drivers/net/wireless/zd1211rw/zd_usb.c

   1 /* ZD1211 USB-WLAN driver for Linux
   2  *
   3  * Copyright (C) 2005-2007 Ulrich Kunitz <kune@deine-taler.de>
   4  * Copyright (C) 2006-2007 Daniel Drake <dsd@gentoo.org>
   5  * Copyright (C) 2006-2007 Michael Wu <flamingice@sourmilk.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20  */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/init.h>
  24 #include <linux/firmware.h>
  25 #include <linux/device.h>
  26 #include <linux/errno.h>
  27 #include <linux/skbuff.h>
  28 #include <linux/usb.h>
  29 #include <linux/workqueue.h>
  30 #include <net/mac80211.h>
  31 #include <asm/unaligned.h>
  32
  33 #include "zd_def.h"
  34 #include "zd_mac.h"
  35 #include "zd_usb.h"
  36
  37 static struct usb_device_id usb_ids[] = {
  38         /* ZD1211 */
  39         { USB_DEVICE(0x0ace, 0x1211), .driver_info = DEVICE_ZD1211 },
  40         { USB_DEVICE(0x0ace, 0xa211), .driver_info = DEVICE_ZD1211 },
  41         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211 },
  42         { USB_DEVICE(0x126f, 0xa006), .driver_info = DEVICE_ZD1211 },
  43         { USB_DEVICE(0x6891, 0xa727), .driver_info = DEVICE_ZD1211 },
  44         { USB_DEVICE(0x0df6, 0x9071), .driver_info = DEVICE_ZD1211 },
  45         { USB_DEVICE(0x0df6, 0x9075), .driver_info = DEVICE_ZD1211 },
  46         { USB_DEVICE(0x157e, 0x300b), .driver_info = DEVICE_ZD1211 },
  47         { USB_DEVICE(0x079b, 0x004a), .driver_info = DEVICE_ZD1211 },
  48         { USB_DEVICE(0x1740, 0x2000), .driver_info = DEVICE_ZD1211 },
  49         { USB_DEVICE(0x157e, 0x3204), .driver_info = DEVICE_ZD1211 },
  50         { USB_DEVICE(0x0586, 0x3402), .driver_info = DEVICE_ZD1211 },
  51         { USB_DEVICE(0x0b3b, 0x5630), .driver_info = DEVICE_ZD1211 },
  52         { USB_DEVICE(0x0b05, 0x170c), .driver_info = DEVICE_ZD1211 },
  53         { USB_DEVICE(0x1435, 0x0711), .driver_info = DEVICE_ZD1211 },
  54         { USB_DEVICE(0x0586, 0x3409), .driver_info = DEVICE_ZD1211 },
  55         { USB_DEVICE(0x0b3b, 0x1630), .driver_info = DEVICE_ZD1211 },
  56         { USB_DEVICE(0x0586, 0x3401), .driver_info = DEVICE_ZD1211 },
  57         { USB_DEVICE(0x14ea, 0xab13), .driver_info = DEVICE_ZD1211 },
  58         { USB_DEVICE(0x13b1, 0x001e), .driver_info = DEVICE_ZD1211 },
  59         { USB_DEVICE(0x0586, 0x3407), .driver_info = DEVICE_ZD1211 },
  60         { USB_DEVICE(0x129b, 0x1666), .driver_info = DEVICE_ZD1211 },
  61         { USB_DEVICE(0x157e, 0x300a), .driver_info = DEVICE_ZD1211 },
  62         { USB_DEVICE(0x0105, 0x145f), .driver_info = DEVICE_ZD1211 },
  63         /* ZD1211B */
  64         { USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
  65         { USB_DEVICE(0x0ace, 0xb215), .driver_info = DEVICE_ZD1211B },
  66         { USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
  67         { USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
  68         { USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
  69         { USB_DEVICE(0x050d, 0x705c), .driver_info = DEVICE_ZD1211B },
  70         { USB_DEVICE(0x083a, 0xe503), .driver_info = DEVICE_ZD1211B },
  71         { USB_DEVICE(0x083a, 0xe506), .driver_info = DEVICE_ZD1211B },
  72         { USB_DEVICE(0x083a, 0x4505), .driver_info = DEVICE_ZD1211B },
  73         { USB_DEVICE(0x0471, 0x1236), .driver_info = DEVICE_ZD1211B },
  74         { USB_DEVICE(0x13b1, 0x0024), .driver_info = DEVICE_ZD1211B },
  75         { USB_DEVICE(0x0586, 0x340f), .driver_info = DEVICE_ZD1211B },
  76         { USB_DEVICE(0x0b05, 0x171b), .driver_info = DEVICE_ZD1211B },
  77         { USB_DEVICE(0x0586, 0x3410), .driver_info = DEVICE_ZD1211B },
  78         { USB_DEVICE(0x0baf, 0x0121), .driver_info = DEVICE_ZD1211B },
  79         { USB_DEVICE(0x0586, 0x3412), .driver_info = DEVICE_ZD1211B },
  80         { USB_DEVICE(0x0586, 0x3413), .driver_info = DEVICE_ZD1211B },
  81         { USB_DEVICE(0x0053, 0x5301), .driver_info = DEVICE_ZD1211B },
  82         { USB_DEVICE(0x0411, 0x00da), .driver_info = DEVICE_ZD1211B },
  83         { USB_DEVICE(0x2019, 0x5303), .driver_info = DEVICE_ZD1211B },
  84         { USB_DEVICE(0x129b, 0x1667), .driver_info = DEVICE_ZD1211B },
  85         { USB_DEVICE(0x0cde, 0x001a), .driver_info = DEVICE_ZD1211B },
  86         { USB_DEVICE(0x0586, 0x340a), .driver_info = DEVICE_ZD1211B },
  87         { USB_DEVICE(0x0471, 0x1237), .driver_info = DEVICE_ZD1211B },
  88         { USB_DEVICE(0x07fa, 0x1196), .driver_info = DEVICE_ZD1211B },
  89         { USB_DEVICE(0x0df6, 0x0036), .driver_info = DEVICE_ZD1211B },
  90         /* "Driverless" devices that need ejecting */
  91         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
  92         { USB_DEVICE(0x0ace, 0x20ff), .driver_info = DEVICE_INSTALLER },
  93         {}
  94 };
  95
  96 MODULE_LICENSE("GPL");
  97 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
  98 MODULE_AUTHOR("Ulrich Kunitz");
  99 MODULE_AUTHOR("Daniel Drake");
 100 MODULE_VERSION("1.0");
 101 MODULE_DEVICE_TABLE(usb, usb_ids);
 102
 103 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
 104 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
 105
 106 /* USB device initialization */
 107 static void int_urb_complete(struct urb *urb);
 108
 109 static int request_fw_file(
 110         const struct firmware **fw, const char *name, struct device *device)
 111 {
 112         int r;
 113
 114         dev_dbg_f(device, "fw name %s\n", name);
 115
 116         r = request_firmware(fw, name, device);
 117         if (r)
 118                 dev_err(device,
 119                        "Could not load firmware file %s. Error number %d\n",
 120                        name, r);
 121         return r;
 122 }
 123
 124 static inline u16 get_bcdDevice(const struct usb_device *udev)
 125 {
 126         return le16_to_cpu(udev->descriptor.bcdDevice);
 127 }
 128
 129 enum upload_code_flags {
 130         REBOOT = 1,
 131 };
 132
 133 /* Ensures that MAX_TRANSFER_SIZE is even. */
 134 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
 135
 136 static int upload_code(struct usb_device *udev,
 137         const u8 *data, size_t size, u16 code_offset, int flags)
 138 {
 139         u8 *p;
 140         int r;
 141
 142         /* USB request blocks need "kmalloced" buffers.
