usb_8dev.c revision 0024d8ad1639e32d717445c69ca813fd19c2a91c
1/* 2 * CAN driver for "8 devices" USB2CAN converter 3 * 4 * Copyright (C) 2012 Bernd Krumboeck (krumboeck@universalnet.at) 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License as published 8 * by the Free Software Foundation; version 2 of the License. 9 * 10 * This program is distributed in the hope that it will be useful, but 11 * WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License along 16 * with this program. 17 * 18 * This driver is inspired by the 3.2.0 version of drivers/net/can/usb/ems_usb.c 19 * and drivers/net/can/usb/esd_usb2.c 20 * 21 * Many thanks to Gerhard Bertelsmann (info@gerhard-bertelsmann.de) 22 * for testing and fixing this driver. Also many thanks to "8 devices", 23 * who were very cooperative and answered my questions. 24 */ 25 26#include <linux/init.h> 27#include <linux/signal.h> 28#include <linux/slab.h> 29#include <linux/module.h> 30#include <linux/netdevice.h> 31#include <linux/usb.h> 32 33#include <linux/can.h> 34#include <linux/can/dev.h> 35#include <linux/can/error.h> 36 37/* driver constants */ 38#define MAX_RX_URBS 20 39#define MAX_TX_URBS 20 40#define RX_BUFFER_SIZE 64 41 42/* vendor and product id */ 43#define USB_8DEV_VENDOR_ID 0x0483 44#define USB_8DEV_PRODUCT_ID 0x1234 45 46/* endpoints */ 47enum usb_8dev_endpoint { 48 USB_8DEV_ENDP_DATA_RX = 1, 49 USB_8DEV_ENDP_DATA_TX, 50 USB_8DEV_ENDP_CMD_RX, 51 USB_8DEV_ENDP_CMD_TX 52}; 53 54/* device CAN clock */ 55#define USB_8DEV_ABP_CLOCK 32000000 56 57/* setup flags */ 58#define USB_8DEV_SILENT 0x01 59#define USB_8DEV_LOOPBACK 0x02 60#define USB_8DEV_DISABLE_AUTO_RESTRANS 0x04 61#define USB_8DEV_STATUS_FRAME 0x08 62 63/* commands */ 64enum usb_8dev_cmd { 65 USB_8DEV_RESET = 1, 66 USB_8DEV_OPEN, 67 USB_8DEV_CLOSE, 68 USB_8DEV_SET_SPEED, 69 USB_8DEV_SET_MASK_FILTER, 70 USB_8DEV_GET_STATUS, 71 USB_8DEV_GET_STATISTICS, 72 USB_8DEV_GET_SERIAL, 73 USB_8DEV_GET_SOFTW_VER, 74 USB_8DEV_GET_HARDW_VER, 75 USB_8DEV_RESET_TIMESTAMP, 76 USB_8DEV_GET_SOFTW_HARDW_VER 77}; 78 79/* command options */ 80#define USB_8DEV_BAUD_MANUAL 0x09 81#define USB_8DEV_CMD_START 0x11 82#define USB_8DEV_CMD_END 0x22 83 84#define USB_8DEV_CMD_SUCCESS 0 85#define USB_8DEV_CMD_ERROR 255 86 87#define USB_8DEV_CMD_TIMEOUT 1000 88 89/* frames */ 90#define USB_8DEV_DATA_START 0x55 91#define USB_8DEV_DATA_END 0xAA 92 93#define USB_8DEV_TYPE_CAN_FRAME 0 94#define USB_8DEV_TYPE_ERROR_FRAME 3 95 96#define USB_8DEV_EXTID 0x01 97#define USB_8DEV_RTR 0x02 98#define USB_8DEV_ERR_FLAG 0x04 99 100/* status */ 101#define USB_8DEV_STATUSMSG_OK 0x00 /* Normal condition. */ 102#define USB_8DEV_STATUSMSG_OVERRUN 0x01 /* Overrun occured when sending */ 103#define USB_8DEV_STATUSMSG_BUSLIGHT 0x02 /* Error counter has reached 96 */ 104#define USB_8DEV_STATUSMSG_BUSHEAVY 0x03 /* Error count. has reached 128 */ 105#define USB_8DEV_STATUSMSG_BUSOFF 0x04 /* Device is in BUSOFF */ 106#define USB_8DEV_STATUSMSG_STUFF 0x20 /* Stuff Error */ 107#define USB_8DEV_STATUSMSG_FORM 0x21 /* Form Error */ 108#define USB_8DEV_STATUSMSG_ACK 0x23 /* Ack Error */ 109#define USB_8DEV_STATUSMSG_BIT0 0x24 /* Bit1 Error */ 110#define USB_8DEV_STATUSMSG_BIT1 0x25 /* Bit0 Error */ 111#define USB_8DEV_STATUSMSG_CRC 0x27 /* CRC Error */ 112 113#define USB_8DEV_RP_MASK 0x7F /* Mask for Receive Error