drivers/net/wireless/zd1211rw/zd_usb.c

   1 /* zd_usb.c
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/init.h>
  20 #include <linux/module.h>
  21 #include <linux/firmware.h>
  22 #include <linux/device.h>
  23 #include <linux/errno.h>
  24 #include <linux/skbuff.h>
  25 #include <linux/usb.h>
  26 #include <linux/workqueue.h>
  27 #include <net/ieee80211.h>
  28 #include <asm/unaligned.h>
  29
  30 #include "zd_def.h"
  31 #include "zd_netdev.h"
  32 #include "zd_mac.h"
  33 #include "zd_usb.h"
  34 #include "zd_util.h"
  35
  36 static struct usb_device_id usb_ids[] = {
  37         /* ZD1211 */
  38         { USB_DEVICE(0x0ace, 0x1211), .driver_info = DEVICE_ZD1211 },
  39         { USB_DEVICE(0x07b8, 0x6001), .driver_info = DEVICE_ZD1211 },
  40         { USB_DEVICE(0x126f, 0xa006), .driver_info = DEVICE_ZD1211 },
  41         { USB_DEVICE(0x6891, 0xa727), .driver_info = DEVICE_ZD1211 },
  42         { USB_DEVICE(0x0df6, 0x9071), .driver_info = DEVICE_ZD1211 },
  43         { USB_DEVICE(0x0df6, 0x9075), .driver_info = DEVICE_ZD1211 },
  44         { USB_DEVICE(0x157e, 0x300b), .driver_info = DEVICE_ZD1211 },
  45         { USB_DEVICE(0x079b, 0x004a), .driver_info = DEVICE_ZD1211 },
  46         { USB_DEVICE(0x1740, 0x2000), .driver_info = DEVICE_ZD1211 },
  47         { USB_DEVICE(0x157e, 0x3204), .driver_info = DEVICE_ZD1211 },
  48         { USB_DEVICE(0x0586, 0x3402), .driver_info = DEVICE_ZD1211 },
  49         { USB_DEVICE(0x0b3b, 0x5630), .driver_info = DEVICE_ZD1211 },
  50         { USB_DEVICE(0x0b05, 0x170c), .driver_info = DEVICE_ZD1211 },
  51         { USB_DEVICE(0x1435, 0x0711), .driver_info = DEVICE_ZD1211 },
  52         { USB_DEVICE(0x0586, 0x3409), .driver_info = DEVICE_ZD1211 },
  53         { USB_DEVICE(0x0b3b, 0x1630), .driver_info = DEVICE_ZD1211 },
  54         { USB_DEVICE(0x0586, 0x3401), .driver_info = DEVICE_ZD1211 },
  55         { USB_DEVICE(0x14ea, 0xab13), .driver_info = DEVICE_ZD1211 },
  56         { USB_DEVICE(0x13b1, 0x001e), .driver_info = DEVICE_ZD1211 },
  57         { USB_DEVICE(0x0586, 0x3407), .driver_info = DEVICE_ZD1211 },
  58         /* ZD1211B */
  59         { USB_DEVICE(0x0ace, 0x1215), .driver_info = DEVICE_ZD1211B },
  60         { USB_DEVICE(0x157e, 0x300d), .driver_info = DEVICE_ZD1211B },
  61         { USB_DEVICE(0x079b, 0x0062), .driver_info = DEVICE_ZD1211B },
  62         { USB_DEVICE(0x1582, 0x6003), .driver_info = DEVICE_ZD1211B },
  63         { USB_DEVICE(0x050d, 0x705c), .driver_info = DEVICE_ZD1211B },
  64         { USB_DEVICE(0x083a, 0x4505), .driver_info = DEVICE_ZD1211B },
  65         { USB_DEVICE(0x0471, 0x1236), .driver_info = DEVICE_ZD1211B },
  66         { USB_DEVICE(0x13b1, 0x0024), .driver_info = DEVICE_ZD1211B },
  67         { USB_DEVICE(0x0586, 0x340f), .driver_info = DEVICE_ZD1211B },
  68         { USB_DEVICE(0x0b05, 0x171b), .driver_info = DEVICE_ZD1211B },
  69         { USB_DEVICE(0x0586, 0x3410), .driver_info = DEVICE_ZD1211B },
  70         { USB_DEVICE(0x0baf, 0x0121), .driver_info = DEVICE_ZD1211B },
  71         { USB_DEVICE(0x0586, 0x3412), .driver_info = DEVICE_ZD1211B },
  72         { USB_DEVICE(0x0586, 0x3413), .driver_info = DEVICE_ZD1211B },
  73         { USB_DEVICE(0x0053, 0x5301), .driver_info = DEVICE_ZD1211B },
  74         { USB_DEVICE(0x0411, 0x00da), .driver_info = DEVICE_ZD1211B },
  75         { USB_DEVICE(0x2019, 0x5303), .driver_info = DEVICE_ZD1211B },
  76         { USB_DEVICE(0x129b, 0x1667), .driver_info = DEVICE_ZD1211B },
  77         { USB_DEVICE(0x0cde, 0x001a), .driver_info = DEVICE_ZD1211B },
  78         { USB_DEVICE(0x0586, 0x340a), .driver_info = DEVICE_ZD1211B },
  79         /* "Driverless" devices that need ejecting */
  80         { USB_DEVICE(0x0ace, 0x2011), .driver_info = DEVICE_INSTALLER },
  81         { USB_DEVICE(0x0ace, 0x20ff), .driver_info = DEVICE_INSTALLER },
  82         {}
  83 };
  84
  85 MODULE_LICENSE("GPL");
  86 MODULE_DESCRIPTION("USB driver for devices with the ZD1211 chip.");
  87 MODULE_AUTHOR("Ulrich Kunitz");
  88 MODULE_AUTHOR("Daniel Drake");
  89 MODULE_VERSION("1.0");
  90 MODULE_DEVICE_TABLE(usb, usb_ids);
  91
  92 #define FW_ZD1211_PREFIX        "zd1211/zd1211_"
  93 #define FW_ZD1211B_PREFIX       "zd1211/zd1211b_"
  94
  95 /* USB device initialization */
  96
  97 static int request_fw_file(
  98         const struct firmware **fw, const char *name, struct device *device)
  99 {
 100         int r;
 101
 102         dev_dbg_f(device, "fw name %s\n", name);
 103
 104         r = request_firmware(fw, name, device);
 105         if (r)
 106                 dev_err(device,
 107                        "Could not load firmware file %s. Error number %d\n",
 108                        name, r);
 109         return r;
 110 }
 111
 112 static inline u16 get_bcdDevice(const struct usb_device *udev)
 113 {
 114         return le16_to_cpu(udev->descriptor.bcdDevice);
 115 }
 116
 117 enum upload_code_flags {
 118         REBOOT = 1,
 119 };
 120
 121 /* Ensures that MAX_TRANSFER_SIZE is even. */
 122 #define MAX_TRANSFER_SIZE (USB_MAX_TRANSFER_SIZE & ~1)
 123
 124 static int upload_code(struct usb_device *udev,
 125         const u8 *data, size_t size, u16 code_offset, int flags)
 126 {
 127         u8 *p;
 128         int r;
 129
 130         /* USB request blocks need "kmalloced" buffers.
