlag. */
 679         bRestartCharInput = !bCancel && (pdx->dwDMAFlag == MODE_CHAR)
 680             && !pdx->bXFerWaiting;
 681
 682         spin_unlock(&pdx->stagedLock);  /*  Finally release the lock again */
 683
 684         /*  This is not correct as dwDMAFlag is protected by the staged lock, but it is treated */
 685         /*  in Allowi as if it were protected by the char lock. In any case, most systems will */
 686         /*  not be upset by char input during DMA... sigh. Needs sorting out. */
 687         if (bRestartCharInput)  /*  may be out of date, but... */
 688                 Allowi(pdx);    /*  ...Allowi tests a lock too. */
 689         dev_dbg(&pdx->interface->dev, "%s done", __func__);
 690 }
 691
 692 /****************************************************************************
 693 ** StageChunk
 694 **
 695 ** Generates the next chunk of data making up a staged transfer.
 696 **
 697 ** The calling code must have acquired the staging spinlock before calling
 698 **  this function, and is responsible for releasing it. We are at callback level.
 699 ****************************************************************************/
 700 static int StageChunk(DEVICE_EXTENSION *pdx)
 701 {
 702         int iReturn = U14ERR_NOERROR;
 703         unsigned int ChunkSize;
 704         int nPipe = pdx->StagedRead ? 3 : 2;    /*  The pipe number to use for reads or writes */
 705         if (pdx->nPipes == 3)
 706                 nPipe--;        /*  Adjust for the 3-pipe case */
 707         if (nPipe < 0)          /*  and trap case that should never happen */
 708                 return U14ERR_FAIL;
 709
 710         if (!CanAcceptIoRequests(pdx)) {        /*  got sudden remove? */
 711                 dev_info(&pdx->interface->dev, "%s sudden remove, giving up",
 712                          __func__);
 713                 return U14ERR_FAIL;     /*  could do with a better error */
 714         }
 715
 716         ChunkSize = (pdx->StagedLength - pdx->StagedDone);      /*  transfer length remaining */
 717         if (ChunkSize > STAGED_SZ)      /*  make sure to keep legal */
 718                 ChunkSize = STAGED_SZ;  /*   limit to max allowed */
 719
 720         if (!pdx->StagedRead)   /*  if writing... */
 721                 CopyUserSpace(pdx, ChunkSize);  /*  ...copy data into the buffer */
 722
 723         usb_fill_bulk_urb(pdx->pStagedUrb, pdx->udev,
 724                           pdx->StagedRead ? usb_rcvbulkpipe(pdx->udev,
 725                                                             pdx->
 726                                                             epAddr[nPipe]) :
 727                           usb_sndbulkpipe(pdx->udev, pdx->epAddr[nPipe]),
 728                           pdx->pCoherStagedIO, ChunkSize, staged_callback, pdx);
 729         pdx->pStagedUrb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 730         usb_anchor_urb(pdx->pStagedUrb, &pdx->submitted);       /*  in case we need to kill it */
 731         iReturn = usb_submit_urb(pdx->pStagedUrb, GFP_ATOMIC);
 732         if (iReturn) {
 733                 usb_unanchor_urb(pdx->pStagedUrb);      /*  kill it */
 734                 pdx->bPipeError[nPipe] = 1;     /*  Flag an error to be handled later */
 735                 dev_err(&pdx->interface->dev, "%s submit urb failed, code %d",
 736                         __func__, iReturn);
 737         } else
 738                 pdx->bStagedUrbPending = true;  /*  Set the flag for staged URB pending */
 739         dev_dbg(&pdx->interface->dev, "%s done so far:%d, this size:%d",
 740                 __func__, pdx->StagedDone, ChunkSize);
 741
 742         return iReturn;
 743 }
 744
 745 /***************************************************************************
 746 ** ReadWriteMem
 747 **
 748 ** This routine is used generally for block read and write operations.
 749 ** Breaks up a read or write in to specified sized chunks, as specified by pipe
 750 ** information on maximum transfer size.
 751 **
 752 ** Any code that calls this must be holding the stagedLock
 753 **
 754 ** Arguments:
 755 **    DeviceObject - pointer to our FDO (Functional Device Object)
 756 **    Read - TRUE for read, FALSE for write. This is from POV of the driver
 757 **    wIdent - the transfer area number - defines memory area and more.
 758 **    dwOffs - the start offset within the transfer area of the start of this
 759 **             transfer.
 760 **    dwLen - the number of bytes to transfer.
