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         /* ZD1211B */
  51         { USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
  52         { USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
  53         { USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
  54         { USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
  55         /* "Driverless" devices that need ejecting */
  56         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
  57         {}
  58 };
  59
  60 MODULE_LICENSE("GPL");
  61 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
  62 MODULE_AUTHOR("Ulrich Kunitz");
  63 MODULE_AUTHOR("Daniel Drake");
  64 MODULE_VERSION("1.0");
  65 MODULE_DEVICE_TABLE(usb, usb_ids);
  66
  67 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
  68 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
  69
  70 /* register address handling */
  71
  72 #ifdef DEBUG
  73 static int check_addr(struct zd_usb *usb, zd_addr_t addr)
  74 {
  75         u32 base = ZD_ADDR_BASE(addr);
  76         u32 offset = ZD_OFFSET(addr);
  77
  78         if ((u32)addr & ADDR_ZERO_MASK)
  79                 goto invalid_address;
  80         switch (base) {
  81         case USB_BASE:
  82                 break;
  83         case CR_BASE:
  84                 if (offset > CR_MAX_OFFSET) {
  85                         dev_dbg(zd_usb_dev(usb),
  86                                 "CR offset %#010x larger than"
  87                                 " CR_MAX_OFFSET %#10x\n",
  88                                 offset, CR_MAX_OFFSET);
  89                         goto invalid_address;
  90                 }
  91                 if (offset & 1) {
  92                         dev_dbg(zd_usb_dev(usb),
  93                                 "CR offset %#010x is not a multiple of 2\n",
  94                                 offset);
  95                         goto invalid_address;
  96                 }
  97                 break;
  98         case E2P_BASE:
  99                 if (offset > E2P_MAX_OFFSET) {
 100                         dev_dbg(zd_usb_dev(usb),
 101                                 "E2P offset %#010x larger than"
 102                                 " E2P_MAX_OFFSET %#010x\n",
 103                                 offset, E2P_MAX_OFFSET);
 104                         goto invalid_address;
 105                 }
 106                 break;
 107         case FW_BASE:
 108                 if (!usb->fw_base_offset) {
 109                         dev_dbg(zd_usb_dev(usb),
 110                                "ERROR: fw base offset has not been set\n");
 111                         return -EAGAIN;
 112                 }
 113                 if (offset > FW_MAX_OFFSET) {
 114                         dev_dbg(zd_usb_dev(usb),
 115                                 "FW offset %#10x is larger than"
 116                                 " FW_MAX_OFFSET %#010x\n",
 117                                 offset, FW_MAX_OFFSET);
 118                         goto invalid_address;
 119                 }
 120                 break;
 121         default:
 122                 dev_dbg(zd_usb_dev(usb),
 123                         "address has unsupported base %#010x\n", addr);
 124                 goto invalid_address;
 125         }
 126
 127         return 0;
 128 invalid_address:
 129         dev_dbg(zd_usb_dev(usb),
 130                 "ERROR: invalid address: %#010x\n", addr);
 131         return -EINVAL;
 132 }
 133 #endif /* DEBUG */
 134
 135 static u16 usb_addr(struct zd_usb *usb, zd_addr_t addr)
 136 {
 137         u32 base;
 138         u16 offset;
 139
 140         base = ZD_ADDR_BASE(addr);
 141         offset = ZD_OFFSET(addr);
 142
 143         ZD_ASSERT(check_addr(usb, addr) == 0);
 144
 145         switch (base) {
 146         case CR_BASE:
 147                 offset += CR_BASE_OFFSET;
 148                 break;
 149         case E2P_BASE:
 150                 offset += E2P_BASE_OFFSET;
 151                 break;
 152         case FW_BASE:
 153                 offset += usb->fw_base_offset;
 154                 break;
 155         }
 156
 157         return offset;
 158 }
 159
 160 /* USB device initialization */
 161
 162 static int request_fw_file(
 163         const struct firmware **fw, const char *name, struct device *device)
 164 {
 165         int r;
 166
 167         dev_dbg_f(device, "fw name %s\n", name);
 168
 169         r = request_firmware(fw, name, device);
 170         if (r)
 171                 dev_err(device,
 172                        "Could not load firmware file %s. Error number %d\n",
 173                        name, r);
 174         return r;
 175 }
 176
 177 static inline u16 get_bcdDevice(const struct usb_device *udev)
 178 {
 179         return le16_to_cpu(udev->descriptor.bcdDevice);
 180 }
 181
 182 enum upload_code_flags {
 183         REBOOT = 1,
 184 };
 185
 186 /* Ensures that MAX_TRANSFER_SIZE is even. */
 187 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
 188
 189 static int upload_code(struct usb_device *udev,
 190         const u8 *data, size_t size, u16 code_offset, int flags)
 191 {
 192         u8 *p;
 193         int r;
 194
 195         /* USB request blocks need "kmalloced" buffers.
 196          */
 197         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
 198         if (!p) {
 199                 dev_err(&udev->dev, "out of memory\n");
 200                 r = -ENOMEM;
 201                 goto error;
 202         }
 203
 204         size &= ~1;
 205         while (size > 0) {
 206                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
 207                         size : MAX_TRANSFER_SIZE;
 208
 209                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
 210
 211                 memcpy(p, data, transfer_size);
 212                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 213                         USB_REQ_FIRMWARE_DOWNLOAD,
 214                         USB_DIR_OUT | USB_TYPE_VENDOR,
 215                         code_offset, 0, p, transfer_size, 1000 /* ms */);
 216                 if (r < 0) {
 217                         dev_err(&udev->dev,
 218                                "USB control request for firmware upload"
 219                                " failed. Error number %d\n", r);
 220                         goto error;
 221                 }
 222                 transfer_size = r & ~1;
 223
 224                 size -= transfer_size;
 225                 data += transfer_size;
 226                 code_offset += transfer_size/sizeof(u16);
 227         }
 228
 229         if (flags & REBOOT) {
 230                 u8 ret;
 231
 232                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 233                         USB_REQ_FIRMWARE_CONFIRM,
 234                         USB_DIR_IN | USB_TYPE_VENDOR,
 235                         0, 0, &ret, sizeof(ret), 5000 /* ms */);
 236                 if (r != sizeof(ret)) {
 237                         dev_err(&udev->dev,
 238                                 "control request firmeware confirmation failed."
