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/signal.h> 27 #include <linux/slab.h> 28 #include <linux/module.h> 29 #include <linux/netdevice.h> 30 #include <linux/usb.h> 31 32 #include <linux/can.h> 33 #include <linux/can/dev.h> 34 #include <linux/can/error.h> 35 #include <linux/can/led.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 */ 47 enum 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 */ 64 enum 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 */ 117 static const struct usb_device_id usb_8dev_table[] = { 118 { USB_DEVICE(USB_8DEV_VENDOR_ID, USB_8DEV_PRODUCT_ID) }, 119 { } /* Terminating entry */ 120 }; 121 122 MODULE_DEVICE_TABLE(usb, usb_8dev_table); 123 124 struct 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 */ 132 struct 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 */ 155 struct __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 */ 165 struct __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 */ 177 struct __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 }; 186 187 static 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 } 195 196 static 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 */ 207 static 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; 245 246 failed: 247 mutex_unlock(&priv->usb_8dev_cmd_lock); 248 return err; 249 } 250 251 /* Send open command to device */ 252 static 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 */ 288 static 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 */ 302 static 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 */ 326 static 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 */ 346 static 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 */ 470 static 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; 500 501 can_led_event(priv->netdev, CAN_LED_EVENT_RX); 502 } else { 503 netdev_warn(priv->netdev, "frame type %d unknown", 504 msg->type); 505 } 506 507 } 508 509 /* Callback for reading data from device 510 * 511 * Check urb status, call read function and resubmit urb read operation. 512 */ 513 static void usb_8dev_read_bulk_callback(struct urb *urb) 514 { 515 struct usb_8dev_priv *priv = urb->context; 516 struct net_device *netdev; 517 int retval; 518 int pos = 0; 519 520 netdev = priv->netdev; 521 522 if (!netif_device_present(netdev)) 523 return; 524 525 switch (urb->status) { 526 case 0: /* success */ 527 break; 528 529 case -ENOENT: 530 case -ESHUTDOWN: 531 return; 532 533 default: 534 netdev_info(netdev, "Rx URB aborted (%d)\n", 535 urb->status); 536 goto resubmit_urb; 537 } 538 539 while (pos < urb->actual_length) { 540 struct usb_8dev_rx_msg *msg; 541 542 if (pos + sizeof(struct usb_8dev_rx_msg) > urb->actual_length) { 543 netdev_err(priv->netdev, "format error\n"); 544 break; 545 } 546 547 msg = (struct usb_8dev_rx_msg *)(urb->transfer_buffer + pos); 548 usb_8dev_rx_can_msg(priv, msg); 549 550 pos += sizeof(struct usb_8dev_rx_msg); 551 } 552 553 resubmit_urb: 554 usb_fill_bulk_urb(urb, priv->udev, 555 usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_RX), 556 urb->transfer_buffer, RX_BUFFER_SIZE, 557 usb_8dev_read_bulk_callback, priv); 558 559 retval = usb_submit_urb(urb, GFP_ATOMIC); 560 561 if (retval == -ENODEV) 562 netif_device_detach(netdev); 563 else if (retval) 564 netdev_err(netdev, 565 "failed resubmitting read bulk urb: %d\n", retval); 566 } 567 568 /* Callback handler for write operations 569 * 570 * Free allocated buffers, check transmit status and 571 * calculate statistic. 