 761 */
 762 int ReadWriteMem(DEVICE_EXTENSION *pdx, bool Read, unsigned short wIdent,
 763                  unsigned int dwOffs, unsigned int dwLen)
 764 {
 765         TRANSAREA *pArea = &pdx->rTransDef[wIdent];     /*  Transfer area info */
 766
 767         if (!CanAcceptIoRequests(pdx)) {        /*  Are we in a state to accept new requests? */
 768                 dev_err(&pdx->interface->dev, "%s can't accept requests",
 769                         __func__);
 770                 return U14ERR_FAIL;
 771         }
 772
 773         dev_dbg(&pdx->interface->dev,
 774                 "%s xfer %d bytes to %s, offset %d, area %d", __func__, dwLen,
 775                 Read ? "host" : "1401", dwOffs, wIdent);
 776
 777         /*  Amazingly, we can get an escape sequence back before the current staged Urb is done, so we */
 778         /*   have to check for this situation and, if so, wait until all is OK. */
 779         if (pdx->bStagedUrbPending) {
 780                 pdx->bXFerWaiting = true;       /*  Flag we are waiting */
 781                 dev_info(&pdx->interface->dev,
 782                          "%s xfer is waiting, as previous staged pending",
 783                          __func__);
 784                 return U14ERR_NOERROR;
 785         }
 786
 787         if (dwLen == 0) {               /*  allow 0-len read or write; just return success */
 788                 dev_dbg(&pdx->interface->dev,
 789                         "%s OK; zero-len read/write request", __func__);
 790                 return U14ERR_NOERROR;
 791         }
 792
 793         if ((pArea->bCircular) &&       /*  Circular transfer? */
 794             (pArea->bCircToHost) && (Read)) {   /*  In a supported direction */
 795                                 /*  If so, we sort out offset ourself */
 796                 bool bWait = false;     /*  Flag for transfer having to wait */
 797
 798                 dev_dbg(&pdx->interface->dev,
 799                         "Circular buffers are %d at %d and %d at %d",
 800                         pArea->aBlocks[0].dwSize, pArea->aBlocks[0].dwOffset,
 801                         pArea->aBlocks[1].dwSize, pArea->aBlocks[1].dwOffset);
 802                 if (pArea->aBlocks[1].dwSize > 0) {     /*  Using the second block already? */
 803                         dwOffs = pArea->aBlocks[1].dwOffset + pArea->aBlocks[1].dwSize; /*  take offset from that */
 804                         bWait = (dwOffs + dwLen) > pArea->aBlocks[0].dwOffset;  /*  Wait if will overwrite block 0? */
 805                         bWait |= (dwOffs + dwLen) > pArea->dwLength;    /*  or if it overflows the buffer */
 806                 } else {                /*  Area 1 not in use, try to use area 0 */
 807                         if (pArea->aBlocks[0].dwSize == 0)      /*  Reset block 0 if not in use */
 808                                 pArea->aBlocks[0].dwOffset = 0;
 809                         dwOffs =
 810                             pArea->aBlocks[0].dwOffset +
 811                             pArea->aBlocks[0].dwSize;
 812                         if ((dwOffs + dwLen) > pArea->dwLength) {       /*  Off the end of the buffer? */
 813                                 pArea->aBlocks[1].dwOffset = 0; /*  Set up to use second block */
 814                                 dwOffs = 0;
 815                                 bWait = (dwOffs + dwLen) > pArea->aBlocks[0].dwOffset;  /*  Wait if will overwrite block 0? */
 816                                 bWait |= (dwOffs + dwLen) > pArea->dwLength;    /*  or if it overflows the buffer */
 817                         }
 818                 }
 819
 820                 if (bWait) {    /*  This transfer will have to wait? */
 821                         pdx->bXFerWaiting = true;       /*  Flag we are waiting */
 822                         dev_dbg(&pdx->interface->dev,
 823                                 "%s xfer waiting for circular buffer space",
 824                                 __func__);
 825                         return U14ERR_NOERROR;
 826                 }
 827
 828                 dev_dbg(&pdx->interface->dev,
 829                         "%s circular xfer, %d bytes starting at %d", __func__,
 830                         dwLen, dwOffs);
 831         }
 832         /*  Save the parameters for the read\write transfer */
 833         pdx->StagedRead = Read; /*  Save the parameters for this read */
 834         pdx->StagedId = wIdent; /*  ID allows us to get transfer area info */
 835         pdx->StagedOffset = dwOffs;     /*  The area within the transfer area */
 836         pdx->StagedLength = dwLen;
 837         pdx->StagedDone = 0;    /*  Initialise the byte count */
 838         pdx->dwDMAFlag = MODE_LINEAR;   /*  Set DMA mode flag at this point */
 839         pdx->bXFerWaiting = false;      /*  Clearly not a transfer waiting now */
 840
 841 /*     KeClearEvent(&pdx->StagingDoneEvent);           // Clear the transfer done event */
 842         StageChunk(pdx);        /*  fire off the first chunk */
 843
 844         return U14ERR_NOERROR;
 845 }
 846
 847 /****************************************************************************
 848 **
 849 ** ReadChar
 850 **
 851 ** Reads a character a buffer. If there is no more
 852 **  data we return FALSE. Used as part of decoding a DMA request.
 853 **
 854 ****************************************************************************/
 855 static bool ReadChar(unsigned char *pChar, char *pBuf, unsigned int *pdDone,
 856                      unsigned int dGot)
 857 {
 858         bool bRead = false;
 859         unsigned int dDone = *pdDone;
 860
 861         if (dDone < dGot) {     /*  If there is more data */
 862                 *pChar = (unsigned char)pBuf[dDone];    /*  Extract the next char */
 863                 dDone++;        /*  Increment the done count */
 864                 *pdDone = dDone;
 865                 bRead = true;   /*  and flag success */
 866         }
 867
 868         return bRead;
 869 }
 870
 871 #ifdef NOTUSED
 872 /****************************************************************************
 873 **
 874 ** ReadWord
 875 **
 876 ** Reads a word from the 1401, just uses ReadChar twice; passes on any error
 877 **
 878 *****************************************************************************/
 879 static bool ReadWord(unsigned short *pWord, char *pBuf, unsigned int *pdDone,
 880                      unsigned int dGot)
 881 {
 882         if (ReadChar((unsigned char *)pWord, pBuf, pdDone, dGot))
 883                 return ReadChar(((unsigned char *)pWord) + 1, pBuf, pdDone,
 884                                 dGot);
 885         else
 886                 return false;
 887 }
 888 #endif
 889
 890 /****************************************************************************
 891 ** ReadHuff
 892 **
 893 ** Reads a coded number in and returns it, Code is:
 894 ** If data is in range 0..127 we receive 1 byte. If data in range 128-16383
 895 ** we receive two bytes, top bit of first indicates another on its way. If
 896 ** data in range 16384-4194303 we get three bytes, top two bits of first set
 897 ** to indicate three byte total.
