1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * CAN bus driver for the alone generic (as possible as) MSCAN controller. 4 * 5 * Copyright (C) 2005-2006 Andrey Volkov <avolkov@varma-el.com>, 6 * Varma Electronics Oy 7 * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com> 8 * Copyright (C) 2008-2009 Pengutronix <kernel@pengutronix.de> 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/interrupt.h> 14 #include <linux/delay.h> 15 #include <linux/netdevice.h> 16 #include <linux/if_arp.h> 17 #include <linux/if_ether.h> 18 #include <linux/list.h> 19 #include <linux/can/dev.h> 20 #include <linux/can/error.h> 21 #include <linux/io.h> 22 23 #include "mscan.h" 24 25 static const struct can_bittiming_const mscan_bittiming_const = { 26 .name = "mscan", 27 .tseg1_min = 4, 28 .tseg1_max = 16, 29 .tseg2_min = 2, 30 .tseg2_max = 8, 31 .sjw_max = 4, 32 .brp_min = 1, 33 .brp_max = 64, 34 .brp_inc = 1, 35 }; 36 37 struct mscan_state { 38 u8 mode; 39 u8 canrier; 40 u8 cantier; 41 }; 42 43 static enum can_state state_map[] = { 44 CAN_STATE_ERROR_ACTIVE, 45 CAN_STATE_ERROR_WARNING, 46 CAN_STATE_ERROR_PASSIVE, 47 CAN_STATE_BUS_OFF 48 }; 49 50 static int mscan_set_mode(struct net_device *dev, u8 mode) 51 { 52 struct mscan_priv *priv = netdev_priv(dev); 53 struct mscan_regs __iomem *regs = priv->reg_base; 54 int ret = 0; 55 int i; 56 u8 canctl1; 57 58 if (mode != MSCAN_NORMAL_MODE) { 59 if (priv->tx_active) { 60 /* Abort transfers before going to sleep */# 61 out_8(®s->cantarq, priv->tx_active); 62 /* Suppress TX done interrupts */ 63 out_8(®s->cantier, 0); 64 } 65 66 canctl1 = in_8(®s->canctl1); 67 if ((mode & MSCAN_SLPRQ) && !(canctl1 & MSCAN_SLPAK)) { 68 setbits8(®s->canctl0, MSCAN_SLPRQ); 69 for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) { 70 if (in_8(®s->canctl1) & MSCAN_SLPAK) 71 break; 72 udelay(100); 73 } 74 /* 75 * The mscan controller will fail to enter sleep mode, 76 * while there are irregular activities on bus, like 77 * somebody keeps retransmitting. This behavior is 78 * undocumented and seems to differ between mscan built 79 * in mpc5200b and mpc5200. We proceed in that case, 80 * since otherwise the slprq will be kept set and the 81 * controller will get stuck. NOTE: INITRQ or CSWAI 82 * will abort all active transmit actions, if still 83 * any, at once. 84 */ 85 if (i >= MSCAN_SET_MODE_RETRIES) 86 netdev_dbg(dev, 87 "device failed to enter sleep mode. " 88 "We proceed anyhow.\n"); 89 else 90 priv->can.state = CAN_STATE_SLEEPING; 91 } 92 93 if ((mode & MSCAN_INITRQ) && !(canctl1 & MSCAN_INITAK)) { 94 setbits8(®s->canctl0, MSCAN_INITRQ); 95 for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) { 96 if (in_8(®s->canctl1) & MSCAN_INITAK) 97 break; 98 } 99 if (i >= MSCAN_SET_MODE_RETRIES) 100 ret = -ENODEV; 101 } 102 if (!ret) 103 priv->can.state = CAN_STATE_STOPPED; 104 105 if (mode & MSCAN_CSWAI) 106 setbits8(®s->canctl0, MSCAN_CSWAI); 107 108 } else { 109 canctl1 = in_8(®s->canctl1); 110 if (canctl1 & (MSCAN_SLPAK | MSCAN_INITAK)) { 111 clrbits8(®s->canctl0, MSCAN_SLPRQ | MSCAN_INITRQ); 112 for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) { 113 canctl1 = in_8(®s->canctl1); 114 if (!