 143          */
 144         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
 145         if (!p) {
 146                 dev_err(&udev->dev, "out of memory\n");
 147                 r = -ENOMEM;
 148                 goto error;
 149         }
 150
 151         size &= ~1;
 152         while (size > 0) {
 153                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
 154                         size : MAX_TRANSFER_SIZE;
 155
 156                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
 157
 158                 memcpy(p, data, transfer_size);
 159                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 160                         USB_REQ_FIRMWARE_DOWNLOAD,
 161                         USB_DIR_OUT | USB_TYPE_VENDOR,
 162                         code_offset, 0, p, transfer_size, 1000 /* ms */);
 163                 if (r < 0) {
 164                         dev_err(&udev->dev,
 165                                "USB control request for firmware upload"
 166                                " failed. Error number %d\n", r);
 167                         goto error;
 168                 }
 169                 transfer_size = r & ~1;
 170
 171                 size -= transfer_size;
 172                 data += transfer_size;
 173                 code_offset += transfer_size/sizeof(u16);
 174         }
 175
 176         if (flags & REBOOT) {
 177                 u8 ret;
 178
 179                 /* Use "DMA-aware" buffer. */
 180                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 181                         USB_REQ_FIRMWARE_CONFIRM,
 182                         USB_DIR_IN | USB_TYPE_VENDOR,
 183                         0, 0, p, sizeof(ret), 5000 /* ms */);
 184                 if (r != sizeof(ret)) {
 185                         dev_err(&udev->dev,
 186                                 "control request firmeware confirmation failed."
 187                                 " Return value %d\n", r);
 188                         if (r >= 0)
 189                                 r = -ENODEV;
 190                         goto error;
 191                 }
 192                 ret = p[0];
 193                 if (ret & 0x80) {
 194                         dev_err(&udev->dev,
 195                                 "Internal error while downloading."
 196                                 " Firmware confirm return value %#04x\n",
 197                                 (unsigned int)ret);
 198                         r = -ENODEV;
 199                         goto error;
 200                 }
 201                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
 202                         (unsigned int)ret);
 203         }
 204
 205         r = 0;
 206 error:
 207         kfree(p);
 208         return r;
 209 }
 210
 211 static u16 get_word(const void *data, u16 offset)
 212 {
 213         const __le16 *p = data;
 214         return le16_to_cpu(p[offset]);
 215 }
 216
 217 static char *get_fw_name(struct zd_usb *usb, char *buffer, size_t size,
 218                        const char* postfix)
 219 {
 220         scnprintf(buffer, size, "%s%s",
 221                 usb->is_zd1211b ?
 222                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
 223                 postfix);
 224         return buffer;
 225 }
 226
 227 static int handle_version_mismatch(struct zd_usb *usb,
 228         const struct firmware *ub_fw)
 229 {
 230         struct usb_device *udev = zd_usb_to_usbdev(usb);
 231         const struct firmware *ur_fw = NULL;
 232         int offset;
 233         int r = 0;
 234         char fw_name[128];
 235
 236         r = request_fw_file(&ur_fw,
 237                 get_fw_name(usb, fw_name, sizeof(fw_name), "ur"),
 238                 &udev->dev);
 239         if (r)
 240                 goto error;
 241
 242         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START, REBOOT);
 243         if (r)
 244                 goto error;
 245
 246         offset = (E2P_BOOT_CODE_OFFSET * sizeof(u16));
 247         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
 248                 E2P_START + E2P_BOOT_CODE_OFFSET, REBOOT);
 249
 250         /* At this point, the vendor driver downloads the whole firmware
 251          * image, hacks around with version IDs, and uploads it again,
 252          * completely overwriting the boot code. We do not do this here as
 253          * it is not required on any tested devices, and it is suspected to
 254          * cause problems. */
 255 error:
 256         release_firmware(ur_fw);
 257         return r;
 258 }
 259
 260 static int upload_firmware(struct zd_usb *usb)
 261 {
 262         int r;
 263         u16 fw_bcdDevice;
 264         u16 bcdDevice;
 265         struct usb_device *udev = zd_usb_to_usbdev(usb);
 266         const struct firmware *ub_fw = NULL;
 267         const struct firmware *uph_fw = NULL;
 268         char fw_name[128];
 269
 270         bcdDevice = get_bcdDevice(udev);
 271
 272         r = request_fw_file(&ub_fw,
 273                 get_fw_name(usb, fw_name, sizeof(fw_name), "ub"),
 274                 &udev->dev);
 275         if (r)
 276                 goto error;
 277
 278         fw_bcdDevice = get_word(ub_fw->data, E2P_DATA_OFFSET);
 279
 280         if (fw_bcdDevice != bcdDevice) {
 281                 dev_info(&udev->dev,
 282                         "firmware version %#06x and device bootcode version "
 283                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
 284                 if (bcdDevice <= 0x4313)
 285                         dev_warn(&udev->dev, "device has old bootcode, please "
 286                                 "report success or failure\n");
 287
 288                 r = handle_version_mismatch(usb, ub_fw);
 289                 if (r)
 290                         goto error;
 291         } else {
 292                 dev_dbg_f(&udev->dev,
 293                         "firmware device id %#06x is equal to the "
 294                         "actual device id\n", fw_bcdDevice);
 295         }
 296
 297
 298         r = request_fw_file(&uph_fw,
 299                 get_fw_name(usb, fw_name, sizeof(fw_name), "uphr"),
 300                 &udev->dev);
 301         if (r)
 302                 goto error;
 303
 304         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START, REBOOT);
 305         if (r) {
 306                 dev_err(&udev->dev,
 307                         "Could not upload firmware code uph. Error number %d\n",
 308                         r);
 309         }
 310
 311         /* FALL-THROUGH */
 312 error:
 313         release_firmware(ub_fw);
 314         release_firmware(uph_fw);
 315         return r;
 316 }
 317
 318 /* Read data from device address space using "firmware interface" which does
 319  * not require firmware to be loaded. */
 320 int zd_usb_read_fw(struct zd_usb *usb, zd_addr_t addr, u8 *data, u16 len)
 321 {
 322         int r;
 323         struct usb_device *udev = zd_usb_to_usbdev(usb);
 324         u8 *buf;
 325
 326         /* Use "DMA-aware" buffer. */
 327         buf = kmalloc(len, GFP_KERNEL);
 328         if (!buf)
 329                 return -ENOMEM;
 330         r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 331                 USB_REQ_FIRMWARE_READ_DATA, USB_DIR_IN | 0x40, addr, 0,
 332                 buf, len, 5000);
 333         if (r < 0) {
 334                 dev_err(&udev->dev,
 335                         "read over firmware interface failed: %d\n", r);
