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(0x1740, 0x2000), .driver_info = DEVICE_ZD1211 },
  64         { USB_DEVICE(0x6891, 0xa727), .driver_info = DEVICE_ZD1211 },
  65         /* ZD1211B */
  66         { USB_DEVICE(0x0053, 0x5301), .driver_info = DEVICE_ZD1211B },
  67         { USB_DEVICE(0x0409, 0x0248), .driver_info = DEVICE_ZD1211B },
  68         { USB_DEVICE(0x0411, 0x00da), .driver_info = DEVICE_ZD1211B },
  69         { USB_DEVICE(0x0471, 0x1236), .driver_info = DEVICE_ZD1211B },
  70         { USB_DEVICE(0x0471, 0x1237), .driver_info = DEVICE_ZD1211B },
  71         { USB_DEVICE(0x050d, 0x705c), .driver_info = DEVICE_ZD1211B },
  72         { USB_DEVICE(0x054c, 0x0257), .driver_info = DEVICE_ZD1211B },
  73         { USB_DEVICE(0x0586, 0x340a), .driver_info = DEVICE_ZD1211B },
  74         { USB_DEVICE(0x0586, 0x340f), .driver_info = DEVICE_ZD1211B },
  75         { USB_DEVICE(0x0586, 0x3410), .driver_info = DEVICE_ZD1211B },
  76         { USB_DEVICE(0x0586, 0x3412), .driver_info = DEVICE_ZD1211B },
  77         { USB_DEVICE(0x0586, 0x3413), .driver_info = DEVICE_ZD1211B },
  78         { USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
  79         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211B },
  80         { USB_DEVICE(0x07fa, 0x1196), .driver_info = DEVICE_ZD1211B },
  81         { USB_DEVICE(0x083a, 0x4505), .driver_info = DEVICE_ZD1211B },
  82         { USB_DEVICE(0x083a, 0xe501), .driver_info = DEVICE_ZD1211B },
  83         { USB_DEVICE(0x083a, 0xe503), .driver_info = DEVICE_ZD1211B },
  84         { USB_DEVICE(0x083a, 0xe506), .driver_info = DEVICE_ZD1211B },
  85         { USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
  86         { USB_DEVICE(0x0ace, 0xb215), .driver_info = DEVICE_ZD1211B },
  87         { USB_DEVICE(0x0b05, 0x171b), .driver_info = DEVICE_ZD1211B },
  88         { USB_DEVICE(0x0baf, 0x0121), .driver_info = DEVICE_ZD1211B },
  89         { USB_DEVICE(0x0cde, 0x001a), .driver_info = DEVICE_ZD1211B },
  90         { USB_DEVICE(0x0df6, 0x0036), .driver_info = DEVICE_ZD1211B },
  91         { USB_DEVICE(0x129b, 0x1667), .driver_info = DEVICE_ZD1211B },
  92         { USB_DEVICE(0x13b1, 0x0024), .driver_info = DEVICE_ZD1211B },
  93         { USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
  94         { USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
  95         { USB_DEVICE(0x2019, 0x5303), .driver_info = DEVICE_ZD1211B },
  96         { USB_DEVICE(0x2019, 0xed01), .driver_info = DEVICE_ZD1211B },
  97         /* "Driverless" devices that need ejecting */
  98         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
  99         { USB_DEVICE(0x0ace, 0x20ff), .driver_info = DEVICE_INSTALLER },
 100         {}
 101 };
 102
 103 MODULE_LICENSE("GPL");
 104 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
 105 MODULE_AUTHOR("Ulrich Kunitz");
 106 MODULE_AUTHOR("Daniel Drake");
 107 MODULE_VERSION("1.0");
 108 MODULE_DEVICE_TABLE(usb, usb_ids);
 109
 110 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
 111 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
 112
 113 /* USB device initialization */
 114 static void int_urb_complete(struct urb *urb);
 115
 116 static int request_fw_file(
 117         const struct firmware **fw, const char *name, struct device *device)
 118 {
 119         int r;
 120
 121         dev_dbg_f(device, "fw name %s\n", name);
 122
 123         r = request_firmware(fw, name, device);
 124         if (r)
 125                 dev_err(device,
 126                        "Could not load firmware file %s. Error number %d\n",
 127                        name, r);
 128         return r;
 129 }
 130
 131 static inline u16 get_bcdDevice(const struct usb_device *udev)
 132 {
 133         return le16_to_cpu(udev->descriptor.bcdDevice);
 134 }
 135
 136 enum upload_code_flags {
 137         REBOOT = 1,
 138 };
 139
 140 /* Ensures that MAX_TRANSFER_SIZE is even. */
 141 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
 142
 143 static int upload_code(struct usb_device *udev,
 144         const u8 *data, size_t size, u16 code_offset, int flags)
 145 {
 146         u8 *p;
 147         int r;
 148
 149         /* USB request blocks need "kmalloced" buffers.
 150          */
 151         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
 152         if (!p) {
 153                 dev_err(&udev->dev, "out of memory\n");
 154                 r = -ENOMEM;
 155                 goto error;
 156         }
 157
 158         size &= ~1;
 159         while (size > 0) {
 160                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
 161                         size : MAX_TRANSFER_SIZE;
 162
 163                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
 164
 165                 memcpy(p, data, transfer_size);
 166                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 167                         USB_REQ_FIRMWARE_DOWNLOAD,
 168                         USB_DIR_OUT | USB_TYPE_VENDOR,
 169                         code_offset, 0, p, transfer_size, 1000 /* ms */);
 170                 if (r < 0) {
 171                         dev_err(&udev->dev,
 172                                "USB control request for firmware upload"
 173                                " failed. Error number %d\n", r);
 174                         goto error;
 175                 }
 176                 transfer_size = r & ~1;
 177
 178                 size -= transfer_size;
 179                 data += transfer_size;
 180                 code_offset += transfer_size/sizeof(u16);
 181         }
 182
 183         if (flags & REBOOT) {
 184                 u8 ret;
 185
 186                 /* Use "DMA-aware" buffer. */
 187                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 188                         USB_REQ_FIRMWARE_CONFIRM,
 189                         USB_DIR_IN | USB_TYPE_VENDOR,
 190                         0, 0, p, sizeof(ret), 5000 /* ms */);
 191                 if (r != sizeof(ret)) {
 192                         dev_err(&udev->dev,
 193                                 "control request firmeware confirmation failed."
 194                                 " Return value %d\n", r);
 195                         if (r >= 0)
 196                                 r = -ENODEV;
 197                         goto error;
 198                 }
 199                 ret = p[0];
 200                 if (ret & 0x80) {
 201                         dev_err(&udev->dev,
 202                                 "Internal error while downloading."
 203                                 " Firmware confirm return value %#04x\n",
 204                                 (unsigned int)ret);
 205                         r = -ENODEV;
 206                         goto error;
 207                 }
 208                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
 209                         (unsigned int)ret);
 210         }
 211
 212         r = 0;
 213 error:
 214         kfree(p);
 215         return r;
 216 }
 217
 218 static u16 get_word(const void *data, u16 offset)
 219 {
 220         const __le16 *p = data;
 221         return le16_to_cpu(p[offset]);
 222 }
 223
 224 static char *get_fw_name(struct zd_usb *usb, char *buffer, size_t size,
 225                        const char* postfix)
 226 {
 227         scnprintf(buffer, size, "%s%s",
 228                 usb->is_zd1211b ?
