1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * CAN driver for "8 devices" USB2CAN converter 4 * 5 * Copyright (C) 2012 Bernd Krumboeck (krumboeck@universalnet.at) 6 * 7 * This driver is inspired by the 3.2.0 version of drivers/net/can/usb/ems_usb.c 8 * and drivers/net/can/usb/esd_usb2.c 9 * 10 * Many thanks to Gerhard Bertelsmann (info@gerhard-bertelsmann.de) 11 * for testing and fixing this driver. Also many thanks to "8 devices", 12 * who were very cooperative and answered my questions. 13 */ 14 15 #include <linux/signal.h> 16 #include <linux/slab.h> 17 #include <linux/module.h> 18 #include <linux/netdevice.h> 19 #include <linux/usb.h> 20 21 #include <linux/can.h> 22 #include <linux/can/dev.h> 23 #include <linux/can/error.h> 24 #include <linux/can/led.h> 25 26 /* driver constants */ 27 #define MAX_RX_URBS 20 28 #define MAX_TX_URBS 20 29 #define RX_BUFFER_SIZE 64 30 31 /* vendor and product id */ 32 #define USB_8DEV_VENDOR_ID 0x0483 33 #define USB_8DEV_PRODUCT_ID 0x1234 34 35 /* endpoints */ 36 enum usb_8dev_endpoint { 37 USB_8DEV_ENDP_DATA_RX = 1, 38 USB_8DEV_ENDP_DATA_TX, 39 USB_8DEV_ENDP_CMD_RX, 40 USB_8DEV_ENDP_CMD_TX 41 }; 42 43 /* device CAN clock */ 44 #define USB_8DEV_ABP_CLOCK 32000000 45 46 /* setup flags */ 47 #define USB_8DEV_SILENT 0x01 48 #define USB_8DEV_LOOPBACK 0x02 49 #define USB_8DEV_DISABLE_AUTO_RESTRANS 0x04 50 #define USB_8DEV_STATUS_FRAME 0x08 51 52 /* commands */ 53 enum usb_8dev_cmd { 54 USB_8DEV_RESET = 1, 55 USB_8DEV_OPEN, 56 USB_8DEV_CLOSE, 57 USB_8DEV_SET_SPEED, 58 USB_8DEV_SET_MASK_FILTER, 59 USB_8DEV_GET_STATUS, 60 USB_8DEV_GET_STATISTICS, 61 USB_8DEV_GET_SERIAL, 62 USB_8DEV_GET_SOFTW_VER, 63 USB_8DEV_GET_HARDW_VER, 64 USB_8DEV_RESET_TIMESTAMP, 65 USB_8DEV_GET_SOFTW_HARDW_VER 66 }; 67 68 /* command options */ 69 #define USB_8DEV_BAUD_MANUAL 0x09 70 #define USB_8DEV_CMD_START 0x11 71 #define USB_8DEV_CMD_END 0x22 72 73 #define USB_8DEV_CMD_SUCCESS 0 74 #define USB_8DEV_CMD_ERROR 255 75 76 #define USB_8DEV_CMD_TIMEOUT 1000 77 78 /* frames */ 79 #define USB_8DEV_DATA_START 0x55 80 #define USB_8DEV_DATA_END 0xAA 81 82 #define USB_8DEV_TYPE_CAN_FRAME 0 83 #define USB_8DEV_TYPE_ERROR_FRAME 3 84 85 #define USB_8DEV_EXTID 0x01 86 #define USB_8DEV_RTR 0x02 87 #define USB_8DEV_ERR_FLAG 0x04 88 89 /* status */ 90 #define USB_8DEV_STATUSMSG_OK 0x00 /* Normal condition. */ 91 #define USB_8DEV_STATUSMSG_OVERRUN 0x01 /* Overrun occurred when sending */ 92 #define USB_8DEV_STATUSMSG_BUSLIGHT 0x02 /* Error counter has reached 96 */ 93 #define USB_8DEV_STATUSMSG_BUSHEAVY 0x03 /* Error count. has reached 128 */ 94 #define USB_8DEV_STATUSMSG_BUSOFF 0x04 /* Device is in BUSOFF */ 95 #define USB_8DEV_STATUSMSG_STUFF 0x20 /* Stuff Error */ 96 #define USB_8DEV_STATUSMSG_FORM 0x21 /* Form Error */ 97 #define USB_8DEV_STATUSMSG_ACK 0x23 /* Ack Error */ 98 #define USB_8DEV_STATUSMSG_BIT0 0x24 /* Bit1 Error */ 99 #define USB_8DEV_STATUSMSG_BIT1 0x25 /* Bit0 Error */ 100 #define USB_8DEV_STATUSMSG_CRC 0x27 /* CRC Error */ 101 102 #define USB_8DEV_RP_MASK 0x7F /* Mask for Receive Error Bit */ 103 104 105 /* table of devices that work with this driver */ 106 static const struct usb_device_id usb_8dev_table[] = { 107 { USB_DEVICE(USB_8DEV_VENDOR_ID, USB_8DEV_PRODUCT_ID) }, 108 { } /* Terminating entry */ 109 }; 110 111 MODULE_DEVICE_TABLE(usb, usb_8dev_table); 112 113 struct