drivers/net/wireless/zd1211rw/zd_usb.c

   1 /* zd_usb.c
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  16  */
  17
  18 #include <asm/unaligned.h>
  19 #include <linux/kernel.h>
  20 #include <linux/init.h>
  21 #include <linux/module.h>
  22 #include <linux/firmware.h>
  23 #include <linux/device.h>
  24 #include <linux/errno.h>
  25 #include <linux/skbuff.h>
  26 #include <linux/usb.h>
  27 #include <linux/workqueue.h>
  28 #include <net/ieee80211.h>
  29
  30 #include "zd_def.h"
  31 #include "zd_netdev.h"
  32 #include "zd_mac.h"
  33 #include "zd_usb.h"
  34 #include "zd_util.h"
  35
  36 static struct usb_device_id usb_ids[] = {
  37         /* ZD1211 */
  38         { USB_DEVICE(0x0ace, 0x1211), .driver_info = DEVICE_ZD1211 },
  39         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211 },
  40         { USB_DEVICE(0x126f, 0xa006), .driver_info = DEVICE_ZD1211 },
  41         { USB_DEVICE(0x6891, 0xa727), .driver_info = DEVICE_ZD1211 },
  42         { USB_DEVICE(0x0df6, 0x9071), .driver_info = DEVICE_ZD1211 },
  43         { USB_DEVICE(0x157e, 0x300b), .driver_info = DEVICE_ZD1211 },
  44         { USB_DEVICE(0x079b, 0x004a), .driver_info = DEVICE_ZD1211 },
  45         { USB_DEVICE(0x1740, 0x2000), .driver_info = DEVICE_ZD1211 },
  46         { USB_DEVICE(0x157e, 0x3204), .driver_info = DEVICE_ZD1211 },
  47         { USB_DEVICE(0x0586, 0x3402), .driver_info = DEVICE_ZD1211 },
  48         { USB_DEVICE(0x0b3b, 0x5630), .driver_info = DEVICE_ZD1211 },
  49         { USB_DEVICE(0x0b05, 0x170c), .driver_info = DEVICE_ZD1211 },
  50         { USB_DEVICE(0x1435, 0x0711), .driver_info = DEVICE_ZD1211 },
  51         { USB_DEVICE(0x0586, 0x3409), .driver_info = DEVICE_ZD1211 },
  52         { USB_DEVICE(0x0b3b, 0x1630), .driver_info = DEVICE_ZD1211 },
  53         { USB_DEVICE(0x0586, 0x3401), .driver_info = DEVICE_ZD1211 },
  54         { USB_DEVICE(0x14ea, 0xab13), .driver_info = DEVICE_ZD1211 },
  55         /* ZD1211B */
  56         { USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
  57         { USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
  58         { USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
  59         { USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
  60         { USB_DEVICE(0x050d, 0x705c), .driver_info = DEVICE_ZD1211B },
  61         { USB_DEVICE(0x083a, 0x4505), .driver_info = DEVICE_ZD1211B },
  62         { USB_DEVICE(0x0471, 0x1236), .driver_info = DEVICE_ZD1211B },
  63         { USB_DEVICE(0x13b1, 0x0024), .driver_info = DEVICE_ZD1211B },
  64         /* "Driverless" devices that need ejecting */
  65         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
  66         {}
  67 };
  68
  69 MODULE_LICENSE("GPL");
  70 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
  71 MODULE_AUTHOR("Ulrich Kunitz");
  72 MODULE_AUTHOR("Daniel Drake");
  73 MODULE_VERSION("1.0");
  74 MODULE_DEVICE_TABLE(usb, usb_ids);
  75
  76 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
  77 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
  78
  79 /* USB device initialization */
  80
  81 static int request_fw_file(
  82         const struct firmware **fw, const char *name, struct device *device)
  83 {
  84         int r;
  85
  86         dev_dbg_f(device, "fw name %s\n", name);
  87
  88         r = request_firmware(fw, name, device);
  89         if (r)
  90                 dev_err(device,
  91                        "Could not load firmware file %s. Error number %d\n",
  92                        name, r);
  93         return r;
  94 }
  95
  96 static inline u16 get_bcdDevice(const struct usb_device *udev)
  97 {
  98         return le16_to_cpu(udev->descriptor.bcdDevice);
  99 }
 100
 101 enum upload_code_flags {
 102         REBOOT = 1,
 103 };
 104
 105 /* Ensures that MAX_TRANSFER_SIZE is even. */
 106 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
 107
 108 static int upload_code(struct usb_device *udev,
 109         const u8 *data, size_t size, u16 code_offset, int flags)
 110 {
 111         u8 *p;
 112         int r;
 113
 114         /* USB request blocks need "kmalloced" buffers.
 115          */
 116         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
 117         if (!p) {
 118                 dev_err(&udev->dev, "out of memory\n");
 119                 r = -ENOMEM;
 120                 goto error;
 121         }
 122
 123         size &= ~1;
 124         while (size > 0) {
 125                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
 126                         size : MAX_TRANSFER_SIZE;
 127
 128                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
 129
 130                 memcpy(p, data, transfer_size);
 131                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 132                         USB_REQ_FIRMWARE_DOWNLOAD,
 133                         USB_DIR_OUT | USB_TYPE_VENDOR,
 134                         code_offset, 0, p, transfer_size, 1000 /* ms */);
 135                 if (r < 0) {
 136                         dev_err(&udev->dev,
 137                                "USB control request for firmware upload"
 138                                " failed. Error number %d\n", r);
 139                         goto error;
 140                 }
 141                 transfer_size = r & ~1;
 142
 143                 size -= transfer_size;
 144                 data += transfer_size;
 145                 code_offset += transfer_size/sizeof(u16);
 146         }
 147
 148         if (flags & REBOOT) {
 149                 u8 ret;
 150
 151                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 152                         USB_REQ_FIRMWARE_CONFIRM,
 153                         USB_DIR_IN | USB_TYPE_VENDOR,
 154                         0, 0, &ret, sizeof(ret), 5000 /* ms */);
 155                 if (r != sizeof(ret)) {
 156                         dev_err(&udev->dev,
 157                                 "control request firmeware confirmation failed."