572 */ 573 static void usb_8dev_write_bulk_callback(struct urb *urb) 574 { 575 struct usb_8dev_tx_urb_context *context = urb->context; 576 struct usb_8dev_priv *priv; 577 struct net_device *netdev; 578 579 BUG_ON(!context); 580 581 priv = context->priv; 582 netdev = priv->netdev; 583 584 /* free up our allocated buffer */ 585 usb_free_coherent(urb->dev, urb->transfer_buffer_length, 586 urb->transfer_buffer, urb->transfer_dma); 587 588 atomic_dec(&priv->active_tx_urbs); 589 590 if (!netif_device_present(netdev)) 591 return; 592 593 if (urb->status) 594 netdev_info(netdev, "Tx URB aborted (%d)\n", 595 urb->status); 596 597 netdev->stats.tx_packets++; 598 netdev->stats.tx_bytes += context->dlc; 599 600 can_get_echo_skb(netdev, context->echo_index); 601 602 can_led_event(netdev, CAN_LED_EVENT_TX); 603 604 /* Release context */ 605 context->echo_index = MAX_TX_URBS; 606 607 netif_wake_queue(netdev); 608 } 609 610 /* Send data to device */ 611 static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb, 612 struct net_device *netdev) 613 { 614 struct usb_8dev_priv *priv = netdev_priv(netdev); 615 struct net_device_stats *stats = &netdev->stats; 616 struct can_frame *cf = (struct can_frame *) skb->data; 617 struct usb_8dev_tx_msg *msg; 618 struct urb *urb; 619 struct usb_8dev_tx_urb_context *context = NULL; 620 u8 *buf; 621 int i, err; 622 size_t size = sizeof(struct usb_8dev_tx_msg); 623 624 if (can_dropped_invalid_skb(netdev, skb)) 625 return NETDEV_TX_OK; 626 627 /* create a URB, and a buffer for it, and copy the data to the URB */ 628 urb = usb_alloc_urb(0, GFP_ATOMIC); 629 if (!urb) { 630 netdev_err(netdev, "No memory left for URBs\n"); 631 goto nomem; 632 } 633 634 buf = usb_alloc_coherent(priv->udev, size, GFP_ATOMIC, 635 &urb->transfer_dma); 636 if (!buf) { 637 netdev_err(netdev, "No memory left for USB buffer\n"); 638 goto nomembuf; 639 } 640 641 memset(buf, 0, size); 642 643 msg = (struct usb_8dev_tx_msg *)buf; 644 msg->begin = USB_8DEV_DATA_START; 645 msg->flags = 0x00; 646 647 if (cf->can_id & CAN_RTR_FLAG) 648 msg->flags |= USB_8DEV_RTR; 649 650 if (cf->can_id & CAN_EFF_FLAG) 651 msg->flags |= USB_8DEV_EXTID; 652 653 msg->id = cpu_to_be32(cf->can_id & CAN_ERR_MASK); 654 msg->dlc = cf->can_dlc; 655 memcpy(msg->data, cf->data, cf->can_dlc); 656 msg->end = USB_8DEV_DATA_END; 657 658 for (i = 0; i < MAX_TX_URBS; i++) { 659 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) { 660 context = &priv->tx_contexts[i]; 661 break; 662 } 663 } 664 665 /* May never happen! When this happens we'd more URBs in flight as 666 * allowed (MAX_TX_URBS). 667 */ 668 if (!context) 669 goto nofreecontext; 670 671 context->priv = priv; 672 context->echo_index = i; 673 context->dlc = cf->can_dlc; 674 675 usb_fill_bulk_urb(urb, priv->udev, 676 usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_TX), 677 buf, size, usb_8dev_write_bulk_callback, context); 678 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 679 usb_anchor_urb(urb, &priv->tx_submitted); 680 681 can_put_echo_skb(skb, netdev, context->echo_index); 682 683 atomic_inc(&priv->active_tx_urbs); 684 685 err = usb_submit_urb(urb, GFP_ATOMIC); 686 if (unlikely(err)) 687 goto failed; 688 else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS) 689 /* Slow down tx path */ 690 netif_stop_queue(netdev); 691 692 /* Release our reference to this URB, the USB core will eventually free 693 * it entirely. 694 */ 695 usb_free_urb(urb); 696 697 return NETDEV_TX_OK; 698 699 nofreecontext: 700 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma); 701 usb_free_urb(urb); 702 703 netdev_warn(netdev, "couldn't find free context"); 704 705 return NETDEV_TX_BUSY; 706 707 failed: 708 can_free_echo_skb(netdev, context->echo_index); 709 710 usb_unanchor_urb(urb); 711 usb_free_coherent(priv->udev, size, buf, urb->transfer_dma); 712 713 atomic_dec(&priv->active_tx_urbs); 714 715 if (err == -ENODEV) 716 netif_device_detach(netdev); 717 else 718 netdev_warn(netdev, "failed tx_urb %d\n", err); 719 720 nomembuf: 721 usb_free_urb(urb); 722 723 nomem: 724 dev_kfree_skb(skb); 725 stats->tx_dropped++; 726 727 return NETDEV_TX_OK; 728 } 729 730 static int