 229                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
 230                 postfix);
 231         return buffer;
 232 }
 233
 234 static int handle_version_mismatch(struct zd_usb *usb,
 235         const struct firmware *ub_fw)
 236 {
 237         struct usb_device *udev = zd_usb_to_usbdev(usb);
 238         const struct firmware *ur_fw = NULL;
 239         int offset;
 240         int r = 0;
 241         char fw_name[128];
 242
 243         r = request_fw_file(&ur_fw,
 244                 get_fw_name(usb, fw_name, sizeof(fw_name), "ur"),
 245                 &udev->dev);
 246         if (r)
 247                 goto error;
 248
 249         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START, REBOOT);
 250         if (r)
 251                 goto error;
 252
 253         offset = (E2P_BOOT_CODE_OFFSET * sizeof(u16));
 254         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
 255                 E2P_START + E2P_BOOT_CODE_OFFSET, REBOOT);
 256
 257         /* At this point, the vendor driver downloads the whole firmware
 258          * image, hacks around with version IDs, and uploads it again,
 259          * completely overwriting the boot code. We do not do this here as
 260          * it is not required on any tested devices, and it is suspected to
 261          * cause problems. */
 262 error:
 263         release_firmware(ur_fw);
 264         return r;
 265 }
 266
 267 static int upload_firmware(struct zd_usb *usb)
 268 {
 269         int r;
 270         u16 fw_bcdDevice;
 271         u16 bcdDevice;
 272         struct usb_device *udev = zd_usb_to_usbdev(usb);
 273         const struct firmware *ub_fw = NULL;
 274         const struct firmware *uph_fw = NULL;
 275         char fw_name[128];
 276
 277         bcdDevice = get_bcdDevice(udev);
 278
 279         r = request_fw_file(&ub_fw,
 280                 get_fw_name(usb, fw_name, sizeof(fw_name), "ub"),
 281                 &udev->dev);
 282         if (r)
 283                 goto error;
 284
 285         fw_bcdDevice = get_word(ub_fw->data, E2P_DATA_OFFSET);
 286
 287         if (fw_bcdDevice != bcdDevice) {
 288                 dev_info(&udev->dev,
 289                         "firmware version %#06x and device bootcode version "
 290                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
 291                 if (bcdDevice <= 0x4313)
 292                         dev_warn(&udev->dev, "device has old bootcode, please "
 293                                 "report success or failure\n");
 294
 295                 r = handle_version_mismatch(usb, ub_fw);
 296                 if (r)
 297                         goto error;
 298         } else {
 299                 dev_dbg_f(&udev->dev,
 300                         "firmware device id %#06x is equal to the "
 301                         "actual device id\n", fw_bcdDevice);
 302         }
 303
 304
 305         r = request_fw_file(&uph_fw,
 306                 get_fw_name(usb, fw_name, sizeof(fw_name), "uphr"),
 307                 &udev->dev);
 308         if (r)
 309                 goto error;
 310
 311         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START, REBOOT);
 312         if (r) {
 313                 dev_err(&udev->dev,
 314                         "Could not upload firmware code uph. Error number %d\n",
 315                         r);
 316         }
 317
 318         /* FALL-THROUGH */
 319 error:
 320         release_firmware(ub_fw);
 321         release_firmware(uph_fw);
 322         return r;
 323 }
 324
 325 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "ur");
 326 MODULE_FIRMWARE(FW_ZD1211_PREFIX "ur");
 327 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "ub");
 328 MODULE_FIRMWARE(FW_ZD1211_PREFIX "ub");
 329 MODULE_FIRMWARE(FW_ZD1211B_PREFIX "uphr");
 330 MODULE_FIRMWARE(FW_ZD1211_PREFIX "uphr");
 331
 332 /* Read data from device address space using "firmware interface" which does
 333  * not require firmware to be loaded. */
 334 int zd_usb_read_fw(struct zd_usb *usb, zd_addr_t addr, u8 *data, u16 len)
 335 {
 336         int r;
 337         struct usb_device *udev = zd_usb_to_usbdev(usb);
 338         u8 *buf;
 339
 340         /* Use "DMA-aware" buffer. */
 341         buf = kmalloc(len, GFP_KERNEL);
 342         if (!buf)
 343                 return -ENOMEM;
 344         r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 345                 USB_REQ_FIRMWARE_READ_DATA, USB_DIR_IN | 0x40, addr, 0,
 346                 buf, len, 5000);
 347         if (r < 0) {
 348                 dev_err(&udev->dev,
 349                         "read over firmware interface failed: %d\n", r);
 350                 goto exit;
 351         } else if (r != len) {
 352                 dev_err(&udev->dev,
 353                         "incomplete read over firmware interface: %d/%d\n",
 354                         r, len);
 355                 r = -EIO;
 356                 goto exit;
 357         }
 358         r = 0;
 359         memcpy(data, buf, len);
 360 exit:
 361         kfree(buf);
 362         return r;
 363 }
 364
 365 #define urb_dev(urb) (&(urb)->dev->dev)
 366
 367 static inline void handle_regs_int(struct urb *urb)
 368 {
 369         struct zd_usb *usb = urb->context;
 370         struct zd_usb_interrupt *intr = &usb->intr;
 371         int len;
 372         u16 int_num;
 373
 374         ZD_ASSERT(in_interrupt());
 375         spin_lock(&intr->lock);
 376
 377         int_num = le16_to_cpu(*(__le16 *)(urb->transfer_buffer+2));
 378         if (int_num == CR_INTERRUPT) {
 379                 struct zd_mac *mac = zd_hw_mac(zd_usb_to_hw(urb->context));
 380                 spin_lock(&mac->lock);
 381                 memcpy(&mac->intr_buffer, urb->transfer_buffer,
 382                                 USB_MAX_EP_INT_BUFFER);
 383                 spin_unlock(&mac->lock);
 384                 schedule_work(&mac->process_intr);
 385         } else if (intr->read_regs_enabled) {
 386                 intr->read_regs.length = len = urb->actual_length;
 387
 388                 if (len > sizeof(intr->read_regs.buffer))
 389                         len = sizeof(intr->read_regs.buffer);
 390                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
 391                 intr->read_regs_enabled = 0;
 392                 complete(&intr->read_regs.completion);
 393                 goto out;
 394         }
 395
 396 out:
 397         spin_unlock(&intr->lock);
 398 }
 399
 400 static void int_urb_complete(struct urb *urb)
 401 {
 402         int r;
 403         struct usb_int_header *hdr;
 404
 405         switch (urb->status) {
 406         case 0:
 407                 break;
 408         case -ESHUTDOWN:
 409         case -EINVAL:
 410         case -ENODEV:
 411         case -ENOENT:
 412         case -ECONNRESET:
 413         case -EPIPE:
 414                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 415                 return;
 416         default:
 417                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 418                 goto resubmit;
 419         }
 420
 421         if (urb->actual_length < sizeof(hdr)) {
 422                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
 423                 goto resubmit;
 424         }
 425
 426         hdr = urb->transfer_buffer;
 427         if (hdr->type != USB_INT_TYPE) {
 428                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
 429                 goto resubmit;
 430         }
 431
 432         switch (hdr->id) {
 433         case USB_INT_ID_REGS:
 434                 handle_regs_int(urb);
 435                 break;
 436         case USB_INT_ID_RETRY_FAILED:
 437                 zd_mac_tx_failed(urb);
 438                 break;
 439         default:
 440                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
 441                         (unsigned int)hdr->id);
 442                 goto resubmit;
 443         }
 444
 445 resubmit:
 446         r = usb_submit_urb(urb, GFP_ATOMIC);
 447         if (r) {
 448                 dev_dbg_f(urb_dev(urb), "error: resubmit urb %p err code %d\n",
 449                           urb, r);
 450                 /* TODO: add worker to reset intr->urb */
 451         }
 452         return;
 453 }
 454
 455 static inline int int_urb_interval(struct usb_device *udev)
 456 {
 457         switch (udev->speed) {
 458         case USB_SPEED_HIGH:
 459                 return 4;
 460         case USB_SPEED_LOW:
 461                 return 10;
 462         case USB_SPEED_FULL:
 463         default:
 464                 return 1;
 465         }
 466 }
 467
 468 static inline int usb_int_enabled(struct zd_usb *usb)
 469 {
 470         unsigned long flags;
 471         struct zd_usb_interrupt *intr = &usb->intr;