 158                                 " Return value %d\n", r);
 159                         if (r >= 0)
 160                                 r = -ENODEV;
 161                         goto error;
 162                 }
 163                 if (ret & 0x80) {
 164                         dev_err(&udev->dev,
 165                                 "Internal error while downloading."
 166                                 " Firmware confirm return value %#04x\n",
 167                                 (unsigned int)ret);
 168                         r = -ENODEV;
 169                         goto error;
 170                 }
 171                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
 172                         (unsigned int)ret);
 173         }
 174
 175         r = 0;
 176 error:
 177         kfree(p);
 178         return r;
 179 }
 180
 181 static u16 get_word(const void *data, u16 offset)
 182 {
 183         const __le16 *p = data;
 184         return le16_to_cpu(p[offset]);
 185 }
 186
 187 static char *get_fw_name(char *buffer, size_t size, u8 device_type,
 188                        const char* postfix)
 189 {
 190         scnprintf(buffer, size, "%s%s",
 191                 device_type == DEVICE_ZD1211B ?
 192                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
 193                 postfix);
 194         return buffer;
 195 }
 196
 197 static int handle_version_mismatch(struct usb_device *udev, u8 device_type,
 198         const struct firmware *ub_fw)
 199 {
 200         const struct firmware *ur_fw = NULL;
 201         int offset;
 202         int r = 0;
 203         char fw_name[128];
 204
 205         r = request_fw_file(&ur_fw,
 206                 get_fw_name(fw_name, sizeof(fw_name), device_type, "ur"),
 207                 &udev->dev);
 208         if (r)
 209                 goto error;
 210
 211         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START, REBOOT);
 212         if (r)
 213                 goto error;
 214
 215         offset = (E2P_BOOT_CODE_OFFSET * sizeof(u16));
 216         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
 217                 E2P_START + E2P_BOOT_CODE_OFFSET, REBOOT);
 218
 219         /* At this point, the vendor driver downloads the whole firmware
 220          * image, hacks around with version IDs, and uploads it again,
 221          * completely overwriting the boot code. We do not do this here as
 222          * it is not required on any tested devices, and it is suspected to
 223          * cause problems. */
 224 error:
 225         release_firmware(ur_fw);
 226         return r;
 227 }
 228
 229 static int upload_firmware(struct usb_device *udev, u8 device_type)
 230 {
 231         int r;
 232         u16 fw_bcdDevice;
 233         u16 bcdDevice;
 234         const struct firmware *ub_fw = NULL;
 235         const struct firmware *uph_fw = NULL;
 236         char fw_name[128];
 237
 238         bcdDevice = get_bcdDevice(udev);
 239
 240         r = request_fw_file(&ub_fw,
 241                 get_fw_name(fw_name, sizeof(fw_name), device_type,  "ub"),
 242                 &udev->dev);
 243         if (r)
 244                 goto error;
 245
 246         fw_bcdDevice = get_word(ub_fw->data, E2P_DATA_OFFSET);
 247
 248         if (fw_bcdDevice != bcdDevice) {
 249                 dev_info(&udev->dev,
 250                         "firmware version %#06x and device bootcode version "
 251                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
 252                 if (bcdDevice <= 0x4313)
 253                         dev_warn(&udev->dev, "device has old bootcode, please "
 254                                 "report success or failure\n");
 255
 256                 r = handle_version_mismatch(udev, device_type, ub_fw);
 257                 if (r)
 258                         goto error;
 259         } else {
 260                 dev_dbg_f(&udev->dev,
 261                         "firmware device id %#06x is equal to the "
 262                         "actual device id\n", fw_bcdDevice);
 263         }
 264
 265
 266         r = request_fw_file(&uph_fw,
 267                 get_fw_name(fw_name, sizeof(fw_name), device_type, "uphr"),
 268                 &udev->dev);
 269         if (r)
 270                 goto error;
 271
 272         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START, REBOOT);
 273         if (r) {
 274                 dev_err(&udev->dev,
 275                         "Could not upload firmware code uph. Error number %d\n",
 276                         r);
 277         }
 278
 279         /* FALL-THROUGH */
 280 error:
 281         release_firmware(ub_fw);
 282         release_firmware(uph_fw);
 283         return r;
 284 }
 285
 286 #define urb_dev(urb) (&(urb)->dev->dev)
 287
 288 static inline void handle_regs_int(struct urb *urb)
 289 {
 290         struct zd_usb *usb = urb->context;
 291         struct zd_usb_interrupt *intr = &usb->intr;
 292         int len;
 293
 294         ZD_ASSERT(in_interrupt());
 295         spin_lock(&intr->lock);
 296
 297         if (intr->read_regs_enabled) {
 298                 intr->read_regs.length = len = urb->actual_length;
 299
 300                 if (len > sizeof(intr->read_regs.buffer))
 301                         len = sizeof(intr->read_regs.buffer);
 302                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
 303                 intr->read_regs_enabled = 0;
 304                 complete(&intr->read_regs.completion);
 305                 goto out;
 306         }
 307
 308         dev_dbg_f(urb_dev(urb), "regs interrupt ignored\n");
 309 out:
 310         spin_unlock(&intr->lock);
 311 }
 312
 313 static inline void handle_retry_failed_int(struct urb *urb)
 314 {
 315         dev_dbg_f(urb_dev(urb), "retry failed interrupt\n");
