1 // SPDX-License-Identifier: GPL-2.0-only 2 /* SocketCAN driver for Microchip CAN BUS Analyzer Tool 3 * 4 * Copyright (C) 2017 Mobica Limited 5 * 6 * This driver is inspired by the 4.6.2 version of net/can/usb/usb_8dev.c 7 */ 8 9 #include <asm/unaligned.h> 10 #include <linux/can.h> 11 #include <linux/can/dev.h> 12 #include <linux/can/error.h> 13 #include <linux/ethtool.h> 14 #include <linux/module.h> 15 #include <linux/netdevice.h> 16 #include <linux/signal.h> 17 #include <linux/slab.h> 18 #include <linux/usb.h> 19 20 /* vendor and product id */ 21 #define MCBA_MODULE_NAME "mcba_usb" 22 #define MCBA_VENDOR_ID 0x04d8 23 #define MCBA_PRODUCT_ID 0x0a30 24 25 /* driver constants */ 26 #define MCBA_MAX_RX_URBS 20 27 #define MCBA_MAX_TX_URBS 20 28 #define MCBA_CTX_FREE MCBA_MAX_TX_URBS 29 30 /* RX buffer must be bigger than msg size since at the 31 * beginning USB messages are stacked. 32 */ 33 #define MCBA_USB_RX_BUFF_SIZE 64 34 #define MCBA_USB_TX_BUFF_SIZE (sizeof(struct mcba_usb_msg)) 35 36 /* Microchip command id */ 37 #define MBCA_CMD_RECEIVE_MESSAGE 0xE3 38 #define MBCA_CMD_I_AM_ALIVE_FROM_CAN 0xF5 39 #define MBCA_CMD_I_AM_ALIVE_FROM_USB 0xF7 40 #define MBCA_CMD_CHANGE_BIT_RATE 0xA1 41 #define MBCA_CMD_TRANSMIT_MESSAGE_EV 0xA3 42 #define MBCA_CMD_SETUP_TERMINATION_RESISTANCE 0xA8 43 #define MBCA_CMD_READ_FW_VERSION 0xA9 44 #define MBCA_CMD_NOTHING_TO_SEND 0xFF 45 #define MBCA_CMD_TRANSMIT_MESSAGE_RSP 0xE2 46 47 #define MCBA_VER_REQ_USB 1 48 #define MCBA_VER_REQ_CAN 2 49 50 #define MCBA_SIDL_EXID_MASK 0x8 51 #define MCBA_DLC_MASK 0xf 52 #define MCBA_DLC_RTR_MASK 0x40 53 54 #define MCBA_CAN_STATE_WRN_TH 95 55 #define MCBA_CAN_STATE_ERR_PSV_TH 127 56 57 #define MCBA_TERMINATION_DISABLED CAN_TERMINATION_DISABLED 58 #define MCBA_TERMINATION_ENABLED 120 59 60 struct mcba_usb_ctx { 61 struct mcba_priv *priv; 62 u32 ndx; 63 bool can; 64 }; 65 66 /* Structure to hold all of our device specific stuff */ 67 struct mcba_priv { 68 struct can_priv can; /* must be the first member */ 69 struct sk_buff *echo_skb[MCBA_MAX_TX_URBS]; 70 struct mcba_usb_ctx tx_context[MCBA_MAX_TX_URBS]; 71 struct usb_device *udev; 72 struct net_device *netdev; 73 struct usb_anchor tx_submitted; 74 struct usb_anchor rx_submitted; 75 struct can_berr_counter bec; 76 bool usb_ka_first_pass; 77 bool can_ka_first_pass; 78 bool can_speed_check; 79 atomic_t free_ctx_cnt; 80 void *rxbuf[MCBA_MAX_RX_URBS]; 81 dma_addr_t rxbuf_dma[MCBA_MAX_RX_URBS]; 82 int rx_pipe; 83 int tx_pipe; 84 }; 85 86 /* CAN frame */ 87 struct __packed mcba_usb_msg_can { 88 u8 cmd_id; 89 __be16 eid; 90 __be16 sid; 91 u8 dlc; 92 u8 data[8]; 93 u8 timestamp[4]; 94 u8 checksum; 95 }; 96 97 /* command frame */ 98 struct __packed mcba_usb_msg { 99 u8 cmd_id; 100 u8 unused[18]; 101 }; 102 103 struct __packed mcba_usb_msg_ka_usb { 104 u8 cmd_id; 105 u8 termination_state; 106 u8 soft_ver_major; 107 u8 soft_ver_minor; 108 u8 unused[15]; 109 }; 110 111 struct __packed