Bit */ 114 115 116/* table of devices that work with this driver */ 117static const struct usb_device_id usb_8dev_table[] = { 118 { USB_DEVICE(USB_8DEV_VENDOR_ID, USB_8DEV_PRODUCT_ID) }, 119 { } /* Terminating entry */ 120}; 121 122MODULE_DEVICE_TABLE(usb, usb_8dev_table); 123 124struct usb_8dev_tx_urb_context { 125 struct usb_8dev_priv *priv; 126 127 u32 echo_index; 128 u8 dlc; 129}; 130 131/* Structure to hold all of our device specific stuff */ 132struct usb_8dev_priv { 133 struct can_priv can; /* must be the first member */ 134 135 struct sk_buff *echo_skb[MAX_TX_URBS]; 136 137 struct usb_device *udev; 138 struct net_device *netdev; 139 140 atomic_t active_tx_urbs; 141 struct usb_anchor tx_submitted; 142 struct usb_8dev_tx_urb_context tx_contexts[MAX_TX_URBS]; 143 144 struct usb_anchor rx_submitted; 145 146 struct can_berr_counter bec; 147 148 u8 *cmd_msg_buffer; 149 150 struct mutex usb_8dev_cmd_lock; 151 152}; 153 154/* tx frame */ 155struct __packed usb_8dev_tx_msg { 156 u8 begin; 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 u8 end; 162}; 163 164/* rx frame */ 165struct __packed usb_8dev_rx_msg { 166 u8 begin; 167 u8 type; /* frame type */ 168 u8 flags; /* RTR and EXT_ID flag */ 169 __be32 id; /* upper 3 bits not used */ 170 u8 dlc; /* data length code 0-8 bytes */ 171 u8 data[8]; /* 64-bit data */ 172 __be32 timestamp; /* 32-bit timestamp */ 173 u8 end; 174}; 175 176/* command frame */ 177struct __packed usb_8dev_cmd_msg { 178 u8 begin; 179 u8 channel; /* unkown - always 0 */ 180 u8 command; /* command to execute */ 181 u8 opt1; /* optional parameter / return value */ 182 u8 opt2; /* optional parameter 2 */ 183 u8 data[10]; /* optional parameter and data */ 184 u8 end; 185}; 186 187static int usb_8dev_send_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size) 188{ 189 int actual_length; 190 191 return usb_bulk_msg(priv->udev, 192 usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_TX), 193 msg, size, &actual_length, USB_8DEV_CMD_TIMEOUT); 194} 195 196static int usb_8dev_wait_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size, 197 int *actual_length) 198{ 199 return usb_bulk_msg(priv->udev, 200 usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_RX), 201 msg, size, actual_length, USB_8DEV_CMD_TIMEOUT); 202} 203 204/* Send command to device and receive result. 205 * Command was successful when opt1 = 0. 206 */ 207static int usb_8dev_send_cmd(struct usb_8dev_priv *priv, 208 struct usb_8dev_cmd_msg *out, 209 struct usb_8dev_cmd_msg *in) 210{ 211 int err; 212 int num_bytes_read; 213 struct net_device *netdev; 214 215 netdev = priv->netdev; 216 217 out->begin = USB_8DEV_CMD_START; 218 out->end = USB_8DEV_CMD_END; 219 220 mutex_lock(&priv->usb_8dev_cmd_lock); 221 222 memcpy(priv->cmd_msg_buffer, out, 223 sizeof(struct usb_8dev_cmd_msg)); 224 225 err = usb_8dev_send_cmd_msg(priv, priv->cmd_msg_buffer, 226 sizeof(struct usb_8dev_cmd_msg)); 227 if (err < 0) { 228 netdev_err(netdev, "sending command message failed\n"); 229 goto failed; 230 } 231 232 err = usb_8dev_wait_cmd_msg(priv, priv->cmd_msg_buffer, 233 sizeof(struct usb_8dev_cmd_msg), 234 &num_bytes_read); 235 if (err < 0) { 236 netdev_err(netdev, "no command message answer\n"); 237 goto failed; 238 } 239 240 memcpy(in, priv->cmd_msg_buffer, sizeof(struct usb_8dev_cmd_msg)); 241 242 if (in->begin != USB_8DEV_CMD_START || in->end != USB_8DEV_CMD_END || 243 num_bytes_read != 16 || in->opt1 != 0) 244 err = -EPROTO; 245 246failed: 247 mutex_unlock(&priv->usb_8dev_cmd_lock); 248 return err; 249} 250 251/* Send open command to device */ 252static int usb_8dev_cmd_open(struct usb_8dev_priv *priv) 253{ 254 struct can_bittiming *bt = &priv->can.bittiming; 255 struct usb_8dev_cmd_msg outmsg; 256 struct usb_8dev_cmd_msg inmsg; 257 u32 ctrlmode = priv->can.ctrlmode; 258 u32 flags = USB_8DEV_STATUS_FRAME; 259 __be32 beflags; 260 __be16 bebrp; 261 262 memset(&outmsg, 0, sizeof(outmsg)); 263 outmsg.command = USB_8DEV_OPEN; 264 outmsg.opt1 = USB_8DEV_BAUD_MANUAL; 265 outmsg.data[0] = bt->prop_seg + bt->phase_seg1; 266 outmsg.data[1] = bt->phase_seg2; 267 outmsg.data[2] = bt->sjw; 268 269 /* BRP */ 270 bebrp = cpu_to_be16((u16)bt->brp); 271 memcpy(&outmsg.data[3], &bebrp, sizeof(bebrp)); 272 273 /* flags */ 274 if (ctrlmode & CAN_CTRLMODE_LOOPBACK) 275 flags |= USB_8DEV_LOOPBACK; 276 if (ctrlmode & CAN_CTRLMODE_LISTENONLY) 277 flags |= USB_8DEV_SILENT; 278 if (ctrlmode & CAN_CTRLMODE_ONE_SHOT) 279 flags |= USB_8DEV_DISABLE_AUTO_RESTRANS; 280 281 beflags = cpu_to_be32(flags); 282 memcpy(&outmsg.data[5], &beflags, sizeof(beflags)); 283 284 return usb_8dev_send_cmd(priv, &outmsg, &inmsg); 285} 286 287/* Send close command to device */ 288static int usb_8dev_cmd_close(struct usb_8dev_priv *priv) 289{ 290 struct usb_8dev_cmd_msg inmsg; 291 struct usb_8dev_cmd_msg outmsg = { 292 .channel = 0, 293 .command = USB_8DEV_CLOSE, 294 .opt1 = 0, 295 .opt2 = 0 296 }; 297 298 return usb_8dev_send_cmd(priv, &outmsg, &inmsg); 299} 300 301/* Get firmware and hardware version */ 302static int usb_8dev_cmd_version(struct usb_8dev_priv *priv, u32 *res) 303{ 304 struct usb_8dev_cmd_msg inmsg; 305 struct usb_8dev_cmd_msg outmsg = { 306 .channel = 0, 307 .command = USB_8DEV_GET_SOFTW_HARDW_VER, 308 .opt1 = 0, 309 .opt2 = 0 310 }; 311 312 int err = usb_8dev_send_cmd(priv, &outmsg, &inmsg); 313 if (err) 314 return err; 315 316 *res = be32_to_cpup((__be32 *)inmsg.data); 317 318 return err; 319} 320 321/* Set network device mode 322 * 323 * Maybe we should leave this function empty, because the device 324 * set mode variable with open command. 325 */ 326static int usb_8dev_set_mode(struct net_device *netdev, enum can_mode mode) 327{ 328 struct usb_8dev_priv *priv = netdev_priv(netdev); 329 int err = 0; 330 331 switch (mode) { 332 case CAN_MODE_START: 333 err = usb_8dev_cmd_open(priv); 334 if (err) 335 netdev_warn(netdev, "couldn't start device"); 336 break; 337 338 default: 339 return -EOPNOTSUPP; 340 } 341 342 return err; 343} 344 345/* Read error/status frames */ 346static void usb_8dev_rx_err_msg(struct usb_8dev_priv *priv, 347 struct usb_8dev_rx_msg *msg) 348{ 349 struct can_frame *cf; 350 struct sk_buff *skb; 351 struct net_device_stats *stats = &priv->netdev->stats; 352 353 /* Error message: 354 * byte 0: Status 355 * byte 1: bit 7: Receive Passive 356 * byte 1: bit 0-6: Receive Error Counter 357 * byte 2: Transmit Error Counter 358 * byte 3: Always 0 (maybe reserved for future use) 359 */ 360 361 u8 state = msg->data[0]; 362 u8 rxerr = msg->data[1] & USB_8DEV_RP_MASK; 363 u8 txerr = msg->data[2]; 364 int rx_errors = 0; 365 int tx_errors = 0; 366 367 skb = alloc_can_err_skb(priv->netdev, &cf); 