 131          */
 132         p = kmalloc(MAX_TRANSFER_SIZE, GFP_KERNEL);
 133         if (!p) {
 134                 dev_err(&udev->dev, "out of memory\n");
 135                 r = -ENOMEM;
 136                 goto error;
 137         }
 138
 139         size &= ~1;
 140         while (size > 0) {
 141                 size_t transfer_size = size <= MAX_TRANSFER_SIZE ?
 142                         size : MAX_TRANSFER_SIZE;
 143
 144                 dev_dbg_f(&udev->dev, "transfer size %zu\n", transfer_size);
 145
 146                 memcpy(p, data, transfer_size);
 147                 r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 148                         USB_REQ_FIRMWARE_DOWNLOAD,
 149                         USB_DIR_OUT | USB_TYPE_VENDOR,
 150                         code_offset, 0, p, transfer_size, 1000 /* ms */);
 151                 if (r < 0) {
 152                         dev_err(&udev->dev,
 153                                "USB control request for firmware upload"
 154                                " failed. Error number %d\n", r);
 155                         goto error;
 156                 }
 157                 transfer_size = r & ~1;
 158
 159                 size -= transfer_size;
 160                 data += transfer_size;
 161                 code_offset += transfer_size/sizeof(u16);
 162         }
 163
 164         if (flags & REBOOT) {
 165                 u8 ret;
 166
 167                 r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 168                         USB_REQ_FIRMWARE_CONFIRM,
 169                         USB_DIR_IN | USB_TYPE_VENDOR,
 170                         0, 0, &ret, sizeof(ret), 5000 /* ms */);
 171                 if (r != sizeof(ret)) {
 172                         dev_err(&udev->dev,
 173                                 "control request firmeware confirmation failed."
 174                                 " Return value %d\n", r);
 175                         if (r >= 0)
 176                                 r = -ENODEV;
 177                         goto error;
 178                 }
 179                 if (ret & 0x80) {
 180                         dev_err(&udev->dev,
 181                                 "Internal error while downloading."
 182                                 " Firmware confirm return value %#04x\n",
 183                                 (unsigned int)ret);
 184                         r = -ENODEV;
 185                         goto error;
 186                 }
 187                 dev_dbg_f(&udev->dev, "firmware confirm return value %#04x\n",
 188                         (unsigned int)ret);
 189         }
 190
 191         r = 0;
 192 error:
 193         kfree(p);
 194         return r;
 195 }
 196
 197 static u16 get_word(const void *data, u16 offset)
 198 {
 199         const __le16 *p = data;
 200         return le16_to_cpu(p[offset]);
 201 }
 202
 203 static char *get_fw_name(struct zd_usb *usb, char *buffer, size_t size,
 204                        const char* postfix)
 205 {
 206         scnprintf(buffer, size, "%s%s",
 207                 usb->is_zd1211b ?
 208                         FW_ZD1211B_PREFIX : FW_ZD1211_PREFIX,
 209                 postfix);
 210         return buffer;
 211 }
 212
 213 static int handle_version_mismatch(struct zd_usb *usb,
 214         const struct firmware *ub_fw)
 215 {
 216         struct usb_device *udev = zd_usb_to_usbdev(usb);
 217         const struct firmware *ur_fw = NULL;
 218         int offset;
 219         int r = 0;
 220         char fw_name[128];
 221
 222         r = request_fw_file(&ur_fw,
 223                 get_fw_name(usb, fw_name, sizeof(fw_name), "ur"),
 224                 &udev->dev);
 225         if (r)
 226                 goto error;
 227
 228         r = upload_code(udev, ur_fw->data, ur_fw->size, FW_START, REBOOT);
 229         if (r)
 230                 goto error;
 231
 232         offset = (E2P_BOOT_CODE_OFFSET * sizeof(u16));
 233         r = upload_code(udev, ub_fw->data + offset, ub_fw->size - offset,
 234                 E2P_START + E2P_BOOT_CODE_OFFSET, REBOOT);
 235
 236         /* At this point, the vendor driver downloads the whole firmware
 237          * image, hacks around with version IDs, and uploads it again,
 238          * completely overwriting the boot code. We do not do this here as
 239          * it is not required on any tested devices, and it is suspected to
 240          * cause problems. */
 241 error:
 242         release_firmware(ur_fw);
 243         return r;
 244 }
 245
 246 static int upload_firmware(struct zd_usb *usb)
 247 {
 248         int r;
 249         u16 fw_bcdDevice;
 250         u16 bcdDevice;
 251         struct usb_device *udev = zd_usb_to_usbdev(usb);
 252         const struct firmware *ub_fw = NULL;
 253         const struct firmware *uph_fw = NULL;
 254         char fw_name[128];
 255
 256         bcdDevice = get_bcdDevice(udev);
 257
 258         r = request_fw_file(&ub_fw,
 259                 get_fw_name(usb, fw_name, sizeof(fw_name), "ub"),
 260                 &udev->dev);
 261         if (r)
 262                 goto error;
 263
 264         fw_bcdDevice = get_word(ub_fw->data, E2P_DATA_OFFSET);
 265
 266         if (fw_bcdDevice != bcdDevice) {
 267                 dev_info(&udev->dev,
 268                         "firmware version %#06x and device bootcode version "
 269                         "%#06x differ\n", fw_bcdDevice, bcdDevice);
 270                 if (bcdDevice <= 0x4313)
 271                         dev_warn(&udev->dev, "device has old bootcode, please "
 272                                 "report success or failure\n");
 273
 274                 r = handle_version_mismatch(usb, ub_fw);
 275                 if (r)
 276                         goto error;
 277         } else {
 278                 dev_dbg_f(&udev->dev,
 279                         "firmware device id %#06x is equal to the "
 280                         "actual device id\n", fw_bcdDevice);
 281         }
 282
 283
 284         r = request_fw_file(&uph_fw,
 285                 get_fw_name(usb, fw_name, sizeof(fw_name), "uphr"),
 286                 &udev->dev);
 287         if (r)
 288                 goto error;
 289
 290         r = upload_code(udev, uph_fw->data, uph_fw->size, FW_START, REBOOT);
 291         if (r) {
 292                 dev_err(&udev->dev,
 293                         "Could not upload firmware code uph. Error number %d\n",
 294                         r);
 295         }
 296
 297         /* FALL-THROUGH */
 298 error:
 299         release_firmware(ub_fw);
 300         release_firmware(uph_fw);
