drivers/usb/atm/usbatm.c

   1 /******************************************************************************
   2  *  usbatm.c - Generic USB xDSL driver core
   3  *
   4  *  Copyright (C) 2001, Alcatel
   5  *  Copyright (C) 2003, Duncan Sands, SolNegro, Josep Comas
   6  *  Copyright (C) 2004, David Woodhouse, Roman Kagan
   7  *
   8  *  This program is free software; you can redistribute it and/or modify it
   9  *  under the terms of the GNU General Public License as published by the Free
  10  *  Software Foundation; either version 2 of the License, or (at your option)
  11  *  any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful, but WITHOUT
  14  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  16  *  more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License along with
  19  *  this program; if not, write to the Free Software Foundation, Inc., 59
  20  *  Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  21  *
  22  ******************************************************************************/
  23
  24 /*
  25  *  Written by Johan Verrept, Duncan Sands (duncan.sands@free.fr) and David Woodhouse
  26  *
  27  *  1.7+:       - See the check-in logs
  28  *
  29  *  1.6:        - No longer opens a connection if the firmware is not loaded
  30  *              - Added support for the speedtouch 330
  31  *              - Removed the limit on the number of devices
  32  *              - Module now autoloads on device plugin
  33  *              - Merged relevant parts of sarlib
  34  *              - Replaced the kernel thread with a tasklet
  35  *              - New packet transmission code
  36  *              - Changed proc file contents
  37  *              - Fixed all known SMP races
  38  *              - Many fixes and cleanups
  39  *              - Various fixes by Oliver Neukum (oliver@neukum.name)
  40  *
  41  *  1.5A:       - Version for inclusion in 2.5 series kernel
  42  *              - Modifications by Richard Purdie (rpurdie@rpsys.net)
  43  *              - made compatible with kernel 2.5.6 onwards by changing
  44  *              usbatm_usb_send_data_context->urb to a pointer and adding code
  45  *              to alloc and free it
  46  *              - remove_wait_queue() added to usbatm_atm_processqueue_thread()
  47  *
  48  *  1.5:        - fixed memory leak when atmsar_decode_aal5 returned NULL.
  49  *              (reported by stephen.robinson@zen.co.uk)
  50  *
  51  *  1.4:        - changed the spin_lock() under interrupt to spin_lock_irqsave()
  52  *              - unlink all active send urbs of a vcc that is being closed.
  53  *
  54  *  1.3.1:      - added the version number
  55  *
  56  *  1.3:        - Added multiple send urb support
  57  *              - fixed memory leak and vcc->tx_inuse starvation bug
  58  *                when not enough memory left in vcc.
  59  *
  60  *  1.2:        - Fixed race condition in usbatm_usb_send_data()
  61  *  1.1:        - Turned off packet debugging
  62  *
  63  */
  64
  65 #include "usbatm.h"
  66
  67 #include <asm/uaccess.h>
  68 #include <linux/crc32.h>
  69 #include <linux/errno.h>
  70 #include <linux/init.h>
  71 #include <linux/interrupt.h>
  72 #include <linux/kernel.h>
  73 #include <linux/module.h>
  74 #include <linux/moduleparam.h>
  75 #include <linux/netdevice.h>
  76 #include <linux/proc_fs.h>
  77 #include <linux/sched.h>
  78 #include <linux/signal.h>
  79 #include <linux/slab.h>
  80 #include <linux/smp_lock.h>
  81 #include <linux/stat.h>
  82 #include <linux/timer.h>
  83 #include <linux/wait.h>
  84
  85 #ifdef VERBOSE_DEBUG
  86 static int usbatm_print_packet(const unsigned char *data, int len);
  87 #define PACKETDEBUG(arg...)     usbatm_print_packet (arg)
  88 #define vdbg(arg...)            dbg (arg)
  89 #else
  90 #define PACKETDEBUG(arg...)
  91 #define vdbg(arg...)
  92 #endif
  93
  94 #define DRIVER_AUTHOR   "Johan Verrept, Duncan Sands <duncan.sands@free.fr>"
  95 #define DRIVER_VERSION  "1.10"
  96 #define DRIVER_DESC     "Generic USB ATM/DSL I/O, version " DRIVER_VERSION
  97
  98 static const char usbatm_driver_name[] = "usbatm";
  99
 100 #define UDSL_MAX_RCV_URBS               16
 101 #define UDSL_MAX_SND_URBS               16
 102 #define UDSL_MAX_BUF_SIZE               65536
 103 #define UDSL_DEFAULT_RCV_URBS           4
 104 #define UDSL_DEFAULT_SND_URBS           4
 105 #define UDSL_DEFAULT_RCV_BUF_SIZE       3392    /* 64 * ATM_CELL_SIZE */
 106 #define UDSL_DEFAULT_SND_BUF_SIZE       3392    /* 64 * ATM_CELL_SIZE */
 107
 108 #define ATM_CELL_HEADER                 (ATM_CELL_SIZE - ATM_CELL_PAYLOAD)
 109
 110 #define THROTTLE_MSECS                  100     /* delay to recover processing after urb submission fails */
 111
 112 static unsigned int num_rcv_urbs = UDSL_DEFAULT_RCV_URBS;
 113 static unsigned int num_snd_urbs = UDSL_DEFAULT_SND_URBS;
 114 static unsigned int rcv_buf_bytes = UDSL_DEFAULT_RCV_BUF_SIZE;
 115 static unsigned int snd_buf_bytes = UDSL_DEFAULT_SND_BUF_SIZE;
 116
 117 module_param(num_rcv_urbs, uint, S_IRUGO);
 118 MODULE_PARM_DESC(num_rcv_urbs,
 119                  "Number of urbs used for reception (range: 0-"
 120                  __MODULE_STRING(UDSL_MAX_RCV_URBS) ", default: "
 121                  __MODULE_STRING(UDSL_DEFAULT_RCV_URBS) ")");
 122
 123 module_param(num_snd_urbs, uint, S_IRUGO);
 124 MODULE_PARM_DESC(num_snd_urbs,
 125                  "Number of urbs used for transmission (range: 0-"
 126                  __MODULE_STRING(UDSL_MAX_SND_URBS) ", default: "
 127                  __MODULE_STRING(UDSL_DEFAULT_SND_URBS) ")");
 128
 129 module_param(rcv_buf_bytes, uint, S_IRUGO);
 130 MODULE_PARM_DESC(rcv_buf_bytes,
 131                  "Size of the buffers used for reception, in bytes (range: 1-"
 132                  __MODULE_STRING(UDSL_MAX_BUF_SIZE) ", default: "
 133                  __MODULE_STRING(UDSL_DEFAULT_RCV_BUF_SIZE) ")");
 134
 135 module_param(snd_buf_bytes, uint, S_IRUGO);
 136 MODULE_PARM_DESC(snd_buf_bytes,
 137                  "Size of the buffers used for transmission, in bytes (range: 1-"
 138                  __MODULE_STRING(UDSL_MAX_BUF_SIZE) ", default: "
 139                  __MODULE_STRING(UDSL_DEFAULT_SND_BUF_SIZE) ")");
 140
 141
 142 /* receive */
 143
 144 struct usbatm_vcc_data {
 145         /* vpi/vci lookup */
 146         struct list_head list;
 147         short vpi;
 148         int vci;
 149         struct atm_vcc *vcc;
 150
 151         /* raw cell reassembly */
 152         struct sk_buff *sarb;
 153 };
 154
 155
 156 /* send */
 157
 158 struct usbatm_control {
 159         struct atm_skb_data atm;
