diff mbox

[2/3,V3.1] can/usb: PEAK-System Technik PCAN-USB specific part

Message ID 1326968863-20229-3-git-send-email-s.grosjean@peak-system.com
State Awaiting Upstream, archived
Delegated to: David Miller
Headers show

Commit Message

Stéphane Grosjean Jan. 19, 2012, 10:27 a.m. UTC
This patch adds the specific part which handles the PCAN-USB adapter from
PEAK-System Technik (http://www.peak-system.com). The PCAN-USB adapter is
a sja1000 based, mono-channel USB 1.1 adapter compliant with CAN
specifications 2.0A (11-bit ID) and 2.0B (29-bit ID).

V3.1: same as V3 + add linux-can in cc:

Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
---
 drivers/net/can/usb/peak_usb/pcan_usb.c |  746 +++++++++++++++++++++++++++++++
 1 files changed, 746 insertions(+), 0 deletions(-)
 create mode 100644 drivers/net/can/usb/peak_usb/pcan_usb.c

Comments

Alan Stern Jan. 19, 2012, 3:07 p.m. UTC | #1
On Thu, 19 Jan 2012, Stephane Grosjean wrote:

> This patch adds the specific part which handles the PCAN-USB adapter from
> PEAK-System Technik (http://www.peak-system.com). The PCAN-USB adapter is
> a sja1000 based, mono-channel USB 1.1 adapter compliant with CAN
> specifications 2.0A (11-bit ID) and 2.0B (29-bit ID).
> 
> V3.1: same as V3 + add linux-can in cc:
> +/*
> + * send a command
> + */
> +static int pcan_usb_send_cmd(struct peak_usb_device *dev, u8 f, u8 n, u8 *p)
> +{
> +	int err;
> +	int actual_length;
> +	struct pcan_usb_parameter cmd = {
> +		.function = f,
> +		.number = n,
> +	};
> +
> +	/* usb device unregistered? */
> +	if (!(dev->state & PCAN_USB_STATE_CONNECTED))
> +		return 0;
> +
> +	if (p)
> +		memcpy(cmd.parameters, p, ARRAY_SIZE(cmd.parameters));
> +
> +	err = usb_bulk_msg(dev->udev,
> +		usb_sndbulkpipe(dev->udev, PCAN_USB_EP_CMDOUT), &cmd,
> +		sizeof(struct pcan_usb_parameter), &actual_length,
> +		PCAN_USB_COMMAND_TIMEOUT);

Here, and in several other places in this patch series, you submit
requests using a transfer buffer that is allocated on the stack.  This
is forbidden because not all platforms can do DMA to stack or static
addresses.  The transfer buffers should be allocated dynamically.