 239                                 " Return value %d\n", r);
 240                         if (r >= 0)
 241                                 r = -ENODEV;
 242                         goto error;
 243                 }
 244                 if (ret & 0x80) {
 245                         dev_err(&udev->dev,
 246                                 "Internal error while downloading."
 247                                 " Firmware confirm return value %#04x\n",
 248                                 (unsigned int)ret);
 249                         r = -ENODEV;
 250                         goto error;
 251                 }
 252                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
 253                         (unsigned int)ret);
 254         }
 255
 256         r = 0;
 257 error:
 258         kfree(p);
 259         return r;
 260 }
 261
 262 static u16 get_word(const void *data, u16 offset)
 263 {
 264         const __le16 *p = data;
 265         return le16_to_cpu(p[offset]);
 266 }
 267
 268 static char *get_fw_name(char *buffer, size_t size, u8 device_type,
 269                        const char* postfix)
 270 {
 271         scnprintf(buffer, size, "%s%s",
 272                 device_type == DEVICE_ZD1211B ?
 273                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
 274                 postfix);
 275         return buffer;
 276 }
 277
 278 static int handle_version_mismatch(struct usb_device *udev, u8 device_type,
 279         const struct firmware *ub_fw)
 280 {
 281         const struct firmware *ur_fw = NULL;
 282         int offset;
 283         int r = 0;
 284         char fw_name[128];
 285
 286         r = request_fw_file(&ur_fw,
 287                 get_fw_name(fw_name, sizeof(fw_name), device_type, "ur"),
 288                 &udev->dev);
 289         if (r)
 290                 goto error;
 291
 292         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START_OFFSET,
 293                 REBOOT);
 294         if (r)
 295                 goto error;
 296
 297         offset = ((EEPROM_REGS_OFFSET + EEPROM_REGS_SIZE) * sizeof(u16));
 298         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
 299                 E2P_BASE_OFFSET + EEPROM_REGS_SIZE, REBOOT);
 300
 301         /* At this point, the vendor driver downloads the whole firmware
 302          * image, hacks around with version IDs, and uploads it again,
 303          * completely overwriting the boot code. We do not do this here as
 304          * it is not required on any tested devices, and it is suspected to
 305          * cause problems. */
 306 error:
 307         release_firmware(ur_fw);
 308         return r;
 309 }
 310
 311 static int upload_firmware(struct usb_device *udev, u8 device_type)
 312 {
 313         int r;
 314         u16 fw_bcdDevice;
 315         u16 bcdDevice;
 316         const struct firmware *ub_fw = NULL;
 317         const struct firmware *uph_fw = NULL;
 318         char fw_name[128];
 319
 320         bcdDevice = get_bcdDevice(udev);
 321
 322         r = request_fw_file(&ub_fw,
 323                 get_fw_name(fw_name, sizeof(fw_name), device_type,  "ub"),
 324                 &udev->dev);
 325         if (r)
 326                 goto error;
 327
 328         fw_bcdDevice = get_word(ub_fw->data, EEPROM_REGS_OFFSET);
 329
 330         if (fw_bcdDevice != bcdDevice) {
 331                 dev_info(&udev->dev,
 332                         "firmware version %#06x and device bootcode version "
 333                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
 334                 if (bcdDevice <= 0x4313)
 335                         dev_warn(&udev->dev, "device has old bootcode, please "
 336                                 "report success or failure\n");
 337
 338                 r = handle_version_mismatch(udev, device_type, ub_fw);
 339                 if (r)
 340                         goto error;
 341         } else {
 342                 dev_dbg_f(&udev->dev,
 343                         "firmware device id %#06x is equal to the "
 344                         "actual device id\n", fw_bcdDevice);
 345         }
 346
 347
 348         r = request_fw_file(&uph_fw,
 349                 get_fw_name(fw_name, sizeof(fw_name), device_type, "uphr"),
 350                 &udev->dev);
 351         if (r)
 352                 goto error;
 353
 354         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START_OFFSET,
 355                         REBOOT);
 356         if (r) {
 357                 dev_err(&udev->dev,
 358                         "Could not upload firmware code uph. Error number %d\n",
 359                         r);
 360         }
 361
 362         /* FALL-THROUGH */
 363 error:
 364         release_firmware(ub_fw);
 365         release_firmware(uph_fw);
 366         return r;
 367 }
 368
 369 #define urb_dev(urb) (&(urb)->dev->dev)
 370
 371 static inline void handle_regs_int(struct urb *urb)
 372 {
 373         struct zd_usb *usb = urb->context;
 374         struct zd_usb_interrupt *intr = &usb->intr;
 375         int len;
 376
 377         ZD_ASSERT(in_interrupt());
 378         spin_lock(&intr->lock);
 379
 380         if (intr->read_regs_enabled) {
 381                 intr->read_regs.length = len = urb->actual_length;
 382
 383                 if (len > sizeof(intr->read_regs.buffer))
 384                         len = sizeof(intr->read_regs.buffer);
 385                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
 386                 intr->read_regs_enabled = 0;
 387                 complete(&intr->read_regs.completion);
 388                 goto out;
 389         }
 390
 391         dev_dbg_f(urb_dev(urb), "regs interrupt ignored\n");
 392 out:
 393         spin_unlock(&intr->lock);
 394 }
 395
 396 static inline void handle_retry_failed_int(struct urb *urb)
 397 {