 301         return r;
 302 }
 303
 304 /* Read data from device address space using "firmware interface" which does
 305  * not require firmware to be loaded. */
 306 int zd_usb_read_fw(struct zd_usb *usb, zd_addr_t addr, u8 *data, u16 len)
 307 {
 308         int r;
 309         struct usb_device *udev = zd_usb_to_usbdev(usb);
 310
 311         r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 312                 USB_REQ_FIRMWARE_READ_DATA, USB_DIR_IN | 0x40, addr, 0,
 313                 data, len, 5000);
 314         if (r < 0) {
 315                 dev_err(&udev->dev,
 316                         "read over firmware interface failed: %d\n", r);
 317                 return r;
 318         } else if (r != len) {
 319                 dev_err(&udev->dev,
 320                         "incomplete read over firmware interface: %d/%d\n",
 321                         r, len);
 322                 return -EIO;
 323         }
 324
 325         return 0;
 326 }
 327
 328 #define urb_dev(urb) (&(urb)->dev->dev)
 329
 330 static inline void handle_regs_int(struct urb *urb)
 331 {
 332         struct zd_usb *usb = urb->context;
 333         struct zd_usb_interrupt *intr = &usb->intr;
 334         int len;
 335
 336         ZD_ASSERT(in_interrupt());
 337         spin_lock(&intr->lock);
 338
 339         if (intr->read_regs_enabled) {
 340                 intr->read_regs.length = len = urb->actual_length;
 341
 342                 if (len > sizeof(intr->read_regs.buffer))
 343                         len = sizeof(intr->read_regs.buffer);
 344                 memcpy(intr->read_regs.buffer, urb->transfer_buffer, len);
 345                 intr->read_regs_enabled = 0;
 346                 complete(&intr->read_regs.completion);
 347                 goto out;
 348         }
 349
 350         dev_dbg_f(urb_dev(urb), "regs interrupt ignored\n");
 351 out:
 352         spin_unlock(&intr->lock);
 353 }
 354
 355 static inline void handle_retry_failed_int(struct urb *urb)
 356 {
 357         struct zd_usb *usb = urb->context;
 358         struct zd_mac *mac = zd_usb_to_mac(usb);
 359         struct ieee80211_device *ieee = zd_mac_to_ieee80211(mac);
 360
 361         ieee->stats.tx_errors++;
 362         ieee->ieee_stats.tx_retry_limit_exceeded++;
 363         dev_dbg_f(urb_dev(urb), "retry failed interrupt\n");
 364 }
 365
 366
 367 static void int_urb_complete(struct urb *urb)
 368 {
 369         int r;
 370         struct usb_int_header *hdr;
 371
 372         switch (urb->status) {
 373         case 0:
 374                 break;
 375         case -ESHUTDOWN:
 376         case -EINVAL:
 377         case -ENODEV:
 378         case -ENOENT:
 379         case -ECONNRESET:
 380         case -EPIPE:
 381                 goto kfree;
 382         default:
 383                 goto resubmit;
 384         }
 385
 386         if (urb->actual_length < sizeof(hdr)) {
 387                 dev_dbg_f(urb_dev(urb), "error: urb %p to small\n", urb);
 388                 goto resubmit;
 389         }
 390
 391         hdr = urb->transfer_buffer;
 392         if (hdr->type != USB_INT_TYPE) {
 393                 dev_dbg_f(urb_dev(urb), "error: urb %p wrong type\n", urb);
 394                 goto resubmit;
 395         }
 396
 397         switch (hdr->id) {
 398         case USB_INT_ID_REGS:
 399                 handle_regs_int(urb);
 400                 break;
 401         case USB_INT_ID_RETRY_FAILED:
 402                 handle_retry_failed_int(urb);
 403                 break;
 404         default:
 405                 dev_dbg_f(urb_dev(urb), "error: urb %p unknown id %x\n", urb,
 406                         (unsigned int)hdr->id);
 407                 goto resubmit;
 408         }
 409
 410 resubmit:
 411         r = usb_submit_urb(urb, GFP_ATOMIC);
 412         if (r) {
 413                 dev_dbg_f(urb_dev(urb), "resubmit urb %p\n", urb);
 414                 goto kfree;
 415         }
 416         return;
 417 kfree:
 418         kfree(urb->transfer_buffer);
 419 }
 420
 421 static inline int int_urb_interval(struct usb_device *udev)
 422 {
 423         switch (udev->speed) {
 424         case USB_SPEED_HIGH:
 425                 return 4;
 426         case USB_SPEED_LOW:
 427                 return 10;
 428         case USB_SPEED_FULL:
 429         default:
 430                 return 1;
 431         }
 432 }
 433
 434 static inline int usb_int_enabled(struct zd_usb *usb)
 435 {
 436         unsigned long flags;
 437         struct zd_usb_interrupt *intr = &usb->intr;
 438         struct urb *urb;
 439
 440         spin_lock_irqsave(&intr->lock, flags);
 441         urb = intr->urb;
 442         spin_unlock_irqrestore(&intr->lock, flags);
 443         return urb != NULL;
 444 }
 445
 446 int zd_usb_enable_int(struct zd_usb *usb)
 447 {
 448         int r;
 449         struct usb_device *udev;
 450         struct zd_usb_interrupt *intr = &usb->intr;
 451         void *transfer_buffer = NULL;
 452         struct urb *urb;
 453
 454         dev_dbg_f(zd_usb_dev(usb), "\n");
 455
 456         urb = usb_alloc_urb(0, GFP_KERNEL);
 457         if (!urb) {
 458                 r = -ENOMEM;
 459                 goto out;
 460         }
 461
 462         ZD_ASSERT(!irqs_disabled());
 463         spin_lock_irq(&intr->lock);
 464         if (intr->urb) {
 465                 spin_unlock_irq(&intr->lock);
 466                 r = 0;
 467                 goto error_free_urb;
 468         }
 469         intr->urb = urb;
 470         spin_unlock_irq(&intr->lock);
 471
 472         /* TODO: make it a DMA buffer */
 473         r = -ENOMEM;
 474         transfer_buffer = kmalloc(USB_MAX_EP_INT_BUFFER, GFP_KERNEL);
 475         if (!transfer_buffer) {
 476                 dev_dbg_f(zd_usb_dev(usb),
 477                         "couldn't allocate transfer_buffer\n");
 478                 goto error_set_urb_null;
 479         }
 480
 481         udev = zd_usb_to_usbdev(usb);
 482         usb_fill_int_urb(urb, udev, usb_rcvintpipe(udev, EP_INT_IN),
 483                          transfer_buffer, USB_MAX_EP_INT_BUFFER,
 484                          int_urb_complete, usb,
 485                          intr->interval);
 486
 487         dev_dbg_f(zd_usb_dev(usb), "submit urb %p\n", intr->urb);
 488         r = usb_submit_urb(urb, GFP_KERNEL);
 489         if (r) {
 490                 dev_dbg_f(zd_usb_dev(usb),
 491                          "Couldn't submit urb. Error number %d\n", r);
 492                 goto error;
 493         }
 494
 495         return 0;
 496 error:
 497         kfree(transfer_buffer);