Alan Stern

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diff mbox

Patch

diff --git a/drivers/net/can/usb/peak_usb/pcan_usb.c b/drivers/net/can/usb/peak_usb/pcan_usb.c
new file mode 100644
index 0000000..12737aa
--- /dev/null
+++ b/drivers/net/can/usb/peak_usb/pcan_usb.c
@@ -0,0 +1,746 @@ 
+/*
+ * CAN driver for PEAK System PCAN-USB adapter
+ * Derived from the PCAN project file driver/src/pcan_usb.c
+ *
+ * Copyright (C) 2003-2010 PEAK System-Technik GmbH
+ * Copyright (C) 2011-2012 Stephane Grosjean <s.grosjean@peak-system.com>
+ *
+ * Many thanks to Klaus Hitschler <klaus.hitschler@gmx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+#include <linux/netdevice.h>
+#include <linux/usb.h>
+#include <linux/module.h>
+
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+
+#include "pcan_usb_core.h"
+
+MODULE_SUPPORTED_DEVICE("PEAK-System PCAN-USB adapter");
+
+/* PCAN-USB Endpoints */
+#define PCAN_USB_EP_CMDOUT		1
+#define PCAN_USB_EP_CMDIN		(PCAN_USB_EP_CMDOUT | USB_DIR_IN)
+#define PCAN_USB_EP_MSGOUT		2
+#define PCAN_USB_EP_MSGIN		(PCAN_USB_EP_MSGOUT | USB_DIR_IN)
+
+/* PCAN-USB parameter command */
+#define PCAN_USB_PARAMETER_LEN		14
+struct __packed pcan_usb_parameter {
+	u8 function;
+	u8 number;
+	u8 parameters[PCAN_USB_PARAMETER_LEN];
+};
+
+/* PCAN-USB command timeout (ms.) */
+#define PCAN_USB_COMMAND_TIMEOUT	1000
+
+/* PCAN-USB rx/tx buffers size */
+#define PCAN_USB_RX_BUFFER_SIZE		64
+#define PCAN_USB_TX_BUFFER_SIZE		64
+
+#define PCAN_USB_MSG_HEADER_LEN		2
+
+/* PCAN-USB adapter internal clock (MHz) */
+#define PCAN_USB_CRYSTAL_HZ		16000000
+
+/* PCAN-USB USB message record status/len field */
+#define PCAN_USB_STATUSLEN_TIMESTAMP	(1 << 7)
+#define PCAN_USB_STATUSLEN_INTERNAL	(1 << 6)
+#define PCAN_USB_STATUSLEN_EXT_ID	(1 << 5)
+#define PCAN_USB_STATUSLEN_RTR		(1 << 4)
+#define PCAN_USB_STATUSLEN_DLC		(0xf)
+
+/* PCAN-USB error flags */
+#define PCAN_USB_ERROR_TXFULL		0x01
+#define PCAN_USB_ERROR_RXQOVR		0x02
+#define PCAN_USB_ERROR_BUS_LIGHT	0x04
+#define PCAN_USB_ERROR_BUS_HEAVY	0x08
+#define PCAN_USB_ERROR_BUS_OFF		0x10
+#define PCAN_USB_ERROR_RXQEMPTY		0x20
+#define PCAN_USB_ERROR_QOVR		0x40
+#define PCAN_USB_ERROR_TXQFULL		0x80
+
+/* SJA1000 modes */
+#define SJA1000_MODE_NORMAL		0x00
+#define SJA1000_MODE_INIT		0x01
+
+/*
+ * tick duration = 42.666 us =>
+ * (tick_number * 44739243) >> 20 ~ (tick_number * 42666) / 1000
+ * accuracy = 10^-7
+ */
+#define PCAN_USB_TS_DIV_SHIFTER		20
+#define PCAN_USB_TS_US_PER_TICK		44739243
+
+/* PCAN-USB messages record types */
+#define PCAN_USB_REC_ERROR		1
+#define PCAN_USB_REC_ANALOG		2
+#define PCAN_USB_REC_BUSLOAD		3
+#define PCAN_USB_REC_TS			4
+#define PCAN_USB_REC_BUSEVT		5
+
+/* private to PCAN-USB adapter */
+struct pcan_usb {
+	struct peak_usb_device dev;
+	struct peak_time_ref time_ref;
+};
+
+/* incoming message context for decoding */