 472         struct urb *urb;
 473
 474         spin_lock_irqsave(&intr->lock, flags);
 475         urb = intr->urb;
 476         spin_unlock_irqrestore(&intr->lock, flags);
 477         return urb != NULL;
 478 }
 479
 480 int zd_usb_enable_int(struct zd_usb *usb)
 481 {
 482         int r;
 483         struct usb_device *udev = zd_usb_to_usbdev(usb);
 484         struct zd_usb_interrupt *intr = &usb->intr;
 485         struct urb *urb;
 486
 487         dev_dbg_f(zd_usb_dev(usb), "\n");
 488
 489         urb = usb_alloc_urb(0, GFP_KERNEL);
 490         if (!urb) {
 491                 r = -ENOMEM;
 492                 goto out;
 493         }
 494
 495         ZD_ASSERT(!irqs_disabled());
 496         spin_lock_irq(&intr->lock);
 497         if (intr->urb) {
 498                 spin_unlock_irq(&intr->lock);
 499                 r = 0;
 500                 goto error_free_urb;
 501         }
 502         intr->urb = urb;
 503         spin_unlock_irq(&intr->lock);
 504
 505         r = -ENOMEM;
 506         intr->buffer = usb_alloc_coherent(udev, USB_MAX_EP_INT_BUFFER,
 507                                           GFP_KERNEL, &intr->buffer_dma);
 508         if (!intr->buffer) {
 509                 dev_dbg_f(zd_usb_dev(usb),
 510                         "couldn't allocate transfer_buffer\n");
 511                 goto error_set_urb_null;
 512         }
 513
 514         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
 515                          intr->buffer, USB_MAX_EP_INT_BUFFER,
 516                          int_urb_complete, usb,
 517                          intr->interval);
 518         urb->transfer_dma = intr->buffer_dma;
 519         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 520
 521         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
 522         r = usb_submit_urb(urb, GFP_KERNEL);
 523         if (r) {
 524                 dev_dbg_f(zd_usb_dev(usb),
 525                          "Couldn't submit urb. Error number %d\n", r);
 526                 goto error;
 527         }
 528
 529         return 0;
 530 error:
 531         usb_free_coherent(udev, USB_MAX_EP_INT_BUFFER,
 532                           intr->buffer, intr->buffer_dma);
 533 error_set_urb_null:
 534         spin_lock_irq(&intr->lock);
 535         intr->urb = NULL;
 536         spin_unlock_irq(&intr->lock);
 537 error_free_urb:
 538         usb_free_urb(urb);
 539 out:
 540         return r;
 541 }
 542
 543 void zd_usb_disable_int(struct zd_usb *usb)
 544 {
 545         unsigned long flags;
 546         struct usb_device *udev = zd_usb_to_usbdev(usb);
 547         struct zd_usb_interrupt *intr = &usb->intr;
 548         struct urb *urb;
 549         void *buffer;
 550         dma_addr_t buffer_dma;
 551
 552         spin_lock_irqsave(&intr->lock, flags);
 553         urb = intr->urb;
 554         if (!urb) {
 555                 spin_unlock_irqrestore(&intr->lock, flags);
 556                 return;
 557         }
 558         intr->urb = NULL;
 559         buffer = intr->buffer;
 560         buffer_dma = intr->buffer_dma;
 561         intr->buffer = NULL;
 562         spin_unlock_irqrestore(&intr->lock, flags);
 563
 564         usb_kill_urb(urb);
 565         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
 566         usb_free_urb(urb);
 567
 568         if (buffer)
 569                 usb_free_coherent(udev, USB_MAX_EP_INT_BUFFER,
 570                                   buffer, buffer_dma);
 571 }
 572
 573 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
 574                              unsigned int length)
 575 {
 576         int i;
 577         const struct rx_length_info *length_info;
 578
 579         if (length < sizeof(struct rx_length_info)) {
 580                 /* It's not a complete packet anyhow. */
 581                 printk("%s: invalid, small RX packet : %d\n",
 582                        __func__, length);
 583                 return;
 584         }
 585         length_info = (struct rx_length_info *)
 586                 (buffer + length - sizeof(struct rx_length_info));
 587
 588         /* It might be that three frames are merged into a single URB
 589          * transaction. We have to check for the length info tag.
 590          *
 591          * While testing we discovered that length_info might be unaligned,
 592          * because if USB transactions are merged, the last packet will not
 593          * be padded. Unaligned access might also happen if the length_info
 594          * structure is not present.
 595          */
 596         if (get_unaligned_le16(&length_info->tag) == RX_LENGTH_INFO_TAG)
 597         {
 598                 unsigned int l, k, n;
 599                 for (i = 0, l = 0;; i++) {
 600                         k = get_unaligned_le16(&length_info->length[i]);
 601                         if (k == 0)
 602                                 return;
 603                         n = l+k;
 604                         if (n > length)
 605                                 return;
 606                         zd_mac_rx(zd_usb_to_hw(usb), buffer+l, k);
 607                         if (i >= 2)
 608                                 return;
 609                         l = (n+3) & ~3;
 610                 }
 611         } else {
 612                 zd_mac_rx(zd_usb_to_hw(usb), buffer, length);
 613         }
 614 }
 615
 616 static void rx_urb_complete(struct urb *urb)
 617 {
 618         int r;
 619         struct zd_usb *usb;
 620         struct zd_usb_rx *rx;
 621         const u8 *buffer;
 622         unsigned int length;
 623
 624         switch (urb->status) {
 625         case 0:
 626                 break;
 627         case -ESHUTDOWN:
 628         case -EINVAL:
 629         case -ENODEV:
 630         case -ENOENT:
 631         case -ECONNRESET:
 632         case -EPIPE:
 633                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 634                 return;
 635         default:
 636                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 637                 goto resubmit;
 638         }
 639
 640         buffer = urb->transfer_buffer;
 641         length = urb->actual_length;
 642         usb = urb->context;
 643         rx = &usb->rx;
 644
 645         zd_usb_reset_rx_idle_timer(usb);
 646
 647         if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
 648                 /* If there is an old first fragment, we don't care. */
 649                 dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
 650                 ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
 651                 spin_lock(&rx->lock);
 652                 memcpy(rx->fragment, buffer, length);
 653                 rx->fragment_length = length;
 654                 spin_unlock(&rx->lock);
 655                 goto resubmit;
 656         }
 657
 658         spin_lock(&rx->lock);
 659         if (rx->fragment_length > 0) {
 660                 /* We are on a second fragment, we believe */
 661                 ZD_ASSERT(length + rx->fragment_length <=
 662                           ARRAY_SIZE(rx->fragment));
 663                 dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
 664                 memcpy(rx->fragment+rx->fragment_length, buffer, length);
 665                 handle_rx_packet(usb, rx->fragment,
 666                                  rx->fragment_length + length);
 667                 rx->fragment_length = 0;
 668                 spin_unlock(&rx->lock);
 669         } else {
 670                 spin_unlock(&rx->lock);
 671                 handle_rx_packet(usb, buffer, length);
 672         }
 673
 674 resubmit:
 675         r = usb_submit_urb(urb, GFP_ATOMIC);
 676         if (r)
 677                 dev_dbg_f(urb_dev(urb), "urb %p resubmit error %d\n", urb, r);
 678 }
 679
 680 static struct urb *alloc_rx_urb(struct zd_usb *usb)
 681 {
 682         struct usb_device *udev = zd_usb_to_usbdev(usb);
 683         struct urb *urb;
 684         void *buffer;
 685
 686         urb = usb_alloc_urb(0, GFP_KERNEL);
 687         if (!urb)
 688                 return NULL;
 689         buffer = usb_alloc_coherent(udev, USB_MAX_RX_SIZE, GFP_KERNEL,
 690                                     &urb->transfer_dma);
 691         if (!buffer) {
 692                 usb_free_urb(urb);
 693                 return NULL;
 694         }
 695
 696         usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
 697                           buffer, USB_MAX_RX_SIZE,
 698                           rx_urb_complete, usb);
 699         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 700
 701         return urb;
 702 }
 703
 704 static void free_rx_urb(struct urb *urb)
 705 {
 706         if (!urb)
 707                 return;