 898 **
 899 *****************************************************************************/
 900 static bool ReadHuff(volatile unsigned int *pDWord, char *pBuf,
 901                      unsigned int *pdDone, unsigned int dGot)
 902 {
 903         unsigned char ucData;   /* for each read to ReadChar */
 904         bool bReturn = true;    /* assume we will succeed */
 905         unsigned int dwData = 0;        /* Accumulator for the data */
 906
 907         if (ReadChar(&ucData, pBuf, pdDone, dGot)) {
 908                 dwData = ucData;        /* copy the data */
 909                 if ((dwData & 0x00000080) != 0) {       /* Bit set for more data ? */
 910                         dwData &= 0x0000007F;   /* Clear the relevant bit */
 911                         if (ReadChar(&ucData, pBuf, pdDone, dGot)) {
 912                                 dwData = (dwData << 8) | ucData;
 913                                 if ((dwData & 0x00004000) != 0) {       /* three byte sequence ? */
 914                                         dwData &= 0x00003FFF;   /* Clear the relevant bit */
 915                                         if (ReadChar
 916                                             (&ucData, pBuf, pdDone, dGot))
 917                                                 dwData = (dwData << 8) | ucData;
 918                                         else
 919                                                 bReturn = false;
 920                                 }
 921                         } else
 922                                 bReturn = false;        /* couldn't read data */
 923                 }
 924         } else
 925                 bReturn = false;
 926
 927         *pDWord = dwData;       /* return the data */
 928         return bReturn;
 929 }
 930
 931 /***************************************************************************
 932 **
 933 ** ReadDMAInfo
 934 **
 935 ** Tries to read info about the dma request from the 1401 and decode it into
 936 ** the dma descriptor block. We have at this point had the escape character
 937 ** from the 1401 and now we must read in the rest of the information about
 938 ** the transfer request. Returns FALSE if 1401 fails to respond or obselete
 939 ** code from 1401 or bad parameters.
 940 **
 941 ** The pBuf char pointer does not include the initial escape character, so
 942 **  we start handling the data at offset zero.
 943 **
 944 *****************************************************************************/
 945 static bool ReadDMAInfo(volatile DMADESC *pDmaDesc, DEVICE_EXTENSION *pdx,
 946                         char *pBuf, unsigned int dwCount)
 947 {
 948         bool bResult = false;   /*  assume we won't succeed */
 949         unsigned char ucData;
 950         unsigned int dDone = 0; /*  We haven't parsed anything so far */
 951
 952         dev_dbg(&pdx->interface->dev, "%s", __func__);
 953
 954         if (ReadChar(&ucData, pBuf, &dDone, dwCount)) {
 955                 unsigned char ucTransCode = (ucData & 0x0F);    /*  get code for transfer type */
 956                 unsigned short wIdent = ((ucData >> 4) & 0x07); /*  and area identifier */
 957
 958                 /*  fill in the structure we were given */
 959                 pDmaDesc->wTransType = ucTransCode;     /*  type of transfer */
 960                 pDmaDesc->wIdent = wIdent;      /*  area to use */
 961                 pDmaDesc->dwSize = 0;   /*  initialise other bits */
 962                 pDmaDesc->dwOffset = 0;
 963
 964                 dev_dbg(&pdx->interface->dev, "%s type: %d ident: %d", __func__,
 965                         pDmaDesc->wTransType, pDmaDesc->wIdent);
 966
 967                 pDmaDesc->bOutWard = (ucTransCode != TM_EXTTOHOST);     /*  set transfer direction */
 968
 969                 switch (ucTransCode) {
 970                 case TM_EXTTOHOST:      /*  Extended linear transfer modes (the only ones!) */
 971                 case TM_EXTTO1401:
 972                         {
 973                                 bResult =
 974                                     ReadHuff(&(pDmaDesc->dwOffset), pBuf,
 975                                              &dDone, dwCount)
 976                                     && ReadHuff(&(pDmaDesc->dwSize), pBuf,
 977                                                 &dDone, dwCount);
 978                                 if (bResult) {
 979                                         dev_dbg(&pdx->interface->dev,
 980                                                 "%s xfer offset & size %d %d",
 981                                                 __func__, pDmaDesc->dwOffset,
 982                                                 pDmaDesc->dwSize);
 983
 984                                         if ((wIdent >= MAX_TRANSAREAS) ||       /*  Illegal area number, or... */
 985                                             (!pdx->rTransDef[wIdent].bUsed) ||  /*  area not set up, or... */
 986                                             (pDmaDesc->dwOffset > pdx->rTransDef[wIdent].dwLength) ||   /*  range/size */
 987                                             ((pDmaDesc->dwOffset +
 988                                               pDmaDesc->dwSize) >
 989                                              (pdx->rTransDef[wIdent].
 990                                               dwLength))) {
 991                                                 bResult = false;        /*  bad parameter(s) */
 992                                                 dev_dbg(&pdx->interface->dev,
 993                                                         "%s bad param - id %d, bUsed %d, offset %d, size %d, area length %d",
 994                                                         __func__, wIdent,
 995                                                         pdx->rTransDef[wIdent].
 996                                                         bUsed,
 997                                                         pDmaDesc->dwOffset,
 998                                                         pDmaDesc->dwSize,
 999                                                         pdx->rTransDef[wIdent].
