git.oblomov.eu Git - linux-2.6/blob - drivers/net/wireless/zd1211rw/zd_usb.c

   1 /* zd_usb.c
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  16  */
  17
  18 #include <asm/unaligned.h>
  19 #include <linux/kernel.h>
  20 #include <linux/init.h>
  21 #include <linux/module.h>
  22 #include <linux/firmware.h>
  23 #include <linux/device.h>
  24 #include <linux/errno.h>
  25 #include <linux/skbuff.h>
  26 #include <linux/usb.h>
  27 #include <linux/workqueue.h>
  28 #include <net/ieee80211.h>
  29
  30 #include "zd_def.h"
  31 #include "zd_netdev.h"
  32 #include "zd_mac.h"
  33 #include "zd_usb.h"
  34 #include "zd_util.h"
  35
  36 static struct usb_device_id usb_ids[] = {
  37         /* ZD1211 */
  38         { USB_DEVICE(0x0ace, 0x1211), .driver_info = DEVICE_ZD1211 },
  39         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211 },
  40         { USB_DEVICE(0x126f, 0xa006), .driver_info = DEVICE_ZD1211 },
  41         { USB_DEVICE(0x6891, 0xa727), .driver_info = DEVICE_ZD1211 },
  42         { USB_DEVICE(0x0df6, 0x9071), .driver_info = DEVICE_ZD1211 },
  43         { USB_DEVICE(0x157e, 0x300b), .driver_info = DEVICE_ZD1211 },
  44         { USB_DEVICE(0x079b, 0x004a), .driver_info = DEVICE_ZD1211 },
  45         { USB_DEVICE(0x1740, 0x2000), .driver_info = DEVICE_ZD1211 },
  46         { USB_DEVICE(0x157e, 0x3204), .driver_info = DEVICE_ZD1211 },
  47         { USB_DEVICE(0x0586, 0x3402), .driver_info = DEVICE_ZD1211 },
  48         { USB_DEVICE(0x0b3b, 0x5630), .driver_info = DEVICE_ZD1211 },
  49         { USB_DEVICE(0x0b05, 0x170c), .driver_info = DEVICE_ZD1211 },
  50         { USB_DEVICE(0x1435, 0x0711), .driver_info = DEVICE_ZD1211 },
  51         { USB_DEVICE(0x0586, 0x3409), .driver_info = DEVICE_ZD1211 },
  52         { USB_DEVICE(0x0b3b, 0x1630), .driver_info = DEVICE_ZD1211 },
  53         { USB_DEVICE(0x0586, 0x3401), .driver_info = DEVICE_ZD1211 },
  54         { USB_DEVICE(0x14ea, 0xab13), .driver_info = DEVICE_ZD1211 },
  55         /* 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         /* "Driverless" devices that need ejecting */
  62         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
  63         {}
  64 };
  65
  66 MODULE_LICENSE("GPL");
  67 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
  68 MODULE_AUTHOR("Ulrich Kunitz");
  69 MODULE_AUTHOR("Daniel Drake");
  70 MODULE_VERSION("1.0");
  71 MODULE_DEVICE_TABLE(usb, usb_ids);
  72
  73 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
  74 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
  75
  76 /* register address handling */
  77
  78 #ifdef DEBUG
  79 static int check_addr(struct zd_usb *usb, zd_addr_t addr)
  80 {
  81         u32 base = ZD_ADDR_BASE(addr);
  82         u32 offset = ZD_OFFSET(addr);
  83
  84         if ((u32)addr & ADDR_ZERO_MASK)
  85                 goto invalid_address;
  86         switch (base) {
  87         case USB_BASE:
  88                 break;
  89         case CR_BASE:
  90                 if (offset > CR_MAX_OFFSET) {
  91                         dev_dbg(zd_usb_dev(usb),
  92                                 "CR offset %#010x larger than"
  93                                 " CR_MAX_OFFSET %#10x\n",
  94                                 offset, CR_MAX_OFFSET);
  95                         goto invalid_address;
  96                 }
  97                 if (offset & 1) {
  98                         dev_dbg(zd_usb_dev(usb),
  99                                 "CR offset %#010x is not a multiple of 2\n",
 100                                 offset);
 101                         goto invalid_address;
 102                 }
 103                 break;
 104         case E2P_BASE:
 105                 if (offset > E2P_MAX_OFFSET) {
 106                         dev_dbg(zd_usb_dev(usb),
 107                                 "E2P offset %#010x larger than"
 108                                 " E2P_MAX_OFFSET %#010x\n",
 109                                 offset, E2P_MAX_OFFSET);
 110                         goto invalid_address;
 111                 }
 112                 break;
 113         case FW_BASE:
 114                 if (!usb->fw_base_offset) {
 115                         dev_dbg(zd_usb_dev(usb),
 116                                "ERROR: fw base offset has not been set\n");
 117                         return -EAGAIN;
 118                 }
 119                 if (offset > FW_MAX_OFFSET) {
 120                         dev_dbg(zd_usb_dev(usb),
 121                                 "FW offset %#10x is larger than"
 122                                 " FW_MAX_OFFSET %#010x\n",
 123                                 offset, FW_MAX_OFFSET);
 124                         goto invalid_address;
 125                 }
 126                 break;
 127         default:
 128                 dev_dbg(zd_usb_dev(usb),
 129                         "address has unsupported base %#010x\n", addr);
 130                 goto invalid_address;
 131         }
 132
 133         return 0;
 134 invalid_address:
 135         dev_dbg(zd_usb_dev(usb),
 136                 "ERROR: invalid address: %#010x\n", addr);
 137         return -EINVAL;
 138 }
 139 #endif /* DEBUG */
 140
 141 static u16 usb_addr(struct zd_usb *usb, zd_addr_t addr)
 142 {
 143         u32 base;
 144         u16 offset;
 145
 146         base = ZD_ADDR_BASE(addr);
 147         offset = ZD_OFFSET(addr);
 148
 149         ZD_ASSERT(check_addr(usb, addr) == 0);
 150
 151         switch (base) {
 152         case CR_BASE:
 153                 offset += CR_BASE_OFFSET;
 154                 break;
 155         case E2P_BASE:
 156                 offset += E2P_BASE_OFFSET;
 157                 break;
 158         case FW_BASE:
 159                 offset += usb->fw_base_offset;
 160                 break;
 161         }
 162
 163         return offset;
 164 }
 165
 166 /* USB device initialization */
 167
 168 static int request_fw_file(
 169         const struct firmware **fw, const char *name, struct device *device)
 170 {
 171         int r;
 172
 173         dev_dbg_f(device, "fw name %s\n", name);
 174
 175         r = request_firmware(fw, name, device);
 176         if (r)
 177                 dev_err(device,
 178                        "Could not load firmware file %s. Error number %d\n",
 179                        name, r);
 180         return r;
 181 }
 182
 183 static inline u16 get_bcdDevice(const struct usb_device *udev)
 184 {
 185         return le16_to_cpu(udev->descriptor.bcdDevice);
 186 }
 187
 188 enum upload_code_flags {
 189         REBOOT = 1,
 190 };
 191
 192 /* Ensures that MAX_TRANSFER_SIZE is even. */
 193 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
 194
 195 static int upload_code(struct usb_device *udev,
 196         const u8 *data, size_t size, u16 code_offset, int flags)
 197 {
 198         u8 *p;
 199         int r;
 200
 201         /* USB request blocks need "kmalloced" buffers.