 708         usb_free_coherent(urb->dev, urb->transfer_buffer_length,
 709                           urb->transfer_buffer, urb->transfer_dma);
 710         usb_free_urb(urb);
 711 }
 712
 713 static int __zd_usb_enable_rx(struct zd_usb *usb)
 714 {
 715         int i, r;
 716         struct zd_usb_rx *rx = &usb->rx;
 717         struct urb **urbs;
 718
 719         dev_dbg_f(zd_usb_dev(usb), "\n");
 720
 721         r = -ENOMEM;
 722         urbs = kcalloc(RX_URBS_COUNT, sizeof(struct urb *), GFP_KERNEL);
 723         if (!urbs)
 724                 goto error;
 725         for (i = 0; i < RX_URBS_COUNT; i++) {
 726                 urbs[i] = alloc_rx_urb(usb);
 727                 if (!urbs[i])
 728                         goto error;
 729         }
 730
 731         ZD_ASSERT(!irqs_disabled());
 732         spin_lock_irq(&rx->lock);
 733         if (rx->urbs) {
 734                 spin_unlock_irq(&rx->lock);
 735                 r = 0;
 736                 goto error;
 737         }
 738         rx->urbs = urbs;
 739         rx->urbs_count = RX_URBS_COUNT;
 740         spin_unlock_irq(&rx->lock);
 741
 742         for (i = 0; i < RX_URBS_COUNT; i++) {
 743                 r = usb_submit_urb(urbs[i], GFP_KERNEL);
 744                 if (r)
 745                         goto error_submit;
 746         }
 747
 748         return 0;
 749 error_submit:
 750         for (i = 0; i < RX_URBS_COUNT; i++) {
 751                 usb_kill_urb(urbs[i]);
 752         }
 753         spin_lock_irq(&rx->lock);
 754         rx->urbs = NULL;
 755         rx->urbs_count = 0;
 756         spin_unlock_irq(&rx->lock);
 757 error:
 758         if (urbs) {
 759                 for (i = 0; i < RX_URBS_COUNT; i++)
 760                         free_rx_urb(urbs[i]);
 761         }
 762         return r;
 763 }
 764
 765 int zd_usb_enable_rx(struct zd_usb *usb)
 766 {
 767         int r;
 768         struct zd_usb_rx *rx = &usb->rx;
 769
 770         mutex_lock(&rx->setup_mutex);
 771         r = __zd_usb_enable_rx(usb);
 772         mutex_unlock(&rx->setup_mutex);
 773
 774         zd_usb_reset_rx_idle_timer(usb);
 775
 776         return r;
 777 }
 778
 779 static void __zd_usb_disable_rx(struct zd_usb *usb)
 780 {
 781         int i;
 782         unsigned long flags;
 783         struct urb **urbs;
 784         unsigned int count;
 785         struct zd_usb_rx *rx = &usb->rx;
 786
 787         spin_lock_irqsave(&rx->lock, flags);
 788         urbs = rx->urbs;
 789         count = rx->urbs_count;
 790         spin_unlock_irqrestore(&rx->lock, flags);
 791         if (!urbs)
 792                 return;
 793
 794         for (i = 0; i < count; i++) {
 795                 usb_kill_urb(urbs[i]);
 796                 free_rx_urb(urbs[i]);
 797         }
 798         kfree(urbs);
 799
 800         spin_lock_irqsave(&rx->lock, flags);
 801         rx->urbs = NULL;
 802         rx->urbs_count = 0;
 803         spin_unlock_irqrestore(&rx->lock, flags);
 804 }
 805
 806 void zd_usb_disable_rx(struct zd_usb *usb)
 807 {
 808         struct zd_usb_rx *rx = &usb->rx;
 809
 810         mutex_lock(&rx->setup_mutex);
 811         __zd_usb_disable_rx(usb);
 812         mutex_unlock(&rx->setup_mutex);
 813
 814         cancel_delayed_work_sync(&rx->idle_work);
 815 }
 816
 817 static void zd_usb_reset_rx(struct zd_usb *usb)
 818 {
 819         bool do_reset;
 820         struct zd_usb_rx *rx = &usb->rx;
 821         unsigned long flags;
 822
 823         mutex_lock(&rx->setup_mutex);
 824
 825         spin_lock_irqsave(&rx->lock, flags);
 826         do_reset = rx->urbs != NULL;
 827         spin_unlock_irqrestore(&rx->lock, flags);
 828
 829         if (do_reset) {
 830                 __zd_usb_disable_rx(usb);
 831                 __zd_usb_enable_rx(usb);
 832         }
 833
 834         mutex_unlock(&rx->setup_mutex);
 835
 836         if (do_reset)
 837                 zd_usb_reset_rx_idle_timer(usb);
 838 }
 839
 840 /**
 841  * zd_usb_disable_tx - disable transmission
 842  * @usb: the zd1211rw-private USB structure
 843  *
 844  * Frees all URBs in the free list and marks the transmission as disabled.
 845  */
 846 void zd_usb_disable_tx(struct zd_usb *usb)
 847 {
 848         struct zd_usb_tx *tx = &usb->tx;
 849         unsigned long flags;
 850
 851         atomic_set(&tx->enabled, 0);
 852
 853         /* kill all submitted tx-urbs */
 854         usb_kill_anchored_urbs(&tx->submitted);
 855
 856         spin_lock_irqsave(&tx->lock, flags);
 857         WARN_ON(!skb_queue_empty(&tx->submitted_skbs));
 858         WARN_ON(tx->submitted_urbs != 0);
 859         tx->submitted_urbs = 0;
 860         spin_unlock_irqrestore(&tx->lock, flags);
 861
 862         /* The stopped state is ignored, relying on ieee80211_wake_queues()
 863          * in a potentionally following zd_usb_enable_tx().
 864          */
 865 }
 866
 867 /**
 868  * zd_usb_enable_tx - enables transmission
 869  * @usb: a &struct zd_usb pointer
 870  *
 871  * This function enables transmission and prepares the &zd_usb_tx data
 872  * structure.
 873  */
 874 void zd_usb_enable_tx(struct zd_usb *usb)
 875 {
 876         unsigned long flags;
 877         struct zd_usb_tx *tx = &usb->tx;
 878
 879         spin_lock_irqsave(&tx->lock, flags);
 880         atomic_set(&tx->enabled, 1);
 881         tx->submitted_urbs = 0;
 882         ieee80211_wake_queues(zd_usb_to_hw(usb));
 883         tx->stopped = 0;
 884         spin_unlock_irqrestore(&tx->lock, flags);
 885 }
 886
 887 static void tx_dec_submitted_urbs(struct zd_usb *usb)
 888 {
 889         struct zd_usb_tx *tx = &usb->tx;
 890         unsigned long flags;
 891
 892         spin_lock_irqsave(&tx->lock, flags);
 893         --tx->submitted_urbs;
 894         if (tx->stopped && tx->submitted_urbs <= ZD_USB_TX_LOW) {
 895                 ieee80211_wake_queues(zd_usb_to_hw(usb));
 896                 tx->stopped = 0;
 897         }
 898         spin_unlock_irqrestore(&tx->lock, flags);
 899 }
 900
 901 static void tx_inc_submitted_urbs(struct zd_usb *usb)
 902 {
 903         struct zd_usb_tx *tx = &usb->tx;
 904         unsigned long flags;
 905
 906         spin_lock_irqsave(&tx->lock, flags);
 907         ++tx->submitted_urbs;
 908         if (!tx->stopped && tx->submitted_urbs > ZD_USB_TX_HIGH) {
 909                 ieee80211_stop_queues(zd_usb_to_hw(usb));
 910                 tx->stopped = 1;
 911         }
 912         spin_unlock_irqrestore(&tx->lock, flags);
 913 }
 914
 915 /**
 916  * tx_urb_complete - completes the execution of an URB
 917  * @urb: a URB
 918  *
 919  * This function is called if the URB has been transferred to a device or an
 920  * error has happened.
 921  */
 922 static void tx_urb_complete(struct urb *urb)
 923 {
 924         int r;
 925         struct sk_buff *skb;
 926         struct ieee80211_tx_info *info;
 927         struct zd_usb *usb;
 928         struct zd_usb_tx *tx;
 929
 930         skb = (struct sk_buff *)urb->context;
 931         info = IEEE80211_SKB_CB(skb);
 932         /*
 933          * grab 'usb' pointer before handing off the skb (since
 934          * it might be freed by zd_mac_tx_to_dev or mac80211)
 935          */
 936         usb = &zd_hw_mac(info->rate_driver_data[0])->chip.usb;
 937         tx = &usb->tx;
 938
 939         switch (urb->status) {
 940         case 0:
 941                 break;
 942         case -ESHUTDOWN:
 943         case -EINVAL:
 944         case -ENODEV:
 945         case -ENOENT:
 946         case -ECONNRESET:
 947         case -EPIPE:
 948                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 949                 break;
 950         default:
 951                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 952                 goto resubmit;
 953         }
 954 free_urb:
 955         skb_unlink(skb, &usb->tx.submitted_skbs);
 956         zd_mac_tx_to_dev(skb, urb->status);
 957         usb_free_urb(urb);
 958         tx_dec_submitted_urbs(usb);
 959         return;
 960 resubmit:
 961         usb_anchor_urb(urb, &tx->submitted);
 962         r = usb_submit_urb(urb, GFP_ATOMIC);
 963         if (r) {
 964                 usb_unanchor_urb(urb);
 965                 dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
 966                 goto free_urb;
 967         }
 968 }
 969
 970 /**
 971  * zd_usb_tx: initiates transfer of a frame of the device
 972  *
 973  * @usb: the zd1211rw-private USB structure
 974  * @skb: a &struct sk_buff pointer
 975  *
 976  * This function tranmits a frame to the device. It doesn't wait for
 977  * completion. The frame must contain the control set and have all the
 978  * control set information available.
 979  *
 980  * The function returns 0 if the transfer has been successfully initiated.