1000                                                         dwLength);
1001                                         }
1002                                 }
1003                                 break;
1004                         }
1005                 default:
1006                         break;
1007                 }
1008         } else
1009                 bResult = false;
1010
1011         if (!bResult)           /*  now check parameters for validity */
1012                 dev_err(&pdx->interface->dev, "%s error reading Esc sequence",
1013                         __func__);
1014
1015         return bResult;
1016 }
1017
1018 /****************************************************************************
1019 **
1020 ** Handle1401Esc
1021 **
1022 ** Deals with an escape sequence coming from the 1401. This can either be
1023 **  a DMA transfer request of various types or a response to an escape sequence
1024 **  sent to the 1401. This is called from a callback.
1025 **
1026 ** Parameters are
1027 **
1028 ** dwCount - the number of characters in the device extension char in buffer,
1029 **           this is known to be at least 2 or we will not be called.
1030 **
1031 ****************************************************************************/
1032 static int Handle1401Esc(DEVICE_EXTENSION *pdx, char *pCh,
1033                          unsigned int dwCount)
1034 {
1035         int iReturn = U14ERR_FAIL;
1036
1037         /*  I have no idea what this next test is about. '?' is 0x3f, which is area 3, code */
1038         /*  15. At the moment, this is not used, so it does no harm, but unless someone can */
1039         /*  tell me what this is for, it should be removed from this and the Windows driver. */
1040         if (pCh[0] == '?') {    /*  Is this an information response */
1041                                 /*  Parse and save the information */
1042         } else {
1043                 spin_lock(&pdx->stagedLock);    /*  Lock others out */
1044
1045                 if (ReadDMAInfo(&pdx->rDMAInfo, pdx, pCh, dwCount)) {   /*  Get DMA parameters */
1046                         unsigned short wTransType = pdx->rDMAInfo.wTransType;   /*  check transfer type */
1047
1048                         dev_dbg(&pdx->interface->dev,
1049                                 "%s xfer to %s, offset %d, length %d", __func__,
1050                                 pdx->rDMAInfo.bOutWard ? "1401" : "host",
1051                                 pdx->rDMAInfo.dwOffset, pdx->rDMAInfo.dwSize);
1052
1053                         if (pdx->bXFerWaiting) { /*  Check here for badly out of kilter... */
1054                                 /*  This can never happen, really */
1055                                 dev_err(&pdx->interface->dev,
1056                                         "ERROR: DMA setup while transfer still waiting");
1057                                 spin_unlock(&pdx->stagedLock);
1058                         } else {
1059                                 if ((wTransType == TM_EXTTOHOST)
1060                                     || (wTransType == TM_EXTTO1401)) {
1061                                         iReturn =
1062                                             ReadWriteMem(pdx,
1063                                                          !pdx->rDMAInfo.
1064                                                          bOutWard,
1065                                                          pdx->rDMAInfo.wIdent,
1066                                                          pdx->rDMAInfo.dwOffset,
1067                                                          pdx->rDMAInfo.dwSize);
1068                                         if (iReturn != U14ERR_NOERROR)
1069                                                 dev_err(&pdx->interface->dev,
1070                                                         "%s ReadWriteMem() failed %d",
1071                                                         __func__, iReturn);
1072                                 } else  /*  This covers non-linear transfer setup */
1073                                         dev_err(&pdx->interface->dev,
1074                                                 "%s Unknown block xfer type %d",
1075                                                 __func__, wTransType);
1076                         }
1077                 } else          /*  Failed to read parameters */
1078                         dev_err(&pdx->interface->dev, "%s ReadDMAInfo() fail",
1079                                 __func__);
1080
1081                 spin_unlock(&pdx->stagedLock);  /*  OK here */
1082         }
1083
1084         dev_dbg(&pdx->interface->dev, "%s returns %d", __func__, iReturn);
1085
1086         return iReturn;
1087 }
1088
1089 /****************************************************************************
1090 ** Callback for the character read complete or error
1091 ****************************************************************************/
1092 static void ced_readchar_callback(struct urb *pUrb)
1093 {
1094         DEVICE_EXTENSION *pdx = pUrb->context;
1095         int nGot = pUrb->actual_length; /*  what we transferred */
1096
1097         if (pUrb->status) {     /*  Do we have a problem to handle? */
1098                 int nPipe = pdx->nPipes == 4 ? 1 : 0;   /*  The pipe number to use for error */
1099                 /*  sync/async unlink faults aren't errors... just saying device removed or stopped */
1100                 if (!