 160         u32 len;
 161         u32 crc;
 162 };
 163
 164 #define UDSL_SKB(x)             ((struct usbatm_control *)(x)->cb)
 165
 166
 167 /* ATM */
 168
 169 static void usbatm_atm_dev_close(struct atm_dev *atm_dev);
 170 static int usbatm_atm_open(struct atm_vcc *vcc);
 171 static void usbatm_atm_close(struct atm_vcc *vcc);
 172 static int usbatm_atm_ioctl(struct atm_dev *atm_dev, unsigned int cmd, void __user * arg);
 173 static int usbatm_atm_send(struct atm_vcc *vcc, struct sk_buff *skb);
 174 static int usbatm_atm_proc_read(struct atm_dev *atm_dev, loff_t * pos, char *page);
 175
 176 static struct atmdev_ops usbatm_atm_devops = {
 177         .dev_close      = usbatm_atm_dev_close,
 178         .open           = usbatm_atm_open,
 179         .close          = usbatm_atm_close,
 180         .ioctl          = usbatm_atm_ioctl,
 181         .send           = usbatm_atm_send,
 182         .proc_read      = usbatm_atm_proc_read,
 183         .owner          = THIS_MODULE,
 184 };
 185
 186
 187 /***********
 188 **  misc  **
 189 ***********/
 190
 191 static inline unsigned int usbatm_pdu_length(unsigned int length)
 192 {
 193         length += ATM_CELL_PAYLOAD - 1 + ATM_AAL5_TRAILER;
 194         return length - length % ATM_CELL_PAYLOAD;
 195 }
 196
 197 static inline void usbatm_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 198 {
 199         if (vcc->pop)
 200                 vcc->pop(vcc, skb);
 201         else
 202                 dev_kfree_skb_any(skb);
 203 }
 204
 205
 206 /***********
 207 **  urbs  **
 208 ************/
 209
 210 static struct urb *usbatm_pop_urb(struct usbatm_channel *channel)
 211 {
 212         struct urb *urb;
 213
 214         spin_lock_irq(&channel->lock);
 215         if (list_empty(&channel->list)) {
 216                 spin_unlock_irq(&channel->lock);
 217                 return NULL;
 218         }
 219
 220         urb = list_entry(channel->list.next, struct urb, urb_list);
 221         list_del(&urb->urb_list);
 222         spin_unlock_irq(&channel->lock);
 223
 224         return urb;
 225 }
 226
 227 static int usbatm_submit_urb(struct urb *urb)
 228 {
 229         struct usbatm_channel *channel = urb->context;
 230         int ret;
 231
 232         vdbg("%s: submitting urb 0x%p, size %u",
 233              __func__, urb, urb->transfer_buffer_length);
 234
 235         ret = usb_submit_urb(urb, GFP_ATOMIC);
 236         if (ret) {
 237                 if (printk_ratelimit())
 238                         atm_warn(channel->usbatm, "%s: urb 0x%p submission failed (%d)!\n",
 239                                 __func__, urb, ret);
 240
 241                 /* consider all errors transient and return the buffer back to the queue */
 242                 urb->status = -EAGAIN;
 243                 spin_lock_irq(&channel->lock);
 244
 245                 /* must add to the front when sending; doesn't matter when receiving */
 246                 list_add(&urb->urb_list, &channel->list);
 247
 248                 spin_unlock_irq(&channel->lock);
 249
 250                 /* make sure the channel doesn't stall */
 251                 mod_timer(&channel->delay, jiffies + msecs_to_jiffies(THROTTLE_MSECS));
 252         }
 253
 254         return ret;
 255 }
 256
 257 static void usbatm_complete(struct urb *urb)
 258 {
 259         struct usbatm_channel *channel = urb->context;
 260         unsigned long flags;
 261
 262         vdbg("%s: urb 0x%p, status %d, actual_length %d",
 263              __func__, urb, urb->status, urb->actual_length);
 264
 265         /* usually in_interrupt(), but not always */
 266         spin_lock_irqsave(&channel->lock, flags);
 267
 268         /* must add to the back when receiving; doesn't matter when sending */
 269         list_add_tail(&urb->urb_list, &channel->list);
 270
 271         spin_unlock_irqrestore(&channel->lock, flags);
 272
 273         if (unlikely(urb->status) &&
 274                         (!(channel->usbatm->flags & UDSL_IGNORE_EILSEQ) ||
 275                          urb->status != -EILSEQ ))
 276         {
 277                 if (printk_ratelimit())
 278                         atm_warn(channel->usbatm, "%s: urb 0x%p failed (%d)!\n",
 279                                 __func__, urb, urb->status);
 280                 /* throttle processing in case of an error */
 281                 mod_timer(&channel->delay, jiffies + msecs_to_jiffies(THROTTLE_MSECS));
 282         } else
 283                 tasklet_schedule(&channel->tasklet);
 284 }
 285
 286
 287 /*************
 288 **  decode  **
 289 *************/
 290
 291 static inline struct usbatm_vcc_data *usbatm_find_vcc(struct usbatm_data *instance,
 292                                                   short vpi, int vci)
 293 {
 294         struct usbatm_vcc_data *vcc_data;
 295
 296         list_for_each_entry(vcc_data, &instance->vcc_list, list)
 297                 if ((vcc_data->vci == vci) && (vcc_data->vpi == vpi))
 298                         return vcc_data;
 299         return NULL;
 300 }
 301
 302 static void usbatm_extract_one_cell(struct usbatm_data *instance, unsigned char *source)
 303 {
 304         struct atm_vcc *vcc;
 305         struct sk_buff *sarb;
 306         short vpi = ((source[0] & 0x0f) << 4)  | (source[1] >> 4);
 307         int vci = ((source[1] & 0x0f) << 12) | (source[2] << 4) | (source[3] >> 4);
 308         u8 pti = ((source[3] & 0xe) >> 1);
 309
 310         vdbg("%s: vpi %hd, vci %d, pti %d", __func__, vpi, vci, pti);
 311
 312         if ((vci != instance->cached_vci) || (vpi != instance->cached_vpi)) {
 313                 instance->cached_vpi = vpi;
 314                 instance->cached_vci = vci;
 315
 316                 instance->cached_vcc = usbatm_find_vcc(instance, vpi, vci);
 317
 318                 if (!instance->cached_vcc)
 319                         atm_rldbg(instance, "%s: unknown vpi/vci (%hd/%d)!\n", __func__, vpi, vci);
 320         }
 321
 322         if (!instance->cached_vcc)
 323                 return;
 324
 325         vcc = instance->cached_vcc->vcc;
 326
 327         /* OAM F5 end-to-end */
 328         if (pti == ATM_PTI_E2EF5) {
 329                 if (printk_ratelimit())
 330                         atm_warn(instance, "%s: OAM not supported (vpi %d, vci %d)!\n",
 331                                 __func__, vpi, vci);
 332                 atomic_inc(&vcc->stats->rx_err);
 333                 return;
 334         }
 335
 336         sarb = instance->cached_vcc->sarb;
 337
 338         if (sarb->tail + ATM_CELL_PAYLOAD > sarb->end) {
 339                 atm_rldbg(instance, "%s: buffer overrun (sarb->len %u, vcc: 0x%p)!\n",