usb_8dev_tx_urb_context { 114 struct usb_8dev_priv *priv; 115 116 u32 echo_index; 117 u8 dlc; 118 }; 119 120 /* Structure to hold all of our device specific stuff */ 121 struct usb_8dev_priv { 122 struct can_priv can; /* must be the first member */ 123 124 struct sk_buff *echo_skb[MAX_TX_URBS]; 125 126 struct usb_device *udev; 127 struct net_device *netdev; 128 129 atomic_t active_tx_urbs; 130 struct usb_anchor tx_submitted; 131 struct usb_8dev_tx_urb_context tx_contexts[MAX_TX_URBS]; 132 133 struct usb_anchor rx_submitted; 134 135 struct can_berr_counter bec; 136 137 u8 *cmd_msg_buffer; 138 139 struct mutex usb_8dev_cmd_lock; 140 141 }; 142 143 /* tx frame */ 144 struct __packed usb_8dev_tx_msg { 145 u8 begin; 146 u8 flags; /* RTR and EXT_ID flag */ 147 __be32 id; /* upper 3 bits not used */ 148 u8 dlc; /* data length code 0-8 bytes */ 149 u8 data[8]; /* 64-bit data */ 150 u8 end; 151 }; 152 153 /* rx frame */ 154 struct __packed usb_8dev_rx_msg { 155 u8 begin; 156 u8 type; /* frame type */ 157 u8 flags; /* RTR and EXT_ID flag */ 158 __be32 id; /* upper 3 bits not used */ 159 u8 dlc; /* data length code 0-8 bytes */ 160 u8 data[8]; /* 64-bit data */ 161 __be32 timestamp; /* 32-bit timestamp */ 162 u8 end; 163 }; 164 165 /* command frame */ 166 struct __packed usb_8dev_cmd_msg { 167 u8 begin; 168 u8 channel; /* unknown - always 0 */ 169 u8 command; /* command to execute */ 170 u8 opt1; /* optional parameter / return value */ 171 u8 opt2; /* optional parameter 2 */ 172 u8 data[10]; /* optional parameter and data */ 173 u8 end; 174 }; 175 176 static int usb_8dev_send_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size) 177 { 178 int actual_length; 179 180 return usb_bulk_msg(priv->udev, 181 usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_TX), 182 msg, size, &actual_length, USB_8DEV_CMD_TIMEOUT); 183 } 184 185 static int usb_8dev_wait_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size, 186 int *actual_length) 187 { 188 return usb_bulk_msg(priv->udev, 189 usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_RX), 190 msg, size, actual_length, USB_8DEV_CMD_TIMEOUT); 191 } 192 193 /* Send command to device and receive result. 194 * Command was successful when opt1 = 0. 195 */ 196 static int usb_8dev_send_cmd(struct usb_8dev_priv *priv, 197 struct usb_8dev_cmd_msg *out, 198 struct usb_8dev_cmd_msg *in) 199 { 200 int err; 201 int num_bytes_read; 202 struct net_device *netdev; 203 204 netdev = priv->netdev; 205 206 out->begin = USB_8DEV_CMD_START; 207 out->end = USB_8DEV_CMD_END; 208 209 mutex_lock(&priv->usb_8dev_cmd_lock); 210 211 memcpy(priv->cmd_msg_buffer, out, 212 sizeof(struct usb_8dev_cmd_msg)); 213 214 err = usb_8dev_send_cmd_msg(priv, priv->cmd_msg_buffer, 215 sizeof(struct usb_8dev_cmd_msg)); 216 if (err < 0) { 217 netdev_err(netdev, "sending command message failed\n"); 218 goto failed; 219 } 220 221 err = usb_8dev_wait_cmd_msg(priv, priv->cmd_msg_buffer, 222 sizeof(struct usb_8dev_cmd_msg), 223 &num_bytes_read); 224 if (err < 0) { 225 netdev_err(netdev, "no command message answer\n"); 226 goto failed; 227 } 228 229 memcpy(in, priv->cmd_msg_buffer, sizeof(struct usb_8dev_cmd_msg)); 230 231 if (in->begin != USB_8DEV_CMD_START || in->end != USB_8DEV_CMD_END || 232 num_bytes_read != 16 || in->opt1 != 0) 233 err = -EPROTO; 234 235 failed: 236 mutex_unlock(&priv->usb_8dev_cmd_lock); 