can: kvaser_usb: Split driver into kvaser_usb_core.c and kvaser_usb_leaf.c

First part of adding support for Kvaser USB device family "hydra".

Split kvaser_usb.c into kvaser_usb/kvaser_usb{.h,_core.c,_leaf.c}.

kvaser_usb_core.c contains common functionality, such as USB
writing/reading and allocation of netdev.
kvaser_usb_leaf.c contains device specific code, used in
kvaser_usb_core.c.

struct kvaser_usb_dev_ops contains device specific functions that are
common for all devices in the family. While, struct kvaser_usb_dev_cfg
describes the device configurations in terms of CAN clock frequency,
timestamp frequency and CAN controller bittiming constants.

Signed-off-by: Jimmy Assarsson <[e-mail]>
Signed-off-by: Marc Kleine-Budde <[e-mail]>

drivers/net/can/usb/Makefile

···
 obj-$(CONFIG_CAN_EMS_USB) += ems_usb.o
 obj-$(CONFIG_CAN_ESD_USB2) += esd_usb2.o
 obj-$(CONFIG_CAN_GS_USB) += gs_usb.o
-obj-$(CONFIG_CAN_KVASER_USB) += kvaser_usb.o
+obj-$(CONFIG_CAN_KVASER_USB) += kvaser_usb/
 obj-$(CONFIG_CAN_MCBA_USB) += mcba_usb.o
 obj-$(CONFIG_CAN_PEAK_USB) += peak_usb/
 obj-$(CONFIG_CAN_UCAN) += ucan.o