 398         dev_dbg_f(urb_dev(urb), "retry failed interrupt\n");
 399 }
 400
 401
 402 static void int_urb_complete(struct urb *urb)
 403 {
 404         int r;
 405         struct usb_int_header *hdr;
 406
 407         switch (urb->status) {
 408         case 0:
 409                 break;
 410         case -ESHUTDOWN:
 411         case -EINVAL:
 412         case -ENODEV:
 413         case -ENOENT:
 414         case -ECONNRESET:
 415         case -EPIPE:
 416                 goto kfree;
 417         default:
 418                 goto resubmit;
 419         }
 420
 421         if (urb->actual_length < sizeof(hdr)) {
 422                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
 423                 goto resubmit;
 424         }
 425
 426         hdr = urb->transfer_buffer;
 427         if (hdr->type != USB_INT_TYPE) {
 428                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
 429                 goto resubmit;
 430         }
 431
 432         switch (hdr->id) {
 433         case USB_INT_ID_REGS:
 434                 handle_regs_int(urb);
 435                 break;
 436         case USB_INT_ID_RETRY_FAILED:
 437                 handle_retry_failed_int(urb);
 438                 break;
 439         default:
 440                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
 441                         (unsigned int)hdr->id);
 442                 goto resubmit;
 443         }
 444
 445 resubmit:
 446         r = usb_submit_urb(urb, GFP_ATOMIC);
 447         if (r) {
 448                 dev_dbg_f(urb_dev(urb), "resubmit urb %p\n", urb);
 449                 goto kfree;
 450         }
 451         return;
 452 kfree:
 453         kfree(urb->transfer_buffer);
 454 }
 455
 456 static inline int int_urb_interval(struct usb_device *udev)
 457 {
 458         switch (udev->speed) {
 459         case USB_SPEED_HIGH:
 460                 return 4;
 461         case USB_SPEED_LOW:
 462                 return 10;
 463         case USB_SPEED_FULL:
 464         default:
 465                 return 1;
 466         }
 467 }
 468
 469 static inline int usb_int_enabled(struct zd_usb *usb)
 470 {
 471         unsigned long flags;
 472         struct zd_usb_interrupt *intr = &usb->intr;
 473         struct urb *urb;
 474
 475         spin_lock_irqsave(&intr->lock, flags);
 476         urb = intr->urb;
 477         spin_unlock_irqrestore(&intr->lock, flags);
 478         return urb != NULL;
 479 }
 480
 481 int zd_usb_enable_int(struct zd_usb *usb)
 482 {
 483         int r;
 484         struct usb_device *udev;
 485         struct zd_usb_interrupt *intr = &usb->intr;
 486         void *transfer_buffer = NULL;
 487         struct urb *urb;
 488
 489         dev_dbg_f(zd_usb_dev(usb), "\n");
 490
 491         urb = usb_alloc_urb(0, GFP_NOFS);
 492         if (!urb) {
 493                 r = -ENOMEM;
 494                 goto out;
 495         }
 496
 497         ZD_ASSERT(!irqs_disabled());
 498         spin_lock_irq(&intr->lock);
 499         if (intr->urb) {
 500                 spin_unlock_irq(&intr->lock);
 501                 r = 0;
 502                 goto error_free_urb;
 503         }
 504         intr->urb = urb;
 505         spin_unlock_irq(&intr->lock);
 506
 507         /* TODO: make it a DMA buffer */
 508         r = -ENOMEM;
 509         transfer_buffer = kmalloc(USB_MAX_EP_INT_BUFFER, GFP_NOFS);
 510         if (!transfer_buffer) {
 511                 dev_dbg_f(zd_usb_dev(usb),
 512                         "couldn't allocate transfer_buffer\n");
 513                 goto error_set_urb_null;
 514         }
 515
 516         udev = zd_usb_to_usbdev(usb);
 517         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
 518                          transfer_buffer, USB_MAX_EP_INT_BUFFER,
 519                          int_urb_complete, usb,
 520                          intr->interval);
 521
 522         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
 523         r = usb_submit_urb(urb, GFP_NOFS);
 524         if (r) {
 525                 dev_dbg_f(zd_usb_dev(usb),
 526                          "Couldn't submit urb. Error number %d\n", r);
 527                 goto error;
 528         }
 529
 530         return 0;
 531 error:
 532         kfree(transfer_buffer);
 533 error_set_urb_null:
 534         spin_lock_irq(&intr->lock);
 535         intr->urb = NULL;
 536         spin_unlock_irq(&intr->lock);
 537 error_free_urb:
 538         usb_free_urb(urb);
 539 out:
 540         return r;
 541 }
 542
 543 void zd_usb_disable_int(struct zd_usb *usb)
 544 {
 545         unsigned long flags;
 546         struct zd_usb_interrupt *intr = &usb->intr;
 547         struct urb *urb;
 548
 549         spin_lock_irqsave(&intr->lock, flags);
 550         urb = intr->urb;
 551         if (!urb) {
 552                 spin_unlock_irqrestore(&intr->lock, flags);
 553                 return;
 554         }
 555         intr->urb = NULL;
 556         spin_unlock_irqrestore(&intr->lock, flags);
 557
 558         usb_kill_urb(urb);
 559         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
 560         usb_free_urb(urb);
 561 }
 562
 563 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
 564                              unsigned int length)
 565 {
 566         int i;
 567         struct zd_mac *mac = zd_usb_to_mac(usb);
 568         const struct rx_length_info *length_info;
 569
 570         if (length < sizeof(struct rx_length_info)) {
 571                 /* It's not a complete packet anyhow. */
 572                 return;
 573         }
 574         length_info = (struct rx_length_info *)
 575                 (buffer + length - sizeof(struct rx_length_info));
 576
 577         /* It might be that three frames are merged into a single URB
 578          * transaction. We have to check for the length info tag.