 202          */
 203         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
 204         if (!p) {
 205                 dev_err(&udev->dev, "out of memory\n");
 206                 r = -ENOMEM;
 207                 goto error;
 208         }
 209
 210         size &= ~1;
 211         while (size > 0) {
 212                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
 213                         size : MAX_TRANSFER_SIZE;
 214
 215                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
 216
 217                 memcpy(p, data, transfer_size);
 218                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 219                         USB_REQ_FIRMWARE_DOWNLOAD,
 220                         USB_DIR_OUT | USB_TYPE_VENDOR,
 221                         code_offset, 0, p, transfer_size, 1000 /* ms */);
 222                 if (r < 0) {
 223                         dev_err(&udev->dev,
 224                                "USB control request for firmware upload"
 225                                " failed. Error number %d\n", r);
 226                         goto error;
 227                 }
 228                 transfer_size = r & ~1;
 229
 230                 size -= transfer_size;
 231                 data += transfer_size;
 232                 code_offset += transfer_size/sizeof(u16);
 233         }
 234
 235         if (flags & REBOOT) {
 236                 u8 ret;
 237
 238                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 239                         USB_REQ_FIRMWARE_CONFIRM,
 240                         USB_DIR_IN | USB_TYPE_VENDOR,
 241                         0, 0, &ret, sizeof(ret), 5000 /* ms */);
 242                 if (r != sizeof(ret)) {
 243                         dev_err(&udev->dev,
 244                                 "control request firmeware confirmation failed."
 245                                 " Return value %d\n", r);
 246                         if (r >= 0)
 247                                 r = -ENODEV;
 248                         goto error;
 249                 }
 250                 if (ret & 0x80) {
 251                         dev_err(&udev->dev,
 252                                 "Internal error while downloading."
 253                                 " Firmware confirm return value %#04x\n",
 254                                 (unsigned int)ret);
 255                         r = -ENODEV;
 256                         goto error;
 257                 }
 258                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
 259                         (unsigned int)ret);
 260         }
 261
 262         r = 0;
 263 error:
 264         kfree(p);
 265         return r;
 266 }
 267
 268 static u16 get_word(const void *data, u16 offset)
 269 {
 270         const __le16 *p = data;
 271         return le16_to_cpu(p[offset]);
 272 }
 273
 274 static char *get_fw_name(char *buffer, size_t size, u8 device_type,
 275                        const char* postfix)
 276 {
 277         scnprintf(buffer, size, "%s%s",
 278                 device_type == DEVICE_ZD1211B ?
 279                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
 280                 postfix);
 281         return buffer;
 282 }
 283
 284 static int handle_version_mismatch(struct usb_device *udev, u8 device_type,
 285         const struct firmware *ub_fw)
 286 {
 287         const struct firmware *ur_fw = NULL;
 288         int offset;
 289         int r = 0;
 290         char fw_name[128];
 291
 292         r = request_fw_file(&ur_fw,
 293                 get_fw_name(fw_name, sizeof(fw_name), device_type, "ur"),
 294                 &udev->dev);
 295         if (r)
 296                 goto error;
 297
 298         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START_OFFSET,
 299                 REBOOT);
 300         if (r)
 301                 goto error;
 302
 303         offset = ((EEPROM_REGS_OFFSET + EEPROM_REGS_SIZE) * sizeof(u16));
 304         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
 305                 E2P_BASE_OFFSET + EEPROM_REGS_SIZE, REBOOT);
 306
 307         /* At this point, the vendor driver downloads the whole firmware
 308          * image, hacks around with version IDs, and uploads it again,
 309          * completely overwriting the boot code. We do not do this here as
 310          * it is not required on any tested devices, and it is suspected to
 311          * cause problems. */
 312 error:
 313         release_firmware(ur_fw);
 314         return r;
 315 }
 316
 317 static int upload_firmware(struct usb_device *udev, u8 device_type)
 318 {
 319         int r;
 320         u16 fw_bcdDevice;
 321         u16 bcdDevice;
 322         const struct firmware *ub_fw = NULL;
 323         const struct firmware *uph_fw = NULL;
 324         char fw_name[128];
 325
 326         bcdDevice = get_bcdDevice(udev);
 327
 328         r = request_fw_file(&ub_fw,
 329                 get_fw_name(fw_name, sizeof(fw_name), device_type,  "ub"),
 330                 &udev->dev);
 331         if (r)
 332                 goto error;
 333
 334         fw_bcdDevice = get_word(ub_fw->data, EEPROM_REGS_OFFSET);
 335
 336         if (fw_bcdDevice != bcdDevice) {
 337                 dev_info(&udev->dev,
 338                         "firmware version %#06x and device bootcode version "
 339                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
 340                 if (bcdDevice <= 0x4313)
 341                         dev_warn(&udev->dev, "device has old bootcode, please "
 342                                 "report success or failure\n");
 343
 344                 r = handle_version_mismatch(udev, device_type, ub_fw);
 345                 if (r)
 346                         goto error;
 347         } else {
 348                 dev_dbg_f(&udev->dev,
 349                         "firmware device id %#06x is equal to the "
 350                         "actual device id\n", fw_bcdDevice);
 351         }
 352
 353
 354         r = request_fw_file(&uph_fw,
 355                 get_fw_name(fw_name, sizeof(fw_name), device_type, "uphr"),
 356                 &udev->dev);
 357         if (r)
 358                 goto error;
 359
 360         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START_OFFSET,
 361                         REBOOT);
 362         if (r) {
 363                 dev_err(&udev->dev,
 364                         "Could not upload firmware code uph. Error number %d\n",
 365                         r);
 366         }
 367
 368         /* FALL-THROUGH */
 369 error:
 370         release_firmware(ub_fw);
 371         release_firmware(uph_fw);
 372         return r;
 373 }
 374
 375 #define urb_dev(urb) (&(urb)->dev->dev)
 376
 377 static inline void handle_regs_int(struct urb *urb)
