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 /* usually in_interrupt(), but not always */ 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(unsigned long data) 515 { 516 struct usbatm_data *instance = (struct usbatm_data *)data; 517 struct urb *urb; 518 519 while ((urb = usbatm_pop_urb(&instance->rx_channel))) { 520 vdbg(&instance->usb_intf->dev, 521 "%s: processing urb 0x%p", __func__, urb); 522 523 if (usb_pipeisoc(urb->pipe)) { 524 unsigned char *merge_start = NULL; 525 unsigned int merge_length = 0; 526 const unsigned int packet_size = instance->rx_channel.packet_size; 527 int i; 528 529 for (i = 0; i < urb->number_of_packets; i++) { 530 if (!urb->iso_frame_desc[i].status) { 531 unsigned int actual_length = urb->iso_frame_desc[i].actual_length; 532 533 if (!merge_length) 534 merge_start = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset; 535 merge_length += actual_length; 536 if (merge_length && (actual_length < packet_size)) { 537 usbatm_extract_cells(instance, merge_start, merge_length); 538 merge_length = 0; 539 } 540 } else { 541 atm_rldbg(instance, "%s: status %d in frame %d!\n", __func__, urb->status, i); 542 if (merge_length) 543 usbatm_extract_cells(instance, merge_start, merge_length); 544 merge_length = 0; 545 instance->buf_usage = 0; 546 } 547 } 548 549 if (merge_length) 550 usbatm_extract_cells(instance, merge_start, merge_length); 551 } else 552 if (!urb->status) 553 usbatm_extract_cells(instance, urb->transfer_buffer, urb->actual_length); 554 else 555 instance->buf_usage = 0; 556 557 if (usbatm_submit_urb(urb)) 558 return; 559 } 560 } 561 562 563 /*********** 564 ** send ** 565 ***********/ 566 567 static void usbatm_tx_process(unsigned long data) 568 { 569 struct usbatm_data *instance = (struct usbatm_data *)data; 570 struct sk_buff *skb = instance->current_skb; 571 struct urb *urb = NULL; 572 const unsigned int buf_size = instance->tx_channel.buf_size; 573 unsigned int bytes_written = 0; 574 u8 *buffer = NULL; 575 576 if (!skb) 577 skb = skb_dequeue(&instance->sndqueue); 578 579 while (skb) { 580 if (!urb) { 581 urb = usbatm_pop_urb(&instance->tx_channel); 582 if (!urb) 583 break; /* no more senders */ 584 buffer = urb->transfer_buffer; 585 bytes_written = (urb->status == -EAGAIN) ? 586 urb->transfer_buffer_length : 0; 587 } 588 589 bytes_written += usbatm_write_cells(instance, skb, 590 buffer + bytes_written, 591 buf_size - bytes_written); 592 593 vdbg(&instance->usb_intf->dev, 594 "%s: wrote %u bytes from skb 0x%p to urb 0x%p", 595 __func__, bytes_written, skb, urb); 596 597 if (!UDSL_SKB(skb)->len) { 598 struct atm_vcc *vcc = UDSL_SKB(skb)->atm.vcc; 599 600 usbatm_pop(vcc, skb); 601 atomic_inc(&vcc->stats->tx); 602 603 skb = skb_dequeue(&instance->sndqueue); 604 } 605 606 if (bytes_written == buf_size || (!skb && bytes_written)) { 607 urb->transfer_buffer_length = bytes_written; 608 609 if (usbatm_submit_urb(urb)) 610 break; 611 urb = NULL; 612 } 613 } 614 615 instance->current_skb = skb; 616 } 617 618 static void usbatm_cancel_send(struct usbatm_data *instance, 619 struct atm_vcc *vcc) 620 { 621 struct sk_buff *skb, *n; 622 623 spin_lock_irq(&instance->sndqueue.lock); 624 skb_queue_walk_safe(&instance->sndqueue, skb, n) { 625 if (UDSL_SKB(skb)->atm.vcc == vcc) { 626 atm_dbg(instance, "%s: popping skb 0x%p\n", __func__, skb); 627 __skb_unlink(skb, &instance->sndqueue); 628 usbatm_pop(vcc, skb); 629 } 630 } 631 spin_unlock_irq(&instance->sndqueue.lock); 632 633 tasklet_disable(&instance->tx_channel.tasklet); 634 if ((skb = instance->current_skb) && (UDSL_SKB(skb)->atm.vcc == vcc)) { 635 atm_dbg(instance, "%s: popping current skb (0x%p)\n", __func__, skb); 636 instance->current_skb = NULL; 637 usbatm_pop(vcc, skb); 638 } 639 tasklet_enable(&instance->tx_channel.tasklet); 640 } 641 642 static int usbatm_atm_send(struct atm_vcc *vcc, struct sk_buff *skb) 643 { 644 struct usbatm_data *instance = vcc->dev->dev_data; 645 struct usbatm_control *ctrl = UDSL_SKB(skb); 646 int err; 647 648 /* racy disconnection check - fine */ 649 if (!instance || instance->disconnected) { 650 #ifdef VERBOSE_DEBUG 651 printk_ratelimited(KERN_DEBUG "%s: %s!\n", __func__, instance ? "disconnected" : "NULL instance"); 652 #endif 653 err = -ENODEV; 654 goto fail; 655 } 656 657 if (vcc->qos.aal != ATM_AAL5) { 658 atm_rldbg(instance, "%s: unsupported ATM type %d!\n", __func__, vcc->qos.aal); 659 err = -EINVAL; 660 goto fail; 661 } 662 663 if (skb->len > ATM_MAX_AAL5_PDU) { 664 atm_rldbg(instance, "%s: packet too long (%d vs %d)!\n", 665 __func__, skb->len, ATM_MAX_AAL5_PDU); 666 err = -EINVAL; 667 goto fail; 668 } 669 670 PACKETDEBUG(instance, skb->data, skb->len); 671 672 /* initialize the control block */ 673 ctrl->atm.vcc = vcc; 674 ctrl->len = skb->len; 675 ctrl->crc = crc32_be(~0, skb->data, skb->len); 676 677 skb_queue_tail(&instance->sndqueue, skb); 678 tasklet_schedule(&instance->tx_channel.tasklet); 679 680 return 0; 681 682 fail: 683 usbatm_pop(vcc, skb); 684 return err; 685 } 686 687 688 /******************** 689 ** bean counting ** 690 ********************/ 691 692 static void usbatm_destroy_instance(struct kref *kref) 693 { 694 struct usbatm_data *instance = container_of(kref, struct usbatm_data, refcount); 695 696 tasklet_kill(&instance->rx_channel.tasklet); 697 tasklet_kill(&instance->tx_channel.tasklet); 698 usb_put_dev(instance->usb_dev); 699 kfree(instance); 700 } 701 702 static void usbatm_get_instance(struct usbatm_data *instance) 703 { 704 kref_get(&instance->refcount); 705 } 706 707 static void usbatm_put_instance(struct usbatm_data *instance) 708 { 709 kref_put(&instance->refcount, usbatm_destroy_instance); 710 } 711 712 713 /********** 714 ** ATM ** 715 **********/ 716 717 static void usbatm_atm_dev_close(struct atm_dev *atm_dev) 718 { 719 struct usbatm_data *instance = atm_dev->dev_data; 720 721 if (!instance) 722 return; 723 724 atm_dev->dev_data = NULL; /* catch bugs */ 725 usbatm_put_instance(instance); /* taken in usbatm_atm_init */ 726 } 727 728 static int usbatm_atm_proc_read(struct atm_dev *atm_dev, loff_t *pos, char *page) 729 { 730 struct usbatm_data *instance = atm_dev->dev_data; 731 int left = *pos; 732 733 if (!instance) 734 return -ENODEV; 735 736 if (!left--) 737 return sprintf(page, "%s\n", instance->description); 738 739 if (!left--) 740 return sprintf(page, "MAC: %pM\n", atm_dev->esi); 741 742 if (!left--) 743 return sprintf(page, 744 "AAL5: tx %d ( %d err ), rx %d ( %d err, %d drop )\n", 745 atomic_read(&atm_dev->stats.aal5.tx), 746 atomic_read(&atm_dev->stats.aal5.tx_err), 747 atomic_read(&atm_dev->stats.aal5.rx), 748 atomic_read(&atm_dev->stats.aal5.rx_err), 749 atomic_read(&atm_dev->stats.aal5.rx_drop)); 750 751 if (!left--) { 