 316 }
 317
 318
 319 static void int_urb_complete(struct urb *urb)
 320 {
 321         int r;
 322         struct usb_int_header *hdr;
 323
 324         switch (urb->status) {
 325         case 0:
 326                 break;
 327         case -ESHUTDOWN:
 328         case -EINVAL:
 329         case -ENODEV:
 330         case -ENOENT:
 331         case -ECONNRESET:
 332         case -EPIPE:
 333                 goto kfree;
 334         default:
 335                 goto resubmit;
 336         }
 337
 338         if (urb->actual_length < sizeof(hdr)) {
 339                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
 340                 goto resubmit;
 341         }
 342
 343         hdr = urb->transfer_buffer;
 344         if (hdr->type != USB_INT_TYPE) {
 345                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
 346                 goto resubmit;
 347         }
 348
 349         switch (hdr->id) {
 350         case USB_INT_ID_REGS:
 351                 handle_regs_int(urb);
 352                 break;
 353         case USB_INT_ID_RETRY_FAILED:
 354                 handle_retry_failed_int(urb);
 355                 break;
 356         default:
 357                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
 358                         (unsigned int)hdr->id);
 359                 goto resubmit;
 360         }
 361
 362 resubmit:
 363         r = usb_submit_urb(urb, GFP_ATOMIC);
 364         if (r) {
 365                 dev_dbg_f(urb_dev(urb), "resubmit urb %p\n", urb);
 366                 goto kfree;
 367         }
 368         return;
 369 kfree:
 370         kfree(urb->transfer_buffer);
 371 }
 372
 373 static inline int int_urb_interval(struct usb_device *udev)
 374 {
 375         switch (udev->speed) {
 376         case USB_SPEED_HIGH:
 377                 return 4;
 378         case USB_SPEED_LOW:
 379                 return 10;
 380         case USB_SPEED_FULL:
 381         default:
 382                 return 1;
 383         }
 384 }
 385
 386 static inline int usb_int_enabled(struct zd_usb *usb)
 387 {
 388         unsigned long flags;
 389         struct zd_usb_interrupt *intr = &usb->intr;
 390         struct urb *urb;
 391
 392         spin_lock_irqsave(&intr->lock, flags);
 393         urb = intr->urb;
 394         spin_unlock_irqrestore(&intr->lock, flags);
 395         return urb != NULL;
 396 }
 397
 398 int zd_usb_enable_int(struct zd_usb *usb)
 399 {
 400         int r;
 401         struct usb_device *udev;
 402         struct zd_usb_interrupt *intr = &usb->intr;
 403         void *transfer_buffer = NULL;
 404         struct urb *urb;
 405
 406         dev_dbg_f(zd_usb_dev(usb), "\n");
 407
 408         urb = usb_alloc_urb(0, GFP_NOFS);
 409         if (!urb) {
 410                 r = -ENOMEM;
 411                 goto out;
 412         }
 413
 414         ZD_ASSERT(!irqs_disabled());
 415         spin_lock_irq(&intr->lock);
 416         if (intr->urb) {
 417                 spin_unlock_irq(&intr->lock);
 418                 r = 0;
 419                 goto error_free_urb;
 420         }
 421         intr->urb = urb;
 422         spin_unlock_irq(&intr->lock);
 423
 424         /* TODO: make it a DMA buffer */
 425         r = -ENOMEM;
 426         transfer_buffer = kmalloc(USB_MAX_EP_INT_BUFFER, GFP_NOFS);
 427         if (!transfer_buffer) {
 428                 dev_dbg_f(zd_usb_dev(usb),
 429                         "couldn't allocate transfer_buffer\n");
 430                 goto error_set_urb_null;
 431         }
 432
 433         udev = zd_usb_to_usbdev(usb);
 434         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
 435                          transfer_buffer, USB_MAX_EP_INT_BUFFER,
 436                          int_urb_complete, usb,
 437                          intr->interval);
 438
 439         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
 440         r = usb_submit_urb(urb, GFP_NOFS);
 441         if (r) {
 442                 dev_dbg_f(zd_usb_dev(usb),
 443                          "Couldn't submit urb. Error number %d\n", r);
 444                 goto error;
 445         }
 446
 447         return 0;
 448 error:
 449         kfree(transfer_buffer);
 450 error_set_urb_null:
 451         spin_lock_irq(&intr->lock);
 452         intr->urb = NULL;
 453         spin_unlock_irq(&intr->lock);
 454 error_free_urb:
 455         usb_free_urb(urb);
 456 out:
 457         return r;
 458 }
 459
 460 void zd_usb_disable_int(struct zd_usb *usb)
 461 {
 462         unsigned long flags;
 463         struct zd_usb_interrupt *intr = &usb->intr;
 464         struct urb *urb;
 465
 466         spin_lock_irqsave(&intr->lock, flags);
 467         urb = intr->urb;
 468         if (!urb) {
 469                 spin_unlock_irqrestore(&intr->lock, flags);
 470                 return;
 471         }
 472         intr->urb = NULL;
 473         spin_unlock_irqrestore(&intr->lock, flags);
 474
 475         usb_kill_urb(urb);
 476         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
 477         usb_free_urb(urb);
 478 }
 479
 480 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
 481                              unsigned int length)
 482 {
 483         int i;
 484         struct zd_mac *mac = zd_usb_to_mac(usb);
 485         const struct rx_length_info *length_info;
 486
 487         if (length < sizeof(struct rx_length_info)) {
 488                 /* It's not a complete packet anyhow. */
 489                 return;
 490         }
 491         length_info = (struct rx_length_info *)
 492                 (buffer + length - sizeof(struct rx_length_info));
 493
 494         /* It might be that three frames are merged into a single URB
 495          * transaction. We have to check for the length info tag.
