Linux Audio

Check our new training course

Loading...
Note: File does not exist in v6.8.
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * CAN driver for esd CAN-USB/2 and CAN-USB/Micro
   4 *
   5 * Copyright (C) 2010-2012 Matthias Fuchs <matthias.fuchs@esd.eu>, esd gmbh
   6 */
   7#include <linux/signal.h>
   8#include <linux/slab.h>
   9#include <linux/module.h>
  10#include <linux/netdevice.h>
  11#include <linux/usb.h>
  12
  13#include <linux/can.h>
  14#include <linux/can/dev.h>
  15#include <linux/can/error.h>
  16
  17MODULE_AUTHOR("Matthias Fuchs <matthias.fuchs@esd.eu>");
  18MODULE_DESCRIPTION("CAN driver for esd CAN-USB/2 and CAN-USB/Micro interfaces");
  19MODULE_LICENSE("GPL v2");
  20
  21/* Define these values to match your devices */
  22#define USB_ESDGMBH_VENDOR_ID	0x0ab4
  23#define USB_CANUSB2_PRODUCT_ID	0x0010
  24#define USB_CANUSBM_PRODUCT_ID	0x0011
  25
  26#define ESD_USB2_CAN_CLOCK	60000000
  27#define ESD_USBM_CAN_CLOCK	36000000
  28#define ESD_USB2_MAX_NETS	2
  29
  30/* USB2 commands */
  31#define CMD_VERSION		1 /* also used for VERSION_REPLY */
  32#define CMD_CAN_RX		2 /* device to host only */
  33#define CMD_CAN_TX		3 /* also used for TX_DONE */
  34#define CMD_SETBAUD		4 /* also used for SETBAUD_REPLY */
  35#define CMD_TS			5 /* also used for TS_REPLY */
  36#define CMD_IDADD		6 /* also used for IDADD_REPLY */
  37
  38/* esd CAN message flags - dlc field */
  39#define ESD_RTR			0x10
  40
  41/* esd CAN message flags - id field */
  42#define ESD_EXTID		0x20000000
  43#define ESD_EVENT		0x40000000
  44#define ESD_IDMASK		0x1fffffff
  45
  46/* esd CAN event ids used by this driver */
  47#define ESD_EV_CAN_ERROR_EXT	2
  48
  49/* baudrate message flags */
  50#define ESD_USB2_UBR		0x80000000
  51#define ESD_USB2_LOM		0x40000000
  52#define ESD_USB2_NO_BAUDRATE	0x7fffffff
  53#define ESD_USB2_TSEG1_MIN	1
  54#define ESD_USB2_TSEG1_MAX	16
  55#define ESD_USB2_TSEG1_SHIFT	16
  56#define ESD_USB2_TSEG2_MIN	1
  57#define ESD_USB2_TSEG2_MAX	8
  58#define ESD_USB2_TSEG2_SHIFT	20
  59#define ESD_USB2_SJW_MAX	4
  60#define ESD_USB2_SJW_SHIFT	14
  61#define ESD_USBM_SJW_SHIFT	24
  62#define ESD_USB2_BRP_MIN	1
  63#define ESD_USB2_BRP_MAX	1024
  64#define ESD_USB2_BRP_INC	1
  65#define ESD_USB2_3_SAMPLES	0x00800000
  66
  67/* esd IDADD message */
  68#define ESD_ID_ENABLE		0x80
  69#define ESD_MAX_ID_SEGMENT	64
  70
  71/* SJA1000 ECC register (emulated by usb2 firmware) */
  72#define SJA1000_ECC_SEG		0x1F
  73#define SJA1000_ECC_DIR		0x20
  74#define SJA1000_ECC_ERR		0x06
  75#define SJA1000_ECC_BIT		0x00
  76#define SJA1000_ECC_FORM	0x40
  77#define SJA1000_ECC_STUFF	0x80
  78#define SJA1000_ECC_MASK	0xc0
  79
  80/* esd bus state event codes */
  81#define ESD_BUSSTATE_MASK	0xc0
  82#define ESD_BUSSTATE_WARN	0x40
  83#define ESD_BUSSTATE_ERRPASSIVE	0x80
  84#define ESD_BUSSTATE_BUSOFF	0xc0
  85
  86#define RX_BUFFER_SIZE		1024
  87#define MAX_RX_URBS		4
  88#define MAX_TX_URBS		16 /* must be power of 2 */
  89
  90struct header_msg {
  91	u8 len; /* len is always the total message length in 32bit words */
  92	u8 cmd;
  93	u8 rsvd[2];
  94};
  95
  96struct version_msg {
  97	u8 len;
  98	u8 cmd;
  99	u8 rsvd;
 100	u8 flags;
 101	__le32 drv_version;
 102};
 103
 104struct version_reply_msg {
 105	u8 len;
 106	u8 cmd;
 107	u8 nets;
 108	u8 features;
 109	__le32 version;
 110	u8 name[16];
 111	__le32 rsvd;
 112	__le32 ts;
 113};
 114
 115struct rx_msg {
 116	u8 len;
 117	u8 cmd;
 118	u8 net;
 119	u8 dlc;
 120	__le32 ts;
 121	__le32 id; /* upper 3 bits contain flags */
 122	u8 data[8];
 123};
 124
 125struct tx_msg {
 126	u8 len;
 127	u8 cmd;
 128	u8 net;
 129	u8 dlc;
 130	u32 hnd;	/* opaque handle, not used by device */
 131	__le32 id; /* upper 3 bits contain flags */
 132	u8 data[8];
 133};
 134
 135struct tx_done_msg {
 136	u8 len;
 137	u8 cmd;
 138	u8 net;
 139	u8 status;
