err.no Git - linux-2.6/blob - drivers/net/wireless/zd1211rw/zd_usb.c

   1 /* zd_usb.c
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  16  */
  17
  18 #include <asm/unaligned.h>
  19 #include <linux/kernel.h>
  20 #include <linux/init.h>
  21 #include <linux/module.h>
  22 #include <linux/firmware.h>
  23 #include <linux/device.h>
  24 #include <linux/errno.h>
  25 #include <linux/skbuff.h>
  26 #include <linux/usb.h>
  27 #include <linux/workqueue.h>
  28 #include <net/ieee80211.h>
  29
  30 #include "zd_def.h"
  31 #include "zd_netdev.h"
  32 #include "zd_mac.h"
  33 #include "zd_usb.h"
  34 #include "zd_util.h"
  35
  36 static struct usb_device_id usb_ids[] = {
  37         /* ZD1211 */
  38         { USB_DEVICE(0x0ace, 0x1211), .driver_info = DEVICE_ZD1211 },
  39         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211 },
  40         { USB_DEVICE(0x126f, 0xa006), .driver_info = DEVICE_ZD1211 },
  41         { USB_DEVICE(0x6891, 0xa727), .driver_info = DEVICE_ZD1211 },
  42         { USB_DEVICE(0x0df6, 0x9071), .driver_info = DEVICE_ZD1211 },
  43         { USB_DEVICE(0x157e, 0x300b), .driver_info = DEVICE_ZD1211 },
  44         { USB_DEVICE(0x079b, 0x004a), .driver_info = DEVICE_ZD1211 },
  45         { USB_DEVICE(0x1740, 0x2000), .driver_info = DEVICE_ZD1211 },
  46         { USB_DEVICE(0x157e, 0x3204), .driver_info = DEVICE_ZD1211 },
  47         { USB_DEVICE(0x0586, 0x3402), .driver_info = DEVICE_ZD1211 },
  48         { USB_DEVICE(0x0b3b, 0x5630), .driver_info = DEVICE_ZD1211 },
  49         { USB_DEVICE(0x0b05, 0x170c), .driver_info = DEVICE_ZD1211 },
  50         { USB_DEVICE(0x1435, 0x0711), .driver_info = DEVICE_ZD1211 },
  51         { USB_DEVICE(0x0586, 0x3409), .driver_info = DEVICE_ZD1211 },
  52         { USB_DEVICE(0x0b3b, 0x1630), .driver_info = DEVICE_ZD1211 },
  53         { USB_DEVICE(0x0586, 0x3401), .driver_info = DEVICE_ZD1211 },
  54         { USB_DEVICE(0x14ea, 0xab13), .driver_info = DEVICE_ZD1211 },
  55         /* ZD1211B */
  56         { USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
  57         { USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
  58         { USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
  59         { USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
  60         { USB_DEVICE(0x050d, 0x705c), .driver_info = DEVICE_ZD1211B },
  61         { USB_DEVICE(0x083a, 0x4505), .driver_info = DEVICE_ZD1211B },
  62         { USB_DEVICE(0x0471, 0x1236), .driver_info = DEVICE_ZD1211B },
  63         /* "Driverless" devices that need ejecting */
  64         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
  65         {}
  66 };
  67
  68 MODULE_LICENSE("GPL");
  69 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
  70 MODULE_AUTHOR("Ulrich Kunitz");
  71 MODULE_AUTHOR("Daniel Drake");
  72 MODULE_VERSION("1.0");
  73 MODULE_DEVICE_TABLE(usb, usb_ids);
  74
  75 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
  76 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
  77
  78 /* USB device initialization */
  79
  80 static int request_fw_file(
  81         const struct firmware **fw, const char *name, struct device *device)
  82 {
  83         int r;
  84
  85         dev_dbg_f(device, "fw name %s\n", name);
  86
  87         r = request_firmware(fw, name, device);
  88         if (r)
  89                 dev_err(device,
  90                        "Could not load firmware file %s. Error number %d\n",
  91                        name, r);
  92         return r;
  93 }
  94
  95 static inline u16 get_bcdDevice(const struct usb_device *udev)
  96 {
  97         return le16_to_cpu(udev->descriptor.bcdDevice);
  98 }
  99
 100 enum upload_code_flags {
 101         REBOOT = 1,
 102 };
 103
 104 /* Ensures that MAX_TRANSFER_SIZE is even. */
 105 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
 106
 107 static int upload_code(struct usb_device *udev,
 108         const u8 *data, size_t size, u16 code_offset, int flags)
 109 {
 110         u8 *p;
 111         int r;
 112
 113         /* USB request blocks need "kmalloced" buffers.
 114          */
 115         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
 116         if (!p) {
 117                 dev_err(&udev->dev, "out of memory\n");
 118                 r = -ENOMEM;
 119                 goto error;
 120         }
 121
 122         size &= ~1;
 123         while (size > 0) {
 124                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
 125                         size : MAX_TRANSFER_SIZE;
 126
 127                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
 128
 129                 memcpy(p, data, transfer_size);
 130                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 131                         USB_REQ_FIRMWARE_DOWNLOAD,
 132                         USB_DIR_OUT | USB_TYPE_VENDOR,
 133                         code_offset, 0, p, transfer_size, 1000 /* ms */);
 134                 if (r < 0) {
 135                         dev_err(&udev->dev,
 136                                "USB control request for firmware upload"
 137                                " failed. Error number %d\n", r);
 138                         goto error;
 139                 }
 140                 transfer_size = r & ~1;
 141
 142                 size -= transfer_size;
 143                 data += transfer_size;
 144                 code_offset += transfer_size/sizeof(u16);
 145         }
 146
 147         if (flags & REBOOT) {
 148                 u8 ret;
 149
 150                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 151                         USB_REQ_FIRMWARE_CONFIRM,
 152                         USB_DIR_IN | USB_TYPE_VENDOR,
 153                         0, 0, &ret, sizeof(ret), 5000 /* ms */);
 154                 if (r != sizeof(ret)) {
 155                         dev_err(&udev->dev,
 156                                 "control request firmeware confirmation failed."