(canctl1 & (MSCAN_INITAK | MSCAN_SLPAK))) 115 break; 116 } 117 if (i >= MSCAN_SET_MODE_RETRIES) 118 ret = -ENODEV; 119 else 120 priv->can.state = CAN_STATE_ERROR_ACTIVE; 121 } 122 } 123 return ret; 124 } 125 126 static int mscan_start(struct net_device *dev) 127 { 128 struct mscan_priv *priv = netdev_priv(dev); 129 struct mscan_regs __iomem *regs = priv->reg_base; 130 u8 canrflg; 131 int err; 132 133 out_8(®s->canrier, 0); 134 135 INIT_LIST_HEAD(&priv->tx_head); 136 priv->prev_buf_id = 0; 137 priv->cur_pri = 0; 138 priv->tx_active = 0; 139 priv->shadow_canrier = 0; 140 priv->flags = 0; 141 142 if (priv->type == MSCAN_TYPE_MPC5121) { 143 /* Clear pending bus-off condition */ 144 if (in_8(®s->canmisc) & MSCAN_BOHOLD) 145 out_8(®s->canmisc, MSCAN_BOHOLD); 146 } 147 148 err = mscan_set_mode(dev, MSCAN_NORMAL_MODE); 149 if (err) 150 return err; 151 152 canrflg = in_8(®s->canrflg); 153 priv->shadow_statflg = canrflg & MSCAN_STAT_MSK; 154 priv->can.state = state_map[max(MSCAN_STATE_RX(canrflg), 155 MSCAN_STATE_TX(canrflg))]; 156 out_8(®s->cantier, 0); 157 158 /* Enable receive interrupts. */ 159 out_8(®s->canrier, MSCAN_RX_INTS_ENABLE); 160 161 return 0; 162 } 163 164 static int mscan_restart(struct net_device *dev) 165 { 166 struct mscan_priv *priv = netdev_priv(dev); 167 168 if (priv->type == MSCAN_TYPE_MPC5121) { 169 struct mscan_regs __iomem *regs = priv->reg_base; 170 171 priv->can.state = CAN_STATE_ERROR_ACTIVE; 172 WARN(!(in_8(®s->canmisc) & MSCAN_BOHOLD), 173 "bus-off state expected\n"); 174 out_8(®s->canmisc, MSCAN_BOHOLD); 175 /* Re-enable receive interrupts. */ 176 out_8(®s->canrier, MSCAN_RX_INTS_ENABLE); 177 } else { 178 if (priv->can.state <= CAN_STATE_BUS_OFF) 179 mscan_set_mode(dev, MSCAN_INIT_MODE); 180 return mscan_start(dev); 181 } 182 183 return 0; 184 } 185 186 static netdev_tx_t mscan_start_xmit(struct sk_buff *skb, struct net_device *dev) 187 { 188 struct can_frame *frame = (struct can_frame *)skb->data; 189 struct mscan_priv *priv = netdev_priv(dev); 190 struct mscan_regs __iomem *regs = priv->reg_base; 191 int i, rtr, buf_id; 192 u32 can_id; 193 194 if (can_dropped_invalid_skb(dev, skb)) 195 return NETDEV_TX_OK; 196 197 out_8(®s->cantier, 0); 198 199 i = ~priv->tx_active & MSCAN_TXE; 200 buf_id = ffs(i) - 1; 201 switch (hweight8(i)) { 202 case 0: 203 netif_stop_queue(dev); 204 netdev_err(dev, "Tx Ring full when queue awake!\n"); 205 return NETDEV_TX_BUSY; 206 case 1: 207 /* 208 * if buf_id < 3, then current frame will be send out of order, 209 * since buffer with lower id have higher priority (hell..) 210 */ 211 netif_stop_queue(dev); 212 fallthrough; 213 case 2: 214 if (buf_id < priv->prev_buf_id) { 215 priv->cur_pri++; 216 if (priv->cur_pri == 0xff) { 217 set_bit(F_TX_WAIT_ALL, &priv->flags); 218 netif_stop_queue(dev); 219 } 220 } 221 set_bit(F_TX_PROGRESS, &priv->flags); 222 break; 223 } 224 priv->prev_buf_id = buf_id; 225 out_8(®s->cantbsel, i); 226 227 rtr = frame->can_id & CAN_RTR_FLAG; 228 229 /* RTR is always the lowest bit of interest, then IDs follow */ 230 if (frame->can_id & CAN_EFF_FLAG) { 231 can_id = (frame->can_id & CAN_EFF_MASK) 