 498 error_set_urb_null:
 499         spin_lock_irq(&intr->lock);
 500         intr->urb = NULL;
 501         spin_unlock_irq(&intr->lock);
 502 error_free_urb:
 503         usb_free_urb(urb);
 504 out:
 505         return r;
 506 }
 507
 508 void zd_usb_disable_int(struct zd_usb *usb)
 509 {
 510         unsigned long flags;
 511         struct zd_usb_interrupt *intr = &usb->intr;
 512         struct urb *urb;
 513
 514         spin_lock_irqsave(&intr->lock, flags);
 515         urb = intr->urb;
 516         if (!urb) {
 517                 spin_unlock_irqrestore(&intr->lock, flags);
 518                 return;
 519         }
 520         intr->urb = NULL;
 521         spin_unlock_irqrestore(&intr->lock, flags);
 522
 523         usb_kill_urb(urb);
 524         dev_dbg_f(zd_usb_dev(usb), "urb %p killed\n", urb);
 525         usb_free_urb(urb);
 526 }
 527
 528 static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
 529                              unsigned int length)
 530 {
 531         int i;
 532         struct zd_mac *mac = zd_usb_to_mac(usb);
 533         const struct rx_length_info *length_info;
 534
 535         if (length < sizeof(struct rx_length_info)) {
 536                 /* It's not a complete packet anyhow. */
 537                 struct ieee80211_device *ieee = zd_mac_to_ieee80211(mac);
 538                 ieee->stats.rx_errors++;
 539                 ieee->stats.rx_length_errors++;
 540                 return;
 541         }
 542         length_info = (struct rx_length_info *)
 543                 (buffer + length - sizeof(struct rx_length_info));
 544
 545         /* It might be that three frames are merged into a single URB
 546          * transaction. We have to check for the length info tag.
 547          *
 548          * While testing we discovered that length_info might be unaligned,
 549          * because if USB transactions are merged, the last packet will not
 550          * be padded. Unaligned access might also happen if the length_info
 551          * structure is not present.
 552          */
 553         if (get_unaligned(&length_info->tag) == cpu_to_le16(RX_LENGTH_INFO_TAG))
 554         {
 555                 unsigned int l, k, n;
 556                 for (i = 0, l = 0;; i++) {
 557                         k = le16_to_cpu(get_unaligned(&length_info->length[i]));
 558                         if (k == 0)
 559                                 return;
 560                         n = l+k;
 561                         if (n > length)
 562                                 return;
 563                         zd_mac_rx_irq(mac, buffer+l, k);
 564                         if (i >= 2)
 565                                 return;
 566                         l = (n+3) & ~3;
 567                 }
 568         } else {
 569                 zd_mac_rx_irq(mac, buffer, length);
 570         }
 571 }
 572
 573 static void rx_urb_complete(struct urb *urb)
 574 {
 575         struct zd_usb *usb;
 576         struct zd_usb_rx *rx;
 577         const u8 *buffer;
 578         unsigned int length;
 579
 580         switch (urb->status) {
 581         case 0:
 582                 break;
 583         case -ESHUTDOWN:
 584         case -EINVAL:
 585         case -ENODEV:
 586         case -ENOENT:
 587         case -ECONNRESET:
 588         case -EPIPE:
 589                 return;
 590         default:
 591                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 592                 goto resubmit;
 593         }
 594
 595         buffer = urb->transfer_buffer;
 596         length = urb->actual_length;
 597         usb = urb->context;
 598         rx = &usb->rx;
 599
 600         if (length%rx->usb_packet_size > rx->usb_packet_size-4) {
 601                 /* If there is an old first fragment, we don't care. */
 602                 dev_dbg_f(urb_dev(urb), "*** first fragment ***\n");
 603                 ZD_ASSERT(length <= ARRAY_SIZE(rx->fragment));
 604                 spin_lock(&rx->lock);
 605                 memcpy(rx->fragment, buffer, length);
 606                 rx->fragment_length = length;
 607                 spin_unlock(&rx->lock);
 608                 goto resubmit;
 609         }
 610
 611         spin_lock(&rx->lock);
 612         if (rx->fragment_length > 0) {
 613                 /* We are on a second fragment, we believe */
 614                 ZD_ASSERT(length + rx->fragment_length <=
 615                           ARRAY_SIZE(rx->fragment));
 616                 dev_dbg_f(urb_dev(urb), "*** second fragment ***\n");
 617                 memcpy(rx->fragment+rx->fragment_length, buffer, length);
 618                 handle_rx_packet(usb, rx->fragment,
 619                                  rx->fragment_length + length);
 620                 rx->fragment_length = 0;
 621                 spin_unlock(&rx->lock);
 622         } else {
 623                 spin_unlock(&rx->lock);
 624                 handle_rx_packet(usb, buffer, length);
 625         }
 626
 627 resubmit:
 628         usb_submit_urb(urb, GFP_ATOMIC);
 629 }
 630
 631 static struct urb *alloc_urb(struct zd_usb *usb)
 632 {
 633         struct usb_device *udev = zd_usb_to_usbdev(usb);
 634         struct urb *urb;
 635         void *buffer;
 636
 637         urb = usb_alloc_urb(0, GFP_KERNEL);
 638         if (!urb)
 639                 return NULL;
 640         buffer = usb_buffer_alloc(udev, USB_MAX_RX_SIZE, GFP_KERNEL,
 641                                   &urb->transfer_dma);
 642         if (!buffer) {
 643                 usb_free_urb(urb);
 644                 return NULL;
 645         }
 646
 647         usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, EP_DATA_IN),
 648                           buffer, USB_MAX_RX_SIZE,
 649                           rx_urb_complete, usb);
 650         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 651
 652         return urb;
 653 }
 654
 655 static void free_urb(struct urb *urb)
 656 {
 657         if (!urb)
 658                 return;
 659         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 660                         urb->transfer_buffer, urb->transfer_dma);
 661         usb_free_urb(urb);
 662 }
 663
 664 int zd_usb_enable_rx(struct zd_usb *usb)
 665 {
 666         int i, r;
 667         struct zd_usb_rx *rx = &usb->rx;
 668         struct urb **urbs;
 669
 670         dev_dbg_f(zd_usb_dev(usb), "\n");
 671
 672         r = -ENOMEM;
 673         urbs = kcalloc(URBS_COUNT, sizeof(struct urb *), GFP_KERNEL);
 674         if (!urbs)
 675                 goto error;
 676         for (i = 0; i < URBS_COUNT; i++) {
