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v4.17
   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 */
  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		priv->can.can_stats.bus_off++;
 381		can_bus_off(priv->netdev);
 382		break;
 383	case USB_8DEV_STATUSMSG_OVERRUN:
 384	case USB_8DEV_STATUSMSG_BUSLIGHT:
 385	case USB_8DEV_STATUSMSG_BUSHEAVY:
 386		cf->can_id |= CAN_ERR_CRTL;
 387		break;
 388	default:
 389		priv->can.state = CAN_STATE_ERROR_WARNING;
 390		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 391		priv->can.can_stats.bus_error++;
 392		break;
 393	}
 394
 395	switch (state) {
 396	case USB_8DEV_STATUSMSG_OK:
 397	case USB_8DEV_STATUSMSG_BUSOFF:
 398		break;
 399	case USB_8DEV_STATUSMSG_ACK:
 400		cf->can_id |= CAN_ERR_ACK;
 401		tx_errors = 1;
 402		break;
 403	case USB_8DEV_STATUSMSG_CRC:
 404		cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
 
 
 405		rx_errors = 1;
 406		break;
 407	case USB_8DEV_STATUSMSG_BIT0:
 408		cf->data[2] |= CAN_ERR_PROT_BIT0;
 409		tx_errors = 1;
 410		break;
 411	case USB_8DEV_STATUSMSG_BIT1:
 412		cf->data[2] |= CAN_ERR_PROT_BIT1;
 413		tx_errors = 1;
 414		break;
 415	case USB_8DEV_STATUSMSG_FORM:
 416		cf->data[2] |= CAN_ERR_PROT_FORM;
 417		rx_errors = 1;
 418		break;
 419	case USB_8DEV_STATUSMSG_STUFF:
 420		cf->data[2] |= CAN_ERR_PROT_STUFF;
 421		rx_errors = 1;
 422		break;
 423	case USB_8DEV_STATUSMSG_OVERRUN:
 424		cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
 425		stats->rx_over_errors++;
 426		rx_errors = 1;
 427		break;
 428	case USB_8DEV_STATUSMSG_BUSLIGHT:
 429		priv->can.state = CAN_STATE_ERROR_WARNING;
 430		cf->data[1] = (txerr > rxerr) ?
 431			CAN_ERR_CRTL_TX_WARNING :
 432			CAN_ERR_CRTL_RX_WARNING;
 433		priv->can.can_stats.error_warning++;
 434		break;
 435	case USB_8DEV_STATUSMSG_BUSHEAVY:
 436		priv->can.state = CAN_STATE_ERROR_PASSIVE;
 437		cf->data[1] = (txerr > rxerr) ?
 438			CAN_ERR_CRTL_TX_PASSIVE :
 439			CAN_ERR_CRTL_RX_PASSIVE;
 440		priv->can.can_stats.error_passive++;
 441		break;
 442	default:
 443		netdev_warn(priv->netdev,
 444			    "Unknown status/error message (%d)\n", state);
 445		break;
 446	}
 447
 448	if (tx_errors) {
 449		cf->data[2] |= CAN_ERR_PROT_TX;
 450		stats->tx_errors++;
 451	}
 452
 453	if (rx_errors)
 454		stats->rx_errors++;
 455
 456	cf->data[6] = txerr;
 457	cf->data[7] = rxerr;
 458
 459	priv->bec.txerr = txerr;
 460	priv->bec.rxerr = rxerr;
 461
 
 
 462	stats->rx_packets++;
 463	stats->rx_bytes += cf->can_dlc;
 464	netif_rx(skb);
 465}
 466
 467/* Read data and status frames */
 468static void usb_8dev_rx_can_msg(struct usb_8dev_priv *priv,
 469				struct usb_8dev_rx_msg *msg)