 336                 goto exit;
 337         } else if (r != len) {
 338                 dev_err(&udev->dev,
 339                         "incomplete read over firmware interface: %d/%d\n",
 340                         r, len);
 341                 r = -EIO;
 342                 goto exit;
 343         }
 344         r = 0;
 345         memcpy(data, buf, len);
 346 exit:
 347         kfree(buf);
 348         return r;
 349 }
 350
 351 #define urb_dev(urb) (&(urb)->dev->dev)
 352
 353 static inline void handle_regs_int(struct urb *urb)
 354 {
 355         struct zd_usb *usb = urb->context;
 356         struct zd_usb_interrupt *intr = &usb->intr;
 357         int len;
 358         u16 int_num;
 359
 360         ZD_ASSERT(in_interrupt());
 361         spin_lock(&intr->lock);
 362
 363         int_num = le16_to_cpu(*(__le16 *)(urb->transfer_buffer+2));
 364         if (int_num == CR_INTERRUPT) {
 365                 struct zd_mac *mac = zd_hw_mac(zd_usb_to_hw(urb->context));
 366                 memcpy(&mac->intr_buffer, urb->transfer_buffer,
 367                                 USB_MAX_EP_INT_BUFFER);
 368                 schedule_work(&mac->process_intr);
 369         } else if (intr->read_regs_enabled) {
 370                 intr->read_regs.length = len = urb->actual_length;
 371
 372                 if (len > sizeof(intr->read_regs.buffer))
 373                         len = sizeof(intr->read_regs.buffer);
 374                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
 375                 intr->read_regs_enabled = 0;
 376                 complete(&intr->read_regs.completion);
 377                 goto out;
 378         }
 379
 380 out:
 381         spin_unlock(&intr->lock);
 382 }
 383
 384 static void int_urb_complete(struct urb *urb)
 385 {
 386         int r;
 387         struct usb_int_header *hdr;
 388
 389         switch (urb->status) {
 390         case 0:
 391                 break;
 392         case -ESHUTDOWN:
 393         case -EINVAL:
 394         case -ENODEV:
 395         case -ENOENT:
 396         case -ECONNRESET:
 397         case -EPIPE:
 398                 goto kfree;
 399         default:
 400                 goto resubmit;
 401         }
 402
 403         if (urb->actual_length < sizeof(hdr)) {
 404                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
 405                 goto resubmit;
 406         }
 407
 408         hdr = urb->transfer_buffer;
 409         if (hdr->type != USB_INT_TYPE) {
 410                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
 411                 goto resubmit;
 412         }
 413
 414         switch (hdr->id) {
 415         case USB_INT_ID_REGS:
 416                 handle_regs_int(urb);
 417                 break;
 418         case USB_INT_ID_RETRY_FAILED:
 419                 zd_mac_tx_failed(zd_usb_to_hw(urb->context));
 420                 break;
 421         default:
 422                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
 423                         (unsigned int)hdr->id);
 424                 goto resubmit;
 425         }
 426
 427 resubmit:
 428         r = usb_submit_urb(urb, GFP_ATOMIC);
 429         if (r) {
 430                 dev_dbg_f(urb_dev(urb), "resubmit urb %p\n", urb);
 431                 goto kfree;
 432         }
 433         return;
 434 kfree:
 435         kfree(urb->transfer_buffer);
 436 }
 437
 438 static inline int int_urb_interval(struct usb_device *udev)
 439 {
 440         switch (udev->speed) {
 441         case USB_SPEED_HIGH:
 442                 return 4;
 443         case USB_SPEED_LOW:
 444                 return 10;
 445         case USB_SPEED_FULL:
 446         default:
 447                 return 1;
 448         }
 449 }
 450
 451 static inline int usb_int_enabled(struct zd_usb *usb)
 452 {
 453         unsigned long flags;
 454         struct zd_usb_interrupt *intr = &usb->intr;
 455         struct urb *urb;
 456
 457         spin_lock_irqsave(&intr->lock, flags);
 458         urb = intr->urb;
 459         spin_unlock_irqrestore(&intr->lock, flags);
 460         return urb != NULL;
 461 }
 462
 463 int zd_usb_enable_int(struct zd_usb *usb)
 464 {
 465         int r;
 466         struct usb_device *udev;
 467         struct zd_usb_interrupt *intr = &usb->intr;
 468         void *transfer_buffer = NULL;
 469         struct urb *urb;
 470
 471         dev_dbg_f(zd_usb_dev(usb), "\n");
 472
 473         urb = usb_alloc_urb(0, GFP_KERNEL);
 474         if (!urb) {
 475                 r = -ENOMEM;
 476                 goto out;
 477         }
 478
 479         ZD_ASSERT(!irqs_disabled());
 480         spin_lock_irq(&intr->lock);
 481         if (intr->urb) {
 482                 spin_unlock_irq(&intr->lock);
 483                 r = 0;
 484                 goto error_free_urb;
 485         }
 486         intr->urb = urb;
 487         spin_unlock_irq(&intr->lock);
 488
 489         /* TODO: make it a DMA buffer */
 490         r = -ENOMEM;
 491         transfer_buffer = kmalloc(USB_MAX_EP_INT_BUFFER, GFP_KERNEL);
 492         if (!transfer_buffer) {
 493                 dev_dbg_f(zd_usb_dev(usb),
 494                         "couldn't allocate transfer_buffer\n");
 495                 goto error_set_urb_null;
 496         }
 497
 498         udev = zd_usb_to_usbdev(usb);
 499         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
 500                          transfer_buffer, USB_MAX_EP_INT_BUFFER,
 501                          int_urb_complete, usb,
 502                          intr->interval);
 503
 504         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
 505         r = usb_submit_urb(urb, GFP_KERNEL);
 506         if (r) {
 507                 dev_dbg_f(zd_usb_dev(usb),
 508                          "Couldn't submit urb. Error number %d\n", r);
 509                 goto error;
 510         }
 511
 512         return 0;
 513 error:
 514         kfree(transfer_buffer);
 515 error_set_urb_null:
 516         spin_lock_irq(&intr->lock);
 517         intr->urb = NULL;
 518         spin_unlock_irq(&intr->lock);
 519 error_free_urb:
 520         usb_free_urb(urb);
 521 out:
 522         return r;
 523 }
 524
 525 void zd_usb_disable_int(struct zd_usb *usb)
 526 {
 527         unsigned long flags;
 528         struct zd_usb_interrupt *intr = &usb->intr;
 529         struct urb *urb;
 530
 531         spin_lock_irqsave(&intr->lock, flags);
 532         urb = intr->urb;
 533         if (!urb) {
 534                 spin_unlock_irqrestore(&intr->lock, flags);
 535                 return;
 536         }
 537         intr->urb = NULL;
 538         spin_unlock_irqrestore(&intr->lock, flags);
 539
 540         usb_kill_urb(urb);
 541         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
 542         usb_free_urb(urb);
 543 }
 544
 545 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
 546                              unsigned int length)
 547 {
 548         int i;
 549         const struct rx_length_info *length_info;
 550
 551         if (length < sizeof(struct rx_length_info)) {
 552                 /* It's not a complete packet anyhow. */
 553                 return;
 554         }
 555         length_info = (struct rx_length_info *)
 556                 (buffer + length - sizeof(struct rx_length_info));
 557
 558         /* It might be that three frames are merged into a single URB
 559          * transaction. We have to check for the length info tag.
