1 /* 2 * Copyright (C) 2007, 2011 Wolfgang Grandegger <wg@grandegger.com> 3 * Copyright (C) 2012 Stephane Grosjean <s.grosjean@peak-system.com> 4 * 5 * Copyright (C) 2016 PEAK System-Technik GmbH 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the version 2 of the GNU General Public License 9 * as published by the Free Software Foundation 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 */ 16 17 #include <linux/can.h> 18 #include <linux/can/dev.h> 19 20 #include "peak_canfd_user.h" 21 22 /* internal IP core cache size (used as default echo skbs max number) */ 23 #define PCANFD_ECHO_SKB_MAX 24 24 25 /* bittiming ranges of the PEAK-System PC CAN-FD interfaces */ 26 static const struct can_bittiming_const peak_canfd_nominal_const = { 27 .name = "peak_canfd", 28 .tseg1_min = 1, 29 .tseg1_max = (1 << PUCAN_TSLOW_TSGEG1_BITS), 30 .tseg2_min = 1, 31 .tseg2_max = (1 << PUCAN_TSLOW_TSGEG2_BITS), 32 .sjw_max = (1 << PUCAN_TSLOW_SJW_BITS), 33 .brp_min = 1, 34 .brp_max = (1 << PUCAN_TSLOW_BRP_BITS), 35 .brp_inc = 1, 36 }; 37 38 static const struct can_bittiming_const peak_canfd_data_const = { 39 .name = "peak_canfd", 40 .tseg1_min = 1, 41 .tseg1_max = (1 << PUCAN_TFAST_TSGEG1_BITS), 42 .tseg2_min = 1, 43 .tseg2_max = (1 << PUCAN_TFAST_TSGEG2_BITS), 44 .sjw_max = (1 << PUCAN_TFAST_SJW_BITS), 45 .brp_min = 1, 46 .brp_max = (1 << PUCAN_TFAST_BRP_BITS), 47 .brp_inc = 1, 48 }; 49 50 static struct peak_canfd_priv *pucan_init_cmd(struct peak_canfd_priv *priv) 51 { 52 priv->cmd_len = 0; 53 return priv; 54 } 55 56 static void *pucan_add_cmd(struct peak_canfd_priv *priv, int cmd_op) 57 { 58 struct pucan_command *cmd; 59 60 if (priv->cmd_len + sizeof(*cmd) > priv->cmd_maxlen) 61 return NULL; 62 63 cmd = priv->cmd_buffer + priv->cmd_len; 64 65 /* reset all unused bit to default */ 66 memset(cmd, 0, sizeof(*cmd)); 67 68 cmd->opcode_channel = pucan_cmd_opcode_channel(priv->index, cmd_op); 69 priv->cmd_len += sizeof(*cmd); 70 71 return cmd; 72 } 73 74 static int pucan_write_cmd(struct peak_canfd_priv *priv) 75 { 76 int err; 77 78 if (priv->pre_cmd) { 79 err = priv->pre_cmd(priv); 80 if (err) 81 return err; 82 } 83 84 err = priv->write_cmd(priv); 85 if (err) 86 return err; 87 88 if (priv->post_cmd) 89 err = priv->post_cmd(priv); 90 91 return err; 92 } 93 94 /* uCAN commands interface functions */ 95 static int pucan_set_reset_mode(struct peak_canfd_priv *priv) 96 { 97 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_RESET_MODE); 98 return pucan_write_cmd(priv); 99 } 100 101 static int pucan_set_normal_mode(struct peak_canfd_priv *priv) 102 { 103 int err; 104 105 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_NORMAL_MODE); 106 err = pucan_write_cmd(priv); 107 if (!err) 108 priv->can.state = CAN_STATE_ERROR_ACTIVE; 109 110 return err; 111 } 112 113 static int pucan_set_listen_only_mode(struct peak_canfd_priv *priv) 114 { 115 int err; 116 117 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_LISTEN_ONLY_MODE); 118 err = pucan_write_cmd(priv); 119 if (!err) 120 priv->can.state = CAN_STATE_ERROR_ACTIVE; 121 