1101                     (pUrb->status == -ENOENT || pUrb->status == -ECONNRESET
1102                      || pUrb->status == -ESHUTDOWN)) {
1103                         dev_err(&pdx->interface->dev,
1104                                 "%s - nonzero write bulk status received: %d",
1105                                 __func__, pUrb->status);
1106                 } else
1107                         dev_dbg(&pdx->interface->dev,
1108                                 "%s - 0 chars pUrb->status=%d (shutdown?)",
1109                                 __func__, pUrb->status);
1110
1111                 spin_lock(&pdx->err_lock);
1112                 pdx->errors = pUrb->status;
1113                 spin_unlock(&pdx->err_lock);
1114                 nGot = 0;       /*   and tidy up again if so */
1115
1116                 spin_lock(&pdx->charInLock);    /*  already at irq level */
1117                 pdx->bPipeError[nPipe] = 1;     /*  Flag an error for later */
1118         } else {
1119                 if ((nGot > 1) && ((pdx->pCoherCharIn[0] & 0x7f) == 0x1b)) {    /*  Esc sequence? */
1120                         Handle1401Esc(pdx, &pdx->pCoherCharIn[1], nGot - 1);    /*  handle it */
1121                         spin_lock(&pdx->charInLock);    /*  already at irq level */
1122                 } else {
1123                         spin_lock(&pdx->charInLock);    /*  already at irq level */
1124                         if (nGot > 0) {
1125                                 unsigned int i;
1126                                 if (nGot < INBUF_SZ) {
1127                                         pdx->pCoherCharIn[nGot] = 0;    /*  tidy the string */
1128                                         dev_dbg(&pdx->interface->dev,
1129                                                 "%s got %d chars >%s<",
1130                                                 __func__, nGot,
1131                                                 pdx->pCoherCharIn);
1132                                 }
1133                                 /*  We know that whatever we read must fit in the input buffer */
1134                                 for (i = 0; i < nGot; i++) {
1135                                         pdx->inputBuffer[pdx->dwInBuffPut++] =
1136                                             pdx->pCoherCharIn[i] & 0x7F;
1137                                         if (pdx->dwInBuffPut >= INBUF_SZ)
1138                                                 pdx->dwInBuffPut = 0;
1139                                 }
1140
1141                                 if ((pdx->dwNumInput + nGot) <= INBUF_SZ)
1142                                         pdx->dwNumInput += nGot;        /*  Adjust the buffer count accordingly */
1143                         } else
1144                                 dev_dbg(&pdx->interface->dev, "%s read ZLP",
1145                                         __func__);
1146                 }
1147         }
1148
1149         pdx->bReadCharsPending = false; /*  No longer have a pending read */
1150         spin_unlock(&pdx->charInLock);  /*  already at irq level */
1151
1152         Allowi(pdx);    /*  see if we can do the next one */
1153 }
1154
1155 /****************************************************************************
1156 ** Allowi
1157 **
1158 ** This is used to make sure that there is always a pending input transfer so
1159 ** we can pick up any inward transfers. This can be called in multiple contexts
1160 ** so we use the irqsave version of the spinlock.
1161 ****************************************************************************/
1162 int Allowi(DEVICE_EXTENSION *pdx)
1163 {
1164         int iReturn = U14ERR_NOERROR;
1165         unsigned long flags;
1166         spin_lock_irqsave(&pdx->charInLock, flags);     /*  can be called in multiple contexts */
1167
1168         /*  We don't want char input running while DMA is in progress as we know that this */
1169         /*   can cause sequencing problems for the 2270. So don't. It will also allow the */
1170         /*   ERR response to get back to the host code too early on some PCs, even if there */
1171         /*   is no actual driver failure, so we don't allow this at all. */
1172         if (!pdx->bInDrawDown &&        /*  stop input if */
1173             !pdx->bReadCharsPending &&  /*  If no read request outstanding */
1174             (pdx->dwNumInput < (INBUF_SZ / 2)) &&       /*   and there is some space */
1175             (pdx->dwDMAFlag == MODE_CHAR) &&    /*   not doing any DMA */
1176             (!pdx->bXFerWaiting) &&     /*   no xfer waiting to start */
1177             (CanAcceptIoRequests(pdx))) { /*   and activity is generally OK */
1178                                 /*   then off we go */
1179                 unsigned int nMax = INBUF_SZ - pdx->dwNumInput; /*  max we could read */
1180                 int nPipe = pdx->nPipes == 4 ? 1 : 0;   /*  The pipe number to use */
1181
1182                 dev_dbg(&pdx->interface->dev, "%s %d chars in input buffer",
1183                         __func__, pdx->dwNumInput);
1184
1185                 usb_fill_int_urb(pdx->pUrbCharIn, pdx->udev,
1186                                  usb_rcvintpipe(pdx->udev, pdx->epAddr[nPipe]),
1187                                  pdx->pCoherCharIn, nMax, ced_readchar_callback,
1188                                  pdx, pdx->bInterval);
1189                 pdx->pUrbCharIn->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;     /*  short xfers are OK by default */
1190                 usb_anchor_urb(pdx->pUrbCharIn, &pdx->submitted);       /*  in case we need to kill it */
1191                 iReturn = usb_submit_urb(pdx->pUrbCharIn, GFP_ATOMIC);
1192                 if (iReturn) {
1193                         usb_unanchor_urb(pdx->pUrbCharIn);      /*  remove from list of active Urbs */
1194                         pdx->bPipeError[nPipe] = 1;     /*  Flag an error to be handled later */
1195                         dev_err(&pdx->interface->dev,
1196                                 "%s submit urb failed: %d", __func__, iReturn);
1197                 } else
1198                         pdx->bReadCharsPending = true;  /*  Flag that we are active here */
1199         }
1200
1201         spin_unlock_irqrestore(&pdx->charInLock, flags);
1202
1203         return iReturn;
1204
1205 }
1206
1207 /*****************************************************************************
1208 ** The ioctl entry point to the driver that is used by us to talk to it.
1209 ** inode    The device node (no longer in 3.0.0 kernels)
1210 ** file     The file that is open, which holds our pdx pointer
1211 ** ulArg    The argument passed in. Note that long is 64-bits in 64-bit system, i.e. it is big
1212 **          enough for a 64-bit pointer.