 340                                 __func__, sarb->len, vcc);
 341                 /* discard cells already received */
 342                 skb_trim(sarb, 0);
 343                 UDSL_ASSERT(sarb->tail + ATM_CELL_PAYLOAD <= sarb->end);
 344         }
 345
 346         memcpy(sarb->tail, source + ATM_CELL_HEADER, ATM_CELL_PAYLOAD);
 347         __skb_put(sarb, ATM_CELL_PAYLOAD);
 348
 349         if (pti & 1) {
 350                 struct sk_buff *skb;
 351                 unsigned int length;
 352                 unsigned int pdu_length;
 353
 354                 length = (source[ATM_CELL_SIZE - 6] << 8) + source[ATM_CELL_SIZE - 5];
 355
 356                 /* guard against overflow */
 357                 if (length > ATM_MAX_AAL5_PDU) {
 358                         atm_rldbg(instance, "%s: bogus length %u (vcc: 0x%p)!\n",
 359                                   __func__, length, vcc);
 360                         atomic_inc(&vcc->stats->rx_err);
 361                         goto out;
 362                 }
 363
 364                 pdu_length = usbatm_pdu_length(length);
 365
 366                 if (sarb->len < pdu_length) {
 367                         atm_rldbg(instance, "%s: bogus pdu_length %u (sarb->len: %u, vcc: 0x%p)!\n",
 368                                   __func__, pdu_length, sarb->len, vcc);
 369                         atomic_inc(&vcc->stats->rx_err);
 370                         goto out;
 371                 }
 372
 373                 if (crc32_be(~0, sarb->tail - pdu_length, pdu_length) != 0xc704dd7b) {
 374                         atm_rldbg(instance, "%s: packet failed crc check (vcc: 0x%p)!\n",
 375                                   __func__, vcc);
 376                         atomic_inc(&vcc->stats->rx_err);
 377                         goto out;
 378                 }
 379
 380                 vdbg("%s: got packet (length: %u, pdu_length: %u, vcc: 0x%p)", __func__, length, pdu_length, vcc);
 381
 382                 if (!(skb = dev_alloc_skb(length))) {
 383                         if (printk_ratelimit())
 384                                 atm_err(instance, "%s: no memory for skb (length: %u)!\n",
 385                                         __func__, length);
 386                         atomic_inc(&vcc->stats->rx_drop);
 387                         goto out;
 388                 }
 389
 390                 vdbg("%s: allocated new sk_buff (skb: 0x%p, skb->truesize: %u)", __func__, skb, skb->truesize);
 391
 392                 if (!atm_charge(vcc, skb->truesize)) {
 393                         atm_rldbg(instance, "%s: failed atm_charge (skb->truesize: %u)!\n",
 394                                   __func__, skb->truesize);
 395                         dev_kfree_skb_any(skb);
 396                         goto out;       /* atm_charge increments rx_drop */
 397                 }
 398
 399                 memcpy(skb->data, sarb->tail - pdu_length, length);
 400                 __skb_put(skb, length);
 401
 402                 vdbg("%s: sending skb 0x%p, skb->len %u, skb->truesize %u",
 403                      __func__, skb, skb->len, skb->truesize);
 404
 405                 PACKETDEBUG(skb->data, skb->len);
 406
 407                 vcc->push(vcc, skb);
 408
 409                 atomic_inc(&vcc->stats->rx);
 410         out:
 411                 skb_trim(sarb, 0);
 412         }
 413 }
 414
 415 static void usbatm_extract_cells(struct usbatm_data *instance,
 416                 unsigned char *source, unsigned int avail_data)
 417 {
 418         unsigned int stride = instance->rx_channel.stride;
 419         unsigned int buf_usage = instance->buf_usage;
 420
 421         /* extract cells from incoming data, taking into account that
 422          * the length of avail data may not be a multiple of stride */
 423
 424         if (buf_usage > 0) {
 425                 /* we have a partially received atm cell */
 426                 unsigned char *cell_buf = instance->cell_buf;
 427                 unsigned int space_left = stride - buf_usage;
 428
 429                 UDSL_ASSERT(buf_usage <= stride);
 430
 431                 if (avail_data >= space_left) {
 432                         /* add new data and process cell */
 433                         memcpy(cell_buf + buf_usage, source, space_left);
 434                         source += space_left;
 435                         avail_data -= space_left;
 436                         usbatm_extract_one_cell(instance, cell_buf);
 437                         instance->buf_usage = 0;
 438                 } else {
 439                         /* not enough data to fill the cell */
 440                         memcpy(cell_buf + buf_usage, source, avail_data);
 441                         instance->buf_usage = buf_usage + avail_data;
 442                         return;
 443                 }
 444         }
 445
 446         for (; avail_data >= stride; avail_data -= stride, source += stride)
 447                 usbatm_extract_one_cell(instance, source);
 448
 449         if (avail_data > 0) {
 450                 /* length was not a multiple of stride -
 451                  * save remaining data for next call */
 452                 memcpy(instance->cell_buf, source, avail_data);
 453                 instance->buf_usage = avail_data;
 454         }
 455 }
 456
 457
 458 /*************
 459 **  encode  **
 460 *************/
 461
 462 static unsigned int usbatm_write_cells(struct usbatm_data *instance,
 463                                        struct sk_buff *skb,
 464                                        u8 *target, unsigned int avail_space)
 465 {
 466         struct usbatm_control *ctrl = UDSL_SKB(skb);
 467         struct atm_vcc *vcc = ctrl->atm.vcc;
 468         unsigned int bytes_written;
 469         unsigned int stride = instance->tx_channel.stride;
 470
 471         vdbg("%s: skb->len=%d, avail_space=%u", __func__, skb->len, avail_space);
 472         UDSL_ASSERT(!(avail_space % stride));
 473
 474         for (bytes_written = 0; bytes_written < avail_space && ctrl->len;
 475              bytes_written += stride, target += stride) {
 476                 unsigned int data_len = min_t(unsigned int, skb->len, ATM_CELL_PAYLOAD);
 477                 unsigned int left = ATM_CELL_PAYLOAD - data_len;
 478                 u8 *ptr = target;
 479
 480                 ptr[0] = vcc->vpi >> 4;
 481                 ptr[1] = (vcc->vpi << 4) | (vcc->vci >> 12);
 482                 ptr[2] = vcc->vci >> 4;
 483                 ptr[3] = vcc->vci << 4;
 484                 ptr[4] = 0xec;
 485                 ptr += ATM_CELL_HEADER;
 486
 487                 memcpy(ptr, skb->data, data_len);
