SAFE public projects git trees. - safe/jmp/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         { USB_DEVICE(0x13b1, 0x001e), .driver_info = DEVICE_ZD1211 },
  56         /* ZD1211B */
  57         { USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
  58         { USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
  59         { USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
  60         { USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
  61         { USB_DEVICE(0x050d, 0x705c), .driver_info = DEVICE_ZD1211B },
  62         { USB_DEVICE(0x083a, 0x4505), .driver_info = DEVICE_ZD1211B },
  63         { USB_DEVICE(0x0471, 0x1236), .driver_info = DEVICE_ZD1211B },
  64         { USB_DEVICE(0x13b1, 0x0024), .driver_info = DEVICE_ZD1211B },
  65         { USB_DEVICE(0x0586, 0x340f), .driver_info = DEVICE_ZD1211B },
  66         { USB_DEVICE(0x0b05, 0x171b), .driver_info = DEVICE_ZD1211B },
  67         { USB_DEVICE(0x0586, 0x3410), .driver_info = DEVICE_ZD1211B },
  68         { USB_DEVICE(0x0baf, 0x0121), .driver_info = DEVICE_ZD1211B },
  69         { USB_DEVICE(0x0586, 0x3412), .driver_info = DEVICE_ZD1211B },
  70         /* "Driverless" devices that need ejecting */
  71         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
  72         {}
  73 };
  74
  75 MODULE_LICENSE("GPL");
  76 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
  77 MODULE_AUTHOR("Ulrich Kunitz");
  78 MODULE_AUTHOR("Daniel Drake");
  79 MODULE_VERSION("1.0");
  80 MODULE_DEVICE_TABLE(usb, usb_ids);
  81
  82 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
  83 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
  84
  85 /* USB device initialization */
  86
  87 static int request_fw_file(
  88         const struct firmware **fw, const char *name, struct device *device)
  89 {
  90         int r;
  91
  92         dev_dbg_f(device, "fw name %s\n", name);
  93
  94         r = request_firmware(fw, name, device);
  95         if (r)
  96                 dev_err(device,
  97                        "Could not load firmware file %s. Error number %d\n",
  98                        name, r);
  99         return r;
 100 }
 101
 102 static inline u16 get_bcdDevice(const struct usb_device *udev)
 103 {
 104         return le16_to_cpu(udev->descriptor.bcdDevice);
 105 }
 106
 107 enum upload_code_flags {
 108         REBOOT = 1,
 109 };
 110
 111 /* Ensures that MAX_TRANSFER_SIZE is even. */
 112 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
 113
 114 static int upload_code(struct usb_device *udev,
 115         const u8 *data, size_t size, u16 code_offset, int flags)
 116 {
 117         u8 *p;
 118         int r;
 119
 120         /* USB request blocks need "kmalloced" buffers.
 121          */
 122         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
 123         if (!p) {
 124                 dev_err(&udev->dev, "out of memory\n");
 125                 r = -ENOMEM;
 126                 goto error;
 127         }
 128
 129         size &= ~1;
 130         while (size > 0) {
 131                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
 132                         size : MAX_TRANSFER_SIZE;
 133
 134                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
 135
 136                 memcpy(p, data, transfer_size);
 137                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 138                         USB_REQ_FIRMWARE_DOWNLOAD,
 139                         USB_DIR_OUT | USB_TYPE_VENDOR,
 140                         code_offset, 0, p, transfer_size, 1000 /* ms */);
 141                 if (r < 0) {
 142                         dev_err(&udev->dev,
 143                                "USB control request for firmware upload"
 144                                " failed. Error number %d\n", r);
 145                         goto error;
 146                 }
 147                 transfer_size = r & ~1;
 148
 149                 size -= transfer_size;
 150                 data += transfer_size;
 151                 code_offset += transfer_size/sizeof(u16);
 152         }
 153
 154         if (flags & REBOOT) {
 155                 u8 ret;
 156
 157                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 158                         USB_REQ_FIRMWARE_CONFIRM,
 159                         USB_DIR_IN | USB_TYPE_VENDOR,
 160                         0, 0, &ret, sizeof(ret), 5000 /* ms */);
 161                 if (r != sizeof(ret)) {
 162                         dev_err(&udev->dev,
 163                                 "control request firmeware confirmation failed."
 164                                 " Return value %d\n", r);
 165                         if (r >= 0)
 166                                 r = -ENODEV;
 167                         goto error;
 168                 }
 169                 if (ret & 0x80) {
 170                         dev_err(&udev->dev,
 171                                 "Internal error while downloading."
 172                                 " Firmware confirm return value %#04x\n",
 173                                 (unsigned int)ret);
 174                         r = -ENODEV;
 175                         goto error;
 176                 }
 177                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
 178                         (unsigned int)ret);
 179         }
 180
 181         r = 0;
 182 error:
 183         kfree(p);
 184         return r;
 185 }
 186
 187 static u16 get_word(const void *data, u16 offset)
 188 {
 189         const __le16 *p = data;
 190         return le16_to_cpu(p[offset]);
 191 }
 192
 193 static char *get_fw_name(char *buffer, size_t size, u8 device_type,
 194                        const char* postfix)
 195 {
 196         scnprintf(buffer, size, "%s%s",
 197                 device_type == DEVICE_ZD1211B ?
