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
  87static 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
  99static 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
 113static unsigned int num_rcv_urbs = UDSL_DEFAULT_RCV_URBS;
 114static unsigned int num_snd_urbs = UDSL_DEFAULT_SND_URBS;
 115static unsigned int rcv_buf_bytes = UDSL_DEFAULT_RCV_BUF_SIZE;
 116static unsigned int snd_buf_bytes = UDSL_DEFAULT_SND_BUF_SIZE;
 117
 118module_param(num_rcv_urbs, uint, S_IRUGO);
 119MODULE_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
 124module_param(num_snd_urbs, uint, S_IRUGO);
 125MODULE_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
 130module_param(rcv_buf_bytes, uint, S_IRUGO);
 131MODULE_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
 136module_param(snd_buf_bytes, uint, S_IRUGO);
 137MODULE_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
 145struct 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
 159struct 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
 170static void usbatm_atm_dev_close(struct atm_dev *atm_dev);
 171static int usbatm_atm_open(struct atm_vcc *vcc);
 172static void usbatm_atm_close(struct atm_vcc *vcc);
 173static int usbatm_atm_ioctl(struct atm_dev *atm_dev, unsigned int cmd, void __user *arg);
 174static int usbatm_atm_send(struct atm_vcc *vcc, struct sk_buff *skb);
 175static int usbatm_atm_proc_read(struct atm_dev *atm_dev, loff_t *pos, char *page);
 176
 177static 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
 192static 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
 198static 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
 211static 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
 228static 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
 258static 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
 295static 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
 306static 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
 424static 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
 469static 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
 529static 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
 582static 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
 633static 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
 657static 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
 707static 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
 717static void usbatm_get_instance(struct usbatm_data *instance)
 718{
 719	kref_get(&instance->refcount);
 720}
 721
 722static 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
 732static 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
 743static 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
 783static 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		atm_err(instance, "%s: no memory for vcc_data!\n", __func__);
 823		ret = -ENOMEM;
 824		goto fail;
 825	}
 826
 827	new->vcc = vcc;
 828	new->vpi = vpi;
 829	new->vci = vci;
 830
 831	new->sarb = alloc_skb(usbatm_pdu_length(vcc->qos.rxtp.max_sdu), GFP_KERNEL);
 832	if (!new->sarb) {
 833		atm_err(instance, "%s: no memory for SAR buffer!\n", __func__);
 834		ret = -ENOMEM;
 835		goto fail;
 836	}
 837
 838	vcc->dev_data = new;
 839
 840	tasklet_disable(&instance->rx_channel.tasklet);
 841	instance->cached_vcc = new;
 842	instance->cached_vpi = vpi;
 843	instance->cached_vci = vci;
 844	list_add(&new->list, &instance->vcc_list);
 845	tasklet_enable(&instance->rx_channel.tasklet);
 846
 847	set_bit(ATM_VF_ADDR, &vcc->flags);
 848	set_bit(ATM_VF_PARTIAL, &vcc->flags);
 849	set_bit(ATM_VF_READY, &vcc->flags);
 850
 851	mutex_unlock(&instance->serialize);
 852
 853	atm_dbg(instance, "%s: allocated vcc data 0x%p\n", __func__, new);
 854
 855	return 0;
 856
 857fail:
 858	kfree(new);
 859	mutex_unlock(&instance->serialize);
 860	return ret;
 861}
 862
 863static void usbatm_atm_close(struct atm_vcc *vcc)
 864{
 865	struct usbatm_data *instance = vcc->dev->dev_data;
 866	struct usbatm_vcc_data *vcc_data = vcc->dev_data;
 867