 981  */
 982 int zd_usb_tx(struct zd_usb *usb, struct sk_buff *skb)
 983 {
 984         int r;
 985         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 986         struct usb_device *udev = zd_usb_to_usbdev(usb);
 987         struct urb *urb;
 988         struct zd_usb_tx *tx = &usb->tx;
 989
 990         if (!atomic_read(&tx->enabled)) {
 991                 r = -ENOENT;
 992                 goto out;
 993         }
 994
 995         urb = usb_alloc_urb(0, GFP_ATOMIC);
 996         if (!urb) {
 997                 r = -ENOMEM;
 998                 goto out;
 999         }
1000
1001         usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
1002                           skb->data, skb->len, tx_urb_complete, skb);
1003
1004         info->rate_driver_data[1] = (void *)jiffies;
1005         skb_queue_tail(&tx->submitted_skbs, skb);
1006         usb_anchor_urb(urb, &tx->submitted);
1007
1008         r = usb_submit_urb(urb, GFP_ATOMIC);
1009         if (r) {
1010                 dev_dbg_f(zd_usb_dev(usb), "error submit urb %p %d\n", urb, r);
1011                 usb_unanchor_urb(urb);
1012                 skb_unlink(skb, &tx->submitted_skbs);
1013                 goto error;
1014         }
1015         tx_inc_submitted_urbs(usb);
1016         return 0;
1017 error:
1018         usb_free_urb(urb);
1019 out:
1020         return r;
1021 }
1022
1023 static bool zd_tx_timeout(struct zd_usb *usb)
1024 {
1025         struct zd_usb_tx *tx = &usb->tx;
1026         struct sk_buff_head *q = &tx->submitted_skbs;
1027         struct sk_buff *skb, *skbnext;
1028         struct ieee80211_tx_info *info;
1029         unsigned long flags, trans_start;
1030         bool have_timedout = false;
1031
1032         spin_lock_irqsave(&q->lock, flags);
1033         skb_queue_walk_safe(q, skb, skbnext) {
1034                 info = IEEE80211_SKB_CB(skb);
1035                 trans_start = (unsigned long)info->rate_driver_data[1];
1036
1037                 if (time_is_before_jiffies(trans_start + ZD_TX_TIMEOUT)) {
1038                         have_timedout = true;
1039                         break;
1040                 }
1041         }
1042         spin_unlock_irqrestore(&q->lock, flags);
1043
1044         return have_timedout;
1045 }
1046
1047 static void zd_tx_watchdog_handler(struct work_struct *work)
1048 {
1049         struct zd_usb *usb =
1050                 container_of(work, struct zd_usb, tx.watchdog_work.work);
1051         struct zd_usb_tx *tx = &usb->tx;
1052
1053         if (!atomic_read(&tx->enabled) || !tx->watchdog_enabled)
1054                 goto out;
1055         if (!zd_tx_timeout(usb))
1056                 goto out;
1057
1058         /* TX halted, try reset */
1059         dev_warn(zd_usb_dev(usb), "TX-stall detected, reseting device...");
1060
1061         usb_queue_reset_device(usb->intf);
1062
1063         /* reset will stop this worker, don't rearm */
1064         return;
1065 out:
1066         queue_delayed_work(zd_workqueue, &tx->watchdog_work,
1067                            ZD_TX_WATCHDOG_INTERVAL);
1068 }
1069
1070 void zd_tx_watchdog_enable(struct zd_usb *usb)
1071 {
1072         struct zd_usb_tx *tx = &usb->tx;
1073
1074         if (!tx->watchdog_enabled) {
1075                 dev_dbg_f(zd_usb_dev(usb), "\n");
1076                 queue_delayed_work(zd_workqueue, &tx->watchdog_work,
1077                                    ZD_TX_WATCHDOG_INTERVAL);
1078                 tx->watchdog_enabled = 1;
1079         }
1080 }
1081
1082 void zd_tx_watchdog_disable(struct zd_usb *usb)
1083 {
1084         struct zd_usb_tx *tx = &usb->tx;
1085
1086         if (tx->watchdog_enabled) {
1087                 dev_dbg_f(zd_usb_dev(usb), "\n");
1088                 tx->watchdog_enabled = 0;
1089                 cancel_delayed_work_sync(&tx->watchdog_work);
1090         }
1091 }
1092
1093 static void zd_rx_idle_timer_handler(struct work_struct *work)
1094 {
1095         struct zd_usb *usb =
1096                 container_of(work, struct zd_usb, rx.idle_work.work);
1097         struct zd_mac *mac = zd_usb_to_mac(usb);
1098
1099         if (!test_bit(ZD_DEVICE_RUNNING, &mac->flags))
1100                 return;
1101
1102         dev_dbg_f(zd_usb_dev(usb), "\n");
1103
1104         /* 30 seconds since last rx, reset rx */
1105         zd_usb_reset_rx(usb);
1106 }
1107
1108 void zd_usb_reset_rx_idle_timer(struct zd_usb *usb)
1109 {
1110         struct zd_usb_rx *rx = &usb->rx;
1111
1112         cancel_delayed_work(&rx->idle_work);
1113         queue_delayed_work(zd_workqueue, &rx->idle_work, ZD_RX_IDLE_INTERVAL);
1114 }
1115
1116 static inline void init_usb_interrupt(struct zd_usb *usb)
1117 {
1118         struct zd_usb_interrupt *intr = &usb->intr;
1119
1120         spin_lock_init(&intr->lock);
1121         intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
1122         init_completion(&intr->read_regs.completion);
1123         intr->read_regs.cr_int_addr = cpu_to_le16((u16)CR_INTERRUPT);
1124 }
1125
1126 static inline void init_usb_rx(struct zd_usb *usb)
1127 {
1128         struct zd_usb_rx *rx = &usb->rx;
1129         spin_lock_init(&rx->lock);
1130         mutex_init(&rx->setup_mutex);
1131         if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
1132                 rx->usb_packet_size = 512;
1133         } else {
1134                 rx->usb_packet_size = 64;
1135         }
1136         ZD_ASSERT(rx->fragment_length == 0);
1137         INIT_DELAYED_WORK(&rx->idle_work, zd_rx_idle_timer_handler);
1138 }
1139
1140 static inline void init_usb_tx(struct zd_usb *usb)
1141 {
1142         struct zd_usb_tx *tx = &usb->tx;
1143         spin_lock_init(&tx->lock);
1144         atomic_set(&tx->enabled, 0);
1145         tx->stopped = 0;
1146         skb_queue_head_init(&tx->submitted_skbs);
1147         init_usb_anchor(&tx->submitted);
1148         tx->submitted_urbs = 0;
1149         tx->watchdog_enabled = 0;
1150         INIT_DELAYED_WORK(&tx->watchdog_work, zd_tx_watchdog_handler);
1151 }
1152
1153 void zd_usb_init(struct zd_usb *usb, struct ieee80211_hw *hw,
1154                  struct usb_interface *intf)
1155 {
1156         memset(usb, 0, sizeof(*usb));
1157         usb->intf = usb_get_intf(intf);
1158         usb_set_intfdata(usb->intf, hw);
1159         init_usb_anchor(&usb->submitted_cmds);
1160         init_usb_interrupt(usb);
1161         init_usb_tx(usb);
1162         init_usb_rx(usb);
1163 }
1164
1165 void zd_usb_clear(struct zd_usb *usb)
1166 {
1167         usb_set_intfdata(usb->intf, NULL);
1168         usb_put_intf(usb->intf);
1169         ZD_MEMCLEAR(usb, sizeof(*usb));
1170         /* FIXME: usb_interrupt, usb_tx, usb_rx? */
1171 }
1172
1173 static const char *speed(enum usb_device_speed speed)
1174 {
1175         switch (speed) {
1176         case USB_SPEED_LOW:
1177                 return "low";
1178         case USB_SPEED_FULL:
1179                 return "full";
1180         case USB_SPEED_HIGH:
1181                 return "high";
1182         default:
1183                 return "unknown speed";
1184         }
1185 }
