1 // SPDX-License-Identifier: GPL-2.0+ 2 /****************************************************************************** 3 * usbatm.c - Generic USB xDSL driver core 4 * 5 * Copyright (C) 2001, Alcatel 6 * Copyright (C) 2003, Duncan Sands, SolNegro, Josep Comas 7 * Copyright (C) 2004, David Woodhouse, Roman Kagan 8 ******************************************************************************/ 9 10 /* 11 * Written by Johan Verrept, Duncan Sands (duncan.sands@free.fr) and David Woodhouse 12 * 13 * 1.7+: - See the check-in logs 14 * 15 * 1.6: - No longer opens a connection if the firmware is not loaded 16 * - Added support for the speedtouch 330 17 * - Removed the limit on the number of devices 18 * - Module now autoloads on device plugin 19 * - Merged relevant parts of sarlib 20 * - Replaced the kernel thread with a tasklet 21 * - New packet transmission code 22 * - Changed proc file contents 23 * - Fixed all known SMP races 24 * - Many fixes and cleanups 25 * - Various fixes by Oliver Neukum (oliver@neukum.name) 26 * 27 * 1.5A: - Version for inclusion in 2.5 series kernel 28 * - Modifications by Richard Purdie (rpurdie@rpsys.net) 29 * - made compatible with kernel 2.5.6 onwards by changing 30 * usbatm_usb_send_data_context->urb to a pointer and adding code 31 * to alloc and free it 32 * - remove_wait_queue() added to usbatm_atm_processqueue_thread() 33 * 34 * 1.5: - fixed memory leak when atmsar_decode_aal5 returned NULL. 35 * (reported by stephen.robinson@zen.co.uk) 36 * 37 * 1.4: - changed the spin_lock() under interrupt to spin_lock_irqsave() 38 * - unlink all active send urbs of a vcc that is being closed. 39 * 40 * 1.3.1: - added the version number 41 * 42 * 1.3: - Added multiple send urb support 43 * - fixed memory leak and vcc->tx_inuse starvation bug 44 * when not enough memory left in vcc. 45 * 46 * 1.2: - Fixed race condition in usbatm_usb_send_data() 47 * 1.1: - Turned off packet debugging 48 * 49 */ 50 51 #include "usbatm.h" 52 53 #include <linux/uaccess.h> 54 #include <linux/crc32.h> 55 #include <linux/errno.h> 56 #include <linux/init.h> 57 #include <linux/interrupt.h> 58 #include <linux/kernel.h> 59 #include <linux/module.h> 60 #include <linux/moduleparam.h> 61 #include <linux/netdevice.h> 62 #include <linux/proc_fs.h> 63 #include <linux/sched/signal.h> 64 #include <linux/signal.h> 65 #include <linux/slab.h> 66 #include <linux/stat.h> 67 #include <linux/timer.h> 68 #include <linux/wait.h> 69 #include <linux/kthread.h> 70 #include <linux/ratelimit.h> 71 72 #ifdef VERBOSE_DEBUG 73 static int usbatm_print_packet(struct usbatm_data *instance, const unsigned char *data, int len); 74 #define PACKETDEBUG(arg...) usbatm_print_packet(arg) 75 #define vdbg(arg...) dev_dbg(arg) 76 #else 77 #define PACKETDEBUG(arg...) 78 #define vdbg(arg...) 79 #endif 80 81 #define DRIVER_AUTHOR "Johan Verrept, Duncan Sands <duncan.sands@free.fr>" 82 #define DRIVER_DESC "Generic USB ATM/DSL I/O" 83 84 static const char usbatm_driver_name[] = "usbatm"; 85 86 #define UDSL_MAX_RCV_URBS 16 87 #define UDSL_MAX_SND_URBS 16 88 #define UDSL_MAX_BUF_SIZE 65536 89 #define UDSL_DEFAULT_RCV_URBS 4 90 #define UDSL_DEFAULT_SND_URBS 4 91 #define UDSL_DEFAULT_RCV_BUF_SIZE 3392 /* 64 * ATM_CELL_SIZE */ 92 #define UDSL_DEFAULT_SND_BUF_SIZE 3392 /* 64 * ATM_CELL_SIZE */ 93 94 #define ATM_CELL_HEADER (ATM_CELL_SIZE - ATM_CELL_PAYLOAD) 95 96 #define THROTTLE_MSECS 100 /* delay to recover processing after urb submission fails */ 97 98 static unsigned int num_rcv_urbs = UDSL_DEFAULT_RCV_URBS; 99 static unsigned int num_snd_urbs = UDSL_DEFAULT_SND_URBS; 100 static unsigned int rcv_buf_bytes = UDSL_DEFAULT_RCV_BUF_SIZE; 101 static unsigned int snd_buf_bytes = UDSL_DEFAULT_SND_BUF_SIZE; 102 103 module_param(num_rcv_urbs, uint, S_IRUGO); 104 MODULE_PARM_DESC(num_rcv_urbs, 105 "Number of urbs used for reception (range: 0-" 106 __MODULE_STRING(UDSL_MAX_RCV_URBS) ", default: " 107 __MODULE_STRING(UDSL_DEFAULT_RCV_URBS) ")"); 108 109 module_param(num_snd_urbs, uint, S_IRUGO); 110 MODULE_PARM_DESC(num_snd_urbs, 111 "Number of urbs used for transmission (range: 0-" 112 __MODULE_STRING(UDSL_MAX_SND_URBS) ", default: " 113 __MODULE_STRING(UDSL_DEFAULT_SND_URBS) ")"); 114 115 module_param(rcv_buf_bytes, uint, S_IRUGO); 116 MODULE_PARM_DESC(rcv_buf_bytes, 117 "Size of the buffers used for reception, in bytes (range: 1-" 118 __MODULE_STRING(UDSL_MAX_BUF_SIZE) ", default: " 119 __MODULE_STRING(UDSL_DEFAULT_RCV_BUF_SIZE) ")"); 120 121 module_param(snd_buf_bytes, uint, S_IRUGO); 122 MODULE_PARM_DESC(snd_buf_bytes, 123 "Size of the buffers used for transmission, in bytes (range: 1-" 124 __MODULE_STRING(UDSL_MAX_BUF_SIZE) ", default: " 125 __MODULE_STRING(UDSL_DEFAULT_SND_BUF_SIZE) ")"); 126 127 128 /* receive */ 129 130 struct usbatm_vcc_data { 131 /* vpi/vci lookup */ 132 struct list_head list; 133 short vpi; 134 int vci; 135 struct atm_vcc *vcc; 136 137 /* raw cell reassembly */ 138 struct sk_buff *sarb; 139 }; 140 141 142 /* send */ 143 144 struct usbatm_control { 145 struct atm_skb_data atm; 146 u32 len; 147 u32 crc; 148 }; 149 150 #define UDSL_SKB(x) ((struct usbatm_control *)(x)->cb) 151 152 153 /* ATM */ 154 155 static void usbatm_atm_dev_close(struct atm_dev *atm_dev); 156 static int usbatm_atm_open(struct atm_vcc *vcc); 157 static void usbatm_atm_close(struct atm_vcc *vcc); 158 static int usbatm_atm_ioctl(struct atm_dev *atm_dev, unsigned int cmd, void __user *arg); 159 static int usbatm_atm_send(struct atm_vcc *vcc, struct sk_buff *skb); 160 static int usbatm_atm_proc_read(struct atm_dev *atm_dev, loff_t *pos, char *page); 161 162 static const struct atmdev_ops usbatm_atm_devops = { 163 .dev_close = usbatm_atm_dev_close, 164 .open = usbatm_atm_open, 165 .close = usbatm_atm_close, 166 .ioctl = usbatm_atm_ioctl, 167 .send = usbatm_atm_send, 168 .proc_read = usbatm_atm_proc_read, 169 .owner = THIS_MODULE, 170 }; 171 172 173 /*********** 174 ** misc ** 175 ***********/ 176 177 static inline unsigned int usbatm_pdu_length(unsigned int length) 178 { 179 length += ATM_CELL_PAYLOAD - 1 + ATM_AAL5_TRAILER; 180 return length - length % ATM_CELL_PAYLOAD; 181 } 182 183 static inline void usbatm_pop(struct atm_vcc *vcc, struct sk_buff *skb) 184 { 185 if (vcc->pop) 186 vcc->pop(vcc, skb); 187 else 188 dev_kfree_skb_any(skb); 189 } 190 191 192 /*********** 193 ** urbs ** 194 ************/ 195 196 static struct urb *usbatm_pop_urb(struct usbatm_channel *channel) 197 { 198 struct urb *urb; 199 200 spin_lock_irq(&channel->lock); 201 if (list_empty(&channel->list)) { 202 spin_unlock_irq(&channel->lock); 203 return NULL; 204 } 205 206 urb = list_entry(channel->list.next, struct urb, urb_list); 207 list_del(&urb->urb_list); 208 spin_unlock_irq(&channel->lock); 209 210 return urb; 211 } 212 213 static int usbatm_submit_urb(struct urb *urb) 214 { 215 struct usbatm_channel *channel = urb->context; 216 int ret; 217 218 /* vdbg("%s: submitting urb 0x%p, size %u", 219 __func__, urb, urb->transfer_buffer_length); */ 220 221 ret = usb_submit_urb(urb, GFP_ATOMIC); 222 if (ret) { 223 if (printk_ratelimit()) 224 atm_warn(channel->usbatm, "%s: urb 0x%p submission failed (%d)!\n", 225 __func__, urb, ret); 226 227 /* consider all errors transient and return the buffer back to the queue */ 228 urb->status = -EAGAIN; 229 spin_lock_irq(&channel->lock); 230 231 /* must add to the front when sending; doesn't matter when receiving */ 232 list_add(&urb->urb_list, &channel->list); 233 234 spin_unlock_irq(&channel->lock); 235 236 /* make sure the channel doesn't stall */ 237 mod_timer(&channel->delay, jiffies + msecs_to_jiffies(THROTTLE_MSECS)); 238 } 239 240 return ret; 241 } 242 243 static void usbatm_complete(struct urb *urb) 244 { 245 struct usbatm_channel *channel = urb->context; 246 unsigned long flags; 247 int status = urb->status; 248 249 /* vdbg("%s: urb 0x%p, status %d, actual_length %d", 250 __func__, urb, status, urb->actual_length); */ 251 252 /* Can be invoked from task context, protect against interrupts */ 253 spin_lock_irqsave(&channel->lock, flags); 254 255 /* must add to the back when receiving; doesn't matter when sending */ 256 list_add_tail(&urb->urb_list, &channel->list); 257 258 spin_unlock_irqrestore(&channel->lock, flags); 259 260 if (unlikely(status) && 261 (!(channel->usbatm->flags & UDSL_IGNORE_EILSEQ) || 262 status != -EILSEQ)) { 263 if (status == -ESHUTDOWN) 264 return; 265 266 if (printk_ratelimit()) 267 atm_warn(channel->usbatm, "%s: urb 0x%p failed (%d)!\n", 268 __func__, urb, status); 269 /* throttle processing in case of an error */ 270 mod_timer(&channel->delay, jiffies + msecs_to_jiffies(THROTTLE_MSECS)); 271 } else 272 tasklet_schedule(&channel->tasklet); 273 } 274 275 276 /************* 277 ** decode ** 278 *************/ 279 280 static inline struct usbatm_vcc_data *usbatm_find_vcc(struct usbatm_data *instance, 281 short vpi, int vci) 282 { 283 struct usbatm_vcc_data *vcc_data; 284 285 list_for_each_entry(vcc_data, &instance->vcc_list, list) 286 if ((vcc_data->vci == vci) && (vcc_data->vpi == vpi)) 287 return vcc_data; 288 return NULL; 289 } 290 291 static void usbatm_extract_one_cell(struct usbatm_data *instance, unsigned char *source) 292 { 293 struct atm_vcc *vcc; 294 struct sk_buff *sarb; 295 short vpi = ((source[0] & 0x0f) << 4) | (source[1] >> 4); 296 int vci = ((source[1] & 0x0f) << 12) | (source[2] << 4) | (source[3] >> 4); 297 u8 pti = ((source[3] & 0xe) >> 1); 298 299 if ((vci != instance->cached_vci) || (vpi != instance->cached_vpi)) { 300 instance->cached_vpi = vpi; 301 instance->cached_vci = vci; 302 303 instance->cached_vcc = usbatm_find_vcc(instance, vpi, vci); 304 305 if (!instance->cached_vcc) 306 atm_rldbg(instance, "%s: unknown vpi/vci (%hd/%d)!