 560          *
 561          * While testing we discovered that length_info might be unaligned,
 562          * because if USB transactions are merged, the last packet will not
 563          * be padded. Unaligned access might also happen if the length_info
 564          * structure is not present.
 565          */
 566         if (get_unaligned_le16(&length_info->tag) == RX_LENGTH_INFO_TAG)
 567         {
 568                 unsigned int l, k, n;
 569                 for (i = 0, l = 0;; i++) {
 570                         k = get_unaligned_le16(&length_info->length[i]);
 571                         if (k == 0)
 572                                 return;
 573                         n = l+k;
 574                         if (n > length)
 575                                 return;
 576                         zd_mac_rx(zd_usb_to_hw(usb), buffer+l, k);
 577                         if (i >= 2)
 578                                 return;
 579                         l = (n+3) & ~3;
 580                 }
 581         } else {
 582                 zd_mac_rx(zd_usb_to_hw(usb), buffer, length);
 583         }
 584 }
 585
 586 static void rx_urb_complete(struct urb *urb)
 587 {
 588         struct zd_usb *usb;
 589         struct zd_usb_rx *rx;
 590         const u8 *buffer;
 591         unsigned int length;
 592
 593         switch (urb->status) {
 594         case 0:
 595                 break;
 596         case -ESHUTDOWN:
 597         case -EINVAL:
 598         case -ENODEV:
 599         case -ENOENT:
 600         case -ECONNRESET:
 601         case -EPIPE:
 602                 return;
 603         default:
 604                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 605                 goto resubmit;
 606         }
 607
 608         buffer = urb->transfer_buffer;
 609         length = urb->actual_length;
 610         usb = urb->context;
 611         rx = &usb->rx;
 612
 613         if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
 614                 /* If there is an old first fragment, we don't care. */
 615                 dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
 616                 ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
 617                 spin_lock(&rx->lock);
 618                 memcpy(rx->fragment, buffer, length);
 619                 rx->fragment_length = length;
 620                 spin_unlock(&rx->lock);
 621                 goto resubmit;
 622         }
 623
 624         spin_lock(&rx->lock);
 625         if (rx->fragment_length > 0) {
 626                 /* We are on a second fragment, we believe */
 627                 ZD_ASSERT(length + rx->fragment_length <=
 628                           ARRAY_SIZE(rx->fragment));
 629                 dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
 630                 memcpy(rx->fragment+rx->fragment_length, buffer, length);
 631                 handle_rx_packet(usb, rx->fragment,
 632                                  rx->fragment_length + length);
 633                 rx->fragment_length = 0;
 634                 spin_unlock(&rx->lock);
 635         } else {
 636                 spin_unlock(&rx->lock);
 637                 handle_rx_packet(usb, buffer, length);
 638         }
 639
 640 resubmit:
 641         usb_submit_urb(urb, GFP_ATOMIC);
 642 }
 643
 644 static struct urb *alloc_rx_urb(struct zd_usb *usb)
 645 {
 646         struct usb_device *udev = zd_usb_to_usbdev(usb);
 647         struct urb *urb;
 648         void *buffer;
 649
 650         urb = usb_alloc_urb(0, GFP_KERNEL);
 651         if (!urb)
 652                 return NULL;
 653         buffer = usb_buffer_alloc(udev, USB_MAX_RX_SIZE, GFP_KERNEL,
 654                                   &urb->transfer_dma);
 655         if (!buffer) {
 656                 usb_free_urb(urb);
 657                 return NULL;
 658         }
 659
 660         usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
 661                           buffer, USB_MAX_RX_SIZE,
 662                           rx_urb_complete, usb);
 663         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 664
 665         return urb;
 666 }
 667
 668 static void free_rx_urb(struct urb *urb)
 669 {
 670         if (!urb)
 671                 return;
 672         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 673                         urb->transfer_buffer, urb->transfer_dma);
 674         usb_free_urb(urb);
 675 }
 676
 677 int zd_usb_enable_rx(struct zd_usb *usb)
 678 {
 679         int i, r;
 680         struct zd_usb_rx *rx = &usb->rx;
 681         struct urb **urbs;
 682
 683         dev_dbg_f(zd_usb_dev(usb), "\n");
 684
 685         r = -ENOMEM;
 686         urbs = kcalloc(RX_URBS_COUNT, sizeof(struct urb *), GFP_KERNEL);
 687         if (!urbs)
 688                 goto error;
 689         for (i = 0; i < RX_URBS_COUNT; i++) {
 690                 urbs[i] = alloc_rx_urb(usb);
 691                 if (!urbs[i])
 692                         goto error;
 693         }
 694
 695         ZD_ASSERT(!irqs_disabled());
 696         spin_lock_irq(&rx->lock);
 697         if (rx->urbs) {
 698                 spin_unlock_irq(&rx->lock);
 699                 r = 0;
 700                 goto error;
 701         }
 702         rx->urbs = urbs;
 703         rx->urbs_count = RX_URBS_COUNT;
 704         spin_unlock_irq(&rx->lock);
 705
 706         for (i = 0; i < RX_URBS_COUNT; i++) {
 707                 r = usb_submit_urb(urbs[i], GFP_KERNEL);
 708                 if (r)
 709                         goto error_submit;
 710         }
 711
 712         return 0;
 713 error_submit:
 714         for (i = 0; i < RX_URBS_COUNT; i++) {
 715                 usb_kill_urb(urbs[i]);
 716         }
 717         spin_lock_irq(&rx->lock);
 718         rx->urbs = NULL;
 719         rx->urbs_count = 0;
 720         spin_unlock_irq(&rx->lock);
 721 error:
 722         if (urbs) {
 723                 for (i = 0; i < RX_URBS_COUNT; i++)
 724                         free_rx_urb(urbs[i]);
 725         }
 726         return r;
 727 }
 728
 729 void zd_usb_disable_rx(struct zd_usb *usb)
 730 {
 731         int i;
 732         unsigned long flags;
 733         struct urb **urbs;
 734         unsigned int count;
 735         struct zd_usb_rx *rx = &usb->rx;
 736
 737         spin_lock_irqsave(&rx->lock, flags);
 738         urbs = rx->urbs;
 739         count = rx->urbs_count;
 740         spin_unlock_irqrestore(&rx->lock, flags);
 741         if (!urbs)
 742                 return;
 743
 744         for (i = 0; i < count; i++) {
 745                 usb_kill_urb(urbs[i]);
 746                 free_rx_urb(urbs[i]);
 747         }
 748         kfree(urbs);
 749
 750         spin_lock_irqsave(&rx->lock, flags);
 751         rx->urbs = NULL;
 752         rx->urbs_count = 0;
 753         spin_unlock_irqrestore(&rx->lock, flags);
 754 }
 755
 756 /**
 757  * zd_usb_disable_tx - disable transmission
 758  * @usb: the zd1211rw-private USB structure
 759  *
 760  * Frees all URBs in the free list and marks the transmission as disabled.