368 if (!skb) 369 return; 370 371 switch (state) { 372 case USB_8DEV_STATUSMSG_OK: 373 priv->can.state = CAN_STATE_ERROR_ACTIVE; 374 cf->can_id |= CAN_ERR_PROT; 375 cf->data[2] = CAN_ERR_PROT_ACTIVE; 376 break; 377 case USB_8DEV_STATUSMSG_BUSOFF: 378 priv->can.state = CAN_STATE_BUS_OFF; 379 cf->can_id |= CAN_ERR_BUSOFF; 380 can_bus_off(priv->netdev); 381 break; 382 case USB_8DEV_STATUSMSG_OVERRUN: 383 case USB_8DEV_STATUSMSG_BUSLIGHT: 384 case USB_8DEV_STATUSMSG_BUSHEAVY: 385 cf->can_id |= CAN_ERR_CRTL; 386 break; 387 default: 388 priv->can.state = CAN_STATE_ERROR_WARNING; 389 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; 390 priv->can.can_stats.bus_error++; 391 break; 392 } 393 394 switch (state) { 395 case USB_8DEV_STATUSMSG_OK: 396 case USB_8DEV_STATUSMSG_BUSOFF: 397 break; 398 case USB_8DEV_STATUSMSG_ACK: 399 cf->can_id |= CAN_ERR_ACK; 400 tx_errors = 1; 401 break; 402 case USB_8DEV_STATUSMSG_CRC: 403 cf->data[2] |= CAN_ERR_PROT_UNSPEC; 404 cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ | 405 CAN_ERR_PROT_LOC_CRC_DEL; 406 rx_errors = 1; 407 break; 408 case USB_8DEV_STATUSMSG_BIT0: 409 cf->data[2] |= CAN_ERR_PROT_BIT0; 410 tx_errors = 1; 411 break; 412 case USB_8DEV_STATUSMSG_BIT1: 413 cf->data[2] |= CAN_ERR_PROT_BIT1; 414 tx_errors = 1; 415 break; 416 case USB_8DEV_STATUSMSG_FORM: 417 cf->data[2] |= CAN_ERR_PROT_FORM; 418 rx_errors = 1; 419 break; 420 case USB_8DEV_STATUSMSG_STUFF: 421 cf->data[2] |= CAN_ERR_PROT_STUFF; 422 rx_errors = 1; 423 break; 424 case USB_8DEV_STATUSMSG_OVERRUN: 425 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 426 stats->rx_over_errors++; 427 rx_errors = 1; 428 break; 429 case USB_8DEV_STATUSMSG_BUSLIGHT: 430 priv->can.state = CAN_STATE_ERROR_WARNING; 431 cf->data[1] = (txerr > rxerr) ? 432 CAN_ERR_CRTL_TX_WARNING : 433 CAN_ERR_CRTL_RX_WARNING; 434 priv->can.can_stats.error_warning++; 435 break; 436 case USB_8DEV_STATUSMSG_BUSHEAVY: 437 priv->can.state = CAN_STATE_ERROR_PASSIVE; 438 cf->data[1] = (txerr > rxerr) ? 439 CAN_ERR_CRTL_TX_PASSIVE : 440 CAN_ERR_CRTL_RX_PASSIVE; 441 priv->can.can_stats.error_passive++; 442 break; 443 default: 444 netdev_warn(priv->netdev, 445 "Unknown status/error message (%d)\n", state); 446 break; 447 } 448 449 if (tx_errors) { 450 cf->data[2] |= CAN_ERR_PROT_TX; 451 stats->tx_errors++; 452 } 453 454 if (rx_errors) 455 stats->rx_errors++; 456 457 cf->data[6] = txerr; 458 cf->data[7] = rxerr; 459 460 priv->bec.txerr = txerr; 461 priv->bec.rxerr = rxerr; 462 463 netif_rx(skb); 464 465 stats->rx_packets++; 466 stats->rx_bytes += cf->can_dlc; 467} 468 469/* Read data and status frames */ 470static void usb_8dev_rx_can_msg(struct usb_8dev_priv *priv, 471 struct usb_8dev_rx_msg *msg) 472{ 473 struct can_frame *cf; 474 struct sk_buff *skb; 475 struct net_device_stats *stats = &priv->netdev->stats; 476 477 if (msg->type == USB_8DEV_TYPE_ERROR_FRAME && 478 msg->flags == USB_8DEV_ERR_FLAG) { 479 usb_8dev_rx_err_msg(priv, msg); 480 } else if (msg->type == USB_8DEV_TYPE_CAN_FRAME) { 481 skb = alloc_can_skb(priv->netdev, &cf); 482 if (!skb) 483 return; 484 485 cf->can_id = be32_to_cpu(msg->id); 486 cf->can_dlc = get_can_dlc(msg->dlc & 0xF); 487 488 if (msg->flags & USB_8DEV_EXTID) 489 cf->can_id |= CAN_EFF_FLAG; 490 491 if (msg->flags & USB_8DEV_RTR) 492 cf->can_id |= CAN_RTR_FLAG; 493 else 494 memcpy(cf->data, msg->data, cf->can_dlc); 495 496 netif_rx(skb); 497 498 stats->rx_packets++; 499 stats->rx_bytes += cf->can_dlc; 500 } else { 501 netdev_warn(priv->netdev, "frame type %d unknown", 502 msg->type); 503 } 504 505} 506 507/* Callback for reading data from device 508 * 509 * Check urb status, call read function and resubmit urb read operation. 