 868	if (!instance || !vcc_data)
 869		return;
 870
 871	usbatm_cancel_send(instance, vcc);
 872
 873	mutex_lock(&instance->serialize);	/* vs self, usbatm_atm_open, usbatm_usb_disconnect */
 874
 875	tasklet_disable(&instance->rx_channel.tasklet);
 876	if (instance->cached_vcc == vcc_data) {
 877		instance->cached_vcc = NULL;
 878		instance->cached_vpi = ATM_VPI_UNSPEC;
 879		instance->cached_vci = ATM_VCI_UNSPEC;
 880	}
 881	list_del(&vcc_data->list);
 882	tasklet_enable(&instance->rx_channel.tasklet);
 883
 884	kfree_skb(vcc_data->sarb);
 885	vcc_data->sarb = NULL;
 886
 887	kfree(vcc_data);
 888	vcc->dev_data = NULL;
 889
 890	vcc->vpi = ATM_VPI_UNSPEC;
 891	vcc->vci = ATM_VCI_UNSPEC;
 892	clear_bit(ATM_VF_READY, &vcc->flags);
 893	clear_bit(ATM_VF_PARTIAL, &vcc->flags);
 894	clear_bit(ATM_VF_ADDR, &vcc->flags);
 895
 896	mutex_unlock(&instance->serialize);
 897}
 898
 899static int usbatm_atm_ioctl(struct atm_dev *atm_dev, unsigned int cmd,
 900			  void __user *arg)
 901{
 902	struct usbatm_data *instance = atm_dev->dev_data;
 903
 904	if (!instance || instance->disconnected)
 905		return -ENODEV;
 906
 907	switch (cmd) {
 908	case ATM_QUERYLOOP:
 909		return put_user(ATM_LM_NONE, (int __user *)arg) ? -EFAULT : 0;
 910	default:
 911		return -ENOIOCTLCMD;
 912	}
 913}
 914
 915static int usbatm_atm_init(struct usbatm_data *instance)
 916{
 917	struct atm_dev *atm_dev;
 918	int ret, i;
 919
 920	/* ATM init.  The ATM initialization scheme suffers from an intrinsic race
 921	 * condition: callbacks we register can be executed at once, before we have
 922	 * initialized the struct atm_dev.  To protect against this, all callbacks
 923	 * abort if atm_dev->dev_data is NULL. */
 924	atm_dev = atm_dev_register(instance->driver_name,
 925				   &instance->usb_intf->dev, &usbatm_atm_devops,
 926				   -1, NULL);
 927	if (!atm_dev) {
 928		usb_err(instance, "%s: failed to register ATM device!\n", __func__);
 929		return -1;
 930	}
 931
 932	instance->atm_dev = atm_dev;
 933
 934	atm_dev->ci_range.vpi_bits = ATM_CI_MAX;
 935	atm_dev->ci_range.vci_bits = ATM_CI_MAX;
 936	atm_dev->signal = ATM_PHY_SIG_UNKNOWN;
 937
 938	/* temp init ATM device, set to 128kbit */
 939	atm_dev->link_rate = 128 * 1000 / 424;
 940
 941	if (instance->driver->atm_start && ((ret = instance->driver->atm_start(instance, atm_dev)) < 0)) {
 942		atm_err(instance, "%s: atm_start failed: %d!\n", __func__, ret);
 943		goto fail;
 944	}
 945
 946	usbatm_get_instance(instance);	/* dropped in usbatm_atm_dev_close */
 947
 948	/* ready for ATM callbacks */
 949	mb();
 950	atm_dev->dev_data = instance;
 951
 952	/* submit all rx URBs */
 953	for (i = 0; i < num_rcv_urbs; i++)
 954		usbatm_submit_urb(instance->urbs[i]);
 955
 956	return 0;
 957
 958 fail:
 959	instance->atm_dev = NULL;
 960	atm_dev_deregister(atm_dev); /* usbatm_atm_dev_close will eventually be called */
 961	return ret;
 962}
 963
 964
 965/**********
 966**  USB  **
 967**********/
 968
 969static int usbatm_do_heavy_init(void *arg)
 970{
 971	struct usbatm_data *instance = arg;
 972	int ret;
 973
 974	allow_signal(SIGTERM);
 975	complete(&instance->thread_started);
 976
 977	ret = instance->driver->heavy_init(instance, instance->usb_intf);
 978
 979	if (!ret)
 980		ret = usbatm_atm_init(instance);
 981
 982	mutex_lock(&instance->serialize);
 983	instance->thread = NULL;
 984	mutex_unlock(&instance->serialize);
 985
 986	complete_and_exit(&instance->thread_exited, ret);
 987}
 988
 989static int usbatm_heavy_init(struct usbatm_data *instance)
 990{
 991	struct task_struct *t;
 992
 993	t = kthread_create(usbatm_do_heavy_init, instance, "%s",
 994			instance->driver->driver_name);
 995	if (IS_ERR(t)) {
 996		usb_err(instance, "%s: failed to create kernel_thread (%ld)!\n",
 997				__func__, PTR_ERR(t));
 998		return PTR_ERR(t);
 999	}
1000
1001	instance->thread = t;
1002	wake_up_process(t);
1003	wait_for_completion(&instance->thread_started);
1004
1005	return 0;
1006}
1007
1008static void usbatm_tasklet_schedule(unsigned long data)
1009{
1010	tasklet_schedule((struct tasklet_struct *) data);
