1 /* 2 * CAN driver for PEAK System PCAN-USB adapter 3 * Derived from the PCAN project file driver/src/pcan_usb.c 4 * 5 * Copyright (C) 2003-2010 PEAK System-Technik GmbH 6 * Copyright (C) 2011-2012 Stephane Grosjean <s.grosjean@peak-system.com> 7 * 8 * Many thanks to Klaus Hitschler <klaus.hitschler@gmx.de> 9 * 10 * This program is free software; you can redistribute it and/or modify it 11 * under the terms of the GNU General Public License as published 12 * by the Free Software Foundation; version 2 of the License. 13 * 14 * This program is distributed in the hope that it will be useful, but 15 * WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 */ 19 #include <linux/netdevice.h> 20 #include <linux/usb.h> 21 #include <linux/module.h> 22 23 #include <linux/can.h> 24 #include <linux/can/dev.h> 25 #include <linux/can/error.h> 26 27 #include "pcan_usb_core.h" 28 29 MODULE_SUPPORTED_DEVICE("PEAK-System PCAN-USB adapter"); 30 31 /* PCAN-USB Endpoints */ 32 #define PCAN_USB_EP_CMDOUT 1 33 #define PCAN_USB_EP_CMDIN (PCAN_USB_EP_CMDOUT | USB_DIR_IN) 34 #define PCAN_USB_EP_MSGOUT 2 35 #define PCAN_USB_EP_MSGIN (PCAN_USB_EP_MSGOUT | USB_DIR_IN) 36 37 /* PCAN-USB command struct */ 38 #define PCAN_USB_CMD_FUNC 0 39 #define PCAN_USB_CMD_NUM 1 40 #define PCAN_USB_CMD_ARGS 2 41 #define PCAN_USB_CMD_ARGS_LEN 14 42 #define PCAN_USB_CMD_LEN (PCAN_USB_CMD_ARGS + \ 43 PCAN_USB_CMD_ARGS_LEN) 44 45 /* PCAN-USB command timeout (ms.) */ 46 #define PCAN_USB_COMMAND_TIMEOUT 1000 47 48 /* PCAN-USB startup timeout (ms.) */ 49 #define PCAN_USB_STARTUP_TIMEOUT 10 50 51 /* PCAN-USB rx/tx buffers size */ 52 #define PCAN_USB_RX_BUFFER_SIZE 64 53 #define PCAN_USB_TX_BUFFER_SIZE 64 54 55 #define PCAN_USB_MSG_HEADER_LEN 2 56 57 /* PCAN-USB adapter internal clock (MHz) */ 58 #define PCAN_USB_CRYSTAL_HZ 16000000 59 60 /* PCAN-USB USB message record status/len field */ 61 #define PCAN_USB_STATUSLEN_TIMESTAMP (1 << 7) 62 #define PCAN_USB_STATUSLEN_INTERNAL (1 << 6) 63 #define PCAN_USB_STATUSLEN_EXT_ID (1 << 5) 64 #define PCAN_USB_STATUSLEN_RTR (1 << 4) 65 #define PCAN_USB_STATUSLEN_DLC (0xf) 66 67 /* PCAN-USB error flags */ 68 #define PCAN_USB_ERROR_TXFULL 0x01 69 #define PCAN_USB_ERROR_RXQOVR 0x02 70 #define PCAN_USB_ERROR_BUS_LIGHT 0x04 71 #define PCAN_USB_ERROR_BUS_HEAVY 0x08 72 #define PCAN_USB_ERROR_BUS_OFF 0x10 73 #define PCAN_USB_ERROR_RXQEMPTY 0x20 74 #define PCAN_USB_ERROR_QOVR 0x40 75 #define PCAN_USB_ERROR_TXQFULL 0x80 76 77 /* SJA1000 modes */ 78 #define SJA1000_MODE_NORMAL 0x00 79 #define SJA1000_MODE_INIT 0x01 80 81 /* 82 * tick duration = 42.666 us => 83 * (tick_number * 44739243) >> 20 ~ (tick_number * 42666) / 1000 84 * accuracy = 10^-7 85 */ 86 #define PCAN_USB_TS_DIV_SHIFTER 20 87 #define PCAN_USB_TS_US_PER_TICK 44739243 88 89 /* PCAN-USB messages record types */ 90 #define