+struct pcan_usb_msg_context {
+	u16 ts16;
+	u8 prev_ts8;
+	u8 *ptr;
+	u8 *end;
+	u8 rec_cnt;
+	u8 rec_idx;
+	u8 rec_data_idx;
+	struct net_device *netdev;
+	struct pcan_usb *pdev;
+};
+
+/*
+ * send a command
+ */
+static int pcan_usb_send_cmd(struct peak_usb_device *dev, u8 f, u8 n, u8 *p)
+{
+	int err;
+	int actual_length;
+	struct pcan_usb_parameter cmd = {
+		.function = f,
+		.number = n,
+	};
+
+	/* usb device unregistered? */
+	if (!(dev->state & PCAN_USB_STATE_CONNECTED))
+		return 0;
+
+	if (p)
+		memcpy(cmd.parameters, p, ARRAY_SIZE(cmd.parameters));
+
+	err = usb_bulk_msg(dev->udev,
+		usb_sndbulkpipe(dev->udev, PCAN_USB_EP_CMDOUT), &cmd,
+		sizeof(struct pcan_usb_parameter), &actual_length,
+		PCAN_USB_COMMAND_TIMEOUT);
+	if (err)
+		netdev_err(dev->netdev,
+			"sending cmd f=0x%x n=0x%x failure: %d\n",
+			f, n, err);
+
+	return err;
+}
+
+/*
+ * send a command then wait for its response
+ */
+static int pcan_usb_wait_rsp(struct peak_usb_device *dev, u8 f, u8 n, u8 *p)
+{
+	int err;
+	int actual_length;
+	struct pcan_usb_parameter cmd = {
+		.function = f,
+		.number = n,
+	};
+
+	/* usb device unregistered? */
+	if (!(dev->state & PCAN_USB_STATE_CONNECTED))
+		return 0;
+
+	/* first, send command */
+	err = pcan_usb_send_cmd(dev, f, n, NULL);
+	if (err)
+		return err;
+
+	err = usb_bulk_msg(dev->udev,
+		usb_rcvbulkpipe(dev->udev, PCAN_USB_EP_CMDIN), &cmd,
+		sizeof(struct pcan_usb_parameter), &actual_length,
+		PCAN_USB_COMMAND_TIMEOUT);
+	if (err)
+		netdev_err(dev->netdev,
+			"waiting rsp f=0x%x n=0x%x failure: %d\n", f, n, err);
+	else if (p)
+		memcpy(p, cmd.parameters, ARRAY_SIZE(cmd.parameters));
+
+	return err;
+}
+
+static int pcan_usb_set_sja1000(struct peak_usb_device *dev, u8 mode)
+{
+	u8 args[PCAN_USB_PARAMETER_LEN] = {
+		[1] = mode,
+	};
+
+	return pcan_usb_send_cmd(dev, 9, 2, args);
+}
+
+static int pcan_usb_set_bus(struct peak_usb_device *dev, u8 onoff)
+{
+	u8 args[PCAN_USB_PARAMETER_LEN] = {
+		[0] = onoff ? 1 : 0,
+	};
+
+	return pcan_usb_send_cmd(dev, 3, 2, args);
+}
+
+static int pcan_usb_set_silent(struct peak_usb_device *dev, u8 onoff)
+{
+	u8 args[PCAN_USB_PARAMETER_LEN] = {
+		[0] = onoff ? 1 : 0,
+	};
+
+	return pcan_usb_send_cmd(dev, 3, 3, args);
+}
+
+static int pcan_usb_set_ext_vcc(struct peak_usb_device *dev, u8 onoff)
+{
+	u8 args[PCAN_USB_PARAMETER_LEN] = {
+		[0] = onoff ? 1 : 0,
+	};
+
+	return pcan_usb_send_cmd(dev, 10, 2, args);
+}
+
+/*
+ * set bittiming value to can
+ */
+static int pcan_usb_set_bittiming(struct peak_usb_device *dev,
+				  struct can_bittiming *bt)
+{
+	u8 args[PCAN_USB_PARAMETER_LEN];
+	u8 btr0, btr1;
+
+	btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
+	btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
+		(((bt->phase_seg2 - 1) & 0x7) << 4);
+	if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
+		btr1 |= 0x80;
+