 470{
 471	struct can_frame *cf;
 472	struct sk_buff *skb;
 473	struct net_device_stats *stats = &priv->netdev->stats;
 474
 475	if (msg->type == USB_8DEV_TYPE_ERROR_FRAME &&
 476		   msg->flags == USB_8DEV_ERR_FLAG) {
 477		usb_8dev_rx_err_msg(priv, msg);
 478	} else if (msg->type == USB_8DEV_TYPE_CAN_FRAME) {
 479		skb = alloc_can_skb(priv->netdev, &cf);
 480		if (!skb)
 481			return;
 482
 483		cf->can_id = be32_to_cpu(msg->id);
 484		cf->can_dlc = get_can_dlc(msg->dlc & 0xF);
 485
 486		if (msg->flags & USB_8DEV_EXTID)
 487			cf->can_id |= CAN_EFF_FLAG;
 488
 489		if (msg->flags & USB_8DEV_RTR)
 490			cf->can_id |= CAN_RTR_FLAG;
 491		else
 492			memcpy(cf->data, msg->data, cf->can_dlc);
 493
 
 
 494		stats->rx_packets++;
 495		stats->rx_bytes += cf->can_dlc;
 496		netif_rx(skb);
 497
 498		can_led_event(priv->netdev, CAN_LED_EVENT_RX);
 499	} else {
 500		netdev_warn(priv->netdev, "frame type %d unknown",
 501			 msg->type);
 502	}
 503
 504}
 505
 506/* Callback for reading data from device
 507 *
 508 * Check urb status, call read function and resubmit urb read operation.
 509 */
 510static void usb_8dev_read_bulk_callback(struct urb *urb)
 511{
 512	struct usb_8dev_priv *priv = urb->context;
 513	struct net_device *netdev;
 514	int retval;
 515	int pos = 0;
 516
 517	netdev = priv->netdev;
 518
 519	if (!netif_device_present(netdev))
 520		return;
 521
 522	switch (urb->status) {
 523	case 0: /* success */
 524		break;
 525
 526	case -ENOENT:
 527	case -EPIPE:
 528	case -EPROTO:
 529	case -ESHUTDOWN:
 530		return;
 531
 532	default:
 533		netdev_info(netdev, "Rx URB aborted (%d)\n",
 534			 urb->status);
 535		goto resubmit_urb;
 536	}
 537
 538	while (pos < urb->actual_length) {
 539		struct usb_8dev_rx_msg *msg;
 540
 541		if (pos + sizeof(struct usb_8dev_rx_msg) > urb->actual_length) {
 542			netdev_err(priv->netdev, "format error\n");
 543			break;
 544		}
 545
 546		msg = (struct usb_8dev_rx_msg *)(urb->transfer_buffer + pos);
 547		usb_8dev_rx_can_msg(priv, msg);
 548
 549		pos += sizeof(struct usb_8dev_rx_msg);
 550	}
 551
 552resubmit_urb:
 553	usb_fill_bulk_urb(urb, priv->udev,
 554			  usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_RX),
 555			  urb->transfer_buffer, RX_BUFFER_SIZE,
 556			  usb_8dev_read_bulk_callback, priv);
 557
 558	retval = usb_submit_urb(urb, GFP_ATOMIC);
 559
 560	if (retval == -ENODEV)
 561		netif_device_detach(netdev);
 562	else if (retval)
 563		netdev_err(netdev,
 564			"failed resubmitting read bulk urb: %d\n", retval);
 565}
 566
 567/* Callback handler for write operations
 568 *
 569 * Free allocated buffers, check transmit status and
 570 * calculate statistic.
