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 <net/ieee80211.h>
  28
  29 #include "zd_def.h"
  30 #include "zd_netdev.h"
  31 #include "zd_mac.h"
  32 #include "zd_usb.h"
  33 #include "zd_util.h"
  34
  35 static struct usb_device_id usb_ids[] = {
  36         /* ZD1211 */
  37         { USB_DEVICE(0x0ace, 0x1211), .driver_info = DEVICE_ZD1211 },
  38         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211 },
  39         { USB_DEVICE(0x126f, 0xa006), .driver_info = DEVICE_ZD1211 },
  40         { USB_DEVICE(0x6891, 0xa727), .driver_info = DEVICE_ZD1211 },
  41         { USB_DEVICE(0x0df6, 0x9071), .driver_info = DEVICE_ZD1211 },
  42         { USB_DEVICE(0x157e, 0x300b), .driver_info = DEVICE_ZD1211 },
  43         { USB_DEVICE(0x079b, 0x004a), .driver_info = DEVICE_ZD1211 },
  44         { USB_DEVICE(0x1740, 0x2000), .driver_info = DEVICE_ZD1211 },
  45         { USB_DEVICE(0x157e, 0x3204), .driver_info = DEVICE_ZD1211 },
  46         { USB_DEVICE(0x0586, 0x3402), .driver_info = DEVICE_ZD1211 },
  47         { USB_DEVICE(0x0b3b, 0x5630), .driver_info = DEVICE_ZD1211 },
  48         { USB_DEVICE(0x0b05, 0x170c), .driver_info = DEVICE_ZD1211 },
  49         /* ZD1211B */
  50         { USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
  51         { USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
  52         { USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
  53         { USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
  54         /* "Driverless" devices that need ejecting */
  55         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
  56         {}
  57 };
  58
  59 MODULE_LICENSE("GPL");
  60 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
  61 MODULE_AUTHOR("Ulrich Kunitz");
  62 MODULE_AUTHOR("Daniel Drake");
  63 MODULE_VERSION("1.0");
  64 MODULE_DEVICE_TABLE(usb, usb_ids);
  65
  66 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
  67 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
  68
  69 /* register address handling */
  70
  71 #ifdef DEBUG
  72 static int check_addr(struct zd_usb *usb, zd_addr_t addr)
  73 {
  74         u32 base = ZD_ADDR_BASE(addr);
  75         u32 offset = ZD_OFFSET(addr);
  76
  77         if ((u32)addr & ADDR_ZERO_MASK)
  78                 goto invalid_address;
  79         switch (base) {
  80         case USB_BASE:
  81                 break;
  82         case CR_BASE:
  83                 if (offset > CR_MAX_OFFSET) {
  84                         dev_dbg(zd_usb_dev(usb),
  85                                 "CR offset %#010x larger than"
  86                                 " CR_MAX_OFFSET %#10x\n",
  87                                 offset, CR_MAX_OFFSET);
  88                         goto invalid_address;
  89                 }
  90                 if (offset & 1) {
  91                         dev_dbg(zd_usb_dev(usb),
  92                                 "CR offset %#010x is not a multiple of 2\n",
  93                                 offset);
  94                         goto invalid_address;
  95                 }
  96                 break;
  97         case E2P_BASE:
  98                 if (offset > E2P_MAX_OFFSET) {
  99                         dev_dbg(zd_usb_dev(usb),
 100                                 "E2P offset %#010x larger than"
 101                                 " E2P_MAX_OFFSET %#010x\n",
 102                                 offset, E2P_MAX_OFFSET);
 103                         goto invalid_address;
 104                 }
 105                 break;
 106         case FW_BASE:
 107                 if (!usb->fw_base_offset) {
 108                         dev_dbg(zd_usb_dev(usb),
 109                                "ERROR: fw base offset has not been set\n");
 110                         return -EAGAIN;
 111                 }
 112                 if (offset > FW_MAX_OFFSET) {
 113                         dev_dbg(zd_usb_dev(usb),
 114                                 "FW offset %#10x is larger than"
 115                                 " FW_MAX_OFFSET %#010x\n",
 116                                 offset, FW_MAX_OFFSET);
 117                         goto invalid_address;
 118                 }
 119                 break;
 120         default:
 121                 dev_dbg(zd_usb_dev(usb),
 122                         "address has unsupported base %#010x\n", addr);
 123                 goto invalid_address;
 124         }
 125
 126         return 0;
 127 invalid_address:
 128         dev_dbg(zd_usb_dev(usb),
 129                 "ERROR: invalid address: %#010x\n", addr);
 130         return -EINVAL;
 131 }
 132 #endif /* DEBUG */
 133
 134 static u16 usb_addr(struct zd_usb *usb, zd_addr_t addr)
 135 {
 136         u32 base;