1011}
1012
1013static void usbatm_init_channel(struct usbatm_channel *channel)
1014{
1015	spin_lock_init(&channel->lock);
1016	INIT_LIST_HEAD(&channel->list);
1017	channel->delay.function = usbatm_tasklet_schedule;
1018	channel->delay.data = (unsigned long) &channel->tasklet;
1019	init_timer(&channel->delay);
1020}
1021
1022int usbatm_usb_probe(struct usb_interface *intf, const struct usb_device_id *id,
1023		     struct usbatm_driver *driver)
1024{
1025	struct device *dev = &intf->dev;
1026	struct usb_device *usb_dev = interface_to_usbdev(intf);
1027	struct usbatm_data *instance;
1028	char *buf;
1029	int error = -ENOMEM;
1030	int i, length;
1031	unsigned int maxpacket, num_packets;
1032
1033	/* instance init */
1034	instance = kzalloc(sizeof(*instance) + sizeof(struct urb *) * (num_rcv_urbs + num_snd_urbs), GFP_KERNEL);
1035	if (!instance) {
1036		dev_err(dev, "%s: no memory for instance data!\n", __func__);
1037		return -ENOMEM;
1038	}
1039
1040	/* public fields */
1041
1042	instance->driver = driver;
1043	strlcpy(instance->driver_name, driver->driver_name,
1044		sizeof(instance->driver_name));
1045
1046	instance->usb_dev = usb_dev;
1047	instance->usb_intf = intf;
1048
1049	buf = instance->description;
1050	length = sizeof(instance->description);
1051
1052	if ((i = usb_string(usb_dev, usb_dev->descriptor.iProduct, buf, length)) < 0)
1053		goto bind;
1054
1055	buf += i;
1056	length -= i;
1057
1058	i = scnprintf(buf, length, " (");
1059	buf += i;
1060	length -= i;
1061
1062	if (length <= 0 || (i = usb_make_path(usb_dev, buf, length)) < 0)
1063		goto bind;
1064
1065	buf += i;
1066	length -= i;
1067
1068	snprintf(buf, length, ")");
1069
1070 bind:
1071	if (driver->bind && (error = driver->bind(instance, intf, id)) < 0) {
1072			dev_err(dev, "%s: bind failed: %d!\n", __func__, error);
1073			goto fail_free;
1074	}
1075
1076	/* private fields */
1077
1078	kref_init(&instance->refcount);		/* dropped in usbatm_usb_disconnect */
1079	mutex_init(&instance->serialize);
1080
1081	instance->thread = NULL;
1082	init_completion(&instance->thread_started);
1083	init_completion(&instance->thread_exited);
1084
1085	INIT_LIST_HEAD(&instance->vcc_list);
1086	skb_queue_head_init(&instance->sndqueue);
1087
1088	usbatm_init_channel(&instance->rx_channel);
1089	usbatm_init_channel(&instance->tx_channel);
1090	tasklet_init(&instance->rx_channel.tasklet, usbatm_rx_process, (unsigned long)instance);
1091	tasklet_init(&instance->tx_channel.tasklet, usbatm_tx_process, (unsigned long)instance);
1092	instance->rx_channel.stride = ATM_CELL_SIZE + driver->rx_padding;
1093	instance->tx_channel.stride = ATM_CELL_SIZE + driver->tx_padding;
1094	instance->rx_channel.usbatm = instance->tx_channel.usbatm = instance;
1095
1096	if ((instance->flags & UDSL_USE_ISOC) && driver->isoc_in)
1097		instance->rx_channel.endpoint = usb_rcvisocpipe(usb_dev, driver->isoc_in);
1098	else
1099		instance->rx_channel.endpoint = usb_rcvbulkpipe(usb_dev, driver->bulk_in);
1100
1101	instance->tx_channel.endpoint = usb_sndbulkpipe(usb_dev, driver->bulk_out);
1102
1103	/* tx buffer size must be a positive multiple of the stride */
1104	instance->tx_channel.buf_size = max(instance->tx_channel.stride,
1105			snd_buf_bytes - (snd_buf_bytes % instance->tx_channel.stride));
1106
1107	/* rx buffer size must be a positive multiple of the endpoint maxpacket */
1108	maxpacket = usb_maxpacket(usb_dev, instance->rx_channel.endpoint, 0);
1109
1110	if ((maxpacket < 1) || (maxpacket > UDSL_MAX_BUF_SIZE)) {
1111		dev_err(dev, "%s: invalid endpoint %02x!\n", __func__,
1112				usb_pipeendpoint(instance->rx_channel.endpoint));
1113		error = -EINVAL;
1114		goto fail_unbind;
1115	}
1116
1117	num_packets = max(1U, (rcv_buf_bytes + maxpacket / 2) / maxpacket); /* round */
1118
1119	if (num_packets * maxpacket > UDSL_MAX_BUF_SIZE)
1120		num_packets--;
1121
1122	instance->rx_channel.buf_size = num_packets * maxpacket;
1123	instance->rx_channel.packet_size = maxpacket;
1124
1125	for (i = 0; i < 2; i++) {
1126		struct usbatm_channel *channel = i ?