 579          *
 580          * While testing we discovered that length_info might be unaligned,
 581          * because if USB transactions are merged, the last packet will not
 582          * be padded. Unaligned access might also happen if the length_info
 583          * structure is not present.
 584          */
 585         if (get_unaligned(&length_info->tag) == cpu_to_le16(RX_LENGTH_INFO_TAG))
 586         {
 587                 unsigned int l, k, n;
 588                 for (i = 0, l = 0;; i++) {
 589                         k = le16_to_cpu(get_unaligned(&length_info->length[i]));
 590                         n = l+k;
 591                         if (n > length)
 592                                 return;
 593                         zd_mac_rx(mac, buffer+l, k);
 594                         if (i >= 2)
 595                                 return;
 596                         l = (n+3) & ~3;
 597                 }
 598         } else {
 599                 zd_mac_rx(mac, buffer, length);
 600         }
 601 }
 602
 603 static void rx_urb_complete(struct urb *urb)
 604 {
 605         struct zd_usb *usb;
 606         struct zd_usb_rx *rx;
 607         const u8 *buffer;
 608         unsigned int length;
 609
 610         switch (urb->status) {
 611         case 0:
 612                 break;
 613         case -ESHUTDOWN:
 614         case -EINVAL:
 615         case -ENODEV:
 616         case -ENOENT:
 617         case -ECONNRESET:
 618         case -EPIPE:
 619                 return;
 620         default:
 621                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 622                 goto resubmit;
 623         }
 624
 625         buffer = urb->transfer_buffer;
 626         length = urb->actual_length;
 627         usb = urb->context;
 628         rx = &usb->rx;
 629
 630         if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
 631                 /* If there is an old first fragment, we don't care. */
 632                 dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
 633                 ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
 634                 spin_lock(&rx->lock);
 635                 memcpy(rx->fragment, buffer, length);
 636                 rx->fragment_length = length;
 637                 spin_unlock(&rx->lock);
 638                 goto resubmit;
 639         }
 640
 641         spin_lock(&rx->lock);
 642         if (rx->fragment_length > 0) {
 643                 /* We are on a second fragment, we believe */
 644                 ZD_ASSERT(length + rx->fragment_length <=
 645                           ARRAY_SIZE(rx->fragment));
 646                 dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
 647                 memcpy(rx->fragment+rx->fragment_length, buffer, length);
 648                 handle_rx_packet(usb, rx->fragment,
 649                                  rx->fragment_length + length);
 650                 rx->fragment_length = 0;
 651                 spin_unlock(&rx->lock);
 652         } else {
 653                 spin_unlock(&rx->lock);
 654                 handle_rx_packet(usb, buffer, length);
 655         }
 656
 657 resubmit:
 658         usb_submit_urb(urb, GFP_ATOMIC);
 659 }
 660
 661 static struct urb *alloc_urb(struct zd_usb *usb)
 662 {
 663         struct usb_device *udev = zd_usb_to_usbdev(usb);
 664         struct urb *urb;
 665         void *buffer;
 666
 667         urb = usb_alloc_urb(0, GFP_NOFS);
 668         if (!urb)
 669                 return NULL;
 670         buffer = usb_buffer_alloc(udev, USB_MAX_RX_SIZE, GFP_NOFS,
 671                                   &urb->transfer_dma);
 672         if (!buffer) {
 673                 usb_free_urb(urb);
 674                 return NULL;
 675         }
 676
 677         usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
 678                           buffer, USB_MAX_RX_SIZE,
 679                           rx_urb_complete, usb);
 680         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 681
 682         return urb;
 683 }
 684
 685 static void free_urb(struct urb *urb)
 686 {
 687         if (!urb)
 688                 return;
 689         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 690                         urb->transfer_buffer, urb->transfer_dma);
 691         usb_free_urb(urb);
 692 }
 693
 694 int zd_usb_enable_rx(struct zd_usb *usb)
 695 {
 696         int i, r;
 697         struct zd_usb_rx *rx = &usb->rx;
 698         struct urb **urbs;
 699
 700         dev_dbg_f(zd_usb_dev(usb), "\n");
 701
 702         r = -ENOMEM;
 703         urbs = kcalloc(URBS_COUNT, sizeof(struct urb *), GFP_NOFS);
 704         if (!urbs)
 705                 goto error;
 706         for (i = 0; i < URBS_COUNT; i++) {
 707                 urbs[i] = alloc_urb(usb);
 708                 if (!urbs[i])
 709                         goto error;
 710         }
 711
 712         ZD_ASSERT(!irqs_disabled());
 713         spin_lock_irq(&rx->lock);
 714         if (rx->urbs) {
 715                 spin_unlock_irq(&rx->lock);
 716                 r = 0;
 717                 goto error;
 718         }
 719         rx->urbs = urbs;
 720         rx->urbs_count = URBS_COUNT;
 721         spin_unlock_irq(&rx->lock);
 722
 723         for (i = 0; i < URBS_COUNT; i++) {
 724                 r = usb_submit_urb(urbs[i], GFP_NOFS);
 725                 if (r)
 726                         goto error_submit;
 727         }
 728
 729         return 0;
 730 error_submit:
 731         for (i = 0; i < URBS_COUNT; i++) {
 732                 usb_kill_urb(urbs[i]);
 733         }
 734         spin_lock_irq(&rx->lock);
 735         rx->urbs = NULL;
 736         rx->urbs_count = 0;
 737         spin_unlock_irq(&rx->lock);
 738 error:
 739         if (urbs) {
 740                 for (i = 0; i < URBS_COUNT; i++)
 741                         free_urb(urbs[i]);
 742         }
 743         return r;
 744 }
 745
 746 void zd_usb_disable_rx(struct zd_usb *usb)
 747 {