 378 {
 379         struct zd_usb *usb = urb->context;
 380         struct zd_usb_interrupt *intr = &usb->intr;
 381         int len;
 382
 383         ZD_ASSERT(in_interrupt());
 384         spin_lock(&intr->lock);
 385
 386         if (intr->read_regs_enabled) {
 387                 intr->read_regs.length = len = urb->actual_length;
 388
 389                 if (len > sizeof(intr->read_regs.buffer))
 390                         len = sizeof(intr->read_regs.buffer);
 391                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
 392                 intr->read_regs_enabled = 0;
 393                 complete(&intr->read_regs.completion);
 394                 goto out;
 395         }
 396
 397         dev_dbg_f(urb_dev(urb), "regs interrupt ignored\n");
 398 out:
 399         spin_unlock(&intr->lock);
 400 }
 401
 402 static inline void handle_retry_failed_int(struct urb *urb)
 403 {
 404         dev_dbg_f(urb_dev(urb), "retry failed interrupt\n");
 405 }
 406
 407
 408 static void int_urb_complete(struct urb *urb)
 409 {
 410         int r;
 411         struct usb_int_header *hdr;
 412
 413         switch (urb->status) {
 414         case 0:
 415                 break;
 416         case -ESHUTDOWN:
 417         case -EINVAL:
 418         case -ENODEV:
 419         case -ENOENT:
 420         case -ECONNRESET:
 421         case -EPIPE:
 422                 goto kfree;
 423         default:
 424                 goto resubmit;
 425         }
 426
 427         if (urb->actual_length < sizeof(hdr)) {
 428                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
 429                 goto resubmit;
 430         }
 431
 432         hdr = urb->transfer_buffer;
 433         if (hdr->type != USB_INT_TYPE) {
 434                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
 435                 goto resubmit;
 436         }
 437
 438         switch (hdr->id) {
 439         case USB_INT_ID_REGS:
 440                 handle_regs_int(urb);
 441                 break;
 442         case USB_INT_ID_RETRY_FAILED:
 443                 handle_retry_failed_int(urb);
 444                 break;
 445         default:
 446                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
 447                         (unsigned int)hdr->id);
 448                 goto resubmit;
 449         }
 450
 451 resubmit:
 452         r = usb_submit_urb(urb, GFP_ATOMIC);
 453         if (r) {
 454                 dev_dbg_f(urb_dev(urb), "resubmit urb %p\n", urb);
 455                 goto kfree;
 456         }
 457         return;
 458 kfree:
 459         kfree(urb->transfer_buffer);
 460 }
 461
 462 static inline int int_urb_interval(struct usb_device *udev)
 463 {
 464         switch (udev->speed) {
 465         case USB_SPEED_HIGH:
 466                 return 4;
 467         case USB_SPEED_LOW:
 468                 return 10;
 469         case USB_SPEED_FULL:
 470         default:
 471                 return 1;
 472         }
 473 }
 474
 475 static inline int usb_int_enabled(struct zd_usb *usb)
 476 {
 477         unsigned long flags;
 478         struct zd_usb_interrupt *intr = &usb->intr;
 479         struct urb *urb;
 480
 481         spin_lock_irqsave(&intr->lock, flags);
 482         urb = intr->urb;
 483         spin_unlock_irqrestore(&intr->lock, flags);
 484         return urb != NULL;
 485 }
 486
 487 int zd_usb_enable_int(struct zd_usb *usb)
 488 {
 489         int r;
 490         struct usb_device *udev;
 491         struct zd_usb_interrupt *intr = &usb->intr;
 492         void *transfer_buffer = NULL;
 493         struct urb *urb;
 494
 495         dev_dbg_f(zd_usb_dev(usb), "\n");
 496
 497         urb = usb_alloc_urb(0, GFP_NOFS);
 498         if (!urb) {
 499                 r = -ENOMEM;
 500                 goto out;
 501         }
 502
 503         ZD_ASSERT(!irqs_disabled());
 504         spin_lock_irq(&intr->lock);
 505         if (intr->urb) {
 506                 spin_unlock_irq(&intr->lock);
 507                 r = 0;
 508                 goto error_free_urb;
 509         }
 510         intr->urb = urb;
 511         spin_unlock_irq(&intr->lock);
 512
 513         /* TODO: make it a DMA buffer */
 514         r = -ENOMEM;
 515         transfer_buffer = kmalloc(USB_MAX_EP_INT_BUFFER, GFP_NOFS);
 516         if (!transfer_buffer) {
 517                 dev_dbg_f(zd_usb_dev(usb),
 518                         "couldn't allocate transfer_buffer\n");
 519                 goto error_set_urb_null;
 520         }
 521
 522         udev = zd_usb_to_usbdev(usb);
 523         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
 524                          transfer_buffer, USB_MAX_EP_INT_BUFFER,
 525                          int_urb_complete, usb,
 526                          intr->interval);
 527
 528         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
 529         r = usb_submit_urb(urb, GFP_NOFS);
 530         if (r) {
 531                 dev_dbg_f(zd_usb_dev(usb),
 532                          "Couldn't submit urb. Error number %d\n", r);
 533                 goto error;
 534         }
 535
 536         return 0;
 537 error:
 538         kfree(transfer_buffer);
 539 error_set_urb_null:
 540         spin_lock_irq(&intr->lock);
 541         intr->urb = NULL;
 542         spin_unlock_irq(&intr->lock);
 543 error_free_urb:
 544         usb_free_urb(urb);
 545 out:
 546         return r;
 547 }
 548
 549 void zd_usb_disable_int(struct zd_usb *usb)
 550 {
 551         unsigned long flags;
 552         struct zd_usb_interrupt *intr = &usb->intr;
 553         struct urb *urb;
 554
 555         spin_lock_irqsave(&intr->lock, flags);
 556         urb = intr->urb;
 557         if (!urb) {
 558                 spin_unlock_irqrestore(&intr->lock, flags);
 559                 return;
 560         }
 561         intr->urb = NULL;
 562         spin_unlock_irqrestore(&intr->lock, flags);
 563
 564         usb_kill_urb(urb);
 565         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
 566         usb_free_urb(urb);
 567 }
 568
 569 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
 570                              unsigned int length)
 571 {
 572         int i;
 573         struct zd_mac *mac = zd_usb_to_mac(usb);
 574         const struct rx_length_info *length_info;
 575
 576         if (length < sizeof(struct rx_length_info)) {
 577                 /* It's not a complete packet anyhow. */
 578                 return;
 579         }
 580         length_info = (struct rx_length_info *)
 581                 (buffer + length - sizeof(struct rx_length_info));
 582
 583         /* It might be that three frames are merged into a single URB
 584          * transaction. We have to check for the length info tag.