mcba_usb_msg_ka_can { 112 u8 cmd_id; 113 u8 tx_err_cnt; 114 u8 rx_err_cnt; 115 u8 rx_buff_ovfl; 116 u8 tx_bus_off; 117 __be16 can_bitrate; 118 __le16 rx_lost; 119 u8 can_stat; 120 u8 soft_ver_major; 121 u8 soft_ver_minor; 122 u8 debug_mode; 123 u8 test_complete; 124 u8 test_result; 125 u8 unused[4]; 126 }; 127 128 struct __packed mcba_usb_msg_change_bitrate { 129 u8 cmd_id; 130 __be16 bitrate; 131 u8 unused[16]; 132 }; 133 134 struct __packed mcba_usb_msg_termination { 135 u8 cmd_id; 136 u8 termination; 137 u8 unused[17]; 138 }; 139 140 struct __packed mcba_usb_msg_fw_ver { 141 u8 cmd_id; 142 u8 pic; 143 u8 unused[17]; 144 }; 145 146 static const struct usb_device_id mcba_usb_table[] = { 147 { USB_DEVICE(MCBA_VENDOR_ID, MCBA_PRODUCT_ID) }, 148 {} /* Terminating entry */ 149 }; 150 151 MODULE_DEVICE_TABLE(usb, mcba_usb_table); 152 153 static const u16 mcba_termination[] = { MCBA_TERMINATION_DISABLED, 154 MCBA_TERMINATION_ENABLED }; 155 156 static const u32 mcba_bitrate[] = { 20000, 33333, 50000, 80000, 83333, 157 100000, 125000, 150000, 175000, 200000, 158 225000, 250000, 275000, 300000, 500000, 159 625000, 800000, 1000000 }; 160 161 static inline void mcba_init_ctx(struct mcba_priv *priv) 162 { 163 int i = 0; 164 165 for (i = 0; i < MCBA_MAX_TX_URBS; i++) { 166 priv->tx_context[i].ndx = MCBA_CTX_FREE; 167 priv->tx_context[i].priv = priv; 168 } 169 170 atomic_set(&priv->free_ctx_cnt, ARRAY_SIZE(priv->tx_context)); 171 } 172 173 static inline struct mcba_usb_ctx *mcba_usb_get_free_ctx(struct mcba_priv *priv, 174 struct can_frame *cf) 175 { 176 int i = 0; 177 struct mcba_usb_ctx *ctx = NULL; 178 179 for (i = 0; i < MCBA_MAX_TX_URBS; i++) { 180 if (priv->tx_context[i].ndx == MCBA_CTX_FREE) { 181 ctx = &priv->tx_context[i]; 182 ctx->ndx = i; 183 184 if (cf) 185 ctx->can = true; 186 else 187 ctx->can = false; 188 189 atomic_dec(&priv->free_ctx_cnt); 190 break; 191 } 192 } 193 194 if (!atomic_read(&priv->free_ctx_cnt)) 195 /* That was the last free ctx. Slow down tx path */ 196 netif_stop_queue(priv->netdev); 197 198 return ctx; 199 } 200 201 /* mcba_usb_free_ctx and mcba_usb_get_free_ctx are executed by different 202 * threads. The order of execution in below function is important. 203 */ 204 static inline void mcba_usb_free_ctx(struct mcba_usb_ctx *ctx) 205 { 206 /* Increase number of free ctxs before freeing ctx */ 207 atomic_inc(&ctx->priv->free_ctx_cnt); 208 209 ctx->ndx = MCBA_CTX_FREE; 210 211 /* Wake up the queue once ctx is marked free */ 212 netif_wake_queue(ctx->priv->netdev); 213 } 214 215 static void mcba_usb_write_bulk_callback(struct urb *urb) 216 { 217 struct mcba_usb_ctx *ctx = urb->context; 218 struct net_device *netdev; 219 220 WARN_ON(!ctx); 221 222 netdev = ctx->priv->netdev; 223 224 /* free up our allocated buffer */ 225 usb_free_coherent(urb->dev, urb->transfer_buffer_length, 226 urb->transfer_buffer, urb->transfer_dma); 227 228 if (ctx->can) { 229 if (!netif_device_present(netdev)) 