237 return err; 238 } 239 240 /* Send open command to device */ 241 static int usb_8dev_cmd_open(struct usb_8dev_priv *priv) 242 { 243 struct can_bittiming *bt = &priv->can.bittiming; 244 struct usb_8dev_cmd_msg outmsg; 245 struct usb_8dev_cmd_msg inmsg; 246 u32 ctrlmode = priv->can.ctrlmode; 247 u32 flags = USB_8DEV_STATUS_FRAME; 248 __be32 beflags; 249 __be16 bebrp; 250 251 memset(&outmsg, 0, sizeof(outmsg)); 252 outmsg.command = USB_8DEV_OPEN; 253 outmsg.opt1 = USB_8DEV_BAUD_MANUAL; 254 outmsg.data[0] = bt->prop_seg + bt->phase_seg1; 255 outmsg.data[1] = bt->phase_seg2; 256 outmsg.data[2] = bt->sjw; 257 258 /* BRP */ 259 bebrp = cpu_to_be16((u16)bt->brp); 260 memcpy(&outmsg.data[3], &bebrp, sizeof(bebrp)); 261 262 /* flags */ 263 if (ctrlmode & CAN_CTRLMODE_LOOPBACK) 264 flags |= USB_8DEV_LOOPBACK; 265 if (ctrlmode & CAN_CTRLMODE_LISTENONLY) 266 flags |= USB_8DEV_SILENT; 267 if (ctrlmode & CAN_CTRLMODE_ONE_SHOT) 268 flags |= USB_8DEV_DISABLE_AUTO_RESTRANS; 269 270 beflags = cpu_to_be32(flags); 271 memcpy(&outmsg.data[5], &beflags, sizeof(beflags)); 272 273 return usb_8dev_send_cmd(priv, &outmsg, &inmsg); 274 } 275 276 /* Send close command to device */ 277 static int usb_8dev_cmd_close(struct usb_8dev_priv *priv) 278 { 279 struct usb_8dev_cmd_msg inmsg; 280 struct usb_8dev_cmd_msg outmsg = { 281 .channel = 0, 282 .command = USB_8DEV_CLOSE, 283 .opt1 = 0, 284 .opt2 = 0 285 }; 286 287 return usb_8dev_send_cmd(priv, &outmsg, &inmsg); 288 } 289 290 /* Get firmware and hardware version */ 291 static int usb_8dev_cmd_version(struct usb_8dev_priv *priv, u32 *res) 292 { 293 struct usb_8dev_cmd_msg inmsg; 294 struct usb_8dev_cmd_msg outmsg = { 295 .channel = 0, 296 .command = USB_8DEV_GET_SOFTW_HARDW_VER, 297 .opt1 = 0, 298 .opt2 = 0 299 }; 300 301 int err = usb_8dev_send_cmd(priv, &outmsg, &inmsg); 302 if (err) 303 return err; 304 305 *res = be32_to_cpup((__be32 *)inmsg.data); 306 307 return err; 308 } 309 310 /* Set network device mode 311 * 312 * Maybe we should leave this function empty, because the device 313 * set mode variable with open command. 314 */ 315 static int usb_8dev_set_mode(struct net_device *netdev, enum can_mode mode) 316 { 317 struct usb_8dev_priv *priv = netdev_priv(netdev); 318 int err = 0; 319 320 switch (mode) { 321 case CAN_MODE_START: 322 err = usb_8dev_cmd_open(priv); 323 if (err) 324 netdev_warn(netdev, "couldn't start device"); 325 break; 326 327 default: 328 return -EOPNOTSUPP; 329 } 330 331 return err; 332 } 333 334 /* Read error/status frames */ 335 static void usb_8dev_rx_err_msg(struct usb_8dev_priv *priv, 336 struct usb_8dev_rx_msg *msg) 337 { 338 struct can_frame *cf; 339 struct sk_buff *skb; 340 struct net_device_stats *stats = &priv->netdev->stats; 341 342 /* Error message: 343 * byte 0: Status 344 * byte 1: bit 7: Receive Passive 345 * byte 1: bit 0-6: Receive Error Counter 346 * byte 2: Transmit Error Counter 347 * byte 3: Always 0 (maybe reserved for future use) 348 */ 349 350 u8 state = msg->data[0]; 351 u8 rxerr = msg->data[1] & USB_8DEV_RP_MASK; 352 u8 txerr = msg->data[2]; 353 int rx_errors = 0; 354 int tx_errors = 0; 355 356 skb = alloc_can_err_skb(priv->netdev, &cf); 357 if (!skb) 358 return; 359 360 switch (state) { 361 case USB_8DEV_STATUSMSG_OK: 362 priv->can.state = CAN_STATE_ERROR_ACTIVE; 363 cf->can_id |= CAN_ERR_PROT; 