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/slab.h>
  28 #include <linux/skbuff.h>
  29 #include <linux/usb.h>
  30 #include <linux/workqueue.h>
  31 #include <net/mac80211.h>
  32 #include <asm/unaligned.h>
  33
  34 #include "zd_def.h"
  35 #include "zd_mac.h"
  36 #include "zd_usb.h"
  37
  38 static struct usb_device_id usb_ids[] = {
  39         /* ZD1211 */
  40         { USB_DEVICE(0x0105, 0x145f), .driver_info = DEVICE_ZD1211 },
  41         { USB_DEVICE(0x0586, 0x3401), .driver_info = DEVICE_ZD1211 },
  42         { USB_DEVICE(0x0586, 0x3402), .driver_info = DEVICE_ZD1211 },
  43         { USB_DEVICE(0x0586, 0x3407), .driver_info = DEVICE_ZD1211 },
  44         { USB_DEVICE(0x0586, 0x3409), .driver_info = DEVICE_ZD1211 },
  45         { USB_DEVICE(0x079b, 0x004a), .driver_info = DEVICE_ZD1211 },
  46         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211 },
  47         { USB_DEVICE(0x0ace, 0x1211), .driver_info = DEVICE_ZD1211 },
  48         { USB_DEVICE(0x0ace, 0xa211), .driver_info = DEVICE_ZD1211 },
  49         { USB_DEVICE(0x0b05, 0x170c), .driver_info = DEVICE_ZD1211 },
  50         { USB_DEVICE(0x0b3b, 0x1630), .driver_info = DEVICE_ZD1211 },
  51         { USB_DEVICE(0x0b3b, 0x5630), .driver_info = DEVICE_ZD1211 },
  52         { USB_DEVICE(0x0df6, 0x9071), .driver_info = DEVICE_ZD1211 },
  53         { USB_DEVICE(0x0df6, 0x9075), .driver_info = DEVICE_ZD1211 },
  54         { USB_DEVICE(0x126f, 0xa006), .driver_info = DEVICE_ZD1211 },
  55         { USB_DEVICE(0x129b, 0x1666), .driver_info = DEVICE_ZD1211 },
  56         { USB_DEVICE(0x13b1, 0x001e), .driver_info = DEVICE_ZD1211 },
  57         { USB_DEVICE(0x1435, 0x0711), .driver_info = DEVICE_ZD1211 },
  58         { USB_DEVICE(0x14ea, 0xab10), .driver_info = DEVICE_ZD1211 },
  59         { USB_DEVICE(0x14ea, 0xab13), .driver_info = DEVICE_ZD1211 },
  60         { USB_DEVICE(0x157e, 0x300a), .driver_info = DEVICE_ZD1211 },
  61         { USB_DEVICE(0x157e, 0x300b), .driver_info = DEVICE_ZD1211 },
  62         { USB_DEVICE(0x157e, 0x3204), .driver_info = DEVICE_ZD1211 },
  63         { USB_DEVICE(0x157e, 0x3207), .driver_info = DEVICE_ZD1211 },
  64         { USB_DEVICE(0x1740, 0x2000), .driver_info = DEVICE_ZD1211 },
  65         { USB_DEVICE(0x6891, 0xa727), .driver_info = DEVICE_ZD1211 },
  66         /* ZD1211B */
  67         { USB_DEVICE(0x0053, 0x5301), .driver_info = DEVICE_ZD1211B },
  68         { USB_DEVICE(0x0409, 0x0248), .driver_info = DEVICE_ZD1211B },
  69         { USB_DEVICE(0x0411, 0x00da), .driver_info = DEVICE_ZD1211B },
  70         { USB_DEVICE(0x0471, 0x1236), .driver_info = DEVICE_ZD1211B },
  71         { USB_DEVICE(0x0471, 0x1237), .driver_info = DEVICE_ZD1211B },
  72         { USB_DEVICE(0x050d, 0x705c), .driver_info = DEVICE_ZD1211B },
  73         { USB_DEVICE(0x054c, 0x0257), .driver_info = DEVICE_ZD1211B },
  74         { USB_DEVICE(0x0586, 0x340a), .driver_info = DEVICE_ZD1211B },
  75         { USB_DEVICE(0x0586, 0x340f), .driver_info = DEVICE_ZD1211B },
  76         { USB_DEVICE(0x0586, 0x3410), .driver_info = DEVICE_ZD1211B },
  77         { USB_DEVICE(0x0586, 0x3412), .driver_info = DEVICE_ZD1211B },
  78         { USB_DEVICE(0x0586, 0x3413), .driver_info = DEVICE_ZD1211B },
  79         { USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
  80         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211B },
  81         { USB_DEVICE(0x07fa, 0x1196), .driver_info = DEVICE_ZD1211B },
  82         { USB_DEVICE(0x083a, 0x4505), .driver_info = DEVICE_ZD1211B },
  83         { USB_DEVICE(0x083a, 0xe501), .driver_info = DEVICE_ZD1211B },
  84         { USB_DEVICE(0x083a, 0xe503), .driver_info = DEVICE_ZD1211B },
  85         { USB_DEVICE(0x083a, 0xe506), .driver_info = DEVICE_ZD1211B },
  86         { USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
  87         { USB_DEVICE(0x0ace, 0xb215), .driver_info = DEVICE_ZD1211B },
  88         { USB_DEVICE(0x0b05, 0x171b), .driver_info = DEVICE_ZD1211B },
  89         { USB_DEVICE(0x0baf, 0x0121), .driver_info = DEVICE_ZD1211B },
  90         { USB_DEVICE(0x0cde, 0x001a), .driver_info = DEVICE_ZD1211B },
  91         { USB_DEVICE(0x0df6, 0x0036), .driver_info = DEVICE_ZD1211B },
  92         { USB_DEVICE(0x129b, 0x1667), .driver_info = DEVICE_ZD1211B },
  93         { USB_DEVICE(0x13b1, 0x0024), .driver_info = DEVICE_ZD1211B },
  94         { USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
  95         { USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
  96         { USB_DEVICE(0x2019, 0x5303), .driver_info = DEVICE_ZD1211B },
  97         { USB_DEVICE(0x2019, 0xed01), .driver_info = DEVICE_ZD1211B },
  98         /* "Driverless" devices that need ejecting */
  99         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
 100         { USB_DEVICE(0x0ace, 0x20ff), .driver_info = DEVICE_INSTALLER },
 101         {}
 102 };
 103
 104 MODULE_LICENSE("GPL");
 105 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
 106 MODULE_AUTHOR("Ulrich Kunitz");
 107 MODULE_AUTHOR("Daniel Drake");
 108 MODULE_VERSION("1.0");
 109 MODULE_DEVICE_TABLE(usb, usb_ids);
 110
 111 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
 112 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
 113
 114 /* USB device initialization */
 115 static void int_urb_complete(struct urb *urb);
 116
 117 static int request_fw_file(
 118         const struct firmware **fw, const char *name, struct device *device)
 119 {
 120         int r;
 121
 122         dev_dbg_f(device, "fw name %s\n", name);
 123
 124         r = request_firmware(fw, name, device);
 125         if (r)
 126                 dev_err(device,
 127                        "Could not load firmware file %s. Error number %d\n",
 128                        name, r);
 129         return r;
 130 }
 131
 132 static inline u16 get_bcdDevice(const struct usb_device *udev)
 133 {
 134         return le16_to_cpu(udev->descriptor.bcdDevice);
 135 }
 136
 137 enum upload_code_flags {
 138         REBOOT = 1,
 139 };
 140
 141 /* Ensures that MAX_TRANSFER_SIZE is even. */
 142 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
 143
 144 static int upload_code(struct usb_device *udev,
 145         const u8 *data, size_t size, u16 code_offset, int flags)
 146 {
 147         u8 *p;
 148         int r;
 149
 150         /* USB request blocks need "kmalloced" buffers.
 151          */
 152         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
 153         if (!p) {
 154                 dev_err(&udev->dev, "out of memory\n");
 155                 r = -ENOMEM;
 156                 goto error;
 157         }
 158
 159         size &= ~1;
 160         while (size > 0) {
 161                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
 162                         size : MAX_TRANSFER_SIZE;
 163
 164                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
 165
 166                 memcpy(p, data, transfer_size);
 167                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 168                         USB_REQ_FIRMWARE_DOWNLOAD,
 169                         USB_DIR_OUT | USB_TYPE_VENDOR,
 170                         code_offset, 0, p, transfer_size, 1000 /* ms */);
 171                 if (r < 0) {
 172                         dev_err(&udev->dev,
 173                                "USB control request for firmware upload"
 174                                " failed. Error number %d\n", r);
 175                         goto error;
 176                 }
 177                 transfer_size = r & ~1;
 178
 179                 size -= transfer_size;
 180                 data += transfer_size;
 181                 code_offset += transfer_size/sizeof(u16);
 182         }
 183
 184         if (flags & REBOOT) {
 185                 u8 ret;
 186
 187                 /* Use "DMA-aware" buffer. */
 188                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 189                         USB_REQ_FIRMWARE_CONFIRM,
 190                         USB_DIR_IN | USB_TYPE_VENDOR,
 191                         0, 0, p, sizeof(ret), 5000 /* ms */);
 192                 if (r != sizeof(ret)) {
 193                         dev_err(&udev->dev,
 194                                 "control request firmeware confirmation failed."