122 return err; 123 } 124 125 static int pucan_set_timing_slow(struct peak_canfd_priv *priv, 126 const struct can_bittiming *pbt) 127 { 128 struct pucan_timing_slow *cmd; 129 130 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_TIMING_SLOW); 131 132 cmd->sjw_t = PUCAN_TSLOW_SJW_T(pbt->sjw - 1, 133 priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES); 134 cmd->tseg1 = PUCAN_TSLOW_TSEG1(pbt->prop_seg + pbt->phase_seg1 - 1); 135 cmd->tseg2 = PUCAN_TSLOW_TSEG2(pbt->phase_seg2 - 1); 136 cmd->brp = cpu_to_le16(PUCAN_TSLOW_BRP(pbt->brp - 1)); 137 138 cmd->ewl = 96; /* default */ 139 140 netdev_dbg(priv->ndev, 141 "nominal: brp=%u tseg1=%u tseg2=%u sjw=%u\n", 142 le16_to_cpu(cmd->brp), cmd->tseg1, cmd->tseg2, cmd->sjw_t); 143 144 return pucan_write_cmd(priv); 145 } 146 147 static int pucan_set_timing_fast(struct peak_canfd_priv *priv, 148 const struct can_bittiming *pbt) 149 { 150 struct pucan_timing_fast *cmd; 151 152 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_TIMING_FAST); 153 154 cmd->sjw = PUCAN_TFAST_SJW(pbt->sjw - 1); 155 cmd->tseg1 = PUCAN_TFAST_TSEG1(pbt->prop_seg + pbt->phase_seg1 - 1); 156 cmd->tseg2 = PUCAN_TFAST_TSEG2(pbt->phase_seg2 - 1); 157 cmd->brp = cpu_to_le16(PUCAN_TFAST_BRP(pbt->brp - 1)); 158 159 netdev_dbg(priv->ndev, 160 "data: brp=%u tseg1=%u tseg2=%u sjw=%u\n", 161 le16_to_cpu(cmd->brp), cmd->tseg1, cmd->tseg2, cmd->sjw); 162 163 return pucan_write_cmd(priv); 164 } 165 166 static int pucan_set_std_filter(struct peak_canfd_priv *priv, u8 row, u32 mask) 167 { 168 struct pucan_std_filter *cmd; 169 170 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_SET_STD_FILTER); 171 172 /* all the 11-bits CAN ID values are represented by one bit in a 173 * 64 rows array of 32 bits: the upper 6 bits of the CAN ID select the 174 * row while the lowest 5 bits select the bit in that row. 175 * 176 * bit filter 177 * 1 passed 178 * 0 discarded 179 */ 180 181 /* select the row */ 182 cmd->idx = row; 183 184 /* set/unset bits in the row */ 185 cmd->mask = cpu_to_le32(mask); 186 187 return pucan_write_cmd(priv); 188 } 189 190 static int pucan_tx_abort(struct peak_canfd_priv *priv, u16 flags) 191 { 192 struct pucan_tx_abort *cmd; 193 194 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_TX_ABORT); 195 196 cmd->flags = cpu_to_le16(flags); 197 198 return pucan_write_cmd(priv); 199 } 200 201 static int pucan_clr_err_counters(struct peak_canfd_priv *priv) 202 { 203 struct pucan_wr_err_cnt *cmd; 204 205 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_WR_ERR_CNT); 206 207 cmd->sel_mask = cpu_to_le16(PUCAN_WRERRCNT_TE | PUCAN_WRERRCNT_RE); 208 cmd->tx_counter = 0; 209 cmd->rx_counter = 0; 210 211 return pucan_write_cmd(priv); 212 } 213 214 static int pucan_set_options(struct peak_canfd_priv *priv, u16 opt_mask) 215 { 216 struct pucan_options *cmd; 217 218 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_SET_EN_OPTION); 219 220 cmd->options = cpu_to_le16(opt_mask); 221 222 return pucan_write_cmd(priv); 223 } 224 225 static int pucan_clr_options(struct peak_canfd_priv *priv, u16 opt_mask) 226 { 227 struct pucan_options *cmd; 228 229 cmd = pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_CLR_DIS_OPTION); 230 231 cmd->options = cpu_to_le16(opt_mask); 232 233 return pucan_write_cmd(priv); 234 } 235 236 static int pucan_setup_rx_barrier(struct peak_canfd_priv *priv) 237 { 238 pucan_add_cmd(pucan_init_cmd(priv), PUCAN_CMD_RX_BARRIER); 239 240 return pucan_write_cmd(priv); 241 } 242 243 /* handle the reception of one CAN frame */ 244 static int pucan_handle_can_rx(struct peak_canfd_priv *priv, 245 struct pucan_rx_msg *msg) 246 { 247 struct net_device_stats *stats = &priv->ndev->stats; 248 struct canfd_frame *cf; 249 struct sk_buff *skb; 250 const u16 rx_msg_flags = le16_to_cpu(msg->flags); 251 u8 cf_len; 252 253 if (rx_msg_flags & PUCAN_MSG_EXT_DATA_LEN) 254 cf_len = can_dlc2len(get_canfd_dlc(pucan_msg_get_dlc(msg))); 255 else 256 cf_len = get_can_dlc(pucan_msg_get_dlc(msg)); 257 258 /* if this frame is an echo, */ 259 if ((rx_msg_flags & PUCAN_MSG_LOOPED_BACK) && 260 !(rx_msg_flags & PUCAN_MSG_SELF_RECEIVE)) { 261 int n; 262 unsigned long flags; 263 264 spin_lock_irqsave(&priv->echo_lock, flags); 265 n = can_get_echo_skb(priv->ndev, msg->client); 266 spin_unlock_irqrestore(&priv->echo_lock, flags); 267 268 /* count bytes of the echo instead of skb */ 269 stats->tx_bytes += cf_len; 270 stats->tx_packets++; 271 272 if (n) { 273 /* restart tx queue only if a slot is free */ 274 netif_wake_queue(priv->ndev); 275 } 276 277 return 0; 278 } 279 280 /* otherwise, it should be pushed into rx fifo */ 281 if (rx_msg_flags & PUCAN_MSG_EXT_DATA_LEN) { 282 /* CANFD frame case */ 283 skb = alloc_canfd_skb(priv->ndev, &cf); 284 if (!skb) 285 return -ENOMEM; 286 287 if (rx_msg_flags & PUCAN_MSG_BITRATE_SWITCH) 288 cf->flags |= CANFD_BRS; 289 290 if (rx_msg_flags & PUCAN_MSG_ERROR_STATE_IND) 291 cf->flags |= CANFD_ESI; 292 } else { 293 /* CAN 2.0 frame case */ 294 skb = alloc_can_skb(priv->ndev, (struct can_frame **)&cf); 295 if (!skb) 296 return -ENOMEM; 297 } 298 299 cf->can_id = le32_to_cpu(msg->can_id); 300 cf->len = cf_len; 301 302 if (rx_msg_flags & PUCAN_MSG_EXT_ID) 303 cf->can_id |= CAN_EFF_FLAG; 304 305 if (rx_msg_flags & PUCAN_MSG_RTR) 306 cf->can_id |= CAN_RTR_FLAG; 307 else 308 memcpy(cf->data, msg->d, cf->len); 309 310 stats->rx_bytes += cf->len; 311 stats->rx_packets++; 312 313 netif_rx(skb); 314 315 return 0; 316 } 317 318 /* handle rx/tx error counters notification */ 319 static int pucan_handle_error(struct peak_canfd_priv *priv, 320 struct pucan_error_msg *msg) 321 { 322 priv->bec.txerr = msg->tx_err_cnt; 323 priv->bec.rxerr = msg->rx_err_cnt; 324 325 return 0; 326 } 327 328 /* handle status notification */ 329 static int pucan_handle_status(struct peak_canfd_priv *priv, 330 struct pucan_status_msg *msg) 331 { 332 struct net_device *ndev = priv->ndev; 333 struct net_device_stats *stats = &ndev->stats; 334 struct can_frame *cf; 335 struct sk_buff *skb; 336 337 /* this STATUS is the CNF of the RX_BARRIER: Tx path can be setup */ 338 if (pucan_status_is_rx_barrier(msg)) { 