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