 488                 ptr += data_len;
 489                 __skb_pull(skb, data_len);
 490
 491                 if(!left)
 492                         continue;
 493
 494                 memset(ptr, 0, left);
 495
 496                 if (left >= ATM_AAL5_TRAILER) { /* trailer will go in this cell */
 497                         u8 *trailer = target + ATM_CELL_SIZE - ATM_AAL5_TRAILER;
 498                         /* trailer[0] = 0;              UU = 0 */
 499                         /* trailer[1] = 0;              CPI = 0 */
 500                         trailer[2] = ctrl->len >> 8;
 501                         trailer[3] = ctrl->len;
 502
 503                         ctrl->crc = ~ crc32_be(ctrl->crc, ptr, left - 4);
 504
 505                         trailer[4] = ctrl->crc >> 24;
 506                         trailer[5] = ctrl->crc >> 16;
 507                         trailer[6] = ctrl->crc >> 8;
 508                         trailer[7] = ctrl->crc;
 509
 510                         target[3] |= 0x2;       /* adjust PTI */
 511
 512                         ctrl->len = 0;          /* tag this skb finished */
 513                 }
 514                 else
 515                         ctrl->crc = crc32_be(ctrl->crc, ptr, left);
 516         }
 517
 518         return bytes_written;
 519 }
 520
 521
 522 /**************
 523 **  receive  **
 524 **************/
 525
 526 static void usbatm_rx_process(unsigned long data)
 527 {
 528         struct usbatm_data *instance = (struct usbatm_data *)data;
 529         struct urb *urb;
 530
 531         while ((urb = usbatm_pop_urb(&instance->rx_channel))) {
 532                 vdbg("%s: processing urb 0x%p", __func__, urb);
 533
 534                 if (usb_pipeisoc(urb->pipe)) {
 535                         unsigned char *merge_start = NULL;
 536                         unsigned int merge_length = 0;
 537                         const unsigned int packet_size = instance->rx_channel.packet_size;
 538                         int i;
 539
 540                         for (i = 0; i < urb->number_of_packets; i++) {
 541                                 if (!urb->iso_frame_desc[i].status) {
 542                                         unsigned int actual_length = urb->iso_frame_desc[i].actual_length;
 543
 544                                         UDSL_ASSERT(actual_length <= packet_size);
 545
 546                                         if (!merge_length)
 547                                                 merge_start = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
 548                                         merge_length += actual_length;
 549                                         if (merge_length && (actual_length < packet_size)) {
 550                                                 usbatm_extract_cells(instance, merge_start, merge_length);
 551                                                 merge_length = 0;
 552                                         }
 553                                 } else {
 554                                         atm_rldbg(instance, "%s: status %d in frame %d!\n", __func__, urb->status, i);
 555                                         if (merge_length)
 556                                                 usbatm_extract_cells(instance, merge_start, merge_length);
 557                                         merge_length = 0;
 558                                         instance->buf_usage = 0;
 559                                 }
 560                         }
 561
 562                         if (merge_length)
 563                                 usbatm_extract_cells(instance, merge_start, merge_length);
 564                 } else
 565                         if (!urb->status)
 566                                 usbatm_extract_cells(instance, urb->transfer_buffer, urb->actual_length);
 567                         else
 568                                 instance->buf_usage = 0;
 569
 570                 if (usbatm_submit_urb(urb))
 571                         return;
 572         }
 573 }
 574
 575
 576 /***********
 577 **  send  **
 578 ***********/
 579
 580 static void usbatm_tx_process(unsigned long data)
 581 {
 582         struct usbatm_data *instance = (struct usbatm_data *)data;
 583         struct sk_buff *skb = instance->current_skb;
 584         struct urb *urb = NULL;
 585         const unsigned int buf_size = instance->tx_channel.buf_size;
 586         unsigned int bytes_written = 0;
 587         u8 *buffer = NULL;
 588
 589         if (!skb)
 590                 skb = skb_dequeue(&instance->sndqueue);
 591
 592         while (skb) {
 593                 if (!urb) {
 594                         urb = usbatm_pop_urb(&instance->tx_channel);
 595                         if (!urb)
 596                                 break;          /* no more senders */
 597                         buffer = urb->transfer_buffer;
 598                         bytes_written = (urb->status == -EAGAIN) ?
 599                                 urb->transfer_buffer_length : 0;
 600                 }
 601
 602                 bytes_written += usbatm_write_cells(instance, skb,
 603                                                   buffer + bytes_written,
 604                                                   buf_size - bytes_written);
 605
 606                 vdbg("%s: wrote %u bytes from skb 0x%p to urb 0x%p",
 607                      __func__, bytes_written, skb, urb);
 608
 609                 if (!UDSL_SKB(skb)->len) {
 610                         struct atm_vcc *vcc = UDSL_SKB(skb)->atm.vcc;
 611
 612                         usbatm_pop(vcc, skb);
 613                         atomic_inc(&vcc->stats->tx);
 614
 615                         skb = skb_dequeue(&instance->sndqueue);
 616                 }
 617
 618                 if (bytes_written == buf_size || (!skb && bytes_written)) {
 619                         urb->transfer_buffer_length = bytes_written;
 620
 621                         if (usbatm_submit_urb(urb))
 622                                 break;
 623                         urb = NULL;
 624                 }
 625         }
 626
 627         instance->current_skb = skb;
 628 }
 629
 630 static void usbatm_cancel_send(struct usbatm_data *instance,
 631                                struct atm_vcc *vcc)
 632 {
 633         struct sk_buff *skb, *n;
 634
 635         atm_dbg(instance, "%s entered\n", __func__);
 636         spin_lock_irq(&instance->sndqueue.lock);
 637         for (skb = instance->sndqueue.next, n = skb->next;
 638              skb != (struct sk_buff *)&instance->sndqueue;
 639              skb = n, n = skb->next)