 157                                 " Return value %d\n", r);
 158                         if (r >= 0)
 159                                 r = -ENODEV;
 160                         goto error;
 161                 }
 162                 if (ret & 0x80) {
 163                         dev_err(&udev->dev,
 164                                 "Internal error while downloading."
 165                                 " Firmware confirm return value %#04x\n",
 166                                 (unsigned int)ret);
 167                         r = -ENODEV;
 168                         goto error;
 169                 }
 170                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
 171                         (unsigned int)ret);
 172         }
 173
 174         r = 0;
 175 error:
 176         kfree(p);
 177         return r;
 178 }
 179
 180 static u16 get_word(const void *data, u16 offset)
 181 {
 182         const __le16 *p = data;
 183         return le16_to_cpu(p[offset]);
 184 }
 185
 186 static char *get_fw_name(char *buffer, size_t size, u8 device_type,
 187                        const char* postfix)
 188 {
 189         scnprintf(buffer, size, "%s%s",
 190                 device_type == DEVICE_ZD1211B ?
 191                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
 192                 postfix);
 193         return buffer;
 194 }
 195
 196 static int handle_version_mismatch(struct usb_device *udev, u8 device_type,
 197         const struct firmware *ub_fw)
 198 {
 199         const struct firmware *ur_fw = NULL;
 200         int offset;
 201         int r = 0;
 202         char fw_name[128];
 203
 204         r = request_fw_file(&ur_fw,
 205                 get_fw_name(fw_name, sizeof(fw_name), device_type, "ur"),
 206                 &udev->dev);
 207         if (r)
 208                 goto error;
 209
 210         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START, REBOOT);
 211         if (r)
 212                 goto error;
 213
 214         offset = (E2P_BOOT_CODE_OFFSET * sizeof(u16));
 215         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
 216                 E2P_START + E2P_BOOT_CODE_OFFSET, REBOOT);
 217
 218         /* At this point, the vendor driver downloads the whole firmware
 219          * image, hacks around with version IDs, and uploads it again,
 220          * completely overwriting the boot code. We do not do this here as
 221          * it is not required on any tested devices, and it is suspected to
 222          * cause problems. */
 223 error:
 224         release_firmware(ur_fw);
 225         return r;
 226 }
 227
 228 static int upload_firmware(struct usb_device *udev, u8 device_type)
 229 {
 230         int r;
 231         u16 fw_bcdDevice;
 232         u16 bcdDevice;
 233         const struct firmware *ub_fw = NULL;
 234         const struct firmware *uph_fw = NULL;
 235         char fw_name[128];
 236
 237         bcdDevice = get_bcdDevice(udev);
 238
 239         r = request_fw_file(&ub_fw,
 240                 get_fw_name(fw_name, sizeof(fw_name), device_type,  "ub"),
 241                 &udev->dev);
 242         if (r)
 243                 goto error;
 244
 245         fw_bcdDevice = get_word(ub_fw->data, E2P_DATA_OFFSET);
 246
 247         if (fw_bcdDevice != bcdDevice) {
 248                 dev_info(&udev->dev,
 249                         "firmware version %#06x and device bootcode version "
 250                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
 251                 if (bcdDevice <= 0x4313)
 252                         dev_warn(&udev->dev, "device has old bootcode, please "
 253                                 "report success or failure\n");
 254
 255                 r = handle_version_mismatch(udev, device_type, ub_fw);
 256                 if (r)
 257                         goto error;
 258         } else {
 259                 dev_dbg_f(&udev->dev,
 260                         "firmware device id %#06x is equal to the "
 261                         "actual device id\n", fw_bcdDevice);
 262         }
 263
 264
 265         r = request_fw_file(&uph_fw,
 266                 get_fw_name(fw_name, sizeof(fw_name), device_type, "uphr"),
 267                 &udev->dev);
 268         if (r)
 269                 goto error;
 270
 271         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START, REBOOT);
 272         if (r) {
 273                 dev_err(&udev->dev,
 274                         "Could not upload firmware code uph. Error number %d\n",
 275                         r);
 276         }
 277
 278         /* FALL-THROUGH */
 279 error:
 280         release_firmware(ub_fw);
 281         release_firmware(uph_fw);
 282         return r;
 283 }
 284
 285 #define urb_dev(urb) (&(urb)->dev->dev)
 286
 287 static inline void handle_regs_int(struct urb *urb)
 288 {
 289         struct zd_usb *usb = urb->context;
 290         struct zd_usb_interrupt *intr = &usb->intr;
 291         int len;
 292
 293         ZD_ASSERT(in_interrupt());
 294         spin_lock(&intr->lock);
 295
 296         if (intr->read_regs_enabled) {
 297                 intr->read_regs.length = len = urb->actual_length;
 298
 299                 if (len > sizeof(intr->read_regs.buffer))
 300                         len = sizeof(intr->read_regs.buffer);
 301                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
 302                 intr->read_regs_enabled = 0;
 303                 complete(&intr->read_regs.completion);
 304                 goto out;
 305         }
 306
 307         dev_dbg_f(urb_dev(urb), "regs interrupt ignored\n");
 308 out:
 309         spin_unlock(&intr->lock);
 310 }
 311
 312 static inline void handle_retry_failed_int(struct urb *urb)
 313 {
 314         dev_dbg_f(urb_dev(urb), "retry failed interrupt\n");