\n", __func__, vpi, vci); 307 } 308 309 if (!instance->cached_vcc) 310 return; 311 312 vcc = instance->cached_vcc->vcc; 313 314 /* OAM F5 end-to-end */ 315 if (pti == ATM_PTI_E2EF5) { 316 if (printk_ratelimit()) 317 atm_warn(instance, "%s: OAM not supported (vpi %d, vci %d)!\n", 318 __func__, vpi, vci); 319 atomic_inc(&vcc->stats->rx_err); 320 return; 321 } 322 323 sarb = instance->cached_vcc->sarb; 324 325 if (sarb->tail + ATM_CELL_PAYLOAD > sarb->end) { 326 atm_rldbg(instance, "%s: buffer overrun (sarb->len %u, vcc: 0x%p)!\n", 327 __func__, sarb->len, vcc); 328 /* discard cells already received */ 329 skb_trim(sarb, 0); 330 } 331 332 memcpy(skb_tail_pointer(sarb), source + ATM_CELL_HEADER, ATM_CELL_PAYLOAD); 333 __skb_put(sarb, ATM_CELL_PAYLOAD); 334 335 if (pti & 1) { 336 struct sk_buff *skb; 337 unsigned int length; 338 unsigned int pdu_length; 339 340 length = (source[ATM_CELL_SIZE - 6] << 8) + source[ATM_CELL_SIZE - 5]; 341 342 /* guard against overflow */ 343 if (length > ATM_MAX_AAL5_PDU) { 344 atm_rldbg(instance, "%s: bogus length %u (vcc: 0x%p)!\n", 345 __func__, length, vcc); 346 atomic_inc(&vcc->stats->rx_err); 347 goto out; 348 } 349 350 pdu_length = usbatm_pdu_length(length); 351 352 if (sarb->len < pdu_length) { 353 atm_rldbg(instance, "%s: bogus pdu_length %u (sarb->len: %u, vcc: 0x%p)!\n", 354 __func__, pdu_length, sarb->len, vcc); 355 atomic_inc(&vcc->stats->rx_err); 356 goto out; 357 } 358 359 if (crc32_be(~0, skb_tail_pointer(sarb) - pdu_length, pdu_length) != 0xc704dd7b) { 360 atm_rldbg(instance, "%s: packet failed crc check (vcc: 0x%p)!\n", 361 __func__, vcc); 362 atomic_inc(&vcc->stats->rx_err); 363 goto out; 364 } 365 366 vdbg(&instance->usb_intf->dev, 367 "%s: got packet (length: %u, pdu_length: %u, vcc: 0x%p)", 368 __func__, length, pdu_length, vcc); 369 370 skb = dev_alloc_skb(length); 371 if (!skb) { 372 if (printk_ratelimit()) 373 atm_err(instance, "%s: no memory for skb (length: %u)!\n", 374 __func__, length); 375 atomic_inc(&vcc->stats->rx_drop); 376 goto out; 377 } 378 379 vdbg(&instance->usb_intf->dev, 380 "%s: allocated new sk_buff (skb: 0x%p, skb->truesize: %u)", 381 __func__, skb, skb->truesize); 382 383 if (!atm_charge(vcc, skb->truesize)) { 384 atm_rldbg(instance, "%s: failed atm_charge (skb->truesize: %u)!\n", 385 __func__, skb->truesize); 386 dev_kfree_skb_any(skb); 387 goto out; /* atm_charge increments rx_drop */ 388 } 389 390 skb_copy_to_linear_data(skb, 391 skb_tail_pointer(sarb) - pdu_length, 392 length); 393 __skb_put(skb, length); 394 395 vdbg(&instance->usb_intf->dev, 396 "%s: sending skb 0x%p, skb->len %u, skb->truesize %u", 397 __func__, skb, skb->len, skb->truesize); 398 399 PACKETDEBUG(instance, skb->data, skb->len); 400 401 vcc->push(vcc, skb); 402 403 atomic_inc(&vcc->stats->rx); 404 out: 405 skb_trim(sarb, 0); 406 } 407 } 408 409 static void usbatm_extract_cells(struct usbatm_data *instance, 410 unsigned char *source, unsigned int avail_data) 411 { 412 unsigned int stride = instance->rx_channel.stride; 413 unsigned int buf_usage = instance->buf_usage; 414 415 /* extract cells from incoming data, taking into account that 416 * the length of avail data may not be a multiple of stride */ 417 418 if (buf_usage > 0) { 419 /* we have a partially received atm cell */ 420 unsigned char *cell_buf = instance->cell_buf; 421 unsigned int space_left = stride - buf_usage; 422 423 if (avail_data >= space_left) { 424 /* add new data and process cell */ 425 memcpy(cell_buf + buf_usage, source, space_left); 426 source += space_left; 427 avail_data -= space_left; 428 usbatm_extract_one_cell(instance, cell_buf); 429 instance->buf_usage = 0; 430 } else { 431 /* not enough data to fill the cell */ 432 memcpy(cell_buf + buf_usage, source, avail_data); 433 instance->buf_usage = buf_usage + avail_data; 434 return; 435 } 436 } 437 438 for (; avail_data >= stride; avail_data -= stride, source += stride) 439 usbatm_extract_one_cell(instance, source); 440 441 if (avail_data > 0) { 442 /* length was not a multiple of stride - 443 * save remaining data for next call */ 444 memcpy(instance->cell_buf, source, avail_data); 445 instance->buf_usage = avail_data; 446 } 447 } 448 449 450 /************* 451 ** encode ** 452 *************/ 453 454 static unsigned int usbatm_write_cells(struct usbatm_data *instance, 455 struct sk_buff *skb, 456 u8 *target, unsigned int avail_space) 457 { 458 struct usbatm_control *ctrl = UDSL_SKB(skb); 459 struct atm_vcc *vcc = ctrl->atm.vcc; 460 unsigned int bytes_written; 461 unsigned int stride = instance->tx_channel.stride; 462 463 for (bytes_written = 0; bytes_written < avail_space && ctrl->len; 464 bytes_written += stride, target += stride) { 465 unsigned int data_len = min_t(unsigned int, skb->len, ATM_CELL_PAYLOAD); 466 unsigned int left = ATM_CELL_PAYLOAD - data_len; 467 u8 *ptr = target; 468 469 ptr[0] = vcc->vpi >> 4; 470 ptr[1] = (vcc->vpi << 4) | (vcc->vci >> 12); 471 