 640                 if (UDSL_SKB(skb)->atm.vcc == vcc) {
 641                         atm_dbg(instance, "%s: popping skb 0x%p\n", __func__, skb);
 642                         __skb_unlink(skb, &instance->sndqueue);
 643                         usbatm_pop(vcc, skb);
 644                 }
 645         spin_unlock_irq(&instance->sndqueue.lock);
 646
 647         tasklet_disable(&instance->tx_channel.tasklet);
 648         if ((skb = instance->current_skb) && (UDSL_SKB(skb)->atm.vcc == vcc)) {
 649                 atm_dbg(instance, "%s: popping current skb (0x%p)\n", __func__, skb);
 650                 instance->current_skb = NULL;
 651                 usbatm_pop(vcc, skb);
 652         }
 653         tasklet_enable(&instance->tx_channel.tasklet);
 654         atm_dbg(instance, "%s done\n", __func__);
 655 }
 656
 657 static int usbatm_atm_send(struct atm_vcc *vcc, struct sk_buff *skb)
 658 {
 659         struct usbatm_data *instance = vcc->dev->dev_data;
 660         struct usbatm_control *ctrl = UDSL_SKB(skb);
 661         int err;
 662
 663         vdbg("%s called (skb 0x%p, len %u)", __func__, skb, skb->len);
 664
 665         /* racy disconnection check - fine */
 666         if (!instance || instance->disconnected) {
 667 #ifdef DEBUG
 668                 if (printk_ratelimit())
 669                         printk(KERN_DEBUG "%s: %s!\n", __func__, instance ? "disconnected" : "NULL instance");
 670 #endif
 671                 err = -ENODEV;
 672                 goto fail;
 673         }
 674
 675         if (vcc->qos.aal != ATM_AAL5) {
 676                 atm_rldbg(instance, "%s: unsupported ATM type %d!\n", __func__, vcc->qos.aal);
 677                 err = -EINVAL;
 678                 goto fail;
 679         }
 680
 681         if (skb->len > ATM_MAX_AAL5_PDU) {
 682                 atm_rldbg(instance, "%s: packet too long (%d vs %d)!\n",
 683                                 __func__, skb->len, ATM_MAX_AAL5_PDU);
 684                 err = -EINVAL;
 685                 goto fail;
 686         }
 687
 688         PACKETDEBUG(skb->data, skb->len);
 689
 690         /* initialize the control block */
 691         ctrl->atm.vcc = vcc;
 692         ctrl->len = skb->len;
 693         ctrl->crc = crc32_be(~0, skb->data, skb->len);
 694
 695         skb_queue_tail(&instance->sndqueue, skb);
 696         tasklet_schedule(&instance->tx_channel.tasklet);
 697
 698         return 0;
 699
 700  fail:
 701         usbatm_pop(vcc, skb);
 702         return err;
 703 }
 704
 705
 706 /********************
 707 **  bean counting  **
 708 ********************/
 709
 710 static void usbatm_destroy_instance(struct kref *kref)
 711 {
 712         struct usbatm_data *instance = container_of(kref, struct usbatm_data, refcount);
 713
 714         dbg("%s", __func__);
 715
 716         tasklet_kill(&instance->rx_channel.tasklet);
 717         tasklet_kill(&instance->tx_channel.tasklet);
 718         usb_put_dev(instance->usb_dev);
 719         kfree(instance);
 720 }
 721
 722 static void usbatm_get_instance(struct usbatm_data *instance)
 723 {
 724         dbg("%s", __func__);
 725
 726         kref_get(&instance->refcount);
 727 }
 728
 729 static void usbatm_put_instance(struct usbatm_data *instance)
 730 {
 731         dbg("%s", __func__);
 732
 733         kref_put(&instance->refcount, usbatm_destroy_instance);
 734 }
 735
 736
 737 /**********
 738 **  ATM  **
 739 **********/
 740
 741 static void usbatm_atm_dev_close(struct atm_dev *atm_dev)
 742 {
 743         struct usbatm_data *instance = atm_dev->dev_data;
 744
 745         dbg("%s", __func__);
 746
 747         if (!instance)
 748                 return;
 749
 750         atm_dev->dev_data = NULL; /* catch bugs */
 751         usbatm_put_instance(instance);  /* taken in usbatm_atm_init */
 752 }
 753
 754 static int usbatm_atm_proc_read(struct atm_dev *atm_dev, loff_t * pos, char *page)
 755 {
 756         struct usbatm_data *instance = atm_dev->dev_data;
 757         int left = *pos;
 758
 759         if (!instance) {
 760                 dbg("%s: NULL instance!", __func__);
 761                 return -ENODEV;
 762         }
 763
 764         if (!left--)
 765                 return sprintf(page, "%s\n", instance->description);
 766
 767         if (!left--)
 768                 return sprintf(page, "MAC: %02x:%02x:%02x:%02x:%02x:%02x\n",
 769                                atm_dev->esi[0], atm_dev->esi[1],
 770                                atm_dev->esi[2], atm_dev->esi[3],
 771                                atm_dev->esi[4], atm_dev->esi[5]);
 772
 773         if (!left--)
 774                 return sprintf(page,
 775                                "AAL5: tx %d ( %d err ), rx %d ( %d err, %d drop )\n",
 776                                atomic_read(&atm_dev->stats.aal5.tx),
 777                                atomic_read(&atm_dev->stats.aal5.tx_err),
 778                                atomic_read(&atm_dev->stats.aal5.rx),
 779                                atomic_read(&atm_dev->stats.aal5.rx_err),
 780                                atomic_read(&atm_dev->stats.aal5.rx_drop));
 781
 782         if (!left--) {
 783                 if (instance->disconnected)
 784                         return sprintf(page, "Disconnected\n");
 785                 else
 786                         switch (atm_dev->signal) {
 787                         case ATM_PHY_SIG_FOUND:
 788                                 return sprintf(page, "Line up\n");
 789                         case ATM_PHY_SIG_LOST:
 790                                 return sprintf(page, "Line down\n");
 791                         default:
 792                                 return sprintf(page, "Line state unknown\n");
 793                         }
 794         }
 795
 796         return 0;
 797 }
 798
 799 static int usbatm_atm_open(struct atm_vcc *vcc)
 800 {
 801         struct usbatm_data *instance = vcc->dev->dev_data;
 802         struct usbatm_vcc_data *new = NULL;
 803         int ret;
 804         int vci = vcc->vci;
 805         short vpi = vcc->vpi;
 806
 807         if (!instance) {
 808                 dbg("%s: NULL data!", __func__);
 809                 return -ENODEV;
 810         }
 811
 812         atm_dbg(instance, "%s: vpi %hd, vci %d\n", __func__, vpi, vci);
 813
 814         /* only support AAL5 */
 815         if ((vcc->qos.aal != ATM_AAL5)) {
 816                 atm_warn(instance, "%s: unsupported ATM type %d!\n", __func__, vcc->qos.aal);
 817                 return -EINVAL;
 818         }
 819
 820         /* sanity checks */
 821         if ((vcc->qos.rxtp.max_sdu < 0) || (vcc->qos.rxtp.max_sdu > ATM_MAX_AAL5_PDU)) {