1186
1187 static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
1188 {
1189         return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
1190                 le16_to_cpu(udev->descriptor.idVendor),
1191                 le16_to_cpu(udev->descriptor.idProduct),
1192                 get_bcdDevice(udev),
1193                 speed(udev->speed));
1194 }
1195
1196 int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
1197 {
1198         struct usb_device *udev = interface_to_usbdev(usb->intf);
1199         return scnprint_id(udev, buffer, size);
1200 }
1201
1202 #ifdef DEBUG
1203 static void print_id(struct usb_device *udev)
1204 {
1205         char buffer[40];
1206
1207         scnprint_id(udev, buffer, sizeof(buffer));
1208         buffer[sizeof(buffer)-1] = 0;
1209         dev_dbg_f(&udev->dev, "%s\n", buffer);
1210 }
1211 #else
1212 #define print_id(udev) do { } while (0)
1213 #endif
1214
1215 static int eject_installer(struct usb_interface *intf)
1216 {
1217         struct usb_device *udev = interface_to_usbdev(intf);
1218         struct usb_host_interface *iface_desc = &intf->altsetting[0];
1219         struct usb_endpoint_descriptor *endpoint;
1220         unsigned char *cmd;
1221         u8 bulk_out_ep;
1222         int r;
1223
1224         /* Find bulk out endpoint */
1225         for (r = 1; r >= 0; r--) {
1226                 endpoint = &iface_desc->endpoint[r].desc;
1227                 if (usb_endpoint_dir_out(endpoint) &&
1228                     usb_endpoint_xfer_bulk(endpoint)) {
1229                         bulk_out_ep = endpoint->bEndpointAddress;
1230                         break;
1231                 }
1232         }
1233         if (r == -1) {
1234                 dev_err(&udev->dev,
1235                         "zd1211rw: Could not find bulk out endpoint\n");
1236                 return -ENODEV;
1237         }
1238
1239         cmd = kzalloc(31, GFP_KERNEL);
1240         if (cmd == NULL)
1241                 return -ENODEV;
1242
1243         /* USB bulk command block */
1244         cmd[0] = 0x55;  /* bulk command signature */
1245         cmd[1] = 0x53;  /* bulk command signature */
1246         cmd[2] = 0x42;  /* bulk command signature */
1247         cmd[3] = 0x43;  /* bulk command signature */
1248         cmd[14] = 6;    /* command length */
1249
1250         cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
1251         cmd[19] = 0x2;  /* eject disc */
1252
1253         dev_info(&udev->dev, "Ejecting virtual installer media...\n");
1254         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
1255                 cmd, 31, NULL, 2000);
1256         kfree(cmd);
1257         if (r)
1258                 return r;
1259
1260         /* At this point, the device disconnects and reconnects with the real
1261          * ID numbers. */
1262
1263         usb_set_intfdata(intf, NULL);
1264         return 0;
1265 }
1266
1267 int zd_usb_init_hw(struct zd_usb *usb)
1268 {
1269         int r;
1270         struct zd_mac *mac = zd_usb_to_mac(usb);
1271
1272         dev_dbg_f(zd_usb_dev(usb), "\n");
1273
1274         r = upload_firmware(usb);
1275         if (r) {
1276                 dev_err(zd_usb_dev(usb),
1277                        "couldn't load firmware. Error number %d\n", r);
1278                 return r;
1279         }
1280
1281         r = usb_reset_configuration(zd_usb_to_usbdev(usb));
1282         if (r) {
1283                 dev_dbg_f(zd_usb_dev(usb),
1284                         "couldn't reset configuration. Error number %d\n", r);
1285                 return r;
1286         }
1287
1288         r = zd_mac_init_hw(mac->hw);
1289         if (r) {
1290                 dev_dbg_f(zd_usb_dev(usb),
1291                          "couldn't initialize mac. Error number %d\n", r);
1292                 return r;
1293         }
1294
1295         usb->initialized = 1;
1296         return 0;
1297 }
1298
1299 static int probe(struct usb_interface *intf, const struct usb_device_id *id)
1300 {
1301         int r;
1302         struct usb_device *udev = interface_to_usbdev(intf);
1303         struct zd_usb *usb;
1304         struct ieee80211_hw *hw = NULL;
1305
1306         print_id(udev);
1307
1308         if (id->driver_info & DEVICE_INSTALLER)
1309                 return eject_installer(intf);
1310
1311         switch (udev->speed) {
1312         case USB_SPEED_LOW:
1313         case USB_SPEED_FULL:
1314         case USB_SPEED_HIGH:
1315                 break;
1316         default:
1317                 dev_dbg_f(&intf->dev, "Unknown USB speed\n");
1318                 r = -ENODEV;
1319                 goto error;
1320         }
1321
1322         r = usb_reset_device(udev);
1323         if (r) {
1324                 dev_err(&intf->dev,
1325                         "couldn't reset usb device. Error number %d\n", r);
1326                 goto error;
1327         }
1328
1329         hw = zd_mac_alloc_hw(intf);
1330         if (hw == NULL) {
1331                 r = -ENOMEM;
1332                 goto error;
1333         }
1334
1335         usb = &zd_hw_mac(hw)->chip.usb;
1336         usb->is_zd1211b = (id->driver_info == DEVICE_ZD1211B) != 0;
1337
1338         r = zd_mac_preinit_hw(hw);
1339         if (r) {
1340                 dev_dbg_f(&intf->dev,
1341                          "couldn't initialize mac. Error number %d\n", r);
1342                 goto error;
1343         }
1344
1345         r = ieee80211_register_hw(hw);
1346         if (r) {
1347                 dev_dbg_f(&intf->dev,
1348                          "couldn't register device. Error number %d\n", r);
1349                 goto error;
1350         }
1351
1352         dev_dbg_f(&intf->dev, "successful\n");
1353         dev_info(&intf->dev, "%s\n", wiphy_name(hw->wiphy));
1354         return 0;
1355 error:
1356         usb_reset_device(interface_to_usbdev(intf));
1357         if (hw) {
1358                 zd_mac_clear(zd_hw_mac(hw));
1359                 ieee80211_free_hw(hw);
1360         }
1361         return r;
1362 }
1363
1364 static void disconnect(struct usb_interface *intf)
1365 {
1366         struct ieee80211_hw *hw = zd_intf_to_hw(intf);
1367         struct zd_mac *mac;
1368         struct zd_usb *usb;
1369
1370         /* Either something really bad happened, or we're just dealing with
1371          * a DEVICE_INSTALLER. */
1372         if (hw == NULL)
1373                 return;
1374
1375         mac = zd_hw_mac(hw);
1376         usb = &mac->chip.usb;
1377
1378         dev_dbg_f(zd_usb_dev(usb), "\n");
1379
1380         ieee80211_unregister_hw(hw);
1381
1382         /* Just in case something has gone wrong! */
1383         zd_usb_disable_tx(usb);
1384         zd_usb_disable_rx(usb);
1385         zd_usb_disable_int(usb);
1386
1387         /* If the disconnect has been caused by a removal of the
1388          * driver module, the reset allows reloading of the driver. If the
1389          * reset will not be executed here, the upload of the firmware in the
1390          * probe function caused by the reloading of the driver will fail.