 585          *
 586          * While testing we discovered that length_info might be unaligned,
 587          * because if USB transactions are merged, the last packet will not
 588          * be padded. Unaligned access might also happen if the length_info
 589          * structure is not present.
 590          */
 591         if (get_unaligned(&length_info->tag) == cpu_to_le16(RX_LENGTH_INFO_TAG))
 592         {
 593                 unsigned int l, k, n;
 594                 for (i = 0, l = 0;; i++) {
 595                         k = le16_to_cpu(get_unaligned(&length_info->length[i]));
 596                         if (k == 0)
 597                                 return;
 598                         n = l+k;
 599                         if (n > length)
 600                                 return;
 601                         zd_mac_rx_irq(mac, buffer+l, k);
 602                         if (i >= 2)
 603                                 return;
 604                         l = (n+3) & ~3;
 605                 }
 606         } else {
 607                 zd_mac_rx_irq(mac, buffer, length);
 608         }
 609 }
 610
 611 static void rx_urb_complete(struct urb *urb)
 612 {
 613         struct zd_usb *usb;
 614         struct zd_usb_rx *rx;
 615         const u8 *buffer;
 616         unsigned int length;
 617
 618         switch (urb->status) {
 619         case 0:
 620                 break;
 621         case -ESHUTDOWN:
 622         case -EINVAL:
 623         case -ENODEV:
 624         case -ENOENT:
 625         case -ECONNRESET:
 626         case -EPIPE:
 627                 return;
 628         default:
 629                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 630                 goto resubmit;
 631         }
 632
 633         buffer = urb->transfer_buffer;
 634         length = urb->actual_length;
 635         usb = urb->context;
 636         rx = &usb->rx;
 637
 638         if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
 639                 /* If there is an old first fragment, we don't care. */
 640                 dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
 641                 ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
 642                 spin_lock(&rx->lock);
 643                 memcpy(rx->fragment, buffer, length);
 644                 rx->fragment_length = length;
 645                 spin_unlock(&rx->lock);
 646                 goto resubmit;
 647         }
 648
 649         spin_lock(&rx->lock);
 650         if (rx->fragment_length > 0) {
 651                 /* We are on a second fragment, we believe */
 652                 ZD_ASSERT(length + rx->fragment_length <=
 653                           ARRAY_SIZE(rx->fragment));
 654                 dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
 655                 memcpy(rx->fragment+rx->fragment_length, buffer, length);
 656                 handle_rx_packet(usb, rx->fragment,
 657                                  rx->fragment_length + length);
 658                 rx->fragment_length = 0;
 659                 spin_unlock(&rx->lock);
 660         } else {
 661                 spin_unlock(&rx->lock);
 662                 handle_rx_packet(usb, buffer, length);
 663         }
 664
 665 resubmit:
 666         usb_submit_urb(urb, GFP_ATOMIC);
 667 }
 668
 669 static struct urb *alloc_urb(struct zd_usb *usb)
 670 {
 671         struct usb_device *udev = zd_usb_to_usbdev(usb);
 672         struct urb *urb;
 673         void *buffer;
 674
 675         urb = usb_alloc_urb(0, GFP_NOFS);
 676         if (!urb)
 677                 return NULL;
 678         buffer = usb_buffer_alloc(udev, USB_MAX_RX_SIZE, GFP_NOFS,
 679                                   &urb->transfer_dma);
 680         if (!buffer) {
 681                 usb_free_urb(urb);
 682                 return NULL;
 683         }
 684
 685         usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
 686                           buffer, USB_MAX_RX_SIZE,
 687                           rx_urb_complete, usb);
 688         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 689
 690         return urb;
 691 }
 692
 693 static void free_urb(struct urb *urb)
 694 {
 695         if (!urb)
 696                 return;
 697         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 698                         urb->transfer_buffer, urb->transfer_dma);
 699         usb_free_urb(urb);
 700 }
 701
 702 int zd_usb_enable_rx(struct zd_usb *usb)
 703 {
 704         int i, r;
 705         struct zd_usb_rx *rx = &usb->rx;
 706         struct urb **urbs;
 707
 708         dev_dbg_f(zd_usb_dev(usb), "\n");
 709
 710         r = -ENOMEM;
 711         urbs = kcalloc(URBS_COUNT, sizeof(struct urb *), GFP_NOFS);
 712         if (!urbs)
 713                 goto error;
 714         for (i = 0; i < URBS_COUNT; i++) {
 715                 urbs[i] = alloc_urb(usb);
 716                 if (!urbs[i])
 717                         goto error;
 718         }
 719
 720         ZD_ASSERT(!irqs_disabled());
 721         spin_lock_irq(&rx->lock);
 722         if (rx->urbs) {
 723                 spin_unlock_irq(&rx->lock);
 724                 r = 0;
 725                 goto error;
 726         }
 727         rx->urbs = urbs;
 728         rx->urbs_count = URBS_COUNT;
 729         spin_unlock_irq(&rx->lock);
 730
 731         for (i = 0; i < URBS_COUNT; i++) {
 732                 r = usb_submit_urb(urbs[i], GFP_NOFS);