752 if (instance->disconnected) 753 return sprintf(page, "Disconnected\n"); 754 else 755 switch (atm_dev->signal) { 756 case ATM_PHY_SIG_FOUND: 757 return sprintf(page, "Line up\n"); 758 case ATM_PHY_SIG_LOST: 759 return sprintf(page, "Line down\n"); 760 default: 761 return sprintf(page, "Line state unknown\n"); 762 } 763 } 764 765 return 0; 766 } 767 768 static int usbatm_atm_open(struct atm_vcc *vcc) 769 { 770 struct usbatm_data *instance = vcc->dev->dev_data; 771 struct usbatm_vcc_data *new = NULL; 772 int ret; 773 int vci = vcc->vci; 774 short vpi = vcc->vpi; 775 776 if (!instance) 777 return -ENODEV; 778 779 /* only support AAL5 */ 780 if ((vcc->qos.aal != ATM_AAL5)) { 781 atm_warn(instance, "%s: unsupported ATM type %d!\n", __func__, vcc->qos.aal); 782 return -EINVAL; 783 } 784 785 /* sanity checks */ 786 if ((vcc->qos.rxtp.max_sdu < 0) || (vcc->qos.rxtp.max_sdu > ATM_MAX_AAL5_PDU)) { 787 atm_dbg(instance, "%s: max_sdu %d out of range!\n", __func__, vcc->qos.rxtp.max_sdu); 788 return -EINVAL; 789 } 790 791 mutex_lock(&instance->serialize); /* vs self, usbatm_atm_close, usbatm_usb_disconnect */ 792 793 if (instance->disconnected) { 794 atm_dbg(instance, "%s: disconnected!\n", __func__); 795 ret = -ENODEV; 796 goto fail; 797 } 798 799 if (usbatm_find_vcc(instance, vpi, vci)) { 800 atm_dbg(instance, "%s: %hd/%d already in use!\n", __func__, vpi, vci); 801 ret = -EADDRINUSE; 802 goto fail; 803 } 804 805 new = kzalloc(sizeof(struct usbatm_vcc_data), GFP_KERNEL); 806 if (!new) { 807 ret = -ENOMEM; 808 goto fail; 809 } 810 811 new->vcc = vcc; 812 new->vpi = vpi; 813 new->vci = vci; 814 815 new->sarb = alloc_skb(usbatm_pdu_length(vcc->qos.rxtp.max_sdu), GFP_KERNEL); 816 if (!new->sarb) { 817 atm_err(instance, "%s: no memory for SAR buffer!\n", __func__); 818 ret = -ENOMEM; 819 goto fail; 820 } 821 822 vcc->dev_data = new; 823 824 tasklet_disable(&instance->rx_channel.tasklet); 825 instance->cached_vcc = new; 826 instance->cached_vpi = vpi; 827 instance->cached_vci = vci; 828 list_add(&new->list, &instance->vcc_list); 829 tasklet_enable(&instance->rx_channel.tasklet); 830 831 set_bit(ATM_VF_ADDR, &vcc->flags); 832 set_bit(ATM_VF_PARTIAL, &vcc->flags); 833 set_bit(ATM_VF_READY, &vcc->flags); 834 835 mutex_unlock(&instance->serialize); 836 837 atm_dbg(instance, "%s: allocated vcc data 0x%p\n", __func__, new); 838 839 return 0; 840 841 fail: 842 kfree(new); 843 mutex_unlock(&instance->serialize); 844 return ret; 845 } 846 847 static void usbatm_atm_close(struct atm_vcc *vcc) 848 { 849 struct usbatm_data *instance = vcc->dev->dev_data; 850 struct usbatm_vcc_data *vcc_data = vcc->dev_data; 851 852 if (!instance || !vcc_data) 853 return; 854 855 usbatm_cancel_send(instance, vcc); 856 857 mutex_lock(&instance->serialize); /* vs self, usbatm_atm_open, usbatm_usb_disconnect */ 858 859 tasklet_disable(&instance->rx_channel.tasklet); 860 if (instance->cached_vcc == vcc_data) { 861 instance->cached_vcc = NULL; 862 instance->cached_vpi = ATM_VPI_UNSPEC; 863 instance->cached_vci = ATM_VCI_UNSPEC; 864 } 865 list_del(&vcc_data->list); 866 tasklet_enable(&instance->rx_channel.tasklet); 867 868 kfree_skb(vcc_data->sarb); 869 vcc_data->sarb = NULL; 870 871 kfree(vcc_data); 872 vcc->dev_data = NULL; 873 874 vcc->vpi = ATM_VPI_UNSPEC; 875 vcc->vci = ATM_VCI_UNSPEC; 876 clear_bit(ATM_VF_READY, &vcc->flags); 877 