 748         int i;
 749         unsigned long flags;
 750         struct urb **urbs;
 751         unsigned int count;
 752         struct zd_usb_rx *rx = &usb->rx;
 753
 754         spin_lock_irqsave(&rx->lock, flags);
 755         urbs = rx->urbs;
 756         count = rx->urbs_count;
 757         spin_unlock_irqrestore(&rx->lock, flags);
 758         if (!urbs)
 759                 return;
 760
 761         for (i = 0; i < count; i++) {
 762                 usb_kill_urb(urbs[i]);
 763                 free_urb(urbs[i]);
 764         }
 765         kfree(urbs);
 766
 767         spin_lock_irqsave(&rx->lock, flags);
 768         rx->urbs = NULL;
 769         rx->urbs_count = 0;
 770         spin_unlock_irqrestore(&rx->lock, flags);
 771 }
 772
 773 static void tx_urb_complete(struct urb *urb)
 774 {
 775         int r;
 776
 777         switch (urb->status) {
 778         case 0:
 779                 break;
 780         case -ESHUTDOWN:
 781         case -EINVAL:
 782         case -ENODEV:
 783         case -ENOENT:
 784         case -ECONNRESET:
 785         case -EPIPE:
 786                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 787                 break;
 788         default:
 789                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 790                 goto resubmit;
 791         }
 792 free_urb:
 793         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 794                         urb->transfer_buffer, urb->transfer_dma);
 795         usb_free_urb(urb);
 796         return;
 797 resubmit:
 798         r = usb_submit_urb(urb, GFP_ATOMIC);
 799         if (r) {
 800                 dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
 801                 goto free_urb;
 802         }
 803 }
 804
 805 /* Puts the frame on the USB endpoint. It doesn't wait for
 806  * completion. The frame must contain the control set.
 807  */
 808 int zd_usb_tx(struct zd_usb *usb, const u8 *frame, unsigned int length)
 809 {
 810         int r;
 811         struct usb_device *udev = zd_usb_to_usbdev(usb);
 812         struct urb *urb;
 813         void *buffer;
 814
 815         urb = usb_alloc_urb(0, GFP_ATOMIC);
 816         if (!urb) {
 817                 r = -ENOMEM;
 818                 goto out;
 819         }
 820
 821         buffer = usb_buffer_alloc(zd_usb_to_usbdev(usb), length, GFP_ATOMIC,
 822                                   &urb->transfer_dma);
 823         if (!buffer) {
 824                 r = -ENOMEM;
 825                 goto error_free_urb;
 826         }
 827         memcpy(buffer, frame, length);
 828
 829         usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
 830                           buffer, length, tx_urb_complete, NULL);
 831         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 832
 833         r = usb_submit_urb(urb, GFP_ATOMIC);
 834         if (r)
 835                 goto error;
 836         return 0;
 837 error:
 838         usb_buffer_free(zd_usb_to_usbdev(usb), length, buffer,
 839                         urb->transfer_dma);
 840 error_free_urb:
 841         usb_free_urb(urb);
 842 out:
 843         return r;
 844 }
 845
 846 static inline void init_usb_interrupt(struct zd_usb *usb)
 847 {
 848         struct zd_usb_interrupt *intr = &usb->intr;
 849
 850         spin_lock_init(&intr->lock);
 851         intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
 852         init_completion(&intr->read_regs.completion);
 853         intr->read_regs.cr_int_addr = cpu_to_le16(usb_addr(usb, CR_INTERRUPT));
 854 }
 855
 856 static inline void init_usb_rx(struct zd_usb *usb)
 857 {
 858         struct zd_usb_rx *rx = &usb->rx;
 859         spin_lock_init(&rx->lock);
 860         if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
 861                 rx->usb_packet_size = 512;
 862         } else {
 863                 rx->usb_packet_size = 64;
 864         }
 865         ZD_ASSERT(rx->fragment_length == 0);
 866 }
 867
 868 static inline void init_usb_tx(struct zd_usb *usb)
 869 {
 870         /* FIXME: at this point we will allocate a fixed number of urb's for
 871          * use in a cyclic scheme */
 872 }
 873
 874 void zd_usb_init(struct zd_usb *usb, struct net_device *netdev,
 875                  struct usb_interface *intf)
 876 {
 877         memset(usb, 0, sizeof(*usb));
 878         usb->intf = usb_get_intf(intf);
 879         usb_set_intfdata(usb->intf, netdev);
 880         init_usb_interrupt(usb);
 881         init_usb_tx(usb);
 882         init_usb_rx(usb);
 883 }
 884
 885 int zd_usb_init_hw(struct zd_usb *usb)
 886 {
 887         int r;
 888         struct zd_chip *chip = zd_usb_to_chip(usb);
 889
 890         ZD_ASSERT(mutex_is_locked(&chip->mutex));
 891         r = zd_ioread16_locked(chip, &usb->fw_base_offset,
 892                         USB_REG((u16)FW_BASE_ADDR_OFFSET));
 893         if (r)
 894                 return r;
 895         dev_dbg_f(zd_usb_dev(usb), "fw_base_offset: %#06hx\n",
 896                  usb->fw_base_offset);
 897
 898         return 0;
 899 }
 900
 901 void zd_usb_clear(struct zd_usb *usb)
 902 {
 903         usb_set_intfdata(usb->intf, NULL);
 904         usb_put_intf(usb->intf);
 905         ZD_MEMCLEAR(usb, sizeof(*usb));
 906         /* FIXME: usb_interrupt, usb_tx, usb_rx? */
 907 }
 908
 909 static const char *speed(enum usb_device_speed speed)
 910 {
 911         switch (speed) {
 912         case USB_SPEED_LOW:
 913                 return "low";
 914         case USB_SPEED_FULL:
 915                 return "full";
 916         case USB_SPEED_HIGH:
 917                 return "high";
 918         default:
 919                 return "unknown speed";
 920         }
 921 }
 922
 923 static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
 924 {
 925         return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
 926                 le16_to_cpu(udev->descriptor.idVendor),
 927                 le16_to_cpu(udev->descriptor.idProduct),
 928                 get_bcdDevice(udev),