 315 }
 316
 317
 318 static void int_urb_complete(struct urb *urb)
 319 {
 320         int r;
 321         struct usb_int_header *hdr;
 322
 323         switch (urb->status) {
 324         case 0:
 325                 break;
 326         case -ESHUTDOWN:
 327         case -EINVAL:
 328         case -ENODEV:
 329         case -ENOENT:
 330         case -ECONNRESET:
 331         case -EPIPE:
 332                 goto kfree;
 333         default:
 334                 goto resubmit;
 335         }
 336
 337         if (urb->actual_length < sizeof(hdr)) {
 338                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
 339                 goto resubmit;
 340         }
 341
 342         hdr = urb->transfer_buffer;
 343         if (hdr->type != USB_INT_TYPE) {
 344                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
 345                 goto resubmit;
 346         }
 347
 348         switch (hdr->id) {
 349         case USB_INT_ID_REGS:
 350                 handle_regs_int(urb);
 351                 break;
 352         case USB_INT_ID_RETRY_FAILED:
 353                 handle_retry_failed_int(urb);
 354                 break;
 355         default:
 356                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
 357                         (unsigned int)hdr->id);
 358                 goto resubmit;
 359         }
 360
 361 resubmit:
 362         r = usb_submit_urb(urb, GFP_ATOMIC);
 363         if (r) {
 364                 dev_dbg_f(urb_dev(urb), "resubmit urb %p\n", urb);
 365                 goto kfree;
 366         }
 367         return;
 368 kfree:
 369         kfree(urb->transfer_buffer);
 370 }
 371
 372 static inline int int_urb_interval(struct usb_device *udev)
 373 {
 374         switch (udev->speed) {
 375         case USB_SPEED_HIGH:
 376                 return 4;
 377         case USB_SPEED_LOW:
 378                 return 10;
 379         case USB_SPEED_FULL:
 380         default:
 381                 return 1;
 382         }
 383 }
 384
 385 static inline int usb_int_enabled(struct zd_usb *usb)
 386 {
 387         unsigned long flags;
 388         struct zd_usb_interrupt *intr = &usb->intr;
 389         struct urb *urb;
 390
 391         spin_lock_irqsave(&intr->lock, flags);
 392         urb = intr->urb;
 393         spin_unlock_irqrestore(&intr->lock, flags);
 394         return urb != NULL;
 395 }
 396
 397 int zd_usb_enable_int(struct zd_usb *usb)
 398 {
 399         int r;
 400         struct usb_device *udev;
 401         struct zd_usb_interrupt *intr = &usb->intr;
 402         void *transfer_buffer = NULL;
 403         struct urb *urb;
 404
 405         dev_dbg_f(zd_usb_dev(usb), "\n");
 406
 407         urb = usb_alloc_urb(0, GFP_NOFS);
 408         if (!urb) {
 409                 r = -ENOMEM;
 410                 goto out;
 411         }
 412
 413         ZD_ASSERT(!irqs_disabled());
 414         spin_lock_irq(&intr->lock);
 415         if (intr->urb) {
 416                 spin_unlock_irq(&intr->lock);
 417                 r = 0;
 418                 goto error_free_urb;
 419         }
 420         intr->urb = urb;
 421         spin_unlock_irq(&intr->lock);
 422
 423         /* TODO: make it a DMA buffer */
 424         r = -ENOMEM;
 425         transfer_buffer = kmalloc(USB_MAX_EP_INT_BUFFER, GFP_NOFS);
 426         if (!transfer_buffer) {
 427                 dev_dbg_f(zd_usb_dev(usb),
 428                         "couldn't allocate transfer_buffer\n");
 429                 goto error_set_urb_null;
 430         }
 431
 432         udev = zd_usb_to_usbdev(usb);
 433         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
 434                          transfer_buffer, USB_MAX_EP_INT_BUFFER,
 435                          int_urb_complete, usb,
 436                          intr->interval);
 437
 438         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
 439         r = usb_submit_urb(urb, GFP_NOFS);
 440         if (r) {
 441                 dev_dbg_f(zd_usb_dev(usb),
 442                          "Couldn't submit urb. Error number %d\n", r);
 443                 goto error;
 444         }
 445
 446         return 0;
 447 error:
 448         kfree(transfer_buffer);
 449 error_set_urb_null:
 450         spin_lock_irq(&intr->lock);
 451         intr->urb = NULL;
 452         spin_unlock_irq(&intr->lock);
 453 error_free_urb:
 454         usb_free_urb(urb);
 455 out:
 456         return r;
 457 }
 458
 459 void zd_usb_disable_int(struct zd_usb *usb)
 460 {
 461         unsigned long flags;
 462         struct zd_usb_interrupt *intr = &usb->intr;
 463         struct urb *urb;
 464
 465         spin_lock_irqsave(&intr->lock, flags);
 466         urb = intr->urb;
 467         if (!urb) {
 468                 spin_unlock_irqrestore(&intr->lock, flags);
 469                 return;
 470         }
 471         intr->urb = NULL;
 472         spin_unlock_irqrestore(&intr->lock, flags);
 473
 474         usb_kill_urb(urb);
 475         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
 476         usb_free_urb(urb);
 477 }
 478
 479 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
 480                              unsigned int length)
 481 {
 482         int i;
 483         struct zd_mac *mac = zd_usb_to_mac(usb);
 484         const struct rx_length_info *length_info;
 485
 486         if (length < sizeof(struct rx_length_info)) {
 487                 /* It's not a complete packet anyhow. */
 488                 return;
 489         }
 490         length_info = (struct rx_length_info *)
 491                 (buffer + length - sizeof(struct rx_length_info));
 492
 493         /* It might be that three frames are merged into a single URB
 494          * transaction. We have to check for the length info tag.