clear_bit(ATM_VF_PARTIAL, &vcc->flags); 878 clear_bit(ATM_VF_ADDR, &vcc->flags); 879 880 mutex_unlock(&instance->serialize); 881 } 882 883 static int usbatm_atm_ioctl(struct atm_dev *atm_dev, unsigned int cmd, 884 void __user *arg) 885 { 886 struct usbatm_data *instance = atm_dev->dev_data; 887 888 if (!instance || instance->disconnected) 889 return -ENODEV; 890 891 switch (cmd) { 892 case ATM_QUERYLOOP: 893 return put_user(ATM_LM_NONE, (int __user *)arg) ? -EFAULT : 0; 894 default: 895 return -ENOIOCTLCMD; 896 } 897 } 898 899 static int usbatm_atm_init(struct usbatm_data *instance) 900 { 901 struct atm_dev *atm_dev; 902 int ret, i; 903 904 /* ATM init. The ATM initialization scheme suffers from an intrinsic race 905 * condition: callbacks we register can be executed at once, before we have 906 * initialized the struct atm_dev. To protect against this, all callbacks 907 * abort if atm_dev->dev_data is NULL. */ 908 atm_dev = atm_dev_register(instance->driver_name, 909 &instance->usb_intf->dev, &usbatm_atm_devops, 910 -1, NULL); 911 if (!atm_dev) { 912 usb_err(instance, "%s: failed to register ATM device!\n", __func__); 913 return -1; 914 } 915 916 instance->atm_dev = atm_dev; 917 918 atm_dev->ci_range.vpi_bits = ATM_CI_MAX; 919 atm_dev->ci_range.vci_bits = ATM_CI_MAX; 920 atm_dev->signal = ATM_PHY_SIG_UNKNOWN; 921 922 /* temp init ATM device, set to 128kbit */ 923 atm_dev->link_rate = 128 * 1000 / 424; 924 925 if (instance->driver->atm_start && ((ret = instance->driver->atm_start(instance, atm_dev)) < 0)) { 926 atm_err(instance, "%s: atm_start failed: %d!\n", __func__, ret); 927 goto fail; 928 } 929 930 usbatm_get_instance(instance); /* dropped in usbatm_atm_dev_close */ 931 932 /* ready for ATM callbacks */ 933 mb(); 934 atm_dev->dev_data = instance; 935 936 /* submit all rx URBs */ 937 for (i = 0; i < num_rcv_urbs; i++) 938 usbatm_submit_urb(instance->urbs[i]); 939 940 return 0; 941 942 fail: 943 instance->atm_dev = NULL; 944 atm_dev_deregister(atm_dev); /* usbatm_atm_dev_close will eventually be called */ 945 return ret; 946 } 947 948 949 /********** 950 ** USB ** 951 **********/ 952 953 static int usbatm_do_heavy_init(void *arg) 954 { 955 struct usbatm_data *instance = arg; 956 int ret; 957 958 allow_signal(SIGTERM); 959 complete(&instance->thread_started); 960 961 ret = instance->driver->heavy_init(instance, instance->usb_intf); 962 963 if (!ret) 964 ret = usbatm_atm_init(instance); 965 966 mutex_lock(&instance->serialize); 967 instance->thread = NULL; 968 mutex_unlock(&instance->serialize); 969 970 complete_and_exit(&instance->thread_exited, ret); 971 } 972 973 static int usbatm_heavy_init(struct usbatm_data *instance) 974 { 975 struct task_struct *t; 976 977 t = kthread_create(usbatm_do_heavy_init, instance, "%s", 978 instance->driver->driver_name); 979 if (IS_ERR(t)) { 980 usb_err(instance, "%s: failed to create kernel_thread (%ld)!