 929                 speed(udev->speed));
 930 }
 931
 932 int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
 933 {
 934         struct usb_device *udev = interface_to_usbdev(usb->intf);
 935         return scnprint_id(udev, buffer, size);
 936 }
 937
 938 #ifdef DEBUG
 939 static void print_id(struct usb_device *udev)
 940 {
 941         char buffer[40];
 942
 943         scnprint_id(udev, buffer, sizeof(buffer));
 944         buffer[sizeof(buffer)-1] = 0;
 945         dev_dbg_f(&udev->dev, "%s\n", buffer);
 946 }
 947 #else
 948 #define print_id(udev) do { } while (0)
 949 #endif
 950
 951 static int eject_installer(struct usb_interface *intf)
 952 {
 953         struct usb_device *udev = interface_to_usbdev(intf);
 954         struct usb_host_interface *iface_desc = &intf->altsetting[0];
 955         struct usb_endpoint_descriptor *endpoint;
 956         unsigned char *cmd;
 957         u8 bulk_out_ep;
 958         int r;
 959
 960         /* Find bulk out endpoint */
 961         endpoint = &iface_desc->endpoint[1].desc;
 962         if ((endpoint->bEndpointAddress & USB_TYPE_MASK) == USB_DIR_OUT &&
 963             (endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
 964             USB_ENDPOINT_XFER_BULK) {
 965                 bulk_out_ep = endpoint->bEndpointAddress;
 966         } else {
 967                 dev_err(&udev->dev,
 968                         "zd1211rw: Could not find bulk out endpoint\n");
 969                 return -ENODEV;
 970         }
 971
 972         cmd = kzalloc(31, GFP_KERNEL);
 973         if (cmd == NULL)
 974                 return -ENODEV;
 975
 976         /* USB bulk command block */
 977         cmd[0] = 0x55;  /* bulk command signature */
 978         cmd[1] = 0x53;  /* bulk command signature */
 979         cmd[2] = 0x42;  /* bulk command signature */
 980         cmd[3] = 0x43;  /* bulk command signature */
 981         cmd[14] = 6;    /* command length */
 982
 983         cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
 984         cmd[19] = 0x2;  /* eject disc */
 985
 986         dev_info(&udev->dev, "Ejecting virtual installer media...\n");
 987         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
 988                 cmd, 31, NULL, 2000);
 989         kfree(cmd);
 990         if (r)
 991                 return r;
 992
 993         /* At this point, the device disconnects and reconnects with the real
 994          * ID numbers. */
 995
 996         usb_set_intfdata(intf, NULL);
 997         return 0;
 998 }
 999
1000 static int probe(struct usb_interface *intf, const struct usb_device_id *id)
1001 {
1002         int r;
1003         struct usb_device *udev = interface_to_usbdev(intf);
1004         struct net_device *netdev = NULL;
1005
1006         print_id(udev);
1007
1008         if (id->driver_info & DEVICE_INSTALLER)
1009                 return eject_installer(intf);
1010
1011         switch (udev->speed) {
1012         case USB_SPEED_LOW:
1013         case USB_SPEED_FULL:
1014         case USB_SPEED_HIGH:
1015                 break;
1016         default:
1017                 dev_dbg_f(&intf->dev, "Unknown USB speed\n");
1018                 r = -ENODEV;
1019                 goto error;
1020         }
1021
1022         netdev = zd_netdev_alloc(intf);
1023         if (netdev == NULL) {
1024                 r = -ENOMEM;
1025                 goto error;
1026         }
1027
1028         r = upload_firmware(udev, id->driver_info);
1029         if (r) {
1030                 dev_err(&intf->dev,
1031                        "couldn't load firmware. Error number %d\n", r);
1032                 goto error;
1033         }
1034
1035         r = usb_reset_configuration(udev);
1036         if (r) {
1037                 dev_dbg_f(&intf->dev,
1038                         "couldn't reset configuration. Error number %d\n", r);
1039                 goto error;
1040         }
1041
1042         /* At this point the interrupt endpoint is not generally enabled. We
1043          * save the USB bandwidth until the network device is opened. But
1044          * notify that the initialization of the MAC will require the
1045          * interrupts to be temporary enabled.
1046          */
1047         r = zd_mac_init_hw(zd_netdev_mac(netdev), id->driver_info);
1048         if (r) {
1049                 dev_dbg_f(&intf->dev,
1050                          "couldn't initialize mac. Error number %d\n", r);
1051                 goto error;
1052         }
1053
1054         r = register_netdev(netdev);
1055         if (r) {
1056                 dev_dbg_f(&intf->dev,
1057                          "couldn't register netdev. Error number %d\n", r);
1058                 goto error;
1059         }
1060
1061         dev_dbg_f(&intf->dev, "successful\n");
1062         dev_info(&intf->dev,"%s\n", netdev->name);
1063         return 0;
1064 error:
1065         usb_reset_device(interface_to_usbdev(intf));
1066         zd_netdev_free(netdev);
1067         return r;
1068 }
1069
1070 static void disconnect(struct usb_interface *intf)
1071 {
1072         struct net_device *netdev = zd_intf_to_netdev(intf);
1073         struct zd_mac *mac = zd_netdev_mac(netdev);
1074         struct zd_usb *usb = &mac->chip.usb;
1075
1076         /* Either something really bad happened, or we're just dealing with
1077          * a DEVICE_INSTALLER. */
1078         if (netdev == NULL)
1079                 return;
1080
1081         dev_dbg_f(zd_usb_dev(usb), "\n");
1082
1083         zd_netdev_disconnect(netdev);
1084
1085         /* Just in case something has gone wrong! */
1086         zd_usb_disable_rx(usb);
1087         zd_usb_disable_int(usb);
1088
1089         /* If the disconnect has been caused by a removal of the
1090          * driver module, the reset allows reloading of the driver. If the
1091          * reset will not be executed here, the upload of the firmware in the
1092          * probe function caused by the reloading of the driver will fail.