 761  */
 762 void zd_usb_disable_tx(struct zd_usb *usb)
 763 {
 764         struct zd_usb_tx *tx = &usb->tx;
 765         unsigned long flags;
 766         struct list_head *pos, *n;
 767
 768         spin_lock_irqsave(&tx->lock, flags);
 769         list_for_each_safe(pos, n, &tx->free_urb_list) {
 770                 list_del(pos);
 771                 usb_free_urb(list_entry(pos, struct urb, urb_list));
 772         }
 773         tx->enabled = 0;
 774         tx->submitted_urbs = 0;
 775         /* The stopped state is ignored, relying on ieee80211_wake_queues()
 776          * in a potentionally following zd_usb_enable_tx().
 777          */
 778         spin_unlock_irqrestore(&tx->lock, flags);
 779 }
 780
 781 /**
 782  * zd_usb_enable_tx - enables transmission
 783  * @usb: a &struct zd_usb pointer
 784  *
 785  * This function enables transmission and prepares the &zd_usb_tx data
 786  * structure.
 787  */
 788 void zd_usb_enable_tx(struct zd_usb *usb)
 789 {
 790         unsigned long flags;
 791         struct zd_usb_tx *tx = &usb->tx;
 792
 793         spin_lock_irqsave(&tx->lock, flags);
 794         tx->enabled = 1;
 795         tx->submitted_urbs = 0;
 796         ieee80211_wake_queues(zd_usb_to_hw(usb));
 797         tx->stopped = 0;
 798         spin_unlock_irqrestore(&tx->lock, flags);
 799 }
 800
 801 /**
 802  * alloc_tx_urb - provides an tx URB
 803  * @usb: a &struct zd_usb pointer
 804  *
 805  * Allocates a new URB. If possible takes the urb from the free list in
 806  * usb->tx.
 807  */
 808 static struct urb *alloc_tx_urb(struct zd_usb *usb)
 809 {
 810         struct zd_usb_tx *tx = &usb->tx;
 811         unsigned long flags;
 812         struct list_head *entry;
 813         struct urb *urb;
 814
 815         spin_lock_irqsave(&tx->lock, flags);
 816         if (list_empty(&tx->free_urb_list)) {
 817                 urb = usb_alloc_urb(0, GFP_ATOMIC);
 818                 goto out;
 819         }
 820         entry = tx->free_urb_list.next;
 821         list_del(entry);
 822         urb = list_entry(entry, struct urb, urb_list);
 823 out:
 824         spin_unlock_irqrestore(&tx->lock, flags);
 825         return urb;
 826 }
 827
 828 /**
 829  * free_tx_urb - frees a used tx URB
 830  * @usb: a &struct zd_usb pointer
 831  * @urb: URB to be freed
 832  *
 833  * Frees the the transmission URB, which means to put it on the free URB
 834  * list.
 835  */
 836 static void free_tx_urb(struct zd_usb *usb, struct urb *urb)
 837 {
 838         struct zd_usb_tx *tx = &usb->tx;
 839         unsigned long flags;
 840
 841         spin_lock_irqsave(&tx->lock, flags);
 842         if (!tx->enabled) {
 843                 usb_free_urb(urb);
 844                 goto out;
 845         }
 846         list_add(&urb->urb_list, &tx->free_urb_list);
 847 out:
 848         spin_unlock_irqrestore(&tx->lock, flags);
 849 }
 850
 851 static void tx_dec_submitted_urbs(struct zd_usb *usb)
 852 {
 853         struct zd_usb_tx *tx = &usb->tx;
 854         unsigned long flags;
 855
 856         spin_lock_irqsave(&tx->lock, flags);
 857         --tx->submitted_urbs;
 858         if (tx->stopped && tx->submitted_urbs <= ZD_USB_TX_LOW) {
 859                 ieee80211_wake_queues(zd_usb_to_hw(usb));
 860                 tx->stopped = 0;
 861         }
 862         spin_unlock_irqrestore(&tx->lock, flags);
 863 }
 864
 865 static void tx_inc_submitted_urbs(struct zd_usb *usb)
 866 {
 867         struct zd_usb_tx *tx = &usb->tx;
 868         unsigned long flags;
 869
 870         spin_lock_irqsave(&tx->lock, flags);
 871         ++tx->submitted_urbs;
 872         if (!tx->stopped && tx->submitted_urbs > ZD_USB_TX_HIGH) {
 873                 ieee80211_stop_queues(zd_usb_to_hw(usb));
 874                 tx->stopped = 1;
 875         }
 876         spin_unlock_irqrestore(&tx->lock, flags);
 877 }
 878
 879 /**
 880  * tx_urb_complete - completes the execution of an URB
 881  * @urb: a URB
 882  *
 883  * This function is called if the URB has been transferred to a device or an
 884  * error has happened.
 885  */
 886 static void tx_urb_complete(struct urb *urb)
 887 {
 888         int r;
 889         struct sk_buff *skb;
 890         struct ieee80211_tx_info *info;
 891         struct zd_usb *usb;
 892
 893         switch (urb->status) {
 894         case 0:
 895                 break;
 896         case -ESHUTDOWN:
 897         case -EINVAL:
 898         case -ENODEV:
 899         case -ENOENT:
 900         case -ECONNRESET:
 901         case -EPIPE:
 902                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 903                 break;
 904         default:
 905                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 906                 goto resubmit;
 907         }
 908 free_urb:
 909         skb = (struct sk_buff *)urb->context;
 910         /*
 911          * grab 'usb' pointer before handing off the skb (since
 912          * it might be freed by zd_mac_tx_to_dev or mac80211)
 913          */
 914         info = IEEE80211_SKB_CB(skb);
 915         usb = &zd_hw_mac(info->rate_driver_data[0])->chip.usb;
 916         zd_mac_tx_to_dev(skb, urb->status);
 917         free_tx_urb(usb, urb);
 918         tx_dec_submitted_urbs(usb);
 919         return;
 920 resubmit:
 921         r = usb_submit_urb(urb, GFP_ATOMIC);
 922         if (r) {
 923                 dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
 924                 goto free_urb;
 925         }
 926 }
 927
 928 /**
 929  * zd_usb_tx: initiates transfer of a frame of the device
 930  *
 931  * @usb: the zd1211rw-private USB structure
 932  * @skb: a &struct sk_buff pointer
 933  *
 934  * This function tranmits a frame to the device. It doesn't wait for
 935  * completion. The frame must contain the control set and have all the
 936  * control set information available.
 937  *
 938  * The function returns 0 if the transfer has been successfully initiated.