1127			&instance->tx_channel : &instance->rx_channel;
1128
1129		dev_dbg(dev, "%s: using %d byte buffer for %s channel 0x%p\n",
1130			__func__, channel->buf_size, i ? "tx" : "rx", channel);
1131	}
1132
1133	/* initialize urbs */
1134
1135	for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) {
1136		u8 *buffer;
1137		struct usbatm_channel *channel = i < num_rcv_urbs ?
1138			&instance->rx_channel : &instance->tx_channel;
1139		struct urb *urb;
1140		unsigned int iso_packets = usb_pipeisoc(channel->endpoint) ? channel->buf_size / channel->packet_size : 0;
1141
1142		urb = usb_alloc_urb(iso_packets, GFP_KERNEL);
1143		if (!urb) {
1144			dev_err(dev, "%s: no memory for urb %d!\n", __func__, i);
1145			error = -ENOMEM;
1146			goto fail_unbind;
1147		}
1148
1149		instance->urbs[i] = urb;
1150
1151		/* zero the tx padding to avoid leaking information */
1152		buffer = kzalloc(channel->buf_size, GFP_KERNEL);
1153		if (!buffer) {
1154			dev_err(dev, "%s: no memory for buffer %d!\n", __func__, i);
1155			error = -ENOMEM;
1156			goto fail_unbind;
1157		}
1158
1159		usb_fill_bulk_urb(urb, instance->usb_dev, channel->endpoint,
1160				  buffer, channel->buf_size, usbatm_complete, channel);
1161		if (iso_packets) {
1162			int j;
1163			urb->interval = 1;
1164			urb->transfer_flags = URB_ISO_ASAP;
1165			urb->number_of_packets = iso_packets;
1166			for (j = 0; j < iso_packets; j++) {
1167				urb->iso_frame_desc[j].offset = channel->packet_size * j;
1168				urb->iso_frame_desc[j].length = channel->packet_size;
1169			}
1170		}
1171
1172		/* put all tx URBs on the list of spares */
1173		if (i >= num_rcv_urbs)
1174			list_add_tail(&urb->urb_list, &channel->list);
1175
1176		vdbg(&intf->dev, "%s: alloced buffer 0x%p buf size %u urb 0x%p",
1177		     __func__, urb->transfer_buffer, urb->transfer_buffer_length, urb);
1178	}
1179
1180	instance->cached_vpi = ATM_VPI_UNSPEC;
1181	instance->cached_vci = ATM_VCI_UNSPEC;
1182	instance->cell_buf = kmalloc(instance->rx_channel.stride, GFP_KERNEL);
1183
1184	if (!instance->cell_buf) {
1185		dev_err(dev, "%s: no memory for cell buffer!\n", __func__);
1186		error = -ENOMEM;
1187		goto fail_unbind;
1188	}
1189
1190	if (!(instance->flags & UDSL_SKIP_HEAVY_INIT) && driver->heavy_init) {
1191		error = usbatm_heavy_init(instance);
1192	} else {
1193		complete(&instance->thread_exited);	/* pretend that heavy_init was run */
1194		error = usbatm_atm_init(instance);
1195	}
1196
1197	if (error < 0)
1198		goto fail_unbind;
1199
1200	usb_get_dev(usb_dev);
1201	usb_set_intfdata(intf, instance);
1202
1203	return 0;
1204
1205 fail_unbind:
1206	if (instance->driver->unbind)
1207		instance->driver->unbind(instance, intf);
1208 fail_free:
1209	kfree(instance->cell_buf);
1210
1211	for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) {
1212		if (instance->urbs[i])
1213			kfree(instance->urbs[i]->transfer_buffer);
1214		usb_free_urb(instance->urbs[i]);
1215	}
1216
1217	kfree(instance);
1218
1219	return error;
1220}
1221EXPORT_SYMBOL_GPL(usbatm_usb_probe);
1222
1223void usbatm_usb_disconnect(struct usb_interface *intf)
1224{
1225	struct device *dev = &intf->dev;
1226	struct usbatm_data *instance = usb_get_intfdata(intf);
1227	struct usbatm_vcc_data *vcc_data;
1228	int i;
1229
1230	if (!instance) {
1231		dev_dbg(dev, "%s: NULL instance!\n", __func__);