 140	u32 hnd;	/* opaque handle, not used by device */
 141	__le32 ts;
 142};
 143
 144struct id_filter_msg {
 145	u8 len;
 146	u8 cmd;
 147	u8 net;
 148	u8 option;
 149	__le32 mask[ESD_MAX_ID_SEGMENT + 1];
 150};
 151
 152struct set_baudrate_msg {
 153	u8 len;
 154	u8 cmd;
 155	u8 net;
 156	u8 rsvd;
 157	__le32 baud;
 158};
 159
 160/* Main message type used between library and application */
 161struct __attribute__ ((packed)) esd_usb2_msg {
 162	union {
 163		struct header_msg hdr;
 164		struct version_msg version;
 165		struct version_reply_msg version_reply;
 166		struct rx_msg rx;
 167		struct tx_msg tx;
 168		struct tx_done_msg txdone;
 169		struct set_baudrate_msg setbaud;
 170		struct id_filter_msg filter;
 171	} msg;
 172};
 173
 174static struct usb_device_id esd_usb2_table[] = {
 175	{USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSB2_PRODUCT_ID)},
 176	{USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSBM_PRODUCT_ID)},
 177	{}
 178};
 179MODULE_DEVICE_TABLE(usb, esd_usb2_table);
 180
 181struct esd_usb2_net_priv;
 182
 183struct esd_tx_urb_context {
 184	struct esd_usb2_net_priv *priv;
 185	u32 echo_index;
 186	int dlc;
 187};
 188
 189struct esd_usb2 {
 190	struct usb_device *udev;
 191	struct esd_usb2_net_priv *nets[ESD_USB2_MAX_NETS];
 192
 193	struct usb_anchor rx_submitted;
 194
 195	int net_count;
 196	u32 version;
 197	int rxinitdone;
 198};
 199
 200struct esd_usb2_net_priv {
 201	struct can_priv can; /* must be the first member */
 202
 203	atomic_t active_tx_jobs;
 204	struct usb_anchor tx_submitted;
 205	struct esd_tx_urb_context tx_contexts[MAX_TX_URBS];
 206
 207	struct esd_usb2 *usb2;
 208	struct net_device *netdev;
 209	int index;
 210	u8 old_state;
 211	struct can_berr_counter bec;
 212};
 213
 214static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
 215			      struct esd_usb2_msg *msg)
 216{
 217	struct net_device_stats *stats = &priv->netdev->stats;
 218	struct can_frame *cf;
 219	struct sk_buff *skb;
 220	u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
 221
 222	if (id == ESD_EV_CAN_ERROR_EXT) {
 223		u8 state = msg->msg.rx.data[0];
 224		u8 ecc = msg->msg.rx.data[1];
 225		u8 txerr = msg->msg.rx.data[2];
 226		u8 rxerr = msg->msg.rx.data[3];
 227
 228		skb = alloc_can_err_skb(priv->netdev, &cf);
 229		if (skb == NULL) {
 230			stats->rx_dropped++;
 231			return;
 232		}
 233
 234		if (state != priv->old_state) {
 235			priv->old_state = state;
 236
 237			switch (state & ESD_BUSSTATE_MASK) {
 238			case ESD_BUSSTATE_BUSOFF:
 239				priv->can.state = CAN_STATE_BUS_OFF;
 240				cf->can_id |= CAN_ERR_BUSOFF;
 241				priv->can.can_stats.bus_off++;
 242				can_bus_off(priv->netdev);
 243				break;
 244			case ESD_BUSSTATE_WARN:
 245				priv->can.state = CAN_STATE_ERROR_WARNING;
 246				priv->can.can_stats.error_warning++;
 247				break;
 248			case ESD_BUSSTATE_ERRPASSIVE:
 249				priv->can.state = CAN_STATE_ERROR_PASSIVE;
 250				priv->can.can_stats.error_passive++;
 251				break;
 252			default:
 253				priv->can.state = CAN_STATE_ERROR_ACTIVE;
 254				break;
 255			}
 256		} else {
 257			priv->can.can_stats.bus_error++;
 258			stats->rx_errors++;
 259
 260			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 261
 262			switch (ecc & SJA1000_ECC_MASK) {
 263			case SJA1000_ECC_BIT:
 264				cf->data[2] |= CAN_ERR_PROT_BIT;
 265				break;
 266			case SJA1000_ECC_FORM:
 267				cf->data[2] |= CAN_ERR_PROT_FORM;
 268				break;
 269			case SJA1000_ECC_STUFF:
 270				cf->data[2] |= CAN_ERR_PROT_STUFF;
 271				break;
 272			default:
 273				cf->data[3] = ecc & SJA1000_ECC_SEG;
 274				break;
 275			}
 276
 277			/* Error occurred during transmission? */
 278			if (!(ecc & SJA1000_ECC_DIR))
 279				cf->data[2] |= CAN_ERR_PROT_TX;
 280
 281			if (priv->can.state == CAN_STATE_ERROR_WARNING ||
 282			    priv->can.state == CAN_STATE_ERROR_PASSIVE) {
 283				cf->data[1] = (txerr > rxerr) ?