 198                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
 199                 postfix);
 200         return buffer;
 201 }
 202
 203 static int handle_version_mismatch(struct usb_device *udev, u8 device_type,
 204         const struct firmware *ub_fw)
 205 {
 206         const struct firmware *ur_fw = NULL;
 207         int offset;
 208         int r = 0;
 209         char fw_name[128];
 210
 211         r = request_fw_file(&ur_fw,
 212                 get_fw_name(fw_name, sizeof(fw_name), device_type, "ur"),
 213                 &udev->dev);
 214         if (r)
 215                 goto error;
 216
 217         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START, REBOOT);
 218         if (r)
 219                 goto error;
 220
 221         offset = (E2P_BOOT_CODE_OFFSET * sizeof(u16));
 222         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
 223                 E2P_START + E2P_BOOT_CODE_OFFSET, REBOOT);
 224
 225         /* At this point, the vendor driver downloads the whole firmware
 226          * image, hacks around with version IDs, and uploads it again,
 227          * completely overwriting the boot code. We do not do this here as
 228          * it is not required on any tested devices, and it is suspected to
 229          * cause problems. */
 230 error:
 231         release_firmware(ur_fw);
 232         return r;
 233 }
 234
 235 static int upload_firmware(struct usb_device *udev, u8 device_type)
 236 {
 237         int r;
 238         u16 fw_bcdDevice;
 239         u16 bcdDevice;
 240         const struct firmware *ub_fw = NULL;
 241         const struct firmware *uph_fw = NULL;
 242         char fw_name[128];
 243
 244         bcdDevice = get_bcdDevice(udev);
 245
 246         r = request_fw_file(&ub_fw,
 247                 get_fw_name(fw_name, sizeof(fw_name), device_type,  "ub"),
 248                 &udev->dev);
 249         if (r)
 250                 goto error;
 251
 252         fw_bcdDevice = get_word(ub_fw->data, E2P_DATA_OFFSET);
 253
 254         if (fw_bcdDevice != bcdDevice) {
 255                 dev_info(&udev->dev,
 256                         "firmware version %#06x and device bootcode version "
 257                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
 258                 if (bcdDevice <= 0x4313)
 259                         dev_warn(&udev->dev, "device has old bootcode, please "
 260                                 "report success or failure\n");
 261
 262                 r = handle_version_mismatch(udev, device_type, ub_fw);
 263                 if (r)
 264                         goto error;
 265         } else {
 266                 dev_dbg_f(&udev->dev,
 267                         "firmware device id %#06x is equal to the "
 268                         "actual device id\n", fw_bcdDevice);
 269         }
 270
 271
 272         r = request_fw_file(&uph_fw,
 273                 get_fw_name(fw_name, sizeof(fw_name), device_type, "uphr"),
 274                 &udev->dev);
 275         if (r)
 276                 goto error;
 277
 278         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START, REBOOT);
 279         if (r) {
 280                 dev_err(&udev->dev,
 281                         "Could not upload firmware code uph. Error number %d\n",
 282                         r);
 283         }
 284
 285         /* FALL-THROUGH */
 286 error:
 287         release_firmware(ub_fw);
 288         release_firmware(uph_fw);
 289         return r;
 290 }
 291
 292 #define urb_dev(urb) (&(urb)->dev->dev)
 293
 294 static inline void handle_regs_int(struct urb *urb)
 295 {
 296         struct zd_usb *usb = urb->context;
 297         struct zd_usb_interrupt *intr = &usb->intr;
 298         int len;
 299
 300         ZD_ASSERT(in_interrupt());
 301         spin_lock(&intr->lock);
 302
 303         if (intr->read_regs_enabled) {
 304                 intr->read_regs.length = len = urb->actual_length;
 305
 306                 if (len > sizeof(intr->read_regs.buffer))
 307                         len = sizeof(intr->read_regs.buffer);
 308                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
 309                 intr->read_regs_enabled = 0;
 310                 complete(&intr->read_regs.completion);
 311                 goto out;
 312         }
 313
 314         dev_dbg_f(urb_dev(urb), "regs interrupt ignored\n");
 315 out:
 316         spin_unlock(&intr->lock);
 317 }
 318
 319 static inline void handle_retry_failed_int(struct urb *urb)
 320 {
 321         struct zd_usb *usb = urb->context;
 322         struct zd_mac *mac = zd_usb_to_mac(usb);
 323         struct ieee80211_device *ieee = zd_mac_to_ieee80211(mac);
 324
 325         ieee->stats.tx_errors++;
 326         ieee->ieee_stats.tx_retry_limit_exceeded++;
 327         dev_dbg_f(urb_dev(urb), "retry failed interrupt\n");
 328 }
 329
 330
 331 static void int_urb_complete(struct urb *urb)
 332 {
 333         int r;
 334         struct usb_int_header *hdr;
 335
 336         switch (urb->status) {
 337         case 0:
 338                 break;
 339         case -ESHUTDOWN:
 340         case -EINVAL:
 341         case -ENODEV:
 342         case -ENOENT:
 343         case -ECONNRESET:
 344         case -EPIPE:
 345                 goto kfree;
 346         default:
 347                 goto resubmit;
 348         }
 349
 350         if (urb->actual_length < sizeof(hdr)) {
 351                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
 352                 goto resubmit;
 353         }
 354