230 return; 231 232 netdev->stats.tx_packets++; 233 netdev->stats.tx_bytes += can_get_echo_skb(netdev, ctx->ndx, 234 NULL); 235 } 236 237 if (urb->status) 238 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status); 239 240 /* Release the context */ 241 mcba_usb_free_ctx(ctx); 242 } 243 244 /* Send data to device */ 245 static netdev_tx_t mcba_usb_xmit(struct mcba_priv *priv, 246 struct mcba_usb_msg *usb_msg, 247 struct mcba_usb_ctx *ctx) 248 { 249 struct urb *urb; 250 u8 *buf; 251 int err; 252 253 /* create a URB, and a buffer for it, and copy the data to the URB */ 254 urb = usb_alloc_urb(0, GFP_ATOMIC); 255 if (!urb) 256 return -ENOMEM; 257 258 buf = usb_alloc_coherent(priv->udev, MCBA_USB_TX_BUFF_SIZE, GFP_ATOMIC, 259 &urb->transfer_dma); 260 if (!buf) { 261 err = -ENOMEM; 262 goto nomembuf; 263 } 264 265 memcpy(buf, usb_msg, MCBA_USB_TX_BUFF_SIZE); 266 267 usb_fill_bulk_urb(urb, priv->udev, priv->tx_pipe, buf, MCBA_USB_TX_BUFF_SIZE, 268 mcba_usb_write_bulk_callback, ctx); 269 270 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 271 usb_anchor_urb(urb, &priv->tx_submitted); 272 273 err = usb_submit_urb(urb, GFP_ATOMIC); 274 if (unlikely(err)) 275 goto failed; 276 277 /* Release our reference to this URB, the USB core will eventually free 278 * it entirely. 279 */ 280 usb_free_urb(urb); 281 282 return 0; 283 284 failed: 285 usb_unanchor_urb(urb); 286 usb_free_coherent(priv->udev, MCBA_USB_TX_BUFF_SIZE, buf, 287 urb->transfer_dma); 288 289 if (err == -ENODEV) 290 netif_device_detach(priv->netdev); 291 else 292 netdev_warn(priv->netdev, "failed tx_urb %d\n", err); 293 294 nomembuf: 295 usb_free_urb(urb); 296 297 return err; 298 } 299 300 /* Send data to device */ 301 static netdev_tx_t mcba_usb_start_xmit(struct sk_buff *skb, 302 struct net_device *netdev) 303 { 304 struct mcba_priv *priv = netdev_priv(netdev); 305 struct can_frame *cf = (struct can_frame *)skb->data; 306 struct mcba_usb_ctx *ctx = NULL; 307 struct net_device_stats *stats = &priv->netdev->stats; 308 u16 sid; 309 int err; 310 struct mcba_usb_msg_can usb_msg = { 311 .cmd_id = MBCA_CMD_TRANSMIT_MESSAGE_EV 312 }; 313 314 if (can_dropped_invalid_skb(netdev, skb)) 315 return NETDEV_TX_OK; 316 317 ctx = mcba_usb_get_free_ctx(priv, cf); 318 if (!ctx) 319 return NETDEV_TX_BUSY; 320 321 if (cf->can_id & CAN_EFF_FLAG) { 322 /* SIDH | SIDL | EIDH | EIDL 323 * 28 - 21 | 20 19 18 x x x 17 16 | 15 - 8 | 7 - 0 324 */ 325 sid = MCBA_SIDL_EXID_MASK; 326 /* store 28-18 bits */ 327 sid |= (cf->can_id & 0x1ffc0000) >> 13; 328 /* store 17-16 bits */ 329 sid |= (cf->can_id & 0x30000) >> 16; 330 put_unaligned_be16(sid, &usb_msg.sid); 331 332 /* store 15-0 bits */ 333 put_unaligned_be16(cf->can_id & 0xffff, &usb_msg.eid); 334 } else { 335 /* SIDH | SIDL 336 * 10 - 3 | 2 1 0 x x x x x 337 */ 338 put_unaligned_be16((cf->can_id & CAN_SFF_MASK) << 5, 339 &usb_msg.sid); 340 usb_msg.eid = 0; 341 } 342 343 usb_msg.dlc = cf->len; 344 345 