drivers/net/can/usb/kvaser_usb.c

···
-// SPDX-License-Identifier: GPL-2.0
-/* Parts of this driver are based on the following:
- *  - Kvaser linux leaf driver (version 4.78)
- *  - CAN driver for esd CAN-USB/2
- *  - Kvaser linux usbcanII driver (version 5.3)
- *
- * Copyright (C) 2002-2006 KVASER AB, Sweden. All rights reserved.
- * Copyright (C) 2010 Matthias Fuchs <[e-mail]>, esd gmbh
- * Copyright (C) 2012 Olivier Sobrie <[e-mail]>
- * Copyright (C) 2015 Valeo S.A.
- */
-
-#include <linux/spinlock.h>
-#include <linux/kernel.h>
-#include <linux/completion.h>
-#include <linux/module.h>
-#include <linux/netdevice.h>
-#include <linux/usb.h>
-
-#include <linux/can.h>
-#include <linux/can/dev.h>
-#include <linux/can/error.h>
-
-#define MAX_RX_URBS			4
-#define KVASER_USB_TIMEOUT		1000 /* msecs */
-#define RX_BUFFER_SIZE			3072
-#define CAN_USB_CLOCK			8000000
-#define MAX_NET_DEVICES			3
-#define MAX_USBCAN_NET_DEVICES		2
-
-/* Kvaser Leaf USB devices */
-#define KVASER_VENDOR_ID		0x0bfd
-#define USB_LEAF_DEVEL_PRODUCT_ID	10
-#define USB_LEAF_LITE_PRODUCT_ID	11
-#define USB_LEAF_PRO_PRODUCT_ID		12
-#define USB_LEAF_SPRO_PRODUCT_ID	14
-#define USB_LEAF_PRO_LS_PRODUCT_ID	15
-#define USB_LEAF_PRO_SWC_PRODUCT_ID	16
-#define USB_LEAF_PRO_LIN_PRODUCT_ID	17
-#define USB_LEAF_SPRO_LS_PRODUCT_ID	18
-#define USB_LEAF_SPRO_SWC_PRODUCT_ID	19
-#define USB_MEMO2_DEVEL_PRODUCT_ID	22
-#define USB_MEMO2_HSHS_PRODUCT_ID	23
-#define USB_UPRO_HSHS_PRODUCT_ID	24
-#define USB_LEAF_LITE_GI_PRODUCT_ID	25
-#define USB_LEAF_PRO_OBDII_PRODUCT_ID	26
-#define USB_MEMO2_HSLS_PRODUCT_ID	27
-#define USB_LEAF_LITE_CH_PRODUCT_ID	28
-#define USB_BLACKBIRD_SPRO_PRODUCT_ID	29
-#define USB_OEM_MERCURY_PRODUCT_ID	34
-#define USB_OEM_LEAF_PRODUCT_ID		35
-#define USB_CAN_R_PRODUCT_ID		39
-#define USB_LEAF_LITE_V2_PRODUCT_ID	288
-#define USB_MINI_PCIE_HS_PRODUCT_ID	289
-#define USB_LEAF_LIGHT_HS_V2_OEM_PRODUCT_ID 290
-#define USB_USBCAN_LIGHT_2HS_PRODUCT_ID	291
-#define USB_MINI_PCIE_2HS_PRODUCT_ID	292
-
-static inline bool kvaser_is_leaf(const struct usb_device_id *id)
-{
-	return id->idProduct >= USB_LEAF_DEVEL_PRODUCT_ID &&
-	       id->idProduct <= USB_MINI_PCIE_2HS_PRODUCT_ID;
-}
-
-/* Kvaser USBCan-II devices */
-#define USB_USBCAN_REVB_PRODUCT_ID	2
-#define USB_VCI2_PRODUCT_ID		3
-#define USB_USBCAN2_PRODUCT_ID		4
-#define USB_MEMORATOR_PRODUCT_ID	5
-
-static inline bool kvaser_is_usbcan(const struct usb_device_id *id)
-{
-	return id->idProduct >= USB_USBCAN_REVB_PRODUCT_ID &&
-	       id->idProduct <= USB_MEMORATOR_PRODUCT_ID;
-}
-
-/* USB devices features */
-#define KVASER_HAS_SILENT_MODE		BIT(0)
-#define KVASER_HAS_TXRX_ERRORS		BIT(1)
-
-/* Command header size */
-#define CMD_HEADER_LEN			2
-
-/* CAN message flags */
-#define MSG_FLAG_ERROR_FRAME		BIT(0)
-#define MSG_FLAG_OVERRUN		BIT(1)
-#define MSG_FLAG_NERR			BIT(2)
-#define MSG_FLAG_WAKEUP			BIT(3)
-#define MSG_FLAG_REMOTE_FRAME		BIT(4)
-#define MSG_FLAG_RESERVED		BIT(5)
-#define MSG_FLAG_TX_ACK			BIT(6)
-#define MSG_FLAG_TX_REQUEST		BIT(7)
-
-/* CAN states (M16C CxSTRH register) */
-#define M16C_STATE_BUS_RESET		BIT(0)
-#define M16C_STATE_BUS_ERROR		BIT(4)
-#define M16C_STATE_BUS_PASSIVE		BIT(5)
-#define M16C_STATE_BUS_OFF		BIT(6)
-
-/* Leaf/usbcan command ids */
-#define CMD_RX_STD_MESSAGE		12
-#define CMD_TX_STD_MESSAGE		13
-#define CMD_RX_EXT_MESSAGE		14
-#define CMD_TX_EXT_MESSAGE		15
-#define CMD_SET_BUS_PARAMS		16
-#define CMD_CHIP_STATE_EVENT		20
-#define CMD_SET_CTRL_MODE		21
-#define CMD_RESET_CHIP			24
-#define CMD_START_CHIP			26
-#define CMD_START_CHIP_REPLY		27
-#define CMD_STOP_CHIP			28
-#define CMD_STOP_CHIP_REPLY		29
-
-#define CMD_USBCAN_CLOCK_OVERFLOW_EVENT	33
-
-#define CMD_GET_CARD_INFO		34
-#define CMD_GET_CARD_INFO_REPLY		35
-#define CMD_GET_SOFTWARE_INFO		38
-#define CMD_GET_SOFTWARE_INFO_REPLY	39
-#define CMD_FLUSH_QUEUE			48
-#define CMD_TX_ACKNOWLEDGE		50
-#define CMD_CAN_ERROR_EVENT		51
-#define CMD_FLUSH_QUEUE_REPLY		68
-
-#define CMD_LEAF_LOG_MESSAGE		106
-
-/* error factors */
-#define M16C_EF_ACKE			BIT(0)
-#define M16C_EF_CRCE			BIT(1)
-#define M16C_EF_FORME			BIT(2)
-#define M16C_EF_STFE			BIT(3)
-#define M16C_EF_BITE0			BIT(4)
-#define M16C_EF_BITE1			BIT(5)
-#define M16C_EF_RCVE			BIT(6)
-#define M16C_EF_TRE			BIT(7)
-
-/* Only Leaf-based devices can report M16C error factors,
- * thus define our own error status flags for USBCANII
- */
-#define USBCAN_ERROR_STATE_NONE		0
-#define USBCAN_ERROR_STATE_TX_ERROR	BIT(0)
-#define USBCAN_ERROR_STATE_RX_ERROR	BIT(1)
-#define USBCAN_ERROR_STATE_BUSERROR	BIT(2)
-
-/* bittiming parameters */
-#define KVASER_USB_TSEG1_MIN		1
-#define KVASER_USB_TSEG1_MAX		16
-#define KVASER_USB_TSEG2_MIN		1
-#define KVASER_USB_TSEG2_MAX		8
-#define KVASER_USB_SJW_MAX		4
-#define KVASER_USB_BRP_MIN		1
-#define KVASER_USB_BRP_MAX		64
-#define KVASER_USB_BRP_INC		1
-
-/* ctrl modes */
-#define KVASER_CTRL_MODE_NORMAL		1
-#define KVASER_CTRL_MODE_SILENT		2
-#define KVASER_CTRL_MODE_SELFRECEPTION	3
-#define KVASER_CTRL_MODE_OFF		4
-
-/* Extended CAN identifier flag */
-#define KVASER_EXTENDED_FRAME		BIT(31)
-
-/* Kvaser USB CAN dongles are divided into two major families:
- * - Leaf: Based on Renesas M32C, running firmware labeled as 'filo'
- * - UsbcanII: Based on Renesas M16C, running firmware labeled as 'helios'
- */
-enum kvaser_usb_family {
-	KVASER_LEAF,
-	KVASER_USBCAN,
-};
-
-struct kvaser_cmd_simple {
-	u8 tid;
-	u8 channel;
-} __packed;
-
-struct kvaser_cmd_cardinfo {
-	u8 tid;
-	u8 nchannels;
-	union {
-		struct {
-			__le32 serial_number;
-			__le32 padding;
-		} __packed leaf0;
-		struct {
-			__le32 serial_number_low;
-			__le32 serial_number_high;
-		} __packed usbcan0;
-	} __packed;
-	__le32 clock_resolution;
-	__le32 mfgdate;
-	u8 ean[8];
-	u8 hw_revision;
-	union {
-		struct {
-			u8 usb_hs_mode;
-		} __packed leaf1;
-		struct {
-			u8 padding;
-		} __packed usbcan1;
-	} __packed;
-	__le16 padding;
-} __packed;
-
-struct leaf_cmd_softinfo {
-	u8 tid;
-	u8 padding0;
-	__le32 sw_options;
-	__le32 fw_version;
-	__le16 max_outstanding_tx;
-	__le16 padding1[9];
-} __packed;
-
-struct usbcan_cmd_softinfo {
-	u8 tid;
-	u8 fw_name[5];
-	__le16 max_outstanding_tx;
-	u8 padding[6];
-	__le32 fw_version;
-	__le16 checksum;
-	__le16 sw_options;
-} __packed;
-
-struct kvaser_cmd_busparams {
-	u8 tid;
-	u8 channel;
-	__le32 bitrate;
-	u8 tseg1;
-	u8 tseg2;
-	u8 sjw;
-	u8 no_samp;
-} __packed;
-
-struct kvaser_cmd_tx_can {
-	u8 channel;
-	u8 tid;
-	u8 data[14];
-	union {
-		struct {
-			u8 padding;
-			u8 flags;
-		} __packed leaf;
-		struct {
-			u8 flags;
-			u8 padding;
-		} __packed usbcan;
-	} __packed;
-} __packed;
-
-struct kvaser_cmd_rx_can_header {
-	u8 channel;
-	u8 flag;
-} __packed;
-
-struct leaf_cmd_rx_can {
-	u8 channel;
-	u8 flag;
-
-	__le16 time[3];
-	u8 data[14];
-} __packed;
-
-struct usbcan_cmd_rx_can {
-	u8 channel;
-	u8 flag;
-
-	u8 data[14];
-	__le16 time;
-} __packed;
-
-struct leaf_cmd_chip_state_event {
-	u8 tid;
-	u8 channel;
-
-	__le16 time[3];
-	u8 tx_errors_count;
-	u8 rx_errors_count;
-
-	u8 status;
-	u8 padding[3];
-} __packed;
-
-struct usbcan_cmd_chip_state_event {
-	u8 tid;
-	u8 channel;
-
-	u8 tx_errors_count;
-	u8 rx_errors_count;
-	__le16 time;
-
-	u8 status;
-	u8 padding[3];
-} __packed;
-
-struct kvaser_cmd_tx_acknowledge_header {
-	u8 channel;
-	u8 tid;
-} __packed;
-
-struct leaf_cmd_error_event {
-	u8 tid;
-	u8 flags;
-	__le16 time[3];
-	u8 channel;
-	u8 padding;
-	u8 tx_errors_count;
-	u8 rx_errors_count;
-	u8 status;
-	u8 error_factor;
-} __packed;
-
-struct usbcan_cmd_error_event {
-	u8 tid;
-	u8 padding;
-	u8 tx_errors_count_ch0;
-	u8 rx_errors_count_ch0;
-	u8 tx_errors_count_ch1;
-	u8 rx_errors_count_ch1;
-	u8 status_ch0;
-	u8 status_ch1;
-	__le16 time;
-} __packed;
-
-struct kvaser_cmd_ctrl_mode {
-	u8 tid;
-	u8 channel;
-	u8 ctrl_mode;
-	u8 padding[3];
-} __packed;
-
-struct kvaser_cmd_flush_queue {
-	u8 tid;
-	u8 channel;
-	u8 flags;
-	u8 padding[3];
-} __packed;
-
-struct leaf_cmd_log_message {
-	u8 channel;
-	u8 flags;
-	__le16 time[3];
-	u8 dlc;
-	u8 time_offset;
-	__le32 id;
-	u8 data[8];
-} __packed;
-
-struct kvaser_cmd {
-	u8 len;
-	u8 id;
-	union	{
-		struct kvaser_cmd_simple simple;
-		struct kvaser_cmd_cardinfo cardinfo;
-		struct kvaser_cmd_busparams busparams;
-
-		struct kvaser_cmd_rx_can_header rx_can_header;
-		struct kvaser_cmd_tx_acknowledge_header tx_acknowledge_header;
-
-		union {
-			struct leaf_cmd_softinfo softinfo;
-			struct leaf_cmd_rx_can rx_can;
-			struct leaf_cmd_chip_state_event chip_state_event;
-			struct leaf_cmd_error_event error_event;
-			struct leaf_cmd_log_message log_message;
-		} __packed leaf;
-
-		union {
-			struct usbcan_cmd_softinfo softinfo;
-			struct usbcan_cmd_rx_can rx_can;
-			struct usbcan_cmd_chip_state_event chip_state_event;
-			struct usbcan_cmd_error_event error_event;
-		} __packed usbcan;
-
-		struct kvaser_cmd_tx_can tx_can;
-		struct kvaser_cmd_ctrl_mode ctrl_mode;
-		struct kvaser_cmd_flush_queue flush_queue;
-	} u;
-} __packed;
-
-/* Summary of a kvaser error event, for a unified Leaf/Usbcan error
- * handling. Some discrepancies between the two families exist:
- *
- * - USBCAN firmware does not report M16C "error factors"
- * - USBCAN controllers has difficulties reporting if the raised error
- *   event is for ch0 or ch1. They leave such arbitration to the OS
- *   driver by letting it compare error counters with previous values
- *   and decide the error event's channel. Thus for USBCAN, the channel
- *   field is only advisory.
- */
-struct kvaser_usb_error_summary {
-	u8 channel, status, txerr, rxerr;
-	union {
-		struct {
-			u8 error_factor;
-		} leaf;
-		struct {
-			u8 other_ch_status;
-			u8 error_state;
-		} usbcan;
-	};
-};
-
-/* Context for an outstanding, not yet ACKed, transmission */
-struct kvaser_usb_tx_urb_context {
-	struct kvaser_usb_net_priv *priv;
-	u32 echo_index;
-	int dlc;
-};
-
-struct kvaser_usb {
-	struct usb_device *udev;
-	struct usb_interface *intf;
-	struct kvaser_usb_net_priv *nets[MAX_NET_DEVICES];
-
-	struct usb_endpoint_descriptor *bulk_in, *bulk_out;
-	struct usb_anchor rx_submitted;
-
-	/* @max_tx_urbs: Firmware-reported maximum number of outstanding,
-	 * not yet ACKed, transmissions on this device. This value is
-	 * also used as a sentinel for marking free tx contexts.
-	 */
-	u32 fw_version;
-	unsigned int nchannels;
-	unsigned int max_tx_urbs;
-	enum kvaser_usb_family family;
-
-	bool rxinitdone;
-	void *rxbuf[MAX_RX_URBS];
-	dma_addr_t rxbuf_dma[MAX_RX_URBS];
-};
-
-struct kvaser_usb_net_priv {
-	struct can_priv can;
-	struct can_berr_counter bec;
-
-	struct kvaser_usb *dev;
-	struct net_device *netdev;
-	int channel;
-
-	struct completion start_comp, stop_comp;
-	struct usb_anchor tx_submitted;
-
-	spinlock_t tx_contexts_lock;
-	int active_tx_contexts;
-	struct kvaser_usb_tx_urb_context tx_contexts[];
-};
-
-static const struct usb_device_id kvaser_usb_table[] = {
-	/* Leaf family IDs */
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_DEVEL_PRODUCT_ID) },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_PRODUCT_ID) },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS |
-			       KVASER_HAS_SILENT_MODE },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_SPRO_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS |
-			       KVASER_HAS_SILENT_MODE },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_LS_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS |
-			       KVASER_HAS_SILENT_MODE },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_SWC_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS |
-			       KVASER_HAS_SILENT_MODE },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_LIN_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS |
-			       KVASER_HAS_SILENT_MODE },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_SPRO_LS_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS |
-			       KVASER_HAS_SILENT_MODE },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_SPRO_SWC_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS |
-			       KVASER_HAS_SILENT_MODE },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MEMO2_DEVEL_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS |
-			       KVASER_HAS_SILENT_MODE },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MEMO2_HSHS_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS |
-			       KVASER_HAS_SILENT_MODE },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_UPRO_HSHS_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_GI_PRODUCT_ID) },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_OBDII_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS |
-			       KVASER_HAS_SILENT_MODE },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MEMO2_HSLS_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_CH_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_BLACKBIRD_SPRO_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_OEM_MERCURY_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_OEM_LEAF_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_CAN_R_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_V2_PRODUCT_ID) },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MINI_PCIE_HS_PRODUCT_ID) },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LIGHT_HS_V2_OEM_PRODUCT_ID) },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_USBCAN_LIGHT_2HS_PRODUCT_ID) },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MINI_PCIE_2HS_PRODUCT_ID) },