 195                                 " Return value %d\n", r);
 196                         if (r >= 0)
 197                                 r = -ENODEV;
 198                         goto error;
 199                 }
 200                 ret = p[0];
 201                 if (ret & 0x80) {
 202                         dev_err(&udev->dev,
 203                                 "Internal error while downloading."
 204                                 " Firmware confirm return value %#04x\n",
 205                                 (unsigned int)ret);
 206                         r = -ENODEV;
 207                         goto error;
 208                 }
 209                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
 210                         (unsigned int)ret);
 211         }
 212
 213         r = 0;
 214 error:
 215         kfree(p);
 216         return r;
 217 }
 218
 219 static u16 get_word(const void *data, u16 offset)
 220 {
 221         const __le16 *p = data;
 222         return le16_to_cpu(p[offset]);
 223 }
 224
 225 static char *get_fw_name(struct zd_usb *usb, char *buffer, size_t size,
 226                        const char* postfix)
 227 {
 228         scnprintf(buffer, size, "%s%s",
 229                 usb->is_zd1211b ?
 230                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
 231                 postfix);
 232         return buffer;
 233 }
 234
 235 static int handle_version_mismatch(struct zd_usb *usb,
 236         const struct firmware *ub_fw)
 237 {
 238         struct usb_device *udev = zd_usb_to_usbdev(usb);
 239         const struct firmware *ur_fw = NULL;
 240         int offset;
 241         int r = 0;
 242         char fw_name[128];
 243
 244         r = request_fw_file(&ur_fw,
 245                 get_fw_name(usb, fw_name, sizeof(fw_name), "ur"),
 246                 &udev->dev);
 247         if (r)
 248                 goto error;
 249
 250         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START, REBOOT);
 251         if (r)
 252                 goto error;
 253
 254         offset = (E2P_BOOT_CODE_OFFSET * sizeof(u16));
 255         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
 256                 E2P_START + E2P_BOOT_CODE_OFFSET, REBOOT);
 257
 258         /* At this point, the vendor driver downloads the whole firmware
 259          * image, hacks around with version IDs, and uploads it again,
 260          * completely overwriting the boot code. We do not do this here as
 261          * it is not required on any tested devices, and it is suspected to
 262          * cause problems. */
 263 error:
 264         release_firmware(ur_fw);
 265         return r;
 266 }
 267
 268 static int upload_firmware(struct zd_usb *usb)
 269 {
 270         int r;
 271         u16 fw_bcdDevice;
 272         u16 bcdDevice;
 273         struct usb_device *udev = zd_usb_to_usbdev(usb);
 274         const struct firmware *ub_fw = NULL;
 275         const struct firmware *uph_fw = NULL;
 276         char fw_name[128];
 277
 278         bcdDevice = get_bcdDevice(udev);
 279
 280         r = request_fw_file(&ub_fw,
 281                 get_fw_name(usb, fw_name, sizeof(fw_name), "ub"),
 282                 &udev->dev);
 283         if (r)
 284                 goto error;
 285
 286         fw_bcdDevice = get_word(ub_fw->data, E2P_DATA_OFFSET);
 287
 288         if (fw_bcdDevice != bcdDevice) {
 289                 dev_info(&udev->dev,
 290                         "firmware version %#06x and device bootcode version "
 291                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
 292                 if (bcdDevice <= 0x4313)
 293                         dev_warn(&udev->dev, "device has old bootcode, please "
 294                                 "report success or failure\n");
 295
 296                 r = handle_version_mismatch(usb, ub_fw);
 297                 if (r)
 298                         goto error;
 299         } else {
 300                 dev_dbg_f(&udev->dev,
 301                         "firmware device id %#06x is equal to the "
 302                         "actual device id\n", fw_bcdDevice);
 303         }
 304
 305
 306         r = request_fw_file(&uph_fw,
 307                 get_fw_name(usb, fw_name, sizeof(fw_name), "uphr"),
 308                 &udev->dev);
 309         if (r)
 310                 goto error;
 311
 312         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START, REBOOT);
 313         if (r) {
 314                 dev_err(&udev->dev,
 315                         "Could not upload firmware code uph. Error number %d\n",
 316                         r);
 317         }
 318
 319         /* FALL-THROUGH */
 320 error:
 321         release_firmware(ub_fw);
 322         release_firmware(uph_fw);
 323         return r;
 324 }
 325
 326 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "ur");
 327 MODULE_FIRMWARE(FW_ZD1211_PREFIX "ur");
 328 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "ub");
 329 MODULE_FIRMWARE(FW_ZD1211_PREFIX "ub");
 330 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "uphr");
 331 MODULE_FIRMWARE(FW_ZD1211_PREFIX "uphr");
 332
 333 /* Read data from device address space using "firmware interface" which does
 334  * not require firmware to be loaded. */
 335 int zd_usb_read_fw(struct zd_usb *usb, zd_addr_t addr, u8 *data, u16 len)
 336 {
 337         int r;
 338         struct usb_device *udev = zd_usb_to_usbdev(usb);
 339         u8 *buf;
 340
 341         /* Use "DMA-aware" buffer. */
 342         buf = kmalloc(len, GFP_KERNEL);
 343         if (!buf)
 344                 return -ENOMEM;
 345         r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 346                 USB_REQ_FIRMWARE_READ_DATA, USB_DIR_IN | 0x40, addr, 0,
 347                 buf, len, 5000);
 348         if (r < 0) {
 349                 dev_err(&udev->dev,
 350                         "read over firmware interface failed: %d\n", r);
 351                 goto exit;
 352         } else if (r != len) {
 353                 dev_err(&udev->dev,
 354                         "incomplete read over firmware interface: %d/%d\n",
 355                         r, len);
 356                 r = -EIO;
 357                 goto exit;
 358         }
 359         r = 0;
 360         memcpy(data, buf, len);
 361 exit:
 362         kfree(buf);
 363         return r;
 364 }
 365
 366 #define urb_dev(urb) (&(urb)->dev->dev)
 367
 368 static inline void handle_regs_int(struct urb *urb)
 369 {
 370         struct zd_usb *usb = urb->context;
 371         struct zd_usb_interrupt *intr = &usb->intr;
 372         int len;
 373         u16 int_num;
 374
 375         ZD_ASSERT(in_interrupt());
 376         spin_lock(&intr->lock);
 377
 378         int_num = le16_to_cpu(*(__le16 *)(urb->transfer_buffer+2));
 379         if (int_num == CR_INTERRUPT) {
 380                 struct zd_mac *mac = zd_hw_mac(zd_usb_to_hw(urb->context));
 381                 spin_lock(&mac->lock);
 382                 memcpy(&mac->intr_buffer, urb->transfer_buffer,
 383                                 USB_MAX_EP_INT_BUFFER);
 384                 spin_unlock(&mac->lock);
 385                 schedule_work(&mac->process_intr);
 386         } else if (intr->read_regs_enabled) {
 387                 intr->read_regs.length = len = urb->actual_length;
 388
 389                 if (len > sizeof(intr->read_regs.buffer))
 390                         len = sizeof(intr->read_regs.buffer);
 391                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
 392                 intr->read_regs_enabled = 0;
 393                 complete(&intr->read_regs.completion);
 394                 goto out;
 395         }
 396
 397 out:
 398         spin_unlock(&intr->lock);
 399 }
 400
 401 static void int_urb_complete(struct urb *urb)
 402 {
 403         int r;
 404         struct usb_int_header *hdr;
 405
 406         switch (urb->status) {
 407         case 0:
 408                 break;
 409         case -ESHUTDOWN:
 410         case -EINVAL:
 411         case -ENODEV:
 412         case -ENOENT:
 413         case -ECONNRESET:
 414         case -EPIPE:
 415                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 416                 return;
 417         default:
 418                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 419                 goto resubmit;
 420         }
 421
 422         if (urb->actual_length < sizeof(hdr)) {
 423                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
 424                 goto resubmit;
 425         }
 426
 427         hdr = urb->transfer_buffer;
 428         if (hdr->type != USB_INT_TYPE) {
 429                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
 430                 goto resubmit;
 431         }
 432
 433         switch (hdr->id) {
 434         case USB_INT_ID_REGS:
 435                 handle_regs_int(urb);
 436                 break;
 437         case USB_INT_ID_RETRY_FAILED:
 438                 zd_mac_tx_failed(urb);
 439                 break;
 440         default:
 441                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
 442                         (unsigned int)hdr->id);
 443                 goto resubmit;
 444         }
 445
 446 resubmit:
 447         r = usb_submit_urb(urb, GFP_ATOMIC);
 448         if (r) {
 449                 dev_dbg_f(urb_dev(urb), "error: resubmit urb %p err code %d\n",
 450                           urb, r);
 451                 /* TODO: add worker to reset intr->urb */
 452         }
 453         return;
 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 = zd_usb_to_usbdev(usb);
 485         struct zd_usb_interrupt *intr = &usb->intr;
 486         struct urb *urb;
 487
 488         dev_dbg_f(zd_usb_dev(usb), "\n");
 489
 490         urb = usb_alloc_urb(0, GFP_KERNEL);
 491         if (!urb) {
 492                 r = -ENOMEM;
 493                 goto out;
 494         }
 495
 496         ZD_ASSERT(!irqs_disabled());
 497         spin_lock_irq(&intr->lock);
 498         if (intr->urb) {
 499                 spin_unlock_irq(&intr->lock);
 500                 r = 0;
 501                 goto error_free_urb;
 502         }
 503         intr->urb = urb;
 504         spin_unlock_irq(&intr->lock);
 505
 506         r = -ENOMEM;
 507         intr->buffer = usb_alloc_coherent(udev, USB_MAX_EP_INT_BUFFER,
 508                                           GFP_KERNEL, &intr->buffer_dma);
 509         if (!intr->buffer) {
 510                 dev_dbg_f(zd_usb_dev(usb),
 511                         "couldn't allocate transfer_buffer\n");
 512                 goto error_set_urb_null;
 513         }
 514
 515         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
 516                          intr->buffer, USB_MAX_EP_INT_BUFFER,
 517                          int_urb_complete, usb,
 518                          intr->interval);
 519         urb->transfer_dma = intr->buffer_dma;
 520         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 521
 522         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
 523         r = usb_submit_urb(urb, GFP_KERNEL);
 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         usb_free_coherent(udev, USB_MAX_EP_INT_BUFFER,
 533                           intr->buffer, intr->buffer_dma);
 534 error_set_urb_null:
 535         spin_lock_irq(&intr->lock);
 536         intr->urb = NULL;
 537         spin_unlock_irq(&intr->lock);
 538 error_free_urb:
 539         usb_free_urb(urb);
 540 out:
 541         return r;
 542 }
 543
 544 void zd_usb_disable_int(struct zd_usb *usb)
 545 {
 546         unsigned long flags;
 547         struct usb_device *udev = zd_usb_to_usbdev(usb);
 548         struct zd_usb_interrupt *intr = &usb->intr;
 549         struct urb *urb;
 550         void *buffer;
 551         dma_addr_t buffer_dma;
 552
 553         spin_lock_irqsave(&intr->lock, flags);
 554         urb = intr->urb;
 555         if (!urb) {
 556                 spin_unlock_irqrestore(&intr->lock, flags);
 557                 return;
 558         }
 559         intr->urb = NULL;
 560         buffer = intr->buffer;
 561         buffer_dma = intr->buffer_dma;
 562         intr->buffer = NULL;
 563         spin_unlock_irqrestore(&intr->lock, flags);
 564
 565         usb_kill_urb(urb);
 566         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
 567         usb_free_urb(urb);
 568
 569         if (buffer)
 570                 usb_free_coherent(udev, USB_MAX_EP_INT_BUFFER,
 571                                   buffer, buffer_dma);
 572 }
 573
 574 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
 575                              unsigned int length)
 576 {
 577         int i;
 578         const struct rx_length_info *length_info;
 579
 580         if (length < sizeof(struct rx_length_info)) {
 581                 /* It's not a complete packet anyhow. */
 582                 printk("%s: invalid, small RX packet : %d\n",
 583                        __func__, length);
 584                 return;
 585         }
 586         length_info = (struct rx_length_info *)
 587                 (buffer + length - sizeof(struct rx_length_info));
 588
 589         /* It might be that three frames are merged into a single URB
 590          * transaction. We have to check for the length info tag.
 591          *
 592          * While testing we discovered that length_info might be unaligned,
 593          * because if USB transactions are merged, the last packet will not
 594          * be padded. Unaligned access might also happen if the length_info
 595          * structure is not present.
 596          */
 597         if (get_unaligned_le16(&length_info->tag) == RX_LENGTH_INFO_TAG)
 598         {
 599                 unsigned int l, k, n;
 600                 for (i = 0, l = 0;; i++) {
 601                         k = get_unaligned_le16(&length_info->length[i]);
 602                         if (k == 0)
 603                                 return;
 604                         n = l+k;
 605                         if (n > length)
 606                                 return;
 607                         zd_mac_rx(zd_usb_to_hw(usb), buffer+l, k);
 608                         if (i >= 2)
 609                                 return;
 610                         l = (n+3) & ~3;
 611                 }
 612         } else {
 613                 zd_mac_rx(zd_usb_to_hw(usb), buffer, length);
 614         }
 615 }
 616
 617 static void rx_urb_complete(struct urb *urb)
 618 {
 619         int r;
 620         struct zd_usb *usb;
 621         struct zd_usb_rx *rx;
 622         const u8 *buffer;
 623         unsigned int length;
 624
 625         switch (urb->status) {
 626         case 0:
 627                 break;
 628         case -ESHUTDOWN:
 629         case -EINVAL:
 630         case -ENODEV:
 631         case -ENOENT:
 632         case -ECONNRESET:
 633         case -EPIPE:
 634                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 635                 return;
 636         default:
 637                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 638                 goto resubmit;
 639         }
 640
 641         buffer = urb->transfer_buffer;
 642         length = urb->actual_length;
 643         usb = urb->context;
 644         rx = &usb->rx;
 645
 646         zd_usb_reset_rx_idle_timer(usb);
 647
 648         if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
 649                 /* If there is an old first fragment, we don't care. */
 650                 dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
 651                 ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
 652                 spin_lock(&rx->lock);
 653                 memcpy(rx->fragment, buffer, length);
 654                 rx->fragment_length = length;
 655                 spin_unlock(&rx->lock);
 656                 goto resubmit;
 657         }
 658
 659         spin_lock(&rx->lock);
 660         if (rx->fragment_length > 0) {
 661                 /* We are on a second fragment, we believe */
 662                 ZD_ASSERT(length + rx->fragment_length <=
 663                           ARRAY_SIZE(rx->fragment));
 664                 dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
 665                 memcpy(rx->fragment+rx->fragment_length, buffer, length);
 666                 handle_rx_packet(usb, rx->fragment,
 667                                  rx->fragment_length + length);
 668                 rx->fragment_length = 0;
 669                 spin_unlock(&rx->lock);
 670         } else {
 671                 spin_unlock(&rx->lock);
 672                 handle_rx_packet(usb, buffer, length);
 673         }
 674
 675 resubmit:
 676         r = usb_submit_urb(urb, GFP_ATOMIC);
 677         if (r)
 678                 dev_dbg_f(urb_dev(urb), "urb %p resubmit error %d\n", urb, r);
 679 }
 680
 681 static struct urb *alloc_rx_urb(struct zd_usb *usb)
 682 {
 683         struct usb_device *udev = zd_usb_to_usbdev(usb);
 684         struct urb *urb;
 685         void *buffer;
 686
 687         urb = usb_alloc_urb(0, GFP_KERNEL);
 688         if (!urb)
 689                 return NULL;
 690         buffer = usb_alloc_coherent(udev, USB_MAX_RX_SIZE, GFP_KERNEL,
 691                                     &urb->transfer_dma);
 692         if (!buffer) {
 693                 usb_free_urb(urb);
 694                 return NULL;
 695         }
 696
 697         usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
 698                           buffer, USB_MAX_RX_SIZE,
 699                           rx_urb_complete, usb);
 700         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 701