memcpy(usb_msg.data, cf->data, usb_msg.dlc); 346 347 if (cf->can_id & CAN_RTR_FLAG) 348 usb_msg.dlc |= MCBA_DLC_RTR_MASK; 349 350 can_put_echo_skb(skb, priv->netdev, ctx->ndx, 0); 351 352 err = mcba_usb_xmit(priv, (struct mcba_usb_msg *)&usb_msg, ctx); 353 if (err) 354 goto xmit_failed; 355 356 return NETDEV_TX_OK; 357 358 xmit_failed: 359 can_free_echo_skb(priv->netdev, ctx->ndx, NULL); 360 mcba_usb_free_ctx(ctx); 361 stats->tx_dropped++; 362 363 return NETDEV_TX_OK; 364 } 365 366 /* Send cmd to device */ 367 static void mcba_usb_xmit_cmd(struct mcba_priv *priv, 368 struct mcba_usb_msg *usb_msg) 369 { 370 struct mcba_usb_ctx *ctx = NULL; 371 int err; 372 373 ctx = mcba_usb_get_free_ctx(priv, NULL); 374 if (!ctx) { 375 netdev_err(priv->netdev, 376 "Lack of free ctx. Sending (%d) cmd aborted", 377 usb_msg->cmd_id); 378 379 return; 380 } 381 382 err = mcba_usb_xmit(priv, usb_msg, ctx); 383 if (err) 384 netdev_err(priv->netdev, "Failed to send cmd (%d)", 385 usb_msg->cmd_id); 386 } 387 388 static void mcba_usb_xmit_change_bitrate(struct mcba_priv *priv, u16 bitrate) 389 { 390 struct mcba_usb_msg_change_bitrate usb_msg = { 391 .cmd_id = MBCA_CMD_CHANGE_BIT_RATE 392 }; 393 394 put_unaligned_be16(bitrate, &usb_msg.bitrate); 395 396 mcba_usb_xmit_cmd(priv, (struct mcba_usb_msg *)&usb_msg); 397 } 398 399 static void mcba_usb_xmit_read_fw_ver(struct mcba_priv *priv, u8 pic) 400 { 401 struct mcba_usb_msg_fw_ver usb_msg = { 402 .cmd_id = MBCA_CMD_READ_FW_VERSION, 403 .pic = pic 404 }; 405 406 mcba_usb_xmit_cmd(priv, (struct mcba_usb_msg *)&usb_msg); 407 } 408 409 static void mcba_usb_process_can(struct mcba_priv *priv, 410 struct mcba_usb_msg_can *msg) 411 { 412 struct can_frame *cf; 413 struct sk_buff *skb; 414 struct net_device_stats *stats = &priv->netdev->stats; 415 u16 sid; 416 417 skb = alloc_can_skb(priv->netdev, &cf); 418 if (!skb) 419 return; 420 421 sid = get_unaligned_be16(&msg->sid); 422 423 if (sid & MCBA_SIDL_EXID_MASK) { 424 /* SIDH | SIDL | EIDH | EIDL 425 * 28 - 21 | 20 19 18 x x x 17 16 | 15 - 8 | 7 - 0 426 */ 427 cf->can_id = CAN_EFF_FLAG; 428 429 /* store 28-18 bits */ 430 cf->can_id |= (sid & 0xffe0) << 13; 431 /* store 17-16 bits */ 432 cf->can_id |= (sid & 3) << 16; 433 /* store 15-0 bits */ 434 cf->can_id |= get_unaligned_be16(&msg->eid); 435 } else { 436 /* SIDH | SIDL 437 * 10 - 3 | 2 1 0 x x x x x 438 */ 439 cf->can_id = (sid & 0xffe0) >> 5; 440 } 441 442 cf->len = can_cc_dlc2len(msg->dlc & MCBA_DLC_MASK); 443 444 if (msg->dlc & MCBA_DLC_RTR_MASK) { 445 cf->can_id |= CAN_RTR_FLAG; 446 } else { 447 memcpy(cf->data, msg->data, cf->len); 448 449 stats->rx_bytes += cf->len; 450 } 451 stats->rx_packets++; 452 453 netif_rx(skb); 454 } 455 456 static void mcba_usb_process_ka_usb(struct mcba_priv *priv, 457 struct mcba_usb_msg_ka_usb *msg) 458 { 459 if (unlikely(priv->usb_ka_first_pass)) { 460 netdev_info(priv->netdev, "PIC USB version %u.