usb_8dev_get_berr_counter(const struct net_device *netdev, 731 struct can_berr_counter *bec) 732 { 733 struct usb_8dev_priv *priv = netdev_priv(netdev); 734 735 bec->txerr = priv->bec.txerr; 736 bec->rxerr = priv->bec.rxerr; 737 738 return 0; 739 } 740 741 /* Start USB device */ 742 static int usb_8dev_start(struct usb_8dev_priv *priv) 743 { 744 struct net_device *netdev = priv->netdev; 745 int err, i; 746 747 for (i = 0; i < MAX_RX_URBS; i++) { 748 struct urb *urb = NULL; 749 u8 *buf; 750 751 /* create a URB, and a buffer for it */ 752 urb = usb_alloc_urb(0, GFP_KERNEL); 753 if (!urb) { 754 netdev_err(netdev, "No memory left for URBs\n"); 755 err = -ENOMEM; 756 break; 757 } 758 759 buf = usb_alloc_coherent(priv->udev, RX_BUFFER_SIZE, GFP_KERNEL, 760 &urb->transfer_dma); 761 if (!buf) { 762 netdev_err(netdev, "No memory left for USB buffer\n"); 763 usb_free_urb(urb); 764 err = -ENOMEM; 765 break; 766 } 767 768 usb_fill_bulk_urb(urb, priv->udev, 769 usb_rcvbulkpipe(priv->udev, 770 USB_8DEV_ENDP_DATA_RX), 771 buf, RX_BUFFER_SIZE, 772 usb_8dev_read_bulk_callback, priv); 773 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 774 usb_anchor_urb(urb, &priv->rx_submitted); 775 776 err = usb_submit_urb(urb, GFP_KERNEL); 777 if (err) { 778 usb_unanchor_urb(urb); 779 usb_free_coherent(priv->udev, RX_BUFFER_SIZE, buf, 780 urb->transfer_dma); 781 usb_free_urb(urb); 782 break; 783 } 784 785 /* Drop reference, USB core will take care of freeing it */ 786 usb_free_urb(urb); 787 } 788 789 /* Did we submit any URBs */ 790 if (i == 0) { 791 netdev_warn(netdev, "couldn't setup read URBs\n"); 792 return err; 793 } 794 795 /* Warn if we've couldn't transmit all the URBs */ 796 if (i < MAX_RX_URBS) 797 netdev_warn(netdev, "rx performance may be slow\n"); 798 799 err = usb_8dev_cmd_open(priv); 800 if (err) 801 goto failed; 802 803 priv->can.state = CAN_STATE_ERROR_ACTIVE; 804 805 return 0; 806 807 failed: 808 if (err == -ENODEV) 809 netif_device_detach(priv->netdev); 810 811 netdev_warn(netdev, "couldn't submit control: %d\n", err); 812 813 return err; 814 } 815 816 /* Open USB device */ 817 static int usb_8dev_open(struct net_device *netdev) 818 { 819 struct usb_8dev_priv *priv = netdev_priv(netdev); 820 int err; 821 822 /* common open */ 823 err = open_candev(netdev); 824 if (err) 825 return err; 826 827 can_led_event(netdev, CAN_LED_EVENT_OPEN); 828 829 /* finally start device */ 830 err = usb_8dev_start(priv); 831 if (err) { 832 if (err == -ENODEV) 833 netif_device_detach(priv->netdev); 834 835 netdev_warn(netdev, "couldn't start device: %d\n", 836 err); 837 838 close_candev(netdev); 839 840 return err; 841 } 842 843 netif_start_queue(netdev); 844 845 return 0; 846 } 847 848 static void unlink_all_urbs(struct usb_8dev_priv *priv) 849 { 850 int i; 851 852 usb_kill_anchored_urbs(&priv->rx_submitted); 853 854 usb_kill_anchored_urbs(&priv->tx_submitted); 855 atomic_set(&priv->active_tx_urbs, 0); 856 857 for (i = 0; i < MAX_TX_URBS; i++) 858 priv->tx_contexts[i].echo_index = MAX_TX_URBS; 859 } 860 861 /* Close USB device */ 862 static int usb_8dev_close(struct net_device *netdev) 863 { 864 struct usb_8dev_priv *priv = netdev_priv(netdev); 865 int err = 0; 866 867 /* Send CLOSE command to CAN controller */ 868 err = usb_8dev_cmd_close(priv); 869 if (err) 870 netdev_warn(netdev, "couldn't stop device"); 871 872 priv->can.state = CAN_STATE_STOPPED; 873 874 netif_stop_queue(netdev); 875 876 /* Stop polling */ 877 unlink_all_urbs(priv); 878 879 close_candev(netdev); 880 881 can_led_event(netdev, CAN_LED_EVENT_STOP); 882 883 return err; 884 } 885 886 static const struct net_device_ops usb_8dev_netdev_ops = { 887 .ndo_open = usb_8dev_open, 888 .ndo_stop = usb_8dev_close, 889 .ndo_start_xmit = usb_8dev_start_xmit, 890 .ndo_change_mtu = can_change_mtu, 891 }; 892 893 static const struct can_bittiming_const usb_8dev_bittiming_const = { 894 .name = "usb_8dev", 895 .tseg1_min = 1, 896 .tseg1_max = 16, 897 .tseg2_min = 1, 898 .tseg2_max = 8, 899 .sjw_max = 4, 900 .brp_min = 1, 901 .brp_max = 1024, 902 .brp_inc = 1, 903 }; 904 905 /* Probe USB device 906 * 907 * Check device and firmware. 