 677                 urbs[i] = alloc_urb(usb);
 678                 if (!urbs[i])
 679                         goto error;
 680         }
 681
 682         ZD_ASSERT(!irqs_disabled());
 683         spin_lock_irq(&rx->lock);
 684         if (rx->urbs) {
 685                 spin_unlock_irq(&rx->lock);
 686                 r = 0;
 687                 goto error;
 688         }
 689         rx->urbs = urbs;
 690         rx->urbs_count = URBS_COUNT;
 691         spin_unlock_irq(&rx->lock);
 692
 693         for (i = 0; i < URBS_COUNT; i++) {
 694                 r = usb_submit_urb(urbs[i], GFP_KERNEL);
 695                 if (r)
 696                         goto error_submit;
 697         }
 698
 699         return 0;
 700 error_submit:
 701         for (i = 0; i < URBS_COUNT; i++) {
 702                 usb_kill_urb(urbs[i]);
 703         }
 704         spin_lock_irq(&rx->lock);
 705         rx->urbs = NULL;
 706         rx->urbs_count = 0;
 707         spin_unlock_irq(&rx->lock);
 708 error:
 709         if (urbs) {
 710                 for (i = 0; i < URBS_COUNT; i++)
 711                         free_urb(urbs[i]);
 712         }
 713         return r;
 714 }
 715
 716 void zd_usb_disable_rx(struct zd_usb *usb)
 717 {
 718         int i;
 719         unsigned long flags;
 720         struct urb **urbs;
 721         unsigned int count;
 722         struct zd_usb_rx *rx = &usb->rx;
 723
 724         spin_lock_irqsave(&rx->lock, flags);
 725         urbs = rx->urbs;
 726         count = rx->urbs_count;
 727         spin_unlock_irqrestore(&rx->lock, flags);
 728         if (!urbs)
 729                 return;
 730
 731         for (i = 0; i < count; i++) {
 732                 usb_kill_urb(urbs[i]);
 733                 free_urb(urbs[i]);
 734         }
 735         kfree(urbs);
 736
 737         spin_lock_irqsave(&rx->lock, flags);
 738         rx->urbs = NULL;
 739         rx->urbs_count = 0;
 740         spin_unlock_irqrestore(&rx->lock, flags);
 741 }
 742
 743 static void tx_urb_complete(struct urb *urb)
 744 {
 745         int r;
 746
 747         switch (urb->status) {
 748         case 0:
 749                 break;
 750         case -ESHUTDOWN:
 751         case -EINVAL:
 752         case -ENODEV:
 753         case -ENOENT:
 754         case -ECONNRESET:
 755         case -EPIPE:
 756                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 757                 break;
 758         default:
 759                 dev_dbg_f(urb_dev(urb), "urb %p error %d\n", urb, urb->status);
 760                 goto resubmit;
 761         }
 762 free_urb:
 763         usb_buffer_free(urb->dev, urb->transfer_buffer_length,
 764                         urb->transfer_buffer, urb->transfer_dma);
 765         usb_free_urb(urb);
 766         return;
 767 resubmit:
 768         r = usb_submit_urb(urb, GFP_ATOMIC);
 769         if (r) {
 770                 dev_dbg_f(urb_dev(urb), "error resubmit urb %p %d\n", urb, r);
 771                 goto free_urb;
 772         }
 773 }
 774
 775 /* Puts the frame on the USB endpoint. It doesn't wait for
 776  * completion. The frame must contain the control set.
 777  */
 778 int zd_usb_tx(struct zd_usb *usb, const u8 *frame, unsigned int length)
 779 {
 780         int r;
 781         struct usb_device *udev = zd_usb_to_usbdev(usb);
 782         struct urb *urb;
 783         void *buffer;
 784
 785         urb = usb_alloc_urb(0, GFP_ATOMIC);
 786         if (!urb) {
 787                 r = -ENOMEM;
 788                 goto out;
 789         }
 790
 791         buffer = usb_buffer_alloc(zd_usb_to_usbdev(usb), length, GFP_ATOMIC,
 792                                   &urb->transfer_dma);
 793         if (!buffer) {
 794                 r = -ENOMEM;
 795                 goto error_free_urb;
 796         }
 797         memcpy(buffer, frame, length);
 798
 799         usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, EP_DATA_OUT),
 800                           buffer, length, tx_urb_complete, NULL);
 801         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 802
 803         r = usb_submit_urb(urb, GFP_ATOMIC);
 804         if (r)
 805                 goto error;
 806         return 0;
 807 error:
 808         usb_buffer_free(zd_usb_to_usbdev(usb), length, buffer,
 809                         urb->transfer_dma);
 810 error_free_urb:
 811         usb_free_urb(urb);
 812 out:
 813         return r;
 814 }
 815
 816 static inline void init_usb_interrupt(struct zd_usb *usb)
 817 {
 818         struct zd_usb_interrupt *intr = &usb->intr;
 819
 820         spin_lock_init(&intr->lock);
 821         intr->interval = int_urb_interval(zd_usb_to_usbdev(usb));
 822         init_completion(&intr->read_regs.completion);
 823         intr->read_regs.cr_int_addr = cpu_to_le16((u16)CR_INTERRUPT);
 824 }
 825
 826 static inline void init_usb_rx(struct zd_usb *usb)
 827 {
 828         struct zd_usb_rx *rx = &usb->rx;
 829         spin_lock_init(&rx->lock);
 830         if (interface_to_usbdev(usb->intf)->speed == USB_SPEED_HIGH) {
 831                 rx->usb_packet_size = 512;
 832         } else {
 833                 rx->usb_packet_size = 64;
 834         }
 835         ZD_ASSERT(rx->fragment_length == 0);
 836 }
 837
 838 static inline void init_usb_tx(struct zd_usb *usb)
 839 {
 840         /* FIXME: at this point we will allocate a fixed number of urb's for
 841          * use in a cyclic scheme */
 842 }
 843
 844 void zd_usb_init(struct zd_usb *usb, struct net_device *netdev,
 845                  struct usb_interface *intf)
 846 {
 847         memset(usb, 0, sizeof(*usb));
 848         usb->intf = usb_get_intf(intf);
 849         usb_set_intfdata(usb->intf, netdev);
 850         init_usb_interrupt(usb);
 851         init_usb_tx(usb);
 852         init_usb_rx(usb);
 853 }
 854
 855 void zd_usb_clear(struct zd_usb *usb)
 856 {
 857         usb_set_intfdata(usb->intf, NULL);
 858         usb_put_intf(usb->intf);
 859         ZD_MEMCLEAR(usb, sizeof(*usb));
 860         /* FIXME: usb_interrupt, usb_tx, usb_rx? */
 861 }
 862
 863 static const char *speed(enum usb_device_speed speed)
 864 {
 865         switch (speed) {
 866         case USB_SPEED_LOW:
 867                 return "low";
 868         case USB_SPEED_FULL:
 869                 return "full";
 870         case USB_SPEED_HIGH:
 871                 return "high";
 872         default:
 873                 return "unknown speed";
 874         }
 875 }
 876
 877 static int scnprint_id(struct usb_device *udev, char *buffer, size_t size)
 878 {
 879         return scnprintf(buffer, size, "%04hx:%04hx v%04hx %s",