 137         u16 offset;
 138
 139         base = ZD_ADDR_BASE(addr);
 140         offset = ZD_OFFSET(addr);
 141
 142         ZD_ASSERT(check_addr(usb, addr) == 0);
 143
 144         switch (base) {
 145         case CR_BASE:
 146                 offset += CR_BASE_OFFSET;
 147                 break;
 148         case E2P_BASE:
 149                 offset += E2P_BASE_OFFSET;
 150                 break;
 151         case FW_BASE:
 152                 offset += usb->fw_base_offset;
 153                 break;
 154         }
 155
 156         return offset;
 157 }
 158
 159 /* USB device initialization */
 160
 161 static int request_fw_file(
 162         const struct firmware **fw, const char *name, struct device *device)
 163 {
 164         int r;
 165
 166         dev_dbg_f(device, "fw name %s\n", name);
 167
 168         r = request_firmware(fw, name, device);
 169         if (r)
 170                 dev_err(device,
 171                        "Could not load firmware file %s. Error number %d\n",
 172                        name, r);
 173         return r;
 174 }
 175
 176 static inline u16 get_bcdDevice(const struct usb_device *udev)
 177 {
 178         return le16_to_cpu(udev->descriptor.bcdDevice);
 179 }
 180
 181 enum upload_code_flags {
 182         REBOOT = 1,
 183 };
 184
 185 /* Ensures that MAX_TRANSFER_SIZE is even. */
 186 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
 187
 188 static int upload_code(struct usb_device *udev,
 189         const u8 *data, size_t size, u16 code_offset, int flags)
 190 {
 191         u8 *p;
 192         int r;
 193
 194         /* USB request blocks need "kmalloced" buffers.
 195          */
 196         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
 197         if (!p) {
 198                 dev_err(&udev->dev, "out of memory\n");
 199                 r = -ENOMEM;
 200                 goto error;
 201         }
 202
 203         size &= ~1;
 204         while (size > 0) {
 205                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
 206                         size : MAX_TRANSFER_SIZE;
 207
 208                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
 209
 210                 memcpy(p, data, transfer_size);
 211                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 212                         USB_REQ_FIRMWARE_DOWNLOAD,
 213                         USB_DIR_OUT | USB_TYPE_VENDOR,
 214                         code_offset, 0, p, transfer_size, 1000 /* ms */);
 215                 if (r < 0) {
 216                         dev_err(&udev->dev,
 217                                "USB control request for firmware upload"
 218                                " failed. Error number %d\n", r);
 219                         goto error;
 220                 }
 221                 transfer_size = r & ~1;
 222
 223                 size -= transfer_size;
 224                 data += transfer_size;
 225                 code_offset += transfer_size/sizeof(u16);
 226         }
 227
 228         if (flags & REBOOT) {
 229                 u8 ret;
 230
 231                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 232                         USB_REQ_FIRMWARE_CONFIRM,
 233                         USB_DIR_IN | USB_TYPE_VENDOR,
 234                         0, 0, &ret, sizeof(ret), 5000 /* ms */);
 235                 if (r != sizeof(ret)) {
 236                         dev_err(&udev->dev,
 237                                 "control request firmeware confirmation failed."
 238                                 " Return value %d\n", r);
 239                         if (r >= 0)
 240                                 r = -ENODEV;
 241                         goto error;
 242                 }
 243                 if (ret & 0x80) {
 244                         dev_err(&udev->dev,
 245                                 "Internal error while downloading."
 246                                 " Firmware confirm return value %#04x\n",
 247                                 (unsigned int)ret);
 248                         r = -ENODEV;
 249                         goto error;
 250                 }
 251                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
 252                         (unsigned int)ret);
 253         }
 254
 255         r = 0;
 256 error:
 257         kfree(p);
 258         return r;
 259 }
 260
 261 static u16 get_word(const void *data, u16 offset)
 262 {
 263         const __le16 *p = data;
 264         return le16_to_cpu(p[offset]);
 265 }
 266
 267 static char *get_fw_name(char *buffer, size_t size, u8 device_type,
 268                        const char* postfix)
 269 {
 270         scnprintf(buffer, size, "%s%s",
 271                 device_type == DEVICE_ZD1211B ?