PCAN_USB_REC_ERROR 1 91 #define PCAN_USB_REC_ANALOG 2 92 #define PCAN_USB_REC_BUSLOAD 3 93 #define PCAN_USB_REC_TS 4 94 #define PCAN_USB_REC_BUSEVT 5 95 96 /* private to PCAN-USB adapter */ 97 struct pcan_usb { 98 struct peak_usb_device dev; 99 struct peak_time_ref time_ref; 100 struct timer_list restart_timer; 101 }; 102 103 /* incoming message context for decoding */ 104 struct pcan_usb_msg_context { 105 u16 ts16; 106 u8 prev_ts8; 107 u8 *ptr; 108 u8 *end; 109 u8 rec_cnt; 110 u8 rec_idx; 111 u8 rec_data_idx; 112 struct net_device *netdev; 113 struct pcan_usb *pdev; 114 }; 115 116 /* 117 * send a command 118 */ 119 static int pcan_usb_send_cmd(struct peak_usb_device *dev, u8 f, u8 n, u8 *p) 120 { 121 int err; 122 int actual_length; 123 124 /* usb device unregistered? */ 125 if (!(dev->state & PCAN_USB_STATE_CONNECTED)) 126 return 0; 127 128 dev->cmd_buf[PCAN_USB_CMD_FUNC] = f; 129 dev->cmd_buf[PCAN_USB_CMD_NUM] = n; 130 131 if (p) 132 memcpy(dev->cmd_buf + PCAN_USB_CMD_ARGS, 133 p, PCAN_USB_CMD_ARGS_LEN); 134 135 err = usb_bulk_msg(dev->udev, 136 usb_sndbulkpipe(dev->udev, PCAN_USB_EP_CMDOUT), 137 dev->cmd_buf, PCAN_USB_CMD_LEN, &actual_length, 138 PCAN_USB_COMMAND_TIMEOUT); 139 if (err) 140 netdev_err(dev->netdev, 141 "sending cmd f=0x%x n=0x%x failure: %d\n", 142 f, n, err); 143 return err; 144 } 145 146 /* 147 * send a command then wait for its response 148 */ 149 static int pcan_usb_wait_rsp(struct peak_usb_device *dev, u8 f, u8 n, u8 *p) 150 { 151 int err; 152 int actual_length; 153 154 /* usb device unregistered? */ 155 if (!(dev->state & PCAN_USB_STATE_CONNECTED)) 156 return 0; 157 158 /* first, send command */ 159 err = pcan_usb_send_cmd(dev, f, n, NULL); 160 if (err) 161 return err; 162 163 err = usb_bulk_msg(dev->udev, 164 usb_rcvbulkpipe(dev->udev, PCAN_USB_EP_CMDIN), 165 dev->cmd_buf, PCAN_USB_CMD_LEN, &actual_length, 166 PCAN_USB_COMMAND_TIMEOUT); 167 if (err) 168 netdev_err(dev->netdev, 169 "waiting rsp f=0x%x n=0x%x failure: %d\n", f, n, err); 170 else if (p) 171 memcpy(p, dev->cmd_buf + PCAN_USB_CMD_ARGS, 172 PCAN_USB_CMD_ARGS_LEN); 173 174 return err; 175 } 176 177 static int pcan_usb_set_sja1000(struct peak_usb_device *dev, u8 mode) 178 { 179 u8 args[PCAN_USB_CMD_ARGS_LEN] = { 180 [1] = mode, 181 }; 182 183 return pcan_usb_send_cmd(dev, 9, 2, args); 184 } 185 186 static int pcan_usb_set_bus(struct peak_usb_device *dev, u8 onoff) 187 { 188 u8 args[PCAN_USB_CMD_ARGS_LEN] = { 189 [0] = !!onoff, 190 }; 191 192 return pcan_usb_send_cmd(dev, 3, 2, args); 193 } 194 195 static int pcan_usb_set_silent(struct peak_usb_device *dev, u8 onoff) 196 { 197 u8 args[PCAN_USB_CMD_ARGS_LEN] = { 198 [0] = !!onoff, 199 }; 200 201 return pcan_usb_send_cmd(dev, 3, 3, args); 202 } 203 204 static int pcan_usb_set_ext_vcc(struct peak_usb_device *dev, u8 onoff) 205 { 