 880                 le16_to_cpu(udev->descriptor.idVendor),
 881                 le16_to_cpu(udev->descriptor.idProduct),
 882                 get_bcdDevice(udev),
 883                 speed(udev->speed));
 884 }
 885
 886 int zd_usb_scnprint_id(struct zd_usb *usb, char *buffer, size_t size)
 887 {
 888         struct usb_device *udev = interface_to_usbdev(usb->intf);
 889         return scnprint_id(udev, buffer, size);
 890 }
 891
 892 #ifdef DEBUG
 893 static void print_id(struct usb_device *udev)
 894 {
 895         char buffer[40];
 896
 897         scnprint_id(udev, buffer, sizeof(buffer));
 898         buffer[sizeof(buffer)-1] = 0;
 899         dev_dbg_f(&udev->dev, "%s\n", buffer);
 900 }
 901 #else
 902 #define print_id(udev) do { } while (0)
 903 #endif
 904
 905 static int eject_installer(struct usb_interface *intf)
 906 {
 907         struct usb_device *udev = interface_to_usbdev(intf);
 908         struct usb_host_interface *iface_desc = &intf->altsetting[0];
 909         struct usb_endpoint_descriptor *endpoint;
 910         unsigned char *cmd;
 911         u8 bulk_out_ep;
 912         int r;
 913
 914         /* Find bulk out endpoint */
 915         endpoint = &iface_desc->endpoint[1].desc;
 916         if ((endpoint->bEndpointAddress & USB_TYPE_MASK) == USB_DIR_OUT &&
 917             (endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
 918             USB_ENDPOINT_XFER_BULK) {
 919                 bulk_out_ep = endpoint->bEndpointAddress;
 920         } else {
 921                 dev_err(&udev->dev,
 922                         "zd1211rw: Could not find bulk out endpoint\n");
 923                 return -ENODEV;
 924         }
 925
 926         cmd = kzalloc(31, GFP_KERNEL);
 927         if (cmd == NULL)
 928                 return -ENODEV;
 929
 930         /* USB bulk command block */
 931         cmd[0] = 0x55;  /* bulk command signature */
 932         cmd[1] = 0x53;  /* bulk command signature */
 933         cmd[2] = 0x42;  /* bulk command signature */
 934         cmd[3] = 0x43;  /* bulk command signature */
 935         cmd[14] = 6;    /* command length */
 936
 937         cmd[15] = 0x1b; /* SCSI command: START STOP UNIT */
 938         cmd[19] = 0x2;  /* eject disc */
 939
 940         dev_info(&udev->dev, "Ejecting virtual installer media...\n");
 941         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, bulk_out_ep),
 942                 cmd, 31, NULL, 2000);
 943         kfree(cmd);
 944         if (r)
 945                 return r;
 946
 947         /* At this point, the device disconnects and reconnects with the real
 948          * ID numbers. */
 949
 950         usb_set_intfdata(intf, NULL);
 951         return 0;
 952 }
 953
 954 int zd_usb_init_hw(struct zd_usb *usb)
 955 {
 956         int r;
 957         struct zd_mac *mac = zd_usb_to_mac(usb);
 958
 959         dev_dbg_f(zd_usb_dev(usb), "\n");
 960
 961         r = upload_firmware(usb);
 962         if (r) {
 963                 dev_err(zd_usb_dev(usb),
 964                        "couldn't load firmware. Error number %d\n", r);
 965                 return r;
 966         }
 967
 968         r = usb_reset_configuration(zd_usb_to_usbdev(usb));
 969         if (r) {
 970                 dev_dbg_f(zd_usb_dev(usb),
 971                         "couldn't reset configuration. Error number %d\n", r);
 972                 return r;
 973         }
 974
 975         r = zd_mac_init_hw(mac);
 976         if (r) {
 977                 dev_dbg_f(zd_usb_dev(usb),
 978                          "couldn't initialize mac. Error number %d\n", r);
 979                 return r;
 980         }
 981
 982         usb->initialized = 1;
 983         return 0;
 984 }
 985
 986 static int probe(struct usb_interface *intf, const struct usb_device_id *id)
 987 {
 988         int r;
 989         struct zd_usb *usb;
 990         struct usb_device *udev = interface_to_usbdev(intf);
 991         struct net_device *netdev = NULL;
 992
 993         print_id(udev);
 994
 995         if (id->driver_info & DEVICE_INSTALLER)
 996                 return eject_installer(intf);
 997
 998         switch (udev->speed) {
 999         case USB_SPEED_LOW:
1000         case USB_SPEED_FULL:
1001         case USB_SPEED_HIGH:
1002                 break;
1003         default:
1004                 dev_dbg_f(&intf->dev, "Unknown USB speed\n");
1005                 r = -ENODEV;
1006                 goto error;
1007         }
1008
1009         usb_reset_device(interface_to_usbdev(intf));
1010
1011         netdev = zd_netdev_alloc(intf);
1012         if (netdev == NULL) {
1013                 r = -ENOMEM;
1014                 goto error;
1015         }
1016
1017         usb = &zd_netdev_mac(netdev)->chip.usb;
1018         usb->is_zd1211b = (id->driver_info == DEVICE_ZD1211B) != 0;
1019
1020         r = zd_mac_preinit_hw(zd_netdev_mac(netdev));
1021         if (r) {
1022                 dev_dbg_f(&intf->dev,
1023                          "couldn't initialize mac. Error number %d\n", r);
1024                 goto error;
1025         }
1026
1027         r = register_netdev(netdev);
1028         if (r) {
1029                 dev_dbg_f(&intf->dev,
1030                          "couldn't register netdev. Error number %d\n", r);
1031                 goto error;
1032         }
1033
1034         dev_dbg_f(&intf->dev, "successful\n");
1035         dev_info(&intf->dev,"%s\n", netdev->name);
1036         return 0;
1037 error:
1038         usb_reset_device(interface_to_usbdev(intf));
1039         zd_netdev_free(netdev);
1040         return r;
1041 }
1042
1043 static void disconnect(struct usb_interface *intf)
1044 {
1045         struct net_device *netdev = zd_intf_to_netdev(intf);
1046         struct zd_mac *mac = zd_netdev_mac(netdev);
1047         struct zd_usb *usb = &mac->chip.usb;
1048
1049         /* Either something really bad happened, or we're just dealing with
1050          * a DEVICE_INSTALLER. */
1051         if (netdev == NULL)
1052                 return;
1053
1054         dev_dbg_f(zd_usb_dev(usb), "\n");
1055
1056         zd_netdev_disconnect(netdev);
1057
1058         /* Just in case something has gone wrong! */
1059         zd_usb_disable_rx(usb);
1060         zd_usb_disable_int(usb);
1061
1062         /* If the disconnect has been caused by a removal of the
1063          * driver module, the reset allows reloading of the driver. If the
1064          * reset will not be executed here, the upload of the firmware in the
1065          * probe function caused by the reloading of the driver will fail.