 284					CAN_ERR_CRTL_TX_PASSIVE :
 285					CAN_ERR_CRTL_RX_PASSIVE;
 286			}
 287			cf->data[6] = txerr;
 288			cf->data[7] = rxerr;
 289		}
 290
 291		priv->bec.txerr = txerr;
 292		priv->bec.rxerr = rxerr;
 293
 294		stats->rx_packets++;
 295		stats->rx_bytes += cf->can_dlc;
 296		netif_rx(skb);
 297	}
 298}
 299
 300static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv,
 301				struct esd_usb2_msg *msg)
 302{
 303	struct net_device_stats *stats = &priv->netdev->stats;
 304	struct can_frame *cf;
 305	struct sk_buff *skb;
 306	int i;
 307	u32 id;
 308
 309	if (!netif_device_present(priv->netdev))
 310		return;
 311
 312	id = le32_to_cpu(msg->msg.rx.id);
 313
 314	if (id & ESD_EVENT) {
 315		esd_usb2_rx_event(priv, msg);
 316	} else {
 317		skb = alloc_can_skb(priv->netdev, &cf);
 318		if (skb == NULL) {
 319			stats->rx_dropped++;
 320			return;
 321		}
 322
 323		cf->can_id = id & ESD_IDMASK;
 324		cf->can_dlc = get_can_dlc(msg->msg.rx.dlc & ~ESD_RTR);
 325
 326		if (id & ESD_EXTID)
 327			cf->can_id |= CAN_EFF_FLAG;
 328
 329		if (msg->msg.rx.dlc & ESD_RTR) {
 330			cf->can_id |= CAN_RTR_FLAG;
 331		} else {
 332			for (i = 0; i < cf->can_dlc; i++)
 333				cf->data[i] = msg->msg.rx.data[i];
 334		}
 335
 336		stats->rx_packets++;
 337		stats->rx_bytes += cf->can_dlc;
 338		netif_rx(skb);
 339	}
 340
 341	return;
 342}
 343
 344static void esd_usb2_tx_done_msg(struct esd_usb2_net_priv *priv,
 345				 struct esd_usb2_msg *msg)
 346{
 347	struct net_device_stats *stats = &priv->netdev->stats;
 348	struct net_device *netdev = priv->netdev;
 349	struct esd_tx_urb_context *context;
 350
 351	if (!netif_device_present(netdev))
 352		return;
 353
 354	context = &priv->tx_contexts[msg->msg.txdone.hnd & (MAX_TX_URBS - 1)];
 355
 356	if (!msg->msg.txdone.status) {
 357		stats->tx_packets++;
 358		stats->tx_bytes += context->dlc;
 359		can_get_echo_skb(netdev, context->echo_index);
 360	} else {
 361		stats->tx_errors++;
 362		can_free_echo_skb(netdev, context->echo_index);
 363	}
 364
 365	/* Release context */
 366	context->echo_index = MAX_TX_URBS;
 367	atomic_dec(&priv->active_tx_jobs);
 368
 369	netif_wake_queue(netdev);
 370}
 371
 372static void esd_usb2_read_bulk_callback(struct urb *urb)
 373{
 374	struct esd_usb2 *dev = urb->context;
 375	int retval;
 376	int pos = 0;
 377	int i;
 378
 379	switch (urb->status) {
 380	case 0: /* success */
 381		break;
 382
 383	case -ENOENT:
 384	case -EPIPE:
 385	case -EPROTO:
 386	case -ESHUTDOWN:
 387		return;
 388
 389	default:
 390		dev_info(dev->udev->dev.parent,
 391			 "Rx URB aborted (%d)\n", urb->status);
 392		goto resubmit_urb;
 393	}
 394
 395	while (pos < urb->actual_length) {
 396		struct esd_usb2_msg *msg;
 397
 398		msg = (struct esd_usb2_msg *)(urb->transfer_buffer + pos);
 399
 400		switch (msg->msg.hdr.cmd) {
 401		case CMD_CAN_RX:
 402			if (msg->msg.rx.net >= dev->net_count) {
 403				dev_err(dev->udev->dev.parent, "format error\n");
 404				break;
 405			}
 406
 407			esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
 408			break;
 409
 410		case CMD_CAN_TX:
 411			if (msg->msg.txdone.net >= dev->net_count) {
 412				dev_err(dev->udev->dev.parent, "format error\n");
 413				break;
 414			}
 415
 416			esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
 417					     msg);
 418			break;
 419		}
 420
 421		pos += msg->msg.hdr.len << 2;
 422
 423		if (pos > urb->actual_length) {
 424			dev_err(dev->udev->dev.parent, "format error\n");
 425			break;
 426		}
 427	}
 428
 429resubmit_urb:
 430	usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