1093          */
1094         usb_reset_device(interface_to_usbdev(intf));
1095
1096         zd_netdev_free(netdev);
1097         dev_dbg(&intf->dev, "disconnected\n");
1098 }
1099
1100 static struct usb_driver driver = {
1101         .name           = "zd1211rw",
1102         .id_table       = usb_ids,
1103         .probe          = probe,
1104         .disconnect     = disconnect,
1105 };
1106
1107 struct workqueue_struct *zd_workqueue;
1108
1109 static int __init usb_init(void)
1110 {
1111         int r;
1112
1113         pr_debug("usb_init()\n");
1114
1115         zd_workqueue = create_singlethread_workqueue(driver.name);
1116         if (zd_workqueue == NULL) {
1117                 printk(KERN_ERR "%s: couldn't create workqueue\n", driver.name);
1118                 return -ENOMEM;
1119         }
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         destroy_workqueue(zd_workqueue);
1136 }
1137
1138 module_init(usb_init);
1139 module_exit(usb_exit);
1140
1141 static int usb_int_regs_length(unsigned int count)
1142 {
1143         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1144 }
1145
1146 static void prepare_read_regs_int(struct zd_usb *usb)
1147 {
1148         struct zd_usb_interrupt *intr = &usb->intr;
1149
1150         spin_lock_irq(&intr->lock);
1151         intr->read_regs_enabled = 1;
1152         INIT_COMPLETION(intr->read_regs.completion);
1153         spin_unlock_irq(&intr->lock);
1154 }
1155
1156 static void disable_read_regs_int(struct zd_usb *usb)
1157 {
1158         struct zd_usb_interrupt *intr = &usb->intr;
1159
1160         spin_lock_irq(&intr->lock);
1161         intr->read_regs_enabled = 0;
1162         spin_unlock_irq(&intr->lock);
1163 }
1164
1165 static int get_results(struct zd_usb *usb, u16 *values,
1166                        struct usb_req_read_regs *req, unsigned int count)
1167 {
1168         int r;
1169         int i;
1170         struct zd_usb_interrupt *intr = &usb->intr;
1171         struct read_regs_int *rr = &intr->read_regs;
1172         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1173
1174         spin_lock_irq(&intr->lock);
1175
1176         r = -EIO;
1177         /* The created block size seems to be larger than expected.
1178          * However results appear to be correct.
1179          */
1180         if (rr->length < usb_int_regs_length(count)) {
1181                 dev_dbg_f(zd_usb_dev(usb),
1182                          "error: actual length %d less than expected %d\n",
1183                          rr->length, usb_int_regs_length(count));
1184                 goto error_unlock;
1185         }
1186         if (rr->length > sizeof(rr->buffer)) {
1187                 dev_dbg_f(zd_usb_dev(usb),
1188                          "error: actual length %d exceeds buffer size %zu\n",
1189                          rr->length, sizeof(rr->buffer));
1190                 goto error_unlock;
1191         }
1192
1193         for (i = 0; i < count; i++) {
1194                 struct reg_data *rd = &regs->regs[i];
1195                 if (rd->addr != req->addr[i]) {
1196                         dev_dbg_f(zd_usb_dev(usb),
1197                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1198                                  le16_to_cpu(rd->addr),
1199                                  le16_to_cpu(req->addr[i]));
1200                         goto error_unlock;
1201                 }
1202                 values[i] = le16_to_cpu(rd->value);
1203         }
1204
1205         r = 0;
1206 error_unlock:
1207         spin_unlock_irq(&intr->lock);
1208         return r;
1209 }
1210
1211 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1212                      const zd_addr_t *addresses, unsigned int count)
1213 {
1214         int r;
1215         int i, req_len, actual_req_len;
1216         struct usb_device *udev;
1217         struct usb_req_read_regs *req = NULL;
1218         unsigned long timeout;
1219
1220         if (count < 1) {
1221                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1222                 return -EINVAL;
1223         }
1224         if (count > USB_MAX_IOREAD16_COUNT) {
1225                 dev_dbg_f(zd_usb_dev(usb),
1226                          "error: count %u exceeds possible max %u\n",
1227                          count, USB_MAX_IOREAD16_COUNT);
1228                 return -EINVAL;
1229         }
1230         if (in_atomic()) {
1231                 dev_dbg_f(zd_usb_dev(usb),
1232                          "error: io in atomic context not supported\n");
1233                 return -EWOULDBLOCK;
1234         }
1235         if (!usb_int_enabled(usb)) {
1236                  dev_dbg_f(zd_usb_dev(usb),
1237                           "error: usb interrupt not enabled\n");
1238                 return -EWOULDBLOCK;
1239         }
1240
1241         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1242         req = kmalloc(req_len, GFP_NOFS);
1243         if (!req)
1244                 return -ENOMEM;
1245         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1246         for (i = 0; i < count; i++)
1247                 req->addr[i] = cpu_to_le16(usb_addr(usb, addresses[i]));
1248
1249         udev = zd_usb_to_usbdev(usb);
1250         prepare_read_regs_int(usb);
1251         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1252                          req, req_len, &actual_req_len, 1000 /* ms */);
1253         if (r) {
1254                 dev_dbg_f(zd_usb_dev(usb),
1255                         "error in usb_bulk_msg(). Error number %d\n", r);
1256                 goto error;
1257         }
1258         if (req_len != actual_req_len) {
1259                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()\n"
1260                         " req_len %d != actual_req_len %d\n",
1261                         req_len, actual_req_len);
1262                 r = -EIO;
1263                 goto error;
1264         }
1265
1266         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1267                                               msecs_to_jiffies(1000));