510 */ 511static void usb_8dev_read_bulk_callback(struct urb *urb) 512{ 513 struct usb_8dev_priv *priv = urb->context; 514 struct net_device *netdev; 515 int retval; 516 int pos = 0; 517 518 netdev = priv->netdev; 519 520 if (!netif_device_present(netdev)) 521 return; 522 523 switch (urb->status) { 524 case 0: /* success */ 525 break; 526 527 case -ENOENT: 528 case -ESHUTDOWN: 529 return; 530 531 default: 532 netdev_info(netdev, "Rx URB aborted (%d)\n", 533 urb->status); 534 goto resubmit_urb; 535 } 536 537 while (pos < urb->actual_length) { 538 struct usb_8dev_rx_msg *msg; 539 540 if (pos + sizeof(struct usb_8dev_rx_msg) > urb->actual_length) { 541 netdev_err(priv->netdev, "format error\n"); 542 break; 543 } 544 545 msg = (struct usb_8dev_rx_msg *)(urb->transfer_buffer + pos); 546 usb_8dev_rx_can_msg(priv, msg); 547 548 pos += sizeof(struct usb_8dev_rx_msg); 549 } 550 551resubmit_urb: 552 usb_fill_bulk_urb(urb, priv->udev, 553 usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_RX), 554 urb->transfer_buffer, RX_BUFFER_SIZE, 555 usb_8dev_read_bulk_callback, priv); 556 557 retval = usb_submit_urb(urb, GFP_ATOMIC); 558 559 if (retval == -ENODEV) 560 netif_device_detach(netdev); 561 else if (retval) 562 netdev_err(netdev, 563 "failed resubmitting read bulk urb: %d\n", retval); 564} 565 566/* Callback handler for write operations 567 * 568 * Free allocated buffers, check transmit status and 569 * calculate statistic. 570 */ 571static void usb_8dev_write_bulk_callback(struct urb *urb) 572{ 573 struct usb_8dev_tx_urb_context *context = urb->context; 574 struct usb_8dev_priv *priv; 575 struct net_device *netdev; 576 577 BUG_ON(!context); 578 579 priv = context->priv; 580 netdev = priv->netdev; 581 582 /* free up our allocated buffer */ 583 usb_free_coherent(urb->dev, urb->transfer_buffer_length, 584 urb->transfer_buffer, urb->transfer_dma); 585 586 atomic_dec(&priv->active_tx_urbs); 587 588 if (!netif_device_present(netdev)) 589 return; 590 591 if (urb->status) 592 netdev_info(netdev, "Tx URB aborted (%d)\n", 593 urb->status); 594 595 netdev->stats.tx_packets++; 596 netdev->stats.tx_bytes += context->dlc; 597 598 can_get_echo_skb(netdev, context->echo_index); 599 600 /* Release context */ 601 context->echo_index = MAX_TX_URBS; 602 603 netif_wake_queue(netdev); 604} 605 606/* Send data to device */ 607static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb, 608 struct net_device *netdev) 609{ 610 struct usb_8dev_priv *priv = netdev_priv(netdev); 611 struct net_device_stats *stats = &netdev->stats; 612 struct can_frame *cf = (struct can_frame *) skb->data; 613 struct usb_8dev_tx_msg *msg; 614 struct urb *urb; 615 struct usb_8dev_tx_urb_context *context = NULL; 616 u8 *buf; 617 int i, err; 618 size_t size = sizeof(struct usb_8dev_tx_msg); 619 620 if (can_dropped_invalid_skb(netdev, skb)) 621 return NETDEV_TX_OK; 622 623 /* create a URB, and a buffer for it, and copy the data to the URB */ 624 urb = usb_alloc_urb(0, GFP_ATOMIC); 