 431			  urb->transfer_buffer, RX_BUFFER_SIZE,
 432			  esd_usb2_read_bulk_callback, dev);
 433
 434	retval = usb_submit_urb(urb, GFP_ATOMIC);
 435	if (retval == -ENODEV) {
 436		for (i = 0; i < dev->net_count; i++) {
 437			if (dev->nets[i])
 438				netif_device_detach(dev->nets[i]->netdev);
 439		}
 440	} else if (retval) {
 441		dev_err(dev->udev->dev.parent,
 442			"failed resubmitting read bulk urb: %d\n", retval);
 443	}
 444
 445	return;
 446}
 447
 448/*
 449 * callback for bulk IN urb
 450 */
 451static void esd_usb2_write_bulk_callback(struct urb *urb)
 452{
 453	struct esd_tx_urb_context *context = urb->context;
 454	struct esd_usb2_net_priv *priv;
 455	struct net_device *netdev;
 456	size_t size = sizeof(struct esd_usb2_msg);
 457
 458	WARN_ON(!context);
 459
 460	priv = context->priv;
 461	netdev = priv->netdev;
 462
 463	/* free up our allocated buffer */
 464	usb_free_coherent(urb->dev, size,
 465			  urb->transfer_buffer, urb->transfer_dma);
 466
 467	if (!netif_device_present(netdev))
 468		return;
 469
 470	if (urb->status)
 471		netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
 472
 473	netif_trans_update(netdev);
 474}
 475
 476static ssize_t show_firmware(struct device *d,
 477			     struct device_attribute *attr, char *buf)
 478{
 479	struct usb_interface *intf = to_usb_interface(d);
 480	struct esd_usb2 *dev = usb_get_intfdata(intf);
 481
 482	return sprintf(buf, "%d.%d.%d\n",
 483		       (dev->version >> 12) & 0xf,
 484		       (dev->version >> 8) & 0xf,
 485		       dev->version & 0xff);
 486}
 487static DEVICE_ATTR(firmware, 0444, show_firmware, NULL);
 488
 489static ssize_t show_hardware(struct device *d,
 490			     struct device_attribute *attr, char *buf)
 491{
 492	struct usb_interface *intf = to_usb_interface(d);
 493	struct esd_usb2 *dev = usb_get_intfdata(intf);
 494
 495	return sprintf(buf, "%d.%d.%d\n",
 496		       (dev->version >> 28) & 0xf,
 497		       (dev->version >> 24) & 0xf,
 498		       (dev->version >> 16) & 0xff);
 499}
 500static DEVICE_ATTR(hardware, 0444, show_hardware, NULL);
 501
 502static ssize_t show_nets(struct device *d,
 503			 struct device_attribute *attr, char *buf)
 504{
 505	struct usb_interface *intf = to_usb_interface(d);
 506	struct esd_usb2 *dev = usb_get_intfdata(intf);
 507
 508	return sprintf(buf, "%d", dev->net_count);
 509}
 510static DEVICE_ATTR(nets, 0444, show_nets, NULL);
 511
 512static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)
 513{
 514	int actual_length;
 515
 516	return usb_bulk_msg(dev->udev,
 517			    usb_sndbulkpipe(dev->udev, 2),
 518			    msg,
 519			    msg->msg.hdr.len << 2,
 520			    &actual_length,
 521			    1000);
 522}
 523
 524static int esd_usb2_wait_msg(struct esd_usb2 *dev,
 525			     struct esd_usb2_msg *msg)
 526{
 527	int actual_length;
 528
 529	return usb_bulk_msg(dev->udev,
 530			    usb_rcvbulkpipe(dev->udev, 1),
 531			    msg,
 532			    sizeof(*msg),
 533			    &actual_length,
 534			    1000);
 535}
 536
 537static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
 538{
 539	int i, err = 0;
 540
 541	if (dev->rxinitdone)
 542		return 0;
 543
 544	for (i = 0; i < MAX_RX_URBS; i++) {
 545		struct urb *urb = NULL;
 546		u8 *buf = NULL;
 547
 548		/* create a URB, and a buffer for it */
 549		urb = usb_alloc_urb(0, GFP_KERNEL);
 550		if (!urb) {
 551			err = -ENOMEM;
 552			break;
 553		}
 554
 555		buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
 556					 &urb->transfer_dma);
 557		if (!buf) {
 558			dev_warn(dev->udev->dev.parent,
 559				 "No memory left for USB buffer\n");
 560			err = -ENOMEM;