 355         hdr = urb->transfer_buffer;
 356         if (hdr->type != USB_INT_TYPE) {
 357                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
 358                 goto resubmit;
 359         }
 360
 361         switch (hdr->id) {
 362         case USB_INT_ID_REGS:
 363                 handle_regs_int(urb);
 364                 break;
 365         case USB_INT_ID_RETRY_FAILED:
 366                 handle_retry_failed_int(urb);
 367                 break;
 368         default:
 369                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
 370                         (unsigned int)hdr->id);
 371                 goto resubmit;
 372         }
 373
 374 resubmit:
 375         r = usb_submit_urb(urb, GFP_ATOMIC);
 376         if (r) {
 377                 dev_dbg_f(urb_dev(urb), "resubmit urb %p\n", urb);
 378                 goto kfree;
 379         }
 380         return;
 381 kfree:
 382         kfree(urb->transfer_buffer);
 383 }
 384
 385 static inline int int_urb_interval(struct usb_device *udev)
 386 {
 387         switch (udev->speed) {
 388         case USB_SPEED_HIGH:
 389                 return 4;
 390         case USB_SPEED_LOW:
 391                 return 10;
 392         case USB_SPEED_FULL:
 393         default:
 394                 return 1;
 395         }
 396 }
 397
 398 static inline int usb_int_enabled(struct zd_usb *usb)
 399 {
 400         unsigned long flags;
 401         struct zd_usb_interrupt *intr = &usb->intr;
 402         struct urb *urb;
 403
 404         spin_lock_irqsave(&intr->lock, flags);
 405         urb = intr->urb;
 406         spin_unlock_irqrestore(&intr->lock, flags);
 407         return urb != NULL;
 408 }
 409
 410 int zd_usb_enable_int(struct zd_usb *usb)
 411 {
 412         int r;
 413         struct usb_device *udev;
 414         struct zd_usb_interrupt *intr = &usb->intr;
 415         void *transfer_buffer = NULL;
 416         struct urb *urb;
 417
 418         dev_dbg_f(zd_usb_dev(usb), "\n");
 419
 420         urb = usb_alloc_urb(0, GFP_KERNEL);
 421         if (!urb) {
 422                 r = -ENOMEM;
 423                 goto out;
 424         }
 425
 426         ZD_ASSERT(!irqs_disabled());
 427         spin_lock_irq(&intr->lock);
 428         if (intr->urb) {
 429                 spin_unlock_irq(&intr->lock);
 430                 r = 0;
 431                 goto error_free_urb;
 432         }
 433         intr->urb = urb;
 434         spin_unlock_irq(&intr->lock);
 435
 436         /* TODO: make it a DMA buffer */
 437         r = -ENOMEM;
 438         transfer_buffer = kmalloc(USB_MAX_EP_INT_BUFFER, GFP_KERNEL);
 439         if (!transfer_buffer) {
 440                 dev_dbg_f(zd_usb_dev(usb),
 441                         "couldn't allocate transfer_buffer\n");
 442                 goto error_set_urb_null;
 443         }
 444
 445         udev = zd_usb_to_usbdev(usb);
 446         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
 447                          transfer_buffer, USB_MAX_EP_INT_BUFFER,
 448                          int_urb_complete, usb,
 449                          intr->interval);
 450
 451         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
 452         r = usb_submit_urb(urb, GFP_KERNEL);
 453         if (r) {
 454                 dev_dbg_f(zd_usb_dev(usb),
 455                          "Couldn't submit urb. Error number %d\n", r);
 456                 goto error;
 457         }
 458
 459         return 0;
 460 error:
 461         kfree(transfer_buffer);
 462 error_set_urb_null:
 463         spin_lock_irq(&intr->lock);
 464         intr->urb = NULL;
 465         spin_unlock_irq(&intr->lock);
 466 error_free_urb:
 467         usb_free_urb(urb);
 468 out:
 469         return r;
 470 }
 471
 472 void zd_usb_disable_int(struct zd_usb *usb)
 473 {
 474         unsigned long flags;
 475         struct zd_usb_interrupt *intr = &usb->intr;
 476         struct urb *urb;
 477
 478         spin_lock_irqsave(&intr->lock, flags);
 479         urb = intr->urb;
 480         if (!urb) {
 481                 spin_unlock_irqrestore(&intr->lock, flags);
 482                 return;
 483         }
 484         intr->urb = NULL;
 485         spin_unlock_irqrestore(&intr->lock, flags);
 486
 487         usb_kill_urb(urb);
 488         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
 489         usb_free_urb(urb);
 490 }
 491
 492 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
 493                              unsigned int length)
 494 {
 495         int i;
 496         struct zd_mac *mac = zd_usb_to_mac(usb);
 497         const struct rx_length_info *length_info;
 498
 499         if (length < sizeof(struct rx_length_info)) {
 500                 /* It's not a complete packet anyhow. */
 501                 struct ieee80211_device *ieee = zd_mac_to_ieee80211(mac);
 502                 ieee->stats.rx_errors++;
 503                 ieee->stats.rx_length_errors++;
 504                 return;
 505         }
 506         length_info = (struct rx_length_info *)
 507                 (buffer + length - sizeof(struct rx_length_info));
 508
 509         /* It might be that three frames are merged into a single URB
 510          * transaction. We have to check for the length info tag.
 511          *
 512          * While testing we discovered that length_info might be unaligned,
 513          * because if USB transactions are merged, the last packet will not
 514          * be padded. Unaligned access might also happen if the length_info
 515          * structure is not present.