 702         return urb;
 703 }
 704
 705 static void free_rx_urb(struct urb *urb)
 706 {
 707         if (!urb)
 708                 return;
 709         usb_free_coherent(urb->dev, urb->transfer_buffer_length,
 710                           urb->transfer_buffer, urb->transfer_dma);
 711         usb_free_urb(urb);
 712 }
 713
 714 static int __zd_usb_enable_rx(struct zd_usb *usb)
 715 {
 716         int i, r;
 717         struct zd_usb_rx *rx = &usb->rx;
 718         struct urb **urbs;
 719
 720         dev_dbg_f(zd_usb_dev(usb), "\n");
 721
 722         r = -ENOMEM;
 723         urbs = kcalloc(RX_URBS_COUNT, sizeof(struct urb *), GFP_KERNEL);
 724         if (!urbs)
 725                 goto error;
 726         for (i = 0; i < RX_URBS_COUNT; i++) {
 727                 urbs[i] = alloc_rx_urb(usb);
 728                 if (!urbs[i])
 729                         goto error;
 730         }
 731
 732         ZD_ASSERT(!irqs_disabled());
 733         spin_lock_irq(&rx->lock);
 734         if (rx->urbs) {
 735                 spin_unlock_irq(&rx->lock);
 736                 r = 0;
 737                 goto error;
 738         }
 739         rx->urbs = urbs;
 740         rx->urbs_count = RX_URBS_COUNT;
 741         spin_unlock_irq(&rx->lock);
 742
 743         for (i = 0; i < RX_URBS_COUNT; i++) {
 744                 r = usb_submit_urb(urbs[i], GFP_KERNEL);
 745                 if (r)
 746                         goto error_submit;
 747         }
 748
 749         return 0;
 750 error_submit:
 751         for (i = 0; i < RX_URBS_COUNT; i++) {
 752                 usb_kill_urb(urbs[i]);
 753         }
 754         spin_lock_irq(&rx->lock);
 755         rx->urbs = NULL;
 756         rx->urbs_count = 0;
 757         spin_unlock_irq(&rx->lock);
 758 error:
 759         if (urbs) {
 760                 for (i = 0; i < RX_URBS_COUNT; i++)
 761                         free_rx_urb(urbs[i]);
 762         }
 763         return r;
 764 }
 765
 766 int zd_usb_enable_rx(struct zd_usb *usb)
 767 {
 768         int r;
 769         struct zd_usb_rx *rx = &usb->rx;
 770
 771         mutex_lock(&rx->setup_mutex);
 772         r = __zd_usb_enable_rx(usb);
 773         mutex_unlock(&rx->setup_mutex);
 774
 775         zd_usb_reset_rx_idle_timer(usb);
 776
 777         return r;
 778 }
 779
 780 static void __zd_usb_disable_rx(struct zd_usb *usb)
 781 {
 782         int i;
 783         unsigned long flags;
 784         struct urb **urbs;
 785         unsigned int count;
 786         struct zd_usb_rx *rx = &usb->rx;
 787
 788         spin_lock_irqsave(&rx->lock, flags);
 789         urbs = rx->urbs;
 790         count = rx->urbs_count;
 791         spin_unlock_irqrestore(&rx->lock, flags);
 792         if (!urbs)
 793                 return;
 794
 795         for (i = 0; i < count; i++) {
 796                 usb_kill_urb(urbs[i]);
 797                 free_rx_urb(urbs[i]);
 798         }
 799         kfree(urbs);
 800
 801         spin_lock_irqsave(&rx->lock, flags);
 802         rx->urbs = NULL;
 803         rx->urbs_count = 0;
 804         spin_unlock_irqrestore(&rx->lock, flags);
 805 }
 806
 807 void zd_usb_disable_rx(struct zd_usb *usb)
 808 {
 809         struct zd_usb_rx *rx = &usb->rx;
 810
 811         mutex_lock(&rx->setup_mutex);
 812         __zd_usb_disable_rx(usb);
 813         mutex_unlock(&rx->setup_mutex);
 814
 815         cancel_delayed_work_sync(&rx->idle_work);
 816 }
 817
 818 static void zd_usb_reset_rx(struct zd_usb *usb)
 819 {
 820         bool do_reset;
 821         struct zd_usb_rx *rx = &usb->rx;
 822         unsigned long flags;
 823
 824         mutex_lock(&rx->setup_mutex);
 825
 826         spin_lock_irqsave(&rx->lock, flags);
 827         do_reset = rx->urbs != NULL;
 828         spin_unlock_irqrestore(&rx->lock, flags);
 829
 830         if (do_reset) {
 831                 __zd_usb_disable_rx(usb);
 832                 __zd_usb_enable_rx(usb);
 833         }
 834
 835         mutex_unlock(&rx->setup_mutex);
 836
 837         if (do_reset)
 838                 zd_usb_reset_rx_idle_timer(usb);
 839 }
 840
 841 /**
 842  * zd_usb_disable_tx - disable transmission
 843  * @usb: the zd1211rw-private USB structure
 844  *
 845  * Frees all URBs in the free list and marks the transmission as disabled.
 846  */
 847 void zd_usb_disable_tx(struct zd_usb *usb)
 848 {
 849         struct zd_usb_tx *tx = &usb->tx;
 850         unsigned long flags;
 851
 852         atomic_set(&tx->enabled, 0);
 853
 854         /* kill all submitted tx-urbs */
 855         usb_kill_anchored_urbs(&tx->submitted);
 856
 857         spin_lock_irqsave(&tx->lock, flags);
 858         WARN_ON(!skb_queue_empty(&tx->submitted_skbs));
 859         WARN_ON(tx->submitted_urbs != 0);
 860         tx->submitted_urbs = 0;
 861         spin_unlock_irqrestore(&tx->lock, flags);
 862
 863         /* The stopped state is ignored, relying on ieee80211_wake_queues()
 864          * in a potentionally following zd_usb_enable_tx().
 865          */
 866 }
 867
 868 /**
 869  * zd_usb_enable_tx - enables transmission
 870  * @usb: a &struct zd_usb pointer
 871  *
 872  * This function enables transmission and prepares the &zd_usb_tx data
 873  * structure.
 874  */
 875 void zd_usb_enable_tx(struct zd_usb *usb)
 876 {
 877         unsigned long flags;
 878         struct zd_usb_tx *tx = &usb->tx;
 879
 880         spin_lock_irqsave(&tx->lock, flags);
 881         atomic_set(&tx->enabled, 1);
 882         tx->submitted_urbs = 0;
 883         ieee80211_wake_queues(zd_usb_to_hw(usb));
 884         tx->stopped = 0;
 885         spin_unlock_irqrestore(&tx->lock, flags);
 886 }
 887
 888 static void tx_dec_submitted_urbs(struct zd_usb *usb)
 889 {
 890         struct zd_usb_tx *tx = &usb->tx;
 891         unsigned long flags;
 892
 893         spin_lock_irqsave(&tx->lock, flags);
 894         --tx->submitted_urbs;
 895         if (tx->stopped && tx->submitted_urbs <= ZD_USB_TX_LOW) {
 896                 ieee80211_wake_queues(zd_usb_to_hw(usb));
 897                 tx->stopped = 0;
 898         }
 899         spin_unlock_irqrestore(&tx->lock, flags);
 900 }
 901
 902 static void tx_inc_submitted_urbs(struct zd_usb *usb)
 903 {
 904         struct zd_usb_tx *tx = &usb->tx;
 905         unsigned long flags;
 906
 907         spin_lock_irqsave(&tx->lock, flags);
 908         ++tx->submitted_urbs;
 909         if (!tx->stopped && tx->submitted_urbs > ZD_USB_TX_HIGH) {
 910                 ieee80211_stop_queues(zd_usb_to_hw(usb));
 911                 tx->stopped = 1;
 912         }
 913         spin_unlock_irqrestore(&tx->lock, flags);
 914 }
 915
 916 /**
 917  * tx_urb_complete - completes the execution of an URB
 918  * @urb: a URB
 919  *
 920  * This function is called if the URB has been transferred to a device or an
 921  * error has happened.
 922  */
 923 static void tx_urb_complete(struct urb *urb)
 924 {
 925         int r;
 926         struct sk_buff *skb;
 927         struct ieee80211_tx_info *info;
 928         struct zd_usb *usb;
 929         struct zd_usb_tx *tx;
 930
 931         skb = (struct sk_buff *)urb->context;
 932         info = IEEE80211_SKB_CB(skb);
 933         /*
 934          * grab 'usb' pointer before handing off the skb (since
 935          * it might be freed by zd_mac_tx_to_dev or mac80211)
 936          */
 937         usb = &zd_hw_mac(info->rate_driver_data[0])->chip.usb;
 938         tx = &usb->tx;
 939
 940         switch (urb->status) {
 941         case 0:
 942                 break;
 943         case -ESHUTDOWN:
 944         case -EINVAL:
 945         case -ENODEV:
 946         case -ENOENT:
 947         case -ECONNRESET:
 948         case -EPIPE:
 949                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 950                 break;
 951         default:
 952                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 953                 goto resubmit;
 954         }
 955 free_urb:
 956         skb_unlink(skb, &usb->tx.submitted_skbs);
 957         zd_mac_tx_to_dev(skb, urb->status);
 958         usb_free_urb(urb);
 959         tx_dec_submitted_urbs(usb);
 960         return;
 961 resubmit:
 962         usb_anchor_urb(urb, &tx->submitted);
 963         r = usb_submit_urb(urb, GFP_ATOMIC);
 964         if (r) {
 965                 usb_unanchor_urb(urb);
 966                 dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
 967                 goto free_urb;
 968         }
 969 }
 970
 971 /**
 972  * zd_usb_tx: initiates transfer of a frame of the device
 973  *
 974  * @usb: the zd1211rw-private USB structure
 975  * @skb: a &struct sk_buff pointer
 976  *
 977  * This function tranmits a frame to the device. It doesn't wait for
 978  * completion. The frame must contain the control set and have all the
 979  * control set information available.