 496          *
 497          * While testing we discovered that length_info might be unaligned,
 498          * because if USB transactions are merged, the last packet will not
 499          * be padded. Unaligned access might also happen if the length_info
 500          * structure is not present.
 501          */
 502         if (get_unaligned(&length_info->tag) == cpu_to_le16(RX_LENGTH_INFO_TAG))
 503         {
 504                 unsigned int l, k, n;
 505                 for (i = 0, l = 0;; i++) {
 506                         k = le16_to_cpu(get_unaligned(&length_info->length[i]));
 507                         if (k == 0)
 508                                 return;
 509                         n = l+k;
 510                         if (n > length)
 511                                 return;
 512                         zd_mac_rx_irq(mac, buffer+l, k);
 513                         if (i >= 2)
 514                                 return;
 515                         l = (n+3) & ~3;
 516                 }
 517         } else {
 518                 zd_mac_rx_irq(mac, buffer, length);
 519         }
 520 }
 521
 522 static void rx_urb_complete(struct urb *urb)
 523 {
 524         struct zd_usb *usb;
 525         struct zd_usb_rx *rx;
 526         const u8 *buffer;
 527         unsigned int length;
 528
 529         switch (urb->status) {
 530         case 0:
 531                 break;
 532         case -ESHUTDOWN:
 533         case -EINVAL:
 534         case -ENODEV:
 535         case -ENOENT:
 536         case -ECONNRESET:
 537         case -EPIPE:
 538                 return;
 539         default:
 540                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 541                 goto resubmit;
 542         }
 543
 544         buffer = urb->transfer_buffer;
 545         length = urb->actual_length;
 546         usb = urb->context;
 547         rx = &usb->rx;
 548
 549         if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
 550                 /* If there is an old first fragment, we don't care. */
 551                 dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
 552                 ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
 553                 spin_lock(&rx->lock);
 554                 memcpy(rx->fragment, buffer, length);
 555                 rx->fragment_length = length;
 556                 spin_unlock(&rx->lock);
 557                 goto resubmit;
 558         }
 559
 560         spin_lock(&rx->lock);
 561         if (rx->fragment_length > 0) {
 562                 /* We are on a second fragment, we believe */
 563                 ZD_ASSERT(length + rx->fragment_length <=
 564                           ARRAY_SIZE(rx->fragment));
 565                 dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
 566                 memcpy(rx->fragment+rx->fragment_length, buffer, length);
 567                 handle_rx_packet(usb, rx->fragment,
 568                                  rx->fragment_length + length);
 569                 rx->fragment_length = 0;
 570                 spin_unlock(&rx->lock);
 571         } else {
 572                 spin_unlock(&rx->lock);
 573                 handle_rx_packet(usb, buffer, length);
 574         }
 575
 576 resubmit:
 577         usb_submit_urb(urb, GFP_ATOMIC);
 578 }
 579
 580 static struct urb *alloc_urb(struct zd_usb *usb)
 581 {
 582         struct usb_device *udev = zd_usb_to_usbdev(usb);
 583         struct urb *urb;
 584         void *buffer;
 585
 586         urb = usb_alloc_urb(0, GFP_NOFS);
 587         if (!urb)
 588                 return NULL;
 589         buffer = usb_buffer_alloc(udev, USB_MAX_RX_SIZE, GFP_NOFS,
 590                                   &urb->transfer_dma);
 591         if (!buffer) {
 592                 usb_free_urb(urb);
 593                 return NULL;
 594         }
 595
 596         usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
 597                           buffer, USB_MAX_RX_SIZE,
 598                           rx_urb_complete, usb);
 599         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 600
 601         return urb;
 602 }
 603
 604 static void free_urb(struct urb *urb)
 605 {
 606         if (!urb)
 607                 return;
 608         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 609                         urb->transfer_buffer, urb->transfer_dma);
 610         usb_free_urb(urb);
 611 }
 612
 613 int zd_usb_enable_rx(struct zd_usb *usb)
 614 {
 615         int i, r;
 616         struct zd_usb_rx *rx = &usb->rx;
 617         struct urb **urbs;
 618
 619         dev_dbg_f(zd_usb_dev(usb), "\n");
 620
 621         r = -ENOMEM;
 622         urbs = kcalloc(URBS_COUNT, sizeof(struct urb *), GFP_NOFS);
 623         if (!urbs)
 624                 goto error;
 625         for (i = 0; i < URBS_COUNT; i++) {
 626                 urbs[i] = alloc_urb(usb);
 627                 if (!urbs[i])
 628                         goto error;
 629         }
 630
 631         ZD_ASSERT(!irqs_disabled());
 632         spin_lock_irq(&rx->lock);
 633         if (rx->urbs) {
 634                 spin_unlock_irq(&rx->lock);
 635                 r = 0;
 636                 goto error;
 637         }
 638         rx->urbs = urbs;
 639         rx->urbs_count = URBS_COUNT;
 640         spin_unlock_irq(&rx->lock);
 641
 642         for (i = 0; i < URBS_COUNT; i++) {
 643                 r = usb_submit_urb(urbs[i], GFP_NOFS);
 644                 if (r)
 645                         goto error_submit;
 646         }
 647
 648         return 0;
 649 error_submit:
 650         for (i = 0; i < URBS_COUNT; i++) {
 651                 usb_kill_urb(urbs[i]);
 652         }
 653         spin_lock_irq(&rx->lock);
 654         rx->urbs = NULL;
 655         rx->urbs_count = 0;
 656         spin_unlock_irq(&rx->lock);
 657 error:
 658         if (urbs) {
 659                 for (i = 0; i < URBS_COUNT; i++)
 660                         free_urb(urbs[i]);
 661         }
 662         return r;
 663 }
 664
 665 void zd_usb_disable_rx(struct zd_usb *usb)
 666 {
 667         int i;
 668         unsigned long flags;
 669         struct urb **urbs;
 670         unsigned int count;
 671         struct zd_usb_rx *rx = &usb->rx;
 672
 673         spin_lock_irqsave(&rx->lock, flags);
 674         urbs = rx->urbs;
 675         count = rx->urbs_count;
 676         spin_unlock_irqrestore(&rx->lock, flags);
 677         if (!urbs)
 678                 return;
 679
 680         for (i = 0; i < count; i++) {
 681                 usb_kill_urb(urbs[i]);
 682                 free_urb(urbs[i]);
 683         }
 684         kfree(urbs);
 685
 686         spin_lock_irqsave(&rx->lock, flags);
 687         rx->urbs = NULL;
 688         rx->urbs_count = 0;
 689         spin_unlock_irqrestore(&rx->lock, flags);
 690 }
 691
 692 static void tx_urb_complete(struct urb *urb)
 693 {
 694         int r;
 695
 696         switch (urb->status) {
 697         case 0:
 698                 break;
 699         case -ESHUTDOWN:
 700         case -EINVAL:
 701         case -ENODEV:
 702         case -ENOENT:
 703         case -ECONNRESET:
 704         case -EPIPE:
 705                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 706                 break;
 707         default:
 708                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 709                 goto resubmit;
 710         }
 711 free_urb:
 712         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 713                         urb->transfer_buffer, urb->transfer_dma);
 714         usb_free_urb(urb);
 715         return;
 716 resubmit:
 717         r = usb_submit_urb(urb, GFP_ATOMIC);
 718         if (r) {
 719                 dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
 720                 goto free_urb;
 721         }
 722 }
 723
 724 /* Puts the frame on the USB endpoint. It doesn't wait for
 725  * completion. The frame must contain the control set.
 726  */
 727 int zd_usb_tx(struct zd_usb *usb, const u8 *frame, unsigned int length)
 728 {
 729         int r;
 730         struct usb_device *udev = zd_usb_to_usbdev(usb);
 731         struct urb *urb;
 732         void *buffer;
 733
 734         urb = usb_alloc_urb(0, GFP_ATOMIC);
 735         if (!urb) {
 736                 r = -ENOMEM;
 737                 goto out;
 738         }
 739
 740         buffer = usb_buffer_alloc(zd_usb_to_usbdev(usb), length, GFP_ATOMIC,
 741                                   &urb->transfer_dma);
 742         if (!buffer) {
 743                 r = -ENOMEM;
 744                 goto error_free_urb;
 745         }
 746         memcpy(buffer, frame, length);
 747
 748         usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
 749                           buffer, length, tx_urb_complete, NULL);
 750         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 751
 752         r = usb_submit_urb(urb, GFP_ATOMIC);
 753         if (r)
 754                 goto error;
 755         return 0;
 756 error:
 757         usb_buffer_free(zd_usb_to_usbdev(usb), length, buffer,
 758                         urb->transfer_dma);
 759 error_free_urb:
 760         usb_free_urb(urb);
 761 out:
 762         return r;
 763 }
 764
 765 static inline void init_usb_interrupt(struct zd_usb *usb)
 766 {
 767         struct zd_usb_interrupt *intr = &usb->intr;
 768
 769         spin_lock_init(&intr->lock);
 770         intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
 771         init_completion(&intr->read_regs.completion);
 772         intr->read_regs.cr_int_addr = cpu_to_le16((u16)CR_INTERRUPT);
 773 }
 774
 775 static inline void init_usb_rx(struct zd_usb *usb)
 776 {
 777         struct zd_usb_rx *rx = &usb->rx;
 778         spin_lock_init(&rx->lock);
 779         if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
 780                 rx->usb_packet_size = 512;
 781         } else {
 782                 rx->usb_packet_size = 64;
 783         }
 784         ZD_ASSERT(rx->fragment_length == 0);
 785 }
 786
 787 static inline void init_usb_tx(struct zd_usb *usb)
 788 {
 789         /* FIXME: at this point we will allocate a fixed number of urb's for
 790          * use in a cyclic scheme */
 791 }
 792
 793 void zd_usb_init(struct zd_usb *usb, struct net_device *netdev,
 794                  struct usb_interface *intf)
 795 {
 796         memset(usb, 0, sizeof(*usb));
 797         usb->intf = usb_get_intf(intf);
 798         usb_set_intfdata(usb->intf, netdev);
 799         init_usb_interrupt(usb);
 800         init_usb_tx(usb);
 801         init_usb_rx(usb);
 802 }
 803
 804 void zd_usb_clear(struct zd_usb *usb)
 805 {
 806         usb_set_intfdata(usb->intf, NULL);
 807         usb_put_intf(usb->intf);
 808         ZD_MEMCLEAR(usb, sizeof(*usb));
 809         /* FIXME: usb_interrupt, usb_tx, usb_rx? */
 810 }
 811
 812 static const char *speed(enum usb_device_speed speed)
 813 {
 814         switch (speed) {
 815         case USB_SPEED_LOW:
 816                 return "low";
 817         case USB_SPEED_FULL:
 818                 return "full";
 819         case USB_SPEED_HIGH:
 820                 return "high";
 821         default:
 822                 return "unknown speed";
 823         }
 824 }
 825
 826 static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
 827 {
 828         return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
 829                 le16_to_cpu(udev->descriptor.idVendor),
 830                 le16_to_cpu(udev->descriptor.idProduct),
 831                 get_bcdDevice(udev),
 832                 speed(udev->speed));
 833 }
 834
 835 int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
 836 {