339 unsigned long flags; 340 341 if (priv->enable_tx_path) { 342 int err = priv->enable_tx_path(priv); 343 344 if (err) 345 return err; 346 } 347 348 /* restart network queue only if echo skb array is free */ 349 spin_lock_irqsave(&priv->echo_lock, flags); 350 351 if (!priv->can.echo_skb[priv->echo_idx]) { 352 spin_unlock_irqrestore(&priv->echo_lock, flags); 353 354 netif_wake_queue(ndev); 355 } else { 356 spin_unlock_irqrestore(&priv->echo_lock, flags); 357 } 358 359 return 0; 360 } 361 362 skb = alloc_can_err_skb(ndev, &cf); 363 364 /* test state error bits according to their priority */ 365 if (pucan_status_is_busoff(msg)) { 366 netdev_dbg(ndev, "Bus-off entry status\n"); 367 priv->can.state = CAN_STATE_BUS_OFF; 368 priv->can.can_stats.bus_off++; 369 can_bus_off(ndev); 370 if (skb) 371 cf->can_id |= CAN_ERR_BUSOFF; 372 373 } else if (pucan_status_is_passive(msg)) { 374 netdev_dbg(ndev, "Error passive status\n"); 375 priv->can.state = CAN_STATE_ERROR_PASSIVE; 376 priv->can.can_stats.error_passive++; 377 if (skb) { 378 cf->can_id |= CAN_ERR_CRTL; 379 cf->data[1] = (priv->bec.txerr > priv->bec.rxerr) ? 380 CAN_ERR_CRTL_TX_PASSIVE : 381 CAN_ERR_CRTL_RX_PASSIVE; 382 cf->data[6] = priv->bec.txerr; 383 cf->data[7] = priv->bec.rxerr; 384 } 385 386 } else if (pucan_status_is_warning(msg)) { 387 netdev_dbg(ndev, "Error warning status\n"); 388 priv->can.state = CAN_STATE_ERROR_WARNING; 389 priv->can.can_stats.error_warning++; 390 if (skb) { 391 cf->can_id |= CAN_ERR_CRTL; 392 cf->data[1] = (priv->bec.txerr > priv->bec.rxerr) ? 393 CAN_ERR_CRTL_TX_WARNING : 394 CAN_ERR_CRTL_RX_WARNING; 395 cf->data[6] = priv->bec.txerr; 396 cf->data[7] = priv->bec.rxerr; 397 } 398 399 } else if (priv->can.state != CAN_STATE_ERROR_ACTIVE) { 400 /* back to ERROR_ACTIVE */ 401 netdev_dbg(ndev, "Error active status\n"); 402 can_change_state(ndev, cf, CAN_STATE_ERROR_ACTIVE, 403 CAN_STATE_ERROR_ACTIVE); 404 } else { 405 dev_kfree_skb(skb); 406 return 0; 407 } 408 409 if (!skb) { 410 stats->rx_dropped++; 411 return -ENOMEM; 412 } 413 414 stats->rx_packets++; 415 stats->rx_bytes += cf->can_dlc; 416 netif_rx(skb); 417 418 return 0; 419 } 420 421 /* handle uCAN Rx overflow notification */ 422 static int pucan_handle_cache_critical(struct peak_canfd_priv *priv) 423 { 424 struct net_device_stats *stats = &priv->ndev->stats; 425 struct can_frame *cf; 426 struct sk_buff *skb; 427 428 stats->rx_over_errors++; 429 stats->rx_errors++; 430 431 skb = alloc_can_err_skb(priv->ndev, &cf); 432 if (!skb) { 433 stats->rx_dropped++; 434 return -ENOMEM; 435 } 436 437 cf->can_id |= CAN_ERR_CRTL; 438 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 439 440 cf->data[6] = priv->bec.txerr; 441 cf->data[7] = priv->bec.rxerr; 442 443 stats->rx_bytes += cf->can_dlc; 444 stats->rx_packets++; 445 netif_rx(skb); 446 447 return 0; 448 } 449 450 /* handle a single uCAN message */ 451 int peak_canfd_handle_msg(struct peak_canfd_priv *priv, 452 struct pucan_rx_msg *msg) 453 { 454 u16 msg_type = le16_to_cpu(msg->type); 455 int msg_size = le16_to_cpu(msg->size); 