%u\n", 461 msg->soft_ver_major, msg->soft_ver_minor); 462 463 priv->usb_ka_first_pass = false; 464 } 465 466 if (msg->termination_state) 467 priv->can.termination = MCBA_TERMINATION_ENABLED; 468 else 469 priv->can.termination = MCBA_TERMINATION_DISABLED; 470 } 471 472 static u32 convert_can2host_bitrate(struct mcba_usb_msg_ka_can *msg) 473 { 474 const u32 bitrate = get_unaligned_be16(&msg->can_bitrate); 475 476 if ((bitrate == 33) || (bitrate == 83)) 477 return bitrate * 1000 + 333; 478 else 479 return bitrate * 1000; 480 } 481 482 static void mcba_usb_process_ka_can(struct mcba_priv *priv, 483 struct mcba_usb_msg_ka_can *msg) 484 { 485 if (unlikely(priv->can_ka_first_pass)) { 486 netdev_info(priv->netdev, "PIC CAN version %u.%u\n", 487 msg->soft_ver_major, msg->soft_ver_minor); 488 489 priv->can_ka_first_pass = false; 490 } 491 492 if (unlikely(priv->can_speed_check)) { 493 const u32 bitrate = convert_can2host_bitrate(msg); 494 495 priv->can_speed_check = false; 496 497 if (bitrate != priv->can.bittiming.bitrate) 498 netdev_err( 499 priv->netdev, 500 "Wrong bitrate reported by the device (%u). Expected %u", 501 bitrate, priv->can.bittiming.bitrate); 502 } 503 504 priv->bec.txerr = msg->tx_err_cnt; 505 priv->bec.rxerr = msg->rx_err_cnt; 506 507 if (msg->tx_bus_off) 508 priv->can.state = CAN_STATE_BUS_OFF; 509 510 else if ((priv->bec.txerr > MCBA_CAN_STATE_ERR_PSV_TH) || 511 (priv->bec.rxerr > MCBA_CAN_STATE_ERR_PSV_TH)) 512 priv->can.state = CAN_STATE_ERROR_PASSIVE; 513 514 else if ((priv->bec.txerr > MCBA_CAN_STATE_WRN_TH) || 515 (priv->bec.rxerr > MCBA_CAN_STATE_WRN_TH)) 516 priv->can.state = CAN_STATE_ERROR_WARNING; 517 } 518 519 static void mcba_usb_process_rx(struct mcba_priv *priv, 520 struct mcba_usb_msg *msg) 521 { 522 switch (msg->cmd_id) { 523 case MBCA_CMD_I_AM_ALIVE_FROM_CAN: 524 mcba_usb_process_ka_can(priv, 525 (struct mcba_usb_msg_ka_can *)msg); 526 break; 527 528 case MBCA_CMD_I_AM_ALIVE_FROM_USB: 529 mcba_usb_process_ka_usb(priv, 530 (struct mcba_usb_msg_ka_usb *)msg); 531 break; 532 533 case MBCA_CMD_RECEIVE_MESSAGE: 534 mcba_usb_process_can(priv, (struct mcba_usb_msg_can *)msg); 535 break; 536 537 case MBCA_CMD_NOTHING_TO_SEND: 538 /* Side effect of communication between PIC_USB and PIC_CAN. 539 * PIC_CAN is telling us that it has nothing to send 540 */ 541 break; 542 543 case MBCA_CMD_TRANSMIT_MESSAGE_RSP: 544 /* Transmission response from the device containing timestamp */ 545 break; 546 547 default: 548 netdev_warn(priv->netdev, "Unsupported msg (0x%X)", 549 msg->cmd_id); 550 break; 551 } 552 } 553 554 /* Callback for reading data from device 555 * 556 * Check urb status, call read function and resubmit urb read operation. 