625 if (!urb) { 626 netdev_err(netdev, "No memory left for URBs\n"); 627 goto nomem; 628 } 629 630 buf = usb_alloc_coherent(priv->udev, size, GFP_ATOMIC, 631 &urb->transfer_dma); 632 if (!buf) { 633 netdev_err(netdev, "No memory left for USB buffer\n"); 634 goto nomembuf; 635 } 636 637 memset(buf, 0, size); 638 639 msg = (struct usb_8dev_tx_msg *)buf; 640 msg->begin = USB_8DEV_DATA_START; 641 msg->flags = 0x00; 642 643 if (cf->can_id & CAN_RTR_FLAG) 644 msg->flags |= USB_8DEV_RTR; 645 646 if (cf->can_id & CAN_EFF_FLAG) 647 msg->flags |= USB_8DEV_EXTID; 648 649 msg->id = cpu_to_be32(cf->can_id & CAN_ERR_MASK); 650 msg->dlc = cf->can_dlc; 651 memcpy(msg->data, cf->data, cf->can_dlc); 652 msg->end = USB_8DEV_DATA_END; 653 654 for (i = 0; i < MAX_TX_URBS; i++) { 655 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) { 656 context = &priv->tx_contexts[i]; 657 break; 658 } 659 } 660 661 /* May never happen! When this happens we'd more URBs in flight as 662 * allowed (MAX_TX_URBS). 663 */ 664 if (!context) 665 goto nofreecontext; 666 667 context->priv = priv; 668 context->echo_index = i; 669 context->dlc = cf->can_dlc; 670 671 usb_fill_bulk_urb(urb, priv->udev, 672 usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_TX), 673 buf, size, usb_8dev_write_bulk_callback, context); 674 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 675 usb_anchor_urb(urb, &priv->tx_submitted); 676 677 can_put_echo_skb(skb, netdev, context->echo_index); 678 679 atomic_inc(&priv->active_tx_urbs); 680 681 err = usb_submit_urb(urb, GFP_ATOMIC); 682 if (unlikely(err)) 683 goto failed; 684 else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS) 685 /* Slow down tx path */ 686 netif_stop_queue(netdev); 687 688 /* Release our reference to this URB, the USB core will eventually free 689 * it entirely. 690 */ 691 usb_free_urb(urb); 692 693 return NETDEV_TX_OK; 694 695nofreecontext: 696 usb_unanchor_urb(urb); 697 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma); 698 699 netdev_warn(netdev, "couldn't find free context"); 700 701 return NETDEV_TX_BUSY; 702 703failed: 704 can_free_echo_skb(netdev, context->echo_index); 705 706 usb_unanchor_urb(urb); 707 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma); 708 709 atomic_dec(&priv->active_tx_urbs); 710 711 if (err == -ENODEV) 712 netif_device_detach(netdev); 713 else 714 netdev_warn(netdev, "failed tx_urb %d\n", err); 715 716nomembuf: 717 usb_free_urb(urb); 718 719nomem: 720 dev_kfree_skb(skb); 721 stats->tx_dropped++; 722 723 return NETDEV_TX_OK; 724} 725 726static int usb_8dev_get_berr_counter(const struct net_device *netdev, 727 struct can_berr_counter *bec) 728{ 729 struct usb_8dev_priv *priv = netdev_priv(netdev); 730 731 bec->txerr = priv->bec.txerr; 732 bec->rxerr = priv->bec.rxerr; 733 734 return 0; 735} 736 737/* Start USB device */ 738static int usb_8dev_start(struct usb_8dev_priv *priv) 739{ 740 struct net_device *netdev = priv->netdev; 741 int err, i; 742 743 for (i = 0; i < MAX_RX_URBS; i++) { 744 struct urb *urb = NULL; 745 u8 *buf; 746 747 /* create a URB, and a buffer for it */ 748 urb = usb_alloc_urb(0, GFP_KERNEL); 749 if (!urb) { 750 netdev_err(netdev, "No memory left for URBs\n"); 751 err = -ENOMEM; 752 break; 753 } 754 755 buf = usb_alloc_coherent(priv->udev, RX_BUFFER_SIZE, GFP_KERNEL, 756 &urb->transfer_dma); 