206 u8 args[PCAN_USB_CMD_ARGS_LEN] = { 207 [0] = !!onoff, 208 }; 209 210 return pcan_usb_send_cmd(dev, 10, 2, args); 211 } 212 213 /* 214 * set bittiming value to can 215 */ 216 static int pcan_usb_set_bittiming(struct peak_usb_device *dev, 217 struct can_bittiming *bt) 218 { 219 u8 args[PCAN_USB_CMD_ARGS_LEN]; 220 u8 btr0, btr1; 221 222 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6); 223 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) | 224 (((bt->phase_seg2 - 1) & 0x7) << 4); 225 if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) 226 btr1 |= 0x80; 227 228 netdev_info(dev->netdev, "setting BTR0=0x%02x BTR1=0x%02x\n", 229 btr0, btr1); 230 231 args[0] = btr1; 232 args[1] = btr0; 233 234 return pcan_usb_send_cmd(dev, 1, 2, args); 235 } 236 237 /* 238 * init/reset can 239 */ 240 static int pcan_usb_write_mode(struct peak_usb_device *dev, u8 onoff) 241 { 242 int err; 243 244 err = pcan_usb_set_bus(dev, onoff); 245 if (err) 246 return err; 247 248 if (!onoff) { 249 err = pcan_usb_set_sja1000(dev, SJA1000_MODE_INIT); 250 } else { 251 /* the PCAN-USB needs time to init */ 252 set_current_state(TASK_INTERRUPTIBLE); 253 schedule_timeout(msecs_to_jiffies(PCAN_USB_STARTUP_TIMEOUT)); 254 } 255 256 return err; 257 } 258 259 /* 260 * handle end of waiting for the device to reset 261 */ 262 static void pcan_usb_restart(unsigned long arg) 263 { 264 /* notify candev and netdev */ 265 peak_usb_restart_complete((struct peak_usb_device *)arg); 266 } 267 268 /* 269 * handle the submission of the restart urb 270 */ 271 static void pcan_usb_restart_pending(struct urb *urb) 272 { 273 struct pcan_usb *pdev = urb->context; 274 275 /* the PCAN-USB needs time to restart */ 276 mod_timer(&pdev->restart_timer, 277 jiffies + msecs_to_jiffies(PCAN_USB_STARTUP_TIMEOUT)); 278 279 /* can delete usb resources */ 280 peak_usb_async_complete(urb); 281 } 282 283 /* 284 * handle asynchronous restart 285 */ 286 static int pcan_usb_restart_async(struct peak_usb_device *dev, struct urb *urb, 287 u8 *buf) 288 { 289 struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev); 290 291 if (timer_pending(&pdev->restart_timer)) 292 return -EBUSY; 293 294 /* set bus on */ 295 buf[PCAN_USB_CMD_FUNC] = 3; 296 buf[PCAN_USB_CMD_NUM] = 2; 297 buf[PCAN_USB_CMD_ARGS] = 1; 298 299 usb_fill_bulk_urb(urb, dev->udev, 300 usb_sndbulkpipe(dev->udev, PCAN_USB_EP_CMDOUT), 301 buf, PCAN_USB_CMD_LEN, 302 pcan_usb_restart_pending, pdev); 303 304 return usb_submit_urb(urb, GFP_ATOMIC); 305 } 306 307 /* 308 * read serial number from device 309 */ 310 static int pcan_usb_get_serial(struct peak_usb_device *dev, u32 *serial_number) 311 { 312 u8 args[PCAN_USB_CMD_ARGS_LEN]; 313 int err; 314 315 err = pcan_usb_wait_rsp(dev, 6, 1, args); 316 if (err) { 317 netdev_err(dev->netdev, "getting serial failure: %d\n", err); 318 } else if (serial_number) { 319 u32 tmp32; 320 321 memcpy(&tmp32, args, 4); 322 *serial_number = le32_to_cpu(tmp32); 323 } 324 325 return err; 326 } 327 328 /* 329 * read device id from device 330 */ 331 static int pcan_usb_get_device_id(struct peak_usb_device *dev, u32 *device_id) 332 { 333 u8 args[PCAN_USB_CMD_ARGS_LEN]; 334 int err; 335 336 err = pcan_usb_wait_rsp(dev, 4, 1, args); 337 if (err) 338 netdev_err(dev->netdev, "getting device id failure: %d\n", err); 339 else if (device_id) 340 *device_id = args[0]; 341 342 return err; 343 } 344 345 /* 346 * update current time ref with received timestamp 347 */ 348 static int pcan_usb_update_ts(struct pcan_usb_msg_context *mc) 349 { 350 u16 tmp16; 351 352 if ((mc->ptr+2) > mc->end) 353 return -EINVAL; 354 355 memcpy(&tmp16, mc->ptr, 2); 356 357 mc->ts16 = le16_to_cpu(tmp16); 358 359 if (mc->rec_idx > 0) 360 peak_usb_update_ts_now(&mc->pdev->time_ref, mc->ts16); 361 else 362 peak_usb_set_ts_now(&mc->pdev->time_ref, mc->ts16); 363 364 return 0; 365 } 366 367 /* 368 * decode received timestamp 369 */ 370 static int pcan_usb_decode_ts(struct pcan_usb_msg_context *mc, u8 first_packet) 371 { 372 /* only 1st packet supplies a word timestamp */ 373 if (first_packet) { 374 u16 tmp16; 375 376 if ((mc->ptr + 2) > mc->end) 377 return -EINVAL; 378 379 memcpy(&tmp16, mc->ptr, 2); 380 mc->ptr += 2; 381 382 mc->ts16 = le16_to_cpu(tmp16); 383 mc->prev_ts8 = mc->ts16 & 0x00ff; 384 } else { 385 u8 ts8; 386 387 if ((mc->ptr + 1) > mc->end) 388 return -EINVAL; 389 390 ts8 = *mc->ptr++; 391 392 if (ts8 < mc->prev_ts8) 393 mc->ts16 += 0x100; 394 395 mc->ts16 &= 0xff00; 396 mc->ts16 |= ts8; 397 mc->prev_ts8 = ts8; 398 } 399 400 return 0; 401 } 402 403 static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n, 404 u8 status_len) 405 { 406 struct sk_buff *skb; 407 struct can_frame *cf; 408 struct timeval tv; 409 enum can_state new_state; 410 411 /* ignore this error until 1st ts received */ 412 if (n == PCAN_USB_ERROR_QOVR) 413 if (!mc->pdev->time_ref.tick_count) 414 return 0; 415 416 new_state = mc->pdev->dev.can.state; 417 418 switch (mc->pdev->dev.can.state) { 419 case CAN_STATE_ERROR_ACTIVE: 420 if (n & PCAN_USB_ERROR_BUS_LIGHT) { 421 new_state = CAN_STATE_ERROR_WARNING; 422 break; 423 } 424 425 case CAN_STATE_ERROR_WARNING: 426 if (n & PCAN_USB_ERROR_BUS_HEAVY) { 427 new_state = CAN_STATE_ERROR_PASSIVE; 428 break; 429 } 430 if (n & PCAN_USB_ERROR_BUS_OFF) { 431 new_state = CAN_STATE_BUS_OFF; 432 break; 433 } 434 if (n & (PCAN_USB_ERROR_RXQOVR | PCAN_USB_ERROR_QOVR)) { 435 /* 436 * trick to bypass next comparison and process other 437 * errors 438 */ 439 new_state = CAN_STATE_MAX; 440 break; 441 } 442 if ((n & PCAN_USB_ERROR_BUS_LIGHT) == 0) { 443 /* no error (back to active state) */ 444 mc->pdev->dev.can.state = CAN_STATE_ERROR_ACTIVE; 445 return 0; 446 } 447 break; 448 449 case CAN_STATE_ERROR_PASSIVE: 450 if (n & PCAN_USB_ERROR_BUS_OFF) { 451 new_state = CAN_STATE_BUS_OFF; 452 break; 453 } 454 if (n & PCAN_USB_ERROR_BUS_LIGHT) { 455 new_state = CAN_STATE_ERROR_WARNING; 456 break; 457 } 458 if (n & (PCAN_USB_ERROR_RXQOVR | PCAN_USB_ERROR_QOVR)) { 459 /* 460 * trick to bypass next comparison and process other 461 * errors 462 */ 463 new_state = CAN_STATE_MAX; 464 break; 465 } 466 467 if ((n & PCAN_USB_ERROR_BUS_HEAVY) == 0) { 468 /* no error (back to active state) */ 469 mc->pdev->dev.can.state = CAN_STATE_ERROR_ACTIVE; 470 return 0; 471 } 472 break; 473 474 default: 475 /* do nothing waiting for restart */ 476 return 0; 477 } 478 479 /* donot post any error if current state didn't change */ 480 if (mc->pdev->dev.can.state == new_state) 481 return 0; 482 483 /* allocate an skb to store the error frame */ 484 skb = alloc_can_err_skb(mc->netdev, &cf); 485 if (!skb) 486 return -ENOMEM; 487 488 switch (new_state) { 489 case CAN_STATE_BUS_OFF: 490 cf->can_id |= CAN_ERR_BUSOFF; 491 can_bus_off(mc->netdev); 492 break; 493 494 case CAN_STATE_ERROR_PASSIVE: 495 cf->can_id |= CAN_ERR_CRTL; 496 cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE | 497 CAN_ERR_CRTL_RX_PASSIVE; 498 mc->pdev->dev.can.can_stats.error_passive++; 499 break; 500 501 case CAN_STATE_ERROR_WARNING: 502 cf->can_id |= CAN_ERR_CRTL; 503 cf->data[1] |= CAN_ERR_CRTL_TX_WARNING | 504 CAN_ERR_CRTL_RX_WARNING; 505 mc->pdev->dev.can.can_stats.error_warning++; 506 break; 507 508 default: 509 /* CAN_STATE_MAX (trick to handle other errors) */ 510 cf->can_id |= CAN_ERR_CRTL; 511 cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW; 512 mc->netdev->stats.rx_over_errors++; 513 mc->netdev->stats.rx_errors++; 514 515 new_state = mc->pdev->dev.can.state; 516 break; 517 } 518 519 mc->pdev->dev.can.state = new_state; 520 521 if (status_len & PCAN_USB_STATUSLEN_TIMESTAMP) { 522 peak_usb_get_ts_tv(&mc->pdev->time_ref, mc->ts16, &tv); 523 skb->tstamp = timeval_to_ktime(tv); 524 } 525 526 netif_rx(skb); 527 mc->netdev->stats.rx_packets++; 528 mc->netdev->stats.rx_bytes += cf->can_dlc; 529 530 return 0; 531 } 532 533 /* 534 * decode non-data usb message 535 */ 536 static int pcan_usb_decode_status(struct pcan_usb_msg_context *mc, 537 u8 status_len) 538 { 539 u8 rec_len = status_len & PCAN_USB_STATUSLEN_DLC; 540 u8 f, n; 541 int err; 542 543 /* check whether function and number can be read */ 544 if ((mc->ptr + 2) > mc->end) 545 return -EINVAL; 546 547 f = mc->ptr[PCAN_USB_CMD_FUNC]; 548 n = mc->ptr[PCAN_USB_CMD_NUM]; 549 mc->ptr += PCAN_USB_CMD_ARGS; 550 551 if (status_len & PCAN_USB_STATUSLEN_TIMESTAMP) { 552 int err = pcan_usb_decode_ts(mc, !mc->rec_idx); 553 554 if (err) 555 return err; 556 } 557 558 switch (f) { 559 case