 516          */
 517         if (get_unaligned(&length_info->tag) == cpu_to_le16(RX_LENGTH_INFO_TAG))
 518         {
 519                 unsigned int l, k, n;
 520                 for (i = 0, l = 0;; i++) {
 521                         k = le16_to_cpu(get_unaligned(&length_info->length[i]));
 522                         if (k == 0)
 523                                 return;
 524                         n = l+k;
 525                         if (n > length)
 526                                 return;
 527                         zd_mac_rx_irq(mac, buffer+l, k);
 528                         if (i >= 2)
 529                                 return;
 530                         l = (n+3) & ~3;
 531                 }
 532         } else {
 533                 zd_mac_rx_irq(mac, buffer, length);
 534         }
 535 }
 536
 537 static void rx_urb_complete(struct urb *urb)
 538 {
 539         struct zd_usb *usb;
 540         struct zd_usb_rx *rx;
 541         const u8 *buffer;
 542         unsigned int length;
 543
 544         switch (urb->status) {
 545         case 0:
 546                 break;
 547         case -ESHUTDOWN:
 548         case -EINVAL:
 549         case -ENODEV:
 550         case -ENOENT:
 551         case -ECONNRESET:
 552         case -EPIPE:
 553                 return;
 554         default:
 555                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 556                 goto resubmit;
 557         }
 558
 559         buffer = urb->transfer_buffer;
 560         length = urb->actual_length;
 561         usb = urb->context;
 562         rx = &usb->rx;
 563
 564         if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
 565                 /* If there is an old first fragment, we don't care. */
 566                 dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
 567                 ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
 568                 spin_lock(&rx->lock);
 569                 memcpy(rx->fragment, buffer, length);
 570                 rx->fragment_length = length;
 571                 spin_unlock(&rx->lock);
 572                 goto resubmit;
 573         }
 574
 575         spin_lock(&rx->lock);
 576         if (rx->fragment_length > 0) {
 577                 /* We are on a second fragment, we believe */
 578                 ZD_ASSERT(length + rx->fragment_length <=
 579                           ARRAY_SIZE(rx->fragment));
 580                 dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
 581                 memcpy(rx->fragment+rx->fragment_length, buffer, length);
 582                 handle_rx_packet(usb, rx->fragment,
 583                                  rx->fragment_length + length);
 584                 rx->fragment_length = 0;
 585                 spin_unlock(&rx->lock);
 586         } else {
 587                 spin_unlock(&rx->lock);
 588                 handle_rx_packet(usb, buffer, length);
 589         }
 590
 591 resubmit:
 592         usb_submit_urb(urb, GFP_ATOMIC);
 593 }
 594
 595 static struct urb *alloc_urb(struct zd_usb *usb)
 596 {
 597         struct usb_device *udev = zd_usb_to_usbdev(usb);
 598         struct urb *urb;
 599         void *buffer;
 600
 601         urb = usb_alloc_urb(0, GFP_KERNEL);
 602         if (!urb)
 603                 return NULL;
 604         buffer = usb_buffer_alloc(udev, USB_MAX_RX_SIZE, GFP_KERNEL,
 605                                   &urb->transfer_dma);
 606         if (!buffer) {
 607                 usb_free_urb(urb);
 608                 return NULL;
 609         }
 610
 611         usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
 612                           buffer, USB_MAX_RX_SIZE,
 613                           rx_urb_complete, usb);
 614         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 615
 616         return urb;
 617 }
 618
 619 static void free_urb(struct urb *urb)
 620 {
 621         if (!urb)
 622                 return;
 623         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 624                         urb->transfer_buffer, urb->transfer_dma);
 625         usb_free_urb(urb);
 626 }
 627
 628 int zd_usb_enable_rx(struct zd_usb *usb)
 629 {
 630         int i, r;
 631         struct zd_usb_rx *rx = &usb->rx;
 632         struct urb **urbs;
 633
 634         dev_dbg_f(zd_usb_dev(usb), "\n");
 635
 636         r = -ENOMEM;
 637         urbs = kcalloc(URBS_COUNT, sizeof(struct urb *), GFP_KERNEL);
 638         if (!urbs)
 639                 goto error;
 640         for (i = 0; i < URBS_COUNT; i++) {
 641                 urbs[i] = alloc_urb(usb);
 642                 if (!urbs[i])
 643                         goto error;
 644         }
 645
 646         ZD_ASSERT(!irqs_disabled());
 647         spin_lock_irq(&rx->lock);
 648         if (rx->urbs) {
 649                 spin_unlock_irq(&rx->lock);
 650                 r = 0;
 651                 goto error;
 652         }
 653         rx->urbs = urbs;
 654         rx->urbs_count = URBS_COUNT;
 655         spin_unlock_irq(&rx->lock);
 656
 657         for (i = 0; i < URBS_COUNT; i++) {
 658                 r = usb_submit_urb(urbs[i], GFP_KERNEL);
 659                 if (r)
 660                         goto error_submit;
 661         }
 662
 663         return 0;
 664 error_submit:
 665         for (i = 0; i < URBS_COUNT; i++) {
 666                 usb_kill_urb(urbs[i]);
 667         }
 668         spin_lock_irq(&rx->lock);
 669         rx->urbs = NULL;
 670         rx->urbs_count = 0;
 671         spin_unlock_irq(&rx->lock);
 672 error:
 673         if (urbs) {
 674                 for (i = 0; i < URBS_COUNT; i++)
 675                         free_urb(urbs[i]);
 676         }
 677         return r;
 678 }
 679
 680 void zd_usb_disable_rx(struct zd_usb *usb)
 681 {
 682         int i;
 683         unsigned long flags;
 684         struct urb **urbs;
 685         unsigned int count;
 686         struct zd_usb_rx *rx = &usb->rx;
 687
 688         spin_lock_irqsave(&rx->lock, flags);
 689         urbs = rx->urbs;
 690         count = rx->urbs_count;
 691         spin_unlock_irqrestore(&rx->lock, flags);
 692         if (!urbs)
 693                 return;
 694
 695         for (i = 0; i < count; i++) {
 696                 usb_kill_urb(urbs[i]);
 697                 free_urb(urbs[i]);
 698         }
 699         kfree(urbs);
 700
 701         spin_lock_irqsave(&rx->lock, flags);
 702         rx->urbs = NULL;
 703         rx->urbs_count = 0;
 704         spin_unlock_irqrestore(&rx->lock, flags);
 705 }
 706
 707 static void tx_urb_complete(struct urb *urb)
 708 {
 709         int r;
 710
 711         switch (urb->status) {
 712         case 0:
 713                 break;
 714         case -ESHUTDOWN:
 715         case -EINVAL:
 716         case -ENODEV:
 717         case -ENOENT:
 718         case -ECONNRESET:
 719         case -EPIPE:
 720                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 721                 break;
 722         default:
 723                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 724                 goto resubmit;
 725         }
 726 free_urb:
 727         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 728                         urb->transfer_buffer, urb->transfer_dma);
 729         usb_free_urb(urb);
 730         return;
 731 resubmit:
 732         r = usb_submit_urb(urb, GFP_ATOMIC);
 733         if (r) {
 734                 dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
 735                 goto free_urb;
 736         }
 737 }
 738
 739 /* Puts the frame on the USB endpoint. It doesn't wait for
 740  * completion. The frame must contain the control set.