 571 */
 572static void usb_8dev_write_bulk_callback(struct urb *urb)
 573{
 574	struct usb_8dev_tx_urb_context *context = urb->context;
 575	struct usb_8dev_priv *priv;
 576	struct net_device *netdev;
 577
 578	BUG_ON(!context);
 579
 580	priv = context->priv;
 581	netdev = priv->netdev;
 582
 583	/* free up our allocated buffer */
 584	usb_free_coherent(urb->dev, urb->transfer_buffer_length,
 585			  urb->transfer_buffer, urb->transfer_dma);
 586
 587	atomic_dec(&priv->active_tx_urbs);
 588
 589	if (!netif_device_present(netdev))
 590		return;
 591
 592	if (urb->status)
 593		netdev_info(netdev, "Tx URB aborted (%d)\n",
 594			 urb->status);
 595
 596	netdev->stats.tx_packets++;
 597	netdev->stats.tx_bytes += context->dlc;
 598
 599	can_get_echo_skb(netdev, context->echo_index);
 600
 601	can_led_event(netdev, CAN_LED_EVENT_TX);
 602
 603	/* Release context */
 604	context->echo_index = MAX_TX_URBS;
 605
 606	netif_wake_queue(netdev);
 607}
 608
 609/* Send data to device */
 610static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb,
 611				      struct net_device *netdev)
 612{
 613	struct usb_8dev_priv *priv = netdev_priv(netdev);
 614	struct net_device_stats *stats = &netdev->stats;
 615	struct can_frame *cf = (struct can_frame *) skb->data;
 616	struct usb_8dev_tx_msg *msg;
 617	struct urb *urb;
 618	struct usb_8dev_tx_urb_context *context = NULL;
 619	u8 *buf;
 620	int i, err;
 621	size_t size = sizeof(struct usb_8dev_tx_msg);
 622
 623	if (can_dropped_invalid_skb(netdev, skb))
 624		return NETDEV_TX_OK;
 625
 626	/* create a URB, and a buffer for it, and copy the data to the URB */
 627	urb = usb_alloc_urb(0, GFP_ATOMIC);
 628	if (!urb)
 
 629		goto nomem;
 
 630
 631	buf = usb_alloc_coherent(priv->udev, size, GFP_ATOMIC,
 632				 &urb->transfer_dma);
 633	if (!buf) {
 634		netdev_err(netdev, "No memory left for USB buffer\n");
 635		goto nomembuf;
 636	}
 637
 638	memset(buf, 0, size);
 639
 640	msg = (struct usb_8dev_tx_msg *)buf;
 641	msg->begin = USB_8DEV_DATA_START;
 642	msg->flags = 0x00;
 643
 644	if (cf->can_id & CAN_RTR_FLAG)
 645		msg->flags |= USB_8DEV_RTR;
 646
 647	if (cf->can_id & CAN_EFF_FLAG)
 648		msg->flags |= USB_8DEV_EXTID;
 649
 650	msg->id = cpu_to_be32(cf->can_id & CAN_ERR_MASK);
 651	msg->dlc = cf->can_dlc;
 652	memcpy(msg->data, cf->data, cf->can_dlc);
 653	msg->end = USB_8DEV_DATA_END;
 654
 655	for (i = 0; i < MAX_TX_URBS; i++) {
 656		if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
 657			context = &priv->tx_contexts[i];
 658			break;
 659		}
 660	}
 661
 662	/* May never happen! When this happens we'd more URBs in flight as
 663	 * allowed (MAX_TX_URBS).
 664	 */
 665	if (!context)
 666		goto nofreecontext;
 667
 668	context->priv = priv;
 669	context->echo_index = i;
 670	context->dlc = cf->can_dlc;
 671
 672	usb_fill_bulk_urb(urb, priv->udev,
 673			  usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_TX),
 674			  buf, size, usb_8dev_write_bulk_callback, context);
 675	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 676	usb_anchor_urb(urb, &priv->tx_submitted);
 677
 678	can_put_echo_skb(skb, netdev, context->echo_index);
 679
 680	atomic_inc(&priv->active_tx_urbs);
 681
 682	err = usb_submit_urb(urb, GFP_ATOMIC);
 683	if (unlikely(err))
 684		goto failed;
 685	else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS)
 686		/* Slow down tx path */
 687		netif_stop_queue(netdev);
 688
 689	/* Release our reference to this URB, the USB core will eventually free
 690	 * it entirely.