PCAN_USB_REC_ERROR: 560 err = pcan_usb_decode_error(mc, n, status_len); 561 if (err) 562 return err; 563 break; 564 565 case PCAN_USB_REC_ANALOG: 566 /* analog values (ignored) */ 567 rec_len = 2; 568 break; 569 570 case PCAN_USB_REC_BUSLOAD: 571 /* bus load (ignored) */ 572 rec_len = 1; 573 break; 574 575 case PCAN_USB_REC_TS: 576 /* only timestamp */ 577 if (pcan_usb_update_ts(mc)) 578 return -EINVAL; 579 break; 580 581 case PCAN_USB_REC_BUSEVT: 582 /* error frame/bus event */ 583 if (n & PCAN_USB_ERROR_TXQFULL) 584 netdev_dbg(mc->netdev, "device Tx queue full)\n"); 585 break; 586 default: 587 netdev_err(mc->netdev, "unexpected function %u\n", f); 588 break; 589 } 590 591 if ((mc->ptr + rec_len) > mc->end) 592 return -EINVAL; 593 594 mc->ptr += rec_len; 595 596 return 0; 597 } 598 599 /* 600 * decode data usb message 601 */ 602 static int pcan_usb_decode_data(struct pcan_usb_msg_context *mc, u8 status_len) 603 { 604 u8 rec_len = status_len & PCAN_USB_STATUSLEN_DLC; 605 struct sk_buff *skb; 606 struct can_frame *cf; 607 struct timeval tv; 608 609 skb = alloc_can_skb(mc->netdev, &cf); 610 if (!skb) 611 return -ENOMEM; 612 613 if (status_len & PCAN_USB_STATUSLEN_EXT_ID) { 614 u32 tmp32; 615 616 if ((mc->ptr + 4) > mc->end) 617 goto decode_failed; 618 619 memcpy(&tmp32, mc->ptr, 4); 620 mc->ptr += 4; 621 622 cf->can_id = le32_to_cpu(tmp32 >> 3) | CAN_EFF_FLAG; 623 } else { 624 u16 tmp16; 625 626 if ((mc->ptr + 2) > mc->end) 627 goto decode_failed; 628 629 memcpy(&tmp16, mc->ptr, 2); 630 mc->ptr += 2; 631 632 cf->can_id = le16_to_cpu(tmp16 >> 5); 633 } 634 635 cf->can_dlc = get_can_dlc(rec_len); 636 637 /* first data packet timestamp is a word */ 638 if (pcan_usb_decode_ts(mc, !mc->rec_data_idx)) 639 goto decode_failed; 640 641 /* read data */ 642 memset(cf->data, 0x0, sizeof(cf->data)); 643 if (status_len & PCAN_USB_STATUSLEN_RTR) { 644 cf->can_id |= CAN_RTR_FLAG; 645 } else { 646 if ((mc->ptr + rec_len) > mc->end) 647 goto decode_failed; 648 649 memcpy(cf->data, mc->ptr, rec_len); 650 mc->ptr += rec_len; 651 } 652 653 /* convert timestamp into kernel time */ 654 peak_usb_get_ts_tv(&mc->pdev->time_ref, mc->ts16, &tv); 655 skb->tstamp = timeval_to_ktime(tv); 656 657 /* push the skb */ 658 netif_rx(skb); 659 660 /* update statistics */ 661 mc->netdev->stats.rx_packets++; 662 mc->netdev->stats.rx_bytes += cf->can_dlc; 663 664 return 0; 665 666 decode_failed: 667 dev_kfree_skb(skb); 668 return -EINVAL; 669 } 670 671 /* 672 * process incoming message 673 */ 674 static int pcan_usb_decode_msg(struct peak_usb_device *dev, u8 *ibuf, u32 lbuf) 675 { 676 struct pcan_usb_msg_context mc = { 677 .rec_cnt = ibuf[1], 678 .ptr = ibuf + PCAN_USB_MSG_HEADER_LEN, 679 .end = ibuf + lbuf, 680 .netdev = dev->netdev, 681 .pdev = container_of(dev, struct pcan_usb, dev), 682 }; 683 