757 if (!buf) { 758 netdev_err(netdev, "No memory left for USB buffer\n"); 759 usb_free_urb(urb); 760 err = -ENOMEM; 761 break; 762 } 763 764 usb_fill_bulk_urb(urb, priv->udev, 765 usb_rcvbulkpipe(priv->udev, 766 USB_8DEV_ENDP_DATA_RX), 767 buf, RX_BUFFER_SIZE, 768 usb_8dev_read_bulk_callback, priv); 769 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 770 usb_anchor_urb(urb, &priv->rx_submitted); 771 772 err = usb_submit_urb(urb, GFP_KERNEL); 773 if (err) { 774 usb_unanchor_urb(urb); 775 usb_free_coherent(priv->udev, RX_BUFFER_SIZE, buf, 776 urb->transfer_dma); 777 break; 778 } 779 780 /* Drop reference, USB core will take care of freeing it */ 781 usb_free_urb(urb); 782 } 783 784 /* Did we submit any URBs */ 785 if (i == 0) { 786 netdev_warn(netdev, "couldn't setup read URBs\n"); 787 return err; 788 } 789 790 /* Warn if we've couldn't transmit all the URBs */ 791 if (i < MAX_RX_URBS) 792 netdev_warn(netdev, "rx performance may be slow\n"); 793 794 err = usb_8dev_cmd_open(priv); 795 if (err) 796 goto failed; 797 798 priv->can.state = CAN_STATE_ERROR_ACTIVE; 799 800 return 0; 801 802failed: 803 if (err == -ENODEV) 804 netif_device_detach(priv->netdev); 805 806 netdev_warn(netdev, "couldn't submit control: %d\n", err); 807 808 return err; 809} 810 811/* Open USB device */ 812static int usb_8dev_open(struct net_device *netdev) 813{ 814 struct usb_8dev_priv *priv = netdev_priv(netdev); 815 int err; 816 817 /* common open */ 818 err = open_candev(netdev); 819 if (err) 820 return err; 821 822 /* finally start device */ 823 err = usb_8dev_start(priv); 824 if (err) { 825 if (err == -ENODEV) 826 netif_device_detach(priv->netdev); 827 828 netdev_warn(netdev, "couldn't start device: %d\n", 829 err); 830 831 close_candev(netdev); 832 833 return err; 834 } 835 836 netif_start_queue(netdev); 837 838 return 0; 839} 840 841static void unlink_all_urbs(struct usb_8dev_priv *priv) 842{ 843 int i; 844 845 usb_kill_anchored_urbs(&priv->rx_submitted); 846 847 usb_kill_anchored_urbs(&priv->tx_submitted); 848 atomic_set(&priv->active_tx_urbs, 0); 849 850 for (i = 0; i < MAX_TX_URBS; i++) 851 priv->tx_contexts[i].echo_index = MAX_TX_URBS; 852} 853 854/* Close USB device */ 855static int usb_8dev_close(struct net_device *netdev) 856{ 857 struct usb_8dev_priv *priv = netdev_priv(netdev); 858 int err = 0; 859 860 /* Send CLOSE command to CAN controller */ 861 err = usb_8dev_cmd_close(priv); 862 if (err) 863 netdev_warn(netdev, "couldn't stop device"); 864 865 priv->can.state = CAN_STATE_STOPPED; 866 867 netif_stop_queue(netdev); 868 869 /* Stop polling */ 870 unlink_all_urbs(priv); 871 872 close_candev(netdev); 873 874 return err; 875} 876 877static const struct net_device_ops usb_8dev_netdev_ops = { 878 .ndo_open = usb_8dev_open, 879 .ndo_stop = usb_8dev_close, 880 .ndo_start_xmit = usb_8dev_start_xmit, 881}; 882 883static const struct can_bittiming_const usb_8dev_bittiming_const = { 884 .name = "usb_8dev", 885 .tseg1_min = 1, 886 .tseg1_max = 16, 887 .tseg2_min = 1, 888 .tseg2_max = 8, 889 .sjw_max = 4, 890 .brp_min = 1, 891 .brp_max = 1024, 892 .brp_inc = 1, 893}; 894 895/* Probe USB device 896 * 897 * Check device and firmware. 898 * Set supported modes and bittiming constants. 899 * Allocate some memory. 