232 << (MSCAN_EFF_RTR_SHIFT + 1); 233 if (rtr) 234 can_id |= 1 << MSCAN_EFF_RTR_SHIFT; 235 out_be16(®s->tx.idr3_2, can_id); 236 237 can_id >>= 16; 238 /* EFF_FLAGS are between the IDs :( */ 239 can_id = (can_id & 0x7) | ((can_id << 2) & 0xffe0) 240 | MSCAN_EFF_FLAGS; 241 } else { 242 can_id = (frame->can_id & CAN_SFF_MASK) 243 << (MSCAN_SFF_RTR_SHIFT + 1); 244 if (rtr) 245 can_id |= 1 << MSCAN_SFF_RTR_SHIFT; 246 } 247 out_be16(®s->tx.idr1_0, can_id); 248 249 if (!rtr) { 250 void __iomem *data = ®s->tx.dsr1_0; 251 u16 *payload = (u16 *)frame->data; 252 253 for (i = 0; i < frame->len / 2; i++) { 254 out_be16(data, *payload++); 255 data += 2 + _MSCAN_RESERVED_DSR_SIZE; 256 } 257 /* write remaining byte if necessary */ 258 if (frame->len & 1) 259 out_8(data, frame->data[frame->len - 1]); 260 } 261 262 out_8(®s->tx.dlr, frame->len); 263 out_8(®s->tx.tbpr, priv->cur_pri); 264 265 /* Start transmission. */ 266 out_8(®s->cantflg, 1 << buf_id); 267 268 if (!test_bit(F_TX_PROGRESS, &priv->flags)) 269 netif_trans_update(dev); 270 271 list_add_tail(&priv->tx_queue[buf_id].list, &priv->tx_head); 272 273 can_put_echo_skb(skb, dev, buf_id, 0); 274 275 /* Enable interrupt. */ 276 priv->tx_active |= 1 << buf_id; 277 out_8(®s->cantier, priv->tx_active); 278 279 return NETDEV_TX_OK; 280 } 281 282 static enum can_state get_new_state(struct net_device *dev, u8 canrflg) 283 { 284 struct mscan_priv *priv = netdev_priv(dev); 285 286 if (unlikely(canrflg & MSCAN_CSCIF)) 287 return state_map[max(MSCAN_STATE_RX(canrflg), 288 MSCAN_STATE_TX(canrflg))]; 289 290 return priv->can.state; 291 } 292 293 static void mscan_get_rx_frame(struct net_device *dev, struct can_frame *frame) 294 { 295 struct mscan_priv *priv = netdev_priv(dev); 296 struct mscan_regs __iomem *regs = priv->reg_base; 297 u32 can_id; 298 int i; 299 300 can_id = in_be16(®s->rx.idr1_0); 301 if (can_id & (1 << 3)) { 302 frame->can_id = CAN_EFF_FLAG; 303 can_id = ((can_id << 16) | in_be16(®s->rx.idr3_2)); 304 can_id = ((can_id & 0xffe00000) | 305 ((can_id & 0x7ffff) << 2)) >> 2; 306 } else { 307 can_id >>= 4; 308 frame->can_id = 0; 309 } 310 311 frame->can_id |= can_id >> 1; 312 if (can_id & 1) 313 frame->can_id |= CAN_RTR_FLAG; 314 315 frame->len = can_cc_dlc2len(in_8(®s->rx.dlr) & 0xf); 316 317 if (!(frame->can_id & CAN_RTR_FLAG)) { 318 void __iomem *data = ®s->rx.dsr1_0; 319 u16 *payload = (u16 *)frame->data; 320 321 for (i = 0; i < frame->len / 2; i++) { 322 *payload++ = in_be16(data); 323 data += 2 + _MSCAN_RESERVED_DSR_SIZE; 324 } 325 /* read remaining byte if necessary */ 326 if (frame->len & 1) 327 frame->data[frame->len - 1] = in_8(data); 328 } 329 330 out_8(®s->canrflg, MSCAN_RXF); 331 } 332 333 static void mscan_get_err_frame(struct net_device *dev, struct can_frame *frame, 334 u8 canrflg) 335 { 336 struct mscan_priv *priv = netdev_priv(dev); 337 struct mscan_regs __iomem *regs = priv->reg_base; 338 struct net_device_stats *stats = &dev->stats; 339 enum can_state new_state; 340 341 netdev_dbg(dev, "error interrupt (canrflg=%#x)\n", canrflg); 342 frame->can_id = CAN_ERR_FLAG; 343 344 if (canrflg & MSCAN_OVRIF) { 345 frame->can_id |= CAN_ERR_CRTL; 