 691	 */
 692	usb_free_urb(urb);
 693
 694	return NETDEV_TX_OK;
 695
 696nofreecontext:
 697	usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
 698	usb_free_urb(urb);
 699
 700	netdev_warn(netdev, "couldn't find free context");
 701
 702	return NETDEV_TX_BUSY;
 703
 704failed:
 705	can_free_echo_skb(netdev, context->echo_index);
 706
 707	usb_unanchor_urb(urb);
 708	usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
 709
 710	atomic_dec(&priv->active_tx_urbs);
 711
 712	if (err == -ENODEV)
 713		netif_device_detach(netdev);
 714	else
 715		netdev_warn(netdev, "failed tx_urb %d\n", err);
 716
 717nomembuf:
 718	usb_free_urb(urb);
 719
 720nomem:
 721	dev_kfree_skb(skb);
 722	stats->tx_dropped++;
 723
 724	return NETDEV_TX_OK;
 725}
 726
 727static int usb_8dev_get_berr_counter(const struct net_device *netdev,
 728				     struct can_berr_counter *bec)
 729{
 730	struct usb_8dev_priv *priv = netdev_priv(netdev);
 731
 732	bec->txerr = priv->bec.txerr;
 733	bec->rxerr = priv->bec.rxerr;
 734
 735	return 0;
 736}
 737
 738/* Start USB device */
 739static int usb_8dev_start(struct usb_8dev_priv *priv)
 740{
 741	struct net_device *netdev = priv->netdev;
 742	int err, i;
 743
 744	for (i = 0; i < MAX_RX_URBS; i++) {
 745		struct urb *urb = NULL;
 746		u8 *buf;
 747
 748		/* create a URB, and a buffer for it */
 749		urb = usb_alloc_urb(0, GFP_KERNEL);
 750		if (!urb) {
 
 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			usb_free_urb(urb);
 778			break;
 779		}
 780
 781		/* Drop reference, USB core will take care of freeing it */
 782		usb_free_urb(urb);
 783	}
 784
 785	/* Did we submit any URBs */
 786	if (i == 0) {
 787		netdev_warn(netdev, "couldn't setup read URBs\n");
 788		return err;
 789	}
 790
 791	/* Warn if we've couldn't transmit all the URBs */
 792	if (i < MAX_RX_URBS)
 793		netdev_warn(netdev, "rx performance may be slow\n");
 794
 795	err = usb_8dev_cmd_open(priv);
 796	if (err)
 797		goto failed;
 798
 799	priv->can.state = CAN_STATE_ERROR_ACTIVE;
 800
 801	return 0;
 802
 803failed:
 804	if (err == -ENODEV)
 805		netif_device_detach(priv->netdev);
 806
 807	netdev_warn(netdev, "couldn't submit control: %d\n", err);
 808
 809	return err;
 810}
 811
 812/* Open USB device */
 813static int usb_8dev_open(struct net_device *netdev)
 814{
 815	struct usb_8dev_priv *priv = netdev_priv(netdev);
 816	int err;
 817
 818	/* common open */
 819	err = open_candev(netdev);
 820	if (err)
 821		return err;
 822
 823	can_led_event(netdev, CAN_LED_EVENT_OPEN);
 824
 825	/* finally start device */
 826	err = usb_8dev_start(priv);
 827	if (err) {
 828		if (err == -ENODEV)
 829			netif_device_detach(priv->netdev);
 830
 831		netdev_warn(netdev, "couldn't start device: %d\n",
 832			 err);
 833
 834		close_candev(netdev);
 835
 836		return err;
 837	}
 838
 839	netif_start_queue(netdev);
 840
 841	return 0;
 842}
 843
 844static void unlink_all_urbs(struct usb_8dev_priv *priv)
 845{
 846	int i;
 847
 848	usb_kill_anchored_urbs(&priv->rx_submitted);
 849
 850	usb_kill_anchored_urbs(&priv->tx_submitted);
 851	atomic_set(&priv->active_tx_urbs, 0);
 852
 853	for (i = 0; i < MAX_TX_URBS; i++)
 854		priv->tx_contexts[i].echo_index = MAX_TX_URBS;
 855}
 856
 857/* Close USB device */
 858static int usb_8dev_close(struct net_device *netdev)