 561			goto freeurb;
 562		}
 563
 564		usb_fill_bulk_urb(urb, dev->udev,
 565				  usb_rcvbulkpipe(dev->udev, 1),
 566				  buf, RX_BUFFER_SIZE,
 567				  esd_usb2_read_bulk_callback, dev);
 568		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 569		usb_anchor_urb(urb, &dev->rx_submitted);
 570
 571		err = usb_submit_urb(urb, GFP_KERNEL);
 572		if (err) {
 573			usb_unanchor_urb(urb);
 574			usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
 575					  urb->transfer_dma);
 576		}
 577
 578freeurb:
 579		/* Drop reference, USB core will take care of freeing it */
 580		usb_free_urb(urb);
 581		if (err)
 582			break;
 583	}
 584
 585	/* Did we submit any URBs */
 586	if (i == 0) {
 587		dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
 588		return err;
 589	}
 590
 591	/* Warn if we've couldn't transmit all the URBs */
 592	if (i < MAX_RX_URBS) {
 593		dev_warn(dev->udev->dev.parent,
 594			 "rx performance may be slow\n");
 595	}
 596
 597	dev->rxinitdone = 1;
 598	return 0;
 599}
 600
 601/*
 602 * Start interface
 603 */
 604static int esd_usb2_start(struct esd_usb2_net_priv *priv)
 605{
 606	struct esd_usb2 *dev = priv->usb2;
 607	struct net_device *netdev = priv->netdev;
 608	struct esd_usb2_msg *msg;
 609	int err, i;
 610
 611	msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 612	if (!msg) {
 613		err = -ENOMEM;
 614		goto out;
 615	}
 616
 617	/*
 618	 * Enable all IDs
 619	 * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
 620	 * Each bit represents one 11 bit CAN identifier. A set bit
 621	 * enables reception of the corresponding CAN identifier. A cleared
 622	 * bit disabled this identifier. An additional bitmask value
 623	 * following the CAN 2.0A bits is used to enable reception of
 624	 * extended CAN frames. Only the LSB of this final mask is checked
 625	 * for the complete 29 bit ID range. The IDADD message also allows
 626	 * filter configuration for an ID subset. In this case you can add
 627	 * the number of the starting bitmask (0..64) to the filter.option
 628	 * field followed by only some bitmasks.
 629	 */
 630	msg->msg.hdr.cmd = CMD_IDADD;
 631	msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 632	msg->msg.filter.net = priv->index;
 633	msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 634	for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
 635		msg->msg.filter.mask[i] = cpu_to_le32(0xffffffff);
 636	/* enable 29bit extended IDs */
 637	msg->msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
 638
 639	err = esd_usb2_send_msg(dev, msg);
 640	if (err)
 641		goto out;
 642
 643	err = esd_usb2_setup_rx_urbs(dev);
 644	if (err)
 645		goto out;
 646
 647	priv->can.state = CAN_STATE_ERROR_ACTIVE;
 648
 649out:
 650	if (err == -ENODEV)
 651		netif_device_detach(netdev);
 652	if (err)
 653		netdev_err(netdev, "couldn't start device: %d\n", err);
 654
 655	kfree(msg);
 656	return err;
 657}
 658
 659static void unlink_all_urbs(struct esd_usb2 *dev)
 660{
 661	struct esd_usb2_net_priv *priv;
 662	int i, j;
 663
 664	usb_kill_anchored_urbs(&dev->rx_submitted);
 665	for (i = 0; i < dev->net_count; i++) {
 666		priv = dev->nets[i];
 667		if (priv) {
 668			usb_kill_anchored_urbs(&priv->tx_submitted);
 669			atomic_set(&priv->active_tx_jobs, 0);
 670
 671			for (j = 0; j < MAX_TX_URBS; j++)
 672				priv->tx_contexts[j].echo_index = MAX_TX_URBS;
 673		}
 674	}
 675}
 676
 677static int esd_usb2_open(struct net_device *netdev)
 678{
 679	struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 680	int err;
 681
 682	/* common open */
 683	err = open_candev(netdev);
 684	if (err)