 980  *
 981  * The function returns 0 if the transfer has been successfully initiated.
 982  */
 983 int zd_usb_tx(struct zd_usb *usb, struct sk_buff *skb)
 984 {
 985         int r;
 986         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 987         struct usb_device *udev = zd_usb_to_usbdev(usb);
 988         struct urb *urb;
 989         struct zd_usb_tx *tx = &usb->tx;
 990
 991         if (!atomic_read(&tx->enabled)) {
 992                 r = -ENOENT;
 993                 goto out;
 994         }
 995
 996         urb = usb_alloc_urb(0, GFP_ATOMIC);
 997         if (!urb) {
 998                 r = -ENOMEM;
 999                 goto out;
1000         }
1001
1002         usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
1003                           skb->data, skb->len, tx_urb_complete, skb);
1004
1005         info->rate_driver_data[1] = (void *)jiffies;
1006         skb_queue_tail(&tx->submitted_skbs, skb);
1007         usb_anchor_urb(urb, &tx->submitted);
1008
1009         r = usb_submit_urb(urb, GFP_ATOMIC);
1010         if (r) {
1011                 dev_dbg_f(zd_usb_dev(usb), "error submit urb %p %d\n", urb, r);
1012                 usb_unanchor_urb(urb);
1013                 skb_unlink(skb, &tx->submitted_skbs);
1014                 goto error;
1015         }
1016         tx_inc_submitted_urbs(usb);
1017         return 0;
1018 error:
1019         usb_free_urb(urb);
1020 out:
1021         return r;
1022 }
1023
1024 static bool zd_tx_timeout(struct zd_usb *usb)
1025 {
1026         struct zd_usb_tx *tx = &usb->tx;
1027         struct sk_buff_head *q = &tx->submitted_skbs;
1028         struct sk_buff *skb, *skbnext;
1029         struct ieee80211_tx_info *info;
1030         unsigned long flags, trans_start;
1031         bool have_timedout = false;
1032
1033         spin_lock_irqsave(&q->lock, flags);
1034         skb_queue_walk_safe(q, skb, skbnext) {
1035                 info = IEEE80211_SKB_CB(skb);
1036                 trans_start = (unsigned long)info->rate_driver_data[1];
1037
1038                 if (time_is_before_jiffies(trans_start + ZD_TX_TIMEOUT)) {
1039                         have_timedout = true;
1040                         break;
1041                 }
1042         }
1043         spin_unlock_irqrestore(&q->lock, flags);
1044
1045         return have_timedout;
1046 }
1047
1048 static void zd_tx_watchdog_handler(struct work_struct *work)
1049 {
1050         struct zd_usb *usb =
1051                 container_of(work, struct zd_usb, tx.watchdog_work.work);
1052         struct zd_usb_tx *tx = &usb->tx;
1053
1054         if (!atomic_read(&tx->enabled) || !tx->watchdog_enabled)
1055                 goto out;
1056         if (!zd_tx_timeout(usb))
1057                 goto out;
1058
1059         /* TX halted, try reset */
1060         dev_warn(zd_usb_dev(usb), "TX-stall detected, reseting device...");
1061
1062         usb_queue_reset_device(usb->intf);
1063
1064         /* reset will stop this worker, don't rearm */
1065         return;
1066 out:
1067         queue_delayed_work(zd_workqueue, &tx->watchdog_work,
1068                            ZD_TX_WATCHDOG_INTERVAL);
1069 }
1070
1071 void zd_tx_watchdog_enable(struct zd_usb *usb)
1072 {
1073         struct zd_usb_tx *tx = &usb->tx;
1074
1075         if (!tx->watchdog_enabled) {
1076                 dev_dbg_f(zd_usb_dev(usb), "\n");
1077                 queue_delayed_work(zd_workqueue, &tx->watchdog_work,
1078                                    ZD_TX_WATCHDOG_INTERVAL);
1079                 tx->watchdog_enabled = 1;
1080         }
1081 }
1082
1083 void zd_tx_watchdog_disable(struct zd_usb *usb)
1084 {
1085         struct zd_usb_tx *tx = &usb->tx;
1086
1087         if (tx->watchdog_enabled) {
1088                 dev_dbg_f(zd_usb_dev(usb), "\n");
1089                 tx->watchdog_enabled = 0;
1090                 cancel_delayed_work_sync(&tx->watchdog_work);
1091         }
1092 }
1093
1094 static void zd_rx_idle_timer_handler(struct work_struct *work)
1095 {
1096         struct zd_usb *usb =
1097                 container_of(work, struct zd_usb, rx.idle_work.work);
1098         struct zd_mac *mac = zd_usb_to_mac(usb);
1099
1100         if (!test_bit(ZD_DEVICE_RUNNING, &mac->flags))
1101                 return;
1102
1103         dev_dbg_f(zd_usb_dev(usb), "\n");
1104
1105         /* 30 seconds since last rx, reset rx */
1106         zd_usb_reset_rx(usb);
1107 }
1108
1109 void zd_usb_reset_rx_idle_timer(struct zd_usb *usb)
1110 {
1111         struct zd_usb_rx *rx = &usb->rx;
1112
1113         cancel_delayed_work(&rx->idle_work);
1114         queue_delayed_work(zd_workqueue, &rx->idle_work, ZD_RX_IDLE_INTERVAL);
1115 }
1116
1117 static inline void init_usb_interrupt(struct zd_usb *usb)
1118 {
1119         struct zd_usb_interrupt *intr = &usb->intr;
1120
1121         spin_lock_init(&intr->lock);
1122         intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
1123         init_completion(&intr->read_regs.completion);
1124         intr->read_regs.cr_int_addr = cpu_to_le16((u16)CR_INTERRUPT);
1125 }
1126
1127 static inline void init_usb_rx(struct zd_usb *usb)
1128 {
1129         struct zd_usb_rx *rx = &usb->rx;
1130         spin_lock_init(&rx->lock);
1131         mutex_init(&rx->setup_mutex);
1132         if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
1133                 rx->usb_packet_size = 512;
1134         } else {
1135                 rx->usb_packet_size = 64;
1136         }
1137         ZD_ASSERT(rx->fragment_length == 0);
1138         INIT_DELAYED_WORK(&rx->idle_work, zd_rx_idle_timer_handler);
1139 }
1140
1141 static inline void init_usb_tx(struct zd_usb *usb)
1142 {
1143         struct zd_usb_tx *tx = &usb->tx;
1144         spin_lock_init(&tx->lock);
1145         atomic_set(&tx->enabled, 0);
1146         tx->stopped = 0;
1147         skb_queue_head_init(&tx->submitted_skbs);
1148         init_usb_anchor(&tx->submitted);
1149         tx->submitted_urbs = 0;
1150         tx->watchdog_enabled = 0;
1151         INIT_DELAYED_WORK(&tx->watchdog_work, zd_tx_watchdog_handler);
1152 }
1153
1154 void zd_usb_init(struct zd_usb *usb, struct ieee80211_hw *hw,
1155                  struct usb_interface *intf)
1156 {
1157         memset(usb, 0, sizeof(*usb));
1158         usb->intf = usb_get_intf(intf);
1159         usb_set_intfdata(usb->intf, hw);
1160         init_usb_anchor(&usb->submitted_cmds);
1161         init_usb_interrupt(usb);
1162         init_usb_tx(usb);
1163         init_usb_rx(usb);
1164 }
1165
1166 void zd_usb_clear(struct zd_usb *usb)
1167 {
1168         usb_set_intfdata(usb->intf, NULL);
1169         usb_put_intf(usb->intf);
1170         ZD_MEMCLEAR(usb, sizeof(*usb));
1171         /* FIXME: usb_interrupt, usb_tx, usb_rx? */
1172 }
1173
1174 static const char *speed(enum usb_device_speed speed)
1175 {
1176         switch (speed) {
1177         case USB_SPEED_LOW:
1178                 return "low";
1179         case USB_SPEED_FULL:
1180                 return "full";
1181         case USB_SPEED_HIGH:
1182                 return "high";
1183         default:
1184                 return "unknown speed";
1185         }
1186 }
1187
1188 static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
1189 {
1190         return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
1191                 le16_to_cpu(udev->descriptor.idVendor),
1192                 le16_to_cpu(udev->descriptor.idProduct),
1193                 get_bcdDevice(udev),
1194                 speed(udev->speed));
1195 }
1196
1197 int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
1198 {
1199         struct usb_device *udev = interface_to_usbdev(usb->intf);
1200         return scnprint_id(udev, buffer, size);
1201 }
1202
1203 #ifdef DEBUG
1204 static void print_id(struct usb_device *udev)
1205 {
1206         char buffer[40];
1207
1208         scnprint_id(udev, buffer, sizeof(buffer));
1209         buffer[sizeof(buffer)-1] = 0;
1210         dev_dbg_f(&udev->dev, "%s\n", buffer);
1211 }
1212 #else
1213 #define print_id(udev) do { } while (0)
1214 #endif
1215
1216 static int eject_installer(struct usb_interface *intf)
1217 {
1218         struct usb_device *udev = interface_to_usbdev(intf);
1219         struct usb_host_interface *iface_desc = &intf->altsetting[0];
1220         struct usb_endpoint_descriptor *endpoint;
1221         unsigned char *cmd;
1222         u8 bulk_out_ep;
1223         int r;
1224
1225         /* Find bulk out endpoint */
1226         for (r = 1; r >= 0; r--) {
1227                 endpoint = &iface_desc->endpoint[r].desc;
1228                 if (usb_endpoint_dir_out(endpoint) &&
1229                     usb_endpoint_xfer_bulk(endpoint)) {
1230                         bulk_out_ep = endpoint->bEndpointAddress;
1231                         break;
1232                 }
1233         }
1234         if (r == -1) {
1235                 dev_err(&udev->dev,
1236                         "zd1211rw: Could not find bulk out endpoint\n");
1237                 return -ENODEV;
1238         }
1239
1240         cmd = kzalloc(31, GFP_KERNEL);
1241         if (cmd == NULL)
1242                 return -ENODEV;
1243
1244         /* USB bulk command block */
1245         cmd[0] = 0x55;  /* bulk command signature */
1246         cmd[1] = 0x53;  /* bulk command signature */
1247         cmd[2] = 0x42;  /* bulk command signature */
1248         cmd[3] = 0x43;  /* bulk command signature */
1249         cmd[14] = 6;    /* command length */
1250
1251         cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
1252         cmd[19] = 0x2;  /* eject disc */
1253
1254         dev_info(&udev->dev, "Ejecting virtual installer media...\n");
1255         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
1256                 cmd, 31, NULL, 2000);
1257         kfree(cmd);
1258         if (r)
1259                 return r;
1260
1261         /* At this point, the device disconnects and reconnects with the real
1262          * ID numbers. */
1263
1264         usb_set_intfdata(intf, NULL);
1265         return 0;
1266 }
1267
1268 int zd_usb_init_hw(struct zd_usb *usb)
1269 {
1270         int r;
1271         struct zd_mac *mac = zd_usb_to_mac(usb);
1272
1273         dev_dbg_f(zd_usb_dev(usb), "\n");
1274
1275         r = upload_firmware(usb);
1276         if (r) {
1277                 dev_err(zd_usb_dev(usb),
1278                        "couldn't load firmware. Error number %d\n", r);
1279                 return r;
1280         }
1281
1282         r = usb_reset_configuration(zd_usb_to_usbdev(usb));
1283         if (r) {
1284                 dev_dbg_f(zd_usb_dev(usb),
1285                         "couldn't reset configuration. Error number %d\n", r);
1286                 return r;
1287         }
1288
1289         r = zd_mac_init_hw(mac->hw);
1290         if (r) {
1291                 dev_dbg_f(zd_usb_dev(usb),
1292                          "couldn't initialize mac. Error number %d\n", r);
1293                 return r;
1294         }
1295
1296         usb->initialized = 1;
1297         return 0;
1298 }
1299
1300 static int probe(struct usb_interface *intf, const struct usb_device_id *id)
1301 {
1302         int r;
1303         struct usb_device *udev = interface_to_usbdev(intf);
1304         struct zd_usb *usb;
1305         struct ieee80211_hw *hw = NULL;
1306
1307         print_id(udev);
1308
1309         if (id->driver_info & DEVICE_INSTALLER)
1310                 return eject_installer(intf);
1311
1312         switch (udev->speed) {
1313         case USB_SPEED_LOW:
1314         case USB_SPEED_FULL:
1315         case USB_SPEED_HIGH:
1316                 break;
1317         default:
1318                 dev_dbg_f(&intf->dev, "Unknown USB speed\n");
1319                 r = -ENODEV;
1320                 goto error;
1321         }
1322
1323         r = usb_reset_device(udev);
1324         if (r) {
1325                 dev_err(&intf->dev,
1326                         "couldn't reset usb device. Error number %d\n", r);
1327                 goto error;
1328         }
1329
1330         hw = zd_mac_alloc_hw(intf);
1331         if (hw == NULL) {
1332                 r = -ENOMEM;
1333                 goto error;
1334         }
1335
1336         usb = &zd_hw_mac(hw)->chip.usb;
1337         usb->is_zd1211b = (id->driver_info == DEVICE_ZD1211B) != 0;
1338
1339         r = zd_mac_preinit_hw(hw);
1340         if (r) {
1341                 dev_dbg_f(&intf->dev,
1342                          "couldn't initialize mac. Error number %d\n", r);
1343                 goto error;
1344         }
1345
1346         r = ieee80211_register_hw(hw);
1347         if (r) {
1348                 dev_dbg_f(&intf->dev,
1349                          "couldn't register device. Error number %d\n", r);
1350                 goto error;
1351         }
1352
1353         dev_dbg_f(&intf->dev, "successful\n");
1354         dev_info(&intf->dev, "%s\n", wiphy_name(hw->wiphy));
1355         return 0;
1356 error:
1357         usb_reset_device(interface_to_usbdev(intf));
1358         if (hw) {
1359                 zd_mac_clear(zd_hw_mac(hw));
1360                 ieee80211_free_hw(hw);
1361         }
1362         return r;
1363 }
1364
1365 static void disconnect(struct usb_interface *intf)
1366 {
1367         struct ieee80211_hw *hw = zd_intf_to_hw(intf);
1368         struct zd_mac *mac;
1369         struct zd_usb *usb;
1370
1371         /* Either something really bad happened, or we're just dealing with
1372          * a DEVICE_INSTALLER. */
1373         if (hw == NULL)
1374                 return;
1375
1376         mac = zd_hw_mac(hw);
1377         usb = &mac->chip.usb;
1378
1379         dev_dbg_f(zd_usb_dev(usb), "\n");
1380
1381         ieee80211_unregister_hw(hw);
1382
1383         /* Just in case something has gone wrong! */
1384         zd_usb_disable_tx(usb);
1385         zd_usb_disable_rx(usb);
1386         zd_usb_disable_int(usb);
1387
1388         /* If the disconnect has been caused by a removal of the
1389          * driver module, the reset allows reloading of the driver. If the
1390          * reset will not be executed here, the upload of the firmware in the
1391          * probe function caused by the reloading of the driver will fail.