 495          *
 496          * While testing we discovered that length_info might be unaligned,
 497          * because if USB transactions are merged, the last packet will not
 498          * be padded. Unaligned access might also happen if the length_info
 499          * structure is not present.
 500          */
 501         if (get_unaligned(&length_info->tag) == cpu_to_le16(RX_LENGTH_INFO_TAG))
 502         {
 503                 unsigned int l, k, n;
 504                 for (i = 0, l = 0;; i++) {
 505                         k = le16_to_cpu(get_unaligned(&length_info->length[i]));
 506                         if (k == 0)
 507                                 return;
 508                         n = l+k;
 509                         if (n > length)
 510                                 return;
 511                         zd_mac_rx_irq(mac, buffer+l, k);
 512                         if (i >= 2)
 513                                 return;
 514                         l = (n+3) & ~3;
 515                 }
 516         } else {
 517                 zd_mac_rx_irq(mac, buffer, length);
 518         }
 519 }
 520
 521 static void rx_urb_complete(struct urb *urb)
 522 {
 523         struct zd_usb *usb;
 524         struct zd_usb_rx *rx;
 525         const u8 *buffer;
 526         unsigned int length;
 527
 528         switch (urb->status) {
 529         case 0:
 530                 break;
 531         case -ESHUTDOWN:
 532         case -EINVAL:
 533         case -ENODEV:
 534         case -ENOENT:
 535         case -ECONNRESET:
 536         case -EPIPE:
 537                 return;
 538         default:
 539                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 540                 goto resubmit;
 541         }
 542
 543         buffer = urb->transfer_buffer;
 544         length = urb->actual_length;
 545         usb = urb->context;
 546         rx = &usb->rx;
 547
 548         if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
 549                 /* If there is an old first fragment, we don't care. */
 550                 dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
 551                 ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
 552                 spin_lock(&rx->lock);
 553                 memcpy(rx->fragment, buffer, length);
 554                 rx->fragment_length = length;
 555                 spin_unlock(&rx->lock);
 556                 goto resubmit;
 557         }
 558
 559         spin_lock(&rx->lock);
 560         if (rx->fragment_length > 0) {
 561                 /* We are on a second fragment, we believe */
 562                 ZD_ASSERT(length + rx->fragment_length <=
 563                           ARRAY_SIZE(rx->fragment));
 564                 dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
 565                 memcpy(rx->fragment+rx->fragment_length, buffer, length);
 566                 handle_rx_packet(usb, rx->fragment,
 567                                  rx->fragment_length + length);
 568                 rx->fragment_length = 0;
 569                 spin_unlock(&rx->lock);
 570         } else {
 571                 spin_unlock(&rx->lock);
 572                 handle_rx_packet(usb, buffer, length);
 573         }
 574
 575 resubmit:
 576         usb_submit_urb(urb, GFP_ATOMIC);
 577 }
 578
 579 static struct urb *alloc_urb(struct zd_usb *usb)
 580 {
 581         struct usb_device *udev = zd_usb_to_usbdev(usb);
 582         struct urb *urb;
 583         void *buffer;
 584
 585         urb = usb_alloc_urb(0, GFP_NOFS);
 586         if (!urb)
 587                 return NULL;
 588         buffer = usb_buffer_alloc(udev, USB_MAX_RX_SIZE, GFP_NOFS,
 589                                   &urb->transfer_dma);
 590         if (!buffer) {
 591                 usb_free_urb(urb);
 592                 return NULL;
 593         }
 594
 595         usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
 596                           buffer, USB_MAX_RX_SIZE,
 597                           rx_urb_complete, usb);
 598         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 599
 600         return urb;
 601 }
 602
 603 static void free_urb(struct urb *urb)
 604 {
 605         if (!urb)
 606                 return;
 607         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 608                         urb->transfer_buffer, urb->transfer_dma);
 609         usb_free_urb(urb);
 610 }
 611
 612 int zd_usb_enable_rx(struct zd_usb *usb)
 613 {
 614         int i, r;
 615         struct zd_usb_rx *rx = &usb->rx;
 616         struct urb **urbs;
 617
 618         dev_dbg_f(zd_usb_dev(usb), "\n");
 619
 620         r = -ENOMEM;
 621         urbs = kcalloc(URBS_COUNT, sizeof(struct urb *), GFP_NOFS);
 622         if (!urbs)
 623                 goto error;
 624         for (i = 0; i < URBS_COUNT; i++) {
 625                 urbs[i] = alloc_urb(usb);
 626                 if (!urbs[i])
 627                         goto error;
 628         }
 629
 630         ZD_ASSERT(!irqs_disabled());
 631         spin_lock_irq(&rx->lock);
 632         if (rx->urbs) {
 633                 spin_unlock_irq(&rx->lock);
 634                 r = 0;
 635                 goto error;
 636         }
 637         rx->urbs = urbs;
 638         rx->urbs_count = URBS_COUNT;
 639         spin_unlock_irq(&rx->lock);
 640
 641         for (i = 0; i < URBS_COUNT; i++) {
 642                 r = usb_submit_urb(urbs[i], GFP_NOFS);
 643                 if (r)
 644                         goto error_submit;
 645         }
 646
 647         return 0;
 648 error_submit:
 649         for (i = 0; i < URBS_COUNT; i++) {
 650                 usb_kill_urb(urbs[i]);
 651         }
 652         spin_lock_irq(&rx->lock);
 653         rx->urbs = NULL;
 654         rx->urbs_count = 0;
 655         spin_unlock_irq(&rx->lock);
 656 error:
 657         if (urbs) {
 658                 for (i = 0; i < URBS_COUNT; i++)
 659                         free_urb(urbs[i]);
 660         }
 661         return r;
 662 }
 663
 664 void zd_usb_disable_rx(struct zd_usb *usb)
 665 {
 666         int i;
 667         unsigned long flags;
 668         struct urb **urbs;
 669         unsigned int count;
 670         struct zd_usb_rx *rx = &usb->rx;
 671
 672         spin_lock_irqsave(&rx->lock, flags);
 673         urbs = rx->urbs;
 674         count = rx->urbs_count;
 675         spin_unlock_irqrestore(&rx->lock, flags);
 676         if (!urbs)
 677                 return;
 678
 679         for (i = 0; i < count; i++) {
 680                 usb_kill_urb(urbs[i]);
 681                 free_urb(urbs[i]);
 682         }
 683         kfree(urbs);
 684
 685         spin_lock_irqsave(&rx->lock, flags);
 686         rx->urbs = NULL;
 687         rx->urbs_count = 0;
 688         spin_unlock_irqrestore(&rx->lock, flags);
 689 }
 690
 691 static void tx_urb_complete(struct urb *urb)
 692 {
 693         int r;
 694
 695         switch (urb->status) {
 696         case 0:
 697                 break;
 698         case -ESHUTDOWN:
 699         case -EINVAL:
 700         case -ENODEV:
 701         case -ENOENT:
 702         case -ECONNRESET:
 703         case -EPIPE:
 704                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 705                 break;
 706         default:
 707                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 708                 goto resubmit;
 709         }
 710 free_urb:
 711         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 712                         urb->transfer_buffer, urb->transfer_dma);
 713         usb_free_urb(urb);
 714         return;
 715 resubmit:
 716         r = usb_submit_urb(urb, GFP_ATOMIC);
 717         if (r) {
 718                 dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
 719                 goto free_urb;
 720         }
 721 }
 722
 723 /* Puts the frame on the USB endpoint. It doesn't wait for
 724  * completion. The frame must contain the control set.
 725  */
 726 int zd_usb_tx(struct zd_usb *usb, const u8 *frame, unsigned int length)
 727 {
 728         int r;
 729         struct usb_device *udev = zd_usb_to_usbdev(usb);
 730         struct urb *urb;
 731         void *buffer;
 732
 733         urb = usb_alloc_urb(0, GFP_ATOMIC);
 734         if (!urb) {
 735                 r = -ENOMEM;
 736                 goto out;
 737         }
 738
 739         buffer = usb_buffer_alloc(zd_usb_to_usbdev(usb), length, GFP_ATOMIC,
 740                                   &urb->transfer_dma);
 741         if (!buffer) {
 742                 r = -ENOMEM;
 743                 goto error_free_urb;
 744         }
 745         memcpy(buffer, frame, length);
 746
 747         usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
 748                           buffer, length, tx_urb_complete, NULL);
 749         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 750
 751         r = usb_submit_urb(urb, GFP_ATOMIC);
 752         if (r)
 753                 goto error;
 754         return 0;
 755 error:
 756         usb_buffer_free(zd_usb_to_usbdev(usb), length, buffer,
 757                         urb->transfer_dma);
 758 error_free_urb:
 759         usb_free_urb(urb);
 760 out:
 761         return r;
 762 }
 763
 764 static inline void init_usb_interrupt(struct zd_usb *usb)
 765 {
 766         struct zd_usb_interrupt *intr = &usb->intr;
 767
 768         spin_lock_init(&intr->lock);
 769         intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
 770         init_completion(&intr->read_regs.completion);
 771         intr->read_regs.cr_int_addr = cpu_to_le16((u16)CR_INTERRUPT);
 772 }
 773
 774 static inline void init_usb_rx(struct zd_usb *usb)
 775 {
 776         struct zd_usb_rx *rx = &usb->rx;
 777         spin_lock_init(&rx->lock);
 778         if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
 779                 rx->usb_packet_size = 512;
 780         } else {
 781                 rx->usb_packet_size = 64;
 782         }
 783         ZD_ASSERT(rx->fragment_length == 0);
 784 }
 785
 786 static inline void init_usb_tx(struct zd_usb *usb)
 787 {
 788         /* FIXME: at this point we will allocate a fixed number of urb's for
 789          * use in a cyclic scheme */
 790 }
 791
 792 void zd_usb_init(struct zd_usb *usb, struct net_device *netdev,
 793                  struct usb_interface *intf)
 794 {
 795         memset(usb, 0, sizeof(*usb));
 796         usb->intf = usb_get_intf(intf);
 797         usb_set_intfdata(usb->intf, netdev);
 798         init_usb_interrupt(usb);
 799         init_usb_tx(usb);
 800         init_usb_rx(usb);
 801 }
 802
 803 void zd_usb_clear(struct zd_usb *usb)
 804 {
 805         usb_set_intfdata(usb->intf, NULL);
 806         usb_put_intf(usb->intf);
 807         ZD_MEMCLEAR(usb, sizeof(*usb));
 808         /* FIXME: usb_interrupt, usb_tx, usb_rx? */
 809 }
 810
 811 static const char *speed(enum usb_device_speed speed)
 812 {
 813         switch (speed) {
 814         case USB_SPEED_LOW:
 815                 return "low";
 816         case USB_SPEED_FULL:
 817                 return "full";
 818         case USB_SPEED_HIGH:
 819                 return "high";
 820         default:
 821                 return "unknown speed";
 822         }
 823 }
 824
 825 static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
 826 {
 827         return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
 828                 le16_to_cpu(udev->descriptor.idVendor),
 829                 le16_to_cpu(udev->descriptor.idProduct),
 830                 get_bcdDevice(udev),
 831                 speed(udev->speed));
 832 }
 833
 834 int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
 835 {