1232		return;
1233	}
1234
1235	usb_set_intfdata(intf, NULL);
1236
1237	mutex_lock(&instance->serialize);
1238	instance->disconnected = 1;
1239	if (instance->thread != NULL)
1240		send_sig(SIGTERM, instance->thread, 1);
1241	mutex_unlock(&instance->serialize);
1242
1243	wait_for_completion(&instance->thread_exited);
1244
1245	mutex_lock(&instance->serialize);
1246	list_for_each_entry(vcc_data, &instance->vcc_list, list)
1247		vcc_release_async(vcc_data->vcc, -EPIPE);
1248	mutex_unlock(&instance->serialize);
1249
1250	tasklet_disable(&instance->rx_channel.tasklet);
1251	tasklet_disable(&instance->tx_channel.tasklet);
1252
1253	for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++)
1254		usb_kill_urb(instance->urbs[i]);
1255
1256	del_timer_sync(&instance->rx_channel.delay);
1257	del_timer_sync(&instance->tx_channel.delay);
1258
1259	/* turn usbatm_[rt]x_process into something close to a no-op */
1260	/* no need to take the spinlock */
1261	INIT_LIST_HEAD(&instance->rx_channel.list);
1262	INIT_LIST_HEAD(&instance->tx_channel.list);
1263
1264	tasklet_enable(&instance->rx_channel.tasklet);
1265	tasklet_enable(&instance->tx_channel.tasklet);
1266
1267	if (instance->atm_dev && instance->driver->atm_stop)
1268		instance->driver->atm_stop(instance, instance->atm_dev);
1269
1270	if (instance->driver->unbind)
1271		instance->driver->unbind(instance, intf);
1272
1273	instance->driver_data = NULL;
1274
1275	for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) {
1276		kfree(instance->urbs[i]->transfer_buffer);
1277		usb_free_urb(instance->urbs[i]);
1278	}
1279
1280	kfree(instance->cell_buf);
1281
1282	/* ATM finalize */
1283	if (instance->atm_dev) {
1284		atm_dev_deregister(instance->atm_dev);
1285		instance->atm_dev = NULL;
1286	}
1287
1288	usbatm_put_instance(instance);	/* taken in usbatm_usb_probe */
1289}
1290EXPORT_SYMBOL_GPL(usbatm_usb_disconnect);
1291
1292
1293/***********
1294**  init  **
1295***********/
1296
1297static int __init usbatm_usb_init(void)
1298{
1299	if (sizeof(struct usbatm_control) > FIELD_SIZEOF(struct sk_buff, cb)) {
1300		printk(KERN_ERR "%s unusable with this kernel!\n", usbatm_driver_name);
1301		return -EIO;
1302	}
1303
1304	if ((num_rcv_urbs > UDSL_MAX_RCV_URBS)
1305	    || (num_snd_urbs > UDSL_MAX_SND_URBS)
1306	    || (rcv_buf_bytes < 1)
1307	    || (rcv_buf_bytes > UDSL_MAX_BUF_SIZE)
1308	    || (snd_buf_bytes < 1)
1309	    || (snd_buf_bytes > UDSL_MAX_BUF_SIZE))
1310		return -EINVAL;
1311
1312	return 0;
1313}
1314module_init(usbatm_usb_init);
1315
1316static void __exit usbatm_usb_exit(void)
1317{
1318}
1319module_exit(usbatm_usb_exit);
1320
1321MODULE_AUTHOR(DRIVER_AUTHOR);
1322MODULE_DESCRIPTION(DRIVER_DESC);
1323MODULE_LICENSE("GPL");
1324MODULE_VERSION(DRIVER_VERSION);
1325
1326/************
1327**  debug  **
1328************/
1329
1330#ifdef VERBOSE_DEBUG
1331static int usbatm_print_packet(struct usbatm_data *instance,
1332			       const unsigned char *data, int len)
1333{
1334	unsigned char buffer[256];
1335	int i = 0, j = 0;
1336
1337	for (i = 0; i < len;) {
1338		buffer[0] = '\0';
1339		sprintf(buffer, "%.3d :", i);
1340		for (j = 0; (j < 16) && (i < len); j++, i++)
1341			sprintf(buffer, "%s %2.2x", buffer, data[i]);
1342		dev_dbg(&instance->usb_intf->dev, "%s", buffer);
1343	}
1344	return i;
1345}
1346#endif