908 * Set supported modes and bittiming constants. 909 * Allocate some memory. 910 */ 911 static int usb_8dev_probe(struct usb_interface *intf, 912 const struct usb_device_id *id) 913 { 914 struct net_device *netdev; 915 struct usb_8dev_priv *priv; 916 int i, err = -ENOMEM; 917 u32 version; 918 char buf[18]; 919 struct usb_device *usbdev = interface_to_usbdev(intf); 920 921 /* product id looks strange, better we also check iProduct string */ 922 if (usb_string(usbdev, usbdev->descriptor.iProduct, buf, 923 sizeof(buf)) > 0 && strcmp(buf, "USB2CAN converter")) { 924 dev_info(&usbdev->dev, "ignoring: not an USB2CAN converter\n"); 925 return -ENODEV; 926 } 927 928 netdev = alloc_candev(sizeof(struct usb_8dev_priv), MAX_TX_URBS); 929 if (!netdev) { 930 dev_err(&intf->dev, "Couldn't alloc candev\n"); 931 return -ENOMEM; 932 } 933 934 priv = netdev_priv(netdev); 935 936 priv->udev = usbdev; 937 priv->netdev = netdev; 938 939 priv->can.state = CAN_STATE_STOPPED; 940 priv->can.clock.freq = USB_8DEV_ABP_CLOCK; 941 priv->can.bittiming_const = &usb_8dev_bittiming_const; 942 priv->can.do_set_mode = usb_8dev_set_mode; 943 priv->can.do_get_berr_counter = usb_8dev_get_berr_counter; 944 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | 945 CAN_CTRLMODE_LISTENONLY | 946 CAN_CTRLMODE_ONE_SHOT; 947 948 netdev->netdev_ops = &usb_8dev_netdev_ops; 949 950 netdev->flags |= IFF_ECHO; /* we support local echo */ 951 952 init_usb_anchor(&priv->rx_submitted); 953 954 init_usb_anchor(&priv->tx_submitted); 955 atomic_set(&priv->active_tx_urbs, 0); 956 957 for (i = 0; i < MAX_TX_URBS; i++) 958 priv->tx_contexts[i].echo_index = MAX_TX_URBS; 959 960 priv->cmd_msg_buffer = kzalloc(sizeof(struct usb_8dev_cmd_msg), 961 GFP_KERNEL); 962 if (!priv->cmd_msg_buffer) 963 goto cleanup_candev; 964 965 usb_set_intfdata(intf, priv); 966 967 SET_NETDEV_DEV(netdev, &intf->dev); 968 969 mutex_init(&priv->usb_8dev_cmd_lock); 970 971 err = register_candev(netdev); 972 if (err) { 973 netdev_err(netdev, 974 "couldn't register CAN device: %d\n", err); 975 goto cleanup_cmd_msg_buffer; 976 } 977 978 err = usb_8dev_cmd_version(priv, &version); 979 if (err) { 980 netdev_err(netdev, "can't get firmware version\n"); 981 goto cleanup_unregister_candev; 982 } else { 983 netdev_info(netdev, 984 "firmware: %d.%d, hardware: %d.%d\n", 985 (version>>24) & 0xff, (version>>16) & 0xff, 986 (version>>8) & 0xff, version & 0xff); 987 } 988 989 devm_can_led_init(netdev); 990 991 return 0; 992 993 cleanup_unregister_candev: 994 unregister_netdev(priv->netdev); 995 996 cleanup_cmd_msg_buffer: 997 kfree(priv->cmd_msg_buffer); 998 999 cleanup_candev: 1000 free_candev(netdev); 1001 1002 return err; 1003 1004 } 1005 1006 /* Called by the usb core when driver is unloaded or device is removed */ 1007 static void usb_8dev_disconnect(struct usb_interface *intf) 1008 { 1009 struct usb_8dev_priv *priv = usb_get_intfdata(intf); 1010 1011 usb_set_intfdata(intf, NULL); 1012 1013 if (priv) { 1014 netdev_info(priv->netdev, "device disconnected\n"); 1015 1016 unregister_netdev(priv->netdev); 1017 free_candev(priv->netdev); 1018 1019 unlink_all_urbs(priv); 1020 } 1021 1022 } 1023 1024 static struct usb_driver usb_8dev_driver = { 1025 .name = "usb_8dev", 1026 .probe = usb_8dev_probe, 1027 .disconnect = usb_8dev_disconnect, 1028 .id_table = usb_8dev_table, 1029 }; 1030 1031 module_usb_driver(usb_8dev_driver); 1032 1033 MODULE_AUTHOR("Bernd Krumboeck <krumboeck@universalnet.at>"); 1034 MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces"); 1035 MODULE_LICENSE("GPL v2"); 1036