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