1213 *****************************************************************************/
1214 static long ced_ioctl(struct file *file, unsigned int cmd, unsigned long ulArg)
1215 {
1216         int err = 0;
1217         DEVICE_EXTENSION *pdx = file->private_data;
1218         if (!CanAcceptIoRequests(pdx))  /*  check we still exist */
1219                 return -ENODEV;
1220
1221         /*  Check that access is allowed, where is is needed. Anything that would have an indeterminate */
1222         /*  size will be checked by the specific command. */
1223         if (_IOC_DIR(cmd) & _IOC_READ)  /*  read from point of view of user... */
1224                 err = !access_ok(VERIFY_WRITE, (void __user *)ulArg, _IOC_SIZE(cmd));   /*  is kernel write */
1225         else if (_IOC_DIR(cmd) & _IOC_WRITE)    /*  and write from point of view of user... */
1226                 err = !access_ok(VERIFY_READ, (void __user *)ulArg, _IOC_SIZE(cmd));    /*  is kernel read */
1227         if (err)
1228                 return -EFAULT;
1229
1230         switch (_IOC_NR(cmd)) {
1231         case _IOC_NR(IOCTL_CED_SENDSTRING(0)):
1232                 return SendString(pdx, (const char __user *)ulArg,
1233                                   _IOC_SIZE(cmd));
1234
1235         case _IOC_NR(IOCTL_CED_RESET1401):
1236                 return Reset1401(pdx);
1237
1238         case _IOC_NR(IOCTL_CED_GETCHAR):
1239                 return GetChar(pdx);
1240
1241         case _IOC_NR(IOCTL_CED_SENDCHAR):
1242                 return SendChar(pdx, (char)ulArg);
1243
1244         case _IOC_NR(IOCTL_CED_STAT1401):
1245                 return Stat1401(pdx);
1246
1247         case _IOC_NR(IOCTL_CED_LINECOUNT):
1248                 return LineCount(pdx);
1249
1250         case _IOC_NR(IOCTL_CED_GETSTRING(0)):
1251                 return GetString(pdx, (char __user *)ulArg, _IOC_SIZE(cmd));
1252
1253         case _IOC_NR(IOCTL_CED_SETTRANSFER):
1254                 return SetTransfer(pdx, (TRANSFERDESC __user *) ulArg);
1255
1256         case _IOC_NR(IOCTL_CED_UNSETTRANSFER):
1257                 return UnsetTransfer(pdx, (int)ulArg);
1258
1259         case _IOC_NR(IOCTL_CED_SETEVENT):
1260                 return SetEvent(pdx, (TRANSFEREVENT __user *) ulArg);
1261
1262         case _IOC_NR(IOCTL_CED_GETOUTBUFSPACE):
1263                 return GetOutBufSpace(pdx);
1264
1265         case _IOC_NR(IOCTL_CED_GETBASEADDRESS):
1266                 return -1;
1267
1268         case _IOC_NR(IOCTL_CED_GETDRIVERREVISION):
1269                 return (2 << 24) | (DRIVERMAJREV << 16) | DRIVERMINREV; /*  USB | MAJOR | MINOR */
1270
1271         case _IOC_NR(IOCTL_CED_GETTRANSFER):
1272                 return GetTransfer(pdx, (TGET_TX_BLOCK __user *) ulArg);
1273
1274         case _IOC_NR(IOCTL_CED_KILLIO1401):
1275                 return KillIO1401(pdx);
1276
1277         case _IOC_NR(IOCTL_CED_STATEOF1401):
1278                 return StateOf1401(pdx);
1279
1280         case _IOC_NR(IOCTL_CED_GRAB1401):
1281         case _IOC_NR(IOCTL_CED_FREE1401):
1282                 return U14ERR_NOERROR;
1283
1284         case _IOC_NR(IOCTL_CED_STARTSELFTEST):
1285                 return StartSelfTest(pdx);
1286
1287         case _IOC_NR(IOCTL_CED_CHECKSELFTEST):
1288                 return CheckSelfTest(pdx, (TGET_SELFTEST __user *) ulArg);
1289
1290         case _IOC_NR(IOCTL_CED_TYPEOF1401):
1291                 return TypeOf1401(pdx);
1292
1293         case _IOC_NR(IOCTL_CED_TRANSFERFLAGS):
1294                 return TransferFlags(pdx);
1295
1296         case _IOC_NR(IOCTL_CED_DBGPEEK):
1297                 return DbgPeek(pdx, (TDBGBLOCK __user *) ulArg);
1298
1299         case _IOC_NR(IOCTL_CED_DBGPOKE):
1300                 return DbgPoke(pdx, (TDBGBLOCK __user *) ulArg);
1301
1302         case _IOC_NR(IOCTL_CED_DBGRAMPDATA):
1303                 return DbgRampData(pdx, (TDBGBLOCK __user *) ulArg);
1304
1305         case _IOC_NR(IOCTL_CED_DBGRAMPADDR):
1306                 return DbgRampAddr(pdx, (TDBGBLOCK __user *) ulArg);
1307
1308         case _IOC_NR(IOCTL_CED_DBGGETDATA):
1309                 return DbgGetData(pdx, (TDBGBLOCK __user *) ulArg);
1310
1311         case _IOC_NR(IOCTL_CED_DBGSTOPLOOP):
1312                 return DbgStopLoop(pdx);
1313
1314         case _IOC_NR(IOCTL_CED_FULLRESET):
1315                 pdx->bForceReset = true;        /*  Set a flag for a full reset */
1316                 break;
1317
1318         case _IOC_NR(IOCTL_CED_SETCIRCULAR):
1319                 return SetCircular(pdx, (TRANSFERDESC __user *) ulArg);
1320
1321         case _IOC_NR(IOCTL_CED_GETCIRCBLOCK):
1322                 return GetCircBlock(pdx, (TCIRCBLOCK __user *) ulArg);
1323
1324         case _IOC_NR(IOCTL_CED_FREECIRCBLOCK):
1325                 return FreeCircBlock(pdx, (TCIRCBLOCK __user *) ulArg);
1326
1327         case _IOC_NR(IOCTL_CED_WAITEVENT):
1328                 return WaitEvent(pdx, (int)(ulArg & 0xff), (int)(ulArg >> 8));
1329
1330         case _IOC_NR(IOCTL_CED_TESTEVENT):
1331                 return TestEvent(pdx, (int)ulArg);
1332
1333         default:
1334                 return U14ERR_NO_SUCH_FN;
1335         }
1336         return U14ERR_NOERROR;
1337 }
1338