 741  */
 742 int zd_usb_tx(struct zd_usb *usb, const u8 *frame, unsigned int length)
 743 {
 744         int r;
 745         struct usb_device *udev = zd_usb_to_usbdev(usb);
 746         struct urb *urb;
 747         void *buffer;
 748
 749         urb = usb_alloc_urb(0, GFP_ATOMIC);
 750         if (!urb) {
 751                 r = -ENOMEM;
 752                 goto out;
 753         }
 754
 755         buffer = usb_buffer_alloc(zd_usb_to_usbdev(usb), length, GFP_ATOMIC,
 756                                   &urb->transfer_dma);
 757         if (!buffer) {
 758                 r = -ENOMEM;
 759                 goto error_free_urb;
 760         }
 761         memcpy(buffer, frame, length);
 762
 763         usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
 764                           buffer, length, tx_urb_complete, NULL);
 765         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 766
 767         r = usb_submit_urb(urb, GFP_ATOMIC);
 768         if (r)
 769                 goto error;
 770         return 0;
 771 error:
 772         usb_buffer_free(zd_usb_to_usbdev(usb), length, buffer,
 773                         urb->transfer_dma);
 774 error_free_urb:
 775         usb_free_urb(urb);
 776 out:
 777         return r;
 778 }
 779
 780 static inline void init_usb_interrupt(struct zd_usb *usb)
 781 {
 782         struct zd_usb_interrupt *intr = &usb->intr;
 783
 784         spin_lock_init(&intr->lock);
 785         intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
 786         init_completion(&intr->read_regs.completion);
 787         intr->read_regs.cr_int_addr = cpu_to_le16((u16)CR_INTERRUPT);
 788 }
 789
 790 static inline void init_usb_rx(struct zd_usb *usb)
 791 {
 792         struct zd_usb_rx *rx = &usb->rx;
 793         spin_lock_init(&rx->lock);
 794         if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
 795                 rx->usb_packet_size = 512;
 796         } else {
 797                 rx->usb_packet_size = 64;
 798         }
 799         ZD_ASSERT(rx->fragment_length == 0);
 800 }
 801
 802 static inline void init_usb_tx(struct zd_usb *usb)
 803 {
 804         /* FIXME: at this point we will allocate a fixed number of urb's for
 805          * use in a cyclic scheme */
 806 }
 807
 808 void zd_usb_init(struct zd_usb *usb, struct net_device *netdev,
 809                  struct usb_interface *intf)
 810 {
 811         memset(usb, 0, sizeof(*usb));
 812         usb->intf = usb_get_intf(intf);
 813         usb_set_intfdata(usb->intf, netdev);
 814         init_usb_interrupt(usb);
 815         init_usb_tx(usb);
 816         init_usb_rx(usb);
 817 }
 818
 819 void zd_usb_clear(struct zd_usb *usb)
 820 {
 821         usb_set_intfdata(usb->intf, NULL);
 822         usb_put_intf(usb->intf);
 823         ZD_MEMCLEAR(usb, sizeof(*usb));
 824         /* FIXME: usb_interrupt, usb_tx, usb_rx? */
 825 }
 826
 827 static const char *speed(enum usb_device_speed speed)
 828 {
 829         switch (speed) {
 830         case USB_SPEED_LOW:
 831                 return "low";
 832         case USB_SPEED_FULL:
 833                 return "full";
 834         case USB_SPEED_HIGH:
 835                 return "high";
 836         default:
 837                 return "unknown speed";
 838         }
 839 }
 840
 841 static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
 842 {
 843         return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
 844                 le16_to_cpu(udev->descriptor.idVendor),
 845                 le16_to_cpu(udev->descriptor.idProduct),
 846                 get_bcdDevice(udev),
 847                 speed(udev->speed));
 848 }
 849
 850 int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
 851 {
 852         struct usb_device *udev = interface_to_usbdev(usb->intf);
 853         return scnprint_id(udev, buffer, size);
 854 }
 855
 856 #ifdef DEBUG
 857 static void print_id(struct usb_device *udev)
 858 {
 859         char buffer[40];
 860
 861         scnprint_id(udev, buffer, sizeof(buffer));
 862         buffer[sizeof(buffer)-1] = 0;
 863         dev_dbg_f(&udev->dev, "%s\n", buffer);
 864 }
 865 #else
 866 #define print_id(udev) do { } while (0)
 867 #endif
 868
 869 static int eject_installer(struct usb_interface *intf)
 870 {
 871         struct usb_device *udev = interface_to_usbdev(intf);
 872         struct usb_host_interface *iface_desc = &intf->altsetting[0];
 873         struct usb_endpoint_descriptor *endpoint;
 874         unsigned char *cmd;
 875         u8 bulk_out_ep;
 876         int r;
 877
 878         /* Find bulk out endpoint */
 879         endpoint = &iface_desc->endpoint[1].desc;
 880         if ((endpoint->bEndpointAddress & USB_TYPE_MASK) == USB_DIR_OUT &&
 881             (endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