ptr[2] = vcc->vci >> 4; 472 ptr[3] = vcc->vci << 4; 473 ptr[4] = 0xec; 474 ptr += ATM_CELL_HEADER; 475 476 skb_copy_from_linear_data(skb, ptr, data_len); 477 ptr += data_len; 478 __skb_pull(skb, data_len); 479 480 if (!left) 481 continue; 482 483 memset(ptr, 0, left); 484 485 if (left >= ATM_AAL5_TRAILER) { /* trailer will go in this cell */ 486 u8 *trailer = target + ATM_CELL_SIZE - ATM_AAL5_TRAILER; 487 /* trailer[0] = 0; UU = 0 */ 488 /* trailer[1] = 0; CPI = 0 */ 489 trailer[2] = ctrl->len >> 8; 490 trailer[3] = ctrl->len; 491 492 ctrl->crc = ~crc32_be(ctrl->crc, ptr, left - 4); 493 494 trailer[4] = ctrl->crc >> 24; 495 trailer[5] = ctrl->crc >> 16; 496 trailer[6] = ctrl->crc >> 8; 497 trailer[7] = ctrl->crc; 498 499 target[3] |= 0x2; /* adjust PTI */ 500 501 ctrl->len = 0; /* tag this skb finished */ 502 } else 503 ctrl->crc = crc32_be(ctrl->crc, ptr, left); 504 } 505 506 return bytes_written; 507 } 508 509 510 /************** 511 ** receive ** 512 **************/ 513 514 static void usbatm_rx_process(struct tasklet_struct *t) 515 { 516 struct usbatm_data *instance = from_tasklet(instance, t, 517 rx_channel.tasklet); 518 struct urb *urb; 519 520 while ((urb = usbatm_pop_urb(&instance->rx_channel))) { 521 vdbg(&instance->usb_intf->dev, 522 "%s: processing urb 0x%p", __func__, urb); 523 524 if (usb_pipeisoc(urb->pipe)) { 525 unsigned char *merge_start = NULL; 526 unsigned int merge_length = 0; 527 const unsigned int packet_size = instance->rx_channel.packet_size; 528 int i; 529 530 for (i = 0; i < urb->number_of_packets; i++) { 531 if (!urb->iso_frame_desc[i].status) { 532 unsigned int actual_length = urb->iso_frame_desc[i].actual_length; 533 534 if (!merge_length) 535 merge_start = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset; 536 merge_length += actual_length; 537 if (merge_length && (actual_length < packet_size)) { 538 usbatm_extract_cells(instance, merge_start, merge_length); 539 merge_length = 0; 540 } 541 } else { 542 atm_rldbg(instance, "%s: status %d in frame %d!\n", __func__, urb->status, i); 543 if (merge_length) 544 usbatm_extract_cells(instance, merge_start, merge_length); 545 merge_length = 0; 546 instance->buf_usage = 0; 547 } 548 } 549 550 if (merge_length) 551 usbatm_extract_cells(instance, merge_start, merge_length); 552 } else 553 if (!urb->status) 554 usbatm_extract_cells(instance, urb->transfer_buffer, urb->actual_length); 555 else 556 instance->buf_usage = 0; 557 558 if (usbatm_submit_urb(urb)) 559 return; 560 } 561 } 562 563 564 /*********** 565 ** send ** 566 ***********/ 567 568 static void usbatm_tx_process(struct tasklet_struct *t) 569 { 570 struct usbatm_data *instance = from_tasklet(instance, t, 571 tx_channel.tasklet); 572 struct sk_buff *skb = instance->current_skb; 573 struct urb *urb = NULL; 574 const unsigned int buf_size = instance->tx_channel.buf_size; 575 unsigned int bytes_written = 0; 576 u8 *buffer = NULL; 577 578 if (!skb) 579 skb = skb_dequeue(&instance->sndqueue); 580 581 while (skb) { 582 if (!urb) { 583 urb = usbatm_pop_urb(&instance->tx_channel); 584 if (!urb) 585 break; /* no more senders */ 586 buffer = urb->transfer_buffer; 587 bytes_written = (urb->status == -EAGAIN) ? 588 urb->transfer_buffer_length : 0; 589 } 590 591 bytes_written += usbatm_write_cells(instance, skb, 592 buffer + bytes_written, 593 buf_size - bytes_written); 594 595 vdbg(&instance->usb_intf->dev, 596 "%s: wrote %u bytes from skb 0x%p to urb 0x%p", 597 __func__, bytes_written, skb, urb); 598 599 if (!UDSL_SKB(skb)->len) { 600 struct atm_vcc *vcc = UDSL_SKB(skb)->atm.vcc; 601 602 usbatm_pop(vcc, skb); 603 atomic_inc(&vcc->stats->tx); 604 605 skb = skb_dequeue(&instance->sndqueue); 606 } 607 608 if (bytes_written == buf_size || (!skb && bytes_written)) { 609 urb->transfer_buffer_length = bytes_written; 610 611 if (usbatm_submit_urb(urb)) 612 break; 613 urb = NULL; 614 } 615 } 616 617 instance->current_skb = skb; 618 } 619 620 static void usbatm_cancel_send(struct usbatm_data *instance, 621 struct atm_vcc *vcc) 622 { 623 struct sk_buff *skb, *n; 624 625 spin_lock_irq(&instance->sndqueue.lock); 626 skb_queue_walk_safe(&instance->sndqueue, skb, n) { 627 if (UDSL_SKB(skb)->atm.vcc == vcc) { 628 atm_dbg(instance, "%s: popping skb 0x%p\n", __func__, skb); 629 __skb_unlink(skb, &instance->sndqueue); 630 usbatm_pop(vcc, skb); 631 } 632 } 633 spin_unlock_irq(&instance->sndqueue.lock); 634 635 tasklet_disable(&instance->tx_channel.tasklet); 636 if ((skb = instance->current_skb) && (UDSL_SKB(skb)->atm.vcc == vcc)) { 637 atm_dbg(instance, "%s: popping current skb (0x%p)\n", __func__, skb); 638 instance->current_skb = NULL; 639 usbatm_pop(vcc, skb); 640 } 641 tasklet_enable(&instance->tx_channel.tasklet); 642 } 643 644 static int usbatm_atm_send(struct atm_vcc *vcc, struct sk_buff *skb) 645 { 646 struct usbatm_data *instance = vcc->dev->dev_data; 647 struct usbatm_control *ctrl = UDSL_SKB(skb); 648 int err; 649 650 /* racy disconnection check - fine */ 651 if (!instance || instance->disconnected) { 652 #ifdef VERBOSE_DEBUG 653 printk_ratelimited(KERN_DEBUG "%s: %s!