+	netdev_info(dev->netdev, "setting BTR0=0x%02x BTR1=0x%02x\n",
+		btr0, btr1);
+
+	args[0] = btr1;
+	args[1] = btr0;
+
+	return pcan_usb_send_cmd(dev, 1, 2, args);
+}
+
+/*
+ * init/reset can
+ */
+static int pcan_usb_write_mode(struct peak_usb_device *dev, u8 onoff)
+{
+	int err;
+
+	err = pcan_usb_set_bus(dev, onoff);
+	if (err)
+		return err;
+
+	if (!onoff)
+		err = pcan_usb_set_sja1000(dev, SJA1000_MODE_INIT);
+
+	return err;
+}
+
+/*
+ * read serial number from device
+ */
+static int pcan_usb_get_serial(struct peak_usb_device *dev, u32 *serial_number)
+{
+	u8 args[PCAN_USB_PARAMETER_LEN];
+	int err;
+
+	err = pcan_usb_wait_rsp(dev, 6, 1, args);
+	if (err) {
+		netdev_err(dev->netdev, "getting serial failure: %d\n", err);
+	} else if (serial_number) {
+		u32 tmp32;
+
+		memcpy(&tmp32, args, 4);
+		*serial_number = le32_to_cpu(tmp32);
+	}
+
+	return err;
+}
+
+/*
+ * read device id from device
+ */
+static int pcan_usb_get_device_id(struct peak_usb_device *dev, u32 *device_id)
+{
+	u8 args[PCAN_USB_PARAMETER_LEN];
+	int err;
+
+	err = pcan_usb_wait_rsp(dev, 4, 1, args);
+	if (err)
+		netdev_err(dev->netdev, "getting device id failure: %d\n", err);
+	else if (device_id)
+		*device_id = args[0];
+
+	return err;
+}
+
+/*
+ * update current time ref with received timestamp
+ */
+static int pcan_usb_update_ts(struct pcan_usb_msg_context *mc)
+{
+	u16 tmp16;
+
+	if ((mc->ptr+2) > mc->end)
+		return -EINVAL;
+
+	memcpy(&tmp16, mc->ptr, 2);
+
+	mc->ts16 = le16_to_cpu(tmp16);
+
+	if (mc->rec_idx > 0)
+		peak_usb_update_ts_now(&mc->pdev->time_ref, mc->ts16);
+	else
+		peak_usb_set_ts_now(&mc->pdev->time_ref, mc->ts16);
+
+	return 0;
+}
+
+/*
+ * decode received timestamp
+ */
+static int pcan_usb_decode_ts(struct pcan_usb_msg_context *mc, u8 first_packet)
+{
+	/* only 1st packet supplies a word timestamp */
+	if (first_packet) {
+		u16 tmp16;
+
+		if ((mc->ptr + 2) > mc->end)
+			return -EINVAL;
+
+		memcpy(&tmp16, mc->ptr, 2);
+		mc->ptr += 2;
+
+		mc->ts16 = le16_to_cpu(tmp16);
+		mc->prev_ts8 = mc->ts16 & 0x00ff;
+	} else {
+		u8 ts8;
+
+		if ((mc->ptr + 1) > mc->end)
+			return -EINVAL;
+
+		ts8 = *mc->ptr++;
+
+		if (ts8 < mc->prev_ts8)
+			mc->ts16 += 0x100;
+
+		mc->ts16 &= 0xff00;
+		mc->ts16 |= ts8;
+		mc->prev_ts8 = ts8;
+	}
+
+	return 0;
+}
+
+/*
+ * decode non-data usb message
+ */
+static int pcan_usb_decode_status(struct pcan_usb_msg_context *mc,
+				  u8 status_len)
+{
+	u8 rec_len = status_len & PCAN_USB_STATUSLEN_DLC;
+	struct sk_buff *skb;
+	struct can_frame *cf;
+	struct timeval tv;
+	u8 f, n;
+
+	/* check whether function and number can be read */
+	if ((mc->ptr + 2) > mc->end)
+		return -EINVAL;
+
+	f = mc->ptr[0];
+	n = mc->ptr[1];
+	mc->ptr += 2;
+
+	if (status_len & PCAN_USB_STATUSLEN_TIMESTAMP) {
+		int err = pcan_usb_decode_ts(mc, !mc->rec_idx);
+
+		if (err)
+			return err;
+	}
+
+	switch (f) {
+	case PCAN_USB_REC_ERROR:
+		/* no status flag => ignore record */
+		if (!n)
+			break;
+
+		/* ignore this error until 1st ts received */
+		if (n == PCAN_USB_ERROR_QOVR)
+			if (!mc->pdev->time_ref.tick_count)
+				break;
+
+		/* allocate an skb to store the error frame */
+		skb = alloc_can_err_skb(mc->netdev, &cf);
+		if (!skb)
+			return -ENOMEM;
+
+		if (n & (PCAN_USB_ERROR_RXQOVR | PCAN_USB_ERROR_QOVR)) {
+			cf->can_id |= CAN_ERR_CRTL;
+			cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
+			mc->netdev->stats.rx_over_errors++;
+			mc->netdev->stats.rx_errors++;
+		}
+		if (n & PCAN_USB_ERROR_BUS_OFF) {
+			cf->can_id |= CAN_ERR_BUSOFF;
+			can_bus_off(mc->netdev);
+		}
+		if (n & PCAN_USB_ERROR_BUS_HEAVY) {
+			cf->can_id |= CAN_ERR_CRTL;
+			cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE |
+					CAN_ERR_CRTL_RX_PASSIVE;
+			mc->pdev->dev.can.can_stats.error_passive++;
+		}
+		if (n & PCAN_USB_ERROR_BUS_LIGHT) {
+			cf->can_id |= CAN_ERR_CRTL;
+			cf->data[1] |= CAN_ERR_CRTL_TX_WARNING |
+					CAN_ERR_CRTL_RX_WARNING;
+			mc->pdev->dev.can.can_stats.error_warning++;
+		}
+
+		if (status_len & PCAN_USB_STATUSLEN_TIMESTAMP) {
+			peak_usb_get_ts_tv(&mc->pdev->time_ref, mc->ts16, &tv);
+			skb->tstamp = timeval_to_ktime(tv);
+		}
+		netif_rx(skb);
+		mc->netdev->stats.rx_packets++;
+		mc->netdev->stats.rx_bytes += cf->can_dlc;
+		break;
+
+	case PCAN_USB_REC_ANALOG:
+		/* analog values (ignored) */
+		rec_len = 2;
+		break;
+
+	case PCAN_USB_REC_BUSLOAD:
+		/* bus load (ignored) */
+		rec_len = 1;
+		break;
+
+	case PCAN_USB_REC_TS:
+		/* only timestamp */
+		if (pcan_usb_update_ts(mc))
+			return -EINVAL;
+		break;
+
+	case PCAN_USB_REC_BUSEVT:
+		/* error frame/bus event */
+		if (n & PCAN_USB_ERROR_TXQFULL)
+			netdev_dbg(mc->netdev, "device Tx queue full)\n");
+		break;
+	default:
+		netdev_err(mc->netdev, "unexpected function %u\n", f);
+		break;
+	}
+
+	if ((mc->ptr + rec_len) > mc->end)
+		return -EINVAL;
+
+	mc->ptr += rec_len;
+
+	return 0;
+}
+
+/*
+ * decode data usb message
+ */
+static int pcan_usb_decode_data(struct pcan_usb_msg_context *mc, u8 status_len)
+{
+	u8 rec_len = status_len & PCAN_USB_STATUSLEN_DLC;
+	struct sk_buff *skb;
+	struct can_frame *cf;
+	struct timeval tv;
+
+	skb = alloc_can_skb(mc->netdev, &cf);
+	if (!skb)
+		return -ENOMEM;
+
+	if (status_len & PCAN_USB_STATUSLEN_EXT_ID) {
+		u32 tmp32;
+
+		if ((mc->ptr + 4) > mc->end)
+			goto decode_failed;
+
+		memcpy(&tmp32, mc->ptr, 4);
+		mc->ptr += 4;
+
+		cf->can_id = le32_to_cpu(tmp32 >> 3) | CAN_EFF_FLAG;
+	} else {
+		u16 tmp16;
+
+		if ((mc->ptr + 2) > mc->end)
+			goto decode_failed;
+
+		memcpy(&tmp16, mc->ptr, 2);
+		mc->ptr += 2;
+
+		cf->can_id = le16_to_cpu(tmp16 >> 5);
+	}
+
+	cf->can_dlc = get_can_dlc(rec_len);
+
+	/* first data packet timestamp is a word */
+	if (pcan_usb_decode_ts(mc, !mc->rec_data_idx))
+		goto decode_failed;
+
+	/* read data */