346 frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 347 stats->rx_over_errors++; 348 stats->rx_errors++; 349 } else { 350 frame->data[1] = 0; 351 } 352 353 new_state = get_new_state(dev, canrflg); 354 if (new_state != priv->can.state) { 355 can_change_state(dev, frame, 356 state_map[MSCAN_STATE_TX(canrflg)], 357 state_map[MSCAN_STATE_RX(canrflg)]); 358 359 if (priv->can.state == CAN_STATE_BUS_OFF) { 360 /* 361 * The MSCAN on the MPC5200 does recover from bus-off 362 * automatically. To avoid that we stop the chip doing 363 * a light-weight stop (we are in irq-context). 364 */ 365 if (priv->type != MSCAN_TYPE_MPC5121) { 366 out_8(®s->cantier, 0); 367 out_8(®s->canrier, 0); 368 setbits8(®s->canctl0, 369 MSCAN_SLPRQ | MSCAN_INITRQ); 370 } 371 can_bus_off(dev); 372 } 373 } 374 priv->shadow_statflg = canrflg & MSCAN_STAT_MSK; 375 frame->len = CAN_ERR_DLC; 376 out_8(®s->canrflg, MSCAN_ERR_IF); 377 } 378 379 static int mscan_rx_poll(struct napi_struct *napi, int quota) 380 { 381 struct mscan_priv *priv = container_of(napi, struct mscan_priv, napi); 382 struct net_device *dev = napi->dev; 383 struct mscan_regs __iomem *regs = priv->reg_base; 384 struct net_device_stats *stats = &dev->stats; 385 int work_done = 0; 386 struct sk_buff *skb; 387 struct can_frame *frame; 388 u8 canrflg; 389 390 while (work_done < quota) { 391 canrflg = in_8(®s->canrflg); 392 if (!(canrflg & (MSCAN_RXF | MSCAN_ERR_IF))) 393 break; 394 395 skb = alloc_can_skb(dev, &frame); 396 if (!skb) { 397 if (printk_ratelimit()) 398 netdev_notice(dev, "packet dropped\n"); 399 stats->rx_dropped++; 400 out_8(®s->canrflg, canrflg); 401 continue; 402 } 403 404 if (canrflg & MSCAN_RXF) 405 mscan_get_rx_frame(dev, frame); 406 else if (canrflg & MSCAN_ERR_IF) 407 mscan_get_err_frame(dev, frame, canrflg); 408 409 stats->rx_packets++; 410 stats->rx_bytes += frame->len; 411 work_done++; 412 netif_receive_skb(skb); 413 } 414 415 if (work_done < quota) { 416 if (likely(napi_complete_done(&priv->napi, work_done))) { 417 clear_bit(F_RX_PROGRESS, &priv->flags); 418 if (priv->can.state < CAN_STATE_BUS_OFF) 419 out_8(®s->canrier, priv->shadow_canrier); 420 } 421 } 422 return work_done; 423 } 424 425 static irqreturn_t mscan_isr(int irq, void *dev_id) 426 { 427 struct net_device *dev = (struct net_device *)dev_id; 428 struct mscan_priv *priv = netdev_priv(dev); 429 struct mscan_regs __iomem *regs = priv->reg_base; 430 struct net_device_stats *stats = &dev->stats; 431 u8 cantier, cantflg, canrflg; 432 irqreturn_t ret = IRQ_NONE; 433 434 cantier = in_8(®s->cantier) & MSCAN_TXE; 435 cantflg = in_8(®s->cantflg) & cantier; 436 437 if (cantier && cantflg) { 438 struct list_head *tmp, *pos; 439 440 list_for_each_safe(pos, tmp, &priv->tx_head) { 441 struct tx_queue_entry *entry = 442 list_entry(pos, struct tx_queue_entry, list); 443 u8 mask = entry->mask; 444 445 if (!