\n", __func__, instance ? "disconnected" : "NULL instance"); 654 #endif 655 err = -ENODEV; 656 goto fail; 657 } 658 659 if (vcc->qos.aal != ATM_AAL5) { 660 atm_rldbg(instance, "%s: unsupported ATM type %d!\n", __func__, vcc->qos.aal); 661 err = -EINVAL; 662 goto fail; 663 } 664 665 if (skb->len > ATM_MAX_AAL5_PDU) { 666 atm_rldbg(instance, "%s: packet too long (%d vs %d)!\n", 667 __func__, skb->len, ATM_MAX_AAL5_PDU); 668 err = -EINVAL; 669 goto fail; 670 } 671 672 PACKETDEBUG(instance, skb->data, skb->len); 673 674 /* initialize the control block */ 675 ctrl->atm.vcc = vcc; 676 ctrl->len = skb->len; 677 ctrl->crc = crc32_be(~0, skb->data, skb->len); 678 679 skb_queue_tail(&instance->sndqueue, skb); 680 tasklet_schedule(&instance->tx_channel.tasklet); 681 682 return 0; 683 684 fail: 685 usbatm_pop(vcc, skb); 686 return err; 687 } 688 689 690 /******************** 691 ** bean counting ** 692 ********************/ 693 694 static void usbatm_destroy_instance(struct kref *kref) 695 { 696 struct usbatm_data *instance = container_of(kref, struct usbatm_data, refcount); 697 698 tasklet_kill(&instance->rx_channel.tasklet); 699 tasklet_kill(&instance->tx_channel.tasklet); 700 usb_put_dev(instance->usb_dev); 701 kfree(instance); 702 } 703 704 static void usbatm_get_instance(struct usbatm_data *instance) 705 { 706 kref_get(&instance->refcount); 707 } 708 709 static void usbatm_put_instance(struct usbatm_data *instance) 710 { 711 kref_put(&instance->refcount, usbatm_destroy_instance); 712 } 713 714 715 /********** 716 ** ATM ** 717 **********/ 718 719 static void usbatm_atm_dev_close(struct atm_dev *atm_dev) 720 { 721 struct usbatm_data *instance = atm_dev->dev_data; 722 723 if (!instance) 724 return; 725 726 atm_dev->dev_data = NULL; /* catch bugs */ 727 usbatm_put_instance(instance); /* taken in usbatm_atm_init */ 728 } 729 730 static int usbatm_atm_proc_read(struct atm_dev *atm_dev, loff_t *pos, char *page) 731 { 732 struct usbatm_data *instance = atm_dev->dev_data; 733 int left = *pos; 734 735 if (!instance) 736 return -ENODEV; 737 738 if (!left--) 739 return sprintf(page, "%s\n", instance->description); 740 741 if (!left--) 742 return sprintf(page, "MAC: %pM\n", atm_dev->esi); 743 744 if (!left--) 745 return sprintf(page, 746 "AAL5: tx %d ( %d err ), rx %d ( %d err, %d drop )\n", 747 atomic_read(&atm_dev->stats.aal5.tx), 748 atomic_read(&atm_dev->stats.aal5.tx_err), 749 atomic_read(&atm_dev->stats.aal5.rx), 750 atomic_read(&atm_dev->stats.aal5.rx_err), 751 atomic_read(&atm_dev->stats.aal5.rx_drop)); 752 753 if (!left--) { 754 if (instance->disconnected) 755 return sprintf(page, "Disconnected\n"); 756 else 757 switch (atm_dev->signal) { 758 case ATM_PHY_SIG_FOUND: 759 return sprintf(page, "Line up\n"); 760 case ATM_PHY_SIG_LOST: 761 return sprintf(page, "Line down\n"); 762 default: 763 return sprintf(page, "Line state unknown\n"); 764 } 765 } 766 767 return 0; 768 } 769 770 static int usbatm_atm_open(struct atm_vcc *vcc) 771 { 772 struct usbatm_data *instance = vcc->dev->dev_data; 773 struct usbatm_vcc_data *new = NULL; 774 int ret; 775 int vci = vcc->vci; 776 short vpi = vcc->vpi; 777 778 if (!instance) 779 return -ENODEV; 780 781 /* only support AAL5 */ 782 if ((vcc->qos.aal != ATM_AAL5)) { 783 atm_warn(instance, "%s: unsupported ATM type %d!\n", __func__, vcc->qos.aal); 784 return -EINVAL; 785 } 786 787 /* sanity checks */ 788 if ((vcc->qos.rxtp.max_sdu < 0) || (vcc->qos.rxtp.max_sdu > ATM_MAX_AAL5_PDU)) { 789 atm_dbg(instance, "%s: max_sdu %d out of range!\n", __func__, vcc->qos.rxtp.max_sdu); 790 return -EINVAL; 791 } 792 793 mutex_lock(&instance->serialize); /* vs self, usbatm_atm_close, usbatm_usb_disconnect */ 794 795 if (instance->disconnected) { 796 atm_dbg(instance, "%s: disconnected!\n", __func__); 797 ret = -ENODEV; 798 goto fail; 799 } 800 801 if (usbatm_find_vcc(instance, vpi, vci)) { 802 atm_dbg(instance, "%s: %hd/%d already in use!\n", __func__, vpi, vci); 803 ret = -EADDRINUSE; 804 goto fail; 805 } 806 807 new = kzalloc(sizeof(struct usbatm_vcc_data), GFP_KERNEL); 808 if (!new) { 809 ret = -ENOMEM; 810 goto fail; 811 } 812 813 new->vcc = vcc; 814 new->vpi = vpi; 815 new->vci = vci; 816 817 new->sarb = alloc_skb(usbatm_pdu_length(vcc->qos.rxtp.max_sdu), GFP_KERNEL); 818 if (!new->sarb) { 819 atm_err(instance, "%s: no memory for SAR buffer!