 272                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
 273                 postfix);
 274         return buffer;
 275 }
 276
 277 static int handle_version_mismatch(struct usb_device *udev, u8 device_type,
 278         const struct firmware *ub_fw)
 279 {
 280         const struct firmware *ur_fw = NULL;
 281         int offset;
 282         int r = 0;
 283         char fw_name[128];
 284
 285         r = request_fw_file(&ur_fw,
 286                 get_fw_name(fw_name, sizeof(fw_name), device_type, "ur"),
 287                 &udev->dev);
 288         if (r)
 289                 goto error;
 290
 291         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START_OFFSET,
 292                 REBOOT);
 293         if (r)
 294                 goto error;
 295
 296         offset = ((EEPROM_REGS_OFFSET + EEPROM_REGS_SIZE) * sizeof(u16));
 297         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
 298                 E2P_BASE_OFFSET + EEPROM_REGS_SIZE, REBOOT);
 299
 300         /* At this point, the vendor driver downloads the whole firmware
 301          * image, hacks around with version IDs, and uploads it again,
 302          * completely overwriting the boot code. We do not do this here as
 303          * it is not required on any tested devices, and it is suspected to
 304          * cause problems. */
 305 error:
 306         release_firmware(ur_fw);
 307         return r;
 308 }
 309
 310 static int upload_firmware(struct usb_device *udev, u8 device_type)
 311 {
 312         int r;
 313         u16 fw_bcdDevice;
 314         u16 bcdDevice;
 315         const struct firmware *ub_fw = NULL;
 316         const struct firmware *uph_fw = NULL;
 317         char fw_name[128];
 318
 319         bcdDevice = get_bcdDevice(udev);
 320
 321         r = request_fw_file(&ub_fw,
 322                 get_fw_name(fw_name, sizeof(fw_name), device_type,  "ub"),
 323                 &udev->dev);
 324         if (r)
 325                 goto error;
 326
 327         fw_bcdDevice = get_word(ub_fw->data, EEPROM_REGS_OFFSET);
 328
 329         if (fw_bcdDevice != bcdDevice) {
 330                 dev_info(&udev->dev,
 331                         "firmware version %#06x and device bootcode version "
 332                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
 333                 if (bcdDevice <= 0x4313)
 334                         dev_warn(&udev->dev, "device has old bootcode, please "
 335                                 "report success or failure\n");
 336
 337                 r = handle_version_mismatch(udev, device_type, ub_fw);
 338                 if (r)
 339                         goto error;
 340         } else {
 341                 dev_dbg_f(&udev->dev,
 342                         "firmware device id %#06x is equal to the "
 343                         "actual device id\n", fw_bcdDevice);
 344         }
 345
 346
 347         r = request_fw_file(&uph_fw,
 348                 get_fw_name(fw_name, sizeof(fw_name), device_type, "uphr"),
 349                 &udev->dev);
 350         if (r)
 351                 goto error;
 352
 353         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START_OFFSET,
 354                         REBOOT);
 355         if (r) {
 356                 dev_err(&udev->dev,
 357                         "Could not upload firmware code uph. Error number %d\n",
 358                         r);
 359         }
 360
 361         /* FALL-THROUGH */
 362 error:
 363         release_firmware(ub_fw);
 364         release_firmware(uph_fw);
 365         return r;
 366 }
 367
 368 static void disable_read_regs_int(struct zd_usb *usb)
 369 {
 370         struct zd_usb_interrupt *intr = &usb->intr;
 371
 372         spin_lock(&intr->lock);
 373         intr->read_regs_enabled = 0;
 374         spin_unlock(&intr->lock);
 375 }
 376
 377 #define urb_dev(urb) (&(urb)->dev->dev)
 378
 379 static inline void handle_regs_int(struct urb *urb)
 380 {
 381         struct zd_usb *usb = urb->context;
 382         struct zd_usb_interrupt *intr = &usb->intr;
 383         int len;
 384
 385         ZD_ASSERT(in_interrupt());
 386         spin_lock(&intr->lock);
 387
 388         if (intr->read_regs_enabled) {
 389                 intr->read_regs.length = len = urb->actual_length;
 390
 391                 if (len > sizeof(intr->read_regs.buffer))
 392                         len = sizeof(intr->read_regs.buffer);
 393                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