 859{
 860	struct usb_8dev_priv *priv = netdev_priv(netdev);
 861	int err = 0;
 862
 863	/* Send CLOSE command to CAN controller */
 864	err = usb_8dev_cmd_close(priv);
 865	if (err)
 866		netdev_warn(netdev, "couldn't stop device");
 867
 868	priv->can.state = CAN_STATE_STOPPED;
 869
 870	netif_stop_queue(netdev);
 871
 872	/* Stop polling */
 873	unlink_all_urbs(priv);
 874
 875	close_candev(netdev);
 876
 877	can_led_event(netdev, CAN_LED_EVENT_STOP);
 878
 879	return err;
 880}
 881
 882static const struct net_device_ops usb_8dev_netdev_ops = {
 883	.ndo_open = usb_8dev_open,
 884	.ndo_stop = usb_8dev_close,
 885	.ndo_start_xmit = usb_8dev_start_xmit,
 886	.ndo_change_mtu = can_change_mtu,
 887};
 888
 889static const struct can_bittiming_const usb_8dev_bittiming_const = {
 890	.name = "usb_8dev",
 891	.tseg1_min = 1,
 892	.tseg1_max = 16,
 893	.tseg2_min = 1,
 894	.tseg2_max = 8,
 895	.sjw_max = 4,
 896	.brp_min = 1,
 897	.brp_max = 1024,
 898	.brp_inc = 1,
 899};
 900
 901/* Probe USB device
 902 *
 903 * Check device and firmware.
 904 * Set supported modes and bittiming constants.
 905 * Allocate some memory.
 906 */
 907static int usb_8dev_probe(struct usb_interface *intf,
 908			 const struct usb_device_id *id)
 909{
 910	struct net_device *netdev;
 911	struct usb_8dev_priv *priv;
 912	int i, err = -ENOMEM;
 913	u32 version;
 914	char buf[18];
 915	struct usb_device *usbdev = interface_to_usbdev(intf);
 916
 917	/* product id looks strange, better we also check iProduct string */
 918	if (usb_string(usbdev, usbdev->descriptor.iProduct, buf,
 919		       sizeof(buf)) > 0 && strcmp(buf, "USB2CAN converter")) {
 920		dev_info(&usbdev->dev, "ignoring: not an USB2CAN converter\n");
 921		return -ENODEV;
 922	}
 923
 924	netdev = alloc_candev(sizeof(struct usb_8dev_priv), MAX_TX_URBS);
 925	if (!netdev) {
 926		dev_err(&intf->dev, "Couldn't alloc candev\n");
 927		return -ENOMEM;
 928	}
 929
 930	priv = netdev_priv(netdev);
 931
 932	priv->udev = usbdev;
 933	priv->netdev = netdev;
 934
 935	priv->can.state = CAN_STATE_STOPPED;
 936	priv->can.clock.freq = USB_8DEV_ABP_CLOCK;
 937	priv->can.bittiming_const = &usb_8dev_bittiming_const;
 938	priv->can.do_set_mode = usb_8dev_set_mode;
 939	priv->can.do_get_berr_counter = usb_8dev_get_berr_counter;
 940	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
 941				      CAN_CTRLMODE_LISTENONLY |
 942				      CAN_CTRLMODE_ONE_SHOT;
 943
 944	netdev->netdev_ops = &usb_8dev_netdev_ops;
 945
 946	netdev->flags |= IFF_ECHO; /* we support local echo */
 947
 948	init_usb_anchor(&priv->rx_submitted);
 949
 950	init_usb_anchor(&priv->tx_submitted);
 951	atomic_set(&priv->active_tx_urbs, 0);
 952
 953	for (i = 0; i < MAX_TX_URBS; i++)
 954		priv->tx_contexts[i].echo_index = MAX_TX_URBS;
 955
 956	priv->cmd_msg_buffer = devm_kzalloc(&intf->dev, sizeof(struct usb_8dev_cmd_msg),
 957					    GFP_KERNEL);
 958	if (!priv->cmd_msg_buffer)
 959		goto cleanup_candev;
 960
 961	usb_set_intfdata(intf, priv);
 962
 963	SET_NETDEV_DEV(netdev, &intf->dev);
 964
 965	mutex_init(&priv->usb_8dev_cmd_lock);
 966
 967	err = register_candev(netdev);
 968	if (err) {
 969		netdev_err(netdev,
 970			"couldn't register CAN device: %d\n", err);
 971		goto cleanup_candev;
 972	}
 973