364 cf->data[2] = CAN_ERR_PROT_ACTIVE; 365 break; 366 case USB_8DEV_STATUSMSG_BUSOFF: 367 priv->can.state = CAN_STATE_BUS_OFF; 368 cf->can_id |= CAN_ERR_BUSOFF; 369 priv->can.can_stats.bus_off++; 370 can_bus_off(priv->netdev); 371 break; 372 case USB_8DEV_STATUSMSG_OVERRUN: 373 case USB_8DEV_STATUSMSG_BUSLIGHT: 374 case USB_8DEV_STATUSMSG_BUSHEAVY: 375 cf->can_id |= CAN_ERR_CRTL; 376 break; 377 default: 378 priv->can.state = CAN_STATE_ERROR_WARNING; 379 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; 380 priv->can.can_stats.bus_error++; 381 break; 382 } 383 384 switch (state) { 385 case USB_8DEV_STATUSMSG_OK: 386 case USB_8DEV_STATUSMSG_BUSOFF: 387 break; 388 case USB_8DEV_STATUSMSG_ACK: 389 cf->can_id |= CAN_ERR_ACK; 390 tx_errors = 1; 391 break; 392 case USB_8DEV_STATUSMSG_CRC: 393 cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ; 394 rx_errors = 1; 395 break; 396 case USB_8DEV_STATUSMSG_BIT0: 397 cf->data[2] |= CAN_ERR_PROT_BIT0; 398 tx_errors = 1; 399 break; 400 case USB_8DEV_STATUSMSG_BIT1: 401 cf->data[2] |= CAN_ERR_PROT_BIT1; 402 tx_errors = 1; 403 break; 404 case USB_8DEV_STATUSMSG_FORM: 405 cf->data[2] |= CAN_ERR_PROT_FORM; 406 rx_errors = 1; 407 break; 408 case USB_8DEV_STATUSMSG_STUFF: 409 cf->data[2] |= CAN_ERR_PROT_STUFF; 410 rx_errors = 1; 411 break; 412 case USB_8DEV_STATUSMSG_OVERRUN: 413 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 414 stats->rx_over_errors++; 415 rx_errors = 1; 416 break; 417 case USB_8DEV_STATUSMSG_BUSLIGHT: 418 priv->can.state = CAN_STATE_ERROR_WARNING; 419 cf->data[1] = (txerr > rxerr) ? 420 CAN_ERR_CRTL_TX_WARNING : 421 CAN_ERR_CRTL_RX_WARNING; 422 priv->can.can_stats.error_warning++; 423 break; 424 case USB_8DEV_STATUSMSG_BUSHEAVY: 425 priv->can.state = CAN_STATE_ERROR_PASSIVE; 426 cf->data[1] = (txerr > rxerr) ? 427 CAN_ERR_CRTL_TX_PASSIVE : 428 CAN_ERR_CRTL_RX_PASSIVE; 429 priv->can.can_stats.error_passive++; 430 break; 431 default: 432 netdev_warn(priv->netdev, 433 "Unknown status/error message (%d)\n", state); 434 break; 435 } 436 437 if (tx_errors) { 438 cf->data[2] |= CAN_ERR_PROT_TX; 439 stats->tx_errors++; 440 } 441 442 if (rx_errors) 443 stats->rx_errors++; 444 445 cf->data[6] = txerr; 446 cf->data[7] = rxerr; 447 448 priv->bec.txerr = txerr; 449 priv->bec.rxerr = rxerr; 450 451 stats->rx_packets++; 452 stats->rx_bytes += cf->len; 453 netif_rx(skb); 454 } 455 456 /* Read data and status frames */ 457 static void usb_8dev_rx_can_msg(struct usb_8dev_priv *priv, 458 struct usb_8dev_rx_msg *msg) 459 { 460 struct can_frame *cf; 461 struct sk_buff *skb; 462 struct net_device_stats *stats = &priv->netdev->stats; 463 464 if (msg->type == USB_8DEV_TYPE_ERROR_FRAME && 465 msg->flags == USB_8DEV_ERR_FLAG) { 466 usb_8dev_rx_err_msg(priv, msg); 467 } else if (msg->type == USB_8DEV_TYPE_CAN_FRAME) { 468 skb = alloc_can_skb(priv->netdev, &cf); 469 if (!skb) 470 return; 471 472 cf->can_id = be32_to_cpu(msg->id); 473 can_frame_set_cc_len(cf, msg->dlc & 0xF, priv->can.ctrlmode); 474 475 if (msg->flags & USB_8DEV_EXTID) 476 cf->can_id |= CAN_EFF_FLAG; 477 478 if (msg->flags & USB_8DEV_RTR) 479 cf->can_id |= CAN_RTR_FLAG; 480 else 481 memcpy(cf->data, msg->data, cf->len); 482 483 stats->rx_packets++; 484 stats->rx_bytes += cf->len; 485 netif_rx(skb); 486 487 can_led_event(priv->netdev, CAN_LED_EVENT_RX); 488 } else { 489 netdev_warn(priv->netdev, "frame type %d unknown", 490 msg->type); 491 } 492 493 } 494 495 /* Callback for reading data from device 496 * 497 * Check urb status, call read function and resubmit urb read operation. 