1066          */
1067         usb_reset_device(interface_to_usbdev(intf));
1068
1069         zd_netdev_free(netdev);
1070         dev_dbg(&intf->dev, "disconnected\n");
1071 }
1072
1073 static struct usb_driver driver = {
1074         .name           = "zd1211rw",
1075         .id_table       = usb_ids,
1076         .probe          = probe,
1077         .disconnect     = disconnect,
1078 };
1079
1080 struct workqueue_struct *zd_workqueue;
1081
1082 static int __init usb_init(void)
1083 {
1084         int r;
1085
1086         pr_debug("%s usb_init()\n", driver.name);
1087
1088         zd_workqueue = create_singlethread_workqueue(driver.name);
1089         if (zd_workqueue == NULL) {
1090                 printk(KERN_ERR "%s couldn't create workqueue\n", driver.name);
1091                 return -ENOMEM;
1092         }
1093
1094         r = usb_register(&driver);
1095         if (r) {
1096                 destroy_workqueue(zd_workqueue);
1097                 printk(KERN_ERR "%s usb_register() failed. Error number %d\n",
1098                        driver.name, r);
1099                 return r;
1100         }
1101
1102         pr_debug("%s initialized\n", driver.name);
1103         return 0;
1104 }
1105
1106 static void __exit usb_exit(void)
1107 {
1108         pr_debug("%s usb_exit()\n", driver.name);
1109         usb_deregister(&driver);
1110         destroy_workqueue(zd_workqueue);
1111 }
1112
1113 module_init(usb_init);
1114 module_exit(usb_exit);
1115
1116 static int usb_int_regs_length(unsigned int count)
1117 {
1118         return sizeof(struct usb_int_regs) + count * sizeof(struct reg_data);
1119 }
1120
1121 static void prepare_read_regs_int(struct zd_usb *usb)
1122 {
1123         struct zd_usb_interrupt *intr = &usb->intr;
1124
1125         spin_lock_irq(&intr->lock);
1126         intr->read_regs_enabled = 1;
1127         INIT_COMPLETION(intr->read_regs.completion);
1128         spin_unlock_irq(&intr->lock);
1129 }
1130
1131 static void disable_read_regs_int(struct zd_usb *usb)
1132 {
1133         struct zd_usb_interrupt *intr = &usb->intr;
1134
1135         spin_lock_irq(&intr->lock);
1136         intr->read_regs_enabled = 0;
1137         spin_unlock_irq(&intr->lock);
1138 }
1139
1140 static int get_results(struct zd_usb *usb, u16 *values,
1141                        struct usb_req_read_regs *req, unsigned int count)
1142 {
1143         int r;
1144         int i;
1145         struct zd_usb_interrupt *intr = &usb->intr;
1146         struct read_regs_int *rr = &intr->read_regs;
1147         struct usb_int_regs *regs = (struct usb_int_regs *)rr->buffer;
1148
1149         spin_lock_irq(&intr->lock);
1150
1151         r = -EIO;
1152         /* The created block size seems to be larger than expected.
1153          * However results appear to be correct.
1154          */
1155         if (rr->length < usb_int_regs_length(count)) {
1156                 dev_dbg_f(zd_usb_dev(usb),
1157                          "error: actual length %d less than expected %d\n",
1158                          rr->length, usb_int_regs_length(count));
1159                 goto error_unlock;
1160         }
1161         if (rr->length > sizeof(rr->buffer)) {
1162                 dev_dbg_f(zd_usb_dev(usb),
1163                          "error: actual length %d exceeds buffer size %zu\n",
1164                          rr->length, sizeof(rr->buffer));
1165                 goto error_unlock;
1166         }
1167
1168         for (i = 0; i < count; i++) {
1169                 struct reg_data *rd = &regs->regs[i];
1170                 if (rd->addr != req->addr[i]) {
1171                         dev_dbg_f(zd_usb_dev(usb),
1172                                  "rd[%d] addr %#06hx expected %#06hx\n", i,
1173                                  le16_to_cpu(rd->addr),
1174                                  le16_to_cpu(req->addr[i]));
1175                         goto error_unlock;
1176                 }
1177                 values[i] = le16_to_cpu(rd->value);
1178         }
1179
1180         r = 0;
1181 error_unlock:
1182         spin_unlock_irq(&intr->lock);
1183         return r;
1184 }
1185
1186 int zd_usb_ioread16v(struct zd_usb *usb, u16 *values,
1187                      const zd_addr_t *addresses, unsigned int count)
1188 {
1189         int r;
1190         int i, req_len, actual_req_len;
1191         struct usb_device *udev;
1192         struct usb_req_read_regs *req = NULL;
1193         unsigned long timeout;
1194
1195         if (count < 1) {
1196                 dev_dbg_f(zd_usb_dev(usb), "error: count is zero\n");
1197                 return -EINVAL;
1198         }
1199         if (count > USB_MAX_IOREAD16_COUNT) {
1200                 dev_dbg_f(zd_usb_dev(usb),
1201                          "error: count %u exceeds possible max %u\n",
1202                          count, USB_MAX_IOREAD16_COUNT);
1203                 return -EINVAL;
1204         }
1205         if (in_atomic()) {
1206                 dev_dbg_f(zd_usb_dev(usb),
1207                          "error: io in atomic context not supported\n");
1208                 return -EWOULDBLOCK;
1209         }
1210         if (!usb_int_enabled(usb)) {
1211                  dev_dbg_f(zd_usb_dev(usb),
1212                           "error: usb interrupt not enabled\n");
1213                 return -EWOULDBLOCK;
1214         }
1215
1216         req_len = sizeof(struct usb_req_read_regs) + count * sizeof(__le16);
1217         req = kmalloc(req_len, GFP_KERNEL);
1218         if (!req)
1219                 return -ENOMEM;
1220         req->id = cpu_to_le16(USB_REQ_READ_REGS);
1221         for (i = 0; i < count; i++)
1222                 req->addr[i] = cpu_to_le16((u16)addresses[i]);
1223
1224         udev = zd_usb_to_usbdev(usb);
1225         prepare_read_regs_int(usb);
1226         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1227                          req, req_len, &actual_req_len, 1000 /* ms */);
1228         if (r) {
1229                 dev_dbg_f(zd_usb_dev(usb),
1230                         "error in usb_bulk_msg(). Error number %d\n", r);
1231                 goto error;
1232         }
1233         if (req_len != actual_req_len) {
1234                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()\n"