1339 static const struct file_operations ced_fops = {
1340         .owner = THIS_MODULE,
1341         .open = ced_open,
1342         .release = ced_release,
1343         .flush = ced_flush,
1344         .llseek = noop_llseek,
1345         .unlocked_ioctl = ced_ioctl,
1346 };
1347
1348 /*
1349  * usb class driver info in order to get a minor number from the usb core,
1350  * and to have the device registered with the driver core
1351  */
1352 static struct usb_class_driver ced_class = {
1353         .name = "cedusb%d",
1354         .fops = &ced_fops,
1355         .minor_base = USB_CED_MINOR_BASE,
1356 };
1357
1358 /*  Check that the device that matches a 1401 vendor and product ID is OK to use and */
1359 /*  initialise our DEVICE_EXTENSION. */
1360 static int ced_probe(struct usb_interface *interface,
1361                      const struct usb_device_id *id)
1362 {
1363         DEVICE_EXTENSION *pdx;
1364         struct usb_host_interface *iface_desc;
1365         struct usb_endpoint_descriptor *endpoint;
1366         int i, bcdDevice;
1367         int retval = -ENOMEM;
1368
1369         /*  allocate memory for our device extension and initialize it */
1370         pdx = kzalloc(sizeof(*pdx), GFP_KERNEL);
1371         if (!pdx)
1372                 goto error;
1373
1374         for (i = 0; i < MAX_TRANSAREAS; ++i) {  /*  Initialise the wait queues */
1375                 init_waitqueue_head(&pdx->rTransDef[i].wqEvent);
1376         }
1377
1378         /*  Put initialises for our stuff here. Note that all of *pdx is zero, so */
1379         /*  no need to explicitly zero it. */
1380         spin_lock_init(&pdx->charOutLock);
1381         spin_lock_init(&pdx->charInLock);
1382         spin_lock_init(&pdx->stagedLock);
1383
1384         /*  Initialises from the skeleton stuff */
1385         kref_init(&pdx->kref);
1386         mutex_init(&pdx->io_mutex);
1387         spin_lock_init(&pdx->err_lock);
1388         init_usb_anchor(&pdx->submitted);
1389
1390         pdx->udev = usb_get_dev(interface_to_usbdev(interface));
1391         pdx->interface = interface;
1392
1393         /*  Attempt to identify the device */
1394         bcdDevice = pdx->udev->descriptor.bcdDevice;
1395         i = (bcdDevice >> 8);
1396         if (i == 0)
1397                 pdx->s1401Type = TYPEU1401;
1398         else if ((i >= 1) && (i <= 23))
1399                 pdx->s1401Type = i + 2;
1400         else {
1401                 dev_err(&interface->dev, "%s Unknown device. bcdDevice = %d",
1402                         __func__, bcdDevice);
1403                 goto error;
1404         }
1405         /*  set up the endpoint information. We only care about the number of EP as */
1406         /*  we know that we are dealing with a 1401 device. */
1407         iface_desc = interface->cur_altsetting;
1408         pdx->nPipes = iface_desc->desc.bNumEndpoints;
1409         dev_info(&interface->dev, "1401Type=%d with %d End Points",
1410                  pdx->s1401Type, pdx->nPipes);
1411         if ((pdx->nPipes < 3) || (pdx->nPipes > 4))
1412                 goto error;
1413
1414         /*  Allocate the URBs we hold for performing transfers */
1415         pdx->pUrbCharOut = usb_alloc_urb(0, GFP_KERNEL);        /*  character output URB */
1416         pdx->pUrbCharIn = usb_alloc_urb(0, GFP_KERNEL); /*  character input URB */
1417         pdx->pStagedUrb = usb_alloc_urb(0, GFP_KERNEL); /*  block transfer URB */
1418         if (!pdx->pUrbCharOut || !pdx->pUrbCharIn || !pdx->pStagedUrb) {
1419                 dev_err(&interface->dev, "%s URB alloc failed", __func__);
1420                 goto error;
1421         }
1422
1423         pdx->pCoherStagedIO =
1424             usb_alloc_coherent(pdx->udev, STAGED_SZ, GFP_KERNEL,
1425                                &pdx->pStagedUrb->transfer_dma);
1426         pdx->pCoherCharOut =
1427             usb_alloc_coherent(pdx->udev, OUTBUF_SZ, GFP_KERNEL,
1428                                &pdx->pUrbCharOut->transfer_dma);
1429         pdx->pCoherCharIn =
1430             usb_alloc_coherent(pdx->udev, INBUF_SZ, GFP_KERNEL,
1431                                &pdx->pUrbCharIn->transfer_dma);
1432         if (!pdx->pCoherCharOut || !pdx->pCoherCharIn || !pdx->pCoherStagedIO) {
1433                 dev_err(&interface->dev, "%s Coherent buffer alloc failed",
1434                         __func__);
1435                 goto error;
1436         }
1437
1438         for (i = 0; i < pdx->nPipes; ++i) {
1439                 endpoint = &iface_desc->endpoint[i].desc;
1440                 pdx->epAddr[i] = endpoint->bEndpointAddress;
1441                 dev_info(&interface->dev, "Pipe %d, ep address %02x", i,
1442                          pdx->epAddr[i]);
1443                 if (((pdx->nPipes == 3) && (i == 0)) || /*  if char input end point */
1444                     ((pdx->nPipes == 4) && (i == 1))) {
1445                         pdx->bInterval = endpoint->bInterval;   /*  save the endpoint interrupt interval */
1446                         dev_info(&interface->dev, "Pipe %d, bInterval = %d", i,
1447                                  pdx->bInterval);
1448                 }
1449                 /*  Detect USB2 by checking last ep size (64 if USB1) */