 394                 intr->read_regs_enabled = 0;
 395                 complete(&intr->read_regs.completion);
 396                 goto out;
 397         }
 398
 399         dev_dbg_f(urb_dev(urb), "regs interrupt ignored\n");
 400 out:
 401         spin_unlock(&intr->lock);
 402 }
 403
 404 static inline void handle_retry_failed_int(struct urb *urb)
 405 {
 406         dev_dbg_f(urb_dev(urb), "retry failed interrupt\n");
 407 }
 408
 409
 410 static void int_urb_complete(struct urb *urb, struct pt_regs *pt_regs)
 411 {
 412         int r;
 413         struct usb_int_header *hdr;
 414
 415         switch (urb->status) {
 416         case 0:
 417                 break;
 418         case -ESHUTDOWN:
 419         case -EINVAL:
 420         case -ENODEV:
 421         case -ENOENT:
 422         case -ECONNRESET:
 423         case -EPIPE:
 424                 goto kfree;
 425         default:
 426                 goto resubmit;
 427         }
 428
 429         if (urb->actual_length < sizeof(hdr)) {
 430                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
 431                 goto resubmit;
 432         }
 433
 434         hdr = urb->transfer_buffer;
 435         if (hdr->type != USB_INT_TYPE) {
 436                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
 437                 goto resubmit;
 438         }
 439
 440         switch (hdr->id) {
 441         case USB_INT_ID_REGS:
 442                 handle_regs_int(urb);
 443                 break;
 444         case USB_INT_ID_RETRY_FAILED:
 445                 handle_retry_failed_int(urb);
 446                 break;
 447         default:
 448                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
 449                         (unsigned int)hdr->id);
 450                 goto resubmit;
 451         }
 452
 453 resubmit:
 454         r = usb_submit_urb(urb, GFP_ATOMIC);
 455         if (r) {
 456                 dev_dbg_f(urb_dev(urb), "resubmit urb %p\n", urb);
 457                 goto kfree;
 458         }
 459         return;
 460 kfree:
 461         kfree(urb->transfer_buffer);
 462 }
 463
 464 static inline int int_urb_interval(struct usb_device *udev)
 465 {
 466         switch (udev->speed) {
 467         case USB_SPEED_HIGH:
 468                 return 4;
 469         case USB_SPEED_LOW:
 470                 return 10;
 471         case USB_SPEED_FULL:
 472         default:
 473                 return 1;
 474         }
 475 }
 476
 477 static inline int usb_int_enabled(struct zd_usb *usb)
 478 {
 479         unsigned long flags;
 480         struct zd_usb_interrupt *intr = &usb->intr;
 481         struct urb *urb;
 482
 483         spin_lock_irqsave(&intr->lock, flags);
 484         urb = intr->urb;
 485         spin_unlock_irqrestore(&intr->lock, flags);
 486         return urb != NULL;
 487 }
 488
 489 int zd_usb_enable_int(struct zd_usb *usb)
 490 {
 491         int r;
 492         struct usb_device *udev;
 493         struct zd_usb_interrupt *intr = &usb->intr;
 494         void *transfer_buffer = NULL;
 495         struct urb *urb;
 496
 497         dev_dbg_f(zd_usb_dev(usb), "\n");
 498
 499         urb = usb_alloc_urb(0, GFP_NOFS);
 500         if (!urb) {
 501                 r = -ENOMEM;
 502                 goto out;
 503         }
 504
 505         ZD_ASSERT(!irqs_disabled());
 506         spin_lock_irq(&intr->lock);
 507         if (intr->urb) {
 508                 spin_unlock_irq(&intr->lock);
 509                 r = 0;
 510                 goto error_free_urb;
 511         }
 512         intr->urb = urb;
 513         spin_unlock_irq(&intr->lock);
 514
 515         /* TODO: make it a DMA buffer */
 516         r = -ENOMEM;
 517         transfer_buffer = kmalloc(USB_MAX_EP_INT_BUFFER, GFP_NOFS);
 518         if (!transfer_buffer) {
 519                 dev_dbg_f(zd_usb_dev(usb),
 520                         "couldn't allocate transfer_buffer\n");
 521                 goto error_set_urb_null;
 522         }
 523
 524         udev = zd_usb_to_usbdev(usb);
 525         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
 526                          transfer_buffer, USB_MAX_EP_INT_BUFFER,
 527                          int_urb_complete, usb,
 528                          intr->interval);
 529
 530         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
 531         r = usb_submit_urb(urb, GFP_NOFS);
 532         if (r) {
 533                 dev_dbg_f(zd_usb_dev(usb),
 534                          "Couldn't submit urb. Error number %d\n", r);