 685		return err;
 686
 687	/* finally start device */
 688	err = esd_usb2_start(priv);
 689	if (err) {
 690		netdev_warn(netdev, "couldn't start device: %d\n", err);
 691		close_candev(netdev);
 692		return err;
 693	}
 694
 695	netif_start_queue(netdev);
 696
 697	return 0;
 698}
 699
 700static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
 701				      struct net_device *netdev)
 702{
 703	struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 704	struct esd_usb2 *dev = priv->usb2;
 705	struct esd_tx_urb_context *context = NULL;
 706	struct net_device_stats *stats = &netdev->stats;
 707	struct can_frame *cf = (struct can_frame *)skb->data;
 708	struct esd_usb2_msg *msg;
 709	struct urb *urb;
 710	u8 *buf;
 711	int i, err;
 712	int ret = NETDEV_TX_OK;
 713	size_t size = sizeof(struct esd_usb2_msg);
 714
 715	if (can_dropped_invalid_skb(netdev, skb))
 716		return NETDEV_TX_OK;
 717
 718	/* create a URB, and a buffer for it, and copy the data to the URB */
 719	urb = usb_alloc_urb(0, GFP_ATOMIC);
 720	if (!urb) {
 721		stats->tx_dropped++;
 722		dev_kfree_skb(skb);
 723		goto nourbmem;
 724	}
 725
 726	buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
 727				 &urb->transfer_dma);
 728	if (!buf) {
 729		netdev_err(netdev, "No memory left for USB buffer\n");
 730		stats->tx_dropped++;
 731		dev_kfree_skb(skb);
 732		goto nobufmem;
 733	}
 734
 735	msg = (struct esd_usb2_msg *)buf;
 736
 737	msg->msg.hdr.len = 3; /* minimal length */
 738	msg->msg.hdr.cmd = CMD_CAN_TX;
 739	msg->msg.tx.net = priv->index;
 740	msg->msg.tx.dlc = cf->can_dlc;
 741	msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
 742
 743	if (cf->can_id & CAN_RTR_FLAG)
 744		msg->msg.tx.dlc |= ESD_RTR;
 745
 746	if (cf->can_id & CAN_EFF_FLAG)
 747		msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
 748
 749	for (i = 0; i < cf->can_dlc; i++)
 750		msg->msg.tx.data[i] = cf->data[i];
 751
 752	msg->msg.hdr.len += (cf->can_dlc + 3) >> 2;
 753
 754	for (i = 0; i < MAX_TX_URBS; i++) {
 755		if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
 756			context = &priv->tx_contexts[i];
 757			break;
 758		}
 759	}
 760
 761	/*
 762	 * This may never happen.
 763	 */
 764	if (!context) {
 765		netdev_warn(netdev, "couldn't find free context\n");
 766		ret = NETDEV_TX_BUSY;
 767		goto releasebuf;
 768	}
 769
 770	context->priv = priv;
 771	context->echo_index = i;
 772	context->dlc = cf->can_dlc;
 773
 774	/* hnd must not be 0 - MSB is stripped in txdone handling */
 775	msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
 776
 777	usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
 778			  msg->msg.hdr.len << 2,
 779			  esd_usb2_write_bulk_callback, context);
 780
 781	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 782
 783	usb_anchor_urb(urb, &priv->tx_submitted);
 784
 785	can_put_echo_skb(skb, netdev, context->echo_index);
 786
 787	atomic_inc(&priv->active_tx_jobs);
 788
 789	/* Slow down tx path */
 790	if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
 791		netif_stop_queue(netdev);
 792
 793	err = usb_submit_urb(urb, GFP_ATOMIC);
 794	if (err) {
 795		can_free_echo_skb(netdev, context->echo_index);
 796
 797		atomic_dec(&priv->active_tx_jobs);
 798		usb_unanchor_urb(urb);
 799
 800		stats->tx_dropped++;
 801
 802		if (err == -ENODEV)
 803			netif_device_detach(netdev);
 804		else
 805			netdev_warn(netdev, "failed tx_urb %d\n", err);
 806
 807		goto releasebuf;
 808	}
 809
 810	netif_trans_update(netdev);
 811
 812	/*
 813	 * Release our reference to this URB, the USB core will eventually free
 814	 * it entirely.