\n", 981 __func__, PTR_ERR(t)); 982 return PTR_ERR(t); 983 } 984 985 instance->thread = t; 986 wake_up_process(t); 987 wait_for_completion(&instance->thread_started); 988 989 return 0; 990 } 991 992 static void usbatm_tasklet_schedule(struct timer_list *t) 993 { 994 struct usbatm_channel *channel = from_timer(channel, t, delay); 995 996 tasklet_schedule(&channel->tasklet); 997 } 998 999 static void usbatm_init_channel(struct usbatm_channel *channel) 1000 { 1001 spin_lock_init(&channel->lock); 1002 INIT_LIST_HEAD(&channel->list); 1003 timer_setup(&channel->delay, usbatm_tasklet_schedule, 0); 1004 } 1005 1006 int usbatm_usb_probe(struct usb_interface *intf, const struct usb_device_id *id, 1007 struct usbatm_driver *driver) 1008 { 1009 struct device *dev = &intf->dev; 1010 struct usb_device *usb_dev = interface_to_usbdev(intf); 1011 struct usbatm_data *instance; 1012 char *buf; 1013 int error = -ENOMEM; 1014 int i, length; 1015 unsigned int maxpacket, num_packets; 1016 1017 /* instance init */ 1018 instance = kzalloc(sizeof(*instance) + sizeof(struct urb *) * (num_rcv_urbs + num_snd_urbs), GFP_KERNEL); 1019 if (!instance) 1020 return -ENOMEM; 1021 1022 /* public fields */ 1023 1024 instance->driver = driver; 1025 strlcpy(instance->driver_name, driver->driver_name, 1026 sizeof(instance->driver_name)); 1027 1028 instance->usb_dev = usb_dev; 1029 instance->usb_intf = intf; 1030 1031 buf = instance->description; 1032 length = sizeof(instance->description); 1033 1034 if ((i = usb_string(usb_dev, usb_dev->descriptor.iProduct, buf, length)) < 0) 1035 goto bind; 1036 1037 buf += i; 1038 length -= i; 1039 1040 i = scnprintf(buf, length, " ("); 1041 buf += i; 1042 length -= i; 1043 1044 if (length <= 0 || (i = usb_make_path(usb_dev, buf, length)) < 0) 1045 goto bind; 1046 1047 buf += i; 1048 length -= i; 1049 1050 snprintf(buf, length, ")"); 1051 1052 bind: 1053 if (driver->bind && (error = driver->bind(instance, intf, id)) < 0) { 1054 dev_err(dev, "%s: bind failed: %d!\n", __func__, error); 1055 goto fail_free; 1056 } 1057 1058 /* private fields */ 1059 1060 kref_init(&instance->refcount); /* dropped in usbatm_usb_disconnect */ 1061 mutex_init(&instance->serialize); 1062 1063 instance->thread = NULL; 1064 init_completion(&instance->thread_started); 1065 init_completion(&instance->thread_exited); 1066 1067 INIT_LIST_HEAD(&instance->vcc_list); 1068 skb_queue_head_init(&instance->sndqueue); 1069 1070 usbatm_init_channel(&instance->rx_channel); 1071 usbatm_init_channel(&instance->tx_channel); 1072 tasklet_init(&instance->rx_channel.tasklet, usbatm_rx_process, (unsigned long)instance); 1073 tasklet_init(&instance->tx_channel.tasklet, usbatm_tx_process, (unsigned long)instance); 1074 instance->rx_channel.stride = ATM_CELL_SIZE + driver->rx_padding; 1075 instance->tx_channel.stride = ATM_CELL_SIZE + driver->tx_padding; 1076 instance->rx_channel.usbatm = instance->tx_channel.usbatm = instance; 1077 1078 if ((instance->flags & UDSL_USE_ISOC) && driver->isoc_in) 1079 instance->rx_channel.endpoint = usb_rcvisocpipe(usb_dev, driver->isoc_in); 1080 else 1081 instance->rx_channel.endpoint = usb_rcvbulkpipe(usb_dev, driver->bulk_in); 1082 1083 instance->tx_channel.endpoint = usb_sndbulkpipe(usb_dev, driver->bulk_out); 1084 1085 /* tx buffer size must be a positive multiple of the stride */ 1086 instance->tx_channel.buf_size = max(instance->tx_channel.stride, 1087 snd_buf_bytes - (snd_buf_bytes % instance->tx_channel.stride)); 1088 1089 /* rx buffer size must be a positive multiple of the endpoint maxpacket */ 1090 maxpacket = usb_maxpacket(usb_dev, instance->rx_channel.endpoint, 0); 1091 1092 if ((maxpacket < 1) || (maxpacket > UDSL_MAX_BUF_SIZE)) { 1093 dev_err(dev, "%s: invalid endpoint %02x!