-
-	/* USBCANII family IDs */
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_USBCAN2_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_USBCAN_REVB_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MEMORATOR_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS },
-	{ USB_DEVICE(KVASER_VENDOR_ID, USB_VCI2_PRODUCT_ID),
-		.driver_info = KVASER_HAS_TXRX_ERRORS },
-
-	{ }
-};
-MODULE_DEVICE_TABLE(usb, kvaser_usb_table);
-
-static inline int kvaser_usb_send_cmd(const struct kvaser_usb *dev,
-				      struct kvaser_cmd *cmd)
-{
-	int actual_len;
-
-	return usb_bulk_msg(dev->udev,
-			    usb_sndbulkpipe(dev->udev,
-					dev->bulk_out->bEndpointAddress),
-			    cmd, cmd->len, &actual_len, KVASER_USB_TIMEOUT);
-}
-
-static int kvaser_usb_wait_cmd(const struct kvaser_usb *dev, u8 id,
-			       struct kvaser_cmd *cmd)
-{
-	struct kvaser_cmd *tmp;
-	void *buf;
-	int actual_len;
-	int err;
-	int pos;
-	unsigned long to = jiffies + msecs_to_jiffies(KVASER_USB_TIMEOUT);
-
-	buf = kzalloc(RX_BUFFER_SIZE, GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-
-	do {
-		err = usb_bulk_msg(dev->udev,
-				   usb_rcvbulkpipe(dev->udev,
-					dev->bulk_in->bEndpointAddress),
-				   buf, RX_BUFFER_SIZE, &actual_len,
-				   KVASER_USB_TIMEOUT);
-		if (err < 0)
-			goto end;
-
-		pos = 0;
-		while (pos <= actual_len - CMD_HEADER_LEN) {
-			tmp = buf + pos;
-
-			/* Handle commands crossing the USB endpoint max packet
-			 * size boundary. Check kvaser_usb_read_bulk_callback()
-			 * for further details.
-			 */
-			if (tmp->len == 0) {
-				pos = round_up(pos, le16_to_cpu(dev->bulk_in->
-								wMaxPacketSize));
-				continue;
-			}
-
-			if (pos + tmp->len > actual_len) {
-				dev_err_ratelimited(&dev->intf->dev,
-						    "Format error\n");
-				break;
-			}
-
-			if (tmp->id == id) {
-				memcpy(cmd, tmp, tmp->len);
-				goto end;
-			}
-
-			pos += tmp->len;
-		}
-	} while (time_before(jiffies, to));
-
-	err = -EINVAL;
-
-end:
-	kfree(buf);
-
-	return err;
-}
-
-static int kvaser_usb_send_simple_cmd(const struct kvaser_usb *dev,
-				      u8 cmd_id, int channel)
-{
-	struct kvaser_cmd *cmd;
-	int rc;
-
-	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
-	if (!cmd)
-		return -ENOMEM;
-
-	cmd->id = cmd_id;
-	cmd->len = CMD_HEADER_LEN + sizeof(struct kvaser_cmd_simple);
-	cmd->u.simple.channel = channel;
-	cmd->u.simple.tid = 0xff;
-
-	rc = kvaser_usb_send_cmd(dev, cmd);
-
-	kfree(cmd);
-	return rc;
-}
-
-static int kvaser_usb_get_software_info(struct kvaser_usb *dev)
-{
-	struct kvaser_cmd cmd;
-	int err;
-
-	err = kvaser_usb_send_simple_cmd(dev, CMD_GET_SOFTWARE_INFO, 0);
-	if (err)
-		return err;
-
-	err = kvaser_usb_wait_cmd(dev, CMD_GET_SOFTWARE_INFO_REPLY, &cmd);
-	if (err)
-		return err;
-
-	switch (dev->family) {
-	case KVASER_LEAF:
-		dev->fw_version = le32_to_cpu(cmd.u.leaf.softinfo.fw_version);
-		dev->max_tx_urbs =
-			le16_to_cpu(cmd.u.leaf.softinfo.max_outstanding_tx);
-		break;
-	case KVASER_USBCAN:
-		dev->fw_version = le32_to_cpu(cmd.u.usbcan.softinfo.fw_version);
-		dev->max_tx_urbs =
-			le16_to_cpu(cmd.u.usbcan.softinfo.max_outstanding_tx);
-		break;
-	}
-
-	return 0;
-}
-
-static int kvaser_usb_get_card_info(struct kvaser_usb *dev)
-{
-	struct kvaser_cmd cmd;
-	int err;
-
-	err = kvaser_usb_send_simple_cmd(dev, CMD_GET_CARD_INFO, 0);
-	if (err)
-		return err;
-
-	err = kvaser_usb_wait_cmd(dev, CMD_GET_CARD_INFO_REPLY, &cmd);
-	if (err)
-		return err;
-
-	dev->nchannels = cmd.u.cardinfo.nchannels;
-	if ((dev->nchannels > MAX_NET_DEVICES) ||
-	    (dev->family == KVASER_USBCAN &&
-	     dev->nchannels > MAX_USBCAN_NET_DEVICES))
-		return -EINVAL;
-
-	return 0;
-}
-
-static void kvaser_usb_tx_acknowledge(const struct kvaser_usb *dev,
-				      const struct kvaser_cmd *cmd)
-{
-	struct net_device_stats *stats;
-	struct kvaser_usb_tx_urb_context *context;
-	struct kvaser_usb_net_priv *priv;
-	struct sk_buff *skb;
-	struct can_frame *cf;
-	unsigned long flags;
-	u8 channel, tid;
-
-	channel = cmd->u.tx_acknowledge_header.channel;
-	tid = cmd->u.tx_acknowledge_header.tid;
-
-	if (channel >= dev->nchannels) {
-		dev_err(&dev->intf->dev,
-			"Invalid channel number (%d)\n", channel);
-		return;
-	}
-
-	priv = dev->nets[channel];
-
-	if (!netif_device_present(priv->netdev))
-		return;
-
-	stats = &priv->netdev->stats;
-
-	context = &priv->tx_contexts[tid % dev->max_tx_urbs];
-
-	/* Sometimes the state change doesn't come after a bus-off event */
-	if (priv->can.restart_ms &&
-	    (priv->can.state >= CAN_STATE_BUS_OFF)) {
-		skb = alloc_can_err_skb(priv->netdev, &cf);
-		if (skb) {
-			cf->can_id |= CAN_ERR_RESTARTED;
-
-			stats->rx_packets++;
-			stats->rx_bytes += cf->can_dlc;
-			netif_rx(skb);
-		} else {
-			netdev_err(priv->netdev,
-				   "No memory left for err_skb\n");
-		}
-
-		priv->can.can_stats.restarts++;
-		netif_carrier_on(priv->netdev);
-
-		priv->can.state = CAN_STATE_ERROR_ACTIVE;
-	}
-
-	stats->tx_packets++;
-	stats->tx_bytes += context->dlc;
-
-	spin_lock_irqsave(&priv->tx_contexts_lock, flags);
-
-	can_get_echo_skb(priv->netdev, context->echo_index);
-	context->echo_index = dev->max_tx_urbs;
-	--priv->active_tx_contexts;
-	netif_wake_queue(priv->netdev);
-
-	spin_unlock_irqrestore(&priv->tx_contexts_lock, flags);
-}
-
-static void kvaser_usb_simple_cmd_callback(struct urb *urb)
-{
-	struct net_device *netdev = urb->context;
-
-	kfree(urb->transfer_buffer);
-
-	if (urb->status)
-		netdev_warn(netdev, "urb status received: %d\n",
-			    urb->status);
-}
-
-static int kvaser_usb_simple_cmd_async(struct kvaser_usb_net_priv *priv,
-				       u8 cmd_id)
-{
-	struct kvaser_usb *dev = priv->dev;
-	struct net_device *netdev = priv->netdev;
-	struct kvaser_cmd *cmd;
-	struct urb *urb;
-	void *buf;
-	int err;
-
-	urb = usb_alloc_urb(0, GFP_ATOMIC);
-	if (!urb)
-		return -ENOMEM;
-
-	buf = kmalloc(sizeof(struct kvaser_cmd), GFP_ATOMIC);
-	if (!buf) {
-		usb_free_urb(urb);
-		return -ENOMEM;
-	}
-
-	cmd = (struct kvaser_cmd *)buf;
-	cmd->len = CMD_HEADER_LEN + sizeof(struct kvaser_cmd_simple);
-	cmd->id = cmd_id;
-	cmd->u.simple.channel = priv->channel;
-
-	usb_fill_bulk_urb(urb, dev->udev,
-			  usb_sndbulkpipe(dev->udev,
-					  dev->bulk_out->bEndpointAddress),
-			  buf, cmd->len,
-			  kvaser_usb_simple_cmd_callback, netdev);
-	usb_anchor_urb(urb, &priv->tx_submitted);
-
-	err = usb_submit_urb(urb, GFP_ATOMIC);
-	if (err) {
-		netdev_err(netdev, "Error transmitting URB\n");
-		usb_unanchor_urb(urb);
-		kfree(buf);
-		usb_free_urb(urb);
-		return err;
-	}
-
-	usb_free_urb(urb);
-
-	return 0;
-}
-
-static void kvaser_usb_rx_error_update_can_state(struct kvaser_usb_net_priv *priv,
-						 const struct kvaser_usb_error_summary *es,
-						 struct can_frame *cf)
-{
-	struct kvaser_usb *dev = priv->dev;
-	struct net_device_stats *stats = &priv->netdev->stats;
-	enum can_state cur_state, new_state, tx_state, rx_state;
-
-	netdev_dbg(priv->netdev, "Error status: 0x%02x\n", es->status);
-
-	new_state = cur_state = priv->can.state;
-
-	if (es->status & (M16C_STATE_BUS_OFF | M16C_STATE_BUS_RESET))
-		new_state = CAN_STATE_BUS_OFF;
-	else if (es->status & M16C_STATE_BUS_PASSIVE)
-		new_state = CAN_STATE_ERROR_PASSIVE;
-	else if (es->status & M16C_STATE_BUS_ERROR) {
-		/* Guard against spurious error events after a busoff */
-		if (cur_state < CAN_STATE_BUS_OFF) {
-			if ((es->txerr >= 128) || (es->rxerr >= 128))
-				new_state = CAN_STATE_ERROR_PASSIVE;
-			else if ((es->txerr >= 96) || (es->rxerr >= 96))
-				new_state = CAN_STATE_ERROR_WARNING;
-			else if (cur_state > CAN_STATE_ERROR_ACTIVE)
-				new_state = CAN_STATE_ERROR_ACTIVE;
-		}
-	}
-
-	if (!es->status)
-		new_state = CAN_STATE_ERROR_ACTIVE;
-
-	if (new_state != cur_state) {
-		tx_state = (es->txerr >= es->rxerr) ? new_state : 0;
-		rx_state = (es->txerr <= es->rxerr) ? new_state : 0;
-
-		can_change_state(priv->netdev, cf, tx_state, rx_state);
-	}
-
-	if (priv->can.restart_ms &&
-	    (cur_state >= CAN_STATE_BUS_OFF) &&
-	    (new_state < CAN_STATE_BUS_OFF)) {
-		priv->can.can_stats.restarts++;
-	}
-
-	switch (dev->family) {
-	case KVASER_LEAF:
-		if (es->leaf.error_factor) {
-			priv->can.can_stats.bus_error++;
-			stats->rx_errors++;
-		}
-		break;
-	case KVASER_USBCAN:
-		if (es->usbcan.error_state & USBCAN_ERROR_STATE_TX_ERROR)
-			stats->tx_errors++;
-		if (es->usbcan.error_state & USBCAN_ERROR_STATE_RX_ERROR)
-			stats->rx_errors++;
-		if (es->usbcan.error_state & USBCAN_ERROR_STATE_BUSERROR) {
-			priv->can.can_stats.bus_error++;
-		}
-		break;
-	}
-
-	priv->bec.txerr = es->txerr;
-	priv->bec.rxerr = es->rxerr;
-}
-
-static void kvaser_usb_rx_error(const struct kvaser_usb *dev,
-				const struct kvaser_usb_error_summary *es)
-{
-	struct can_frame *cf, tmp_cf = { .can_id = CAN_ERR_FLAG, .can_dlc = CAN_ERR_DLC };
-	struct sk_buff *skb;
-	struct net_device_stats *stats;
-	struct kvaser_usb_net_priv *priv;
-	enum can_state old_state, new_state;
-
-	if (es->channel >= dev->nchannels) {
-		dev_err(&dev->intf->dev,
-			"Invalid channel number (%d)\n", es->channel);
-		return;
-	}
-
-	priv = dev->nets[es->channel];
-	stats = &priv->netdev->stats;
-
-	/* Update all of the CAN interface's state and error counters before
-	 * trying any memory allocation that can actually fail with -ENOMEM.
-	 *
-	 * We send a temporary stack-allocated error CAN frame to
-	 * can_change_state() for the very same reason.
-	 *
-	 * TODO: Split can_change_state() responsibility between updating the
-	 * CAN interface's state and counters, and the setting up of CAN error
-	 * frame ID and data to userspace. Remove stack allocation afterwards.
-	 */
-	old_state = priv->can.state;
-	kvaser_usb_rx_error_update_can_state(priv, es, &tmp_cf);
-	new_state = priv->can.state;
-
-	skb = alloc_can_err_skb(priv->netdev, &cf);
-	if (!skb) {
-		stats->rx_dropped++;
-		return;
-	}
-	memcpy(cf, &tmp_cf, sizeof(*cf));
-
-	if (new_state != old_state) {
-		if (es->status &
-		    (M16C_STATE_BUS_OFF | M16C_STATE_BUS_RESET)) {
-			if (!priv->can.restart_ms)
-				kvaser_usb_simple_cmd_async(priv, CMD_STOP_CHIP);
-			netif_carrier_off(priv->netdev);
-		}
-
-		if (priv->can.restart_ms &&
-		    (old_state >= CAN_STATE_BUS_OFF) &&
-		    (new_state < CAN_STATE_BUS_OFF)) {
-			cf->can_id |= CAN_ERR_RESTARTED;
-			netif_carrier_on(priv->netdev);
-		}
-	}
-
-	switch (dev->family) {
-	case KVASER_LEAF:
-		if (es->leaf.error_factor) {
-			cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_PROT;
-
-			if (es->leaf.error_factor & M16C_EF_ACKE)
-				cf->data[3] = CAN_ERR_PROT_LOC_ACK;
-			if (es->leaf.error_factor & M16C_EF_CRCE)
-				cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
-			if (es->leaf.error_factor & M16C_EF_FORME)
-				cf->data[2] |= CAN_ERR_PROT_FORM;
-			if (es->leaf.error_factor & M16C_EF_STFE)
-				cf->data[2] |= CAN_ERR_PROT_STUFF;
-			if (es->leaf.error_factor & M16C_EF_BITE0)
-				cf->data[2] |= CAN_ERR_PROT_BIT0;
-			if (es->leaf.error_factor & M16C_EF_BITE1)
-				cf->data[2] |= CAN_ERR_PROT_BIT1;
-			if (es->leaf.error_factor & M16C_EF_TRE)
-				cf->data[2] |= CAN_ERR_PROT_TX;
-		}
-		break;
-	case KVASER_USBCAN:
-		if (es->usbcan.error_state & USBCAN_ERROR_STATE_BUSERROR) {
-			cf->can_id |= CAN_ERR_BUSERROR;
-		}
-		break;
-	}
-
-	cf->data[6] = es->txerr;
-	cf->data[7] = es->rxerr;
-
-	stats->rx_packets++;
-	stats->rx_bytes += cf->can_dlc;
-	netif_rx(skb);
-}
-
-/* For USBCAN, report error to userspace if the channels's errors counter
- * has changed, or we're the only channel seeing a bus error state.
- */
-static void kvaser_usbcan_conditionally_rx_error(const struct kvaser_usb *dev,
-						 struct kvaser_usb_error_summary *es)
-{
-	struct kvaser_usb_net_priv *priv;
-	int channel;
-	bool report_error;
-
-	channel = es->channel;
-	if (channel >= dev->nchannels) {
-		dev_err(&dev->intf->dev,
-			"Invalid channel number (%d)\n", channel);
-		return;
-	}
-
-	priv = dev->nets[channel];
-	report_error = false;
-
-	if (es->txerr != priv->bec.txerr) {
-		es->usbcan.error_state |= USBCAN_ERROR_STATE_TX_ERROR;
-		report_error = true;
-	}
-	if (es->rxerr != priv->bec.rxerr) {
-		es->usbcan.error_state |= USBCAN_ERROR_STATE_RX_ERROR;
-		report_error = true;
-	}
-	if ((es->status & M16C_STATE_BUS_ERROR) &&
-	    !(es->usbcan.other_ch_status & M16C_STATE_BUS_ERROR)) {
-		es->usbcan.error_state |= USBCAN_ERROR_STATE_BUSERROR;
-		report_error = true;
-	}
-
-	if (report_error)
-		kvaser_usb_rx_error(dev, es);
-}
-
-static void kvaser_usbcan_rx_error(const struct kvaser_usb *dev,
-				   const struct kvaser_cmd *cmd)
-{
-	struct kvaser_usb_error_summary es = { };
-
-	switch (cmd->id) {
-	/* Sometimes errors are sent as unsolicited chip state events */
-	case CMD_CHIP_STATE_EVENT:
-		es.channel = cmd->u.usbcan.chip_state_event.channel;
-		es.status =  cmd->u.usbcan.chip_state_event.status;
-		es.txerr = cmd->u.usbcan.chip_state_event.tx_errors_count;
-		es.rxerr = cmd->u.usbcan.chip_state_event.rx_errors_count;
-		kvaser_usbcan_conditionally_rx_error(dev, &es);
-		break;
-
-	case CMD_CAN_ERROR_EVENT:
-		es.channel = 0;
-		es.status = cmd->u.usbcan.error_event.status_ch0;
-		es.txerr = cmd->u.usbcan.error_event.tx_errors_count_ch0;
-		es.rxerr = cmd->u.usbcan.error_event.rx_errors_count_ch0;
-		es.usbcan.other_ch_status =
-			cmd->u.usbcan.error_event.status_ch1;
-		kvaser_usbcan_conditionally_rx_error(dev, &es);
-
-		/* The USBCAN firmware supports up to 2 channels.
-		 * Now that ch0 was checked, check if ch1 has any errors.
-		 */
-		if (dev->nchannels == MAX_USBCAN_NET_DEVICES) {
-			es.channel = 1;
-			es.status = cmd->u.usbcan.error_event.status_ch1;
-			es.txerr = cmd->u.usbcan.error_event.tx_errors_count_ch1;
-			es.rxerr = cmd->u.usbcan.error_event.rx_errors_count_ch1;
-			es.usbcan.other_ch_status =
-				cmd->u.usbcan.error_event.status_ch0;
-			kvaser_usbcan_conditionally_rx_error(dev, &es);
-		}
-		break;
-
-	default:
-		dev_err(&dev->intf->dev, "Invalid cmd id (%d)\n", cmd->id);
-	}
-}
-
-static void kvaser_leaf_rx_error(const struct kvaser_usb *dev,
-				 const struct kvaser_cmd *cmd)
-{
-	struct kvaser_usb_error_summary es = { };
-
-	switch (cmd->id) {
-	case CMD_CAN_ERROR_EVENT:
-		es.channel = cmd->u.leaf.error_event.channel;
-		es.status =  cmd->u.leaf.error_event.status;
-		es.txerr = cmd->u.leaf.error_event.tx_errors_count;
-		es.rxerr = cmd->u.leaf.error_event.rx_errors_count;
-		es.leaf.error_factor = cmd->u.leaf.error_event.error_factor;
-		break;
-	case CMD_LEAF_LOG_MESSAGE:
-		es.channel = cmd->u.leaf.log_message.channel;
-		es.status = cmd->u.leaf.log_message.data[0];
-		es.txerr = cmd->u.leaf.log_message.data[2];
-		es.rxerr = cmd->u.leaf.log_message.data[3];
-		es.leaf.error_factor = cmd->u.leaf.log_message.data[1];
-		break;
-	case CMD_CHIP_STATE_EVENT:
-		es.channel = cmd->u.leaf.chip_state_event.channel;
-		es.status =  cmd->u.leaf.chip_state_event.status;
-		es.txerr = cmd->u.leaf.chip_state_event.tx_errors_count;
-		es.rxerr = cmd->u.leaf.chip_state_event.rx_errors_count;
-		es.leaf.error_factor = 0;
-		break;
-	default:
-		dev_err(&dev->intf->dev, "Invalid cmd id (%d)\n", cmd->id);
-		return;
-	}
-
-	kvaser_usb_rx_error(dev, &es);
-}
-
-static void kvaser_usb_rx_can_err(const struct kvaser_usb_net_priv *priv,
-				  const struct kvaser_cmd *cmd)
-{
-	struct can_frame *cf;
-	struct sk_buff *skb;
-	struct net_device_stats *stats = &priv->netdev->stats;
-
-	if (cmd->u.rx_can_header.flag & (MSG_FLAG_ERROR_FRAME |
-					 MSG_FLAG_NERR)) {
-		netdev_err(priv->netdev, "Unknown error (flags: 0x%02x)\n",
-			   cmd->u.rx_can_header.flag);
-
-		stats->rx_errors++;
-		return;
-	}
-
-	if (cmd->u.rx_can_header.flag & MSG_FLAG_OVERRUN) {
-		stats->rx_over_errors++;
-		stats->rx_errors++;
-
-		skb = alloc_can_err_skb(priv->netdev, &cf);
-		if (!skb) {
-			stats->rx_dropped++;
-			return;
-		}
-
-		cf->can_id |= CAN_ERR_CRTL;
-		cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
-
-		stats->rx_packets++;
-		stats->rx_bytes += cf->can_dlc;
-		netif_rx(skb);
-	}
-}
-
-static void kvaser_usb_rx_can_msg(const struct kvaser_usb *dev,
-				  const struct kvaser_cmd *cmd)
-{
-	struct kvaser_usb_net_priv *priv;
-	struct can_frame *cf;
-	struct sk_buff *skb;
-	struct net_device_stats *stats;
-	u8 channel = cmd->u.rx_can_header.channel;
-	const u8 *rx_data = NULL;	/* GCC */
-
-	if (channel >= dev->nchannels) {
-		dev_err(&dev->intf->dev,
-			"Invalid channel number (%d)\n", channel);
-		return;
-	}
-
-	priv = dev->nets[channel];
-	stats = &priv->netdev->stats;
-
-	if ((cmd->u.rx_can_header.flag & MSG_FLAG_ERROR_FRAME) &&
-	    (dev->family == KVASER_LEAF && cmd->id == CMD_LEAF_LOG_MESSAGE)) {
-		kvaser_leaf_rx_error(dev, cmd);
-		return;
-	} else if (cmd->u.rx_can_header.flag & (MSG_FLAG_ERROR_FRAME |
-						MSG_FLAG_NERR |
-						MSG_FLAG_OVERRUN)) {
-		kvaser_usb_rx_can_err(priv, cmd);
-		return;
-	} else if (cmd->u.rx_can_header.flag & ~MSG_FLAG_REMOTE_FRAME) {
-		netdev_warn(priv->netdev,
-			    "Unhandled frame (flags: 0x%02x)",
-			    cmd->u.rx_can_header.flag);
-		return;
-	}
-
-	switch (dev->family) {
-	case KVASER_LEAF:
-		rx_data = cmd->u.leaf.rx_can.data;
-		break;
-	case KVASER_USBCAN:
-		rx_data = cmd->u.usbcan.rx_can.data;
-		break;
-	}
-
-	skb = alloc_can_skb(priv->netdev, &cf);
-	if (!skb) {
-		stats->rx_dropped++;
-		return;
-	}
-
-	if (dev->family == KVASER_LEAF && cmd->id == CMD_LEAF_LOG_MESSAGE) {
-		cf->can_id = le32_to_cpu(cmd->u.leaf.log_message.id);
-		if (cf->can_id & KVASER_EXTENDED_FRAME)
-			cf->can_id &= CAN_EFF_MASK | CAN_EFF_FLAG;
-		else
-			cf->can_id &= CAN_SFF_MASK;
-
-		cf->can_dlc = get_can_dlc(cmd->u.leaf.log_message.dlc);
-
-		if (cmd->u.leaf.log_message.flags & MSG_FLAG_REMOTE_FRAME)
-			cf->can_id |= CAN_RTR_FLAG;
-		else
-			memcpy(cf->data, &cmd->u.leaf.log_message.data,
-			       cf->can_dlc);
-	} else {
-		cf->can_id = ((rx_data[0] & 0x1f) << 6) | (rx_data[1] & 0x3f);
-
-		if (cmd->id == CMD_RX_EXT_MESSAGE) {
-			cf->can_id <<= 18;
-			cf->can_id |= ((rx_data[2] & 0x0f) << 14) |
-				      ((rx_data[3] & 0xff) << 6) |
-				      (rx_data[4] & 0x3f);
-			cf->can_id |= CAN_EFF_FLAG;
-		}
-
-		cf->can_dlc = get_can_dlc(rx_data[5]);
-
-		if (cmd->u.rx_can_header.flag & MSG_FLAG_REMOTE_FRAME)
-			cf->can_id |= CAN_RTR_FLAG;
-		else
-			memcpy(cf->data, &rx_data[6], cf->can_dlc);
-	}
-
-	stats->rx_packets++;
-	stats->rx_bytes += cf->can_dlc;
-	netif_rx(skb);
-}
-
-static void kvaser_usb_start_chip_reply(const struct kvaser_usb *dev,
-					const struct kvaser_cmd *cmd)
-{
-	struct kvaser_usb_net_priv *priv;
-	u8 channel = cmd->u.simple.channel;
-
-	if (channel >= dev->nchannels) {
-		dev_err(&dev->intf->dev,
-			"Invalid channel number (%d)\n", channel);
-		return;
-	}
-
-	priv = dev->nets[channel];
-
-	if (completion_done(&priv->start_comp) &&
-	    netif_queue_stopped(priv->netdev)) {
-		netif_wake_queue(priv->netdev);
-	} else {
-		netif_start_queue(priv->netdev);
-		complete(&priv->start_comp);
-	}
-}
-
-static void kvaser_usb_stop_chip_reply(const struct kvaser_usb *dev,
-				       const struct kvaser_cmd *cmd)
-{
-	struct kvaser_usb_net_priv *priv;
-	u8 channel = cmd->u.simple.channel;
-
-	if (channel >= dev->nchannels) {
-		dev_err(&dev->intf->dev,
-			"Invalid channel number (%d)\n", channel);
-		return;
-	}
-
-	priv = dev->nets[channel];
-
-	complete(&priv->stop_comp);
-}
-
-static void kvaser_usb_handle_cmd(const struct kvaser_usb *dev,
-				  const struct kvaser_cmd *cmd)
-{
-	switch (cmd->id) {
-	case CMD_START_CHIP_REPLY:
-		kvaser_usb_start_chip_reply(dev, cmd);
-		break;
-
-	case CMD_STOP_CHIP_REPLY:
-		kvaser_usb_stop_chip_reply(dev, cmd);
-		break;
-
-	case CMD_RX_STD_MESSAGE:
-	case CMD_RX_EXT_MESSAGE:
-		kvaser_usb_rx_can_msg(dev, cmd);
-		break;
-
-	case CMD_LEAF_LOG_MESSAGE:
-		if (dev->family != KVASER_LEAF)
-			goto warn;
-		kvaser_usb_rx_can_msg(dev, cmd);
-		break;
-
-	case CMD_CHIP_STATE_EVENT:
-	case CMD_CAN_ERROR_EVENT:
-		if (dev->family == KVASER_LEAF)
-			kvaser_leaf_rx_error(dev, cmd);
-		else
-			kvaser_usbcan_rx_error(dev, cmd);
-		break;
-
-	case CMD_TX_ACKNOWLEDGE:
-		kvaser_usb_tx_acknowledge(dev, cmd);
-		break;
-
-	/* Ignored commands */
-	case CMD_USBCAN_CLOCK_OVERFLOW_EVENT:
-		if (dev->family != KVASER_USBCAN)
-			goto warn;
-		break;
-
-	case CMD_FLUSH_QUEUE_REPLY:
-		if (dev->family != KVASER_LEAF)
-			goto warn;
-		break;
-
-	default:
-warn:		dev_warn(&dev->intf->dev, "Unhandled command (%d)\n", cmd->id);
-		break;
-	}
-}
-
-static void kvaser_usb_read_bulk_callback(struct urb *urb)
-{
-	struct kvaser_usb *dev = urb->context;
-	struct kvaser_cmd *cmd;
-	int pos = 0;
-	int err, i;
-
-	switch (urb->status) {
-	case 0:
-		break;
-	case -ENOENT:
-	case -EPIPE:
-	case -EPROTO:
-	case -ESHUTDOWN:
-		return;
-	default:
-		dev_info(&dev->intf->dev, "Rx URB aborted (%d)\n", urb->status);
-		goto resubmit_urb;
-	}
-
-	while (pos <= (int)(urb->actual_length - CMD_HEADER_LEN)) {
-		cmd = urb->transfer_buffer + pos;
-
-		/* The Kvaser firmware can only read and write commands that
-		 * does not cross the USB's endpoint wMaxPacketSize boundary.
-		 * If a follow-up command crosses such boundary, firmware puts
-		 * a placeholder zero-length command in its place then aligns
-		 * the real command to the next max packet size.
-		 *
-		 * Handle such cases or we're going to miss a significant
-		 * number of events in case of a heavy rx load on the bus.
-		 */
-		if (cmd->len == 0) {
-			pos = round_up(pos, le16_to_cpu(dev->bulk_in->
-							wMaxPacketSize));
-			continue;
-		}
-
-		if (pos + cmd->len > urb->actual_length) {
-			dev_err_ratelimited(&dev->intf->dev, "Format error\n");
-			break;
-		}
-
-		kvaser_usb_handle_cmd(dev, cmd);
-		pos += cmd->len;
-	}
-
-resubmit_urb:
-	usb_fill_bulk_urb(urb, dev->udev,
-			  usb_rcvbulkpipe(dev->udev,
-					  dev->bulk_in->bEndpointAddress),
-			  urb->transfer_buffer, RX_BUFFER_SIZE,
-			  kvaser_usb_read_bulk_callback, dev);
-
-	err = usb_submit_urb(urb, GFP_ATOMIC);
-	if (err == -ENODEV) {
-		for (i = 0; i < dev->nchannels; i++) {
-			if (!dev->nets[i])
-				continue;
-
-			netif_device_detach(dev->nets[i]->netdev);
-		}
-	} else if (err) {
-		dev_err(&dev->intf->dev,
-			"Failed resubmitting read bulk urb: %d\n", err);
-	}
-}
-
-static int kvaser_usb_setup_rx_urbs(struct kvaser_usb *dev)
-{
-	int i, err = 0;
-
-	if (dev->rxinitdone)
-		return 0;
-
-	for (i = 0; i < MAX_RX_URBS; i++) {
-		struct urb *urb = NULL;
-		u8 *buf = NULL;
-		dma_addr_t buf_dma;
-
-		urb = usb_alloc_urb(0, GFP_KERNEL);
-		if (!urb) {
-			err = -ENOMEM;
-			break;
-		}
-
-		buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE,
-					 GFP_KERNEL, &buf_dma);
-		if (!buf) {
-			dev_warn(&dev->intf->dev,
-				 "No memory left for USB buffer\n");
-			usb_free_urb(urb);
-			err = -ENOMEM;
-			break;
-		}
-
-		usb_fill_bulk_urb(urb, dev->udev,
-				  usb_rcvbulkpipe(dev->udev,
-					  dev->bulk_in->bEndpointAddress),
-				  buf, RX_BUFFER_SIZE,
-				  kvaser_usb_read_bulk_callback,
-				  dev);
-		urb->transfer_dma = buf_dma;
-		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
-		usb_anchor_urb(urb, &dev->rx_submitted);
-
-		err = usb_submit_urb(urb, GFP_KERNEL);
-		if (err) {
-			usb_unanchor_urb(urb);
-			usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
-					  buf_dma);
-			usb_free_urb(urb);
-			break;
-		}
-
-		dev->rxbuf[i] = buf;
-		dev->rxbuf_dma[i] = buf_dma;
-
-		usb_free_urb(urb);
-	}
-
-	if (i == 0) {
-		dev_warn(&dev->intf->dev, "Cannot setup read URBs, error %d\n",
-			 err);
-		return err;
-	} else if (i < MAX_RX_URBS) {
-		dev_warn(&dev->intf->dev, "RX performances may be slow\n");
-	}
-
-	dev->rxinitdone = true;
-
-	return 0;
-}
-
-static int kvaser_usb_set_opt_mode(const struct kvaser_usb_net_priv *priv)
-{
-	struct kvaser_cmd *cmd;
-	int rc;
-
-	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
-	if (!cmd)
-		return -ENOMEM;
-
-	cmd->id = CMD_SET_CTRL_MODE;
-	cmd->len = CMD_HEADER_LEN + sizeof(struct kvaser_cmd_ctrl_mode);
-	cmd->u.ctrl_mode.tid = 0xff;
-	cmd->u.ctrl_mode.channel = priv->channel;
-
-	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
-		cmd->u.ctrl_mode.ctrl_mode = KVASER_CTRL_MODE_SILENT;
-	else
-		cmd->u.ctrl_mode.ctrl_mode = KVASER_CTRL_MODE_NORMAL;
-
-	rc = kvaser_usb_send_cmd(priv->dev, cmd);
-
-	kfree(cmd);
-	return rc;
-}
-
-static int kvaser_usb_start_chip(struct kvaser_usb_net_priv *priv)
-{
-	int err;
-
-	init_completion(&priv->start_comp);
-
-	err = kvaser_usb_send_simple_cmd(priv->dev, CMD_START_CHIP,
-					 priv->channel);
-	if (err)
-		return err;
-
-	if (!wait_for_completion_timeout(&priv->start_comp,
-					 msecs_to_jiffies(KVASER_USB_TIMEOUT)))
-		return -ETIMEDOUT;
-
-	return 0;
-}
-
-static int kvaser_usb_open(struct net_device *netdev)
-{
-	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
-	struct kvaser_usb *dev = priv->dev;
-	int err;
-
-	err = open_candev(netdev);
-	if (err)
-		return err;
-
-	err = kvaser_usb_setup_rx_urbs(dev);
-	if (err)
-		goto error;
-
-	err = kvaser_usb_set_opt_mode(priv);
-	if (err)
-		goto error;
-
-	err = kvaser_usb_start_chip(priv);
-	if (err) {
-		netdev_warn(netdev, "Cannot start device, error %d\n", err);
-		goto error;
-	}
-
-	priv->can.state = CAN_STATE_ERROR_ACTIVE;
-
-	return 0;
-
-error:
-	close_candev(netdev);
-	return err;
-}
-
-static void kvaser_usb_reset_tx_urb_contexts(struct kvaser_usb_net_priv *priv)
-{
-	int i, max_tx_urbs;
-
-	max_tx_urbs = priv->dev->max_tx_urbs;
-
-	priv->active_tx_contexts = 0;
-	for (i = 0; i < max_tx_urbs; i++)
-		priv->tx_contexts[i].echo_index = max_tx_urbs;
-}
-
-/* This method might sleep. Do not call it in the atomic context
- * of URB completions.
- */
-static void kvaser_usb_unlink_tx_urbs(struct kvaser_usb_net_priv *priv)
-{
-	usb_kill_anchored_urbs(&priv->tx_submitted);
-	kvaser_usb_reset_tx_urb_contexts(priv);
-}
-
-static void kvaser_usb_unlink_all_urbs(struct kvaser_usb *dev)