\n", __func__); 820 ret = -ENOMEM; 821 goto fail; 822 } 823 824 vcc->dev_data = new; 825 826 tasklet_disable(&instance->rx_channel.tasklet); 827 instance->cached_vcc = new; 828 instance->cached_vpi = vpi; 829 instance->cached_vci = vci; 830 list_add(&new->list, &instance->vcc_list); 831 tasklet_enable(&instance->rx_channel.tasklet); 832 833 set_bit(ATM_VF_ADDR, &vcc->flags); 834 set_bit(ATM_VF_PARTIAL, &vcc->flags); 835 set_bit(ATM_VF_READY, &vcc->flags); 836 837 mutex_unlock(&instance->serialize); 838 839 atm_dbg(instance, "%s: allocated vcc data 0x%p\n", __func__, new); 840 841 return 0; 842 843 fail: 844 kfree(new); 845 mutex_unlock(&instance->serialize); 846 return ret; 847 } 848 849 static void usbatm_atm_close(struct atm_vcc *vcc) 850 { 851 struct usbatm_data *instance = vcc->dev->dev_data; 852 struct usbatm_vcc_data *vcc_data = vcc->dev_data; 853 854 if (!instance || !vcc_data) 855 return; 856 857 usbatm_cancel_send(instance, vcc); 858 859 mutex_lock(&instance->serialize); /* vs self, usbatm_atm_open, usbatm_usb_disconnect */ 860 861 tasklet_disable(&instance->rx_channel.tasklet); 862 if (instance->cached_vcc == vcc_data) { 863 instance->cached_vcc = NULL; 864 instance->cached_vpi = ATM_VPI_UNSPEC; 865 instance->cached_vci = ATM_VCI_UNSPEC; 866 } 867 list_del(&vcc_data->list); 868 tasklet_enable(&instance->rx_channel.tasklet); 869 870 kfree_skb(vcc_data->sarb); 871 vcc_data->sarb = NULL; 872 873 kfree(vcc_data); 874 vcc->dev_data = NULL; 875 876 vcc->vpi = ATM_VPI_UNSPEC; 877 vcc->vci = ATM_VCI_UNSPEC; 878 clear_bit(ATM_VF_READY, &vcc->flags); 879 clear_bit(ATM_VF_PARTIAL, &vcc->flags); 880 clear_bit(ATM_VF_ADDR, &vcc->flags); 881 882 mutex_unlock(&instance->serialize); 883 } 884 885 static int usbatm_atm_ioctl(struct atm_dev *atm_dev, unsigned int cmd, 886 void __user *arg) 887 { 888 struct usbatm_data *instance = atm_dev->dev_data; 889 890 if (!instance || instance->disconnected) 891 return -ENODEV; 892 893 switch (cmd) { 894 case ATM_QUERYLOOP: 895 return put_user(ATM_LM_NONE, (int __user *)arg) ? -EFAULT : 0; 896 default: 897 return -ENOIOCTLCMD; 898 } 899 } 900 901 static int usbatm_atm_init(struct usbatm_data *instance) 902 { 903 struct atm_dev *atm_dev; 904 int ret, i; 905 906 /* ATM init. The ATM initialization scheme suffers from an intrinsic race 907 * condition: callbacks we register can be executed at once, before we have 908 * initialized the struct atm_dev. To protect against this, all callbacks 909 * abort if atm_dev->dev_data is NULL. */ 910 atm_dev = atm_dev_register(instance->driver_name, 911 &instance->usb_intf->dev, &usbatm_atm_devops, 912 -1, NULL); 913 if (!atm_dev) { 914 usb_err(instance, "%s: failed to register ATM device!\n", __func__); 915 return -1; 916 } 917 918 instance->atm_dev = atm_dev; 919 920 atm_dev->ci_range.vpi_bits = ATM_CI_MAX; 921 atm_dev->ci_range.vci_bits = ATM_CI_MAX; 922 atm_dev->signal = ATM_PHY_SIG_UNKNOWN; 923 924 /* temp init ATM device, set to 128kbit */ 925 atm_dev->link_rate = 128 * 1000 / 424; 926 927 if (instance->driver->atm_start && ((ret = instance->driver->atm_start(instance, atm_dev)) < 0)) { 928 atm_err(instance, "%s: atm_start failed: %d!\n", __func__, ret); 929 goto fail; 930 } 931 932 usbatm_get_instance(instance); /* dropped in usbatm_atm_dev_close */ 933 934 /* ready for ATM callbacks */ 935 mb(); 936 atm_dev->dev_data = instance; 937 938 /* submit all rx URBs */ 939 for (i = 0; i < num_rcv_urbs; i++) 940 usbatm_submit_urb(instance->urbs[i]); 941 942 return 0; 943 944 fail: 945 instance->atm_dev = NULL; 946 atm_dev_deregister(atm_dev); /* usbatm_atm_dev_close will eventually be called */ 947 return ret; 948 } 949 950 951 /********** 952 ** USB ** 953 **********/ 954 955 static int usbatm_do_heavy_init(void *arg) 956 { 957 struct usbatm_data *instance = arg; 958 int ret; 959 960 allow_signal(SIGTERM); 961 complete(&instance->thread_started); 962 963 ret = instance->driver->heavy_init(instance, instance->usb_intf); 964 965 if (!ret) 966 ret = usbatm_atm_init(instance); 967 968 mutex_lock(&instance->serialize); 969 instance->thread = NULL; 970 mutex_unlock(&instance->serialize); 971 972 kthread_complete_and_exit(&instance->thread_exited, ret); 973 } 974 975 static int usbatm_heavy_init(struct usbatm_data *instance) 976 { 977 struct task_struct *t; 978 979 t = kthread_create(usbatm_do_heavy_init, instance, "%s", 980 instance->driver->driver_name); 981 if (IS_ERR(t)) { 982 usb_err(instance, "%s: failed to create kernel_thread (%ld)!\n", 983 __func__, PTR_ERR(t)); 984 return PTR_ERR(t); 985 } 986 987 instance->thread = t; 988 wake_up_process(t); 989 wait_for_completion(&instance->thread_started); 990 991 return 0; 992 } 993 994 static void usbatm_tasklet_schedule(struct timer_list *t) 995 { 996 struct usbatm_channel *channel = from_timer(channel, t, delay); 997 998 tasklet_schedule(&channel->tasklet); 999 } 1000 1001 static void usbatm_init_channel(struct usbatm_channel *channel) 1002 { 1003 spin_lock_init(&channel->lock); 1004 INIT_LIST_HEAD(&channel->list); 1005 timer_setup(&channel->delay, usbatm_tasklet_schedule, 0); 1006 } 1007 1008 int usbatm_usb_probe(struct usb_interface *intf, const struct usb_device_id *id, 1009 struct usbatm_driver *driver) 1010 { 1011 struct device *dev = &intf->dev; 1012 struct usb_device *usb_dev = interface_to_usbdev(intf); 1013 struct usbatm_data *instance; 1014 char *buf; 1015 int error = -ENOMEM; 1016 int i, length; 1017 unsigned int maxpacket, num_packets; 1018 size_t size; 1019 1020 /* instance init */ 1021 size = struct_size(instance, urbs, num_rcv_urbs + num_snd_urbs); 1022 instance = kzalloc(size, GFP_KERNEL); 1023 if (!instance) 1024 return -ENOMEM; 1025 1026 /* public fields */ 1027 1028 instance->driver = driver; 1029 strscpy(instance->driver_name, driver->driver_name, 1030 sizeof(instance->driver_name)); 1031 1032 instance->usb_dev = usb_dev; 1033 instance->usb_intf = intf; 1034 1035 buf = instance->description; 1036 length = sizeof(instance->description); 1037 1038 if ((i = usb_string(usb_dev, usb_dev->descriptor.iProduct, buf, length)) < 0) 1039 goto bind; 1040 1041 buf += i; 1042 length -= i; 1043 1044 i = scnprintf(buf, length, " ("); 1045 buf += i; 1046 length -= i; 1047 1048 if (length <= 0 || (i = usb_make_path(usb_dev, buf, length)) < 0) 1049 goto bind; 1050 1051 buf += i; 1052 length -= i; 1053 1054 snprintf(buf, length, ")"); 1055 1056 bind: 1057 if (driver->bind && (error = driver->bind(instance, intf, id)) < 0) { 1058 dev_err(dev, "%s: bind failed: %d!\n", __func__, error); 1059 goto fail_free; 1060 } 1061 1062 /* private fields */ 1063 1064 kref_init(&instance->refcount); /* dropped in usbatm_usb_disconnect */ 1065 mutex_init(&instance->serialize); 1066 1067 instance->thread = NULL; 1068 init_completion(&instance->thread_started); 1069 init_completion(&instance->thread_exited); 1070 1071 INIT_LIST_HEAD(&instance->vcc_list); 1072 skb_queue_head_init(&instance->sndqueue); 1073 1074 usbatm_init_channel(&instance->rx_channel); 1075 usbatm_init_channel(&instance->tx_channel); 1076 tasklet_setup(&instance->rx_channel.tasklet, usbatm_rx_process); 1077 tasklet_setup(&instance->tx_channel.tasklet, usbatm_tx_process); 1078 instance->rx_channel.stride = ATM_CELL_SIZE + driver->rx_padding; 1079 instance->tx_channel.stride = ATM_CELL_SIZE + driver->tx_padding; 1080 instance->rx_channel.usbatm = instance->tx_channel.usbatm = instance; 1081 1082 if ((instance->flags & UDSL_USE_ISOC) && driver->isoc_in) 1083 instance->rx_channel.endpoint = usb_rcvisocpipe(usb_dev, driver->isoc_in); 1084 else 1085 instance->rx_channel.endpoint = usb_rcvbulkpipe(usb_dev, driver->bulk_in); 1086 1087 instance->tx_channel.endpoint = usb_sndbulkpipe(usb_dev, driver->bulk_out); 1088 1089 /* tx buffer size must be a positive multiple of the stride */ 1090 instance->tx_channel.buf_size = max(instance->tx_channel.stride, 1091 snd_buf_bytes - (snd_buf_bytes % instance->tx_channel.stride)); 1092 1093 /* rx buffer size must be a positive multiple of the endpoint maxpacket */ 1094 maxpacket = usb_maxpacket(usb_dev, instance->rx_channel.endpoint); 1095 1096 if ((maxpacket < 1) || (maxpacket > UDSL_MAX_BUF_SIZE)) { 1097 dev_err(dev, "%s: invalid endpoint %02x!\n", __func__, 1098 usb_pipeendpoint(instance->rx_channel.endpoint)); 1099 error = -EINVAL; 1100 goto fail_unbind; 1101 } 1102 1103 num_packets = max(1U, (rcv_buf_bytes + maxpacket / 2) / maxpacket); /* round */ 1104 1105 if (num_packets * maxpacket > UDSL_MAX_BUF_SIZE) 1106 num_packets--; 1107 1108 instance->rx_channel.buf_size = num_packets * maxpacket; 1109 instance->rx_channel.packet_size = maxpacket; 1110 1111 for (i = 0; i < 2; i++) { 1112 struct usbatm_channel *channel = i ? 1113 &instance->tx_channel : &instance->rx_channel; 1114 1115 dev_dbg(dev, "%s: using %d byte buffer for %s channel 0x%p\n", 1116 __func__, channel->buf_size, i ? "tx" : "rx", channel); 1117 } 1118 1119 /* initialize urbs */ 1120 1121 for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) { 1122 u8 *buffer; 1123 struct usbatm_channel *channel = i < num_rcv_urbs ? 1124 &instance->rx_channel : &instance->tx_channel; 1125 struct urb *urb; 1126 unsigned int iso_packets = usb_pipeisoc(channel->endpoint) ? channel->buf_size / channel->packet_size : 0; 1127 1128 urb = usb_alloc_urb(iso_packets, GFP_KERNEL); 1129 if (!urb) { 1130 error = -ENOMEM; 1131 goto fail_unbind; 1132 } 1133 1134 instance->urbs[i] = urb; 1135 1136 /* zero the tx padding to avoid leaking information */ 1137 buffer = kzalloc(channel->buf_size, GFP_KERNEL); 1138 if (!buffer) { 1139 error = -ENOMEM; 1140 goto fail_unbind; 1141 } 1142 1143 usb_fill_bulk_urb(urb, instance->usb_dev, channel->endpoint, 1144 buffer, channel->buf_size, usbatm_complete, channel); 1145 if (iso_packets) { 1146 int j; 1147 urb->interval = 1; 1148 urb->transfer_flags = URB_ISO_ASAP; 1149 urb->number_of_packets = iso_packets; 1150 for (j = 0; j < iso_packets; j++) { 1151 urb->iso_frame_desc[j].offset = channel->packet_size * j; 1152 urb->iso_frame_desc[j].length = channel->packet_size; 1153 } 1154 } 1155 1156 /* put all tx URBs on the list of spares */ 1157 if (i >= num_rcv_urbs) 1158 list_add_tail(&urb->urb_list, &channel->list); 1159 1160 vdbg(&intf->dev, "%s: alloced buffer 0x%p buf size %u urb 0x%p", 1161 __func__, urb->transfer_buffer, urb->transfer_buffer_length, urb); 1162 } 1163 1164 instance->cached_vpi = ATM_VPI_UNSPEC; 1165 instance->cached_vci = ATM_VCI_UNSPEC; 1166 instance->cell_buf = kmalloc(instance->rx_channel.stride, GFP_KERNEL); 1167 1168 if (!instance->cell_buf) { 1169 error = -ENOMEM; 1170 goto fail_unbind; 1171 } 1172 1173 if (!