 535                 goto error;
 536         }
 537
 538         return 0;
 539 error:
 540         kfree(transfer_buffer);
 541 error_set_urb_null:
 542         spin_lock_irq(&intr->lock);
 543         intr->urb = NULL;
 544         spin_unlock_irq(&intr->lock);
 545 error_free_urb:
 546         usb_free_urb(urb);
 547 out:
 548         return r;
 549 }
 550
 551 void zd_usb_disable_int(struct zd_usb *usb)
 552 {
 553         unsigned long flags;
 554         struct zd_usb_interrupt *intr = &usb->intr;
 555         struct urb *urb;
 556
 557         spin_lock_irqsave(&intr->lock, flags);
 558         urb = intr->urb;
 559         if (!urb) {
 560                 spin_unlock_irqrestore(&intr->lock, flags);
 561                 return;
 562         }
 563         intr->urb = NULL;
 564         spin_unlock_irqrestore(&intr->lock, flags);
 565
 566         usb_kill_urb(urb);
 567         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
 568         usb_free_urb(urb);
 569 }
 570
 571 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
 572                              unsigned int length)
 573 {
 574         int i;
 575         struct zd_mac *mac = zd_usb_to_mac(usb);
 576         const struct rx_length_info *length_info;
 577
 578         if (length < sizeof(struct rx_length_info)) {
 579                 /* It's not a complete packet anyhow. */
 580                 return;
 581         }
 582         length_info = (struct rx_length_info *)
 583                 (buffer + length - sizeof(struct rx_length_info));
 584
 585         /* It might be that three frames are merged into a single URB
 586          * transaction. We have to check for the length info tag.
 587          *
 588          * While testing we discovered that length_info might be unaligned,
 589          * because if USB transactions are merged, the last packet will not
 590          * be padded. Unaligned access might also happen if the length_info
 591          * structure is not present.
 592          */
 593         if (get_unaligned(&length_info->tag) == cpu_to_le16(RX_LENGTH_INFO_TAG))
 594         {
 595                 unsigned int l, k, n;
 596                 for (i = 0, l = 0;; i++) {
 597                         k = le16_to_cpu(get_unaligned(&length_info->length[i]));
 598                         n = l+k;
 599                         if (n > length)
 600                                 return;
 601                         zd_mac_rx(mac, buffer+l, k);
 602                         if (i >= 2)
 603                                 return;
 604                         l = (n+3) & ~3;
 605                 }
 606         } else {
 607                 zd_mac_rx(mac, buffer, length);
 608         }
 609 }
 610
 611 static void rx_urb_complete(struct urb *urb, struct pt_regs *pt_regs)
 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, struct pt_regs *pt_regs)
 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 static int __init usb_init(void)
1116 {
1117         int r;
1118
1119         pr_debug("usb_init()\n");
1120
1121         r = usb_register(&driver);
1122         if (r) {
1123                 printk(KERN_ERR "usb_register() failed. Error number %d\n", r);
1124                 return r;
1125         }
1126
1127         pr_debug("zd1211rw initialized\n");
1128         return 0;
1129 }
1130
1131 static void __exit usb_exit(void)
1132 {
1133         pr_debug("usb_exit()\n");
1134         usb_deregister(&driver);
1135 }
1136
1137 module_init(usb_init);
1138 module_exit(usb_exit);
1139
1140 static int usb_int_regs_length(unsigned int count)
1141 {
1142         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1143 }
1144
1145 static void prepare_read_regs_int(struct zd_usb *usb)
1146 {
1147         struct zd_usb_interrupt *intr = &usb->intr;
1148
1149         spin_lock(&intr->lock);
1150         intr->read_regs_enabled = 1;
1151         INIT_COMPLETION(intr->read_regs.completion);
1152         spin_unlock(&intr->lock);
1153 }
1154
1155 static int get_results(struct zd_usb *usb, u16 *values,
1156                        struct usb_req_read_regs *req, unsigned int count)
1157 {
1158         int r;
1159         int i;
1160         struct zd_usb_interrupt *intr = &usb->intr;
1161         struct read_regs_int *rr = &intr->read_regs;
1162         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1163
1164         spin_lock(&intr->lock);
1165
1166         r = -EIO;
1167         /* The created block size seems to be larger than expected.