+	memset(cf->data, 0x0, sizeof(cf->data));
+	if (status_len & PCAN_USB_STATUSLEN_RTR) {
+		cf->can_id |= CAN_RTR_FLAG;
+	} else {
+		if ((mc->ptr + rec_len) > mc->end)
+			goto decode_failed;
+
+		memcpy(cf->data, mc->ptr, rec_len);
+		mc->ptr += rec_len;
+	}
+
+	/* convert timestamp into kernel time */
+	peak_usb_get_ts_tv(&mc->pdev->time_ref, mc->ts16, &tv);
+	skb->tstamp = timeval_to_ktime(tv);
+
+	/* push the skb */
+	netif_rx(skb);
+
+	/* update statistics */
+	mc->netdev->stats.rx_packets++;
+	mc->netdev->stats.rx_bytes += cf->can_dlc;
+
+	return 0;
+
+decode_failed:
+	dev_kfree_skb(skb);
+	return -EINVAL;
+}
+
+/*
+ * process incoming message
+ */
+static int pcan_usb_decode_msg(struct peak_usb_device *dev, u8 *ibuf, u32 lbuf)
+{
+	struct pcan_usb_msg_context mc = {
+		.rec_cnt = ibuf[1],
+		.ptr = ibuf + PCAN_USB_MSG_HEADER_LEN,
+		.end = ibuf + lbuf,
+		.netdev = dev->netdev,
+		.pdev = container_of(dev, struct pcan_usb, dev),
+	};
+	int err;
+
+	for (err = 0; mc.rec_idx < mc.rec_cnt && !err; mc.rec_idx++) {
+		u8 sl = *mc.ptr++;
+
+		/* handle status and error frames here */
+		if (sl & PCAN_USB_STATUSLEN_INTERNAL) {
+			err = pcan_usb_decode_status(&mc, sl);
+		/* handle normal can frames here */
+		} else {
+			err = pcan_usb_decode_data(&mc, sl);
+			mc.rec_data_idx++;
+		}
+	}
+
+	return err;
+}
+
+/*
+ * process any incoming buffer
+ */
+static int pcan_usb_decode_buf(struct peak_usb_device *dev, struct urb *urb)
+{
+	int err = 0;
+
+	if (urb->actual_length > PCAN_USB_MSG_HEADER_LEN) {
+		err = pcan_usb_decode_msg(dev, urb->transfer_buffer,
+			urb->actual_length);
+
+	} else if (urb->actual_length > 0) {
+		netdev_err(dev->netdev, "usb message length error (%u)\n",
+			urb->actual_length);
+		err = -EINVAL;
+	}
+
+	return err;
+}
+
+/*
+ * process outgoing packet
+ */
+static int pcan_usb_encode_msg(struct peak_usb_device *dev, struct sk_buff *skb,
+			       u8 *obuf, size_t *size)
+{
+	struct net_device *netdev = dev->netdev;
+	struct net_device_stats *stats = &netdev->stats;
+	struct can_frame *cf = (struct can_frame *)skb->data;
+	u8 *pc;
+
+	obuf[0] = 2;
+	obuf[1] = 1;
+
+	pc = obuf + PCAN_USB_MSG_HEADER_LEN;
+
+	/* status/len byte */
+	*pc = cf->can_dlc;
+	if (cf->can_id & CAN_RTR_FLAG)
+		*pc |= PCAN_USB_STATUSLEN_RTR;
+
+	/* can id */
+	if (cf->can_id & CAN_EFF_FLAG) {
+		__le32 tmp32 = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
+
+		tmp32 <<= 3;
+		*pc |= PCAN_USB_STATUSLEN_EXT_ID;
+		memcpy(++pc, &tmp32, 4);
+		pc += 4;
+	} else {
+		__le16 tmp16 = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
+
+		tmp16 <<= 5;
+		memcpy(++pc, &tmp16, 2);
+		pc += 2;
+	}
+
+	/* can data */
+	if (!(cf->can_id & CAN_RTR_FLAG)) {
+		memcpy(pc, cf->data, cf->can_dlc);
+		pc += cf->can_dlc;
+	}
+
+	obuf[(*size)-1] = (u8)(stats->tx_packets & 0xff);
+
+	return 0;
+}
+
+/*
+ * start interface
+ */