 882             USB_ENDPOINT_XFER_BULK) {
 883                 bulk_out_ep = endpoint->bEndpointAddress;
 884         } else {
 885                 dev_err(&udev->dev,
 886                         "zd1211rw: Could not find bulk out endpoint\n");
 887                 return -ENODEV;
 888         }
 889
 890         cmd = kzalloc(31, GFP_KERNEL);
 891         if (cmd == NULL)
 892                 return -ENODEV;
 893
 894         /* USB bulk command block */
 895         cmd[0] = 0x55;  /* bulk command signature */
 896         cmd[1] = 0x53;  /* bulk command signature */
 897         cmd[2] = 0x42;  /* bulk command signature */
 898         cmd[3] = 0x43;  /* bulk command signature */
 899         cmd[14] = 6;    /* command length */
 900
 901         cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
 902         cmd[19] = 0x2;  /* eject disc */
 903
 904         dev_info(&udev->dev, "Ejecting virtual installer media...\n");
 905         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
 906                 cmd, 31, NULL, 2000);
 907         kfree(cmd);
 908         if (r)
 909                 return r;
 910
 911         /* At this point, the device disconnects and reconnects with the real
 912          * ID numbers. */
 913
 914         usb_set_intfdata(intf, NULL);
 915         return 0;
 916 }
 917
 918 static int probe(struct usb_interface *intf, const struct usb_device_id *id)
 919 {
 920         int r;
 921         struct usb_device *udev = interface_to_usbdev(intf);
 922         struct net_device *netdev = NULL;
 923
 924         print_id(udev);
 925
 926         if (id->driver_info & DEVICE_INSTALLER)
 927                 return eject_installer(intf);
 928
 929         switch (udev->speed) {
 930         case USB_SPEED_LOW:
 931         case USB_SPEED_FULL:
 932         case USB_SPEED_HIGH:
 933                 break;
 934         default:
 935                 dev_dbg_f(&intf->dev, "Unknown USB speed\n");
 936                 r = -ENODEV;
 937                 goto error;
 938         }
 939
 940         usb_reset_device(interface_to_usbdev(intf));
 941
 942         netdev = zd_netdev_alloc(intf);
 943         if (netdev == NULL) {
 944                 r = -ENOMEM;
 945                 goto error;
 946         }
 947
 948         r = upload_firmware(udev, id->driver_info);
 949         if (r) {
 950                 dev_err(&intf->dev,
 951                        "couldn't load firmware. Error number %d\n", r);
 952                 goto error;
 953         }
 954
 955         r = usb_reset_configuration(udev);
 956         if (r) {
 957                 dev_dbg_f(&intf->dev,
 958                         "couldn't reset configuration. Error number %d\n", r);
 959                 goto error;
 960         }
 961
 962         /* At this point the interrupt endpoint is not generally enabled. We
 963          * save the USB bandwidth until the network device is opened. But
 964          * notify that the initialization of the MAC will require the
 965          * interrupts to be temporary enabled.
 966          */
 967         r = zd_mac_init_hw(zd_netdev_mac(netdev), id->driver_info);
 968         if (r) {
 969                 dev_dbg_f(&intf->dev,
 970                          "couldn't initialize mac. Error number %d\n", r);
 971                 goto error;
 972         }
 973
 974         r = register_netdev(netdev);
 975         if (r) {
 976                 dev_dbg_f(&intf->dev,
 977                          "couldn't register netdev. Error number %d\n", r);
 978                 goto error;
 979         }
 980
 981         dev_dbg_f(&intf->dev, "successful\n");
 982         dev_info(&intf->dev,"%s\n", netdev->name);
 983         return 0;
 984 error:
 985         usb_reset_device(interface_to_usbdev(intf));
 986         zd_netdev_free(netdev);
 987         return r;
 988 }
 989
 990 static void disconnect(struct usb_interface *intf)
 991 {
 992         struct net_device *netdev = zd_intf_to_netdev(intf);
 993         struct zd_mac *mac = zd_netdev_mac(netdev);
 994         struct zd_usb *usb = &mac->chip.usb;
 995
 996         /* Either something really bad happened, or we're just dealing with
 997          * a DEVICE_INSTALLER. */
 998         if (netdev == NULL)
 999                 return;
1000
1001         dev_dbg_f(zd_usb_dev(usb), "\n");
1002
1003         zd_netdev_disconnect(netdev);
1004
1005         /* Just in case something has gone wrong! */
1006         zd_usb_disable_rx(usb);
1007         zd_usb_disable_int(usb);
1008
1009         /* If the disconnect has been caused by a removal of the
1010          * driver module, the reset allows reloading of the driver. If the
1011          * reset will not be executed here, the upload of the firmware in the
1012          * probe function caused by the reloading of the driver will fail.