1168          * However results appear to be correct.
1169          */
1170         if (rr->length < usb_int_regs_length(count)) {
1171                 dev_dbg_f(zd_usb_dev(usb),
1172                          "error: actual length %d less than expected %d\n",
1173                          rr->length, usb_int_regs_length(count));
1174                 goto error_unlock;
1175         }
1176         if (rr->length > sizeof(rr->buffer)) {
1177                 dev_dbg_f(zd_usb_dev(usb),
1178                          "error: actual length %d exceeds buffer size %zu\n",
1179                          rr->length, sizeof(rr->buffer));
1180                 goto error_unlock;
1181         }
1182
1183         for (i = 0; i < count; i++) {
1184                 struct reg_data *rd = &regs->regs[i];
1185                 if (rd->addr != req->addr[i]) {
1186                         dev_dbg_f(zd_usb_dev(usb),
1187                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1188                                  le16_to_cpu(rd->addr),
1189                                  le16_to_cpu(req->addr[i]));
1190                         goto error_unlock;
1191                 }
1192                 values[i] = le16_to_cpu(rd->value);
1193         }
1194
1195         r = 0;
1196 error_unlock:
1197         spin_unlock(&intr->lock);
1198         return r;
1199 }
1200
1201 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1202                      const zd_addr_t *addresses, unsigned int count)
1203 {
1204         int r;
1205         int i, req_len, actual_req_len;
1206         struct usb_device *udev;
1207         struct usb_req_read_regs *req = NULL;
1208         unsigned long timeout;
1209
1210         if (count < 1) {
1211                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1212                 return -EINVAL;
1213         }
1214         if (count > USB_MAX_IOREAD16_COUNT) {
1215                 dev_dbg_f(zd_usb_dev(usb),
1216                          "error: count %u exceeds possible max %u\n",
1217                          count, USB_MAX_IOREAD16_COUNT);
1218                 return -EINVAL;
1219         }
1220         if (in_atomic()) {
1221                 dev_dbg_f(zd_usb_dev(usb),
1222                          "error: io in atomic context not supported\n");
1223                 return -EWOULDBLOCK;
1224         }
1225         if (!usb_int_enabled(usb)) {
1226                  dev_dbg_f(zd_usb_dev(usb),
1227                           "error: usb interrupt not enabled\n");
1228                 return -EWOULDBLOCK;
1229         }
1230
1231         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1232         req = kmalloc(req_len, GFP_NOFS);
1233         if (!req)
1234                 return -ENOMEM;
1235         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1236         for (i = 0; i < count; i++)
1237                 req->addr[i] = cpu_to_le16(usb_addr(usb, addresses[i]));
1238
1239         udev = zd_usb_to_usbdev(usb);
1240         prepare_read_regs_int(usb);
1241         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1242                          req, req_len, &actual_req_len, 1000 /* ms */);
1243         if (r) {
1244                 dev_dbg_f(zd_usb_dev(usb),
1245                         "error in usb_bulk_msg(). Error number %d\n", r);
1246                 goto error;
1247         }
1248         if (req_len != actual_req_len) {
1249                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()\n"
1250                         " req_len %d != actual_req_len %d\n",
1251                         req_len, actual_req_len);
1252                 r = -EIO;
1253                 goto error;
1254         }
1255
1256         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1257                                               msecs_to_jiffies(1000));
1258         if (!timeout) {
1259                 disable_read_regs_int(usb);
1260                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1261                 r = -ETIMEDOUT;
1262                 goto error;
1263         }
1264
1265         r = get_results(usb, values, req, count);
1266 error:
1267         kfree(req);
1268         return r;
1269 }
1270
1271 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1272                       unsigned int count)
1273 {
1274         int r;
1275         struct usb_device *udev;
1276         struct usb_req_write_regs *req = NULL;
1277         int i, req_len, actual_req_len;
1278
1279         if (count == 0)
1280                 return 0;
1281         if (count > USB_MAX_IOWRITE16_COUNT) {
1282                 dev_dbg_f(zd_usb_dev(usb),
1283                         "error: count %u exceeds possible max %u\n",
1284                         count, USB_MAX_IOWRITE16_COUNT);
1285                 return -EINVAL;
1286         }
1287         if (in_atomic()) {
1288                 dev_dbg_f(zd_usb_dev(usb),