1392          */
1393         usb_reset_device(interface_to_usbdev(intf));
1394
1395         zd_mac_clear(mac);
1396         ieee80211_free_hw(hw);
1397         dev_dbg(&intf->dev, "disconnected\n");
1398 }
1399
1400 static void zd_usb_resume(struct zd_usb *usb)
1401 {
1402         struct zd_mac *mac = zd_usb_to_mac(usb);
1403         int r;
1404
1405         dev_dbg_f(zd_usb_dev(usb), "\n");
1406
1407         r = zd_op_start(zd_usb_to_hw(usb));
1408         if (r < 0) {
1409                 dev_warn(zd_usb_dev(usb), "Device resume failed "
1410                          "with error code %d. Retrying...\n", r);
1411                 if (usb->was_running)
1412                         set_bit(ZD_DEVICE_RUNNING, &mac->flags);
1413                 usb_queue_reset_device(usb->intf);
1414                 return;
1415         }
1416
1417         if (mac->type != NL80211_IFTYPE_UNSPECIFIED) {
1418                 r = zd_restore_settings(mac);
1419                 if (r < 0) {
1420                         dev_dbg(zd_usb_dev(usb),
1421                                 "failed to restore settings, %d\n", r);
1422                         return;
1423                 }
1424         }
1425 }
1426
1427 static void zd_usb_stop(struct zd_usb *usb)
1428 {
1429         dev_dbg_f(zd_usb_dev(usb), "\n");
1430
1431         zd_op_stop(zd_usb_to_hw(usb));
1432
1433         zd_usb_disable_tx(usb);
1434         zd_usb_disable_rx(usb);
1435         zd_usb_disable_int(usb);
1436
1437         usb->initialized = 0;
1438 }
1439
1440 static int pre_reset(struct usb_interface *intf)
1441 {
1442         struct ieee80211_hw *hw = usb_get_intfdata(intf);
1443         struct zd_mac *mac;
1444         struct zd_usb *usb;
1445
1446         if (!hw || intf->condition != USB_INTERFACE_BOUND)
1447                 return 0;
1448
1449         mac = zd_hw_mac(hw);
1450         usb = &mac->chip.usb;
1451
1452         usb->was_running = test_bit(ZD_DEVICE_RUNNING, &mac->flags);
1453
1454         zd_usb_stop(usb);
1455
1456         mutex_lock(&mac->chip.mutex);
1457         return 0;
1458 }
1459
1460 static int post_reset(struct usb_interface *intf)
1461 {
1462         struct ieee80211_hw *hw = usb_get_intfdata(intf);
1463         struct zd_mac *mac;
1464         struct zd_usb *usb;
1465
1466         if (!hw || intf->condition != USB_INTERFACE_BOUND)
1467                 return 0;
1468
1469         mac = zd_hw_mac(hw);
1470         usb = &mac->chip.usb;
1471
1472         mutex_unlock(&mac->chip.mutex);
1473
1474         if (usb->was_running)
1475                 zd_usb_resume(usb);
1476         return 0;
1477 }
1478
1479 static struct usb_driver driver = {
1480         .name           = KBUILD_MODNAME,
1481         .id_table       = usb_ids,
1482         .probe          = probe,
1483         .disconnect     = disconnect,
1484         .pre_reset      = pre_reset,
1485         .post_reset     = post_reset,
1486 };
1487
1488 struct workqueue_struct *zd_workqueue;
1489
1490 static int __init usb_init(void)
1491 {
1492         int r;
1493
1494         pr_debug("%s usb_init()\n", driver.name);
1495
1496         zd_workqueue = create_singlethread_workqueue(driver.name);
1497         if (zd_workqueue == NULL) {
1498                 printk(KERN_ERR "%s couldn't create workqueue\n", driver.name);
1499                 return -ENOMEM;
1500         }
1501
1502         r = usb_register(&driver);
1503         if (r) {
1504                 destroy_workqueue(zd_workqueue);
1505                 printk(KERN_ERR "%s usb_register() failed. Error number %d\n",
1506                        driver.name, r);
1507                 return r;
1508         }
1509
1510         pr_debug("%s initialized\n", driver.name);
1511         return 0;
1512 }
1513
1514 static void __exit usb_exit(void)
1515 {
1516         pr_debug("%s usb_exit()\n", driver.name);
1517         usb_deregister(&driver);
1518         destroy_workqueue(zd_workqueue);
1519 }
1520
1521 module_init(usb_init);
1522 module_exit(usb_exit);
1523
1524 static int usb_int_regs_length(unsigned int count)
1525 {
1526         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1527 }
1528
1529 static void prepare_read_regs_int(struct zd_usb *usb)
1530 {
1531         struct zd_usb_interrupt *intr = &usb->intr;
1532
1533         spin_lock_irq(&intr->lock);
1534         intr->read_regs_enabled = 1;
1535         INIT_COMPLETION(intr->read_regs.completion);
1536         spin_unlock_irq(&intr->lock);
1537 }
1538
1539 static void disable_read_regs_int(struct zd_usb *usb)
1540 {
1541         struct zd_usb_interrupt *intr = &usb->intr;
1542
1543         spin_lock_irq(&intr->lock);
1544         intr->read_regs_enabled = 0;
1545         spin_unlock_irq(&intr->lock);
1546 }
1547
1548 static int get_results(struct zd_usb *usb, u16 *values,
1549                        struct usb_req_read_regs *req, unsigned int count)
1550 {
1551         int r;
1552         int i;
1553         struct zd_usb_interrupt *intr = &usb->intr;
1554         struct read_regs_int *rr = &intr->read_regs;
1555         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1556
1557         spin_lock_irq(&intr->lock);
1558
1559         r = -EIO;
1560         /* The created block size seems to be larger than expected.
1561          * However results appear to be correct.
1562          */
1563         if (rr->length < usb_int_regs_length(count)) {
1564                 dev_dbg_f(zd_usb_dev(usb),
1565                          "error: actual length %d less than expected %d\n",
1566                          rr->length, usb_int_regs_length(count));
1567                 goto error_unlock;
1568         }
1569         if (rr->length > sizeof(rr->buffer)) {
1570                 dev_dbg_f(zd_usb_dev(usb),
1571                          "error: actual length %d exceeds buffer size %zu\n",
1572                          rr->length, sizeof(rr->buffer));
1573                 goto error_unlock;
1574         }
1575
1576         for (i = 0; i < count; i++) {
1577                 struct reg_data *rd = &regs->regs[i];
1578                 if (rd->addr != req->addr[i]) {
1579                         dev_dbg_f(zd_usb_dev(usb),
1580                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1581                                  le16_to_cpu(rd->addr),
1582                                  le16_to_cpu(req->addr[i]));
1583                         goto error_unlock;
1584                 }
1585                 values[i] = le16_to_cpu(rd->value);
1586         }
1587
1588         r = 0;
1589 error_unlock:
1590         spin_unlock_irq(&intr->lock);
1591         return r;
1592 }
1593
1594 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1595                      const zd_addr_t *addresses, unsigned int count)
1596 {
1597         int r;
1598         int i, req_len, actual_req_len;
1599         struct usb_device *udev;
1600         struct usb_req_read_regs *req = NULL;
1601         unsigned long timeout;
1602
1603         if (count < 1) {
1604                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1605                 return -EINVAL;
1606         }
1607         if (count > USB_MAX_IOREAD16_COUNT) {
1608                 dev_dbg_f(zd_usb_dev(usb),
1609                          "error: count %u exceeds possible max %u\n",
1610                          count, USB_MAX_IOREAD16_COUNT);
1611                 return -EINVAL;
1612         }
1613         if (in_atomic()) {
1614                 dev_dbg_f(zd_usb_dev(usb),
1615                          "error: io in atomic context not supported\n");
1616                 return -EWOULDBLOCK;
1617         }
1618         if (!usb_int_enabled(usb)) {
1619                 dev_dbg_f(zd_usb_dev(usb),
1620                           "error: usb interrupt not enabled\n");
1621                 return -EWOULDBLOCK;
1622         }
1623
1624         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1625         BUILD_BUG_ON(sizeof(struct usb_req_read_regs) + USB_MAX_IOREAD16_COUNT *
1626                      sizeof(__le16) > sizeof(usb->req_buf));
1627         BUG_ON(sizeof(struct usb_req_read_regs) + count * sizeof(__le16) >
1628                sizeof(usb->req_buf));
1629
1630         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1631         req = (void *)usb->req_buf;
1632
1633         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1634         for (i = 0; i < count; i++)
1635                 req->addr[i] = cpu_to_le16((u16)addresses[i]);
1636
1637         udev = zd_usb_to_usbdev(usb);
1638         prepare_read_regs_int(usb);
1639         r = usb_interrupt_msg(udev, usb_sndintpipe(udev, EP_REGS_OUT),
1640                               req, req_len, &actual_req_len, 50 /* ms */);
1641         if (r) {
1642                 dev_dbg_f(zd_usb_dev(usb),
1643                         "error in usb_interrupt_msg(). Error number %d\n", r);
1644                 goto error;
1645         }
1646         if (req_len != actual_req_len) {
1647                 dev_dbg_f(zd_usb_dev(usb), "error in usb_interrupt_msg()\n"
1648                         " req_len %d != actual_req_len %d\n",
1649                         req_len, actual_req_len);
1650                 r = -EIO;
1651                 goto error;
1652         }
1653
1654         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1655                                               msecs_to_jiffies(50));
1656         if (!timeout) {
1657                 disable_read_regs_int(usb);
1658                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1659                 r = -ETIMEDOUT;
1660                 goto error;
1661         }
1662
1663         r = get_results(usb, values, req, count);
1664 error:
1665         return r;
1666 }
1667
1668 static void iowrite16v_urb_complete(struct urb *urb)
1669 {