int err; 684 685 for (err = 0; mc.rec_idx < mc.rec_cnt && !err; mc.rec_idx++) { 686 u8 sl = *mc.ptr++; 687 688 /* handle status and error frames here */ 689 if (sl & PCAN_USB_STATUSLEN_INTERNAL) { 690 err = pcan_usb_decode_status(&mc, sl); 691 /* handle normal can frames here */ 692 } else { 693 err = pcan_usb_decode_data(&mc, sl); 694 mc.rec_data_idx++; 695 } 696 } 697 698 return err; 699 } 700 701 /* 702 * process any incoming buffer 703 */ 704 static int pcan_usb_decode_buf(struct peak_usb_device *dev, struct urb *urb) 705 { 706 int err = 0; 707 708 if (urb->actual_length > PCAN_USB_MSG_HEADER_LEN) { 709 err = pcan_usb_decode_msg(dev, urb->transfer_buffer, 710 urb->actual_length); 711 712 } else if (urb->actual_length > 0) { 713 netdev_err(dev->netdev, "usb message length error (%u)\n", 714 urb->actual_length); 715 err = -EINVAL; 716 } 717 718 return err; 719 } 720 721 /* 722 * process outgoing packet 723 */ 724 static int pcan_usb_encode_msg(struct peak_usb_device *dev, struct sk_buff *skb, 725 u8 *obuf, size_t *size) 726 { 727 struct net_device *netdev = dev->netdev; 728 struct net_device_stats *stats = &netdev->stats; 729 struct can_frame *cf = (struct can_frame *)skb->data; 730 u8 *pc; 731 732 obuf[0] = 2; 733 obuf[1] = 1; 734 735 pc = obuf + PCAN_USB_MSG_HEADER_LEN; 736 737 /* status/len byte */ 738 *pc = cf->can_dlc; 739 if (cf->can_id & CAN_RTR_FLAG) 740 *pc |= PCAN_USB_STATUSLEN_RTR; 741 742 /* can id */ 743 if (cf->can_id & CAN_EFF_FLAG) { 744 __le32 tmp32 = cpu_to_le32((cf->can_id & CAN_ERR_MASK) << 3); 745 746 *pc |= PCAN_USB_STATUSLEN_EXT_ID; 747 memcpy(++pc, &tmp32, 4); 748 pc += 4; 749 } else { 750 __le16 tmp16 = cpu_to_le16((cf->can_id & CAN_ERR_MASK) << 5); 751 752 memcpy(++pc, &tmp16, 2); 753 pc += 2; 754 } 755 756 /* can data */ 757 if (!(cf->can_id & CAN_RTR_FLAG)) { 758 memcpy(pc, cf->data, cf->can_dlc); 759 pc += cf->can_dlc; 760 } 761 762 obuf[(*size)-1] = (u8)(stats->tx_packets & 0xff); 763 764 return 0; 765 } 766 767 /* 768 * start interface 769 */ 770 static int pcan_usb_start(struct peak_usb_device *dev) 771 { 772 struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev); 773 774 /* number of bits used in timestamps read from adapter struct */ 775 peak_usb_init_time_ref(&pdev->time_ref, &pcan_usb); 776 777 /* if revision greater than 3, can put silent mode on/off */ 778 if (dev->device_rev > 3) { 779 int err; 780 781 err = pcan_usb_set_silent(dev, 782 dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY); 783 if (err) 784 return err; 785 } 786 787 return pcan_usb_set_ext_vcc(dev, 0); 788 } 789 790 static int pcan_usb_init(struct peak_usb_device *dev) 791 { 792 struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev); 793 u32 serial_number; 794 int err; 795 796 /* initialize a timer needed to wait for hardware restart */ 797 init_timer(&pdev->restart_timer); 798 pdev->restart_timer.function = pcan_usb_restart; 799 pdev->restart_timer.data = (unsigned long)dev; 800 801 /* 802 * explicit use of dev_xxx() instead of netdev_xxx() here: 803 * information displayed are related to the device itself, not 804 * to the canx netdevice. 