1013          */
1014         usb_reset_device(interface_to_usbdev(intf));
1015
1016         zd_netdev_free(netdev);
1017         dev_dbg(&intf->dev, "disconnected\n");
1018 }
1019
1020 static struct usb_driver driver = {
1021         .name           = "zd1211rw",
1022         .id_table       = usb_ids,
1023         .probe          = probe,
1024         .disconnect     = disconnect,
1025 };
1026
1027 struct workqueue_struct *zd_workqueue;
1028
1029 static int __init usb_init(void)
1030 {
1031         int r;
1032
1033         pr_debug("%s usb_init()\n", driver.name);
1034
1035         zd_workqueue = create_singlethread_workqueue(driver.name);
1036         if (zd_workqueue == NULL) {
1037                 printk(KERN_ERR "%s couldn't create workqueue\n", driver.name);
1038                 return -ENOMEM;
1039         }
1040
1041         r = usb_register(&driver);
1042         if (r) {
1043                 destroy_workqueue(zd_workqueue);
1044                 printk(KERN_ERR "%s usb_register() failed. Error number %d\n",
1045                        driver.name, r);
1046                 return r;
1047         }
1048
1049         pr_debug("%s initialized\n", driver.name);
1050         return 0;
1051 }
1052
1053 static void __exit usb_exit(void)
1054 {
1055         pr_debug("%s usb_exit()\n", driver.name);
1056         usb_deregister(&driver);
1057         destroy_workqueue(zd_workqueue);
1058 }
1059
1060 module_init(usb_init);
1061 module_exit(usb_exit);
1062
1063 static int usb_int_regs_length(unsigned int count)
1064 {
1065         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1066 }
1067
1068 static void prepare_read_regs_int(struct zd_usb *usb)
1069 {
1070         struct zd_usb_interrupt *intr = &usb->intr;
1071
1072         spin_lock_irq(&intr->lock);
1073         intr->read_regs_enabled = 1;
1074         INIT_COMPLETION(intr->read_regs.completion);
1075         spin_unlock_irq(&intr->lock);
1076 }
1077
1078 static void disable_read_regs_int(struct zd_usb *usb)
1079 {
1080         struct zd_usb_interrupt *intr = &usb->intr;
1081
1082         spin_lock_irq(&intr->lock);
1083         intr->read_regs_enabled = 0;
1084         spin_unlock_irq(&intr->lock);
1085 }
1086
1087 static int get_results(struct zd_usb *usb, u16 *values,
1088                        struct usb_req_read_regs *req, unsigned int count)
1089 {
1090         int r;
1091         int i;
1092         struct zd_usb_interrupt *intr = &usb->intr;
1093         struct read_regs_int *rr = &intr->read_regs;
1094         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1095
1096         spin_lock_irq(&intr->lock);
1097
1098         r = -EIO;
1099         /* The created block size seems to be larger than expected.
1100          * However results appear to be correct.
1101          */
1102         if (rr->length < usb_int_regs_length(count)) {
1103                 dev_dbg_f(zd_usb_dev(usb),
1104                          "error: actual length %d less than expected %d\n",
1105                          rr->length, usb_int_regs_length(count));
1106                 goto error_unlock;
1107         }
1108         if (rr->length > sizeof(rr->buffer)) {
1109                 dev_dbg_f(zd_usb_dev(usb),
1110                          "error: actual length %d exceeds buffer size %zu\n",
1111                          rr->length, sizeof(rr->buffer));
1112                 goto error_unlock;
1113         }
1114
1115         for (i = 0; i < count; i++) {
1116                 struct reg_data *rd = &regs->regs[i];
1117                 if (rd->addr != req->addr[i]) {
1118                         dev_dbg_f(zd_usb_dev(usb),
1119                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1120                                  le16_to_cpu(rd->addr),
1121                                  le16_to_cpu(req->addr[i]));
1122                         goto error_unlock;
1123                 }
1124                 values[i] = le16_to_cpu(rd->value);
1125         }
1126
1127         r = 0;
1128 error_unlock:
1129         spin_unlock_irq(&intr->lock);
1130         return r;
1131 }
1132
1133 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1134                      const zd_addr_t *addresses, unsigned int count)
1135 {
1136         int r;
1137         int i, req_len, actual_req_len;
1138         struct usb_device *udev;
1139         struct usb_req_read_regs *req = NULL;
1140         unsigned long timeout;
1141
1142         if (count < 1) {
1143                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1144                 return -EINVAL;
1145         }
1146         if (count > USB_MAX_IOREAD16_COUNT) {
1147                 dev_dbg_f(zd_usb_dev(usb),
1148                          "error: count %u exceeds possible max %u\n",
1149                          count, USB_MAX_IOREAD16_COUNT);
1150                 return -EINVAL;
1151         }
1152         if (in_atomic()) {
1153                 dev_dbg_f(zd_usb_dev(usb),
1154                          "error: io in atomic context not supported\n");
1155                 return -EWOULDBLOCK;
1156         }
1157         if (!usb_int_enabled(usb)) {
1158                  dev_dbg_f(zd_usb_dev(usb),
1159                           "error: usb interrupt not enabled\n");
1160                 return -EWOULDBLOCK;
1161         }
1162
1163         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1164         req = kmalloc(req_len, GFP_KERNEL);
1165         if (!req)
1166                 return -ENOMEM;
1167         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1168         for (i = 0; i < count; i++)
1169                 req->addr[i] = cpu_to_le16((u16)addresses[i]);
1170
1171         udev = zd_usb_to_usbdev(usb);
1172         prepare_read_regs_int(usb);
1173         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1174                          req, req_len, &actual_req_len, 1000 /* ms */);
1175         if (r) {
1176                 dev_dbg_f(zd_usb_dev(usb),
1177                         "error in usb_bulk_msg(). Error number %d\n", r);
1178                 goto error;
1179         }
1180         if (req_len != actual_req_len) {
1181                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()\n"
1182                         " req_len %d != actual_req_len %d\n",