456 int err; 457 458 if (!msg_size || !msg_type) { 459 /* null packet found: end of list */ 460 goto exit; 461 } 462 463 switch (msg_type) { 464 case PUCAN_MSG_CAN_RX: 465 err = pucan_handle_can_rx(priv, (struct pucan_rx_msg *)msg); 466 break; 467 case PUCAN_MSG_ERROR: 468 err = pucan_handle_error(priv, (struct pucan_error_msg *)msg); 469 break; 470 case PUCAN_MSG_STATUS: 471 err = pucan_handle_status(priv, (struct pucan_status_msg *)msg); 472 break; 473 case PUCAN_MSG_CACHE_CRITICAL: 474 err = pucan_handle_cache_critical(priv); 475 break; 476 default: 477 err = 0; 478 } 479 480 if (err < 0) 481 return err; 482 483 exit: 484 return msg_size; 485 } 486 487 /* handle a list of rx_count messages from rx_msg memory address */ 488 int peak_canfd_handle_msgs_list(struct peak_canfd_priv *priv, 489 struct pucan_rx_msg *msg_list, int msg_count) 490 { 491 void *msg_ptr = msg_list; 492 int i, msg_size; 493 494 for (i = 0; i < msg_count; i++) { 495 msg_size = peak_canfd_handle_msg(priv, msg_ptr); 496 497 /* a null packet can be found at the end of a list */ 498 if (msg_size <= 0) 499 break; 500 501 msg_ptr += msg_size; 502 } 503 504 if (msg_size < 0) 505 return msg_size; 506 507 return i; 508 } 509 510 static int peak_canfd_start(struct peak_canfd_priv *priv) 511 { 512 int err; 513 514 err = pucan_clr_err_counters(priv); 515 if (err) 516 goto err_exit; 517 518 priv->echo_idx = 0; 519 520 priv->bec.txerr = 0; 521 priv->bec.rxerr = 0; 522 523 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) 524 err = pucan_set_listen_only_mode(priv); 525 else 526 err = pucan_set_normal_mode(priv); 527 528 err_exit: 529 return err; 530 } 531 532 static void peak_canfd_stop(struct peak_canfd_priv *priv) 533 { 534 int err; 535 536 /* go back to RESET mode */ 537 err = pucan_set_reset_mode(priv); 538 if (err) { 539 netdev_err(priv->ndev, "channel %u reset failed\n", 540 priv->index); 541 } else { 542 /* abort last Tx (MUST be done in RESET mode only!) */ 543 pucan_tx_abort(priv, PUCAN_TX_ABORT_FLUSH); 544 } 545 } 546 547 static int peak_canfd_set_mode(struct net_device *ndev, enum can_mode mode) 548 { 549 struct peak_canfd_priv *priv = netdev_priv(ndev); 550 551 switch (mode) { 552 case CAN_MODE_START: 553 peak_canfd_start(priv); 554 netif_wake_queue(ndev); 555 break; 556 default: 557 return -EOPNOTSUPP; 558 } 559 560 return 0; 561 } 562 563 static int peak_canfd_get_berr_counter(const struct net_device *ndev, 564 struct can_berr_counter *bec) 565 { 566 struct peak_canfd_priv *priv = netdev_priv(ndev); 567 568 *bec = priv->bec; 569 return 0; 570 } 571 572 static int peak_canfd_open(struct net_device *ndev) 573 { 574 struct peak_canfd_priv *priv = netdev_priv(ndev); 575 int i, err = 0; 576 577 err = open_candev(ndev); 578 if (err) { 579 netdev_err(ndev, "open_candev() failed, error %d\n", err); 580 goto err_exit; 581 } 582 583 err = pucan_set_reset_mode(priv); 584 if (err) 585 goto err_close; 586 587 if (priv->can.ctrlmode & CAN_CTRLMODE_FD) { 588 if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO) 589 err = pucan_clr_options(priv, PUCAN_OPTION_CANDFDISO); 590 else 591 err = pucan_set_options(priv, PUCAN_OPTION_CANDFDISO); 592 593 if (err) 594 goto err_close; 595 } 596 597 /* set option: get rx/tx error counters */ 598 err = pucan_set_options(priv, PUCAN_OPTION_ERROR); 599 if (err) 600 goto err_close; 601 602 /* accept all standard CAN ID */ 603 for (i = 0; i <= PUCAN_FLTSTD_ROW_IDX_MAX; i++) 604 pucan_set_std_filter(priv, i, 0xffffffff); 605 606 err = peak_canfd_start(priv); 607 if (err) 608 goto err_close; 609 610 /* receiving the RB status says when Tx path is ready */ 611 err = pucan_setup_rx_barrier(priv); 612 if (!err) 613 goto err_exit; 614 615 err_close: 616 close_candev(ndev); 617 err_exit: 618 return err; 619 } 620 621 static int peak_canfd_set_bittiming(struct net_device *ndev) 622 { 623 struct peak_canfd_priv *priv = netdev_priv(ndev); 624 625 return pucan_set_timing_slow(priv, &priv->can.bittiming); 626 } 627 628 static int peak_canfd_set_data_bittiming(struct net_device *ndev) 629 { 630 struct peak_canfd_priv *priv = netdev_priv(ndev); 631 632 return pucan_set_timing_fast(priv, &priv->can.data_bittiming); 633 } 634 635 static int peak_canfd_close(struct net_device *ndev) 636 { 637 struct peak_canfd_priv *priv = netdev_priv(ndev); 638 639 netif_stop_queue(ndev); 640 peak_canfd_stop(priv); 641 close_candev(ndev); 642 643 return 0; 644 } 645 646 static netdev_tx_t peak_canfd_start_xmit(struct sk_buff *skb, 647 struct net_device *ndev) 648 { 649 struct peak_canfd_priv *priv = netdev_priv(ndev); 650 struct net_device_stats *stats = &ndev->stats; 651 struct canfd_frame *cf = (struct canfd_frame *)skb->data; 652 struct pucan_tx_msg *msg; 653 u16 msg_size, msg_flags; 654 unsigned long flags; 655 bool should_stop_tx_queue; 656 int room_left; 657 u8 can_dlc; 658 659 if (can_dropped_invalid_skb(ndev, skb)) 660 return NETDEV_TX_OK; 661 662 msg_size = ALIGN(sizeof(*msg) + cf->len, 4); 663 msg = priv->alloc_tx_msg(priv, msg_size, &room_left); 664 665 /* should never happen except under bus-off condition and (auto-)restart 666 * mechanism 667 */ 668 if (!msg) { 669 stats->tx_dropped++; 670 netif_stop_queue(ndev); 671 return NETDEV_TX_BUSY; 672 } 673 674 msg->size = cpu_to_le16(msg_size); 675 msg->type = cpu_to_le16(PUCAN_MSG_CAN_TX); 676 msg_flags = 0; 677 678 if (cf->can_id & CAN_EFF_FLAG) { 679 msg_flags |= PUCAN_MSG_EXT_ID; 680 msg->can_id = cpu_to_le32(cf->can_id & CAN_EFF_MASK); 681 } else { 682 msg->can_id = cpu_to_le32(cf->can_id & CAN_SFF_MASK); 683 } 684 685 if (can_is_canfd_skb(skb)) { 686 /* CAN FD frame format */ 687 can_dlc = can_len2dlc(cf->len); 688 689 msg_flags |= PUCAN_MSG_EXT_DATA_LEN; 690 691 if (cf->flags & CANFD_BRS) 692 msg_flags |= PUCAN_MSG_BITRATE_SWITCH; 693 694 if (cf->flags & CANFD_ESI) 695 msg_flags |= PUCAN_MSG_ERROR_STATE_IND; 696 } else { 697 /* CAN 2.0 frame format */ 698 can_dlc = cf->len; 699 700 if (cf->can_id & CAN_RTR_FLAG) 701 msg_flags |= PUCAN_MSG_RTR; 702 } 703 704 /* always ask loopback for echo management */ 705 msg_flags |= PUCAN_MSG_LOOPED_BACK; 706 707 /* set driver