805 */ 806 err = pcan_usb_get_serial(dev, &serial_number); 807 if (err) { 808 dev_err(dev->netdev->dev.parent, 809 "unable to read %s serial number (err %d)\n", 810 pcan_usb.name, err); 811 return err; 812 } 813 814 dev_info(dev->netdev->dev.parent, 815 "PEAK-System %s adapter hwrev %u serial %08X (%u channel)\n", 816 pcan_usb.name, dev->device_rev, serial_number, 817 pcan_usb.ctrl_count); 818 819 return 0; 820 } 821 822 /* 823 * probe function for new PCAN-USB usb interface 824 */ 825 static int pcan_usb_probe(struct usb_interface *intf) 826 { 827 struct usb_host_interface *if_desc; 828 int i; 829 830 if_desc = intf->altsetting; 831 832 /* check interface endpoint addresses */ 833 for (i = 0; i < if_desc->desc.bNumEndpoints; i++) { 834 struct usb_endpoint_descriptor *ep = &if_desc->endpoint[i].desc; 835 836 switch (ep->bEndpointAddress) { 837 case PCAN_USB_EP_CMDOUT: 838 case PCAN_USB_EP_CMDIN: 839 case PCAN_USB_EP_MSGOUT: 840 case PCAN_USB_EP_MSGIN: 841 break; 842 default: 843 return -ENODEV; 844 } 845 } 846 847 return 0; 848 } 849 850 /* 851 * describe the PCAN-USB adapter 852 */ 853 struct peak_usb_adapter pcan_usb = { 854 .name = "PCAN-USB", 855 .device_id = PCAN_USB_PRODUCT_ID, 856 .ctrl_count = 1, 857 .clock = { 858 .freq = PCAN_USB_CRYSTAL_HZ / 2 , 859 }, 860 .bittiming_const = { 861 .name = "pcan_usb", 862 .tseg1_min = 1, 863 .tseg1_max = 16, 864 .tseg2_min = 1, 865 .tseg2_max = 8, 866 .sjw_max = 4, 867 .brp_min = 1, 868 .brp_max = 64, 869 .brp_inc = 1, 870 }, 871 872 /* size of device private data */ 873 .sizeof_dev_private = sizeof(struct pcan_usb), 874 875 /* timestamps usage */ 876 .ts_used_bits = 16, 877 .ts_period = 24575, /* calibration period in ts. */ 878 .us_per_ts_scale = PCAN_USB_TS_US_PER_TICK, /* us=(ts*scale) */ 879 .us_per_ts_shift = PCAN_USB_TS_DIV_SHIFTER, /* >> shift */ 880 881 /* give here messages in/out endpoints */ 882 .ep_msg_in = PCAN_USB_EP_MSGIN, 883 .ep_msg_out = {PCAN_USB_EP_MSGOUT}, 884 885 /* size of rx/tx usb buffers */ 886 .rx_buffer_size = PCAN_USB_RX_BUFFER_SIZE, 887 .tx_buffer_size = PCAN_USB_TX_BUFFER_SIZE, 888 889 /* device callbacks */ 890 .intf_probe = pcan_usb_probe, 891 .dev_init = pcan_usb_init, 892 .dev_set_bus = pcan_usb_write_mode, 893 .dev_set_bittiming = pcan_usb_set_bittiming, 894 .dev_get_device_id = pcan_usb_get_device_id, 895 .dev_decode_buf = pcan_usb_decode_buf, 896 .dev_encode_msg = pcan_usb_encode_msg, 897 .dev_start = pcan_usb_start, 898 .dev_restart_async = pcan_usb_restart_async, 899 }; 900