 837         struct usb_device *udev = interface_to_usbdev(usb->intf);
 838         return scnprint_id(udev, buffer, size);
 839 }
 840
 841 #ifdef DEBUG
 842 static void print_id(struct usb_device *udev)
 843 {
 844         char buffer[40];
 845
 846         scnprint_id(udev, buffer, sizeof(buffer));
 847         buffer[sizeof(buffer)-1] = 0;
 848         dev_dbg_f(&udev->dev, "%s\n", buffer);
 849 }
 850 #else
 851 #define print_id(udev) do { } while (0)
 852 #endif
 853
 854 static int eject_installer(struct usb_interface *intf)
 855 {
 856         struct usb_device *udev = interface_to_usbdev(intf);
 857         struct usb_host_interface *iface_desc = &intf->altsetting[0];
 858         struct usb_endpoint_descriptor *endpoint;
 859         unsigned char *cmd;
 860         u8 bulk_out_ep;
 861         int r;
 862
 863         /* Find bulk out endpoint */
 864         endpoint = &iface_desc->endpoint[1].desc;
 865         if ((endpoint->bEndpointAddress & USB_TYPE_MASK) == USB_DIR_OUT &&
 866             (endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
 867             USB_ENDPOINT_XFER_BULK) {
 868                 bulk_out_ep = endpoint->bEndpointAddress;
 869         } else {
 870                 dev_err(&udev->dev,
 871                         "zd1211rw: Could not find bulk out endpoint\n");
 872                 return -ENODEV;
 873         }
 874
 875         cmd = kzalloc(31, GFP_KERNEL);
 876         if (cmd == NULL)
 877                 return -ENODEV;
 878
 879         /* USB bulk command block */
 880         cmd[0] = 0x55;  /* bulk command signature */
 881         cmd[1] = 0x53;  /* bulk command signature */
 882         cmd[2] = 0x42;  /* bulk command signature */
 883         cmd[3] = 0x43;  /* bulk command signature */
 884         cmd[14] = 6;    /* command length */
 885
 886         cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
 887         cmd[19] = 0x2;  /* eject disc */
 888
 889         dev_info(&udev->dev, "Ejecting virtual installer media...\n");
 890         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
 891                 cmd, 31, NULL, 2000);
 892         kfree(cmd);
 893         if (r)
 894                 return r;
 895
 896         /* At this point, the device disconnects and reconnects with the real
 897          * ID numbers. */
 898
 899         usb_set_intfdata(intf, NULL);
 900         return 0;
 901 }
 902
 903 static int probe(struct usb_interface *intf, const struct usb_device_id *id)
 904 {
 905         int r;
 906         struct usb_device *udev = interface_to_usbdev(intf);
 907         struct net_device *netdev = NULL;
 908
 909         print_id(udev);
 910
 911         if (id->driver_info & DEVICE_INSTALLER)
 912                 return eject_installer(intf);
 913
 914         switch (udev->speed) {
 915         case USB_SPEED_LOW:
 916         case USB_SPEED_FULL:
 917         case USB_SPEED_HIGH:
 918                 break;
 919         default:
 920                 dev_dbg_f(&intf->dev, "Unknown USB speed\n");
 921                 r = -ENODEV;
 922                 goto error;
 923         }
 924
 925         netdev = zd_netdev_alloc(intf);
 926         if (netdev == NULL) {
 927                 r = -ENOMEM;
 928                 goto error;
 929         }
 930
 931         r = upload_firmware(udev, id->driver_info);
 932         if (r) {
 933                 dev_err(&intf->dev,
 934                        "couldn't load firmware. Error number %d\n", r);
 935                 goto error;
 936         }
 937
 938         r = usb_reset_configuration(udev);
 939         if (r) {
 940                 dev_dbg_f(&intf->dev,
 941                         "couldn't reset configuration. Error number %d\n", r);
 942                 goto error;
 943         }
 944
 945         /* At this point the interrupt endpoint is not generally enabled. We
 946          * save the USB bandwidth until the network device is opened. But
 947          * notify that the initialization of the MAC will require the
 948          * interrupts to be temporary enabled.
 949          */
 950         r = zd_mac_init_hw(zd_netdev_mac(netdev), id->driver_info);
 951         if (r) {
 952                 dev_dbg_f(&intf->dev,
 953                          "couldn't initialize mac. Error number %d\n", r);
 954                 goto error;
 955         }
 956
 957         r = register_netdev(netdev);
 958         if (r) {
 959                 dev_dbg_f(&intf->dev,
 960                          "couldn't register netdev. Error number %d\n", r);
 961                 goto error;
 962         }
 963
 964         dev_dbg_f(&intf->dev, "successful\n");
 965         dev_info(&intf->dev,"%s\n", netdev->name);
 966         return 0;
 967 error:
 968         usb_reset_device(interface_to_usbdev(intf));
 969         zd_netdev_free(netdev);
 970         return r;
 971 }
 972
 973 static void disconnect(struct usb_interface *intf)
 974 {
 975         struct net_device *netdev = zd_intf_to_netdev(intf);
 976         struct zd_mac *mac = zd_netdev_mac(netdev);
 977         struct zd_usb *usb = &mac->chip.usb;
 978
 979         /* Either something really bad happened, or we're just dealing with
 980          * a DEVICE_INSTALLER. */
 981         if (netdev == NULL)
 982                 return;
 983
 984         dev_dbg_f(zd_usb_dev(usb), "\n");
 985
 986         zd_netdev_disconnect(netdev);
 987
 988         /* Just in case something has gone wrong! */
 989         zd_usb_disable_rx(usb);
 990         zd_usb_disable_int(usb);
 991
 992         /* If the disconnect has been caused by a removal of the
 993          * driver module, the reset allows reloading of the driver. If the
 994          * reset will not be executed here, the upload of the firmware in the
 995          * probe function caused by the reloading of the driver will fail.