 733                 if (r)
 734                         goto error_submit;
 735         }
 736
 737         return 0;
 738 error_submit:
 739         for (i = 0; i < URBS_COUNT; i++) {
 740                 usb_kill_urb(urbs[i]);
 741         }
 742         spin_lock_irq(&rx->lock);
 743         rx->urbs = NULL;
 744         rx->urbs_count = 0;
 745         spin_unlock_irq(&rx->lock);
 746 error:
 747         if (urbs) {
 748                 for (i = 0; i < URBS_COUNT; i++)
 749                         free_urb(urbs[i]);
 750         }
 751         return r;
 752 }
 753
 754 void zd_usb_disable_rx(struct zd_usb *usb)
 755 {
 756         int i;
 757         unsigned long flags;
 758         struct urb **urbs;
 759         unsigned int count;
 760         struct zd_usb_rx *rx = &usb->rx;
 761
 762         spin_lock_irqsave(&rx->lock, flags);
 763         urbs = rx->urbs;
 764         count = rx->urbs_count;
 765         spin_unlock_irqrestore(&rx->lock, flags);
 766         if (!urbs)
 767                 return;
 768
 769         for (i = 0; i < count; i++) {
 770                 usb_kill_urb(urbs[i]);
 771                 free_urb(urbs[i]);
 772         }
 773         kfree(urbs);
 774
 775         spin_lock_irqsave(&rx->lock, flags);
 776         rx->urbs = NULL;
 777         rx->urbs_count = 0;
 778         spin_unlock_irqrestore(&rx->lock, flags);
 779 }
 780
 781 static void tx_urb_complete(struct urb *urb)
 782 {
 783         int r;
 784
 785         switch (urb->status) {
 786         case 0:
 787                 break;
 788         case -ESHUTDOWN:
 789         case -EINVAL:
 790         case -ENODEV:
 791         case -ENOENT:
 792         case -ECONNRESET:
 793         case -EPIPE:
 794                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 795                 break;
 796         default:
 797                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 798                 goto resubmit;
 799         }
 800 free_urb:
 801         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 802                         urb->transfer_buffer, urb->transfer_dma);
 803         usb_free_urb(urb);
 804         return;
 805 resubmit:
 806         r = usb_submit_urb(urb, GFP_ATOMIC);
 807         if (r) {
 808                 dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
 809                 goto free_urb;
 810         }
 811 }
 812
 813 /* Puts the frame on the USB endpoint. It doesn't wait for
 814  * completion. The frame must contain the control set.
 815  */
 816 int zd_usb_tx(struct zd_usb *usb, const u8 *frame, unsigned int length)
 817 {
 818         int r;
 819         struct usb_device *udev = zd_usb_to_usbdev(usb);
 820         struct urb *urb;
 821         void *buffer;
 822
 823         urb = usb_alloc_urb(0, GFP_ATOMIC);
 824         if (!urb) {
 825                 r = -ENOMEM;
 826                 goto out;
 827         }
 828
 829         buffer = usb_buffer_alloc(zd_usb_to_usbdev(usb), length, GFP_ATOMIC,
 830                                   &urb->transfer_dma);
 831         if (!buffer) {
 832                 r = -ENOMEM;
 833                 goto error_free_urb;
 834         }
 835         memcpy(buffer, frame, length);
 836
 837         usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
 838                           buffer, length, tx_urb_complete, NULL);
 839         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 840
 841         r = usb_submit_urb(urb, GFP_ATOMIC);
 842         if (r)
 843                 goto error;
 844         return 0;
 845 error:
 846         usb_buffer_free(zd_usb_to_usbdev(usb), length, buffer,
 847                         urb->transfer_dma);
 848 error_free_urb:
 849         usb_free_urb(urb);
 850 out:
 851         return r;
 852 }
 853
 854 static inline void init_usb_interrupt(struct zd_usb *usb)
 855 {
 856         struct zd_usb_interrupt *intr = &usb->intr;
 857
 858         spin_lock_init(&intr->lock);
 859         intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
 860         init_completion(&intr->read_regs.completion);
 861         intr->read_regs.cr_int_addr = cpu_to_le16(usb_addr(usb, CR_INTERRUPT));
 862 }
 863
 864 static inline void init_usb_rx(struct zd_usb *usb)
 865 {
 866         struct zd_usb_rx *rx = &usb->rx;
 867         spin_lock_init(&rx->lock);
 868         if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
 869                 rx->usb_packet_size = 512;
 870         } else {
 871                 rx->usb_packet_size = 64;
 872         }
 873         ZD_ASSERT(rx->fragment_length == 0);
 874 }
 875
 876 static inline void init_usb_tx(struct zd_usb *usb)
 877 {
 878         /* FIXME: at this point we will allocate a fixed number of urb's for
 879          * use in a cyclic scheme */
 880 }
 881
 882 void zd_usb_init(struct zd_usb *usb, struct net_device *netdev,
 883                  struct usb_interface *intf)
 884 {
 885         memset(usb, 0, sizeof(*usb));
 886         usb->intf = usb_get_intf(intf);
 887         usb_set_intfdata(usb->intf, netdev);
 888         init_usb_interrupt(usb);
 889         init_usb_tx(usb);
 890         init_usb_rx(usb);
 891 }
 892
 893 int zd_usb_init_hw(struct zd_usb *usb)
 894 {
 895         int r;
 896         struct zd_chip *chip = zd_usb_to_chip(usb);
 897
 898         ZD_ASSERT(mutex_is_locked(&chip->mutex));
 899         r = zd_ioread16_locked(chip, &usb->fw_base_offset,