1450                 if (i == pdx->nPipes - 1) {     /*  if this is the last ep (bulk) */
1451                         pdx->bIsUSB2 =
1452                             le16_to_cpu(endpoint->wMaxPacketSize) > 64;
1453                         dev_info(&pdx->interface->dev, "USB%d",
1454                                  pdx->bIsUSB2 + 1);
1455                 }
1456         }
1457
1458         /* save our data pointer in this interface device */
1459         usb_set_intfdata(interface, pdx);
1460
1461         /* we can register the device now, as it is ready */
1462         retval = usb_register_dev(interface, &ced_class);
1463         if (retval) {
1464                 /* something prevented us from registering this driver */
1465                 dev_err(&interface->dev,
1466                         "Not able to get a minor for this device.\n");
1467                 usb_set_intfdata(interface, NULL);
1468                 goto error;
1469         }
1470
1471         /* let the user know what node this device is now attached to */
1472         dev_info(&interface->dev,
1473                  "USB CEDUSB device now attached to cedusb #%d",
1474                  interface->minor);
1475         return 0;
1476
1477 error:
1478         if (pdx)
1479                 kref_put(&pdx->kref, ced_delete);       /*  frees allocated memory */
1480         return retval;
1481 }
1482
1483 static void ced_disconnect(struct usb_interface *interface)
1484 {
1485         DEVICE_EXTENSION *pdx = usb_get_intfdata(interface);
1486         int minor = interface->minor;
1487         int i;
1488
1489         usb_set_intfdata(interface, NULL);      /*  remove the pdx from the interface */
1490         usb_deregister_dev(interface, &ced_class);      /*  give back our minor device number */
1491
1492         mutex_lock(&pdx->io_mutex);     /*  stop more I/O starting while... */
1493         ced_draw_down(pdx);     /*  ...wait for then kill any io */
1494         for (i = 0; i < MAX_TRANSAREAS; ++i) {
1495                 int iErr = ClearArea(pdx, i);   /*  ...release any used memory */
1496                 if (iErr == U14ERR_UNLOCKFAIL)
1497                         dev_err(&pdx->interface->dev, "%s Area %d was in used",
1498                                 __func__, i);
1499         }
1500         pdx->interface = NULL;  /*  ...we kill off link to interface */
1501         mutex_unlock(&pdx->io_mutex);
1502
1503         usb_kill_anchored_urbs(&pdx->submitted);
1504
1505         kref_put(&pdx->kref, ced_delete);       /*  decrement our usage count */
1506
1507         dev_info(&interface->dev, "USB cedusb #%d now disconnected", minor);
1508 }
1509
1510 /*  Wait for all the urbs we know of to be done with, then kill off any that */
1511 /*  are left. NBNB we will need to have a mechanism to stop circular xfers */
1512 /*  from trying to fire off more urbs. We will wait up to 3 seconds for Urbs */
1513 /*  to be done. */
1514 void ced_draw_down(DEVICE_EXTENSION *pdx)
1515 {
1516         int time;
1517         dev_dbg(&pdx->interface->dev, "%s called", __func__);
1518
1519         pdx->bInDrawDown = true;
1520         time = usb_wait_anchor_empty_timeout(&pdx->submitted, 3000);
1521         if (!time) {            /*  if we timed out we kill the urbs */
1522                 usb_kill_anchored_urbs(&pdx->submitted);
1523                 dev_err(&pdx->interface->dev, "%s timed out", __func__);
1524         }
1525         pdx->bInDrawDown = false;
1526 }
1527
1528 static int ced_suspend(struct usb_interface *intf, pm_message_t message)
1529 {
1530         DEVICE_EXTENSION *pdx = usb_get_intfdata(intf);
1531         if (!pdx)
1532                 return 0;
1533         ced_draw_down(pdx);
1534
1535         dev_dbg(&pdx->interface->dev, "%s called", __func__);
1536         return 0;
1537 }
1538
1539 static int ced_resume(struct usb_interface *intf)
1540 {
1541         DEVICE_EXTENSION *pdx = usb_get_intfdata(intf);
1542         if (!pdx)
1543                 return 0;
1544         dev_dbg(&pdx->interface->dev, "%s called", __func__);
1545         return 0;
1546 }
1547
1548 static int ced_pre_reset(struct usb_interface *intf)
1549 {
1550         DEVICE_EXTENSION *pdx = usb_get_intfdata(intf);
1551         dev_dbg(&pdx->interface->dev, "%s", __func__);
1552         mutex_lock(&pdx->io_mutex);
1553         ced_draw_down(pdx);
1554         return 0;
1555 }
1556
1557 static int ced_post_reset(struct usb_interface *intf)
1558 {
1559         DEVICE_EXTENSION *pdx = usb_get_intfdata(intf);
1560         dev_dbg(&pdx->interface->dev, "%s", __func__);
1561
1562         /* we are sure no URBs are active - no locking needed */
1563         pdx->errors = -EPIPE;
1564         mutex_unlock(&pdx->io_mutex);
1565
1566         return 0;
1567 }
1568
1569 static struct usb_driver ced_driver = {
1570         .name = "cedusb",
1571         .probe = ced_probe,
1572         .disconnect = ced_disconnect,
1573         .suspend = ced_suspend,
1574         .resume = ced_resume,
1575         .pre_reset = ced_pre_reset,
1576         .post_reset = ced_post_reset,
1577         .id_table = ced_table,
1578         .supports_autosuspend = 1,
1579 };
1580
1581 module_usb_driver(ced_driver);
1582 MODULE_LICENSE("GPL");