 822                 atm_dbg(instance, "%s: max_sdu %d out of range!\n", __func__, vcc->qos.rxtp.max_sdu);
 823                 return -EINVAL;
 824         }
 825
 826         mutex_lock(&instance->serialize);       /* vs self, usbatm_atm_close, usbatm_usb_disconnect */
 827
 828         if (instance->disconnected) {
 829                 atm_dbg(instance, "%s: disconnected!\n", __func__);
 830                 ret = -ENODEV;
 831                 goto fail;
 832         }
 833
 834         if (usbatm_find_vcc(instance, vpi, vci)) {
 835                 atm_dbg(instance, "%s: %hd/%d already in use!\n", __func__, vpi, vci);
 836                 ret = -EADDRINUSE;
 837                 goto fail;
 838         }
 839
 840         if (!(new = kzalloc(sizeof(struct usbatm_vcc_data), GFP_KERNEL))) {
 841                 atm_err(instance, "%s: no memory for vcc_data!\n", __func__);
 842                 ret = -ENOMEM;
 843                 goto fail;
 844         }
 845
 846         new->vcc = vcc;
 847         new->vpi = vpi;
 848         new->vci = vci;
 849
 850         new->sarb = alloc_skb(usbatm_pdu_length(vcc->qos.rxtp.max_sdu), GFP_KERNEL);
 851         if (!new->sarb) {
 852                 atm_err(instance, "%s: no memory for SAR buffer!\n", __func__);
 853                 ret = -ENOMEM;
 854                 goto fail;
 855         }
 856
 857         vcc->dev_data = new;
 858
 859         tasklet_disable(&instance->rx_channel.tasklet);
 860         instance->cached_vcc = new;
 861         instance->cached_vpi = vpi;
 862         instance->cached_vci = vci;
 863         list_add(&new->list, &instance->vcc_list);
 864         tasklet_enable(&instance->rx_channel.tasklet);
 865
 866         set_bit(ATM_VF_ADDR, &vcc->flags);
 867         set_bit(ATM_VF_PARTIAL, &vcc->flags);
 868         set_bit(ATM_VF_READY, &vcc->flags);
 869
 870         mutex_unlock(&instance->serialize);
 871
 872         atm_dbg(instance, "%s: allocated vcc data 0x%p\n", __func__, new);
 873
 874         return 0;
 875
 876 fail:
 877         kfree(new);
 878         mutex_unlock(&instance->serialize);
 879         return ret;
 880 }
 881
 882 static void usbatm_atm_close(struct atm_vcc *vcc)
 883 {
 884         struct usbatm_data *instance = vcc->dev->dev_data;
 885         struct usbatm_vcc_data *vcc_data = vcc->dev_data;
 886
 887         if (!instance || !vcc_data) {
 888                 dbg("%s: NULL data!", __func__);
 889                 return;
 890         }
 891
 892         atm_dbg(instance, "%s entered\n", __func__);
 893
 894         atm_dbg(instance, "%s: deallocating vcc 0x%p with vpi %d vci %d\n",
 895                 __func__, vcc_data, vcc_data->vpi, vcc_data->vci);
 896
 897         usbatm_cancel_send(instance, vcc);
 898
 899         mutex_lock(&instance->serialize);       /* vs self, usbatm_atm_open, usbatm_usb_disconnect */
 900
 901         tasklet_disable(&instance->rx_channel.tasklet);
 902         if (instance->cached_vcc == vcc_data) {
 903                 instance->cached_vcc = NULL;
 904                 instance->cached_vpi = ATM_VPI_UNSPEC;
 905                 instance->cached_vci = ATM_VCI_UNSPEC;
 906         }
 907         list_del(&vcc_data->list);
 908         tasklet_enable(&instance->rx_channel.tasklet);
 909
 910         kfree_skb(vcc_data->sarb);
 911         vcc_data->sarb = NULL;
 912
 913         kfree(vcc_data);
 914         vcc->dev_data = NULL;
 915
 916         vcc->vpi = ATM_VPI_UNSPEC;
 917         vcc->vci = ATM_VCI_UNSPEC;
 918         clear_bit(ATM_VF_READY, &vcc->flags);
 919         clear_bit(ATM_VF_PARTIAL, &vcc->flags);
 920         clear_bit(ATM_VF_ADDR, &vcc->flags);
 921
 922         mutex_unlock(&instance->serialize);
 923
 924         atm_dbg(instance, "%s successful\n", __func__);
 925 }
 926
 927 static int usbatm_atm_ioctl(struct atm_dev *atm_dev, unsigned int cmd,
 928                           void __user * arg)
 929 {
 930         struct usbatm_data *instance = atm_dev->dev_data;
 931
 932         if (!instance || instance->disconnected) {
 933                 dbg("%s: %s!", __func__, instance ? "disconnected" : "NULL instance");
 934                 return -ENODEV;
 935         }
 936
 937         switch (cmd) {
 938         case ATM_QUERYLOOP:
 939                 return put_user(ATM_LM_NONE, (int __user *)arg) ? -EFAULT : 0;
 940         default:
 941                 return -ENOIOCTLCMD;
 942         }
 943 }
 944
 945 static int usbatm_atm_init(struct usbatm_data *instance)
 946 {
 947         struct atm_dev *atm_dev;
 948         int ret, i;
 949
 950         /* ATM init.  The ATM initialization scheme suffers from an intrinsic race
 951          * condition: callbacks we register can be executed at once, before we have
 952          * initialized the struct atm_dev.  To protect against this, all callbacks
 953          * abort if atm_dev->dev_data is NULL. */
 954         atm_dev = atm_dev_register(instance->driver_name, &usbatm_atm_devops, -1, NULL);
 955         if (!atm_dev) {
 956                 usb_err(instance, "%s: failed to register ATM device!\n", __func__);
 957                 return -1;
 958         }
 959
 960         instance->atm_dev = atm_dev;
 961
 962         atm_dev->ci_range.vpi_bits = ATM_CI_MAX;
 963         atm_dev->ci_range.vci_bits = ATM_CI_MAX;
 964         atm_dev->signal = ATM_PHY_SIG_UNKNOWN;
 965
 966         /* temp init ATM device, set to 128kbit */
 967         atm_dev->link_rate = 128 * 1000 / 424;
 968
 969         if (instance->driver->atm_start && ((ret = instance->driver->atm_start(instance, atm_dev)) < 0)) {
 970                 atm_err(instance, "%s: atm_start failed: %d!\n", __func__, ret);
 971                 goto fail;
 972         }
 973
 974         usbatm_get_instance(instance);  /* dropped in usbatm_atm_dev_close */
 975
 976         /* ready for ATM callbacks */
 977         mb();
 978         atm_dev->dev_data = instance;
 979
 980         /* submit all rx URBs */
 981         for (i = 0; i < num_rcv_urbs; i++)
 982                 usbatm_submit_urb(instance->urbs[i]);
 983
 984         return 0;
 985
 986  fail:
 987         instance->atm_dev = NULL;
 988         atm_dev_deregister(atm_dev); /* usbatm_atm_dev_close will eventually be called */
 989         return ret;
 990 }
 991
 992
 993 /**********
 994 **  USB  **
 995 **********/
 996
 997 static int usbatm_do_heavy_init(void *arg)
 998 {
 999         struct usbatm_data *instance = arg;
1000         int ret;
1001
1002         daemonize(instance->driver->driver_name);
1003         allow_signal(SIGTERM);
1004         instance->thread_pid = current->pid;
1005
1006         complete(&instance->thread_started);