 974	err = usb_8dev_cmd_version(priv, &version);
 975	if (err) {
 976		netdev_err(netdev, "can't get firmware version\n");
 977		goto cleanup_unregister_candev;
 978	} else {
 979		netdev_info(netdev,
 980			 "firmware: %d.%d, hardware: %d.%d\n",
 981			 (version>>24) & 0xff, (version>>16) & 0xff,
 982			 (version>>8) & 0xff, version & 0xff);
 983	}
 984
 985	devm_can_led_init(netdev);
 986
 987	return 0;
 988
 989cleanup_unregister_candev:
 990	unregister_netdev(priv->netdev);
 
 
 
 991
 992cleanup_candev:
 993	free_candev(netdev);
 994
 995	return err;
 996
 997}
 998
 999/* Called by the usb core when driver is unloaded or device is removed */
1000static void usb_8dev_disconnect(struct usb_interface *intf)
1001{
1002	struct usb_8dev_priv *priv = usb_get_intfdata(intf);
1003
1004	usb_set_intfdata(intf, NULL);
1005
1006	if (priv) {
1007		netdev_info(priv->netdev, "device disconnected\n");
1008
1009		unregister_netdev(priv->netdev);
1010		free_candev(priv->netdev);
1011
1012		unlink_all_urbs(priv);
1013	}
1014
1015}
1016
1017static struct usb_driver usb_8dev_driver = {
1018	.name =		"usb_8dev",
1019	.probe =	usb_8dev_probe,
1020	.disconnect =	usb_8dev_disconnect,
1021	.id_table =	usb_8dev_table,
1022};
1023
1024module_usb_driver(usb_8dev_driver);
1025
1026MODULE_AUTHOR("Bernd Krumboeck <krumboeck@universalnet.at>");
1027MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces");
1028MODULE_LICENSE("GPL v2");
v3.15
   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 */
  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
 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 */
 513static 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
 553resubmit_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 */
 573static 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 */
 611static 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
 699nofreecontext:
 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
 707failed:
 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
 720nomembuf:
 721	usb_free_urb(urb);
 722
 723nomem:
 724	dev_kfree_skb(skb);
 725	stats->tx_dropped++;
 726
 727	return NETDEV_TX_OK;
 728}
 729
 730static 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 */
 742static 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
 807failed:
 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 */
 817static 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
 848static 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 */
 862static 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
 886static 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
 893static 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 */
 911static 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
 993cleanup_unregister_candev:
 994	unregister_netdev(priv->netdev);
 995
 996cleanup_cmd_msg_buffer:
 997	kfree(priv->cmd_msg_buffer);
 998
 999cleanup_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 */
1007static 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
1024static 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
1031module_usb_driver(usb_8dev_driver);
1032
1033MODULE_AUTHOR("Bernd Krumboeck <krumboeck@universalnet.at>");
1034MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces");
1035MODULE_LICENSE("GPL v2");