557 */ 558 static void mcba_usb_read_bulk_callback(struct urb *urb) 559 { 560 struct mcba_priv *priv = urb->context; 561 struct net_device *netdev; 562 int retval; 563 int pos = 0; 564 565 netdev = priv->netdev; 566 567 if (!netif_device_present(netdev)) 568 return; 569 570 switch (urb->status) { 571 case 0: /* success */ 572 break; 573 574 case -ENOENT: 575 case -EPIPE: 576 case -EPROTO: 577 case -ESHUTDOWN: 578 return; 579 580 default: 581 netdev_info(netdev, "Rx URB aborted (%d)\n", urb->status); 582 583 goto resubmit_urb; 584 } 585 586 while (pos < urb->actual_length) { 587 struct mcba_usb_msg *msg; 588 589 if (pos + sizeof(struct mcba_usb_msg) > urb->actual_length) { 590 netdev_err(priv->netdev, "format error\n"); 591 break; 592 } 593 594 msg = (struct mcba_usb_msg *)(urb->transfer_buffer + pos); 595 mcba_usb_process_rx(priv, msg); 596 597 pos += sizeof(struct mcba_usb_msg); 598 } 599 600 resubmit_urb: 601 602 usb_fill_bulk_urb(urb, priv->udev, 603 priv->rx_pipe, 604 urb->transfer_buffer, MCBA_USB_RX_BUFF_SIZE, 605 mcba_usb_read_bulk_callback, priv); 606 607 retval = usb_submit_urb(urb, GFP_ATOMIC); 608 609 if (retval == -ENODEV) 610 netif_device_detach(netdev); 611 else if (retval) 612 netdev_err(netdev, "failed resubmitting read bulk urb: %d\n", 613 retval); 614 } 615 616 /* Start USB device */ 617 static int mcba_usb_start(struct mcba_priv *priv) 618 { 619 struct net_device *netdev = priv->netdev; 620 int err, i; 621 622 mcba_init_ctx(priv); 623 624 for (i = 0; i < MCBA_MAX_RX_URBS; i++) { 625 struct urb *urb = NULL; 626 u8 *buf; 627 dma_addr_t buf_dma; 628 629 /* create a URB, and a buffer for it */ 630 urb = usb_alloc_urb(0, GFP_KERNEL); 631 if (!urb) { 632 err = -ENOMEM; 633 break; 634 } 635 636 buf = usb_alloc_coherent(priv->udev, MCBA_USB_RX_BUFF_SIZE, 637 GFP_KERNEL, &buf_dma); 638 if (!buf) { 639 netdev_err(netdev, "No memory left for USB buffer\n"); 640 usb_free_urb(urb); 641 err = -ENOMEM; 642 break; 643 } 644 645 urb->transfer_dma = buf_dma; 646 647 usb_fill_bulk_urb(urb, priv->udev, 648 priv->rx_pipe, 649 buf, MCBA_USB_RX_BUFF_SIZE, 650 mcba_usb_read_bulk_callback, priv); 651 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 652 usb_anchor_urb(urb, &priv->rx_submitted); 653 654 err = usb_submit_urb(urb, GFP_KERNEL); 655 if (err) { 656 usb_unanchor_urb(urb); 657 usb_free_coherent(priv->udev, MCBA_USB_RX_BUFF_SIZE, 658 buf, buf_dma); 659 usb_free_urb(urb); 660 break; 661 } 662 663 priv->rxbuf[i] = buf; 664 priv->rxbuf_dma[i] = buf_dma; 665 666 /* Drop reference, USB core will take care of freeing it */ 667 usb_free_urb(urb); 668 } 669 670 /* Did we submit any URBs */ 671 if (i == 0) { 672 netdev_warn(netdev, "couldn't setup read URBs\n"); 673 return err; 674 } 675 676 /* Warn if we've couldn't transmit all the URBs */ 677 if (i < MCBA_MAX_RX_URBS) 678 netdev_warn(netdev, "rx performance may be slow\n"); 679 680 mcba_usb_xmit_read_fw_ver(priv, MCBA_VER_REQ_USB); 681 mcba_usb_xmit_read_fw_ver(priv, MCBA_VER_REQ_CAN); 682 683 return err; 684 } 685 686 /* Open USB device */ 687 static int mcba_usb_open(struct net_device *netdev) 688 { 689 struct mcba_priv *priv = netdev_priv(netdev); 690 int err; 691 692 /* common open */ 693 err = open_candev(netdev); 694 if (err) 695 return err; 