498 */ 499 static void usb_8dev_read_bulk_callback(struct urb *urb) 500 { 501 struct usb_8dev_priv *priv = urb->context; 502 struct net_device *netdev; 503 int retval; 504 int pos = 0; 505 506 netdev = priv->netdev; 507 508 if (!netif_device_present(netdev)) 509 return; 510 511 switch (urb->status) { 512 case 0: /* success */ 513 break; 514 515 case -ENOENT: 516 case -EPIPE: 517 case -EPROTO: 518 case -ESHUTDOWN: 519 return; 520 521 default: 522 netdev_info(netdev, "Rx URB aborted (%d)\n", 523 urb->status); 524 goto resubmit_urb; 525 } 526 527 while (pos < urb->actual_length) { 528 struct usb_8dev_rx_msg *msg; 529 530 if (pos + sizeof(struct usb_8dev_rx_msg) > urb->actual_length) { 531 netdev_err(priv->netdev, "format error\n"); 532 break; 533 } 534 535 msg = (struct usb_8dev_rx_msg *)(urb->transfer_buffer + pos); 536 usb_8dev_rx_can_msg(priv, msg); 537 538 pos += sizeof(struct usb_8dev_rx_msg); 539 } 540 541 resubmit_urb: 542 usb_fill_bulk_urb(urb, priv->udev, 543 usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_RX), 544 urb->transfer_buffer, RX_BUFFER_SIZE, 545 usb_8dev_read_bulk_callback, priv); 546 547 retval = usb_submit_urb(urb, GFP_ATOMIC); 548 549 if (retval == -ENODEV) 550 netif_device_detach(netdev); 551 else if (retval) 552 netdev_err(netdev, 553 "failed resubmitting read bulk urb: %d\n", retval); 554 } 555 556 /* Callback handler for write operations 557 * 558 * Free allocated buffers, check transmit status and 559 * calculate statistic. 560 */ 561 static void usb_8dev_write_bulk_callback(struct urb *urb) 562 { 563 struct usb_8dev_tx_urb_context *context = urb->context; 564 struct usb_8dev_priv *priv; 565 struct net_device *netdev; 566 567 BUG_ON(!context); 568 569 priv = context->priv; 570 netdev = priv->netdev; 571 572 /* free up our allocated buffer */ 573 usb_free_coherent(urb->dev, urb->transfer_buffer_length, 574 urb->transfer_buffer, urb->transfer_dma); 575 576 atomic_dec(&priv->active_tx_urbs); 577 578 if (!netif_device_present(netdev)) 579 return; 580 581 if (urb->status) 582 netdev_info(netdev, "Tx URB aborted (%d)\n", 583 urb->status); 584 585 netdev->stats.tx_packets++; 586 netdev->stats.tx_bytes += context->dlc; 587 588 can_get_echo_skb(netdev, context->echo_index); 589 590 can_led_event(netdev, CAN_LED_EVENT_TX); 591 592 /* Release context */ 593 context->echo_index = MAX_TX_URBS; 594 595 netif_wake_queue(netdev); 596 } 597 598 /* Send data to device */ 599 static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb, 600 struct net_device *netdev) 601 { 602 struct usb_8dev_priv *priv = netdev_priv(netdev); 603 struct net_device_stats *stats = &netdev->stats; 604 struct can_frame *cf = (struct can_frame *) skb->data; 605 struct usb_8dev_tx_msg *msg; 606 struct urb *urb; 607 struct usb_8dev_tx_urb_context *context = NULL; 608 u8 *buf; 609 int i, err; 610 size_t size = sizeof(struct usb_8dev_tx_msg); 611 612 if (can_dropped_invalid_skb(netdev, skb)) 613 return NETDEV_TX_OK; 614 615 /* create a URB, and a buffer for it, and copy the data to the URB */ 616 urb = usb_alloc_urb(0, GFP_ATOMIC); 617 if (!urb) 618 goto nomem; 619 620 buf = usb_alloc_coherent(priv->udev, size, GFP_ATOMIC, 621 &urb->transfer_dma); 622 if (!buf) { 623 netdev_err(netdev, "No memory left for USB buffer\n"); 624 goto nomembuf; 625 } 626 627 memset(buf, 0, size); 628 629 msg = (struct usb_8dev_tx_msg *)buf; 630 msg->begin = USB_8DEV_DATA_START; 631 msg->flags = 0x00; 632 633 if (cf->can_id & CAN_RTR_FLAG) 634 msg->flags |= USB_8DEV_RTR; 635 636 if (cf->can_id & CAN_EFF_FLAG) 637 msg->flags |= USB_8DEV_EXTID; 638 639 msg->id = cpu_to_be32(cf->can_id & CAN_ERR_MASK); 640 msg->dlc = can_get_cc_dlc(cf, priv->can.ctrlmode); 641 memcpy(msg->data, cf->data, cf->len); 642 msg->end = USB_8DEV_DATA_END; 643 644 for (i = 0; i < MAX_TX_URBS; i++) { 645 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) { 646 context = &priv->tx_contexts[i]; 647 break; 648 } 649 } 650 651 /* May never happen! When this happens we'd more URBs in flight as 652 * allowed (MAX_TX_URBS). 653 */ 654 if (!context) 655 goto nofreecontext; 656 657 context->priv = priv; 658 context->echo_index = i; 659 context->dlc = cf->len; 660 661 usb_fill_bulk_urb(urb, priv->udev, 662 usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_TX), 663 buf, size, usb_8dev_write_bulk_callback, context); 664 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 665 usb_anchor_urb(urb, &priv->tx_submitted); 666 667 can_put_echo_skb(skb, netdev, context->echo_index); 668 669 atomic_inc(&priv->active_tx_urbs); 670 671 err = usb_submit_urb(urb, GFP_ATOMIC); 672 if (unlikely(err)) 673 goto failed; 674 else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS) 675 /* Slow down tx path */ 676 netif_stop_queue(netdev); 677 678 /* Release our reference to this URB, the USB core will eventually free 679 * it entirely. 680 */ 681 usb_free_urb(urb); 682 683 return NETDEV_TX_OK; 684 685 nofreecontext: 686 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma); 687 usb_free_urb(urb); 688 689 netdev_warn(netdev, "couldn't find free context"); 690 691 return NETDEV_TX_BUSY; 692 693 failed: 694 can_free_echo_skb(netdev, context->echo_index); 695 696 usb_unanchor_urb(urb); 697 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma); 698 699 atomic_dec(&priv->active_tx_urbs); 700 701 if (err == -ENODEV) 702 netif_device_detach(netdev); 703 else 704 netdev_warn(netdev, "failed tx_urb %d\n", err); 705 706 nomembuf: 707 usb_free_urb(urb); 708 709 nomem: 710 dev_kfree_skb(skb); 711 stats->tx_dropped++; 712 713 return NETDEV_TX_OK; 714 } 715 716 static int usb_8dev_get_berr_counter(const struct net_device *netdev, 717 struct can_berr_counter *bec) 718 { 719 struct usb_8dev_priv *priv = netdev_priv(netdev); 720 721 bec->txerr = priv->bec.txerr; 722 bec->rxerr = priv->bec.rxerr; 723 724 return 0; 725 } 726 727 /* Start USB device */ 728 static int usb_8dev_start(struct usb_8dev_priv *priv) 729 { 730 struct net_device *netdev = priv->netdev; 731 int err, i; 732 733 for (i = 0; i < MAX_RX_URBS; i++) { 734 struct urb *urb = NULL; 735 u8 *buf; 736 737 /* create a URB, and a buffer for it */ 738 urb = usb_alloc_urb(0, GFP_KERNEL); 739 if (!urb) { 740 err = -ENOMEM; 741 break; 742 } 743 744 buf = usb_alloc_coherent(priv->udev, RX_BUFFER_SIZE, GFP_KERNEL, 745 &urb->transfer_dma); 746 if (!buf) { 747 netdev_err(netdev, "No memory left for USB buffer\n"); 748 usb_free_urb(urb); 749 err = -ENOMEM; 750 break; 751 } 752 753 usb_fill_bulk_urb(urb, priv->udev, 