 996          */
 997         usb_reset_device(interface_to_usbdev(intf));
 998
 999         zd_netdev_free(netdev);
1000         dev_dbg(&intf->dev, "disconnected\n");
1001 }
1002
1003 static struct usb_driver driver = {
1004         .name           = "zd1211rw",
1005         .id_table       = usb_ids,
1006         .probe          = probe,
1007         .disconnect     = disconnect,
1008 };
1009
1010 struct workqueue_struct *zd_workqueue;
1011
1012 static int __init usb_init(void)
1013 {
1014         int r;
1015
1016         pr_debug("%s usb_init()\n", driver.name);
1017
1018         zd_workqueue = create_singlethread_workqueue(driver.name);
1019         if (zd_workqueue == NULL) {
1020                 printk(KERN_ERR "%s couldn't create workqueue\n", driver.name);
1021                 return -ENOMEM;
1022         }
1023
1024         r = usb_register(&driver);
1025         if (r) {
1026                 printk(KERN_ERR "%s usb_register() failed. Error number %d\n",
1027                        driver.name, r);
1028                 return r;
1029         }
1030
1031         pr_debug("%s initialized\n", driver.name);
1032         return 0;
1033 }
1034
1035 static void __exit usb_exit(void)
1036 {
1037         pr_debug("%s usb_exit()\n", driver.name);
1038         usb_deregister(&driver);
1039         destroy_workqueue(zd_workqueue);
1040 }
1041
1042 module_init(usb_init);
1043 module_exit(usb_exit);
1044
1045 static int usb_int_regs_length(unsigned int count)
1046 {
1047         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1048 }
1049
1050 static void prepare_read_regs_int(struct zd_usb *usb)
1051 {
1052         struct zd_usb_interrupt *intr = &usb->intr;
1053
1054         spin_lock_irq(&intr->lock);
1055         intr->read_regs_enabled = 1;
1056         INIT_COMPLETION(intr->read_regs.completion);
1057         spin_unlock_irq(&intr->lock);
1058 }
1059
1060 static void disable_read_regs_int(struct zd_usb *usb)
1061 {
1062         struct zd_usb_interrupt *intr = &usb->intr;
1063
1064         spin_lock_irq(&intr->lock);
1065         intr->read_regs_enabled = 0;
1066         spin_unlock_irq(&intr->lock);
1067 }
1068
1069 static int get_results(struct zd_usb *usb, u16 *values,
1070                        struct usb_req_read_regs *req, unsigned int count)
1071 {
1072         int r;
1073         int i;
1074         struct zd_usb_interrupt *intr = &usb->intr;
1075         struct read_regs_int *rr = &intr->read_regs;
1076         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1077
1078         spin_lock_irq(&intr->lock);
1079
1080         r = -EIO;
1081         /* The created block size seems to be larger than expected.
1082          * However results appear to be correct.
1083          */
1084         if (rr->length < usb_int_regs_length(count)) {
1085                 dev_dbg_f(zd_usb_dev(usb),
1086                          "error: actual length %d less than expected %d\n",
1087                          rr->length, usb_int_regs_length(count));
1088                 goto error_unlock;
1089         }
1090         if (rr->length > sizeof(rr->buffer)) {
1091                 dev_dbg_f(zd_usb_dev(usb),
1092                          "error: actual length %d exceeds buffer size %zu\n",
1093                          rr->length, sizeof(rr->buffer));
1094                 goto error_unlock;
1095         }
1096
1097         for (i = 0; i < count; i++) {
1098                 struct reg_data *rd = &regs->regs[i];
1099                 if (rd->addr != req->addr[i]) {
1100                         dev_dbg_f(zd_usb_dev(usb),
1101                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1102                                  le16_to_cpu(rd->addr),
1103                                  le16_to_cpu(req->addr[i]));
1104                         goto error_unlock;
1105                 }
1106                 values[i] = le16_to_cpu(rd->value);
1107         }
1108
1109         r = 0;
1110 error_unlock:
1111         spin_unlock_irq(&intr->lock);
1112         return r;
1113 }
1114
1115 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1116                      const zd_addr_t *addresses, unsigned int count)
1117 {
1118         int r;
1119         int i, req_len, actual_req_len;
1120         struct usb_device *udev;
1121         struct usb_req_read_regs *req = NULL;
1122         unsigned long timeout;
1123
1124         if (count < 1) {
1125                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1126                 return -EINVAL;
1127         }
1128         if (count > USB_MAX_IOREAD16_COUNT) {
1129                 dev_dbg_f(zd_usb_dev(usb),
1130                          "error: count %u exceeds possible max %u\n",
1131                          count, USB_MAX_IOREAD16_COUNT);
1132                 return -EINVAL;
1133         }
1134         if (in_atomic()) {
1135                 dev_dbg_f(zd_usb_dev(usb),
1136                          "error: io in atomic context not supported\n");
1137                 return -EWOULDBLOCK;
1138         }
1139         if (!usb_int_enabled(usb)) {
1140                  dev_dbg_f(zd_usb_dev(usb),
1141                           "error: usb interrupt not enabled\n");
1142                 return -EWOULDBLOCK;
1143         }
1144
1145         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1146         req = kmalloc(req_len, GFP_NOFS);
1147         if (!req)
1148                 return -ENOMEM;
1149         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1150         for (i = 0; i < count; i++)
1151                 req->addr[i] = cpu_to_le16((u16)addresses[i]);
1152
1153         udev = zd_usb_to_usbdev(usb);
1154         prepare_read_regs_int(usb);
1155         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1156                          req, req_len, &actual_req_len, 1000 /* ms */);
1157         if (r) {
1158                 dev_dbg_f(zd_usb_dev(usb),
1159                         "error in usb_bulk_msg(). Error number %d\n", r);
1160                 goto error;
1161         }
1162         if (req_len != actual_req_len) {
1163                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()\n"
1164                         " req_len %d != actual_req_len %d\n",