1235                         " req_len %d != actual_req_len %d\n",
1236                         req_len, actual_req_len);
1237                 r = -EIO;
1238                 goto error;
1239         }
1240
1241         timeout = wait_for_completion_timeout(&usb->intr.read_regs.completion,
1242                                               msecs_to_jiffies(1000));
1243         if (!timeout) {
1244                 disable_read_regs_int(usb);
1245                 dev_dbg_f(zd_usb_dev(usb), "read timed out\n");
1246                 r = -ETIMEDOUT;
1247                 goto error;
1248         }
1249
1250         r = get_results(usb, values, req, count);
1251 error:
1252         kfree(req);
1253         return r;
1254 }
1255
1256 int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs,
1257                       unsigned int count)
1258 {
1259         int r;
1260         struct usb_device *udev;
1261         struct usb_req_write_regs *req = NULL;
1262         int i, req_len, actual_req_len;
1263
1264         if (count == 0)
1265                 return 0;
1266         if (count > USB_MAX_IOWRITE16_COUNT) {
1267                 dev_dbg_f(zd_usb_dev(usb),
1268                         "error: count %u exceeds possible max %u\n",
1269                         count, USB_MAX_IOWRITE16_COUNT);
1270                 return -EINVAL;
1271         }
1272         if (in_atomic()) {
1273                 dev_dbg_f(zd_usb_dev(usb),
1274                         "error: io in atomic context not supported\n");
1275                 return -EWOULDBLOCK;
1276         }
1277
1278         req_len = sizeof(struct usb_req_write_regs) +
1279                   count * sizeof(struct reg_data);
1280         req = kmalloc(req_len, GFP_KERNEL);
1281         if (!req)
1282                 return -ENOMEM;
1283
1284         req->id = cpu_to_le16(USB_REQ_WRITE_REGS);
1285         for (i = 0; i < count; i++) {
1286                 struct reg_data *rw  = &req->reg_writes[i];
1287                 rw->addr = cpu_to_le16((u16)ioreqs[i].addr);
1288                 rw->value = cpu_to_le16(ioreqs[i].value);
1289         }
1290
1291         udev = zd_usb_to_usbdev(usb);
1292         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1293                          req, req_len, &actual_req_len, 1000 /* ms */);
1294         if (r) {
1295                 dev_dbg_f(zd_usb_dev(usb),
1296                         "error in usb_bulk_msg(). Error number %d\n", r);
1297                 goto error;
1298         }
1299         if (req_len != actual_req_len) {
1300                 dev_dbg_f(zd_usb_dev(usb),
1301                         "error in usb_bulk_msg()"
1302                         " req_len %d != actual_req_len %d\n",
1303                         req_len, actual_req_len);
1304                 r = -EIO;
1305                 goto error;
1306         }
1307
1308         /* FALL-THROUGH with r == 0 */
1309 error:
1310         kfree(req);
1311         return r;
1312 }
1313
1314 int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits)
1315 {
1316         int r;
1317         struct usb_device *udev;
1318         struct usb_req_rfwrite *req = NULL;
1319         int i, req_len, actual_req_len;
1320         u16 bit_value_template;
1321
1322         if (in_atomic()) {
1323                 dev_dbg_f(zd_usb_dev(usb),
1324                         "error: io in atomic context not supported\n");
1325                 return -EWOULDBLOCK;
1326         }
1327         if (bits < USB_MIN_RFWRITE_BIT_COUNT) {
1328                 dev_dbg_f(zd_usb_dev(usb),
1329                         "error: bits %d are smaller than"
1330                         " USB_MIN_RFWRITE_BIT_COUNT %d\n",
1331                         bits, USB_MIN_RFWRITE_BIT_COUNT);
1332                 return -EINVAL;
1333         }
1334         if (bits > USB_MAX_RFWRITE_BIT_COUNT) {
1335                 dev_dbg_f(zd_usb_dev(usb),
1336                         "error: bits %d exceed USB_MAX_RFWRITE_BIT_COUNT %d\n",
1337                         bits, USB_MAX_RFWRITE_BIT_COUNT);
1338                 return -EINVAL;
1339         }
1340 #ifdef DEBUG
1341         if (value & (~0UL << bits)) {
1342                 dev_dbg_f(zd_usb_dev(usb),
1343                         "error: value %#09x has bits >= %d set\n",
1344                         value, bits);
1345                 return -EINVAL;
1346         }
1347 #endif /* DEBUG */
1348
1349         dev_dbg_f(zd_usb_dev(usb), "value %#09x bits %d\n", value, bits);
1350
1351         r = zd_usb_ioread16(usb, &bit_value_template, CR203);
1352         if (r) {
1353                 dev_dbg_f(zd_usb_dev(usb),
1354                         "error %d: Couldn't read CR203\n", r);
1355                 goto out;
1356         }
1357         bit_value_template &= ~(RF_IF_LE|RF_CLK|RF_DATA);
1358
1359         req_len = sizeof(struct usb_req_rfwrite) + bits * sizeof(__le16);
1360         req = kmalloc(req_len, GFP_KERNEL);
1361         if (!req)
1362                 return -ENOMEM;
1363
1364         req->id = cpu_to_le16(USB_REQ_WRITE_RF);
1365         /* 1: 3683a, but not used in ZYDAS driver */
1366         req->value = cpu_to_le16(2);
1367         req->bits = cpu_to_le16(bits);
1368
1369         for (i = 0; i < bits; i++) {
1370                 u16 bv = bit_value_template;
1371                 if (value & (1 << (bits-1-i)))
1372                         bv |= RF_DATA;
1373                 req->bit_values[i] = cpu_to_le16(bv);
1374         }
1375
1376         udev = zd_usb_to_usbdev(usb);
1377         r = usb_bulk_msg(udev, usb_sndbulkpipe(udev, EP_REGS_OUT),
1378                          req, req_len, &actual_req_len, 1000 /* ms */);
1379         if (r) {
1380                 dev_dbg_f(zd_usb_dev(usb),
1381                         "error in usb_bulk_msg(). Error number %d\n", r);
1382                 goto out;
1383         }
1384         if (req_len != actual_req_len) {
1385                 dev_dbg_f(zd_usb_dev(usb), "error in usb_bulk_msg()"
1386                         " req_len %d != actual_req_len %d\n",
1387                         req_len, actual_req_len);
1388                 r = -EIO;
1389                 goto out;
1390         }
1391
1392         /* FALL-THROUGH with r == 0 */
1393 out:
1394         kfree(req);
1395         return r;
1396 }