(instance->flags & UDSL_SKIP_HEAVY_INIT) && driver->heavy_init) { 1174 error = usbatm_heavy_init(instance); 1175 } else { 1176 complete(&instance->thread_exited); /* pretend that heavy_init was run */ 1177 error = usbatm_atm_init(instance); 1178 } 1179 1180 if (error < 0) 1181 goto fail_unbind; 1182 1183 usb_get_dev(usb_dev); 1184 usb_set_intfdata(intf, instance); 1185 1186 return 0; 1187 1188 fail_unbind: 1189 if (instance->driver->unbind) 1190 instance->driver->unbind(instance, intf); 1191 fail_free: 1192 kfree(instance->cell_buf); 1193 1194 for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) { 1195 if (instance->urbs[i]) 1196 kfree(instance->urbs[i]->transfer_buffer); 1197 usb_free_urb(instance->urbs[i]); 1198 } 1199 1200 kfree(instance); 1201 1202 return error; 1203 } 1204 EXPORT_SYMBOL_GPL(usbatm_usb_probe); 1205 1206 void usbatm_usb_disconnect(struct usb_interface *intf) 1207 { 1208 struct device *dev = &intf->dev; 1209 struct usbatm_data *instance = usb_get_intfdata(intf); 1210 struct usbatm_vcc_data *vcc_data; 1211 int i; 1212 1213 if (!instance) { 1214 dev_dbg(dev, "%s: NULL instance!\n", __func__); 1215 return; 1216 } 1217 1218 usb_set_intfdata(intf, NULL); 1219 1220 mutex_lock(&instance->serialize); 1221 instance->disconnected = 1; 1222 if (instance->thread != NULL) 1223 send_sig(SIGTERM, instance->thread, 1); 1224 mutex_unlock(&instance->serialize); 1225 1226 wait_for_completion(&instance->thread_exited); 1227 1228 mutex_lock(&instance->serialize); 1229 list_for_each_entry(vcc_data, &instance->vcc_list, list) 1230 vcc_release_async(vcc_data->vcc, -EPIPE); 1231 mutex_unlock(&instance->serialize); 1232 1233 tasklet_disable(&instance->rx_channel.tasklet); 1234 tasklet_disable(&instance->tx_channel.tasklet); 1235 1236 for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) 1237 usb_kill_urb(instance->urbs[i]); 1238 1239 del_timer_sync(&instance->rx_channel.delay); 1240 del_timer_sync(&instance->tx_channel.delay); 1241 1242 /* turn usbatm_[rt]x_process into something close to a no-op */ 1243 /* no need to take the spinlock */ 1244 INIT_LIST_HEAD(&instance->rx_channel.list); 1245 INIT_LIST_HEAD(&instance->tx_channel.list); 1246 1247 tasklet_enable(&instance->rx_channel.tasklet); 1248 tasklet_enable(&instance->tx_channel.tasklet); 1249 1250 if (instance->atm_dev && instance->driver->atm_stop) 1251 instance->driver->atm_stop(instance, instance->atm_dev); 1252 1253 if (instance->driver->unbind) 1254 instance->driver->unbind(instance, intf); 1255 1256 instance->driver_data = NULL; 1257 1258 for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) { 1259 kfree(instance->urbs[i]->transfer_buffer); 1260 usb_free_urb(instance->urbs[i]); 1261 } 1262 1263 kfree(instance->cell_buf); 1264 1265 /* ATM finalize */ 1266 if (instance->atm_dev) { 1267 atm_dev_deregister(instance->atm_dev); 1268 instance->atm_dev = NULL; 1269 } 1270 1271 usbatm_put_instance(instance); /* taken in usbatm_usb_probe */ 1272 } 1273 EXPORT_SYMBOL_GPL(usbatm_usb_disconnect); 1274 1275 1276 /*********** 1277 ** init ** 1278 ***********/ 1279 1280 static int __init usbatm_usb_init(void) 1281 { 1282 if (sizeof(struct usbatm_control) > sizeof_field(struct sk_buff, cb)) { 1283 pr_err("%s unusable with this kernel!\n", usbatm_driver_name); 1284 return -EIO; 1285 } 1286 1287 if ((num_rcv_urbs > UDSL_MAX_RCV_URBS) 1288 || (num_snd_urbs > UDSL_MAX_SND_URBS) 1289 || (rcv_buf_bytes < 1) 1290 || (rcv_buf_bytes > UDSL_MAX_BUF_SIZE) 1291 || (snd_buf_bytes < 1) 1292 || (snd_buf_bytes > UDSL_MAX_BUF_SIZE)) 1293 return -EINVAL; 1294 1295 return 0; 1296 } 1297 module_init(usbatm_usb_init); 1298 1299 static void __exit usbatm_usb_exit(void) 1300 { 1301 } 1302 module_exit(usbatm_usb_exit); 1303 1304 MODULE_AUTHOR(DRIVER_AUTHOR); 1305 MODULE_DESCRIPTION(DRIVER_DESC); 1306 MODULE_LICENSE("GPL"); 1307 1308 /************ 1309 ** debug ** 1310 ************/ 1311 1312 #ifdef VERBOSE_DEBUG 1313 static int usbatm_print_packet(struct usbatm_data *instance, 1314 const unsigned char *data, int len) 1315 { 1316 unsigned char buffer[256]; 1317 int i = 0, j = 0; 1318 1319 for (i = 0; i < len;) { 1320 buffer[0] = '\0'; 1321 sprintf(buffer, "%.3d :", i); 1322 for (j = 0; (j < 16) && (i < len); j++, i++) 1323 sprintf(buffer, "%s %2.2x", buffer, data[i]); 1324 dev_dbg(&instance->usb_intf->dev, "%s", buffer); 1325 } 1326 return i; 1327 } 1328 #endif 1329