specific bit to differentiate with application loopback */ 708 if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) 709 msg_flags |= PUCAN_MSG_SELF_RECEIVE; 710 711 msg->flags = cpu_to_le16(msg_flags); 712 msg->channel_dlc = PUCAN_MSG_CHANNEL_DLC(priv->index, can_dlc); 713 memcpy(msg->d, cf->data, cf->len); 714 715 /* struct msg client field is used as an index in the echo skbs ring */ 716 msg->client = priv->echo_idx; 717 718 spin_lock_irqsave(&priv->echo_lock, flags); 719 720 /* prepare and save echo skb in internal slot */ 721 can_put_echo_skb(skb, ndev, priv->echo_idx); 722 723 /* move echo index to the next slot */ 724 priv->echo_idx = (priv->echo_idx + 1) % priv->can.echo_skb_max; 725 726 /* if next slot is not free, stop network queue (no slot free in echo 727 * skb ring means that the controller did not write these frames on 728 * the bus: no need to continue). 729 */ 730 should_stop_tx_queue = !!(priv->can.echo_skb[priv->echo_idx]); 731 732 spin_unlock_irqrestore(&priv->echo_lock, flags); 733 734 /* write the skb on the interface */ 735 priv->write_tx_msg(priv, msg); 736 737 /* stop network tx queue if not enough room to save one more msg too */ 738 if (priv->can.ctrlmode & CAN_CTRLMODE_FD) 739 should_stop_tx_queue |= (room_left < 740 (sizeof(*msg) + CANFD_MAX_DLEN)); 741 else 742 should_stop_tx_queue |= (room_left < 743 (sizeof(*msg) + CAN_MAX_DLEN)); 744 745 if (should_stop_tx_queue) 746 netif_stop_queue(ndev); 747 748 return NETDEV_TX_OK; 749 } 750 751 static const struct net_device_ops peak_canfd_netdev_ops = { 752 .ndo_open = peak_canfd_open, 753 .ndo_stop = peak_canfd_close, 754 .ndo_start_xmit = peak_canfd_start_xmit, 755 .ndo_change_mtu = can_change_mtu, 756 }; 757 758 struct net_device *alloc_peak_canfd_dev(int sizeof_priv, int index, 759 int echo_skb_max) 760 { 761 struct net_device *ndev; 762 struct peak_canfd_priv *priv; 763 764 /* we DO support local echo */ 765 if (echo_skb_max < 0) 766 echo_skb_max = PCANFD_ECHO_SKB_MAX; 767 768 /* allocate the candev object */ 769 ndev = alloc_candev(sizeof_priv, echo_skb_max); 770 if (!ndev) 771 return NULL; 772 773 priv = netdev_priv(ndev); 774 775 /* complete now socket-can initialization side */ 776 priv->can.state = CAN_STATE_STOPPED; 777 priv->can.bittiming_const = &peak_canfd_nominal_const; 778 priv->can.data_bittiming_const = &peak_canfd_data_const; 779 780 priv->can.do_set_mode = peak_canfd_set_mode; 781 priv->can.do_get_berr_counter = peak_canfd_get_berr_counter; 782 priv->can.do_set_bittiming = peak_canfd_set_bittiming; 783 priv->can.do_set_data_bittiming = peak_canfd_set_data_bittiming; 784 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | 785 CAN_CTRLMODE_LISTENONLY | 786 CAN_CTRLMODE_3_SAMPLES | 787 CAN_CTRLMODE_FD | 788 CAN_CTRLMODE_FD_NON_ISO | 789 CAN_CTRLMODE_BERR_REPORTING; 790 791 priv->ndev = ndev; 792 priv->index = index; 793 priv->cmd_len = 0; 794 spin_lock_init(&priv->echo_lock); 795 796 ndev->flags |= IFF_ECHO; 797 ndev->netdev_ops = &peak_canfd_netdev_ops; 798 ndev->dev_id = index; 799 800 return ndev; 801 } 802