 939  */
 940 int zd_usb_tx(struct zd_usb *usb, struct sk_buff *skb)
 941 {
 942         int r;
 943         struct usb_device *udev = zd_usb_to_usbdev(usb);
 944         struct urb *urb;
 945
 946         urb = alloc_tx_urb(usb);
 947         if (!urb) {
 948                 r = -ENOMEM;
 949                 goto out;
 950         }
 951
 952         usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
 953                           skb->data, skb->len, tx_urb_complete, skb);
 954
 955         r = usb_submit_urb(urb, GFP_ATOMIC);
 956         if (r)
 957                 goto error;
 958         tx_inc_submitted_urbs(usb);
 959         return 0;
 960 error:
 961         free_tx_urb(usb, urb);
 962 out:
 963         return r;
 964 }
 965
 966 static inline void init_usb_interrupt(struct zd_usb *usb)
 967 {
 968         struct zd_usb_interrupt *intr = &usb->intr;
 969
 970         spin_lock_init(&intr->lock);
 971         intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
 972         init_completion(&intr->read_regs.completion);
 973         intr->read_regs.cr_int_addr = cpu_to_le16((u16)CR_INTERRUPT);
 974 }
 975
 976 static inline void init_usb_rx(struct zd_usb *usb)
 977 {
 978         struct zd_usb_rx *rx = &usb->rx;
 979         spin_lock_init(&rx->lock);
 980         if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
 981                 rx->usb_packet_size = 512;
 982         } else {
 983                 rx->usb_packet_size = 64;
 984         }
 985         ZD_ASSERT(rx->fragment_length == 0);
 986 }
 987
 988 static inline void init_usb_tx(struct zd_usb *usb)
 989 {
 990         struct zd_usb_tx *tx = &usb->tx;
 991         spin_lock_init(&tx->lock);
 992         tx->enabled = 0;
 993         tx->stopped = 0;
 994         INIT_LIST_HEAD(&tx->free_urb_list);
 995         tx->submitted_urbs = 0;
 996 }
 997
 998 void zd_usb_init(struct zd_usb *usb, struct ieee80211_hw *hw,
 999                  struct usb_interface *intf)
1000 {
1001         memset(usb, 0, sizeof(*usb));
1002         usb->intf = usb_get_intf(intf);
1003         usb_set_intfdata(usb->intf, hw);
1004         init_usb_interrupt(usb);
1005         init_usb_tx(usb);
1006         init_usb_rx(usb);
1007 }
1008
1009 void zd_usb_clear(struct zd_usb *usb)
1010 {
1011         usb_set_intfdata(usb->intf, NULL);
1012         usb_put_intf(usb->intf);
1013         ZD_MEMCLEAR(usb, sizeof(*usb));
1014         /* FIXME: usb_interrupt, usb_tx, usb_rx? */
1015 }
1016
1017 static const char *speed(enum usb_device_speed speed)
1018 {
1019         switch (speed) {
1020         case USB_SPEED_LOW:
1021                 return "low";
1022         case USB_SPEED_FULL:
1023                 return "full";
1024         case USB_SPEED_HIGH:
1025                 return "high";
1026         default:
1027                 return "unknown speed";
1028         }
1029 }
1030
1031 static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
1032 {
1033         return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
1034                 le16_to_cpu(udev->descriptor.idVendor),
1035                 le16_to_cpu(udev->descriptor.idProduct),
1036                 get_bcdDevice(udev),
1037                 speed(udev->speed));
1038 }
1039
1040 int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
1041 {
1042         struct usb_device *udev = interface_to_usbdev(usb->intf);
1043         return scnprint_id(udev, buffer, size);
1044 }
1045
1046 #ifdef DEBUG
1047 static void print_id(struct usb_device *udev)
1048 {
1049         char buffer[40];
1050
1051         scnprint_id(udev, buffer, sizeof(buffer));
1052         buffer[sizeof(buffer)-1] = 0;
1053         dev_dbg_f(&udev->dev, "%s\n", buffer);
1054 }
1055 #else
1056 #define print_id(udev) do { } while (0)
1057 #endif
1058
1059 static int eject_installer(struct usb_interface *intf)
1060 {
1061         struct usb_device *udev = interface_to_usbdev(intf);
1062         struct usb_host_interface *iface_desc = &intf->altsetting[0];
1063         struct usb_endpoint_descriptor *endpoint;
1064         unsigned char *cmd;
1065         u8 bulk_out_ep;
1066         int r;
1067
1068         /* Find bulk out endpoint */
1069         endpoint = &iface_desc->endpoint[1].desc;
1070         if ((endpoint->bEndpointAddress & USB_TYPE_MASK) == USB_DIR_OUT &&
1071             usb_endpoint_xfer_bulk(endpoint)) {
1072                 bulk_out_ep = endpoint->bEndpointAddress;
1073         } else {
1074                 dev_err(&udev->dev,
1075                         "zd1211rw: Could not find bulk out endpoint\n");
1076                 return -ENODEV;
1077         }
1078
1079         cmd = kzalloc(31, GFP_KERNEL);
1080         if (cmd == NULL)
1081                 return -ENODEV;
1082
1083         /* USB bulk command block */
1084         cmd[0] = 0x55;  /* bulk command signature */
1085         cmd[1] = 0x53;  /* bulk command signature */
1086         cmd[2] = 0x42;  /* bulk command signature */
1087         cmd[3] = 0x43;  /* bulk command signature */
1088         cmd[14] = 6;    /* command length */
1089
1090         cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
1091         cmd[19] = 0x2;  /* eject disc */
1092
1093         dev_info(&udev->dev, "Ejecting virtual installer media...\n");
1094         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
1095                 cmd, 31, NULL, 2000);
1096         kfree(cmd);
1097         if (r)
1098                 return r;
1099
1100         /* At this point, the device disconnects and reconnects with the real
1101          * ID numbers. */
1102
1103         usb_set_intfdata(intf, NULL);
1104         return 0;
1105 }
1106
1107 int zd_usb_init_hw(struct zd_usb *usb)
1108 {
1109         int r;
1110         struct zd_mac *mac = zd_usb_to_mac(usb);
1111
1112         dev_dbg_f(zd_usb_dev(usb), "\n");
1113
1114         r = upload_firmware(usb);
1115         if (r) {
1116                 dev_err(zd_usb_dev(usb),
1117                        "couldn't load firmware. Error number %d\n", r);
1118                 return r;
1119         }
1120
1121         r = usb_reset_configuration(zd_usb_to_usbdev(usb));
1122         if (r) {
1123                 dev_dbg_f(zd_usb_dev(usb),
1124                         "couldn't reset configuration. Error number %d\n", r);