696 697 priv->can_speed_check = true; 698 priv->can.state = CAN_STATE_ERROR_ACTIVE; 699 700 netif_start_queue(netdev); 701 702 return 0; 703 } 704 705 static void mcba_urb_unlink(struct mcba_priv *priv) 706 { 707 int i; 708 709 usb_kill_anchored_urbs(&priv->rx_submitted); 710 711 for (i = 0; i < MCBA_MAX_RX_URBS; ++i) 712 usb_free_coherent(priv->udev, MCBA_USB_RX_BUFF_SIZE, 713 priv->rxbuf[i], priv->rxbuf_dma[i]); 714 715 usb_kill_anchored_urbs(&priv->tx_submitted); 716 } 717 718 /* Close USB device */ 719 static int mcba_usb_close(struct net_device *netdev) 720 { 721 struct mcba_priv *priv = netdev_priv(netdev); 722 723 priv->can.state = CAN_STATE_STOPPED; 724 725 netif_stop_queue(netdev); 726 727 /* Stop polling */ 728 mcba_urb_unlink(priv); 729 730 close_candev(netdev); 731 732 return 0; 733 } 734 735 /* Set network device mode 736 * 737 * Maybe we should leave this function empty, because the device 738 * set mode variable with open command. 739 */ 740 static int mcba_net_set_mode(struct net_device *netdev, enum can_mode mode) 741 { 742 return 0; 743 } 744 745 static int mcba_net_get_berr_counter(const struct net_device *netdev, 746 struct can_berr_counter *bec) 747 { 748 struct mcba_priv *priv = netdev_priv(netdev); 749 750 bec->txerr = priv->bec.txerr; 751 bec->rxerr = priv->bec.rxerr; 752 753 return 0; 754 } 755 756 static const struct net_device_ops mcba_netdev_ops = { 757 .ndo_open = mcba_usb_open, 758 .ndo_stop = mcba_usb_close, 759 .ndo_start_xmit = mcba_usb_start_xmit, 760 }; 761 762 static const struct ethtool_ops mcba_ethtool_ops = { 763 .get_ts_info = ethtool_op_get_ts_info, 764 }; 765 766 /* Microchip CANBUS has hardcoded bittiming values by default. 767 * This function sends request via USB to change the speed and align bittiming 768 * values for presentation purposes only 769 */ 770 static int mcba_net_set_bittiming(struct net_device *netdev) 771 { 772 struct mcba_priv *priv = netdev_priv(netdev); 773 const u16 bitrate_kbps = priv->can.bittiming.bitrate / 1000; 774 775 mcba_usb_xmit_change_bitrate(priv, bitrate_kbps); 776 777 return 0; 778 } 779 780 static int mcba_set_termination(struct net_device *netdev, u16 term) 781 { 782 struct mcba_priv *priv = netdev_priv(netdev); 783 struct mcba_usb_msg_termination usb_msg = { 784 .cmd_id = MBCA_CMD_SETUP_TERMINATION_RESISTANCE 785 }; 786 787 if (term == MCBA_TERMINATION_ENABLED) 788 usb_msg.termination = 1; 789 else 790 usb_msg.termination = 0; 791 792 mcba_usb_xmit_cmd(priv, (struct mcba_usb_msg *)&usb_msg); 793 794 return 0; 795 } 796 797 static int mcba_usb_probe(struct usb_interface *intf, 798 const struct usb_device_id *id) 799 { 800 struct net_device *netdev; 801 struct mcba_priv *priv; 802 int err; 803 struct usb_device *usbdev = interface_to_usbdev(intf); 804 struct usb_endpoint_descriptor *in, *out; 805 806 err = usb_find_common_endpoints(intf->cur_altsetting, &in, &out, NULL, NULL); 807 if (err) { 808 dev_err(&intf->dev, "Can't