1007
1008         ret = instance->driver->heavy_init(instance, instance->usb_intf);
1009
1010         if (!ret)
1011                 ret = usbatm_atm_init(instance);
1012
1013         mutex_lock(&instance->serialize);
1014         instance->thread_pid = -1;
1015         mutex_unlock(&instance->serialize);
1016
1017         complete_and_exit(&instance->thread_exited, ret);
1018 }
1019
1020 static int usbatm_heavy_init(struct usbatm_data *instance)
1021 {
1022         int ret = kernel_thread(usbatm_do_heavy_init, instance, CLONE_KERNEL);
1023
1024         if (ret < 0) {
1025                 usb_err(instance, "%s: failed to create kernel_thread (%d)!\n", __func__, ret);
1026                 return ret;
1027         }
1028
1029         wait_for_completion(&instance->thread_started);
1030
1031         return 0;
1032 }
1033
1034 static void usbatm_tasklet_schedule(unsigned long data)
1035 {
1036         tasklet_schedule((struct tasklet_struct *) data);
1037 }
1038
1039 static void usbatm_init_channel(struct usbatm_channel *channel)
1040 {
1041         spin_lock_init(&channel->lock);
1042         INIT_LIST_HEAD(&channel->list);
1043         channel->delay.function = usbatm_tasklet_schedule;
1044         channel->delay.data = (unsigned long) &channel->tasklet;
1045         init_timer(&channel->delay);
1046 }
1047
1048 int usbatm_usb_probe(struct usb_interface *intf, const struct usb_device_id *id,
1049                      struct usbatm_driver *driver)
1050 {
1051         struct device *dev = &intf->dev;
1052         struct usb_device *usb_dev = interface_to_usbdev(intf);
1053         struct usbatm_data *instance;
1054         char *buf;
1055         int error = -ENOMEM;
1056         int i, length;
1057         unsigned int maxpacket, num_packets;
1058
1059         dev_dbg(dev, "%s: trying driver %s with vendor=%04x, product=%04x, ifnum %2d\n",
1060                         __func__, driver->driver_name,
1061                         le16_to_cpu(usb_dev->descriptor.idVendor),
1062                         le16_to_cpu(usb_dev->descriptor.idProduct),
1063                         intf->altsetting->desc.bInterfaceNumber);
1064
1065         /* instance init */
1066         instance = kzalloc(sizeof(*instance) + sizeof(struct urb *) * (num_rcv_urbs + num_snd_urbs), GFP_KERNEL);
1067         if (!instance) {
1068                 dev_err(dev, "%s: no memory for instance data!\n", __func__);
1069                 return -ENOMEM;
1070         }
1071
1072         /* public fields */
1073
1074         instance->driver = driver;
1075         snprintf(instance->driver_name, sizeof(instance->driver_name), driver->driver_name);
1076
1077         instance->usb_dev = usb_dev;
1078         instance->usb_intf = intf;
1079
1080         buf = instance->description;
1081         length = sizeof(instance->description);
1082
1083         if ((i = usb_string(usb_dev, usb_dev->descriptor.iProduct, buf, length)) < 0)
1084                 goto bind;
1085
1086         buf += i;
1087         length -= i;
1088
1089         i = scnprintf(buf, length, " (");
1090         buf += i;
1091         length -= i;
1092
1093         if (length <= 0 || (i = usb_make_path(usb_dev, buf, length)) < 0)
1094                 goto bind;
1095
1096         buf += i;
1097         length -= i;
1098
1099         snprintf(buf, length, ")");
1100
1101  bind:
1102         if (driver->bind && (error = driver->bind(instance, intf, id)) < 0) {
1103                         dev_err(dev, "%s: bind failed: %d!\n", __func__, error);
1104                         goto fail_free;
1105         }
1106
1107         /* private fields */
1108
1109         kref_init(&instance->refcount);         /* dropped in usbatm_usb_disconnect */
1110         mutex_init(&instance->serialize);
1111
1112         instance->thread_pid = -1;
1113         init_completion(&instance->thread_started);
1114         init_completion(&instance->thread_exited);
1115
1116         INIT_LIST_HEAD(&instance->vcc_list);
1117         skb_queue_head_init(&instance->sndqueue);
1118
1119         usbatm_init_channel(&instance->rx_channel);
1120         usbatm_init_channel(&instance->tx_channel);
1121         tasklet_init(&instance->rx_channel.tasklet, usbatm_rx_process, (unsigned long)instance);
1122         tasklet_init(&instance->tx_channel.tasklet, usbatm_tx_process, (unsigned long)instance);
1123         instance->rx_channel.stride = ATM_CELL_SIZE + driver->rx_padding;
1124         instance->tx_channel.stride = ATM_CELL_SIZE + driver->tx_padding;
1125         instance->rx_channel.usbatm = instance->tx_channel.usbatm = instance;
1126
1127         if ((instance->flags & UDSL_USE_ISOC) && driver->isoc_in)
1128                 instance->rx_channel.endpoint = usb_rcvisocpipe(usb_dev, driver->isoc_in);
1129         else
1130                 instance->rx_channel.endpoint = usb_rcvbulkpipe(usb_dev, driver->bulk_in);
1131
1132         instance->tx_channel.endpoint = usb_sndbulkpipe(usb_dev, driver->bulk_out);
1133
1134         /* tx buffer size must be a positive multiple of the stride */
1135         instance->tx_channel.buf_size = max (instance->tx_channel.stride,
1136                         snd_buf_bytes - (snd_buf_bytes % instance->tx_channel.stride));
1137
1138         /* rx buffer size must be a positive multiple of the endpoint maxpacket */
1139         maxpacket = usb_maxpacket(usb_dev, instance->rx_channel.endpoint, 0);
1140
1141         if ((maxpacket < 1) || (maxpacket > UDSL_MAX_BUF_SIZE)) {
1142                 dev_err(dev, "%s: invalid endpoint %02x!\n", __func__,
1143                                 usb_pipeendpoint(instance->rx_channel.endpoint));
1144                 error = -EINVAL;
1145                 goto fail_unbind;
1146         }
1147
1148         num_packets = max (1U, (rcv_buf_bytes + maxpacket / 2) / maxpacket); /* round */
1149
1150         if (num_packets * maxpacket > UDSL_MAX_BUF_SIZE)
1151                 num_packets--;
1152
1153         instance->rx_channel.buf_size = num_packets * maxpacket;
1154         instance->rx_channel.packet_size = maxpacket;
1155
1156 #ifdef DEBUG
1157         for (i = 0; i < 2; i++) {
1158                 struct usbatm_channel *channel = i ?
1159                         &instance->tx_channel : &instance->rx_channel;
1160
1161                 dev_dbg(dev, "%s: using %d byte buffer for %s channel 0x%p\n", __func__, channel->buf_size, i ? "tx" : "rx", channel);
1162         }
1163 #endif
1164
1165         /* initialize urbs */
1166
1167         for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) {
1168                 u8 *buffer;
1169                 struct usbatm_channel *channel = i < num_rcv_urbs ?