 836         struct usb_device *udev = interface_to_usbdev(usb->intf);
 837         return scnprint_id(udev, buffer, size);
 838 }
 839
 840 #ifdef DEBUG
 841 static void print_id(struct usb_device *udev)
 842 {
 843         char buffer[40];
 844
 845         scnprint_id(udev, buffer, sizeof(buffer));
 846         buffer[sizeof(buffer)-1] = 0;
 847         dev_dbg_f(&udev->dev, "%s\n", buffer);
 848 }
 849 #else
 850 #define print_id(udev) do { } while (0)
 851 #endif
 852
 853 static int eject_installer(struct usb_interface *intf)
 854 {
 855         struct usb_device *udev = interface_to_usbdev(intf);
 856         struct usb_host_interface *iface_desc = &intf->altsetting[0];
 857         struct usb_endpoint_descriptor *endpoint;
 858         unsigned char *cmd;
 859         u8 bulk_out_ep;
 860         int r;
 861
 862         /* Find bulk out endpoint */
 863         endpoint = &iface_desc->endpoint[1].desc;
 864         if ((endpoint->bEndpointAddress & USB_TYPE_MASK) == USB_DIR_OUT &&
 865             (endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
 866             USB_ENDPOINT_XFER_BULK) {
 867                 bulk_out_ep = endpoint->bEndpointAddress;
 868         } else {
 869                 dev_err(&udev->dev,
 870                         "zd1211rw: Could not find bulk out endpoint\n");
 871                 return -ENODEV;
 872         }
 873
 874         cmd = kzalloc(31, GFP_KERNEL);
 875         if (cmd == NULL)
 876                 return -ENODEV;
 877
 878         /* USB bulk command block */
 879         cmd[0] = 0x55;  /* bulk command signature */
 880         cmd[1] = 0x53;  /* bulk command signature */
 881         cmd[2] = 0x42;  /* bulk command signature */
 882         cmd[3] = 0x43;  /* bulk command signature */
 883         cmd[14] = 6;    /* command length */
 884
 885         cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
 886         cmd[19] = 0x2;  /* eject disc */
 887
 888         dev_info(&udev->dev, "Ejecting virtual installer media...\n");
 889         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
 890                 cmd, 31, NULL, 2000);
 891         kfree(cmd);
 892         if (r)
 893                 return r;
 894
 895         /* At this point, the device disconnects and reconnects with the real
 896          * ID numbers. */
 897
 898         usb_set_intfdata(intf, NULL);
 899         return 0;
 900 }
 901
 902 static int probe(struct usb_interface *intf, const struct usb_device_id *id)
 903 {
 904         int r;
 905         struct usb_device *udev = interface_to_usbdev(intf);
 906         struct net_device *netdev = NULL;
 907
 908         print_id(udev);
 909
 910         if (id->driver_info & DEVICE_INSTALLER)
 911                 return eject_installer(intf);
 912
 913         switch (udev->speed) {
 914         case USB_SPEED_LOW:
 915         case USB_SPEED_FULL:
 916         case USB_SPEED_HIGH:
 917                 break;
 918         default:
 919                 dev_dbg_f(&intf->dev, "Unknown USB speed\n");
 920                 r = -ENODEV;
 921                 goto error;
 922         }
 923
 924         netdev = zd_netdev_alloc(intf);
 925         if (netdev == NULL) {
 926                 r = -ENOMEM;
 927                 goto error;
 928         }
 929
 930         r = upload_firmware(udev, id->driver_info);
 931         if (r) {
 932                 dev_err(&intf->dev,
 933                        "couldn't load firmware. Error number %d\n", r);
 934                 goto error;
 935         }
 936
 937         r = usb_reset_configuration(udev);
 938         if (r) {
 939                 dev_dbg_f(&intf->dev,
 940                         "couldn't reset configuration. Error number %d\n", r);
 941                 goto error;
 942         }
 943
 944         /* At this point the interrupt endpoint is not generally enabled. We
 945          * save the USB bandwidth until the network device is opened. But
 946          * notify that the initialization of the MAC will require the
 947          * interrupts to be temporary enabled.
 948          */
 949         r = zd_mac_init_hw(zd_netdev_mac(netdev), id->driver_info);
 950         if (r) {
 951                 dev_dbg_f(&intf->dev,
 952                          "couldn't initialize mac. Error number %d\n", r);
 953                 goto error;
 954         }
 955
 956         r = register_netdev(netdev);
 957         if (r) {
 958                 dev_dbg_f(&intf->dev,
 959                          "couldn't register netdev. Error number %d\n", r);
 960                 goto error;
 961         }
 962
 963         dev_dbg_f(&intf->dev, "successful\n");
 964         dev_info(&intf->dev,"%s\n", netdev->name);
 965         return 0;
 966 error:
 967         usb_reset_device(interface_to_usbdev(intf));
 968         zd_netdev_free(netdev);
 969         return r;
 970 }
 971
 972 static void disconnect(struct usb_interface *intf)
 973 {
 974         struct net_device *netdev = zd_intf_to_netdev(intf);
 975         struct zd_mac *mac = zd_netdev_mac(netdev);
 976         struct zd_usb *usb = &mac->chip.usb;
 977
 978         /* Either something really bad happened, or we're just dealing with
 979          * a DEVICE_INSTALLER. */
 980         if (netdev == NULL)
 981                 return;
 982
 983         dev_dbg_f(zd_usb_dev(usb), "\n");
 984
 985         zd_netdev_disconnect(netdev);
 986
 987         /* Just in case something has gone wrong! */
 988         zd_usb_disable_rx(usb);
 989         zd_usb_disable_int(usb);
 990
 991         /* If the disconnect has been caused by a removal of the
 992          * driver module, the reset allows reloading of the driver. If the
 993          * reset will not be executed here, the upload of the firmware in the
 994          * probe function caused by the reloading of the driver will fail.