754 usb_rcvbulkpipe(priv->udev, 755 USB_8DEV_ENDP_DATA_RX), 756 buf, RX_BUFFER_SIZE, 757 usb_8dev_read_bulk_callback, priv); 758 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 759 usb_anchor_urb(urb, &priv->rx_submitted); 760 761 err = usb_submit_urb(urb, GFP_KERNEL); 762 if (err) { 763 usb_unanchor_urb(urb); 764 usb_free_coherent(priv->udev, RX_BUFFER_SIZE, buf, 765 urb->transfer_dma); 766 usb_free_urb(urb); 767 break; 768 } 769 770 /* Drop reference, USB core will take care of freeing it */ 771 usb_free_urb(urb); 772 } 773 774 /* Did we submit any URBs */ 775 if (i == 0) { 776 netdev_warn(netdev, "couldn't setup read URBs\n"); 777 return err; 778 } 779 780 /* Warn if we've couldn't transmit all the URBs */ 781 if (i < MAX_RX_URBS) 782 netdev_warn(netdev, "rx performance may be slow\n"); 783 784 err = usb_8dev_cmd_open(priv); 785 if (err) 786 goto failed; 787 788 priv->can.state = CAN_STATE_ERROR_ACTIVE; 789 790 return 0; 791 792 failed: 793 if (err == -ENODEV) 794 netif_device_detach(priv->netdev); 795 796 netdev_warn(netdev, "couldn't submit control: %d\n", err); 797 798 return err; 799 } 800 801 /* Open USB device */ 802 static int usb_8dev_open(struct net_device *netdev) 803 { 804 struct usb_8dev_priv *priv = netdev_priv(netdev); 805 int err; 806 807 /* common open */ 808 err = open_candev(netdev); 809 if (err) 810 return err; 811 812 can_led_event(netdev, CAN_LED_EVENT_OPEN); 813 814 /* finally start device */ 815 err = usb_8dev_start(priv); 816 if (err) { 817 if (err == -ENODEV) 818 netif_device_detach(priv->netdev); 819 820 netdev_warn(netdev, "couldn't start device: %d\n", 821 err); 822 823 close_candev(netdev); 824 825 return err; 826 } 827 828 netif_start_queue(netdev); 829 830 return 0; 831 } 832 833 static void unlink_all_urbs(struct usb_8dev_priv *priv) 834 { 835 int i; 836 837 usb_kill_anchored_urbs(&priv->rx_submitted); 838 839 usb_kill_anchored_urbs(&priv->tx_submitted); 840 atomic_set(&priv->active_tx_urbs, 0); 841 842 for (i = 0; i < MAX_TX_URBS; i++) 843 priv->tx_contexts[i].echo_index = MAX_TX_URBS; 844 } 845 846 /* Close USB device */ 847 static int usb_8dev_close(struct net_device *netdev) 848 { 849 struct usb_8dev_priv *priv = netdev_priv(netdev); 850 int err = 0; 851 852 /* Send CLOSE command to CAN controller */ 853 err = usb_8dev_cmd_close(priv); 854 if (err) 855 netdev_warn(netdev, "couldn't stop device"); 856 857 priv->can.state = CAN_STATE_STOPPED; 858 859 netif_stop_queue(netdev); 860 861 /* Stop polling */ 862 unlink_all_urbs(priv); 863 864 close_candev(netdev); 865 866 can_led_event(netdev, CAN_LED_EVENT_STOP); 867 868 return err; 869 } 870 871 static const struct net_device_ops usb_8dev_netdev_ops = { 872 .ndo_open = usb_8dev_open, 873 .ndo_stop = usb_8dev_close, 874 .ndo_start_xmit = usb_8dev_start_xmit, 875 .ndo_change_mtu = can_change_mtu, 876 }; 877 878 static const struct can_bittiming_const usb_8dev_bittiming_const = { 879 .name = "usb_8dev", 880 .tseg1_min = 1, 881 .tseg1_max = 16, 882 .tseg2_min = 1, 883 .tseg2_max = 8, 884 .sjw_max = 4, 885 .brp_min = 1, 886 .brp_max = 1024, 887 .brp_inc = 1, 888 }; 889 890 /* Probe USB device 891 * 892 * Check device and firmware. 893 * Set supported modes and bittiming constants. 894 * Allocate some memory. 