1670         struct zd_usb *usb = urb->context;
1671
1672         if (urb->status && !usb->cmd_error)
1673                 usb->cmd_error = urb->status;
1674
1675         if (!usb->cmd_error &&
1676                         urb->actual_length != urb->transfer_buffer_length)
1677                 usb->cmd_error = -EIO;
1678 }
1679
1680 static int zd_submit_waiting_urb(struct zd_usb *usb, bool last)
1681 {
1682         int r = 0;
1683         struct urb *urb = usb->urb_async_waiting;
1684
1685         if (!urb)
1686                 return 0;
1687
1688         usb->urb_async_waiting = NULL;
1689
1690         if (!last)
1691                 urb->transfer_flags |= URB_NO_INTERRUPT;
1692
1693         usb_anchor_urb(urb, &usb->submitted_cmds);
1694         r = usb_submit_urb(urb, GFP_KERNEL);
1695         if (r) {
1696                 usb_unanchor_urb(urb);
1697                 dev_dbg_f(zd_usb_dev(usb),
1698                         "error in usb_submit_urb(). Error number %d\n", r);
1699                 goto error;
1700         }
1701
1702         /* fall-through with r == 0 */
1703 error:
1704         usb_free_urb(urb);
1705         return r;
1706 }
1707
1708 void zd_usb_iowrite16v_async_start(struct zd_usb *usb)
1709 {
1710         ZD_ASSERT(usb_anchor_empty(&usb->submitted_cmds));
1711         ZD_ASSERT(usb->urb_async_waiting == NULL);
1712         ZD_ASSERT(!usb->in_async);
1713
1714         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1715
1716         usb->in_async = 1;
1717         usb->cmd_error = 0;
1718         usb->urb_async_waiting = NULL;
1719 }
1720
1721 int zd_usb_iowrite16v_async_end(struct zd_usb *usb, unsigned int timeout)
1722 {
1723         int r;
1724
1725         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1726         ZD_ASSERT(usb->in_async);
1727
1728         /* Submit last iowrite16v URB */
1729         r = zd_submit_waiting_urb(usb, true);
1730         if (r) {
1731                 dev_dbg_f(zd_usb_dev(usb),
1732                         "error in zd_submit_waiting_usb(). "
1733                         "Error number %d\n", r);
1734
1735                 usb_kill_anchored_urbs(&usb->submitted_cmds);
1736                 goto error;
1737         }
1738
1739         if (timeout)
1740                 timeout = usb_wait_anchor_empty_timeout(&usb->submitted_cmds,
1741                                                         timeout);
1742         if (!timeout) {
1743                 usb_kill_anchored_urbs(&usb->submitted_cmds);
1744                 if (usb->cmd_error == -ENOENT) {
1745                         dev_dbg_f(zd_usb_dev(usb), "timed out");
1746                         r = -ETIMEDOUT;
1747                         goto error;
1748                 }
1749         }
1750
1751         r = usb->cmd_error;
1752 error:
1753         usb->in_async = 0;
1754         return r;
1755 }
1756
1757 int zd_usb_iowrite16v_async(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1758                             unsigned int count)
1759 {
1760         int r;
1761         struct usb_device *udev;
1762         struct usb_req_write_regs *req = NULL;
1763         int i, req_len;
1764         struct urb *urb;
1765         struct usb_host_endpoint *ep;
1766
1767         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1768         ZD_ASSERT(usb->in_async);
1769
1770         if (count == 0)
1771                 return 0;
1772         if (count > USB_MAX_IOWRITE16_COUNT) {
1773                 dev_dbg_f(zd_usb_dev(usb),
1774                         "error: count %u exceeds possible max %u\n",
1775                         count, USB_MAX_IOWRITE16_COUNT);
1776                 return -EINVAL;
1777         }
1778         if (in_atomic()) {
1779                 dev_dbg_f(zd_usb_dev(usb),
1780                         "error: io in atomic context not supported\n");
1781                 return -EWOULDBLOCK;
1782         }
1783
1784         udev = zd_usb_to_usbdev(usb);
1785
1786         ep = usb_pipe_endpoint(udev, usb_sndintpipe(udev, EP_REGS_OUT));
1787         if (!ep)
1788                 return -ENOENT;
1789
1790         urb = usb_alloc_urb(0, GFP_KERNEL);
1791         if (!urb)
1792                 return -ENOMEM;
1793
1794         req_len = sizeof(struct usb_req_write_regs) +
1795                   count * sizeof(struct reg_data);
1796         req = kmalloc(req_len, GFP_KERNEL);
1797         if (!req) {
1798                 r = -ENOMEM;
1799                 goto error;
1800         }
1801
1802         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1803         for (i = 0; i < count; i++) {
1804                 struct reg_data *rw  = &req->reg_writes[i];
1805                 rw->addr = cpu_to_le16((u16)ioreqs[i].addr);
1806                 rw->value = cpu_to_le16(ioreqs[i].value);
1807         }
1808
1809         usb_fill_int_urb(urb, udev, usb_sndintpipe(udev, EP_REGS_OUT),
1810                          req, req_len, iowrite16v_urb_complete, usb,
1811                          ep->desc.bInterval);
1812         urb->transfer_flags |= URB_FREE_BUFFER;
1813
1814         /* Submit previous URB */
1815         r = zd_submit_waiting_urb(usb, false);
1816         if (r) {
1817                 dev_dbg_f(zd_usb_dev(usb),
1818                         "error in zd_submit_waiting_usb(). "
1819                         "Error number %d\n", r);
1820                 goto error;
1821         }
1822
1823         /* Delay submit so that URB_NO_INTERRUPT flag can be set for all URBs
1824          * of currect batch except for very last.
1825          */
1826         usb->urb_async_waiting = urb;
1827         return 0;
1828 error:
1829         usb_free_urb(urb);
1830         return r;
1831 }
1832
1833 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1834                         unsigned int count)
1835 {
1836         int r;
1837
1838         zd_usb_iowrite16v_async_start(usb);
1839         r = zd_usb_iowrite16v_async(usb, ioreqs, count);
1840         if (r) {
1841                 zd_usb_iowrite16v_async_end(usb, 0);
1842                 return r;
1843         }
1844         return zd_usb_iowrite16v_async_end(usb, 50 /* ms */);
1845 }
1846
1847 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1848 {
1849         int r;
1850         struct usb_device *udev;
1851         struct usb_req_rfwrite *req = NULL;
1852         int i, req_len, actual_req_len;
1853         u16 bit_value_template;
1854
1855         if (in_atomic()) {
1856                 dev_dbg_f(zd_usb_dev(usb),
1857                         "error: io in atomic context not supported\n");
1858                 return -EWOULDBLOCK;
1859         }
1860         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1861                 dev_dbg_f(zd_usb_dev(usb),
1862                         "error: bits %d are smaller than"
1863                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1864                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1865                 return -EINVAL;
1866         }
1867         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1868                 dev_dbg_f(zd_usb_dev(usb),
1869                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1870                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1871                 return -EINVAL;
1872         }
1873 #ifdef DEBUG
1874         if (value & (~0UL << bits)) {
1875                 dev_dbg_f(zd_usb_dev(usb),
1876                         "error: value %#09x has bits >= %d set\n",
1877                         value, bits);
1878                 return -EINVAL;
1879         }
1880 #endif /* DEBUG */
1881
1882         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1883
1884         r = zd_usb_ioread16(usb, &bit_value_template, CR203);
1885         if (r) {
1886                 dev_dbg_f(zd_usb_dev(usb),
1887                         "error %d: Couldn't read CR203\n", r);
1888                 return r;
1889         }
1890         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1891
1892         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1893         BUILD_BUG_ON(sizeof(struct usb_req_rfwrite) +
1894                      USB_MAX_RFWRITE_BIT_COUNT * sizeof(__le16) >
1895                      sizeof(usb->req_buf));
1896         BUG_ON(sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16) >
1897                sizeof(usb->req_buf));
1898
1899         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1900         req = (void *)usb->req_buf;
1901
1902         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1903         /* 1: 3683a, but not used in ZYDAS driver */
1904         req->value = cpu_to_le16(2);
1905         req->bits = cpu_to_le16(bits);
1906
1907         for (i = 0; i < bits; i++) {
1908                 u16 bv = bit_value_template;
1909                 if (value & (1 << (bits-1-i)))
1910                         bv |= RF_DATA;
1911                 req->bit_values[i] = cpu_to_le16(bv);
1912         }
1913
1914         udev = zd_usb_to_usbdev(usb);
1915         r = usb_interrupt_msg(udev, usb_sndintpipe(udev, EP_REGS_OUT),
1916                               req, req_len, &actual_req_len, 50 /* ms */);
1917         if (r) {
1918                 dev_dbg_f(zd_usb_dev(usb),
1919                         "error in usb_interrupt_msg(). Error number %d\n", r);
1920                 goto out;
1921         }
1922         if (req_len != actual_req_len) {
1923                 dev_dbg_f(zd_usb_dev(usb), "error in usb_interrupt_msg()"
1924                         " req_len %d != actual_req_len %d\n",
1925                         req_len, actual_req_len);
1926                 r = -EIO;
1927                 goto out;
1928         }
1929
1930         /* FALL-THROUGH with r == 0 */
1931 out:
1932         return r;
1933 }