\n", __func__, 1094 usb_pipeendpoint(instance->rx_channel.endpoint)); 1095 error = -EINVAL; 1096 goto fail_unbind; 1097 } 1098 1099 num_packets = max(1U, (rcv_buf_bytes + maxpacket / 2) / maxpacket); /* round */ 1100 1101 if (num_packets * maxpacket > UDSL_MAX_BUF_SIZE) 1102 num_packets--; 1103 1104 instance->rx_channel.buf_size = num_packets * maxpacket; 1105 instance->rx_channel.packet_size = maxpacket; 1106 1107 for (i = 0; i < 2; i++) { 1108 struct usbatm_channel *channel = i ? 1109 &instance->tx_channel : &instance->rx_channel; 1110 1111 dev_dbg(dev, "%s: using %d byte buffer for %s channel 0x%p\n", 1112 __func__, channel->buf_size, i ? "tx" : "rx", channel); 1113 } 1114 1115 /* initialize urbs */ 1116 1117 for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) { 1118 u8 *buffer; 1119 struct usbatm_channel *channel = i < num_rcv_urbs ? 1120 &instance->rx_channel : &instance->tx_channel; 1121 struct urb *urb; 1122 unsigned int iso_packets = usb_pipeisoc(channel->endpoint) ? channel->buf_size / channel->packet_size : 0; 1123 1124 urb = usb_alloc_urb(iso_packets, GFP_KERNEL); 1125 if (!urb) { 1126 error = -ENOMEM; 1127 goto fail_unbind; 1128 } 1129 1130 instance->urbs[i] = urb; 1131 1132 /* zero the tx padding to avoid leaking information */ 1133 buffer = kzalloc(channel->buf_size, GFP_KERNEL); 1134 if (!buffer) { 1135 error = -ENOMEM; 1136 goto fail_unbind; 1137 } 1138 1139 usb_fill_bulk_urb(urb, instance->usb_dev, channel->endpoint, 1140 buffer, channel->buf_size, usbatm_complete, channel); 1141 if (iso_packets) { 1142 int j; 1143 urb->interval = 1; 1144 urb->transfer_flags = URB_ISO_ASAP; 1145 urb->number_of_packets = iso_packets; 1146 for (j = 0; j < iso_packets; j++) { 1147 urb->iso_frame_desc[j].offset = channel->packet_size * j; 1148 urb->iso_frame_desc[j].length = channel->packet_size; 1149 } 1150 } 1151 1152 /* put all tx URBs on the list of spares */ 1153 if (i >= num_rcv_urbs) 1154 list_add_tail(&urb->urb_list, &channel->list); 1155 1156 vdbg(&intf->dev, "%s: alloced buffer 0x%p buf size %u urb 0x%p", 1157 __func__, urb->transfer_buffer, urb->transfer_buffer_length, urb); 1158 } 1159 1160 instance->cached_vpi = ATM_VPI_UNSPEC; 1161 instance->cached_vci = ATM_VCI_UNSPEC; 1162 instance->cell_buf = kmalloc(instance->rx_channel.stride, GFP_KERNEL); 1163 1164 if (!instance->cell_buf) { 1165 error = -ENOMEM; 1166 goto fail_unbind; 1167 } 1168 1169 if (!(instance->flags & UDSL_SKIP_HEAVY_INIT) && driver->heavy_init) { 1170 error = usbatm_heavy_init(instance); 1171 } else { 1172 complete(&instance->thread_exited); /* pretend that heavy_init was run */ 1173 error = usbatm_atm_init(instance); 1174 } 1175 1176 if (error < 0) 1177 goto fail_unbind; 1178 1179 usb_get_dev(usb_dev); 1180 usb_set_intfdata(intf, instance); 1181 1182 return 0; 1183 1184 fail_unbind: 1185 if (instance->driver->unbind) 1186 instance->driver->unbind(instance, intf); 1187 fail_free: 1188 kfree(instance->cell_buf); 1189 1190 for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) { 1191 if (instance->urbs[i]) 1192 kfree(instance->urbs[i]->transfer_buffer); 1193 usb_free_urb(instance->urbs[i]); 1194 } 1195 1196 kfree(instance); 1197 1198 return error; 1199 } 1200 EXPORT_SYMBOL_GPL(usbatm_usb_probe); 1201 1202 void usbatm_usb_disconnect(struct usb_interface *intf) 1203 { 1204 struct device *dev = &intf->dev; 1205 struct usbatm_data *instance = usb_get_intfdata(intf); 1206 struct usbatm_vcc_data *vcc_data; 1207 int i; 1208 1209 if (!instance) { 1210 dev_dbg(dev, "%s: NULL instance!