900 */ 901static int usb_8dev_probe(struct usb_interface *intf, 902 const struct usb_device_id *id) 903{ 904 struct net_device *netdev; 905 struct usb_8dev_priv *priv; 906 int i, err = -ENOMEM; 907 u32 version; 908 char buf[18]; 909 struct usb_device *usbdev = interface_to_usbdev(intf); 910 911 /* product id looks strange, better we also check iProduct string */ 912 if (usb_string(usbdev, usbdev->descriptor.iProduct, buf, 913 sizeof(buf)) > 0 && strcmp(buf, "USB2CAN converter")) { 914 dev_info(&usbdev->dev, "ignoring: not an USB2CAN converter\n"); 915 return -ENODEV; 916 } 917 918 netdev = alloc_candev(sizeof(struct usb_8dev_priv), MAX_TX_URBS); 919 if (!netdev) { 920 dev_err(&intf->dev, "Couldn't alloc candev\n"); 921 return -ENOMEM; 922 } 923 924 priv = netdev_priv(netdev); 925 926 priv->udev = usbdev; 927 priv->netdev = netdev; 928 929 priv->can.state = CAN_STATE_STOPPED; 930 priv->can.clock.freq = USB_8DEV_ABP_CLOCK; 931 priv->can.bittiming_const = &usb_8dev_bittiming_const; 932 priv->can.do_set_mode = usb_8dev_set_mode; 933 priv->can.do_get_berr_counter = usb_8dev_get_berr_counter; 934 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | 935 CAN_CTRLMODE_LISTENONLY | 936 CAN_CTRLMODE_ONE_SHOT; 937 938 netdev->netdev_ops = &usb_8dev_netdev_ops; 939 940 netdev->flags |= IFF_ECHO; /* we support local echo */ 941 942 init_usb_anchor(&priv->rx_submitted); 943 944 init_usb_anchor(&priv->tx_submitted); 945 atomic_set(&priv->active_tx_urbs, 0); 946 947 for (i = 0; i < MAX_TX_URBS; i++) 948 priv->tx_contexts[i].echo_index = MAX_TX_URBS; 949 950 priv->cmd_msg_buffer = kzalloc(sizeof(struct usb_8dev_cmd_msg), 951 GFP_KERNEL); 952 if (!priv->cmd_msg_buffer) { 953 netdev_err(netdev, "Couldn't alloc Tx buffer\n"); 954 goto cleanup_candev; 955 } 956 957 usb_set_intfdata(intf, priv); 958 959 SET_NETDEV_DEV(netdev, &intf->dev); 960 961 mutex_init(&priv->usb_8dev_cmd_lock); 962 963 err = register_candev(netdev); 964 if (err) { 965 netdev_err(netdev, 966 "couldn't register CAN device: %d\n", err); 967 goto cleanup_cmd_msg_buffer; 968 } 969 970 err = usb_8dev_cmd_version(priv, &version); 971 if (err) { 972 netdev_err(netdev, "can't get firmware version\n"); 973 goto cleanup_cmd_msg_buffer; 974 } else { 975 netdev_info(netdev, 976 "firmware: %d.%d, hardware: %d.%d\n", 977 (version>>24) & 0xff, (version>>16) & 0xff, 978 (version>>8) & 0xff, version & 0xff); 979 } 980 981 return 0; 982 983cleanup_cmd_msg_buffer: 984 kfree(priv->cmd_msg_buffer); 985 986cleanup_candev: 987 free_candev(netdev); 988 989 return err; 990 991} 992 993/* Called by the usb core when driver is unloaded or device is removed */ 994static void usb_8dev_disconnect(struct usb_interface *intf) 995{ 996 struct usb_8dev_priv *priv = usb_get_intfdata(intf); 997 998 usb_set_intfdata(intf, NULL); 999 1000 if (priv) { 1001 netdev_info(priv->netdev, "device disconnected\n"); 1002 1003 unregister_netdev(priv->netdev); 1004 free_candev(priv->netdev); 1005 1006 unlink_all_urbs(priv); 1007 } 1008 1009} 1010 1011static struct usb_driver usb_8dev_driver = { 1012 .name = "usb_8dev", 1013 .probe = usb_8dev_probe, 1014 .disconnect = usb_8dev_disconnect, 1015 .id_table = usb_8dev_table, 1016}; 1017 1018module_usb_driver(usb_8dev_driver); 1019 1020MODULE_AUTHOR("Bernd Krumboeck <krumboeck@universalnet.at>"); 1021MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces"); 1022MODULE_LICENSE("GPL v2"); 1023