+static int pcan_usb_start(struct peak_usb_device *dev)
+{
+	struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev);
+
+	/* number of bits used in timestamps read from adapter struct */
+	peak_usb_init_time_ref(&pdev->time_ref, &pcan_usb);
+
+	/* if revision greater than 3, can put silent mode on/off */
+	if (dev->device_rev > 3) {
+		int err;
+
+		err = pcan_usb_set_silent(dev,
+				dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY);
+		if (err)
+			return err;
+	}
+
+	return pcan_usb_set_ext_vcc(dev, 0);
+}
+
+static int pcan_usb_init(struct peak_usb_device *dev)
+{
+	u32 serial_number;
+	int err;
+
+	/*
+	 * explicit use of dev_info() instead of netdev_info() here:
+	 * information displayed are related to the device itself, not
+	 * to the canx netdevice.
+	 */
+	err = pcan_usb_get_serial(dev, &serial_number);
+	if (!err)
+		dev_info(dev->netdev->dev.parent, "serial %08X hwrev %u\n",
+			serial_number, dev->device_rev);
+
+	return err;
+}
+
+/*
+ * probe function for new PCAN-USB usb interface
+ */
+static int pcan_usb_probe(struct usb_interface *intf)
+{
+	struct usb_host_interface *if_desc;
+	int i;
+
+	if_desc = intf->altsetting;
+
+	/* check interface endpoint addresses */
+	for (i = 0; i < if_desc->desc.bNumEndpoints; i++) {
+		struct usb_endpoint_descriptor *ep = &if_desc->endpoint[i].desc;
+
+		switch (ep->bEndpointAddress) {
+		case PCAN_USB_EP_CMDOUT:
+		case PCAN_USB_EP_CMDIN:
+		case PCAN_USB_EP_MSGOUT:
+		case PCAN_USB_EP_MSGIN:
+			break;
+		default:
+			return -ENODEV;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * describe the PCAN-USB adapter
+ */
+struct peak_usb_adapter pcan_usb = {
+	.name = "PCAN-USB",
+	.device_id = PCAN_USB_PRODUCT_ID,
+	.ctrl_count = 1,
+	.clock = {
+		.freq = PCAN_USB_CRYSTAL_HZ / 2 ,
+	},
+	.bittiming_const = {
+		.name = "pcan_usb",
+		.tseg1_min = 1,
+		.tseg1_max = 16,
+		.tseg2_min = 1,
+		.tseg2_max = 8,
+		.sjw_max = 4,
+		.brp_min = 1,
+		.brp_max = 64,
+		.brp_inc = 1,
+	},
+
+	/* size of device private data */
+	.sizeof_dev_private = sizeof(struct pcan_usb),
+
+	/* timestamps usage */
+	.ts_used_bits = 16,
+	.ts_period = 24575, /* calibration period in ts. */
+	.us_per_ts_scale = PCAN_USB_TS_US_PER_TICK, /* us=(ts*scale) */
+	.us_per_ts_shift = PCAN_USB_TS_DIV_SHIFTER, /*  >> shift     */
+
+	/* give here commands/messages in/out endpoints */
+	.ep_msg_in = PCAN_USB_EP_MSGIN,
+	.ep_msg_out = {PCAN_USB_EP_MSGOUT},
+
+	/* size of rx/tx usb buffers */
+	.rx_buffer_size = PCAN_USB_RX_BUFFER_SIZE,
+	.tx_buffer_size = PCAN_USB_TX_BUFFER_SIZE,
+
+	/* device callbacks */
+	.intf_probe = pcan_usb_probe,
+	.dev_init = pcan_usb_init,
+	.dev_set_bus = pcan_usb_write_mode,
+	.dev_set_bittiming = pcan_usb_set_bittiming,
+	.dev_get_device_id = pcan_usb_get_device_id,
+	.dev_decode_buf = pcan_usb_decode_buf,
+	.dev_encode_msg = pcan_usb_encode_msg,
+	.dev_start = pcan_usb_start,
+};