\n", __func__); 1211 return; 1212 } 1213 1214 usb_set_intfdata(intf, NULL); 1215 1216 mutex_lock(&instance->serialize); 1217 instance->disconnected = 1; 1218 if (instance->thread != NULL) 1219 send_sig(SIGTERM, instance->thread, 1); 1220 mutex_unlock(&instance->serialize); 1221 1222 wait_for_completion(&instance->thread_exited); 1223 1224 mutex_lock(&instance->serialize); 1225 list_for_each_entry(vcc_data, &instance->vcc_list, list) 1226 vcc_release_async(vcc_data->vcc, -EPIPE); 1227 mutex_unlock(&instance->serialize); 1228 1229 tasklet_disable(&instance->rx_channel.tasklet); 1230 tasklet_disable(&instance->tx_channel.tasklet); 1231 1232 for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) 1233 usb_kill_urb(instance->urbs[i]); 1234 1235 del_timer_sync(&instance->rx_channel.delay); 1236 del_timer_sync(&instance->tx_channel.delay); 1237 1238 /* turn usbatm_[rt]x_process into something close to a no-op */ 1239 /* no need to take the spinlock */ 1240 INIT_LIST_HEAD(&instance->rx_channel.list); 1241 INIT_LIST_HEAD(&instance->tx_channel.list); 1242 1243 tasklet_enable(&instance->rx_channel.tasklet); 1244 tasklet_enable(&instance->tx_channel.tasklet); 1245 1246 if (instance->atm_dev && instance->driver->atm_stop) 1247 instance->driver->atm_stop(instance, instance->atm_dev); 1248 1249 if (instance->driver->unbind) 1250 instance->driver->unbind(instance, intf); 1251 1252 instance->driver_data = NULL; 1253 1254 for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) { 1255 kfree(instance->urbs[i]->transfer_buffer); 1256 usb_free_urb(instance->urbs[i]); 1257 } 1258 1259 kfree(instance->cell_buf); 1260 1261 /* ATM finalize */ 1262 if (instance->atm_dev) { 1263 atm_dev_deregister(instance->atm_dev); 1264 instance->atm_dev = NULL; 1265 } 1266 1267 usbatm_put_instance(instance); /* taken in usbatm_usb_probe */ 1268 } 1269 EXPORT_SYMBOL_GPL(usbatm_usb_disconnect); 1270 1271 1272 /*********** 1273 ** init ** 1274 ***********/ 1275 1276 static int __init usbatm_usb_init(void) 1277 { 1278 if (sizeof(struct usbatm_control) > sizeof_field(struct sk_buff, cb)) { 1279 printk(KERN_ERR "%s unusable with this kernel!\n", usbatm_driver_name); 1280 return -EIO; 1281 } 1282 1283 if ((num_rcv_urbs > UDSL_MAX_RCV_URBS) 1284 || (num_snd_urbs > UDSL_MAX_SND_URBS) 1285 || (rcv_buf_bytes < 1) 1286 || (rcv_buf_bytes > UDSL_MAX_BUF_SIZE) 1287 || (snd_buf_bytes < 1) 1288 || (snd_buf_bytes > UDSL_MAX_BUF_SIZE)) 1289 return -EINVAL; 1290 1291 return 0; 1292 } 1293 module_init(usbatm_usb_init); 1294 1295 static void __exit usbatm_usb_exit(void) 1296 { 1297 } 1298 module_exit(usbatm_usb_exit); 1299 1300 MODULE_AUTHOR(DRIVER_AUTHOR); 1301 MODULE_DESCRIPTION(DRIVER_DESC); 1302 MODULE_LICENSE("GPL"); 1303 1304 /************ 1305 ** debug ** 1306 ************/ 1307 1308 #ifdef VERBOSE_DEBUG 1309 static int usbatm_print_packet(struct usbatm_data *instance, 1310 const unsigned char *data, int len) 1311 { 1312 unsigned char buffer[256]; 1313 int i = 0, j = 0; 1314 1315 for (i = 0; i < len;) { 1316 buffer[0] = '\0'; 1317 sprintf(buffer, "%.3d :", i); 1318 for (j = 0; (j < 16) && (i < len); j++, i++) 1319 sprintf(buffer, "%s %2.2x", buffer, data[i]); 1320 dev_dbg(&instance->usb_intf->dev, "%s", buffer); 1321 } 1322 return i; 1323 } 1324 #endif 1325