1125                 return r;
1126         }
1127
1128         r = zd_mac_init_hw(mac->hw);
1129         if (r) {
1130                 dev_dbg_f(zd_usb_dev(usb),
1131                          "couldn't initialize mac. Error number %d\n", r);
1132                 return r;
1133         }
1134
1135         usb->initialized = 1;
1136         return 0;
1137 }
1138
1139 static int probe(struct usb_interface *intf, const struct usb_device_id *id)
1140 {
1141         int r;
1142         struct usb_device *udev = interface_to_usbdev(intf);
1143         struct zd_usb *usb;
1144         struct ieee80211_hw *hw = NULL;
1145
1146         print_id(udev);
1147
1148         if (id->driver_info & DEVICE_INSTALLER)
1149                 return eject_installer(intf);
1150
1151         switch (udev->speed) {
1152         case USB_SPEED_LOW:
1153         case USB_SPEED_FULL:
1154         case USB_SPEED_HIGH:
1155                 break;
1156         default:
1157                 dev_dbg_f(&intf->dev, "Unknown USB speed\n");
1158                 r = -ENODEV;
1159                 goto error;
1160         }
1161
1162         r = usb_reset_device(udev);
1163         if (r) {
1164                 dev_err(&intf->dev,
1165                         "couldn't reset usb device. Error number %d\n", r);
1166                 goto error;
1167         }
1168
1169         hw = zd_mac_alloc_hw(intf);
1170         if (hw == NULL) {
1171                 r = -ENOMEM;
1172                 goto error;
1173         }
1174
1175         usb = &zd_hw_mac(hw)->chip.usb;
1176         usb->is_zd1211b = (id->driver_info == DEVICE_ZD1211B) != 0;
1177
1178         r = zd_mac_preinit_hw(hw);
1179         if (r) {
1180                 dev_dbg_f(&intf->dev,
1181                          "couldn't initialize mac. Error number %d\n", r);
1182                 goto error;
1183         }
1184
1185         r = ieee80211_register_hw(hw);
1186         if (r) {
1187                 dev_dbg_f(&intf->dev,
1188                          "couldn't register device. Error number %d\n", r);
1189                 goto error;
1190         }
1191
1192         dev_dbg_f(&intf->dev, "successful\n");
1193         dev_info(&intf->dev, "%s\n", wiphy_name(hw->wiphy));
1194         return 0;
1195 error:
1196         usb_reset_device(interface_to_usbdev(intf));
1197         if (hw) {
1198                 zd_mac_clear(zd_hw_mac(hw));
1199                 ieee80211_free_hw(hw);
1200         }
1201         return r;
1202 }
1203
1204 static void disconnect(struct usb_interface *intf)
1205 {
1206         struct ieee80211_hw *hw = zd_intf_to_hw(intf);
1207         struct zd_mac *mac;
1208         struct zd_usb *usb;
1209
1210         /* Either something really bad happened, or we're just dealing with
1211          * a DEVICE_INSTALLER. */
1212         if (hw == NULL)
1213                 return;
1214
1215         mac = zd_hw_mac(hw);
1216         usb = &mac->chip.usb;
1217
1218         dev_dbg_f(zd_usb_dev(usb), "\n");
1219
1220         ieee80211_unregister_hw(hw);
1221
1222         /* Just in case something has gone wrong! */
1223         zd_usb_disable_rx(usb);
1224         zd_usb_disable_int(usb);
1225
1226         /* If the disconnect has been caused by a removal of the
1227          * driver module, the reset allows reloading of the driver. If the
1228          * reset will not be executed here, the upload of the firmware in the
1229          * probe function caused by the reloading of the driver will fail.
1230          */
1231         usb_reset_device(interface_to_usbdev(intf));
1232
1233         zd_mac_clear(mac);
1234         ieee80211_free_hw(hw);
1235         dev_dbg(&intf->dev, "disconnected\n");
1236 }
1237
1238 static struct usb_driver driver = {
1239         .name           = KBUILD_MODNAME,
1240         .id_table       = usb_ids,
1241         .probe          = probe,
1242         .disconnect     = disconnect,
1243 };
1244
1245 struct workqueue_struct *zd_workqueue;
1246
1247 static int __init usb_init(void)
1248 {
1249         int r;
1250
1251         pr_debug("%s usb_init()\n", driver.name);
1252
1253         zd_workqueue = create_singlethread_workqueue(driver.name);
1254         if (zd_workqueue == NULL) {
1255                 printk(KERN_ERR "%s couldn't create workqueue\n", driver.name);
1256                 return -ENOMEM;
1257         }
1258
1259         r = usb_register(&driver);
1260         if (r) {
1261                 destroy_workqueue(zd_workqueue);
1262                 printk(KERN_ERR "%s usb_register() failed. Error number %d\n",
1263                        driver.name, r);
1264                 return r;
1265         }
1266
1267         pr_debug("%s initialized\n", driver.name);
1268         return 0;
1269 }
1270
1271 static void __exit usb_exit(void)
1272 {
1273         pr_debug("%s usb_exit()\n", driver.name);
1274         usb_deregister(&driver);
1275         destroy_workqueue(zd_workqueue);
1276 }
1277
1278 module_init(usb_init);
1279 module_exit(usb_exit);
1280
1281 static int usb_int_regs_length(unsigned int count)
1282 {
1283         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1284 }
1285
1286 static void prepare_read_regs_int(struct zd_usb *usb)
1287 {
1288         struct zd_usb_interrupt *intr = &usb->intr;
1289
1290         spin_lock_irq(&intr->lock);
1291         intr->read_regs_enabled = 1;
1292         INIT_COMPLETION(intr->read_regs.completion);
1293         spin_unlock_irq(&intr->lock);
1294 }
1295
1296 static void disable_read_regs_int(struct zd_usb *usb)
1297 {
1298         struct zd_usb_interrupt *intr = &usb->intr;
1299
1300         spin_lock_irq(&intr->lock);
1301         intr->read_regs_enabled = 0;
1302         spin_unlock_irq(&intr->lock);
1303 }
1304
1305 static int get_results(struct zd_usb *usb, u16 *values,
1306                        struct usb_req_read_regs *req, unsigned int count)
1307 {
1308         int r;
1309         int i;
1310         struct zd_usb_interrupt *intr = &usb->intr;
1311         struct read_regs_int *rr = &intr->read_regs;
1312         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1313
1314         spin_lock_irq(&intr->lock);
1315
1316         r = -EIO;
1317         /* The created block size seems to be larger than expected.
1318          * However results appear to be correct.