1183                         req_len, actual_req_len);
1184                 r = -EIO;
1185                 goto error;
1186         }
1187
1188         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1189                                               msecs_to_jiffies(1000));
1190         if (!timeout) {
1191                 disable_read_regs_int(usb);
1192                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1193                 r = -ETIMEDOUT;
1194                 goto error;
1195         }
1196
1197         r = get_results(usb, values, req, count);
1198 error:
1199         kfree(req);
1200         return r;
1201 }
1202
1203 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1204                       unsigned int count)
1205 {
1206         int r;
1207         struct usb_device *udev;
1208         struct usb_req_write_regs *req = NULL;
1209         int i, req_len, actual_req_len;
1210
1211         if (count == 0)
1212                 return 0;
1213         if (count > USB_MAX_IOWRITE16_COUNT) {
1214                 dev_dbg_f(zd_usb_dev(usb),
1215                         "error: count %u exceeds possible max %u\n",
1216                         count, USB_MAX_IOWRITE16_COUNT);
1217                 return -EINVAL;
1218         }
1219         if (in_atomic()) {
1220                 dev_dbg_f(zd_usb_dev(usb),
1221                         "error: io in atomic context not supported\n");
1222                 return -EWOULDBLOCK;
1223         }
1224
1225         req_len = sizeof(struct usb_req_write_regs) +
1226                   count * sizeof(struct reg_data);
1227         req = kmalloc(req_len, GFP_KERNEL);
1228         if (!req)
1229                 return -ENOMEM;
1230
1231         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1232         for (i = 0; i < count; i++) {
1233                 struct reg_data *rw  = &req->reg_writes[i];
1234                 rw->addr = cpu_to_le16((u16)ioreqs[i].addr);
1235                 rw->value = cpu_to_le16(ioreqs[i].value);
1236         }
1237
1238         udev = zd_usb_to_usbdev(usb);
1239         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1240                          req, req_len, &actual_req_len, 1000 /* ms */);
1241         if (r) {
1242                 dev_dbg_f(zd_usb_dev(usb),
1243                         "error in usb_bulk_msg(). Error number %d\n", r);
1244                 goto error;
1245         }
1246         if (req_len != actual_req_len) {
1247                 dev_dbg_f(zd_usb_dev(usb),
1248                         "error in usb_bulk_msg()"
1249                         " req_len %d != actual_req_len %d\n",
1250                         req_len, actual_req_len);
1251                 r = -EIO;
1252                 goto error;
1253         }
1254
1255         /* FALL-THROUGH with r == 0 */
1256 error:
1257         kfree(req);
1258         return r;
1259 }
1260
1261 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1262 {
1263         int r;
1264         struct usb_device *udev;
1265         struct usb_req_rfwrite *req = NULL;
1266         int i, req_len, actual_req_len;
1267         u16 bit_value_template;
1268
1269         if (in_atomic()) {
1270                 dev_dbg_f(zd_usb_dev(usb),
1271                         "error: io in atomic context not supported\n");
1272                 return -EWOULDBLOCK;
1273         }
1274         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1275                 dev_dbg_f(zd_usb_dev(usb),
1276                         "error: bits %d are smaller than"
1277                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1278                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1279                 return -EINVAL;
1280         }
1281         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1282                 dev_dbg_f(zd_usb_dev(usb),
1283                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1284                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1285                 return -EINVAL;
1286         }
1287 #ifdef DEBUG
1288         if (value & (~0UL << bits)) {
1289                 dev_dbg_f(zd_usb_dev(usb),
1290                         "error: value %#09x has bits >= %d set\n",
1291                         value, bits);
1292                 return -EINVAL;
1293         }
1294 #endif /* DEBUG */
1295
1296         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1297
1298         r = zd_usb_ioread16(usb, &bit_value_template, CR203);
1299         if (r) {
1300                 dev_dbg_f(zd_usb_dev(usb),
1301                         "error %d: Couldn't read CR203\n", r);
1302                 goto out;
1303         }
1304         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1305
1306         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1307         req = kmalloc(req_len, GFP_KERNEL);
1308         if (!req)
1309                 return -ENOMEM;
1310
1311         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1312         /* 1: 3683a, but not used in ZYDAS driver */
1313         req->value = cpu_to_le16(2);
1314         req->bits = cpu_to_le16(bits);
1315
1316         for (i = 0; i < bits; i++) {
1317                 u16 bv = bit_value_template;
1318                 if (value & (1 << (bits-1-i)))
1319                         bv |= RF_DATA;
1320                 req->bit_values[i] = cpu_to_le16(bv);
1321         }
1322
1323         udev = zd_usb_to_usbdev(usb);
1324         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1325                          req, req_len, &actual_req_len, 1000 /* ms */);
1326         if (r) {
1327                 dev_dbg_f(zd_usb_dev(usb),
1328                         "error in usb_bulk_msg(). Error number %d\n", r);
1329                 goto out;
1330         }
1331         if (req_len != actual_req_len) {
1332                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()"
1333                         " req_len %d != actual_req_len %d\n",
1334                         req_len, actual_req_len);
1335                 r = -EIO;
1336                 goto out;
1337         }
1338
1339         /* FALL-THROUGH with r == 0 */
1340 out:
1341         kfree(req);
1342         return r;
1343 }