-{
-	int i;
-
-	usb_kill_anchored_urbs(&dev->rx_submitted);
-
-	for (i = 0; i < MAX_RX_URBS; i++)
-		usb_free_coherent(dev->udev, RX_BUFFER_SIZE,
-				  dev->rxbuf[i],
-				  dev->rxbuf_dma[i]);
-
-	for (i = 0; i < dev->nchannels; i++) {
-		struct kvaser_usb_net_priv *priv = dev->nets[i];
-
-		if (priv)
-			kvaser_usb_unlink_tx_urbs(priv);
-	}
-}
-
-static int kvaser_usb_stop_chip(struct kvaser_usb_net_priv *priv)
-{
-	int err;
-
-	init_completion(&priv->stop_comp);
-
-	err = kvaser_usb_send_simple_cmd(priv->dev, CMD_STOP_CHIP,
-					 priv->channel);
-	if (err)
-		return err;
-
-	if (!wait_for_completion_timeout(&priv->stop_comp,
-					 msecs_to_jiffies(KVASER_USB_TIMEOUT)))
-		return -ETIMEDOUT;
-
-	return 0;
-}
-
-static int kvaser_usb_flush_queue(struct kvaser_usb_net_priv *priv)
-{
-	struct kvaser_cmd *cmd;
-	int rc;
-
-	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
-	if (!cmd)
-		return -ENOMEM;
-
-	cmd->id = CMD_FLUSH_QUEUE;
-	cmd->len = CMD_HEADER_LEN + sizeof(struct kvaser_cmd_flush_queue);
-	cmd->u.flush_queue.channel = priv->channel;
-	cmd->u.flush_queue.flags = 0x00;
-
-	rc = kvaser_usb_send_cmd(priv->dev, cmd);
-
-	kfree(cmd);
-	return rc;
-}
-
-static int kvaser_usb_close(struct net_device *netdev)
-{
-	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
-	struct kvaser_usb *dev = priv->dev;
-	int err;
-
-	netif_stop_queue(netdev);
-
-	err = kvaser_usb_flush_queue(priv);
-	if (err)
-		netdev_warn(netdev, "Cannot flush queue, error %d\n", err);
-
-	err = kvaser_usb_send_simple_cmd(dev, CMD_RESET_CHIP, priv->channel);
-	if (err)
-		netdev_warn(netdev, "Cannot reset card, error %d\n", err);
-
-	err = kvaser_usb_stop_chip(priv);
-	if (err)
-		netdev_warn(netdev, "Cannot stop device, error %d\n", err);
-
-	/* reset tx contexts */
-	kvaser_usb_unlink_tx_urbs(priv);
-
-	priv->can.state = CAN_STATE_STOPPED;
-	close_candev(priv->netdev);
-
-	return 0;
-}
-
-static void kvaser_usb_write_bulk_callback(struct urb *urb)
-{
-	struct kvaser_usb_tx_urb_context *context = urb->context;
-	struct kvaser_usb_net_priv *priv;
-	struct net_device *netdev;
-
-	if (WARN_ON(!context))
-		return;
-
-	priv = context->priv;
-	netdev = priv->netdev;
-
-	kfree(urb->transfer_buffer);
-
-	if (!netif_device_present(netdev))
-		return;
-
-	if (urb->status)
-		netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
-}
-
-static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb,
-					 struct net_device *netdev)
-{
-	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
-	struct kvaser_usb *dev = priv->dev;
-	struct net_device_stats *stats = &netdev->stats;
-	struct can_frame *cf = (struct can_frame *)skb->data;
-	struct kvaser_usb_tx_urb_context *context = NULL;
-	struct urb *urb;
-	void *buf;
-	struct kvaser_cmd *cmd;
-	int i, err, ret = NETDEV_TX_OK;
-	u8 *cmd_tx_can_flags = NULL;		/* GCC */
-	unsigned long flags;
-
-	if (can_dropped_invalid_skb(netdev, skb))
-		return NETDEV_TX_OK;
-
-	urb = usb_alloc_urb(0, GFP_ATOMIC);
-	if (!urb) {
-		stats->tx_dropped++;
-		dev_kfree_skb(skb);
-		return NETDEV_TX_OK;
-	}
-
-	buf = kmalloc(sizeof(struct kvaser_cmd), GFP_ATOMIC);
-	if (!buf) {
-		stats->tx_dropped++;
-		dev_kfree_skb(skb);
-		goto freeurb;
-	}
-
-	cmd = buf;
-	cmd->len = CMD_HEADER_LEN + sizeof(struct kvaser_cmd_tx_can);
-	cmd->u.tx_can.channel = priv->channel;
-
-	switch (dev->family) {
-	case KVASER_LEAF:
-		cmd_tx_can_flags = &cmd->u.tx_can.leaf.flags;
-		break;
-	case KVASER_USBCAN:
-		cmd_tx_can_flags = &cmd->u.tx_can.usbcan.flags;
-		break;
-	}
-
-	*cmd_tx_can_flags = 0;
-
-	if (cf->can_id & CAN_EFF_FLAG) {
-		cmd->id = CMD_TX_EXT_MESSAGE;
-		cmd->u.tx_can.data[0] = (cf->can_id >> 24) & 0x1f;
-		cmd->u.tx_can.data[1] = (cf->can_id >> 18) & 0x3f;
-		cmd->u.tx_can.data[2] = (cf->can_id >> 14) & 0x0f;
-		cmd->u.tx_can.data[3] = (cf->can_id >> 6) & 0xff;
-		cmd->u.tx_can.data[4] = cf->can_id & 0x3f;
-	} else {
-		cmd->id = CMD_TX_STD_MESSAGE;
-		cmd->u.tx_can.data[0] = (cf->can_id >> 6) & 0x1f;
-		cmd->u.tx_can.data[1] = cf->can_id & 0x3f;
-	}
-
-	cmd->u.tx_can.data[5] = cf->can_dlc;
-	memcpy(&cmd->u.tx_can.data[6], cf->data, cf->can_dlc);
-
-	if (cf->can_id & CAN_RTR_FLAG)
-		*cmd_tx_can_flags |= MSG_FLAG_REMOTE_FRAME;
-
-	spin_lock_irqsave(&priv->tx_contexts_lock, flags);
-	for (i = 0; i < dev->max_tx_urbs; i++) {
-		if (priv->tx_contexts[i].echo_index == dev->max_tx_urbs) {
-			context = &priv->tx_contexts[i];
-
-			context->echo_index = i;
-			can_put_echo_skb(skb, netdev, context->echo_index);
-			++priv->active_tx_contexts;
-			if (priv->active_tx_contexts >= dev->max_tx_urbs)
-				netif_stop_queue(netdev);
-
-			break;
-		}
-	}
-	spin_unlock_irqrestore(&priv->tx_contexts_lock, flags);
-
-	/* This should never happen; it implies a flow control bug */
-	if (!context) {
-		netdev_warn(netdev, "cannot find free context\n");
-
-		kfree(buf);
-		ret =  NETDEV_TX_BUSY;
-		goto freeurb;
-	}
-
-	context->priv = priv;
-	context->dlc = cf->can_dlc;
-
-	cmd->u.tx_can.tid = context->echo_index;
-
-	usb_fill_bulk_urb(urb, dev->udev,
-			  usb_sndbulkpipe(dev->udev,
-					  dev->bulk_out->bEndpointAddress),
-			  buf, cmd->len,
-			  kvaser_usb_write_bulk_callback, context);
-	usb_anchor_urb(urb, &priv->tx_submitted);
-
-	err = usb_submit_urb(urb, GFP_ATOMIC);
-	if (unlikely(err)) {
-		spin_lock_irqsave(&priv->tx_contexts_lock, flags);
-
-		can_free_echo_skb(netdev, context->echo_index);
-		context->echo_index = dev->max_tx_urbs;
-		--priv->active_tx_contexts;
-		netif_wake_queue(netdev);
-
-		spin_unlock_irqrestore(&priv->tx_contexts_lock, flags);
-
-		usb_unanchor_urb(urb);
-		kfree(buf);
-
-		stats->tx_dropped++;
-
-		if (err == -ENODEV)
-			netif_device_detach(netdev);
-		else
-			netdev_warn(netdev, "Failed tx_urb %d\n", err);
-
-		goto freeurb;
-	}
-
-	ret = NETDEV_TX_OK;
-
-freeurb:
-	usb_free_urb(urb);
-	return ret;
-}
-
-static const struct net_device_ops kvaser_usb_netdev_ops = {
-	.ndo_open = kvaser_usb_open,
-	.ndo_stop = kvaser_usb_close,
-	.ndo_start_xmit = kvaser_usb_start_xmit,
-	.ndo_change_mtu = can_change_mtu,
-};
-
-static const struct can_bittiming_const kvaser_usb_bittiming_const = {
-	.name = "kvaser_usb",
-	.tseg1_min = KVASER_USB_TSEG1_MIN,
-	.tseg1_max = KVASER_USB_TSEG1_MAX,
-	.tseg2_min = KVASER_USB_TSEG2_MIN,
-	.tseg2_max = KVASER_USB_TSEG2_MAX,
-	.sjw_max = KVASER_USB_SJW_MAX,
-	.brp_min = KVASER_USB_BRP_MIN,
-	.brp_max = KVASER_USB_BRP_MAX,
-	.brp_inc = KVASER_USB_BRP_INC,
-};
-
-static int kvaser_usb_set_bittiming(struct net_device *netdev)
-{
-	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
-	struct can_bittiming *bt = &priv->can.bittiming;
-	struct kvaser_usb *dev = priv->dev;
-	struct kvaser_cmd *cmd;
-	int rc;
-
-	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
-	if (!cmd)
-		return -ENOMEM;
-
-	cmd->id = CMD_SET_BUS_PARAMS;
-	cmd->len = CMD_HEADER_LEN + sizeof(struct kvaser_cmd_busparams);
-	cmd->u.busparams.channel = priv->channel;
-	cmd->u.busparams.tid = 0xff;
-	cmd->u.busparams.bitrate = cpu_to_le32(bt->bitrate);
-	cmd->u.busparams.sjw = bt->sjw;
-	cmd->u.busparams.tseg1 = bt->prop_seg + bt->phase_seg1;
-	cmd->u.busparams.tseg2 = bt->phase_seg2;
-
-	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
-		cmd->u.busparams.no_samp = 3;
-	else
-		cmd->u.busparams.no_samp = 1;
-
-	rc = kvaser_usb_send_cmd(dev, cmd);
-
-	kfree(cmd);
-	return rc;
-}
-
-static int kvaser_usb_set_mode(struct net_device *netdev,
-			       enum can_mode mode)
-{
-	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
-	int err;
-
-	switch (mode) {
-	case CAN_MODE_START:
-		err = kvaser_usb_simple_cmd_async(priv, CMD_START_CHIP);
-		if (err)
-			return err;
-		break;
-	default:
-		return -EOPNOTSUPP;
-	}
-
-	return 0;
-}
-
-static int kvaser_usb_get_berr_counter(const struct net_device *netdev,
-				       struct can_berr_counter *bec)
-{
-	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
-
-	*bec = priv->bec;
-
-	return 0;
-}
-
-static void kvaser_usb_remove_interfaces(struct kvaser_usb *dev)
-{
-	int i;
-
-	for (i = 0; i < dev->nchannels; i++) {
-		if (!dev->nets[i])
-			continue;
-
-		unregister_candev(dev->nets[i]->netdev);
-	}
-
-	kvaser_usb_unlink_all_urbs(dev);
-
-	for (i = 0; i < dev->nchannels; i++) {
-		if (!dev->nets[i])
-			continue;
-
-		free_candev(dev->nets[i]->netdev);
-	}
-}
-
-static int kvaser_usb_init_one(struct kvaser_usb *dev,
-			       const struct usb_device_id *id, int channel)
-{
-	struct net_device *netdev;
-	struct kvaser_usb_net_priv *priv;
-	int err;
-
-	err = kvaser_usb_send_simple_cmd(dev, CMD_RESET_CHIP, channel);
-	if (err)
-		return err;
-
-	netdev = alloc_candev(sizeof(*priv) +
-			      dev->max_tx_urbs * sizeof(*priv->tx_contexts),
-			      dev->max_tx_urbs);
-	if (!netdev) {
-		dev_err(&dev->intf->dev, "Cannot alloc candev\n");
-		return -ENOMEM;
-	}
-
-	priv = netdev_priv(netdev);
-
-	init_usb_anchor(&priv->tx_submitted);
-	init_completion(&priv->start_comp);
-	init_completion(&priv->stop_comp);
-
-	priv->dev = dev;
-	priv->netdev = netdev;
-	priv->channel = channel;
-
-	spin_lock_init(&priv->tx_contexts_lock);
-	kvaser_usb_reset_tx_urb_contexts(priv);
-
-	priv->can.state = CAN_STATE_STOPPED;
-	priv->can.clock.freq = CAN_USB_CLOCK;
-	priv->can.bittiming_const = &kvaser_usb_bittiming_const;
-	priv->can.do_set_bittiming = kvaser_usb_set_bittiming;
-	priv->can.do_set_mode = kvaser_usb_set_mode;
-	if (id->driver_info & KVASER_HAS_TXRX_ERRORS)
-		priv->can.do_get_berr_counter = kvaser_usb_get_berr_counter;
-	priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
-	if (id->driver_info & KVASER_HAS_SILENT_MODE)
-		priv->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY;
-
-	netdev->flags |= IFF_ECHO;
-
-	netdev->netdev_ops = &kvaser_usb_netdev_ops;
-
-	SET_NETDEV_DEV(netdev, &dev->intf->dev);
-	netdev->dev_id = channel;
-
-	dev->nets[channel] = priv;
-
-	err = register_candev(netdev);
-	if (err) {
-		dev_err(&dev->intf->dev, "Failed to register CAN device\n");
-		free_candev(netdev);
-		dev->nets[channel] = NULL;
-		return err;
-	}
-
-	netdev_dbg(netdev, "device registered\n");
-
-	return 0;
-}
-
-static int kvaser_usb_setup_endpoints(struct kvaser_usb *dev)
-{
-	const struct usb_host_interface *iface_desc;
-	struct usb_endpoint_descriptor *endpoint;
-	int i;
-
-	iface_desc = &dev->intf->altsetting[0];
-
-	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
-		endpoint = &iface_desc->endpoint[i].desc;
-
-		if (!dev->bulk_in && usb_endpoint_is_bulk_in(endpoint))
-			dev->bulk_in = endpoint;
-
-		if (!dev->bulk_out && usb_endpoint_is_bulk_out(endpoint))
-			dev->bulk_out = endpoint;
-
-		/* use first bulk endpoint for in and out */
-		if (dev->bulk_in && dev->bulk_out)
-			return 0;
-	}
-
-	return -ENODEV;
-}
-
-static int kvaser_usb_probe(struct usb_interface *intf,
-			    const struct usb_device_id *id)
-{
-	struct kvaser_usb *dev;
-	int err = -ENOMEM;
-	int i, retry = 3;
-
-	dev = devm_kzalloc(&intf->dev, sizeof(*dev), GFP_KERNEL);
-	if (!dev)
-		return -ENOMEM;
-
-	if (kvaser_is_leaf(id)) {
-		dev->family = KVASER_LEAF;
-	} else if (kvaser_is_usbcan(id)) {
-		dev->family = KVASER_USBCAN;
-	} else {
-		dev_err(&intf->dev,
-			"Product ID (%d) does not belong to any known Kvaser USB family",
-			id->idProduct);
-		return -ENODEV;
-	}
-
-	dev->intf = intf;
-
-	err = kvaser_usb_setup_endpoints(dev);
-	if (err) {
-		dev_err(&intf->dev, "Cannot get usb endpoint(s)");
-		return err;
-	}
-
-	dev->udev = interface_to_usbdev(intf);
-
-	init_usb_anchor(&dev->rx_submitted);
-
-	usb_set_intfdata(intf, dev);
-
-	/* On some x86 laptops, plugging a Kvaser device again after
-	 * an unplug makes the firmware always ignore the very first
-	 * command. For such a case, provide some room for retries
-	 * instead of completely exiting the driver.
-	 */
-	do {
-		err = kvaser_usb_get_software_info(dev);
-	} while (--retry && err == -ETIMEDOUT);
-
-	if (err) {
-		dev_err(&intf->dev,
-			"Cannot get software infos, error %d\n", err);
-		return err;
-	}
-
-	dev_dbg(&intf->dev, "Firmware version: %d.%d.%d\n",
-		((dev->fw_version >> 24) & 0xff),
-		((dev->fw_version >> 16) & 0xff),
-		(dev->fw_version & 0xffff));
-
-	dev_dbg(&intf->dev, "Max outstanding tx = %d URBs\n", dev->max_tx_urbs);
-
-	err = kvaser_usb_get_card_info(dev);
-	if (err) {
-		dev_err(&intf->dev,
-			"Cannot get card infos, error %d\n", err);
-		return err;
-	}
-
-	for (i = 0; i < dev->nchannels; i++) {
-		err = kvaser_usb_init_one(dev, id, i);
-		if (err) {
-			kvaser_usb_remove_interfaces(dev);
-			return err;
-		}
-	}
-
-	return 0;
-}
-
-static void kvaser_usb_disconnect(struct usb_interface *intf)
-{
-	struct kvaser_usb *dev = usb_get_intfdata(intf);
-
-	usb_set_intfdata(intf, NULL);
-
-	if (!dev)
-		return;
-
-	kvaser_usb_remove_interfaces(dev);
-}
-
-static struct usb_driver kvaser_usb_driver = {
-	.name = "kvaser_usb",
-	.probe = kvaser_usb_probe,
-	.disconnect = kvaser_usb_disconnect,
-	.id_table = kvaser_usb_table,
-};
-
-module_usb_driver(kvaser_usb_driver);
-
-MODULE_AUTHOR("Olivier Sobrie <[e-mail]>");
-MODULE_DESCRIPTION("CAN driver for Kvaser CAN/USB devices");
-MODULE_LICENSE("GPL v2");