 815	 */
 816	usb_free_urb(urb);
 817
 818	return NETDEV_TX_OK;
 819
 820releasebuf:
 821	usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
 822
 823nobufmem:
 824	usb_free_urb(urb);
 825
 826nourbmem:
 827	return ret;
 828}
 829
 830static int esd_usb2_close(struct net_device *netdev)
 831{
 832	struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 833	struct esd_usb2_msg *msg;
 834	int i;
 835
 836	msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 837	if (!msg)
 838		return -ENOMEM;
 839
 840	/* Disable all IDs (see esd_usb2_start()) */
 841	msg->msg.hdr.cmd = CMD_IDADD;
 842	msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 843	msg->msg.filter.net = priv->index;
 844	msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 845	for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
 846		msg->msg.filter.mask[i] = 0;
 847	if (esd_usb2_send_msg(priv->usb2, msg) < 0)
 848		netdev_err(netdev, "sending idadd message failed\n");
 849
 850	/* set CAN controller to reset mode */
 851	msg->msg.hdr.len = 2;
 852	msg->msg.hdr.cmd = CMD_SETBAUD;
 853	msg->msg.setbaud.net = priv->index;
 854	msg->msg.setbaud.rsvd = 0;
 855	msg->msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
 856	if (esd_usb2_send_msg(priv->usb2, msg) < 0)
 857		netdev_err(netdev, "sending setbaud message failed\n");
 858
 859	priv->can.state = CAN_STATE_STOPPED;
 860
 861	netif_stop_queue(netdev);
 862
 863	close_candev(netdev);
 864
 865	kfree(msg);
 866
 867	return 0;
 868}
 869
 870static const struct net_device_ops esd_usb2_netdev_ops = {
 871	.ndo_open = esd_usb2_open,
 872	.ndo_stop = esd_usb2_close,
 873	.ndo_start_xmit = esd_usb2_start_xmit,
 874	.ndo_change_mtu = can_change_mtu,
 875};
 876
 877static const struct can_bittiming_const esd_usb2_bittiming_const = {
 878	.name = "esd_usb2",
 879	.tseg1_min = ESD_USB2_TSEG1_MIN,
 880	.tseg1_max = ESD_USB2_TSEG1_MAX,
 881	.tseg2_min = ESD_USB2_TSEG2_MIN,
 882	.tseg2_max = ESD_USB2_TSEG2_MAX,
 883	.sjw_max = ESD_USB2_SJW_MAX,
 884	.brp_min = ESD_USB2_BRP_MIN,
 885	.brp_max = ESD_USB2_BRP_MAX,
 886	.brp_inc = ESD_USB2_BRP_INC,
 887};
 888
 889static int esd_usb2_set_bittiming(struct net_device *netdev)
 890{
 891	struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 892	struct can_bittiming *bt = &priv->can.bittiming;
 893	struct esd_usb2_msg *msg;
 894	int err;
 895	u32 canbtr;
 896	int sjw_shift;
 897
 898	canbtr = ESD_USB2_UBR;
 899	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 900		canbtr |= ESD_USB2_LOM;
 901
 902	canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
 903
 904	if (le16_to_cpu(priv->usb2->udev->descriptor.idProduct) ==
 905	    USB_CANUSBM_PRODUCT_ID)
 906		sjw_shift = ESD_USBM_SJW_SHIFT;
 907	else
 908		sjw_shift = ESD_USB2_SJW_SHIFT;
 909
 910	canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
 911		<< sjw_shift;
 912	canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
 913		   & (ESD_USB2_TSEG1_MAX - 1))
 914		<< ESD_USB2_TSEG1_SHIFT;
 915	canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
 916		<< ESD_USB2_TSEG2_SHIFT;
 917	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
 918		canbtr |= ESD_USB2_3_SAMPLES;
 919
 920	msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 921	if (!msg)
 922		return -ENOMEM;
 923
 924	msg->msg.hdr.len = 2;
 925	msg->msg.hdr.cmd = CMD_SETBAUD;
 926	msg->msg.setbaud.net = priv->index;
 927	msg->msg.setbaud.rsvd = 0;
 928	msg->msg.setbaud.baud = cpu_to_le32(canbtr);
 929
 930	netdev_info(netdev, "setting BTR=%#x\n", canbtr);
 931
 932	err = esd_usb2_send_msg(priv->usb2, msg);
 933
 934	kfree(msg);
 935	return err;
 936}
 937
 938static int esd_usb2_get_berr_counter(const struct net_device *netdev,
 939				     struct can_berr_counter *bec)
 940{
 941	struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 942
 943	bec->txerr = priv->bec.txerr;
 944	bec->rxerr = priv->bec.rxerr;
 945
 946	return 0;
 947}
 948
 949static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
 950{
 951	switch (mode) {
 952	case CAN_MODE_START:
 953		netif_wake_queue(netdev);
 954		break;
 955
 956	default:
 957		return -EOPNOTSUPP;
 958	}
 959
 960	return 0;
 961}
 962
 963static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
 964{
 965	struct esd_usb2 *dev = usb_get_intfdata(intf);
 966	struct net_device *netdev;
 967	struct esd_usb2_net_priv *priv;
 968	int err = 0;
 969	int i;
 970
 971	netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
 972	if (!netdev) {
 973		dev_err(&intf->dev, "couldn't alloc candev\n");
 974		err = -ENOMEM;
 975		goto done;