1268         if (!timeout) {
1269                 disable_read_regs_int(usb);
1270                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1271                 r = -ETIMEDOUT;
1272                 goto error;
1273         }
1274
1275         r = get_results(usb, values, req, count);
1276 error:
1277         kfree(req);
1278         return r;
1279 }
1280
1281 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1282                       unsigned int count)
1283 {
1284         int r;
1285         struct usb_device *udev;
1286         struct usb_req_write_regs *req = NULL;
1287         int i, req_len, actual_req_len;
1288
1289         if (count == 0)
1290                 return 0;
1291         if (count > USB_MAX_IOWRITE16_COUNT) {
1292                 dev_dbg_f(zd_usb_dev(usb),
1293                         "error: count %u exceeds possible max %u\n",
1294                         count, USB_MAX_IOWRITE16_COUNT);
1295                 return -EINVAL;
1296         }
1297         if (in_atomic()) {
1298                 dev_dbg_f(zd_usb_dev(usb),
1299                         "error: io in atomic context not supported\n");
1300                 return -EWOULDBLOCK;
1301         }
1302
1303         req_len = sizeof(struct usb_req_write_regs) +
1304                   count * sizeof(struct reg_data);
1305         req = kmalloc(req_len, GFP_NOFS);
1306         if (!req)
1307                 return -ENOMEM;
1308
1309         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1310         for (i = 0; i < count; i++) {
1311                 struct reg_data *rw  = &req->reg_writes[i];
1312                 rw->addr = cpu_to_le16(usb_addr(usb, ioreqs[i].addr));
1313                 rw->value = cpu_to_le16(ioreqs[i].value);
1314         }
1315
1316         udev = zd_usb_to_usbdev(usb);
1317         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1318                          req, req_len, &actual_req_len, 1000 /* ms */);
1319         if (r) {
1320                 dev_dbg_f(zd_usb_dev(usb),
1321                         "error in usb_bulk_msg(). Error number %d\n", r);
1322                 goto error;
1323         }
1324         if (req_len != actual_req_len) {
1325                 dev_dbg_f(zd_usb_dev(usb),
1326                         "error in usb_bulk_msg()"
1327                         " req_len %d != actual_req_len %d\n",
1328                         req_len, actual_req_len);
1329                 r = -EIO;
1330                 goto error;
1331         }
1332
1333         /* FALL-THROUGH with r == 0 */
1334 error:
1335         kfree(req);
1336         return r;
1337 }
1338
1339 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1340 {
1341         int r;
1342         struct usb_device *udev;
1343         struct usb_req_rfwrite *req = NULL;
1344         int i, req_len, actual_req_len;
1345         u16 bit_value_template;
1346
1347         if (in_atomic()) {
1348                 dev_dbg_f(zd_usb_dev(usb),
1349                         "error: io in atomic context not supported\n");
1350                 return -EWOULDBLOCK;
1351         }
1352         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1353                 dev_dbg_f(zd_usb_dev(usb),
1354                         "error: bits %d are smaller than"
1355                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1356                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1357                 return -EINVAL;
1358         }
1359         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1360                 dev_dbg_f(zd_usb_dev(usb),
1361                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1362                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1363                 return -EINVAL;
1364         }
1365 #ifdef DEBUG
1366         if (value & (~0UL << bits)) {
1367                 dev_dbg_f(zd_usb_dev(usb),
1368                         "error: value %#09x has bits >= %d set\n",
1369                         value, bits);
1370                 return -EINVAL;
1371         }
1372 #endif /* DEBUG */
1373
1374         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1375
1376         r = zd_usb_ioread16(usb, &bit_value_template, CR203);
1377         if (r) {
1378                 dev_dbg_f(zd_usb_dev(usb),
1379                         "error %d: Couldn't read CR203\n", r);
1380                 goto out;
1381         }
1382         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1383
1384         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1385         req = kmalloc(req_len, GFP_NOFS);
1386         if (!req)
1387                 return -ENOMEM;
1388
1389         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1390         /* 1: 3683a, but not used in ZYDAS driver */
1391         req->value = cpu_to_le16(2);
1392         req->bits = cpu_to_le16(bits);
1393
1394         for (i = 0; i < bits; i++) {
1395                 u16 bv = bit_value_template;
1396                 if (value & (1 << (bits-1-i)))
1397                         bv |= RF_DATA;
1398                 req->bit_values[i] = cpu_to_le16(bv);
1399         }
1400
1401         udev = zd_usb_to_usbdev(usb);
1402         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1403                          req, req_len, &actual_req_len, 1000 /* ms */);
1404         if (r) {
1405                 dev_dbg_f(zd_usb_dev(usb),
1406                         "error in usb_bulk_msg(). Error number %d\n", r);
1407                 goto out;
1408         }
1409         if (req_len != actual_req_len) {
1410                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()"
1411                         " req_len %d != actual_req_len %d\n",
1412                         req_len, actual_req_len);
1413                 r = -EIO;
1414                 goto out;
1415         }
1416
1417         /* FALL-THROUGH with r == 0 */
1418 out:
1419         kfree(req);
1420         return r;
1421 }