 900                         USB_REG((u16)FW_BASE_ADDR_OFFSET));
 901         if (r)
 902                 return r;
 903         dev_dbg_f(zd_usb_dev(usb), "fw_base_offset: %#06hx\n",
 904                  usb->fw_base_offset);
 905
 906         return 0;
 907 }
 908
 909 void zd_usb_clear(struct zd_usb *usb)
 910 {
 911         usb_set_intfdata(usb->intf, NULL);
 912         usb_put_intf(usb->intf);
 913         ZD_MEMCLEAR(usb, sizeof(*usb));
 914         /* FIXME: usb_interrupt, usb_tx, usb_rx? */
 915 }
 916
 917 static const char *speed(enum usb_device_speed speed)
 918 {
 919         switch (speed) {
 920         case USB_SPEED_LOW:
 921                 return "low";
 922         case USB_SPEED_FULL:
 923                 return "full";
 924         case USB_SPEED_HIGH:
 925                 return "high";
 926         default:
 927                 return "unknown speed";
 928         }
 929 }
 930
 931 static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
 932 {
 933         return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
 934                 le16_to_cpu(udev->descriptor.idVendor),
 935                 le16_to_cpu(udev->descriptor.idProduct),
 936                 get_bcdDevice(udev),
 937                 speed(udev->speed));
 938 }
 939
 940 int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
 941 {
 942         struct usb_device *udev = interface_to_usbdev(usb->intf);
 943         return scnprint_id(udev, buffer, size);
 944 }
 945
 946 #ifdef DEBUG
 947 static void print_id(struct usb_device *udev)
 948 {
 949         char buffer[40];
 950
 951         scnprint_id(udev, buffer, sizeof(buffer));
 952         buffer[sizeof(buffer)-1] = 0;
 953         dev_dbg_f(&udev->dev, "%s\n", buffer);
 954 }
 955 #else
 956 #define print_id(udev) do { } while (0)
 957 #endif
 958
 959 static int eject_installer(struct usb_interface *intf)
 960 {
 961         struct usb_device *udev = interface_to_usbdev(intf);
 962         struct usb_host_interface *iface_desc = &intf->altsetting[0];
 963         struct usb_endpoint_descriptor *endpoint;
 964         unsigned char *cmd;
 965         u8 bulk_out_ep;
 966         int r;
 967
 968         /* Find bulk out endpoint */
 969         endpoint = &iface_desc->endpoint[1].desc;
 970         if ((endpoint->bEndpointAddress & USB_TYPE_MASK) == USB_DIR_OUT &&
 971             (endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
 972             USB_ENDPOINT_XFER_BULK) {
 973                 bulk_out_ep = endpoint->bEndpointAddress;
 974         } else {
 975                 dev_err(&udev->dev,
 976                         "zd1211rw: Could not find bulk out endpoint\n");
 977                 return -ENODEV;
 978         }
 979
 980         cmd = kzalloc(31, GFP_KERNEL);
 981         if (cmd == NULL)
 982                 return -ENODEV;
 983
 984         /* USB bulk command block */
 985         cmd[0] = 0x55;  /* bulk command signature */
 986         cmd[1] = 0x53;  /* bulk command signature */
 987         cmd[2] = 0x42;  /* bulk command signature */
 988         cmd[3] = 0x43;  /* bulk command signature */
 989         cmd[14] = 6;    /* command length */
 990
 991         cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
 992         cmd[19] = 0x2;  /* eject disc */
 993
 994         dev_info(&udev->dev, "Ejecting virtual installer media...\n");
 995         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
 996                 cmd, 31, NULL, 2000);
 997         kfree(cmd);
 998         if (r)
 999                 return r;
1000
1001         /* At this point, the device disconnects and reconnects with the real
1002          * ID numbers. */
1003
1004         usb_set_intfdata(intf, NULL);
1005         return 0;
1006 }
1007
1008 static int probe(struct usb_interface *intf, const struct usb_device_id *id)
1009 {
1010         int r;
1011         struct usb_device *udev = interface_to_usbdev(intf);
1012         struct net_device *netdev = NULL;
1013
1014         print_id(udev);
1015
1016         if (id->driver_info & DEVICE_INSTALLER)
1017                 return eject_installer(intf);
1018
1019         switch (udev->speed) {
1020         case USB_SPEED_LOW:
1021         case USB_SPEED_FULL:
1022         case USB_SPEED_HIGH:
1023                 break;
1024         default:
1025                 dev_dbg_f(&intf->dev, "Unknown USB speed\n");
1026                 r = -ENODEV;
1027                 goto error;
1028         }
1029
1030         netdev = zd_netdev_alloc(intf);
1031         if (netdev == NULL) {
1032                 r = -ENOMEM;
1033                 goto error;
1034         }
1035
1036         r = upload_firmware(udev, id->driver_info);
1037         if (r) {
1038                 dev_err(&intf->dev,
1039                        "couldn't load firmware. Error number %d\n", r);
1040                 goto error;
1041         }
1042
1043         r = usb_reset_configuration(udev);
1044         if (r) {
1045                 dev_dbg_f(&intf->dev,
1046                         "couldn't reset configuration. Error number %d\n", r);
1047                 goto error;
1048         }
1049
1050         /* At this point the interrupt endpoint is not generally enabled. We
1051          * save the USB bandwidth until the network device is opened. But
1052          * notify that the initialization of the MAC will require the
1053          * interrupts to be temporary enabled.