 976	}
 977
 978	priv = netdev_priv(netdev);
 979
 980	init_usb_anchor(&priv->tx_submitted);
 981	atomic_set(&priv->active_tx_jobs, 0);
 982
 983	for (i = 0; i < MAX_TX_URBS; i++)
 984		priv->tx_contexts[i].echo_index = MAX_TX_URBS;
 985
 986	priv->usb2 = dev;
 987	priv->netdev = netdev;
 988	priv->index = index;
 989
 990	priv->can.state = CAN_STATE_STOPPED;
 991	priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY;
 992
 993	if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
 994	    USB_CANUSBM_PRODUCT_ID)
 995		priv->can.clock.freq = ESD_USBM_CAN_CLOCK;
 996	else {
 997		priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
 998		priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
 999	}
1000
1001	priv->can.bittiming_const = &esd_usb2_bittiming_const;
1002	priv->can.do_set_bittiming = esd_usb2_set_bittiming;
1003	priv->can.do_set_mode = esd_usb2_set_mode;
1004	priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
1005
1006	netdev->flags |= IFF_ECHO; /* we support local echo */
1007
1008	netdev->netdev_ops = &esd_usb2_netdev_ops;
1009
1010	SET_NETDEV_DEV(netdev, &intf->dev);
1011	netdev->dev_id = index;
1012
1013	err = register_candev(netdev);
1014	if (err) {
1015		dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
1016		free_candev(netdev);
1017		err = -ENOMEM;
1018		goto done;
1019	}
1020
1021	dev->nets[index] = priv;
1022	netdev_info(netdev, "device %s registered\n", netdev->name);
1023
1024done:
1025	return err;
1026}
1027
1028/*
1029 * probe function for new USB2 devices
1030 *
1031 * check version information and number of available
1032 * CAN interfaces
1033 */
1034static int esd_usb2_probe(struct usb_interface *intf,
1035			 const struct usb_device_id *id)
1036{
1037	struct esd_usb2 *dev;
1038	struct esd_usb2_msg *msg;
1039	int i, err;
1040
1041	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1042	if (!dev) {
1043		err = -ENOMEM;
1044		goto done;
1045	}
1046
1047	dev->udev = interface_to_usbdev(intf);
1048
1049	init_usb_anchor(&dev->rx_submitted);
1050
1051	usb_set_intfdata(intf, dev);
1052
1053	msg = kmalloc(sizeof(*msg), GFP_KERNEL);
1054	if (!msg) {
1055		err = -ENOMEM;
1056		goto free_msg;
1057	}
1058
1059	/* query number of CAN interfaces (nets) */
1060	msg->msg.hdr.cmd = CMD_VERSION;
1061	msg->msg.hdr.len = 2;
1062	msg->msg.version.rsvd = 0;
1063	msg->msg.version.flags = 0;
1064	msg->msg.version.drv_version = 0;
1065
1066	err = esd_usb2_send_msg(dev, msg);
1067	if (err < 0) {
1068		dev_err(&intf->dev, "sending version message failed\n");
1069		goto free_msg;
1070	}
1071
1072	err = esd_usb2_wait_msg(dev, msg);
1073	if (err < 0) {
1074		dev_err(&intf->dev, "no version message answer\n");
1075		goto free_msg;
1076	}
1077
1078	dev->net_count = (int)msg->msg.version_reply.nets;
1079	dev->version = le32_to_cpu(msg->msg.version_reply.version);
1080
1081	if (device_create_file(&intf->dev, &dev_attr_firmware))
1082		dev_err(&intf->dev,
1083			"Couldn't create device file for firmware\n");
1084
1085	if (device_create_file(&intf->dev, &dev_attr_hardware))
1086		dev_err(&intf->dev,
1087			"Couldn't create device file for hardware\n");
1088
1089	if (device_create_file(&intf->dev, &dev_attr_nets))
1090		dev_err(&intf->dev,
1091			"Couldn't create device file for nets\n");
1092
1093	/* do per device probing */
1094	for (i = 0; i < dev->net_count; i++)
1095		esd_usb2_probe_one_net(intf, i);
1096
1097free_msg:
1098	kfree(msg);
1099	if (err)
1100		kfree(dev);
1101done:
1102	return err;
1103}
1104
1105/*
1106 * called by the usb core when the device is removed from the system
1107 */
1108static void esd_usb2_disconnect(struct usb_interface *intf)
1109{
1110	struct esd_usb2 *dev = usb_get_intfdata(intf);
1111	struct net_device *netdev;
1112	int i;
1113
1114	device_remove_file(&intf->dev, &dev_attr_firmware);
1115	device_remove_file(&intf->dev, &dev_attr_hardware);
1116	device_remove_file(&intf->dev, &dev_attr_nets);
1117
1118	usb_set_intfdata(intf, NULL);
1119
1120	if (dev) {
1121		for (i = 0; i < dev->net_count; i++) {
1122			if (dev->nets[i]) {
1123				netdev = dev->nets[i]->netdev;
1124				unregister_netdev(netdev);
1125				free_candev(netdev);
1126			}
1127		}
1128		unlink_all_urbs(dev);
1129		kfree(dev);
1130	}
1131}
1132
1133/* usb specific object needed to register this driver with the usb subsystem */
1134static struct usb_driver esd_usb2_driver = {
1135	.name = "esd_usb2",
1136	.probe = esd_usb2_probe,
1137	.disconnect = esd_usb2_disconnect,
1138	.id_table = esd_usb2_table,
1139};
1140
1141module_usb_driver(esd_usb2_driver);