1391          */
1392         usb_reset_device(interface_to_usbdev(intf));
1393
1394         zd_mac_clear(mac);
1395         ieee80211_free_hw(hw);
1396         dev_dbg(&intf->dev, "disconnected\n");
1397 }
1398
1399 static void zd_usb_resume(struct zd_usb *usb)
1400 {
1401         struct zd_mac *mac = zd_usb_to_mac(usb);
1402         int r;
1403
1404         dev_dbg_f(zd_usb_dev(usb), "\n");
1405
1406         r = zd_op_start(zd_usb_to_hw(usb));
1407         if (r < 0) {
1408                 dev_warn(zd_usb_dev(usb), "Device resume failed "
1409                          "with error code %d. Retrying...\n", r);
1410                 if (usb->was_running)
1411                         set_bit(ZD_DEVICE_RUNNING, &mac->flags);
1412                 usb_queue_reset_device(usb->intf);
1413                 return;
1414         }
1415
1416         if (mac->type != NL80211_IFTYPE_UNSPECIFIED) {
1417                 r = zd_restore_settings(mac);
1418                 if (r < 0) {
1419                         dev_dbg(zd_usb_dev(usb),
1420                                 "failed to restore settings, %d\n", r);
1421                         return;
1422                 }
1423         }
1424 }
1425
1426 static void zd_usb_stop(struct zd_usb *usb)
1427 {
1428         dev_dbg_f(zd_usb_dev(usb), "\n");
1429
1430         zd_op_stop(zd_usb_to_hw(usb));
1431
1432         zd_usb_disable_tx(usb);
1433         zd_usb_disable_rx(usb);
1434         zd_usb_disable_int(usb);
1435
1436         usb->initialized = 0;
1437 }
1438
1439 static int pre_reset(struct usb_interface *intf)
1440 {
1441         struct ieee80211_hw *hw = usb_get_intfdata(intf);
1442         struct zd_mac *mac;
1443         struct zd_usb *usb;
1444
1445         if (!hw || intf->condition != USB_INTERFACE_BOUND)
1446                 return 0;
1447
1448         mac = zd_hw_mac(hw);
1449         usb = &mac->chip.usb;
1450
1451         usb->was_running = test_bit(ZD_DEVICE_RUNNING, &mac->flags);
1452
1453         zd_usb_stop(usb);
1454
1455         mutex_lock(&mac->chip.mutex);
1456         return 0;
1457 }
1458
1459 static int post_reset(struct usb_interface *intf)
1460 {
1461         struct ieee80211_hw *hw = usb_get_intfdata(intf);
1462         struct zd_mac *mac;
1463         struct zd_usb *usb;
1464
1465         if (!hw || intf->condition != USB_INTERFACE_BOUND)
1466                 return 0;
1467
1468         mac = zd_hw_mac(hw);
1469         usb = &mac->chip.usb;
1470
1471         mutex_unlock(&mac->chip.mutex);
1472
1473         if (usb->was_running)
1474                 zd_usb_resume(usb);
1475         return 0;
1476 }
1477
1478 static struct usb_driver driver = {
1479         .name           = KBUILD_MODNAME,
1480         .id_table       = usb_ids,
1481         .probe          = probe,
1482         .disconnect     = disconnect,
1483         .pre_reset      = pre_reset,
1484         .post_reset     = post_reset,
1485 };
1486
1487 struct workqueue_struct *zd_workqueue;
1488
1489 static int __init usb_init(void)
1490 {
1491         int r;
1492
1493         pr_debug("%s usb_init()\n", driver.name);
1494
1495         zd_workqueue = create_singlethread_workqueue(driver.name);
1496         if (zd_workqueue == NULL) {
1497                 printk(KERN_ERR "%s couldn't create workqueue\n", driver.name);
1498                 return -ENOMEM;
1499         }
1500
1501         r = usb_register(&driver);
1502         if (r) {
1503                 destroy_workqueue(zd_workqueue);
1504                 printk(KERN_ERR "%s usb_register() failed. Error number %d\n",
1505                        driver.name, r);
1506                 return r;
1507         }
1508
1509         pr_debug("%s initialized\n", driver.name);
1510         return 0;
1511 }
1512
1513 static void __exit usb_exit(void)
1514 {
1515         pr_debug("%s usb_exit()\n", driver.name);
1516         usb_deregister(&driver);
1517         destroy_workqueue(zd_workqueue);
1518 }
1519
1520 module_init(usb_init);
1521 module_exit(usb_exit);
1522
1523 static int usb_int_regs_length(unsigned int count)
1524 {
1525         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1526 }
1527
1528 static void prepare_read_regs_int(struct zd_usb *usb)
1529 {
1530         struct zd_usb_interrupt *intr = &usb->intr;
1531
1532         spin_lock_irq(&intr->lock);
1533         intr->read_regs_enabled = 1;
1534         INIT_COMPLETION(intr->read_regs.completion);
1535         spin_unlock_irq(&intr->lock);
1536 }
1537
1538 static void disable_read_regs_int(struct zd_usb *usb)
1539 {
1540         struct zd_usb_interrupt *intr = &usb->intr;
1541
1542         spin_lock_irq(&intr->lock);
1543         intr->read_regs_enabled = 0;
1544         spin_unlock_irq(&intr->lock);
1545 }
1546
1547 static int get_results(struct zd_usb *usb, u16 *values,
1548                        struct usb_req_read_regs *req, unsigned int count)
1549 {
1550         int r;
1551         int i;
1552         struct zd_usb_interrupt *intr = &usb->intr;
1553         struct read_regs_int *rr = &intr->read_regs;
1554         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1555
1556         spin_lock_irq(&intr->lock);
1557
1558         r = -EIO;
1559         /* The created block size seems to be larger than expected.
1560          * However results appear to be correct.
1561          */
1562         if (rr->length < usb_int_regs_length(count)) {
1563                 dev_dbg_f(zd_usb_dev(usb),
1564                          "error: actual length %d less than expected %d\n",
1565                          rr->length, usb_int_regs_length(count));
1566                 goto error_unlock;
1567         }
1568         if (rr->length > sizeof(rr->buffer)) {
1569                 dev_dbg_f(zd_usb_dev(usb),
1570                          "error: actual length %d exceeds buffer size %zu\n",
1571                          rr->length, sizeof(rr->buffer));
1572                 goto error_unlock;
1573         }
1574
1575         for (i = 0; i < count; i++) {
1576                 struct reg_data *rd = &regs->regs[i];
1577                 if (rd->addr != req->addr[i]) {
1578                         dev_dbg_f(zd_usb_dev(usb),
1579                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1580                                  le16_to_cpu(rd->addr),
1581                                  le16_to_cpu(req->addr[i]));
1582                         goto error_unlock;
1583                 }
1584                 values[i] = le16_to_cpu(rd->value);
1585         }
1586
1587         r = 0;
1588 error_unlock:
1589         spin_unlock_irq(&intr->lock);
1590         return r;
1591 }
1592
1593 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1594                      const zd_addr_t *addresses, unsigned int count)
1595 {
1596         int r;
1597         int i, req_len, actual_req_len;
1598         struct usb_device *udev;
1599         struct usb_req_read_regs *req = NULL;
1600         unsigned long timeout;
1601
1602         if (count < 1) {
1603                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1604                 return -EINVAL;
1605         }
1606         if (count > USB_MAX_IOREAD16_COUNT) {
1607                 dev_dbg_f(zd_usb_dev(usb),
1608                          "error: count %u exceeds possible max %u\n",
1609                          count, USB_MAX_IOREAD16_COUNT);
1610                 return -EINVAL;
1611         }
1612         if (in_atomic()) {
1613                 dev_dbg_f(zd_usb_dev(usb),
1614                          "error: io in atomic context not supported\n");
1615                 return -EWOULDBLOCK;
1616         }
1617         if (!usb_int_enabled(usb)) {
1618                 dev_dbg_f(zd_usb_dev(usb),
1619                           "error: usb interrupt not enabled\n");
1620                 return -EWOULDBLOCK;
1621         }
1622
1623         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1624         BUILD_BUG_ON(sizeof(struct usb_req_read_regs) + USB_MAX_IOREAD16_COUNT *
1625                      sizeof(__le16) > sizeof(usb->req_buf));
1626         BUG_ON(sizeof(struct usb_req_read_regs) + count * sizeof(__le16) >
1627                sizeof(usb->req_buf));
1628
1629         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1630         req = (void *)usb->req_buf;
1631
1632         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1633         for (i = 0; i < count; i++)
1634                 req->addr[i] = cpu_to_le16((u16)addresses[i]);
1635
1636         udev = zd_usb_to_usbdev(usb);
1637         prepare_read_regs_int(usb);
1638         r = usb_interrupt_msg(udev, usb_sndintpipe(udev, EP_REGS_OUT),
1639                               req, req_len, &actual_req_len, 50 /* ms */);
1640         if (r) {
1641                 dev_dbg_f(zd_usb_dev(usb),
1642                         "error in usb_interrupt_msg(). Error number %d\n", r);
1643                 goto error;
1644         }
1645         if (req_len != actual_req_len) {
1646                 dev_dbg_f(zd_usb_dev(usb), "error in usb_interrupt_msg()\n"
1647                         " req_len %d != actual_req_len %d\n",
1648                         req_len, actual_req_len);
1649                 r = -EIO;
1650                 goto error;
1651         }
1652
1653         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1654                                               msecs_to_jiffies(50));
1655         if (!timeout) {
1656                 disable_read_regs_int(usb);
1657                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1658                 r = -ETIMEDOUT;
1659                 goto error;
1660         }
1661
1662         r = get_results(usb, values, req, count);
1663 error:
1664         return r;
1665 }