 995          */
 996         usb_reset_device(interface_to_usbdev(intf));
 997
 998         zd_netdev_free(netdev);
 999         dev_dbg(&intf->dev, "disconnected\n");
1000 }
1001
1002 static struct usb_driver driver = {
1003         .name           = "zd1211rw",
1004         .id_table       = usb_ids,
1005         .probe          = probe,
1006         .disconnect     = disconnect,
1007 };
1008
1009 struct workqueue_struct *zd_workqueue;
1010
1011 static int __init usb_init(void)
1012 {
1013         int r;
1014
1015         pr_debug("%s usb_init()\n", driver.name);
1016
1017         zd_workqueue = create_singlethread_workqueue(driver.name);
1018         if (zd_workqueue == NULL) {
1019                 printk(KERN_ERR "%s couldn't create workqueue\n", driver.name);
1020                 return -ENOMEM;
1021         }
1022
1023         r = usb_register(&driver);
1024         if (r) {
1025                 printk(KERN_ERR "%s usb_register() failed. Error number %d\n",
1026                        driver.name, r);
1027                 return r;
1028         }
1029
1030         pr_debug("%s initialized\n", driver.name);
1031         return 0;
1032 }
1033
1034 static void __exit usb_exit(void)
1035 {
1036         pr_debug("%s usb_exit()\n", driver.name);
1037         usb_deregister(&driver);
1038         destroy_workqueue(zd_workqueue);
1039 }
1040
1041 module_init(usb_init);
1042 module_exit(usb_exit);
1043
1044 static int usb_int_regs_length(unsigned int count)
1045 {
1046         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1047 }
1048
1049 static void prepare_read_regs_int(struct zd_usb *usb)
1050 {
1051         struct zd_usb_interrupt *intr = &usb->intr;
1052
1053         spin_lock_irq(&intr->lock);
1054         intr->read_regs_enabled = 1;
1055         INIT_COMPLETION(intr->read_regs.completion);
1056         spin_unlock_irq(&intr->lock);
1057 }
1058
1059 static void disable_read_regs_int(struct zd_usb *usb)
1060 {
1061         struct zd_usb_interrupt *intr = &usb->intr;
1062
1063         spin_lock_irq(&intr->lock);
1064         intr->read_regs_enabled = 0;
1065         spin_unlock_irq(&intr->lock);
1066 }
1067
1068 static int get_results(struct zd_usb *usb, u16 *values,
1069                        struct usb_req_read_regs *req, unsigned int count)
1070 {
1071         int r;
1072         int i;
1073         struct zd_usb_interrupt *intr = &usb->intr;
1074         struct read_regs_int *rr = &intr->read_regs;
1075         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1076
1077         spin_lock_irq(&intr->lock);
1078
1079         r = -EIO;
1080         /* The created block size seems to be larger than expected.
1081          * However results appear to be correct.
1082          */
1083         if (rr->length < usb_int_regs_length(count)) {
1084                 dev_dbg_f(zd_usb_dev(usb),
1085                          "error: actual length %d less than expected %d\n",
1086                          rr->length, usb_int_regs_length(count));
1087                 goto error_unlock;
1088         }
1089         if (rr->length > sizeof(rr->buffer)) {
1090                 dev_dbg_f(zd_usb_dev(usb),
1091                          "error: actual length %d exceeds buffer size %zu\n",
1092                          rr->length, sizeof(rr->buffer));
1093                 goto error_unlock;
1094         }
1095
1096         for (i = 0; i < count; i++) {
1097                 struct reg_data *rd = &regs->regs[i];
1098                 if (rd->addr != req->addr[i]) {
1099                         dev_dbg_f(zd_usb_dev(usb),
1100                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1101                                  le16_to_cpu(rd->addr),
1102                                  le16_to_cpu(req->addr[i]));
1103                         goto error_unlock;
1104                 }
1105                 values[i] = le16_to_cpu(rd->value);
1106         }
1107
1108         r = 0;
1109 error_unlock:
1110         spin_unlock_irq(&intr->lock);
1111         return r;
1112 }
1113
1114 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1115                      const zd_addr_t *addresses, unsigned int count)
1116 {
1117         int r;
1118         int i, req_len, actual_req_len;
1119         struct usb_device *udev;
1120         struct usb_req_read_regs *req = NULL;
1121         unsigned long timeout;
1122
1123         if (count < 1) {
1124                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1125                 return -EINVAL;
1126         }
1127         if (count > USB_MAX_IOREAD16_COUNT) {
1128                 dev_dbg_f(zd_usb_dev(usb),
1129                          "error: count %u exceeds possible max %u\n",
1130                          count, USB_MAX_IOREAD16_COUNT);
1131                 return -EINVAL;
1132         }
1133         if (in_atomic()) {
1134                 dev_dbg_f(zd_usb_dev(usb),
1135                          "error: io in atomic context not supported\n");
1136                 return -EWOULDBLOCK;
1137         }
1138         if (!usb_int_enabled(usb)) {
1139                  dev_dbg_f(zd_usb_dev(usb),
1140                           "error: usb interrupt not enabled\n");
1141                 return -EWOULDBLOCK;
1142         }
1143
1144         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1145         req = kmalloc(req_len, GFP_NOFS);
1146         if (!req)
1147                 return -ENOMEM;
1148         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1149         for (i = 0; i < count; i++)
1150                 req->addr[i] = cpu_to_le16((u16)addresses[i]);
1151
1152         udev = zd_usb_to_usbdev(usb);
1153         prepare_read_regs_int(usb);
1154         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1155                          req, req_len, &actual_req_len, 1000 /* ms */);
1156         if (r) {
1157                 dev_dbg_f(zd_usb_dev(usb),
1158                         "error in usb_bulk_msg(). Error number %d\n", r);
1159                 goto error;
1160         }
1161         if (req_len != actual_req_len) {
1162                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()\n"
1163                         " req_len %d != actual_req_len %d\n",
