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