895 */ 896 static int usb_8dev_probe(struct usb_interface *intf, 897 const struct usb_device_id *id) 898 { 899 struct net_device *netdev; 900 struct usb_8dev_priv *priv; 901 int i, err = -ENOMEM; 902 u32 version; 903 char buf[18]; 904 struct usb_device *usbdev = interface_to_usbdev(intf); 905 906 /* product id looks strange, better we also check iProduct string */ 907 if (usb_string(usbdev, usbdev->descriptor.iProduct, buf, 908 sizeof(buf)) > 0 && strcmp(buf, "USB2CAN converter")) { 909 dev_info(&usbdev->dev, "ignoring: not an USB2CAN converter\n"); 910 return -ENODEV; 911 } 912 913 netdev = alloc_candev(sizeof(struct usb_8dev_priv), MAX_TX_URBS); 914 if (!netdev) { 915 dev_err(&intf->dev, "Couldn't alloc candev\n"); 916 return -ENOMEM; 917 } 918 919 priv = netdev_priv(netdev); 920 921 priv->udev = usbdev; 922 priv->netdev = netdev; 923 924 priv->can.state = CAN_STATE_STOPPED; 925 priv->can.clock.freq = USB_8DEV_ABP_CLOCK; 926 priv->can.bittiming_const = &usb_8dev_bittiming_const; 927 priv->can.do_set_mode = usb_8dev_set_mode; 928 priv->can.do_get_berr_counter = usb_8dev_get_berr_counter; 929 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | 930 CAN_CTRLMODE_LISTENONLY | 931 CAN_CTRLMODE_ONE_SHOT | 932 CAN_CTRLMODE_CC_LEN8_DLC; 933 934 netdev->netdev_ops = &usb_8dev_netdev_ops; 935 936 netdev->flags |= IFF_ECHO; /* we support local echo */ 937 938 init_usb_anchor(&priv->rx_submitted); 939 940 init_usb_anchor(&priv->tx_submitted); 941 atomic_set(&priv->active_tx_urbs, 0); 942 943 for (i = 0; i < MAX_TX_URBS; i++) 944 priv->tx_contexts[i].echo_index = MAX_TX_URBS; 945 946 priv->cmd_msg_buffer = devm_kzalloc(&intf->dev, sizeof(struct usb_8dev_cmd_msg), 947 GFP_KERNEL); 948 if (!priv->cmd_msg_buffer) 949 goto cleanup_candev; 950 951 usb_set_intfdata(intf, priv); 952 953 SET_NETDEV_DEV(netdev, &intf->dev); 954 955 mutex_init(&priv->usb_8dev_cmd_lock); 956 957 err = register_candev(netdev); 958 if (err) { 959 netdev_err(netdev, 960 "couldn't register CAN device: %d\n", err); 961 goto cleanup_candev; 962 } 963 964 err = usb_8dev_cmd_version(priv, &version); 965 if (err) { 966 netdev_err(netdev, "can't get firmware version\n"); 967 goto cleanup_unregister_candev; 968 } else { 969 netdev_info(netdev, 970 "firmware: %d.%d, hardware: %d.%d\n", 971 (version>>24) & 0xff, (version>>16) & 0xff, 972 (version>>8) & 0xff, version & 0xff); 973 } 974 975 devm_can_led_init(netdev); 976 977 return 0; 978 979 cleanup_unregister_candev: 980 unregister_netdev(priv->netdev); 981 982 cleanup_candev: 983 free_candev(netdev); 984 985 return err; 986 987 } 988 989 /* Called by the usb core when driver is unloaded or device is removed */ 990 static void usb_8dev_disconnect(struct usb_interface *intf) 991 { 992 struct usb_8dev_priv *priv = usb_get_intfdata(intf); 993 994 usb_set_intfdata(intf, NULL); 995 996 if (priv) { 997 netdev_info(priv->netdev, "device disconnected\n"); 998 999 unregister_netdev(priv->netdev); 1000 unlink_all_urbs(priv); 1001 free_candev(priv->netdev); 1002 } 1003 1004 } 1005 1006 static struct usb_driver usb_8dev_driver = { 1007 .name = "usb_8dev", 1008 .probe = usb_8dev_probe, 1009 .disconnect = usb_8dev_disconnect, 1010 .id_table = usb_8dev_table, 1011 }; 1012 1013 module_usb_driver(usb_8dev_driver); 1014 1015 MODULE_AUTHOR("Bernd Krumboeck <krumboeck@universalnet.at>"); 1016 MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces"); 1017 MODULE_LICENSE("GPL v2"); 1018