1054          */
1055         r = zd_mac_init_hw(zd_netdev_mac(netdev), id->driver_info);
1056         if (r) {
1057                 dev_dbg_f(&intf->dev,
1058                          "couldn't initialize mac. Error number %d\n", r);
1059                 goto error;
1060         }
1061
1062         r = register_netdev(netdev);
1063         if (r) {
1064                 dev_dbg_f(&intf->dev,
1065                          "couldn't register netdev. Error number %d\n", r);
1066                 goto error;
1067         }
1068
1069         dev_dbg_f(&intf->dev, "successful\n");
1070         dev_info(&intf->dev,"%s\n", netdev->name);
1071         return 0;
1072 error:
1073         usb_reset_device(interface_to_usbdev(intf));
1074         zd_netdev_free(netdev);
1075         return r;
1076 }
1077
1078 static void disconnect(struct usb_interface *intf)
1079 {
1080         struct net_device *netdev = zd_intf_to_netdev(intf);
1081         struct zd_mac *mac = zd_netdev_mac(netdev);
1082         struct zd_usb *usb = &mac->chip.usb;
1083
1084         /* Either something really bad happened, or we're just dealing with
1085          * a DEVICE_INSTALLER. */
1086         if (netdev == NULL)
1087                 return;
1088
1089         dev_dbg_f(zd_usb_dev(usb), "\n");
1090
1091         zd_netdev_disconnect(netdev);
1092
1093         /* Just in case something has gone wrong! */
1094         zd_usb_disable_rx(usb);
1095         zd_usb_disable_int(usb);
1096
1097         /* If the disconnect has been caused by a removal of the
1098          * driver module, the reset allows reloading of the driver. If the
1099          * reset will not be executed here, the upload of the firmware in the
1100          * probe function caused by the reloading of the driver will fail.
1101          */
1102         usb_reset_device(interface_to_usbdev(intf));
1103
1104         zd_netdev_free(netdev);
1105         dev_dbg(&intf->dev, "disconnected\n");
1106 }
1107
1108 static struct usb_driver driver = {
1109         .name           = "zd1211rw",
1110         .id_table       = usb_ids,
1111         .probe          = probe,
1112         .disconnect     = disconnect,
1113 };
1114
1115 struct workqueue_struct *zd_workqueue;
1116
1117 static int __init usb_init(void)
1118 {
1119         int r;
1120
1121         pr_debug("%s usb_init()\n", driver.name);
1122
1123         zd_workqueue = create_singlethread_workqueue(driver.name);
1124         if (zd_workqueue == NULL) {
1125                 printk(KERN_ERR "%s couldn't create workqueue\n", driver.name);
1126                 return -ENOMEM;
1127         }
1128
1129         r = usb_register(&driver);
1130         if (r) {
1131                 printk(KERN_ERR "%s usb_register() failed. Error number %d\n",
1132                        driver.name, r);
1133                 return r;
1134         }
1135
1136         pr_debug("%s initialized\n", driver.name);
1137         return 0;
1138 }
1139
1140 static void __exit usb_exit(void)
1141 {
1142         pr_debug("%s usb_exit()\n", driver.name);
1143         usb_deregister(&driver);
1144         destroy_workqueue(zd_workqueue);
1145 }
1146
1147 module_init(usb_init);
1148 module_exit(usb_exit);
1149
1150 static int usb_int_regs_length(unsigned int count)
1151 {
1152         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1153 }
1154
1155 static void prepare_read_regs_int(struct zd_usb *usb)
1156 {
1157         struct zd_usb_interrupt *intr = &usb->intr;
1158
1159         spin_lock_irq(&intr->lock);
1160         intr->read_regs_enabled = 1;
1161         INIT_COMPLETION(intr->read_regs.completion);
1162         spin_unlock_irq(&intr->lock);
1163 }
1164
1165 static void disable_read_regs_int(struct zd_usb *usb)
1166 {
1167         struct zd_usb_interrupt *intr = &usb->intr;
1168
1169         spin_lock_irq(&intr->lock);
1170         intr->read_regs_enabled = 0;
1171         spin_unlock_irq(&intr->lock);
1172 }
1173
1174 static int get_results(struct zd_usb *usb, u16 *values,
1175                        struct usb_req_read_regs *req, unsigned int count)
1176 {
1177         int r;
1178         int i;
1179         struct zd_usb_interrupt *intr = &usb->intr;
1180         struct read_regs_int *rr = &intr->read_regs;
1181         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1182
1183         spin_lock_irq(&intr->lock);
1184
1185         r = -EIO;
1186         /* The created block size seems to be larger than expected.
1187          * However results appear to be correct.
1188          */
1189         if (rr->length < usb_int_regs_length(count)) {
1190                 dev_dbg_f(zd_usb_dev(usb),
1191                          "error: actual length %d less than expected %d\n",
1192                          rr->length, usb_int_regs_length(count));
1193                 goto error_unlock;
1194         }
1195         if (rr->length > sizeof(rr->buffer)) {
1196                 dev_dbg_f(zd_usb_dev(usb),
1197                          "error: actual length %d exceeds buffer size %zu\n",
1198                          rr->length, sizeof(rr->buffer));
1199                 goto error_unlock;
1200         }
1201
1202         for (i = 0; i < count; i++) {
1203                 struct reg_data *rd = &regs->regs[i];
1204                 if (rd->addr != req->addr[i]) {
1205                         dev_dbg_f(zd_usb_dev(usb),
1206                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1207                                  le16_to_cpu(rd->addr),
1208                                  le16_to_cpu(req->addr[i]));
1209                         goto error_unlock;
1210                 }
1211                 values[i] = le16_to_cpu(rd->value);
1212         }
1213
1214         r = 0;
1215 error_unlock:
1216         spin_unlock_irq(&intr->lock);
1217         return r;
1218 }
1219
1220 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1221                      const zd_addr_t *addresses, unsigned int count)
1222 {
1223         int r;
1224         int i, req_len, actual_req_len;
1225         struct usb_device *udev;
1226         struct usb_req_read_regs *req = NULL;
1227         unsigned long timeout;
1228
1229         if (count < 1) {
1230                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1231                 return -EINVAL;
1232         }
1233         if (count > USB_MAX_IOREAD16_COUNT) {
1234                 dev_dbg_f(zd_usb_dev(usb),
1235                          "error: count %u exceeds possible max %u\n",
1236                          count, USB_MAX_IOREAD16_COUNT);
1237                 return -EINVAL;
1238         }
1239         if (in_atomic()) {
1240                 dev_dbg_f(zd_usb_dev(usb),
1241                          "error: io in atomic context not supported\n");
1242                 return -EWOULDBLOCK;
1243         }
1244         if (!usb_int_enabled(usb)) {
1245                  dev_dbg_f(zd_usb_dev(usb),
1246                           "error: usb interrupt not enabled\n");
1247                 return -EWOULDBLOCK;
1248         }
1249
1250         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1251         req = kmalloc(req_len, GFP_NOFS);