(cantflg & mask)) 446 continue; 447 448 out_8(®s->cantbsel, mask); 449 stats->tx_bytes += in_8(®s->tx.dlr); 450 stats->tx_packets++; 451 can_get_echo_skb(dev, entry->id, NULL); 452 priv->tx_active &= ~mask; 453 list_del(pos); 454 } 455 456 if (list_empty(&priv->tx_head)) { 457 clear_bit(F_TX_WAIT_ALL, &priv->flags); 458 clear_bit(F_TX_PROGRESS, &priv->flags); 459 priv->cur_pri = 0; 460 } else { 461 netif_trans_update(dev); 462 } 463 464 if (!test_bit(F_TX_WAIT_ALL, &priv->flags)) 465 netif_wake_queue(dev); 466 467 out_8(®s->cantier, priv->tx_active); 468 ret = IRQ_HANDLED; 469 } 470 471 canrflg = in_8(®s->canrflg); 472 if ((canrflg & ~MSCAN_STAT_MSK) && 473 !test_and_set_bit(F_RX_PROGRESS, &priv->flags)) { 474 if (canrflg & ~MSCAN_STAT_MSK) { 475 priv->shadow_canrier = in_8(®s->canrier); 476 out_8(®s->canrier, 0); 477 napi_schedule(&priv->napi); 478 ret = IRQ_HANDLED; 479 } else { 480 clear_bit(F_RX_PROGRESS, &priv->flags); 481 } 482 } 483 return ret; 484 } 485 486 static int mscan_do_set_mode(struct net_device *dev, enum can_mode mode) 487 { 488 int ret = 0; 489 490 switch (mode) { 491 case CAN_MODE_START: 492 ret = mscan_restart(dev); 493 if (ret) 494 break; 495 if (netif_queue_stopped(dev)) 496 netif_wake_queue(dev); 497 break; 498 499 default: 500 ret = -EOPNOTSUPP; 501 break; 502 } 503 return ret; 504 } 505 506 static int mscan_do_set_bittiming(struct net_device *dev) 507 { 508 struct mscan_priv *priv = netdev_priv(dev); 509 struct mscan_regs __iomem *regs = priv->reg_base; 510 struct can_bittiming *bt = &priv->can.bittiming; 511 u8 btr0, btr1; 512 513 btr0 = BTR0_SET_BRP(bt->brp) | BTR0_SET_SJW(bt->sjw); 514 btr1 = (BTR1_SET_TSEG1(bt->prop_seg + bt->phase_seg1) | 515 BTR1_SET_TSEG2(bt->phase_seg2) | 516 BTR1_SET_SAM(priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)); 517 518 netdev_info(dev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1); 519 520 out_8(®s->canbtr0, btr0); 521 out_8(®s->canbtr1, btr1); 522 523 return 0; 524 } 525 526 static int mscan_get_berr_counter(const struct net_device *dev, 527 struct can_berr_counter *bec) 528 { 529 struct mscan_priv *priv = netdev_priv(dev); 530 struct mscan_regs __iomem *regs = priv->reg_base; 531 532 bec->txerr = in_8(®s->cantxerr); 533 bec->rxerr = in_8(®s->canrxerr); 534 535 return 0; 536 } 537 538 static int mscan_open(struct net_device *dev) 539 { 540 int ret; 541 struct mscan_priv *priv = netdev_priv(dev); 542 struct mscan_regs __iomem *regs = priv->reg_base; 543 544 ret = clk_prepare_enable(priv->clk_ipg); 545 if (ret) 546 goto exit_retcode; 547 ret = clk_prepare_enable(priv->clk_can); 548 if (ret) 549 goto exit_dis_ipg_clock; 550 551 /* common open */ 552 ret = open_candev(dev); 553 if (ret) 554 goto exit_dis_can_clock; 555 556 napi_enable(&priv->napi); 557 558 ret = request_irq(dev->irq, mscan_isr, 0, dev->name, dev); 559 if (ret < 0) { 560 netdev_err(dev, "failed to attach interrupt\n"); 561 goto exit_napi_disable; 562 } 563 564 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) 565 setbits8(®s->canctl1, MSCAN_LISTEN); 566 else 567 clrbits8(®s->canctl1, MSCAN_LISTEN); 568 569 ret = mscan_start(dev); 570 if (ret) 571 goto exit_free_irq; 572 573 netif_start_queue(dev); 574 575 return 0; 576 577 exit_free_irq: 578 free_irq(dev->irq, dev); 579 exit_napi_disable: 580 napi_disable(&priv->napi); 581 close_candev(dev); 582 exit_dis_can_clock: 583 clk_disable_unprepare(priv->clk_can); 584 