1289                         "error: io in atomic context not supported\n");
1290                 return -EWOULDBLOCK;
1291         }
1292
1293         req_len = sizeof(struct usb_req_write_regs) +
1294                   count * sizeof(struct reg_data);
1295         req = kmalloc(req_len, GFP_NOFS);
1296         if (!req)
1297                 return -ENOMEM;
1298
1299         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1300         for (i = 0; i < count; i++) {
1301                 struct reg_data *rw  = &req->reg_writes[i];
1302                 rw->addr = cpu_to_le16(usb_addr(usb, ioreqs[i].addr));
1303                 rw->value = cpu_to_le16(ioreqs[i].value);
1304         }
1305
1306         udev = zd_usb_to_usbdev(usb);
1307         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1308                          req, req_len, &actual_req_len, 1000 /* ms */);
1309         if (r) {
1310                 dev_dbg_f(zd_usb_dev(usb),
1311                         "error in usb_bulk_msg(). Error number %d\n", r);
1312                 goto error;
1313         }
1314         if (req_len != actual_req_len) {
1315                 dev_dbg_f(zd_usb_dev(usb),
1316                         "error in usb_bulk_msg()"
1317                         " req_len %d != actual_req_len %d\n",
1318                         req_len, actual_req_len);
1319                 r = -EIO;
1320                 goto error;
1321         }
1322
1323         /* FALL-THROUGH with r == 0 */
1324 error:
1325         kfree(req);
1326         return r;
1327 }
1328
1329 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1330 {
1331         int r;
1332         struct usb_device *udev;
1333         struct usb_req_rfwrite *req = NULL;
1334         int i, req_len, actual_req_len;
1335         u16 bit_value_template;
1336
1337         if (in_atomic()) {
1338                 dev_dbg_f(zd_usb_dev(usb),
1339                         "error: io in atomic context not supported\n");
1340                 return -EWOULDBLOCK;
1341         }
1342         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1343                 dev_dbg_f(zd_usb_dev(usb),
1344                         "error: bits %d are smaller than"
1345                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1346                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1347                 return -EINVAL;
1348         }
1349         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1350                 dev_dbg_f(zd_usb_dev(usb),
1351                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1352                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1353                 return -EINVAL;
1354         }
1355 #ifdef DEBUG
1356         if (value & (~0UL << bits)) {
1357                 dev_dbg_f(zd_usb_dev(usb),
1358                         "error: value %#09x has bits >= %d set\n",
1359                         value, bits);
1360                 return -EINVAL;
1361         }
1362 #endif /* DEBUG */
1363
1364         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1365
1366         r = zd_usb_ioread16(usb, &bit_value_template, CR203);
1367         if (r) {
1368                 dev_dbg_f(zd_usb_dev(usb),
1369                         "error %d: Couldn't read CR203\n", r);
1370                 goto out;
1371         }
1372         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1373
1374         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1375         req = kmalloc(req_len, GFP_NOFS);
1376         if (!req)
1377                 return -ENOMEM;
1378
1379         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1380         /* 1: 3683a, but not used in ZYDAS driver */
1381         req->value = cpu_to_le16(2);
1382         req->bits = cpu_to_le16(bits);
1383
1384         for (i = 0; i < bits; i++) {
1385                 u16 bv = bit_value_template;
1386                 if (value & (1 << (bits-1-i)))
1387                         bv |= RF_DATA;
1388                 req->bit_values[i] = cpu_to_le16(bv);
1389         }
1390
1391         udev = zd_usb_to_usbdev(usb);
1392         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1393                          req, req_len, &actual_req_len, 1000 /* ms */);
1394         if (r) {
1395                 dev_dbg_f(zd_usb_dev(usb),
1396                         "error in usb_bulk_msg(). Error number %d\n", r);
1397                 goto out;
1398         }
1399         if (req_len != actual_req_len) {
1400                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()"
1401                         " req_len %d != actual_req_len %d\n",
1402                         req_len, actual_req_len);
1403                 r = -EIO;
1404                 goto out;
1405         }
1406
1407         /* FALL-THROUGH with r == 0 */
1408 out:
1409         kfree(req);
1410         return r;
1411 }