1252         if (!req)
1253                 return -ENOMEM;
1254         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1255         for (i = 0; i < count; i++)
1256                 req->addr[i] = cpu_to_le16(usb_addr(usb, addresses[i]));
1257
1258         udev = zd_usb_to_usbdev(usb);
1259         prepare_read_regs_int(usb);
1260         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1261                          req, req_len, &actual_req_len, 1000 /* ms */);
1262         if (r) {
1263                 dev_dbg_f(zd_usb_dev(usb),
1264                         "error in usb_bulk_msg(). Error number %d\n", r);
1265                 goto error;
1266         }
1267         if (req_len != actual_req_len) {
1268                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()\n"
1269                         " req_len %d != actual_req_len %d\n",
1270                         req_len, actual_req_len);
1271                 r = -EIO;
1272                 goto error;
1273         }
1274
1275         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1276                                               msecs_to_jiffies(1000));
1277         if (!timeout) {
1278                 disable_read_regs_int(usb);
1279                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1280                 r = -ETIMEDOUT;
1281                 goto error;
1282         }
1283
1284         r = get_results(usb, values, req, count);
1285 error:
1286         kfree(req);
1287         return r;
1288 }
1289
1290 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1291                       unsigned int count)
1292 {
1293         int r;
1294         struct usb_device *udev;
1295         struct usb_req_write_regs *req = NULL;
1296         int i, req_len, actual_req_len;
1297
1298         if (count == 0)
1299                 return 0;
1300         if (count > USB_MAX_IOWRITE16_COUNT) {
1301                 dev_dbg_f(zd_usb_dev(usb),
1302                         "error: count %u exceeds possible max %u\n",
1303                         count, USB_MAX_IOWRITE16_COUNT);
1304                 return -EINVAL;
1305         }
1306         if (in_atomic()) {
1307                 dev_dbg_f(zd_usb_dev(usb),
1308                         "error: io in atomic context not supported\n");
1309                 return -EWOULDBLOCK;
1310         }
1311
1312         req_len = sizeof(struct usb_req_write_regs) +
1313                   count * sizeof(struct reg_data);
1314         req = kmalloc(req_len, GFP_NOFS);
1315         if (!req)
1316                 return -ENOMEM;
1317
1318         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1319         for (i = 0; i < count; i++) {
1320                 struct reg_data *rw  = &req->reg_writes[i];
1321                 rw->addr = cpu_to_le16(usb_addr(usb, ioreqs[i].addr));
1322                 rw->value = cpu_to_le16(ioreqs[i].value);
1323         }
1324
1325         udev = zd_usb_to_usbdev(usb);
1326         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1327                          req, req_len, &actual_req_len, 1000 /* ms */);
1328         if (r) {
1329                 dev_dbg_f(zd_usb_dev(usb),
1330                         "error in usb_bulk_msg(). Error number %d\n", r);
1331                 goto error;
1332         }
1333         if (req_len != actual_req_len) {
1334                 dev_dbg_f(zd_usb_dev(usb),
1335                         "error in usb_bulk_msg()"
1336                         " req_len %d != actual_req_len %d\n",
1337                         req_len, actual_req_len);
1338                 r = -EIO;
1339                 goto error;
1340         }
1341
1342         /* FALL-THROUGH with r == 0 */
1343 error:
1344         kfree(req);
1345         return r;
1346 }
1347
1348 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1349 {
1350         int r;
1351         struct usb_device *udev;
1352         struct usb_req_rfwrite *req = NULL;
1353         int i, req_len, actual_req_len;
1354         u16 bit_value_template;
1355
1356         if (in_atomic()) {
1357                 dev_dbg_f(zd_usb_dev(usb),
1358                         "error: io in atomic context not supported\n");
1359                 return -EWOULDBLOCK;
1360         }
1361         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1362                 dev_dbg_f(zd_usb_dev(usb),
1363                         "error: bits %d are smaller than"
1364                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1365                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1366                 return -EINVAL;
1367         }
1368         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1369                 dev_dbg_f(zd_usb_dev(usb),
1370                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1371                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1372                 return -EINVAL;
1373         }
1374 #ifdef DEBUG
1375         if (value & (~0UL << bits)) {
1376                 dev_dbg_f(zd_usb_dev(usb),
1377                         "error: value %#09x has bits >= %d set\n",
1378                         value, bits);
1379                 return -EINVAL;
1380         }
1381 #endif /* DEBUG */
1382
1383         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1384
1385         r = zd_usb_ioread16(usb, &bit_value_template, CR203);
1386         if (r) {
1387                 dev_dbg_f(zd_usb_dev(usb),
1388                         "error %d: Couldn't read CR203\n", r);
1389                 goto out;
1390         }
1391         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1392
1393         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1394         req = kmalloc(req_len, GFP_NOFS);
1395         if (!req)
1396                 return -ENOMEM;
1397
1398         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1399         /* 1: 3683a, but not used in ZYDAS driver */
1400         req->value = cpu_to_le16(2);
1401         req->bits = cpu_to_le16(bits);
1402
1403         for (i = 0; i < bits; i++) {
1404                 u16 bv = bit_value_template;
1405                 if (value & (1 << (bits-1-i)))
1406                         bv |= RF_DATA;
1407                 req->bit_values[i] = cpu_to_le16(bv);
1408         }
1409
1410         udev = zd_usb_to_usbdev(usb);
1411         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1412                          req, req_len, &actual_req_len, 1000 /* ms */);
1413         if (r) {
1414                 dev_dbg_f(zd_usb_dev(usb),
1415                         "error in usb_bulk_msg(). Error number %d\n", r);
1416                 goto out;
1417         }
1418         if (req_len != actual_req_len) {
1419                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()"
1420                         " req_len %d != actual_req_len %d\n",
1421                         req_len, actual_req_len);
1422                 r = -EIO;
1423                 goto out;
1424         }
1425
1426         /* FALL-THROUGH with r == 0 */
1427 out:
1428         kfree(req);
1429         return r;
1430 }