exit_dis_ipg_clock: 585 clk_disable_unprepare(priv->clk_ipg); 586 exit_retcode: 587 return ret; 588 } 589 590 static int mscan_close(struct net_device *dev) 591 { 592 struct mscan_priv *priv = netdev_priv(dev); 593 struct mscan_regs __iomem *regs = priv->reg_base; 594 595 netif_stop_queue(dev); 596 napi_disable(&priv->napi); 597 598 out_8(®s->cantier, 0); 599 out_8(®s->canrier, 0); 600 mscan_set_mode(dev, MSCAN_INIT_MODE); 601 close_candev(dev); 602 free_irq(dev->irq, dev); 603 604 clk_disable_unprepare(priv->clk_can); 605 clk_disable_unprepare(priv->clk_ipg); 606 607 return 0; 608 } 609 610 static const struct net_device_ops mscan_netdev_ops = { 611 .ndo_open = mscan_open, 612 .ndo_stop = mscan_close, 613 .ndo_start_xmit = mscan_start_xmit, 614 .ndo_change_mtu = can_change_mtu, 615 }; 616 617 int register_mscandev(struct net_device *dev, int mscan_clksrc) 618 { 619 struct mscan_priv *priv = netdev_priv(dev); 620 struct mscan_regs __iomem *regs = priv->reg_base; 621 u8 ctl1; 622 623 ctl1 = in_8(®s->canctl1); 624 if (mscan_clksrc) 625 ctl1 |= MSCAN_CLKSRC; 626 else 627 ctl1 &= ~MSCAN_CLKSRC; 628 629 if (priv->type == MSCAN_TYPE_MPC5121) { 630 priv->can.do_get_berr_counter = mscan_get_berr_counter; 631 ctl1 |= MSCAN_BORM; /* bus-off recovery upon request */ 632 } 633 634 ctl1 |= MSCAN_CANE; 635 out_8(®s->canctl1, ctl1); 636 udelay(100); 637 638 /* acceptance mask/acceptance code (accept everything) */ 639 out_be16(®s->canidar1_0, 0); 640 out_be16(®s->canidar3_2, 0); 641 out_be16(®s->canidar5_4, 0); 642 out_be16(®s->canidar7_6, 0); 643 644 out_be16(®s->canidmr1_0, 0xffff); 645 out_be16(®s->canidmr3_2, 0xffff); 646 out_be16(®s->canidmr5_4, 0xffff); 647 out_be16(®s->canidmr7_6, 0xffff); 648 /* Two 32 bit Acceptance Filters */ 649 out_8(®s->canidac, MSCAN_AF_32BIT); 650 651 mscan_set_mode(dev, MSCAN_INIT_MODE); 652 653 return register_candev(dev); 654 } 655 656 void unregister_mscandev(struct net_device *dev) 657 { 658 struct mscan_priv *priv = netdev_priv(dev); 659 struct mscan_regs __iomem *regs = priv->reg_base; 660 mscan_set_mode(dev, MSCAN_INIT_MODE); 661 clrbits8(®s->canctl1, MSCAN_CANE); 662 unregister_candev(dev); 663 } 664 665 struct net_device *alloc_mscandev(void) 666 { 667 struct net_device *dev; 668 struct mscan_priv *priv; 669 int i; 670 671 dev = alloc_candev(sizeof(struct mscan_priv), MSCAN_ECHO_SKB_MAX); 672 if (!dev) 673 return NULL; 674 priv = netdev_priv(dev); 675 676 dev->netdev_ops = &mscan_netdev_ops; 677 678 dev->flags |= IFF_ECHO; /* we support local echo */ 679 680 netif_napi_add(dev, &priv->napi, mscan_rx_poll, 8); 681 682 priv->can.bittiming_const = &mscan_bittiming_const; 683 priv->can.do_set_bittiming = mscan_do_set_bittiming; 684 priv->can.do_set_mode = mscan_do_set_mode; 685 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES | 686 CAN_CTRLMODE_LISTENONLY; 687 688 for (i = 0; i < TX_QUEUE_SIZE; i++) { 689 priv->tx_queue[i].id = i; 690 priv->tx_queue[i].mask = 1 << i; 691 } 692 693 return dev; 694 } 695 696 MODULE_AUTHOR("Andrey Volkov <avolkov@varma-el.com>"); 697 MODULE_LICENSE("GPL v2"); 698 MODULE_DESCRIPTION("CAN port driver for a MSCAN based chips"); 699