1666
1667 static void iowrite16v_urb_complete(struct urb *urb)
1668 {
1669         struct zd_usb *usb = urb->context;
1670
1671         if (urb->status && !usb->cmd_error)
1672                 usb->cmd_error = urb->status;
1673 }
1674
1675 static int zd_submit_waiting_urb(struct zd_usb *usb, bool last)
1676 {
1677         int r = 0;
1678         struct urb *urb = usb->urb_async_waiting;
1679
1680         if (!urb)
1681                 return 0;
1682
1683         usb->urb_async_waiting = NULL;
1684
1685         if (!last)
1686                 urb->transfer_flags |= URB_NO_INTERRUPT;
1687
1688         usb_anchor_urb(urb, &usb->submitted_cmds);
1689         r = usb_submit_urb(urb, GFP_KERNEL);
1690         if (r) {
1691                 usb_unanchor_urb(urb);
1692                 dev_dbg_f(zd_usb_dev(usb),
1693                         "error in usb_submit_urb(). Error number %d\n", r);
1694                 goto error;
1695         }
1696
1697         /* fall-through with r == 0 */
1698 error:
1699         usb_free_urb(urb);
1700         return r;
1701 }
1702
1703 void zd_usb_iowrite16v_async_start(struct zd_usb *usb)
1704 {
1705         ZD_ASSERT(usb_anchor_empty(&usb->submitted_cmds));
1706         ZD_ASSERT(usb->urb_async_waiting == NULL);
1707         ZD_ASSERT(!usb->in_async);
1708
1709         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1710
1711         usb->in_async = 1;
1712         usb->cmd_error = 0;
1713         usb->urb_async_waiting = NULL;
1714 }
1715
1716 int zd_usb_iowrite16v_async_end(struct zd_usb *usb, unsigned int timeout)
1717 {
1718         int r;
1719
1720         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1721         ZD_ASSERT(usb->in_async);
1722
1723         /* Submit last iowrite16v URB */
1724         r = zd_submit_waiting_urb(usb, true);
1725         if (r) {
1726                 dev_dbg_f(zd_usb_dev(usb),
1727                         "error in zd_submit_waiting_usb(). "
1728                         "Error number %d\n", r);
1729
1730                 usb_kill_anchored_urbs(&usb->submitted_cmds);
1731                 goto error;
1732         }
1733
1734         if (timeout)
1735                 timeout = usb_wait_anchor_empty_timeout(&usb->submitted_cmds,
1736                                                         timeout);
1737         if (!timeout) {
1738                 usb_kill_anchored_urbs(&usb->submitted_cmds);
1739                 if (usb->cmd_error == -ENOENT) {
1740                         dev_dbg_f(zd_usb_dev(usb), "timed out");
1741                         r = -ETIMEDOUT;
1742                         goto error;
1743                 }
1744         }
1745
1746         r = usb->cmd_error;
1747 error:
1748         usb->in_async = 0;
1749         return r;
1750 }
1751
1752 int zd_usb_iowrite16v_async(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1753                             unsigned int count)
1754 {
1755         int r;
1756         struct usb_device *udev;
1757         struct usb_req_write_regs *req = NULL;
1758         int i, req_len;
1759         struct urb *urb;
1760         struct usb_host_endpoint *ep;
1761
1762         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1763         ZD_ASSERT(usb->in_async);
1764
1765         if (count == 0)
1766                 return 0;
1767         if (count > USB_MAX_IOWRITE16_COUNT) {
1768                 dev_dbg_f(zd_usb_dev(usb),
1769                         "error: count %u exceeds possible max %u\n",
1770                         count, USB_MAX_IOWRITE16_COUNT);
1771                 return -EINVAL;
1772         }
1773         if (in_atomic()) {
1774                 dev_dbg_f(zd_usb_dev(usb),
1775                         "error: io in atomic context not supported\n");
1776                 return -EWOULDBLOCK;
1777         }
1778
1779         udev = zd_usb_to_usbdev(usb);
1780
1781         ep = usb_pipe_endpoint(udev, usb_sndintpipe(udev, EP_REGS_OUT));
1782         if (!ep)
1783                 return -ENOENT;
1784
1785         urb = usb_alloc_urb(0, GFP_KERNEL);
1786         if (!urb)
1787                 return -ENOMEM;
1788
1789         req_len = sizeof(struct usb_req_write_regs) +
1790                   count * sizeof(struct reg_data);
1791         req = kmalloc(req_len, GFP_KERNEL);
1792         if (!req) {
1793                 r = -ENOMEM;
1794                 goto error;
1795         }
1796
1797         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1798         for (i = 0; i < count; i++) {
1799                 struct reg_data *rw  = &req->reg_writes[i];
1800                 rw->addr = cpu_to_le16((u16)ioreqs[i].addr);
1801                 rw->value = cpu_to_le16(ioreqs[i].value);
1802         }
1803
1804         usb_fill_int_urb(urb, udev, usb_sndintpipe(udev, EP_REGS_OUT),
1805                          req, req_len, iowrite16v_urb_complete, usb,
1806                          ep->desc.bInterval);
1807         urb->transfer_flags |= URB_FREE_BUFFER | URB_SHORT_NOT_OK;
1808
1809         /* Submit previous URB */
1810         r = zd_submit_waiting_urb(usb, false);
1811         if (r) {
1812                 dev_dbg_f(zd_usb_dev(usb),
1813                         "error in zd_submit_waiting_usb(). "
1814                         "Error number %d\n", r);
1815                 goto error;
1816         }
1817
1818         /* Delay submit so that URB_NO_INTERRUPT flag can be set for all URBs
1819          * of currect batch except for very last.
1820          */
1821         usb->urb_async_waiting = urb;
1822         return 0;
1823 error:
1824         usb_free_urb(urb);
1825         return r;
1826 }
1827
1828 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1829                         unsigned int count)
1830 {
1831         int r;
1832
1833         zd_usb_iowrite16v_async_start(usb);
1834         r = zd_usb_iowrite16v_async(usb, ioreqs, count);
1835         if (r) {
1836                 zd_usb_iowrite16v_async_end(usb, 0);
1837                 return r;
1838         }
1839         return zd_usb_iowrite16v_async_end(usb, 50 /* ms */);
1840 }
1841
1842 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1843 {
1844         int r;
1845         struct usb_device *udev;
1846         struct usb_req_rfwrite *req = NULL;
1847         int i, req_len, actual_req_len;
1848         u16 bit_value_template;
1849
1850         if (in_atomic()) {
1851                 dev_dbg_f(zd_usb_dev(usb),
1852                         "error: io in atomic context not supported\n");
1853                 return -EWOULDBLOCK;
1854         }
1855         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1856                 dev_dbg_f(zd_usb_dev(usb),
1857                         "error: bits %d are smaller than"
1858                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1859                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1860                 return -EINVAL;
1861         }
1862         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1863                 dev_dbg_f(zd_usb_dev(usb),
1864                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1865                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1866                 return -EINVAL;
1867         }
1868 #ifdef DEBUG
1869         if (value & (~0UL << bits)) {
1870                 dev_dbg_f(zd_usb_dev(usb),
1871                         "error: value %#09x has bits >= %d set\n",
1872                         value, bits);
1873                 return -EINVAL;
1874         }
1875 #endif /* DEBUG */
1876
1877         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1878
1879         r = zd_usb_ioread16(usb, &bit_value_template, CR203);
1880         if (r) {
1881                 dev_dbg_f(zd_usb_dev(usb),
1882                         "error %d: Couldn't read CR203\n", r);
1883                 return r;
1884         }
1885         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1886
1887         ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex));
1888         BUILD_BUG_ON(sizeof(struct usb_req_rfwrite) +
1889                      USB_MAX_RFWRITE_BIT_COUNT * sizeof(__le16) >
1890                      sizeof(usb->req_buf));
1891         BUG_ON(sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16) >
1892                sizeof(usb->req_buf));
1893
1894         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1895         req = (void *)usb->req_buf;
1896
1897         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1898         /* 1: 3683a, but not used in ZYDAS driver */
1899         req->value = cpu_to_le16(2);
1900         req->bits = cpu_to_le16(bits);
1901
1902         for (i = 0; i < bits; i++) {
1903                 u16 bv = bit_value_template;
1904                 if (value & (1 << (bits-1-i)))
1905                         bv |= RF_DATA;
1906                 req->bit_values[i] = cpu_to_le16(bv);
1907         }
1908
1909         udev = zd_usb_to_usbdev(usb);
1910         r = usb_interrupt_msg(udev, usb_sndintpipe(udev, EP_REGS_OUT),
1911                               req, req_len, &actual_req_len, 50 /* ms */);
1912         if (r) {
1913                 dev_dbg_f(zd_usb_dev(usb),
1914                         "error in usb_interrupt_msg(). Error number %d\n", r);
1915                 goto out;
1916         }
1917         if (req_len != actual_req_len) {
1918                 dev_dbg_f(zd_usb_dev(usb), "error in usb_interrupt_msg()"
1919                         " req_len %d != actual_req_len %d\n",
1920                         req_len, actual_req_len);
1921                 r = -EIO;
1922                 goto out;
1923         }
1924
1925         /* FALL-THROUGH with r == 0 */
1926 out:
1927         return r;
1928 }