1165                         req_len, actual_req_len);
1166                 r = -EIO;
1167                 goto error;
1168         }
1169
1170         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1171                                               msecs_to_jiffies(1000));
1172         if (!timeout) {
1173                 disable_read_regs_int(usb);
1174                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1175                 r = -ETIMEDOUT;
1176                 goto error;
1177         }
1178
1179         r = get_results(usb, values, req, count);
1180 error:
1181         kfree(req);
1182         return r;
1183 }
1184
1185 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1186                       unsigned int count)
1187 {
1188         int r;
1189         struct usb_device *udev;
1190         struct usb_req_write_regs *req = NULL;
1191         int i, req_len, actual_req_len;
1192
1193         if (count == 0)
1194                 return 0;
1195         if (count > USB_MAX_IOWRITE16_COUNT) {
1196                 dev_dbg_f(zd_usb_dev(usb),
1197                         "error: count %u exceeds possible max %u\n",
1198                         count, USB_MAX_IOWRITE16_COUNT);
1199                 return -EINVAL;
1200         }
1201         if (in_atomic()) {
1202                 dev_dbg_f(zd_usb_dev(usb),
1203                         "error: io in atomic context not supported\n");
1204                 return -EWOULDBLOCK;
1205         }
1206
1207         req_len = sizeof(struct usb_req_write_regs) +
1208                   count * sizeof(struct reg_data);
1209         req = kmalloc(req_len, GFP_NOFS);
1210         if (!req)
1211                 return -ENOMEM;
1212
1213         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1214         for (i = 0; i < count; i++) {
1215                 struct reg_data *rw  = &req->reg_writes[i];
1216                 rw->addr = cpu_to_le16((u16)ioreqs[i].addr);
1217                 rw->value = cpu_to_le16(ioreqs[i].value);
1218         }
1219
1220         udev = zd_usb_to_usbdev(usb);
1221         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1222                          req, req_len, &actual_req_len, 1000 /* ms */);
1223         if (r) {
1224                 dev_dbg_f(zd_usb_dev(usb),
1225                         "error in usb_bulk_msg(). Error number %d\n", r);
1226                 goto error;
1227         }
1228         if (req_len != actual_req_len) {
1229                 dev_dbg_f(zd_usb_dev(usb),
1230                         "error in usb_bulk_msg()"
1231                         " req_len %d != actual_req_len %d\n",
1232                         req_len, actual_req_len);
1233                 r = -EIO;
1234                 goto error;
1235         }
1236
1237         /* FALL-THROUGH with r == 0 */
1238 error:
1239         kfree(req);
1240         return r;
1241 }
1242
1243 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1244 {
1245         int r;
1246         struct usb_device *udev;
1247         struct usb_req_rfwrite *req = NULL;
1248         int i, req_len, actual_req_len;
1249         u16 bit_value_template;
1250
1251         if (in_atomic()) {
1252                 dev_dbg_f(zd_usb_dev(usb),
1253                         "error: io in atomic context not supported\n");
1254                 return -EWOULDBLOCK;
1255         }
1256         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1257                 dev_dbg_f(zd_usb_dev(usb),
1258                         "error: bits %d are smaller than"
1259                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1260                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1261                 return -EINVAL;
1262         }
1263         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1264                 dev_dbg_f(zd_usb_dev(usb),
1265                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1266                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1267                 return -EINVAL;
1268         }
1269 #ifdef DEBUG
1270         if (value & (~0UL << bits)) {
1271                 dev_dbg_f(zd_usb_dev(usb),
1272                         "error: value %#09x has bits >= %d set\n",
1273                         value, bits);
1274                 return -EINVAL;
1275         }
1276 #endif /* DEBUG */
1277
1278         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1279
1280         r = zd_usb_ioread16(usb, &bit_value_template, CR203);
1281         if (r) {
1282                 dev_dbg_f(zd_usb_dev(usb),
1283                         "error %d: Couldn't read CR203\n", r);
1284                 goto out;
1285         }
1286         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1287
1288         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1289         req = kmalloc(req_len, GFP_NOFS);
1290         if (!req)
1291                 return -ENOMEM;
1292
1293         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1294         /* 1: 3683a, but not used in ZYDAS driver */
1295         req->value = cpu_to_le16(2);
1296         req->bits = cpu_to_le16(bits);
1297
1298         for (i = 0; i < bits; i++) {
1299                 u16 bv = bit_value_template;
1300                 if (value & (1 << (bits-1-i)))
1301                         bv |= RF_DATA;
1302                 req->bit_values[i] = cpu_to_le16(bv);
1303         }
1304
1305         udev = zd_usb_to_usbdev(usb);
1306         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1307                          req, req_len, &actual_req_len, 1000 /* ms */);
1308         if (r) {
1309                 dev_dbg_f(zd_usb_dev(usb),
1310                         "error in usb_bulk_msg(). Error number %d\n", r);
1311                 goto out;
1312         }
1313         if (req_len != actual_req_len) {
1314                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()"
1315                         " req_len %d != actual_req_len %d\n",
1316                         req_len, actual_req_len);
1317                 r = -EIO;
1318                 goto out;
1319         }
1320
1321         /* FALL-THROUGH with r == 0 */
1322 out:
1323         kfree(req);
1324         return r;
1325 }