1319          */
1320         if (rr->length < usb_int_regs_length(count)) {
1321                 dev_dbg_f(zd_usb_dev(usb),
1322                          "error: actual length %d less than expected %d\n",
1323                          rr->length, usb_int_regs_length(count));
1324                 goto error_unlock;
1325         }
1326         if (rr->length > sizeof(rr->buffer)) {
1327                 dev_dbg_f(zd_usb_dev(usb),
1328                          "error: actual length %d exceeds buffer size %zu\n",
1329                          rr->length, sizeof(rr->buffer));
1330                 goto error_unlock;
1331         }
1332
1333         for (i = 0; i < count; i++) {
1334                 struct reg_data *rd = &regs->regs[i];
1335                 if (rd->addr != req->addr[i]) {
1336                         dev_dbg_f(zd_usb_dev(usb),
1337                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1338                                  le16_to_cpu(rd->addr),
1339                                  le16_to_cpu(req->addr[i]));
1340                         goto error_unlock;
1341                 }
1342                 values[i] = le16_to_cpu(rd->value);
1343         }
1344
1345         r = 0;
1346 error_unlock:
1347         spin_unlock_irq(&intr->lock);
1348         return r;
1349 }
1350
1351 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1352                      const zd_addr_t *addresses, unsigned int count)
1353 {
1354         int r;
1355         int i, req_len, actual_req_len;
1356         struct usb_device *udev;
1357         struct usb_req_read_regs *req = NULL;
1358         unsigned long timeout;
1359
1360         if (count < 1) {
1361                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1362                 return -EINVAL;
1363         }
1364         if (count > USB_MAX_IOREAD16_COUNT) {
1365                 dev_dbg_f(zd_usb_dev(usb),
1366                          "error: count %u exceeds possible max %u\n",
1367                          count, USB_MAX_IOREAD16_COUNT);
1368                 return -EINVAL;
1369         }
1370         if (in_atomic()) {
1371                 dev_dbg_f(zd_usb_dev(usb),
1372                          "error: io in atomic context not supported\n");
1373                 return -EWOULDBLOCK;
1374         }
1375         if (!usb_int_enabled(usb)) {
1376                  dev_dbg_f(zd_usb_dev(usb),
1377                           "error: usb interrupt not enabled\n");
1378                 return -EWOULDBLOCK;
1379         }
1380
1381         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1382         req = kmalloc(req_len, GFP_KERNEL);
1383         if (!req)
1384                 return -ENOMEM;
1385         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1386         for (i = 0; i < count; i++)
1387                 req->addr[i] = cpu_to_le16((u16)addresses[i]);
1388
1389         udev = zd_usb_to_usbdev(usb);
1390         prepare_read_regs_int(usb);
1391         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1392                          req, req_len, &actual_req_len, 1000 /* ms */);
1393         if (r) {
1394                 dev_dbg_f(zd_usb_dev(usb),
1395                         "error in usb_bulk_msg(). Error number %d\n", r);
1396                 goto error;
1397         }
1398         if (req_len != actual_req_len) {
1399                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()\n"
1400                         " req_len %d != actual_req_len %d\n",
1401                         req_len, actual_req_len);
1402                 r = -EIO;
1403                 goto error;
1404         }
1405
1406         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1407                                               msecs_to_jiffies(1000));
1408         if (!timeout) {
1409                 disable_read_regs_int(usb);
1410                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1411                 r = -ETIMEDOUT;
1412                 goto error;
1413         }
1414
1415         r = get_results(usb, values, req, count);
1416 error:
1417         kfree(req);
1418         return r;
1419 }
1420
1421 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1422                       unsigned int count)
1423 {
1424         int r;
1425         struct usb_device *udev;
1426         struct usb_req_write_regs *req = NULL;
1427         int i, req_len, actual_req_len;
1428
1429         if (count == 0)
1430                 return 0;
1431         if (count > USB_MAX_IOWRITE16_COUNT) {
1432                 dev_dbg_f(zd_usb_dev(usb),
1433                         "error: count %u exceeds possible max %u\n",
1434                         count, USB_MAX_IOWRITE16_COUNT);
1435                 return -EINVAL;
1436         }
1437         if (in_atomic()) {
1438                 dev_dbg_f(zd_usb_dev(usb),
1439                         "error: io in atomic context not supported\n");
1440                 return -EWOULDBLOCK;
1441         }
1442
1443         req_len = sizeof(struct usb_req_write_regs) +
1444                   count * sizeof(struct reg_data);
1445         req = kmalloc(req_len, GFP_KERNEL);
1446         if (!req)
1447                 return -ENOMEM;
1448
1449         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1450         for (i = 0; i < count; i++) {
1451                 struct reg_data *rw  = &req->reg_writes[i];
1452                 rw->addr = cpu_to_le16((u16)ioreqs[i].addr);
1453                 rw->value = cpu_to_le16(ioreqs[i].value);
1454         }
1455
1456         udev = zd_usb_to_usbdev(usb);
1457         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1458                          req, req_len, &actual_req_len, 1000 /* ms */);
1459         if (r) {
1460                 dev_dbg_f(zd_usb_dev(usb),
1461                         "error in usb_bulk_msg(). Error number %d\n", r);
1462                 goto error;
1463         }
1464         if (req_len != actual_req_len) {
1465                 dev_dbg_f(zd_usb_dev(usb),
1466                         "error in usb_bulk_msg()"
1467                         " req_len %d != actual_req_len %d\n",
1468                         req_len, actual_req_len);
1469                 r = -EIO;
1470                 goto error;
1471         }
1472
1473         /* FALL-THROUGH with r == 0 */
1474 error:
1475         kfree(req);
1476         return r;
1477 }
1478
1479 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1480 {
1481         int r;
1482         struct usb_device *udev;
1483         struct usb_req_rfwrite *req = NULL;
1484         int i, req_len, actual_req_len;
1485         u16 bit_value_template;
1486
1487         if (in_atomic()) {
1488                 dev_dbg_f(zd_usb_dev(usb),
1489                         "error: io in atomic context not supported\n");
1490                 return -EWOULDBLOCK;
1491         }
1492         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1493                 dev_dbg_f(zd_usb_dev(usb),
1494                         "error: bits %d are smaller than"
1495                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1496                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1497                 return -EINVAL;
1498         }
1499         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1500                 dev_dbg_f(zd_usb_dev(usb),
1501                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1502                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1503                 return -EINVAL;
1504         }
1505 #ifdef DEBUG
1506         if (value & (~0UL << bits)) {
1507                 dev_dbg_f(zd_usb_dev(usb),
1508                         "error: value %#09x has bits >= %d set\n",
1509                         value, bits);
1510                 return -EINVAL;
1511         }
1512 #endif /* DEBUG */
1513
1514         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1515
1516         r = zd_usb_ioread16(usb, &bit_value_template, CR203);
1517         if (r) {
1518                 dev_dbg_f(zd_usb_dev(usb),
1519                         "error %d: Couldn't read CR203\n", r);
1520                 goto out;
1521         }
1522         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1523
1524         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1525         req = kmalloc(req_len, GFP_KERNEL);
1526         if (!req)
1527                 return -ENOMEM;
1528
1529         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1530         /* 1: 3683a, but not used in ZYDAS driver */
1531         req->value = cpu_to_le16(2);
1532         req->bits = cpu_to_le16(bits);
1533
1534         for (i = 0; i < bits; i++) {
1535                 u16 bv = bit_value_template;
1536                 if (value & (1 << (bits-1-i)))
1537                         bv |= RF_DATA;
1538                 req->bit_values[i] = cpu_to_le16(bv);
1539         }
1540
1541         udev = zd_usb_to_usbdev(usb);
1542         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1543                          req, req_len, &actual_req_len, 1000 /* ms */);
1544         if (r) {
1545                 dev_dbg_f(zd_usb_dev(usb),
1546                         "error in usb_bulk_msg(). Error number %d\n", r);
1547                 goto out;
1548         }
1549         if (req_len != actual_req_len) {
1550                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()"
1551                         " req_len %d != actual_req_len %d\n",
1552                         req_len, actual_req_len);
1553                 r = -EIO;
1554                 goto out;
1555         }
1556
1557         /* FALL-THROUGH with r == 0 */
1558 out:
1559         kfree(req);
1560         return r;
1561 }