1170                         &instance->rx_channel : &instance->tx_channel;
1171                 struct urb *urb;
1172                 unsigned int iso_packets = usb_pipeisoc(channel->endpoint) ? channel->buf_size / channel->packet_size : 0;
1173
1174                 UDSL_ASSERT(!usb_pipeisoc(channel->endpoint) || usb_pipein(channel->endpoint));
1175
1176                 urb = usb_alloc_urb(iso_packets, GFP_KERNEL);
1177                 if (!urb) {
1178                         dev_err(dev, "%s: no memory for urb %d!\n", __func__, i);
1179                         error = -ENOMEM;
1180                         goto fail_unbind;
1181                 }
1182
1183                 instance->urbs[i] = urb;
1184
1185                 /* zero the tx padding to avoid leaking information */
1186                 buffer = kzalloc(channel->buf_size, GFP_KERNEL);
1187                 if (!buffer) {
1188                         dev_err(dev, "%s: no memory for buffer %d!\n", __func__, i);
1189                         error = -ENOMEM;
1190                         goto fail_unbind;
1191                 }
1192
1193                 usb_fill_bulk_urb(urb, instance->usb_dev, channel->endpoint,
1194                                   buffer, channel->buf_size, usbatm_complete, channel);
1195                 if (iso_packets) {
1196                         int j;
1197                         urb->interval = 1;
1198                         urb->transfer_flags = URB_ISO_ASAP;
1199                         urb->number_of_packets = iso_packets;
1200                         for (j = 0; j < iso_packets; j++) {
1201                                 urb->iso_frame_desc[j].offset = channel->packet_size * j;
1202                                 urb->iso_frame_desc[j].length = channel->packet_size;
1203                         }
1204                 }
1205
1206                 /* put all tx URBs on the list of spares */
1207                 if (i >= num_rcv_urbs)
1208                         list_add_tail(&urb->urb_list, &channel->list);
1209
1210                 vdbg("%s: alloced buffer 0x%p buf size %u urb 0x%p",
1211                      __func__, urb->transfer_buffer, urb->transfer_buffer_length, urb);
1212         }
1213
1214         instance->cached_vpi = ATM_VPI_UNSPEC;
1215         instance->cached_vci = ATM_VCI_UNSPEC;
1216         instance->cell_buf = kmalloc(instance->rx_channel.stride, GFP_KERNEL);
1217
1218         if (!instance->cell_buf) {
1219                 dev_err(dev, "%s: no memory for cell buffer!\n", __func__);
1220                 error = -ENOMEM;
1221                 goto fail_unbind;
1222         }
1223
1224         if (!(instance->flags & UDSL_SKIP_HEAVY_INIT) && driver->heavy_init) {
1225                 error = usbatm_heavy_init(instance);
1226         } else {
1227                 complete(&instance->thread_exited);     /* pretend that heavy_init was run */
1228                 error = usbatm_atm_init(instance);
1229         }
1230
1231         if (error < 0)
1232                 goto fail_unbind;
1233
1234         usb_get_dev(usb_dev);
1235         usb_set_intfdata(intf, instance);
1236
1237         return 0;
1238
1239  fail_unbind:
1240         if (instance->driver->unbind)
1241                 instance->driver->unbind(instance, intf);
1242  fail_free:
1243         kfree(instance->cell_buf);
1244
1245         for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) {
1246                 if (instance->urbs[i])
1247                         kfree(instance->urbs[i]->transfer_buffer);
1248                 usb_free_urb(instance->urbs[i]);
1249         }
1250
1251         kfree (instance);
1252
1253         return error;
1254 }
1255 EXPORT_SYMBOL_GPL(usbatm_usb_probe);
1256
1257 void usbatm_usb_disconnect(struct usb_interface *intf)
1258 {
1259         struct device *dev = &intf->dev;
1260         struct usbatm_data *instance = usb_get_intfdata(intf);
1261         struct usbatm_vcc_data *vcc_data;
1262         int i;
1263
1264         dev_dbg(dev, "%s entered\n", __func__);
1265
1266         if (!instance) {
1267                 dev_dbg(dev, "%s: NULL instance!\n", __func__);
1268                 return;
1269         }
1270
1271         usb_set_intfdata(intf, NULL);
1272
1273         mutex_lock(&instance->serialize);
1274         instance->disconnected = 1;
1275         if (instance->thread_pid >= 0)
1276                 kill_proc(instance->thread_pid, SIGTERM, 1);
1277         mutex_unlock(&instance->serialize);
1278
1279         wait_for_completion(&instance->thread_exited);
1280
1281         mutex_lock(&instance->serialize);
1282         list_for_each_entry(vcc_data, &instance->vcc_list, list)
1283                 vcc_release_async(vcc_data->vcc, -EPIPE);
1284         mutex_unlock(&instance->serialize);
1285
1286         tasklet_disable(&instance->rx_channel.tasklet);
1287         tasklet_disable(&instance->tx_channel.tasklet);
1288
1289         for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++)
1290                 usb_kill_urb(instance->urbs[i]);
1291
1292         del_timer_sync(&instance->rx_channel.delay);
1293         del_timer_sync(&instance->tx_channel.delay);
1294
1295         /* turn usbatm_[rt]x_process into something close to a no-op */
1296         /* no need to take the spinlock */
1297         INIT_LIST_HEAD(&instance->rx_channel.list);
1298         INIT_LIST_HEAD(&instance->tx_channel.list);
1299
1300         tasklet_enable(&instance->rx_channel.tasklet);
1301         tasklet_enable(&instance->tx_channel.tasklet);
1302
1303         if (instance->atm_dev && instance->driver->atm_stop)
1304                 instance->driver->atm_stop(instance, instance->atm_dev);
1305
1306         if (instance->driver->unbind)
1307                 instance->driver->unbind(instance, intf);
1308
1309         instance->driver_data = NULL;
1310
1311         for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) {
1312                 kfree(instance->urbs[i]->transfer_buffer);
1313                 usb_free_urb(instance->urbs[i]);
1314         }
1315
1316         kfree(instance->cell_buf);
1317
1318         /* ATM finalize */
1319         if (instance->atm_dev)
1320                 atm_dev_deregister(instance->atm_dev);
1321
1322         usbatm_put_instance(instance);  /* taken in usbatm_usb_probe */
1323 }
1324 EXPORT_SYMBOL_GPL(usbatm_usb_disconnect);
1325
1326
1327 /***********
1328 **  init  **
1329 ***********/
1330
1331 static int __init usbatm_usb_init(void)
1332 {
1333         dbg("%s: driver version %s", __func__, DRIVER_VERSION);
1334
1335         if (sizeof(struct usbatm_control) > sizeof(((struct sk_buff *) 0)->cb)) {
1336                 printk(KERN_ERR "%s unusable with this kernel!\n", usbatm_driver_name);
1337                 return -EIO;
1338         }
1339
1340         if ((num_rcv_urbs > UDSL_MAX_RCV_URBS)
1341             || (num_snd_urbs > UDSL_MAX_SND_URBS)
1342             || (rcv_buf_bytes < 1)
1343             || (rcv_buf_bytes > UDSL_MAX_BUF_SIZE)
1344             || (snd_buf_bytes < 1)
1345             || (snd_buf_bytes > UDSL_MAX_BUF_SIZE))
1346                 return -EINVAL;
1347
1348         return 0;
1349 }
1350 module_init(usbatm_usb_init);
1351
1352 static void __exit usbatm_usb_exit(void)
1353 {
1354         dbg("%s", __func__);
1355 }
1356 module_exit(usbatm_usb_exit);
1357
1358 MODULE_AUTHOR(DRIVER_AUTHOR);
1359 MODULE_DESCRIPTION(DRIVER_DESC);
1360 MODULE_LICENSE("GPL");
1361 MODULE_VERSION(DRIVER_VERSION);
1362
1363 /************
1364 **  debug  **
1365 ************/
1366
1367 #ifdef VERBOSE_DEBUG
1368 static int usbatm_print_packet(const unsigned char *data, int len)
1369 {
1370         unsigned char buffer[256];
1371         int i = 0, j = 0;
1372
1373         for (i = 0; i < len;) {
1374                 buffer[0] = '\0';
1375                 sprintf(buffer, "%.3d :", i);
1376                 for (j = 0; (j < 16) && (i < len); j++, i++) {
1377                         sprintf(buffer, "%s %2.2x", buffer, data[i]);
1378                 }
1379                 dbg("%s", buffer);
1380         }
1381         return i;
1382 }
1383 #endif