1164                         req_len, actual_req_len);
1165                 r = -EIO;
1166                 goto error;
1167         }
1168
1169         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1170                                               msecs_to_jiffies(1000));
1171         if (!timeout) {
1172                 disable_read_regs_int(usb);
1173                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1174                 r = -ETIMEDOUT;
1175                 goto error;
1176         }
1177
1178         r = get_results(usb, values, req, count);
1179 error:
1180         kfree(req);
1181         return r;
1182 }
1183
1184 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1185                       unsigned int count)
1186 {
1187         int r;
1188         struct usb_device *udev;
1189         struct usb_req_write_regs *req = NULL;
1190         int i, req_len, actual_req_len;
1191
1192         if (count == 0)
1193                 return 0;
1194         if (count > USB_MAX_IOWRITE16_COUNT) {
1195                 dev_dbg_f(zd_usb_dev(usb),
1196                         "error: count %u exceeds possible max %u\n",
1197                         count, USB_MAX_IOWRITE16_COUNT);
1198                 return -EINVAL;
1199         }
1200         if (in_atomic()) {
1201                 dev_dbg_f(zd_usb_dev(usb),
1202                         "error: io in atomic context not supported\n");
1203                 return -EWOULDBLOCK;
1204         }
1205
1206         req_len = sizeof(struct usb_req_write_regs) +
1207                   count * sizeof(struct reg_data);
1208         req = kmalloc(req_len, GFP_NOFS);
1209         if (!req)
1210                 return -ENOMEM;
1211
1212         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1213         for (i = 0; i < count; i++) {
1214                 struct reg_data *rw  = &req->reg_writes[i];
1215                 rw->addr = cpu_to_le16((u16)ioreqs[i].addr);
1216                 rw->value = cpu_to_le16(ioreqs[i].value);
1217         }
1218
1219         udev = zd_usb_to_usbdev(usb);
1220         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1221                          req, req_len, &actual_req_len, 1000 /* ms */);
1222         if (r) {
1223                 dev_dbg_f(zd_usb_dev(usb),
1224                         "error in usb_bulk_msg(). Error number %d\n", r);
1225                 goto error;
1226         }
1227         if (req_len != actual_req_len) {
1228                 dev_dbg_f(zd_usb_dev(usb),
1229                         "error in usb_bulk_msg()"
1230                         " req_len %d != actual_req_len %d\n",
1231                         req_len, actual_req_len);
1232                 r = -EIO;
1233                 goto error;
1234         }
1235
1236         /* FALL-THROUGH with r == 0 */
1237 error:
1238         kfree(req);
1239         return r;
1240 }
1241
1242 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1243 {
1244         int r;
1245         struct usb_device *udev;
1246         struct usb_req_rfwrite *req = NULL;
1247         int i, req_len, actual_req_len;
1248         u16 bit_value_template;
1249
1250         if (in_atomic()) {
1251                 dev_dbg_f(zd_usb_dev(usb),
1252                         "error: io in atomic context not supported\n");
1253                 return -EWOULDBLOCK;
1254         }
1255         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1256                 dev_dbg_f(zd_usb_dev(usb),
1257                         "error: bits %d are smaller than"
1258                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1259                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1260                 return -EINVAL;
1261         }
1262         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1263                 dev_dbg_f(zd_usb_dev(usb),
1264                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1265                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1266                 return -EINVAL;
1267         }
1268 #ifdef DEBUG
1269         if (value & (~0UL << bits)) {
1270                 dev_dbg_f(zd_usb_dev(usb),
1271                         "error: value %#09x has bits >= %d set\n",
1272                         value, bits);
1273                 return -EINVAL;
1274         }
1275 #endif /* DEBUG */
1276
1277         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1278
1279         r = zd_usb_ioread16(usb, &bit_value_template, CR203);
1280         if (r) {
1281                 dev_dbg_f(zd_usb_dev(usb),
1282                         "error %d: Couldn't read CR203\n", r);
1283                 goto out;
1284         }
1285         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1286
1287         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1288         req = kmalloc(req_len, GFP_NOFS);
1289         if (!req)
1290                 return -ENOMEM;
1291
1292         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1293         /* 1: 3683a, but not used in ZYDAS driver */
1294         req->value = cpu_to_le16(2);
1295         req->bits = cpu_to_le16(bits);
1296
1297         for (i = 0; i < bits; i++) {
1298                 u16 bv = bit_value_template;
1299                 if (value & (1 << (bits-1-i)))
1300                         bv |= RF_DATA;
1301                 req->bit_values[i] = cpu_to_le16(bv);
1302         }
1303
1304         udev = zd_usb_to_usbdev(usb);
1305         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1306                          req, req_len, &actual_req_len, 1000 /* ms */);
1307         if (r) {
1308                 dev_dbg_f(zd_usb_dev(usb),
1309                         "error in usb_bulk_msg(). Error number %d\n", r);
1310                 goto out;
1311         }
1312         if (req_len != actual_req_len) {
1313                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()"
1314                         " req_len %d != actual_req_len %d\n",
1315                         req_len, actual_req_len);
1316                 r = -EIO;
1317                 goto out;
1318         }
1319
1320         /* FALL-THROUGH with r == 0 */
1321 out:
1322         kfree(req);
1323         return r;
1324 }