find endpoints\n"); 809 return err; 810 } 811 812 netdev = alloc_candev(sizeof(struct mcba_priv), MCBA_MAX_TX_URBS); 813 if (!netdev) { 814 dev_err(&intf->dev, "Couldn't alloc candev\n"); 815 return -ENOMEM; 816 } 817 818 priv = netdev_priv(netdev); 819 820 priv->udev = usbdev; 821 priv->netdev = netdev; 822 priv->usb_ka_first_pass = true; 823 priv->can_ka_first_pass = true; 824 priv->can_speed_check = false; 825 826 init_usb_anchor(&priv->rx_submitted); 827 init_usb_anchor(&priv->tx_submitted); 828 829 usb_set_intfdata(intf, priv); 830 831 /* Init CAN device */ 832 priv->can.state = CAN_STATE_STOPPED; 833 priv->can.termination_const = mcba_termination; 834 priv->can.termination_const_cnt = ARRAY_SIZE(mcba_termination); 835 priv->can.bitrate_const = mcba_bitrate; 836 priv->can.bitrate_const_cnt = ARRAY_SIZE(mcba_bitrate); 837 838 priv->can.do_set_termination = mcba_set_termination; 839 priv->can.do_set_mode = mcba_net_set_mode; 840 priv->can.do_get_berr_counter = mcba_net_get_berr_counter; 841 priv->can.do_set_bittiming = mcba_net_set_bittiming; 842 843 netdev->netdev_ops = &mcba_netdev_ops; 844 netdev->ethtool_ops = &mcba_ethtool_ops; 845 846 netdev->flags |= IFF_ECHO; /* we support local echo */ 847 848 SET_NETDEV_DEV(netdev, &intf->dev); 849 850 err = register_candev(netdev); 851 if (err) { 852 netdev_err(netdev, "couldn't register CAN device: %d\n", err); 853 854 goto cleanup_free_candev; 855 } 856 857 priv->rx_pipe = usb_rcvbulkpipe(priv->udev, in->bEndpointAddress); 858 priv->tx_pipe = usb_sndbulkpipe(priv->udev, out->bEndpointAddress); 859 860 /* Start USB dev only if we have successfully registered CAN device */ 861 err = mcba_usb_start(priv); 862 if (err) { 863 if (err == -ENODEV) 864 netif_device_detach(priv->netdev); 865 866 netdev_warn(netdev, "couldn't start device: %d\n", err); 867 868 goto cleanup_unregister_candev; 869 } 870 871 dev_info(&intf->dev, "Microchip CAN BUS Analyzer connected\n"); 872 873 return 0; 874 875 cleanup_unregister_candev: 876 unregister_candev(priv->netdev); 877 878 cleanup_free_candev: 879 free_candev(netdev); 880 881 return err; 882 } 883 884 /* Called by the usb core when driver is unloaded or device is removed */ 885 static void mcba_usb_disconnect(struct usb_interface *intf) 886 { 887 struct mcba_priv *priv = usb_get_intfdata(intf); 888 889 usb_set_intfdata(intf, NULL); 890 891 netdev_info(priv->netdev, "device disconnected\n"); 892 893 unregister_candev(priv->netdev); 894 mcba_urb_unlink(priv); 895 free_candev(priv->netdev); 896 } 897 898 static struct usb_driver mcba_usb_driver = { 899 .name = MCBA_MODULE_NAME, 900 .probe = mcba_usb_probe, 901 .disconnect = mcba_usb_disconnect, 902 .id_table = mcba_usb_table, 903 }; 904 905 module_usb_driver(mcba_usb_driver); 906 907 MODULE_AUTHOR("Remigiusz Kołłątaj <remigiusz.kollataj@mobica.com>"); 908 MODULE_DESCRIPTION("SocketCAN driver for Microchip CAN BUS Analyzer Tool"); 909 MODULE_LICENSE("GPL v2"); 910