drivers/net/can/usb/kvaser_usb/Makefile

···
+obj-$(CONFIG_CAN_KVASER_USB) += kvaser_usb.o
+kvaser_usb-y = kvaser_usb_core.o kvaser_usb_leaf.o

drivers/net/can/usb/kvaser_usb/kvaser_usb.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Parts of this driver are based on the following:
+ *  - Kvaser linux leaf driver (version 4.78)
+ *  - CAN driver for esd CAN-USB/2
+ *  - Kvaser linux usbcanII driver (version 5.3)
+ *
+ * Copyright (C) 2002-2018 KVASER AB, Sweden. All rights reserved.
+ * Copyright (C) 2010 Matthias Fuchs <[e-mail]>, esd gmbh
+ * Copyright (C) 2012 Olivier Sobrie <[e-mail]>
+ * Copyright (C) 2015 Valeo S.A.
+ */
+
+#ifndef KVASER_USB_H
+#define KVASER_USB_H
+
+/* Kvaser USB CAN dongles are divided into two major families:
+ * - Leaf: Based on Renesas M32C, running firmware labeled as 'filo'
+ * - UsbcanII: Based on Renesas M16C, running firmware labeled as 'helios'
+ */
+
+#include <linux/completion.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/usb.h>
+
+#include <linux/can.h>
+#include <linux/can/dev.h>
+
+#define KVASER_USB_MAX_RX_URBS			4
+#define KVASER_USB_MAX_TX_URBS			128
+#define KVASER_USB_TIMEOUT			1000 /* msecs */
+#define KVASER_USB_RX_BUFFER_SIZE		3072
+#define KVASER_USB_MAX_NET_DEVICES		3
+
+/* USB devices features */
+#define KVASER_USB_HAS_SILENT_MODE		BIT(0)
+#define KVASER_USB_HAS_TXRX_ERRORS		BIT(1)
+
+struct kvaser_usb_dev_cfg;
+
+enum kvaser_usb_leaf_family {
+	KVASER_LEAF,
+	KVASER_USBCAN,
+};
+
+struct kvaser_usb_dev_card_data {
+	u32 ctrlmode_supported;
+	struct {
+		enum kvaser_usb_leaf_family family;
+	} leaf;
+};
+
+/* Context for an outstanding, not yet ACKed, transmission */
+struct kvaser_usb_tx_urb_context {
+	struct kvaser_usb_net_priv *priv;
+	u32 echo_index;
+	int dlc;
+};
+
+struct kvaser_usb {
+	struct usb_device *udev;
+	struct usb_interface *intf;
+	struct kvaser_usb_net_priv *nets[KVASER_USB_MAX_NET_DEVICES];
+	const struct kvaser_usb_dev_ops *ops;
+	const struct kvaser_usb_dev_cfg *cfg;
+
+	struct usb_endpoint_descriptor *bulk_in, *bulk_out;
+	struct usb_anchor rx_submitted;
+
+	/* @max_tx_urbs: Firmware-reported maximum number of outstanding,
+	 * not yet ACKed, transmissions on this device. This value is
+	 * also used as a sentinel for marking free tx contexts.
+	 */
+	u32 fw_version;
+	unsigned int nchannels;
+	unsigned int max_tx_urbs;
+	struct kvaser_usb_dev_card_data card_data;
+
+	bool rxinitdone;
+	void *rxbuf[KVASER_USB_MAX_RX_URBS];
+	dma_addr_t rxbuf_dma[KVASER_USB_MAX_RX_URBS];
+};
+
+struct kvaser_usb_net_priv {
+	struct can_priv can;
+	struct can_berr_counter bec;
+
+	struct kvaser_usb *dev;
+	struct net_device *netdev;
+	int channel;
+
+	struct completion start_comp, stop_comp;
+	struct usb_anchor tx_submitted;
+
+	spinlock_t tx_contexts_lock; /* lock for active_tx_contexts */
+	int active_tx_contexts;
+	struct kvaser_usb_tx_urb_context tx_contexts[];
+};
+
+/**
+ * struct kvaser_usb_dev_ops - Device specific functions
+ * @dev_set_mode:		used for can.do_set_mode
+ * @dev_set_bittiming:		used for can.do_set_bittiming
+ * @dev_get_berr_counter:	used for can.do_get_berr_counter
+ *
+ * @dev_setup_endpoints:	setup USB in and out endpoints
+ * @dev_init_card:		initialize card
+ * @dev_get_software_info:	get software info
+ * @dev_get_card_info:		get card info
+ *
+ * @dev_set_opt_mode:		set ctrlmod
+ * @dev_start_chip:		start the CAN controller
+ * @dev_stop_chip:		stop the CAN controller
+ * @dev_reset_chip:		reset the CAN controller
+ * @dev_flush_queue:		flush outstanding CAN messages
+ * @dev_read_bulk_callback:	handle incoming commands
+ * @dev_frame_to_cmd:		translate struct can_frame into device command
+ */
+struct kvaser_usb_dev_ops {
+	int (*dev_set_mode)(struct net_device *netdev, enum can_mode mode);
+	int (*dev_set_bittiming)(struct net_device *netdev);
+	int (*dev_get_berr_counter)(const struct net_device *netdev,
+				    struct can_berr_counter *bec);
+	int (*dev_setup_endpoints)(struct kvaser_usb *dev);
+	int (*dev_init_card)(struct kvaser_usb *dev);
+	int (*dev_get_software_info)(struct kvaser_usb *dev);
+	int (*dev_get_card_info)(struct kvaser_usb *dev);
+	int (*dev_set_opt_mode)(const struct kvaser_usb_net_priv *priv);
+	int (*dev_start_chip)(struct kvaser_usb_net_priv *priv);
+	int (*dev_stop_chip)(struct kvaser_usb_net_priv *priv);
+	int (*dev_reset_chip)(struct kvaser_usb *dev, int channel);
+	int (*dev_flush_queue)(struct kvaser_usb_net_priv *priv);
+	void (*dev_read_bulk_callback)(struct kvaser_usb *dev, void *buf,
+				       int len);
+	void *(*dev_frame_to_cmd)(const struct kvaser_usb_net_priv *priv,
+				  const struct sk_buff *skb, int *frame_len,
+				  int *cmd_len, u16 transid);
+};
+
+struct kvaser_usb_dev_cfg {
+	const struct can_clock clock;
+	const unsigned int timestamp_freq;
+	const struct can_bittiming_const * const bittiming_const;
+	const struct can_bittiming_const * const data_bittiming_const;
+};
+
+extern const struct kvaser_usb_dev_ops kvaser_usb_leaf_dev_ops;
+
+int kvaser_usb_recv_cmd(const struct kvaser_usb *dev, void *cmd, int len,
+			int *actual_len);
+
+int kvaser_usb_send_cmd(const struct kvaser_usb *dev, void *cmd, int len);
+
+int kvaser_usb_send_cmd_async(struct kvaser_usb_net_priv *priv, void *cmd,
+			      int len);
+
+int kvaser_usb_can_rx_over_error(struct net_device *netdev);
+#endif /* KVASER_USB_H */

drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c

···
+// SPDX-License-Identifier: GPL-2.0
+/* Parts of this driver are based on the following:
+ *  - Kvaser linux leaf driver (version 4.78)
+ *  - CAN driver for esd CAN-USB/2
+ *  - Kvaser linux usbcanII driver (version 5.3)
+ *
+ * Copyright (C) 2002-2018 KVASER AB, Sweden. All rights reserved.
+ * Copyright (C) 2010 Matthias Fuchs <[e-mail]>, esd gmbh
+ * Copyright (C) 2012 Olivier Sobrie <[e-mail]>
+ * Copyright (C) 2015 Valeo S.A.
+ */
+
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/gfp.h>
+#include <linux/if.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/usb.h>
+
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+#include <linux/can/netlink.h>
+
+#include "kvaser_usb.h"
+
+/* Kvaser USB vendor id. */
+#define KVASER_VENDOR_ID			0x0bfd
+
+/* Kvaser Leaf USB devices product ids */
+#define USB_LEAF_DEVEL_PRODUCT_ID		10
+#define USB_LEAF_LITE_PRODUCT_ID		11
+#define USB_LEAF_PRO_PRODUCT_ID			12
+#define USB_LEAF_SPRO_PRODUCT_ID		14
+#define USB_LEAF_PRO_LS_PRODUCT_ID		15
+#define USB_LEAF_PRO_SWC_PRODUCT_ID		16
+#define USB_LEAF_PRO_LIN_PRODUCT_ID		17
+#define USB_LEAF_SPRO_LS_PRODUCT_ID		18
+#define USB_LEAF_SPRO_SWC_PRODUCT_ID		19
+#define USB_MEMO2_DEVEL_PRODUCT_ID		22
+#define USB_MEMO2_HSHS_PRODUCT_ID		23
+#define USB_UPRO_HSHS_PRODUCT_ID		24
+#define USB_LEAF_LITE_GI_PRODUCT_ID		25
+#define USB_LEAF_PRO_OBDII_PRODUCT_ID		26
+#define USB_MEMO2_HSLS_PRODUCT_ID		27
+#define USB_LEAF_LITE_CH_PRODUCT_ID		28
+#define USB_BLACKBIRD_SPRO_PRODUCT_ID		29
+#define USB_OEM_MERCURY_PRODUCT_ID		34
+#define USB_OEM_LEAF_PRODUCT_ID			35
+#define USB_CAN_R_PRODUCT_ID			39
+#define USB_LEAF_LITE_V2_PRODUCT_ID		288
+#define USB_MINI_PCIE_HS_PRODUCT_ID		289
+#define USB_LEAF_LIGHT_HS_V2_OEM_PRODUCT_ID	290
+#define USB_USBCAN_LIGHT_2HS_PRODUCT_ID		291
+#define USB_MINI_PCIE_2HS_PRODUCT_ID		292
+
+/* Kvaser USBCan-II devices product ids */
+#define USB_USBCAN_REVB_PRODUCT_ID		2
+#define USB_VCI2_PRODUCT_ID			3
+#define USB_USBCAN2_PRODUCT_ID			4
+#define USB_MEMORATOR_PRODUCT_ID		5
+
+static inline bool kvaser_is_leaf(const struct usb_device_id *id)
+{
+	return id->idProduct >= USB_LEAF_DEVEL_PRODUCT_ID &&
+	       id->idProduct <= USB_MINI_PCIE_2HS_PRODUCT_ID;
+}
+
+static inline bool kvaser_is_usbcan(const struct usb_device_id *id)
+{
+	return id->idProduct >= USB_USBCAN_REVB_PRODUCT_ID &&
+	       id->idProduct <= USB_MEMORATOR_PRODUCT_ID;
+}
+
+static const struct usb_device_id kvaser_usb_table[] = {
+	/* Leaf USB product IDs */
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_DEVEL_PRODUCT_ID) },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_PRODUCT_ID) },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS |
+			       KVASER_USB_HAS_SILENT_MODE },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_SPRO_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS |
+			       KVASER_USB_HAS_SILENT_MODE },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_LS_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS |
+			       KVASER_USB_HAS_SILENT_MODE },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_SWC_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS |
+			       KVASER_USB_HAS_SILENT_MODE },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_LIN_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS |
+			       KVASER_USB_HAS_SILENT_MODE },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_SPRO_LS_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS |
+			       KVASER_USB_HAS_SILENT_MODE },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_SPRO_SWC_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS |
+			       KVASER_USB_HAS_SILENT_MODE },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MEMO2_DEVEL_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS |
+			       KVASER_USB_HAS_SILENT_MODE },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MEMO2_HSHS_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS |
+			       KVASER_USB_HAS_SILENT_MODE },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_UPRO_HSHS_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_GI_PRODUCT_ID) },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_OBDII_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS |
+			       KVASER_USB_HAS_SILENT_MODE },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MEMO2_HSLS_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_CH_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_BLACKBIRD_SPRO_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_OEM_MERCURY_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_OEM_LEAF_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_CAN_R_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_V2_PRODUCT_ID) },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MINI_PCIE_HS_PRODUCT_ID) },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LIGHT_HS_V2_OEM_PRODUCT_ID) },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_USBCAN_LIGHT_2HS_PRODUCT_ID) },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MINI_PCIE_2HS_PRODUCT_ID) },
+
+	/* USBCANII USB product IDs */
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_USBCAN2_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_USBCAN_REVB_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MEMORATOR_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_VCI2_PRODUCT_ID),
+		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+	{ }
+};
+MODULE_DEVICE_TABLE(usb, kvaser_usb_table);
+
+int kvaser_usb_send_cmd(const struct kvaser_usb *dev, void *cmd, int len)
+{
+	int actual_len; /* Not used */
+
+	return usb_bulk_msg(dev->udev,
+			    usb_sndbulkpipe(dev->udev,
+					    dev->bulk_out->bEndpointAddress),
+			    cmd, len, &actual_len, KVASER_USB_TIMEOUT);
+}
+
+int kvaser_usb_recv_cmd(const struct kvaser_usb *dev, void *cmd, int len,
+			int *actual_len)
+{
+	return usb_bulk_msg(dev->udev,
+			    usb_rcvbulkpipe(dev->udev,
+					    dev->bulk_in->bEndpointAddress),
+			    cmd, len, actual_len, KVASER_USB_TIMEOUT);
+}
+
+static void kvaser_usb_send_cmd_callback(struct urb *urb)
+{
+	struct net_device *netdev = urb->context;
+
+	kfree(urb->transfer_buffer);
+
+	if (urb->status)
+		netdev_warn(netdev, "urb status received: %d\n", urb->status);
+}
+
+int kvaser_usb_send_cmd_async(struct kvaser_usb_net_priv *priv, void *cmd,
+			      int len)
+{
+	struct kvaser_usb *dev = priv->dev;
+	struct net_device *netdev = priv->netdev;
+	struct urb *urb;
+	int err;
+
+	urb = usb_alloc_urb(0, GFP_ATOMIC);
+	if (!urb)
+		return -ENOMEM;
+
+	usb_fill_bulk_urb(urb, dev->udev,
+			  usb_sndbulkpipe(dev->udev,
+					  dev->bulk_out->bEndpointAddress),
+			  cmd, len, kvaser_usb_send_cmd_callback, netdev);
+	usb_anchor_urb(urb, &priv->tx_submitted);
+
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+	if (err) {
+		netdev_err(netdev, "Error transmitting URB\n");
+		usb_unanchor_urb(urb);
+	}
+	usb_free_urb(urb);
+
+	return 0;
+}
+
+int kvaser_usb_can_rx_over_error(struct net_device *netdev)
+{
+	struct net_device_stats *stats = &netdev->stats;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+
+	stats->rx_over_errors++;
+	stats->rx_errors++;
+
+	skb = alloc_can_err_skb(netdev, &cf);
+	if (!skb) {
+		stats->rx_dropped++;
+		netdev_warn(netdev, "No memory left for err_skb\n");
+		return -ENOMEM;
+	}
+
+	cf->can_id |= CAN_ERR_CRTL;
+	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+
+	stats->rx_packets++;
+	stats->rx_bytes += cf->can_dlc;
+	netif_rx(skb);
+
+	return 0;
+}
+
+static void kvaser_usb_read_bulk_callback(struct urb *urb)
+{
+	struct kvaser_usb *dev = urb->context;
+	int err;
+	unsigned int i;
+
+	switch (urb->status) {
+	case 0:
+		break;
+	case -ENOENT:
+	case -EPIPE:
+	case -EPROTO:
+	case -ESHUTDOWN:
+		return;
+	default:
+		dev_info(&dev->intf->dev, "Rx URB aborted (%d)\n", urb->status);
+		goto resubmit_urb;
+	}
+
+	dev->ops->dev_read_bulk_callback(dev, urb->transfer_buffer,
+					 urb->actual_length);
+
+resubmit_urb:
+	usb_fill_bulk_urb(urb, dev->udev,
+			  usb_rcvbulkpipe(dev->udev,
+					  dev->bulk_in->bEndpointAddress),
+			  urb->transfer_buffer, KVASER_USB_RX_BUFFER_SIZE,
+			  kvaser_usb_read_bulk_callback, dev);
+
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+	if (err == -ENODEV) {
+		for (i = 0; i < dev->nchannels; i++) {
+			if (!dev->nets[i])
+				continue;
+
+			netif_device_detach(dev->nets[i]->netdev);
+		}
+	} else if (err) {
+		dev_err(&dev->intf->dev,
+			"Failed resubmitting read bulk urb: %d\n", err);
+	}
+}
+
+static int kvaser_usb_setup_rx_urbs(struct kvaser_usb *dev)
+{
+	int i, err = 0;
+
+	if (dev->rxinitdone)
+		return 0;
+
+	for (i = 0; i < KVASER_USB_MAX_RX_URBS; i++) {
+		struct urb *urb = NULL;
+		u8 *buf = NULL;
+		dma_addr_t buf_dma;
+
+		urb = usb_alloc_urb(0, GFP_KERNEL);
+		if (!urb) {
+			err = -ENOMEM;
+			break;
+		}
+
+		buf = usb_alloc_coherent(dev->udev, KVASER_USB_RX_BUFFER_SIZE,
+					 GFP_KERNEL, &buf_dma);
+		if (!buf) {
+			dev_warn(&dev->intf->dev,
+				 "No memory left for USB buffer\n");
+			usb_free_urb(urb);
+			err = -ENOMEM;
+			break;
+		}
+
+		usb_fill_bulk_urb(urb, dev->udev,
+				  usb_rcvbulkpipe
+					(dev->udev,
+					 dev->bulk_in->bEndpointAddress),
+				  buf, KVASER_USB_RX_BUFFER_SIZE,
+				  kvaser_usb_read_bulk_callback, dev);
+		urb->transfer_dma = buf_dma;
+		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+		usb_anchor_urb(urb, &dev->rx_submitted);
+
+		err = usb_submit_urb(urb, GFP_KERNEL);
+		if (err) {
+			usb_unanchor_urb(urb);
+			usb_free_coherent(dev->udev,
+					  KVASER_USB_RX_BUFFER_SIZE, buf,
+					  buf_dma);
+			usb_free_urb(urb);
+			break;
+		}
+
+		dev->rxbuf[i] = buf;
+		dev->rxbuf_dma[i] = buf_dma;
+
+		usb_free_urb(urb);
+	}
+
+	if (i == 0) {
+		dev_warn(&dev->intf->dev, "Cannot setup read URBs, error %d\n",
+			 err);
+		return err;
+	} else if (i < KVASER_USB_MAX_RX_URBS) {
+		dev_warn(&dev->intf->dev, "RX performances may be slow\n");
+	}
+
+	dev->rxinitdone = true;
+
+	return 0;
+}
+
+static int kvaser_usb_open(struct net_device *netdev)
+{
+	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
+	struct kvaser_usb *dev = priv->dev;
+	int err;
+
+	err = open_candev(netdev);
+	if (err)
+		return err;
+
+	err = kvaser_usb_setup_rx_urbs(dev);
+	if (err)
+		goto error;
+
+	err = dev->ops->dev_set_opt_mode(priv);
+	if (err)
+		goto error;
+
+	err = dev->ops->dev_start_chip(priv);
+	if (err) {
+		netdev_warn(netdev, "Cannot start device, error %d\n", err);
+		goto error;
+	}
+
+	priv->can.state = CAN_STATE_ERROR_ACTIVE;
+
+	return 0;
+
+error:
+	close_candev(netdev);
+	return err;
+}
+
+static void kvaser_usb_reset_tx_urb_contexts(struct kvaser_usb_net_priv *priv)
+{
+	int i, max_tx_urbs;
+
+	max_tx_urbs = priv->dev->max_tx_urbs;
+
+	priv->active_tx_contexts = 0;
+	for (i = 0; i < max_tx_urbs; i++)
+		priv->tx_contexts[i].echo_index = max_tx_urbs;
+}
+
+/* This method might sleep. Do not call it in the atomic context
+ * of URB completions.
+ */
+static void kvaser_usb_unlink_tx_urbs(struct kvaser_usb_net_priv *priv)
+{
+	usb_kill_anchored_urbs(&priv->tx_submitted);
+	kvaser_usb_reset_tx_urb_contexts(priv);
+}
+
+static void kvaser_usb_unlink_all_urbs(struct kvaser_usb *dev)
+{
+	int i;
+
+	usb_kill_anchored_urbs(&dev->rx_submitted);
+
+	for (i = 0; i < KVASER_USB_MAX_RX_URBS; i++)
+		usb_free_coherent(dev->udev, KVASER_USB_RX_BUFFER_SIZE,
+				  dev->rxbuf[i], dev->rxbuf_dma[i]);
+
+	for (i = 0; i < dev->nchannels; i++) {
+		struct kvaser_usb_net_priv *priv = dev->nets[i];
+
+		if (priv)
+			kvaser_usb_unlink_tx_urbs(priv);
+	}
+}
+
+static int kvaser_usb_close(struct net_device *netdev)
+{
+	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
+	struct kvaser_usb *dev = priv->dev;
+	int err;
+
+	netif_stop_queue(netdev);
+
+	err = dev->ops->dev_flush_queue(priv);
+	if (err)
+		netdev_warn(netdev, "Cannot flush queue, error %d\n", err);
+
+	if (dev->ops->dev_reset_chip) {
+		err = dev->ops->dev_reset_chip(dev, priv->channel);
+		if (err)
+			netdev_warn(netdev, "Cannot reset card, error %d\n",
+				    err);
+	}
+
+	err = dev->ops->dev_stop_chip(priv);
+	if (err)
+		netdev_warn(netdev, "Cannot stop device, error %d\n", err);
+
+	/* reset tx contexts */
+	kvaser_usb_unlink_tx_urbs(priv);
+
+	priv->can.state = CAN_STATE_STOPPED;
+	close_candev(priv->netdev);
+
+	return 0;
+}
+
+static void kvaser_usb_write_bulk_callback(struct urb *urb)
+{
+	struct kvaser_usb_tx_urb_context *context = urb->context;
+	struct kvaser_usb_net_priv *priv;
+	struct net_device *netdev;
+
+	if (WARN_ON(!context))
+		return;
+
+	priv = context->priv;
+	netdev = priv->netdev;
+
+	kfree(urb->transfer_buffer);
+
+	if (!netif_device_present(netdev))
+		return;
+
+	if (urb->status)
+		netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
+}
+
+static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb,
+					 struct net_device *netdev)
+{
+	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
+	struct kvaser_usb *dev = priv->dev;
+	struct net_device_stats *stats = &netdev->stats;
+	struct kvaser_usb_tx_urb_context *context = NULL;
+	struct urb *urb;
+	void *buf;
+	int cmd_len = 0;
+	int err, ret = NETDEV_TX_OK;
+	unsigned int i;
+	unsigned long flags;
+
+	if (can_dropped_invalid_skb(netdev, skb))
+		return NETDEV_TX_OK;
+
+	urb = usb_alloc_urb(0, GFP_ATOMIC);
+	if (!urb) {
+		stats->tx_dropped++;
+		dev_kfree_skb(skb);
+		return NETDEV_TX_OK;
+	}
+
+	spin_lock_irqsave(&priv->tx_contexts_lock, flags);
+	for (i = 0; i < dev->max_tx_urbs; i++) {
+		if (priv->tx_contexts[i].echo_index == dev->max_tx_urbs) {
+			context = &priv->tx_contexts[i];
+
+			context->echo_index = i;
+			can_put_echo_skb(skb, netdev, context->echo_index);
+			++priv->active_tx_contexts;
+			if (priv->active_tx_contexts >= (int)dev->max_tx_urbs)
+				netif_stop_queue(netdev);
+
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&priv->tx_contexts_lock, flags);
+
+	/* This should never happen; it implies a flow control bug */
+	if (!context) {
+		netdev_warn(netdev, "cannot find free context\n");
+
+		ret = NETDEV_TX_BUSY;
+		goto freeurb;
+	}
+
+	buf = dev->ops->dev_frame_to_cmd(priv, skb, &context->dlc, &cmd_len,
+					 context->echo_index);
+	if (!buf) {
+		stats->tx_dropped++;
+		dev_kfree_skb(skb);
+		spin_lock_irqsave(&priv->tx_contexts_lock, flags);
+
+		can_free_echo_skb(netdev, context->echo_index);
+		context->echo_index = dev->max_tx_urbs;
+		--priv->active_tx_contexts;
+		netif_wake_queue(netdev);
+
+		spin_unlock_irqrestore(&priv->tx_contexts_lock, flags);
+		goto freeurb;
+	}
+
+	context->priv = priv;
+
+	usb_fill_bulk_urb(urb, dev->udev,
+			  usb_sndbulkpipe(dev->udev,
+					  dev->bulk_out->bEndpointAddress),
+			  buf, cmd_len, kvaser_usb_write_bulk_callback,
+			  context);
+	usb_anchor_urb(urb, &priv->tx_submitted);
+
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+	if (unlikely(err)) {
+		spin_lock_irqsave(&priv->tx_contexts_lock, flags);
+
+		can_free_echo_skb(netdev, context->echo_index);
+		context->echo_index = dev->max_tx_urbs;
+		--priv->active_tx_contexts;
+		netif_wake_queue(netdev);
+
+		spin_unlock_irqrestore(&priv->tx_contexts_lock, flags);
+
+		usb_unanchor_urb(urb);
+		kfree(buf);
+
+		stats->tx_dropped++;
+
+		if (err == -ENODEV)
+			netif_device_detach(netdev);
+		else
+			netdev_warn(netdev, "Failed tx_urb %d\n", err);
+
+		goto freeurb;
+	}
+
+	ret = NETDEV_TX_OK;
+
+freeurb:
+	usb_free_urb(urb);
+	return ret;
+}
+
+static const struct net_device_ops kvaser_usb_netdev_ops = {
+	.ndo_open = kvaser_usb_open,
+	.ndo_stop = kvaser_usb_close,
+	.ndo_start_xmit = kvaser_usb_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
+};
+
+static void kvaser_usb_remove_interfaces(struct kvaser_usb *dev)
+{
+	int i;
+
+	for (i = 0; i < dev->nchannels; i++) {
+		if (!dev->nets[i])
+			continue;
+
+		unregister_candev(dev->nets[i]->netdev);
+	}
+
+	kvaser_usb_unlink_all_urbs(dev);
+
+	for (i = 0; i < dev->nchannels; i++) {
+		if (!dev->nets[i])
+			continue;
+
+		free_candev(dev->nets[i]->netdev);
+	}
+}
+
+static int kvaser_usb_init_one(struct kvaser_usb *dev,
+			       const struct usb_device_id *id, int channel)
+{
+	struct net_device *netdev;
+	struct kvaser_usb_net_priv *priv;
+	int err;
+
+	if (dev->ops->dev_reset_chip) {
+		err = dev->ops->dev_reset_chip(dev, channel);
+		if (err)
+			return err;
+	}
+
+	netdev = alloc_candev(sizeof(*priv) +
+			      dev->max_tx_urbs * sizeof(*priv->tx_contexts),
+			      dev->max_tx_urbs);
+	if (!netdev) {
+		dev_err(&dev->intf->dev, "Cannot alloc candev\n");
+		return -ENOMEM;
+	}
+
+	priv = netdev_priv(netdev);
+
+	init_usb_anchor(&priv->tx_submitted);
+	init_completion(&priv->start_comp);
+	init_completion(&priv->stop_comp);
+	priv->can.ctrlmode_supported = 0;
+
+	priv->dev = dev;
+	priv->netdev = netdev;
+	priv->channel = channel;
+
+	spin_lock_init(&priv->tx_contexts_lock);
+	kvaser_usb_reset_tx_urb_contexts(priv);
+
+	priv->can.state = CAN_STATE_STOPPED;
+	priv->can.clock.freq = dev->cfg->clock.freq;
+	priv->can.bittiming_const = dev->cfg->bittiming_const;
+	priv->can.do_set_bittiming = dev->ops->dev_set_bittiming;
+	priv->can.do_set_mode = dev->ops->dev_set_mode;
+	if (id->driver_info & KVASER_USB_HAS_TXRX_ERRORS)
+		priv->can.do_get_berr_counter = dev->ops->dev_get_berr_counter;
+	if (id->driver_info & KVASER_USB_HAS_SILENT_MODE)
+		priv->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY;
+
+	priv->can.ctrlmode_supported |= dev->card_data.ctrlmode_supported;
+
+	netdev->flags |= IFF_ECHO;
+
+	netdev->netdev_ops = &kvaser_usb_netdev_ops;
+
+	SET_NETDEV_DEV(netdev, &dev->intf->dev);
+	netdev->dev_id = channel;
+
+	dev->nets[channel] = priv;
+
+	err = register_candev(netdev);
+	if (err) {
+		dev_err(&dev->intf->dev, "Failed to register CAN device\n");
+		free_candev(netdev);
+		dev->nets[channel] = NULL;
+		return err;
+	}
+
+	netdev_dbg(netdev, "device registered\n");
+
+	return 0;
+}
+
+static int kvaser_usb_probe(struct usb_interface *intf,
+			    const struct usb_device_id *id)
+{
+	struct kvaser_usb *dev;
+	int err;
+	int i;
+
+	dev = devm_kzalloc(&intf->dev, sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return -ENOMEM;
+
+	if (kvaser_is_leaf(id)) {
+		dev->card_data.leaf.family = KVASER_LEAF;
+		dev->ops = &kvaser_usb_leaf_dev_ops;
+	} else if (kvaser_is_usbcan(id)) {
+		dev->card_data.leaf.family = KVASER_USBCAN;
+		dev->ops = &kvaser_usb_leaf_dev_ops;
+	} else {
+		dev_err(&intf->dev,
+			"Product ID (%d) is not a supported Kvaser USB device\n",
+			id->idProduct);
+		return -ENODEV;
+	}
+
+	dev->intf = intf;
+
+	err = dev->ops->dev_setup_endpoints(dev);
+	if (err) {
+		dev_err(&intf->dev, "Cannot get usb endpoint(s)");
+		return err;
+	}
+
+	dev->udev = interface_to_usbdev(intf);
+
+	init_usb_anchor(&dev->rx_submitted);
+
+	usb_set_intfdata(intf, dev);
+
+	dev->card_data.ctrlmode_supported = 0;
+	err = dev->ops->dev_init_card(dev);
+	if (err) {
+		dev_err(&intf->dev,
+			"Failed to initialize card, error %d\n", err);
+		return err;
+	}
+
+	err = dev->ops->dev_get_software_info(dev);
+	if (err) {
+		dev_err(&intf->dev,
+			"Cannot get software info, error %d\n", err);
+		return err;
+	}
+
+	if (WARN_ON(!dev->cfg))
+		return -ENODEV;
+
+	dev_dbg(&intf->dev, "Firmware version: %d.%d.%d\n",
+		((dev->fw_version >> 24) & 0xff),
+		((dev->fw_version >> 16) & 0xff),
+		(dev->fw_version & 0xffff));
+
+	dev_dbg(&intf->dev, "Max outstanding tx = %d URBs\n", dev->max_tx_urbs);
+
+	err = dev->ops->dev_get_card_info(dev);
+	if (err) {
+		dev_err(&intf->dev, "Cannot get card info, error %d\n", err);
+		return err;
+	}
+
+	for (i = 0; i < dev->nchannels; i++) {
+		err = kvaser_usb_init_one(dev, id, i);
+		if (err) {
+			kvaser_usb_remove_interfaces(dev);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
+static void kvaser_usb_disconnect(struct usb_interface *intf)
+{
+	struct kvaser_usb *dev = usb_get_intfdata(intf);
+
+	usb_set_intfdata(intf, NULL);
+
+	if (!dev)
+		return;
+
+	kvaser_usb_remove_interfaces(dev);
+}
+
+static struct usb_driver kvaser_usb_driver = {
+	.name = "kvaser_usb",
+	.probe = kvaser_usb_probe,
+	.disconnect = kvaser_usb_disconnect,
+	.id_table = kvaser_usb_table,
+};
+
+module_usb_driver(kvaser_usb_driver);
+
+MODULE_AUTHOR("Olivier Sobrie <[e-mail]>");
+MODULE_AUTHOR("Kvaser AB <[e-mail]>");
+MODULE_DESCRIPTION("CAN driver for Kvaser CAN/USB devices");
+MODULE_LICENSE("GPL v2");

drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c

···
+// SPDX-License-Identifier: GPL-2.0
+/* Parts of this driver are based on the following:
+ *  - Kvaser linux leaf driver (version 4.78)
+ *  - CAN driver for esd CAN-USB/2
+ *  - Kvaser linux usbcanII driver (version 5.3)
+ *
+ * Copyright (C) 2002-2018 KVASER AB, Sweden. All rights reserved.
+ * Copyright (C) 2010 Matthias Fuchs <[e-mail]>, esd gmbh
+ * Copyright (C) 2012 Olivier Sobrie <[e-mail]>
+ * Copyright (C) 2015 Valeo S.A.
+ */
+
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/gfp.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/usb.h>
+
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+#include <linux/can/netlink.h>
+
+#include "kvaser_usb.h"
+
+/* Forward declaration */
+static const struct kvaser_usb_dev_cfg kvaser_usb_leaf_dev_cfg;
+
+#define CAN_USB_CLOCK			8000000
+#define MAX_USBCAN_NET_DEVICES		2
+
+/* Command header size */
+#define CMD_HEADER_LEN			2
+
+/* Kvaser CAN message flags */
+#define MSG_FLAG_ERROR_FRAME		BIT(0)
+#define MSG_FLAG_OVERRUN		BIT(1)
+#define MSG_FLAG_NERR			BIT(2)
+#define MSG_FLAG_WAKEUP			BIT(3)
+#define MSG_FLAG_REMOTE_FRAME		BIT(4)
+#define MSG_FLAG_RESERVED		BIT(5)
+#define MSG_FLAG_TX_ACK			BIT(6)
+#define MSG_FLAG_TX_REQUEST		BIT(7)
+
+/* CAN states (M16C CxSTRH register) */
+#define M16C_STATE_BUS_RESET		BIT(0)
+#define M16C_STATE_BUS_ERROR		BIT(4)
+#define M16C_STATE_BUS_PASSIVE		BIT(5)
+#define M16C_STATE_BUS_OFF		BIT(6)
+
+/* Leaf/usbcan command ids */
+#define CMD_RX_STD_MESSAGE		12
+#define CMD_TX_STD_MESSAGE		13
+#define CMD_RX_EXT_MESSAGE		14
+#define CMD_TX_EXT_MESSAGE		15
+#define CMD_SET_BUS_PARAMS		16
+#define CMD_CHIP_STATE_EVENT		20
+#define CMD_SET_CTRL_MODE		21
+#define CMD_RESET_CHIP			24
+#define CMD_START_CHIP			26
+#define CMD_START_CHIP_REPLY		27
+#define CMD_STOP_CHIP			28
+#define CMD_STOP_CHIP_REPLY		29
+
+#define CMD_USBCAN_CLOCK_OVERFLOW_EVENT	33
+
+#define CMD_GET_CARD_INFO		34
+#define CMD_GET_CARD_INFO_REPLY		35
+#define CMD_GET_SOFTWARE_INFO		38
+#define CMD_GET_SOFTWARE_INFO_REPLY	39
+#define CMD_FLUSH_QUEUE			48
+#define CMD_TX_ACKNOWLEDGE		50
+#define CMD_CAN_ERROR_EVENT		51
+#define CMD_FLUSH_QUEUE_REPLY		68
+
+#define CMD_LEAF_LOG_MESSAGE		106
+
+/* error factors */
+#define M16C_EF_ACKE			BIT(0)
+#define M16C_EF_CRCE			BIT(1)
+#define M16C_EF_FORME			BIT(2)
+#define M16C_EF_STFE			BIT(3)
+#define M16C_EF_BITE0			BIT(4)
+#define M16C_EF_BITE1			BIT(5)
+#define M16C_EF_RCVE			BIT(6)
+#define M16C_EF_TRE			BIT(7)
+
+/* Only Leaf-based devices can report M16C error factors,
+ * thus define our own error status flags for USBCANII
+ */
+#define USBCAN_ERROR_STATE_NONE		0
+#define USBCAN_ERROR_STATE_TX_ERROR	BIT(0)
+#define USBCAN_ERROR_STATE_RX_ERROR	BIT(1)
+#define USBCAN_ERROR_STATE_BUSERROR	BIT(2)
+
+/* bittiming parameters */
+#define KVASER_USB_TSEG1_MIN		1
+#define KVASER_USB_TSEG1_MAX		16
+#define KVASER_USB_TSEG2_MIN		1
+#define KVASER_USB_TSEG2_MAX		8
+#define KVASER_USB_SJW_MAX		4
+#define KVASER_USB_BRP_MIN		1
+#define KVASER_USB_BRP_MAX		64
+#define KVASER_USB_BRP_INC		1
+
+/* ctrl modes */
+#define KVASER_CTRL_MODE_NORMAL		1
+#define KVASER_CTRL_MODE_SILENT		2
+#define KVASER_CTRL_MODE_SELFRECEPTION	3
+#define KVASER_CTRL_MODE_OFF		4
+
+/* Extended CAN identifier flag */
+#define KVASER_EXTENDED_FRAME		BIT(31)
+
+struct kvaser_cmd_simple {
+	u8 tid;
+	u8 channel;
+} __packed;
+
+struct kvaser_cmd_cardinfo {
+	u8 tid;
+	u8 nchannels;
+	union {
+		struct {
+			__le32 serial_number;
+			__le32 padding;
+		} __packed leaf0;
+		struct {
+			__le32 serial_number_low;
+			__le32 serial_number_high;
+		} __packed usbcan0;
+	} __packed;
+	__le32 clock_resolution;
+	__le32 mfgdate;
+	u8 ean[8];
+	u8 hw_revision;
+	union {
+		struct {
+			u8 usb_hs_mode;
+		} __packed leaf1;
+		struct {
+			u8 padding;
+		} __packed usbcan1;
+	} __packed;
+	__le16 padding;
+} __packed;
+
+struct leaf_cmd_softinfo {
+	u8 tid;
+	u8 padding0;
+	__le32 sw_options;
+	__le32 fw_version;
+	__le16 max_outstanding_tx;
+	__le16 padding1[9];
+} __packed;
+
+struct usbcan_cmd_softinfo {
+	u8 tid;
+	u8 fw_name[5];
+	__le16 max_outstanding_tx;
+	u8 padding[6];
+	__le32 fw_version;
+	__le16 checksum;
+	__le16 sw_options;
+} __packed;
+
+struct kvaser_cmd_busparams {
+	u8 tid;
+	u8 channel;
+	__le32 bitrate;
+	u8 tseg1;
+	u8 tseg2;
+	u8 sjw;
+	u8 no_samp;
+} __packed;
+
+struct kvaser_cmd_tx_can {
+	u8 channel;
+	u8 tid;
+	u8 data[14];
+	union {
+		struct {
+			u8 padding;
+			u8 flags;
+		} __packed leaf;
+		struct {
+			u8 flags;
+			u8 padding;
+		} __packed usbcan;
+	} __packed;
+} __packed;
+
+struct kvaser_cmd_rx_can_header {
+	u8 channel;
+	u8 flag;
+} __packed;
+
+struct leaf_cmd_rx_can {
+	u8 channel;
+	u8 flag;
+
+	__le16 time[3];
+	u8 data[14];
+} __packed;
+
+struct usbcan_cmd_rx_can {
+	u8 channel;
+	u8 flag;
+
+	u8 data[14];
+	__le16 time;
+} __packed;
+
+struct leaf_cmd_chip_state_event {
+	u8 tid;
+	u8 channel;
+
+	__le16 time[3];
+	u8 tx_errors_count;
+	u8 rx_errors_count;
+
+	u8 status;
+	u8 padding[3];
+} __packed;
+
+struct usbcan_cmd_chip_state_event {
+	u8 tid;
+	u8 channel;
+
+	u8 tx_errors_count;
+	u8 rx_errors_count;
+	__le16 time;
+
+	u8 status;
+	u8 padding[3];
+} __packed;
+
+struct kvaser_cmd_tx_acknowledge_header {
+	u8 channel;
+	u8 tid;
+} __packed;
+
+struct leaf_cmd_error_event {
+	u8 tid;
+	u8 flags;
+	__le16 time[3];
+	u8 channel;
+	u8 padding;
+	u8 tx_errors_count;
+	u8 rx_errors_count;
+	u8 status;
+	u8 error_factor;
+} __packed;
+
+struct usbcan_cmd_error_event {
+	u8 tid;
+	u8 padding;
+	u8 tx_errors_count_ch0;
+	u8 rx_errors_count_ch0;
+	u8 tx_errors_count_ch1;
+	u8 rx_errors_count_ch1;
+	u8 status_ch0;
+	u8 status_ch1;
+	__le16 time;
+} __packed;
+
+struct kvaser_cmd_ctrl_mode {
+	u8 tid;
+	u8 channel;
+	u8 ctrl_mode;
+	u8 padding[3];
+} __packed;
+
+struct kvaser_cmd_flush_queue {
+	u8 tid;
+	u8 channel;
+	u8 flags;
+	u8 padding[3];
+} __packed;
+
+struct leaf_cmd_log_message {
+	u8 channel;
+	u8 flags;
+	__le16 time[3];
+	u8 dlc;
+	u8 time_offset;
+	__le32 id;
+	u8 data[8];
+} __packed;
+
+struct kvaser_cmd {
+	u8 len;
+	u8 id;
+	union	{
+		struct kvaser_cmd_simple simple;
+		struct kvaser_cmd_cardinfo cardinfo;
+		struct kvaser_cmd_busparams busparams;
+
+		struct kvaser_cmd_rx_can_header rx_can_header;
+		struct kvaser_cmd_tx_acknowledge_header tx_acknowledge_header;
+
+		union {
+			struct leaf_cmd_softinfo softinfo;
+			struct leaf_cmd_rx_can rx_can;
+			struct leaf_cmd_chip_state_event chip_state_event;
+			struct leaf_cmd_error_event error_event;
+			struct leaf_cmd_log_message log_message;
+		} __packed leaf;
+
+		union {
+			struct usbcan_cmd_softinfo softinfo;
+			struct usbcan_cmd_rx_can rx_can;
+			struct usbcan_cmd_chip_state_event chip_state_event;
+			struct usbcan_cmd_error_event error_event;
+		} __packed usbcan;
+
+		struct kvaser_cmd_tx_can tx_can;
+		struct kvaser_cmd_ctrl_mode ctrl_mode;
+		struct kvaser_cmd_flush_queue flush_queue;
+	} u;
+} __packed;
+
+/* Summary of a kvaser error event, for a unified Leaf/Usbcan error
+ * handling. Some discrepancies between the two families exist:
+ *
+ * - USBCAN firmware does not report M16C "error factors"
+ * - USBCAN controllers has difficulties reporting if the raised error
+ *   event is for ch0 or ch1. They leave such arbitration to the OS
+ *   driver by letting it compare error counters with previous values
+ *   and decide the error event's channel. Thus for USBCAN, the channel
+ *   field is only advisory.
+ */
+struct kvaser_usb_err_summary {
+	u8 channel, status, txerr, rxerr;
+	union {
+		struct {
+			u8 error_factor;
+		} leaf;
+		struct {
+			u8 other_ch_status;
+			u8 error_state;
+		} usbcan;
+	};
+};
+
+static void *
+kvaser_usb_leaf_frame_to_cmd(const struct kvaser_usb_net_priv *priv,
+			     const struct sk_buff *skb, int *frame_len,
+			     int *cmd_len, u16 transid)
+{
+	struct kvaser_usb *dev = priv->dev;
+	struct kvaser_cmd *cmd;
+	u8 *cmd_tx_can_flags = NULL;		/* GCC */
+	struct can_frame *cf = (struct can_frame *)skb->data;
+
+	*frame_len = cf->can_dlc;
+
+	cmd = kmalloc(sizeof(*cmd), GFP_ATOMIC);
+	if (cmd) {
+		cmd->u.tx_can.tid = transid & 0xff;
+		cmd->len = *cmd_len = CMD_HEADER_LEN +
+				      sizeof(struct kvaser_cmd_tx_can);
+		cmd->u.tx_can.channel = priv->channel;
+
+		switch (dev->card_data.leaf.family) {
+		case KVASER_LEAF:
+			cmd_tx_can_flags = &cmd->u.tx_can.leaf.flags;
+			break;
+		case KVASER_USBCAN:
+			cmd_tx_can_flags = &cmd->u.tx_can.usbcan.flags;
+			break;
+		}
+
+		*cmd_tx_can_flags = 0;
+
+		if (cf->can_id & CAN_EFF_FLAG) {
+			cmd->id = CMD_TX_EXT_MESSAGE;
+			cmd->u.tx_can.data[0] = (cf->can_id >> 24) & 0x1f;
+			cmd->u.tx_can.data[1] = (cf->can_id >> 18) & 0x3f;
+			cmd->u.tx_can.data[2] = (cf->can_id >> 14) & 0x0f;
+			cmd->u.tx_can.data[3] = (cf->can_id >> 6) & 0xff;
+			cmd->u.tx_can.data[4] = cf->can_id & 0x3f;
+		} else {
+			cmd->id = CMD_TX_STD_MESSAGE;
+			cmd->u.tx_can.data[0] = (cf->can_id >> 6) & 0x1f;
+			cmd->u.tx_can.data[1] = cf->can_id & 0x3f;
+		}
+
+		cmd->u.tx_can.data[5] = cf->can_dlc;
+		memcpy(&cmd->u.tx_can.data[6], cf->data, cf->can_dlc);
+
+		if (cf->can_id & CAN_RTR_FLAG)
+			*cmd_tx_can_flags |= MSG_FLAG_REMOTE_FRAME;
+	}
+	return cmd;
+}
+
+static int kvaser_usb_leaf_wait_cmd(const struct kvaser_usb *dev, u8 id,
+				    struct kvaser_cmd *cmd)
+{
+	struct kvaser_cmd *tmp;
+	void *buf;
+	int actual_len;
+	int err;
+	int pos;
+	unsigned long to = jiffies + msecs_to_jiffies(KVASER_USB_TIMEOUT);
+
+	buf = kzalloc(KVASER_USB_RX_BUFFER_SIZE, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	do {
+		err = kvaser_usb_recv_cmd(dev, buf, KVASER_USB_RX_BUFFER_SIZE,
+					  &actual_len);
+		if (err < 0)
+			goto end;
+
+		pos = 0;
+		while (pos <= actual_len - CMD_HEADER_LEN) {
+			tmp = buf + pos;
+
+			/* Handle commands crossing the USB endpoint max packet
+			 * size boundary. Check kvaser_usb_read_bulk_callback()
+			 * for further details.
+			 */
+			if (tmp->len == 0) {
+				pos = round_up(pos,
+					       le16_to_cpu
+						(dev->bulk_in->wMaxPacketSize));
+				continue;
+			}
+
+			if (pos + tmp->len > actual_len) {
+				dev_err_ratelimited(&dev->intf->dev,
+						    "Format error\n");
+				break;
+			}
+
+			if (tmp->id == id) {
+				memcpy(cmd, tmp, tmp->len);
+				goto end;
+			}
+
+			pos += tmp->len;
+		}
+	} while (time_before(jiffies, to));
+
+	err = -EINVAL;
+
+end:
+	kfree(buf);
+
+	return err;
+}
+
+static int kvaser_usb_leaf_send_simple_cmd(const struct kvaser_usb *dev,
+					   u8 cmd_id, int channel)
+{
+	struct kvaser_cmd *cmd;
+	int rc;
+
+	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
+	if (!cmd)
+		return -ENOMEM;
+
+	cmd->id = cmd_id;
+	cmd->len = CMD_HEADER_LEN + sizeof(struct kvaser_cmd_simple);
+	cmd->u.simple.channel = channel;
+	cmd->u.simple.tid = 0xff;
+
+	rc = kvaser_usb_send_cmd(dev, cmd, cmd->len);
+
+	kfree(cmd);
+	return rc;
+}
+
+static int kvaser_usb_leaf_get_software_info_inner(struct kvaser_usb *dev)
+{
+	struct kvaser_cmd cmd;
+	int err;
+
+	err = kvaser_usb_leaf_send_simple_cmd(dev, CMD_GET_SOFTWARE_INFO, 0);
+	if (err)
+		return err;
+
+	err = kvaser_usb_leaf_wait_cmd(dev, CMD_GET_SOFTWARE_INFO_REPLY, &cmd);
+	if (err)
+		return err;
+
+	switch (dev->card_data.leaf.family) {
+	case KVASER_LEAF:
+		dev->fw_version = le32_to_cpu(cmd.u.leaf.softinfo.fw_version);
+		dev->max_tx_urbs =
+			le16_to_cpu(cmd.u.leaf.softinfo.max_outstanding_tx);
+		break;
+	case KVASER_USBCAN:
+		dev->fw_version = le32_to_cpu(cmd.u.usbcan.softinfo.fw_version);
+		dev->max_tx_urbs =
+			le16_to_cpu(cmd.u.usbcan.softinfo.max_outstanding_tx);
+		break;
+	}
+
+	return 0;
+}
+
+static int kvaser_usb_leaf_get_software_info(struct kvaser_usb *dev)
+{
+	int err;
+	int retry = 3;
+
+	/* On some x86 laptops, plugging a Kvaser device again after
+	 * an unplug makes the firmware always ignore the very first
+	 * command. For such a case, provide some room for retries
+	 * instead of completely exiting the driver.
+	 */
+	do {
+		err = kvaser_usb_leaf_get_software_info_inner(dev);
+	} while (--retry && err == -ETIMEDOUT);
+
+	return err;
+}
+
+static int kvaser_usb_leaf_get_card_info(struct kvaser_usb *dev)
+{
+	struct kvaser_cmd cmd;
+	int err;
+
+	err = kvaser_usb_leaf_send_simple_cmd(dev, CMD_GET_CARD_INFO, 0);
+	if (err)
+		return err;
+
+	err = kvaser_usb_leaf_wait_cmd(dev, CMD_GET_CARD_INFO_REPLY, &cmd);
+	if (err)
+		return err;
+
+	dev->nchannels = cmd.u.cardinfo.nchannels;
+	if (dev->nchannels > KVASER_USB_MAX_NET_DEVICES ||
+	    (dev->card_data.leaf.family == KVASER_USBCAN &&
+	     dev->nchannels > MAX_USBCAN_NET_DEVICES))
+		return -EINVAL;
+
+	return 0;
+}
+
+static void kvaser_usb_leaf_tx_acknowledge(const struct kvaser_usb *dev,
+					   const struct kvaser_cmd *cmd)
+{
+	struct net_device_stats *stats;
+	struct kvaser_usb_tx_urb_context *context;
+	struct kvaser_usb_net_priv *priv;
+	unsigned long flags;
+	u8 channel, tid;
+
+	channel = cmd->u.tx_acknowledge_header.channel;
+	tid = cmd->u.tx_acknowledge_header.tid;
+
+	if (channel >= dev->nchannels) {
+		dev_err(&dev->intf->dev,
+			"Invalid channel number (%d)\n", channel);
+		return;
+	}
+
+	priv = dev->nets[channel];
+
+	if (!netif_device_present(priv->netdev))
+		return;
+
+	stats = &priv->netdev->stats;
+
+	context = &priv->tx_contexts[tid % dev->max_tx_urbs];
+
+	/* Sometimes the state change doesn't come after a bus-off event */
+	if (priv->can.restart_ms && priv->can.state >= CAN_STATE_BUS_OFF) {
+		struct sk_buff *skb;
+		struct can_frame *cf;
+
+		skb = alloc_can_err_skb(priv->netdev, &cf);
+		if (skb) {
+			cf->can_id |= CAN_ERR_RESTARTED;
+
+			stats->rx_packets++;
+			stats->rx_bytes += cf->can_dlc;
+			netif_rx(skb);
+		} else {
+			netdev_err(priv->netdev,
+				   "No memory left for err_skb\n");
+		}
+
+		priv->can.can_stats.restarts++;
+		netif_carrier_on(priv->netdev);
+
+		priv->can.state = CAN_STATE_ERROR_ACTIVE;
+	}
+
+	stats->tx_packets++;
+	stats->tx_bytes += context->dlc;
+
+	spin_lock_irqsave(&priv->tx_contexts_lock, flags);
+
+	can_get_echo_skb(priv->netdev, context->echo_index);
+	context->echo_index = dev->max_tx_urbs;
+	--priv->active_tx_contexts;
+	netif_wake_queue(priv->netdev);
+
+	spin_unlock_irqrestore(&priv->tx_contexts_lock, flags);
+}
+
+static int kvaser_usb_leaf_simple_cmd_async(struct kvaser_usb_net_priv *priv,
+					    u8 cmd_id)
+{
+	struct kvaser_cmd *cmd;
+	int err;
+
+	cmd = kmalloc(sizeof(*cmd), GFP_ATOMIC);
+	if (!cmd)
+		return -ENOMEM;
+
+	cmd->len = CMD_HEADER_LEN + sizeof(struct kvaser_cmd_simple);
+	cmd->id = cmd_id;
+	cmd->u.simple.channel = priv->channel;
+
+	err = kvaser_usb_send_cmd_async(priv, cmd, cmd->len);
+	if (err)
+		kfree(cmd);
+
+	return err;
+}
+
+static void
+kvaser_usb_leaf_rx_error_update_can_state(struct kvaser_usb_net_priv *priv,
+					const struct kvaser_usb_err_summary *es,
+					struct can_frame *cf)
+{
+	struct kvaser_usb *dev = priv->dev;
+	struct net_device_stats *stats = &priv->netdev->stats;
+	enum can_state cur_state, new_state, tx_state, rx_state;
+
+	netdev_dbg(priv->netdev, "Error status: 0x%02x\n", es->status);
+
+	new_state = priv->can.state;
+	cur_state = priv->can.state;
+
+	if (es->status & (M16C_STATE_BUS_OFF | M16C_STATE_BUS_RESET)) {
+		new_state = CAN_STATE_BUS_OFF;
+	} else if (es->status & M16C_STATE_BUS_PASSIVE) {
+		new_state = CAN_STATE_ERROR_PASSIVE;
+	} else if (es->status & M16C_STATE_BUS_ERROR) {
+		/* Guard against spurious error events after a busoff */
+		if (cur_state < CAN_STATE_BUS_OFF) {
+			if (es->txerr >= 128 || es->rxerr >= 128)
+				new_state = CAN_STATE_ERROR_PASSIVE;
+			else if (es->txerr >= 96 || es->rxerr >= 96)
+				new_state = CAN_STATE_ERROR_WARNING;
+			else if (cur_state > CAN_STATE_ERROR_ACTIVE)
+				new_state = CAN_STATE_ERROR_ACTIVE;
+		}
+	}
+
+	if (!es->status)
+		new_state = CAN_STATE_ERROR_ACTIVE;
+
+	if (new_state != cur_state) {
+		tx_state = (es->txerr >= es->rxerr) ? new_state : 0;
+		rx_state = (es->txerr <= es->rxerr) ? new_state : 0;
+
+		can_change_state(priv->netdev, cf, tx_state, rx_state);
+	}
+
+	if (priv->can.restart_ms &&
+	    cur_state >= CAN_STATE_BUS_OFF &&
+	    new_state < CAN_STATE_BUS_OFF)
+		priv->can.can_stats.restarts++;
+
+	switch (dev->card_data.leaf.family) {
+	case KVASER_LEAF:
+		if (es->leaf.error_factor) {
+			priv->can.can_stats.bus_error++;
+			stats->rx_errors++;
+		}
+		break;
+	case KVASER_USBCAN:
+		if (es->usbcan.error_state & USBCAN_ERROR_STATE_TX_ERROR)
+			stats->tx_errors++;
+		if (es->usbcan.error_state & USBCAN_ERROR_STATE_RX_ERROR)
+			stats->rx_errors++;
+		if (es->usbcan.error_state & USBCAN_ERROR_STATE_BUSERROR)
+			priv->can.can_stats.bus_error++;
+		break;
+	}
+
+	priv->bec.txerr = es->txerr;
+	priv->bec.rxerr = es->rxerr;
+}
+
+static void kvaser_usb_leaf_rx_error(const struct kvaser_usb *dev,
+				     const struct kvaser_usb_err_summary *es)
+{
+	struct can_frame *cf;
+	struct can_frame tmp_cf = { .can_id = CAN_ERR_FLAG,
+				    .can_dlc = CAN_ERR_DLC };
+	struct sk_buff *skb;
+	struct net_device_stats *stats;
+	struct kvaser_usb_net_priv *priv;
+	enum can_state old_state, new_state;
+
+	if (es->channel >= dev->nchannels) {
+		dev_err(&dev->intf->dev,
+			"Invalid channel number (%d)\n", es->channel);
+		return;
+	}
+
+	priv = dev->nets[es->channel];
+	stats = &priv->netdev->stats;
+
+	/* Update all of the CAN interface's state and error counters before
+	 * trying any memory allocation that can actually fail with -ENOMEM.
+	 *
+	 * We send a temporary stack-allocated error CAN frame to
+	 * can_change_state() for the very same reason.
+	 *
+	 * TODO: Split can_change_state() responsibility between updating the
+	 * CAN interface's state and counters, and the setting up of CAN error
+	 * frame ID and data to userspace. Remove stack allocation afterwards.
+	 */
+	old_state = priv->can.state;
+	kvaser_usb_leaf_rx_error_update_can_state(priv, es, &tmp_cf);
+	new_state = priv->can.state;
+
+	skb = alloc_can_err_skb(priv->netdev, &cf);
+	if (!skb) {
+		stats->rx_dropped++;
+		return;
+	}
+	memcpy(cf, &tmp_cf, sizeof(*cf));
+
+	if (new_state != old_state) {
+		if (es->status &
+		    (M16C_STATE_BUS_OFF | M16C_STATE_BUS_RESET)) {
+			if (!priv->can.restart_ms)
+				kvaser_usb_leaf_simple_cmd_async(priv,
+								 CMD_STOP_CHIP);
+			netif_carrier_off(priv->netdev);
+		}
+
+		if (priv->can.restart_ms &&
+		    old_state >= CAN_STATE_BUS_OFF &&
+		    new_state < CAN_STATE_BUS_OFF) {
+			cf->can_id |= CAN_ERR_RESTARTED;
+			netif_carrier_on(priv->netdev);
+		}
+	}
+
+	switch (dev->card_data.leaf.family) {
+	case KVASER_LEAF:
+		if (es->leaf.error_factor) {
+			cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_PROT;
+
+			if (es->leaf.error_factor & M16C_EF_ACKE)
+				cf->data[3] = CAN_ERR_PROT_LOC_ACK;
+			if (es->leaf.error_factor & M16C_EF_CRCE)
+				cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
+			if (es->leaf.error_factor & M16C_EF_FORME)
+				cf->data[2] |= CAN_ERR_PROT_FORM;
+			if (es->leaf.error_factor & M16C_EF_STFE)
+				cf->data[2] |= CAN_ERR_PROT_STUFF;
+			if (es->leaf.error_factor & M16C_EF_BITE0)
+				cf->data[2] |= CAN_ERR_PROT_BIT0;
+			if (es->leaf.error_factor & M16C_EF_BITE1)
+				cf->data[2] |= CAN_ERR_PROT_BIT1;
+			if (es->leaf.error_factor & M16C_EF_TRE)
+				cf->data[2] |= CAN_ERR_PROT_TX;
+		}
+		break;
+	case KVASER_USBCAN:
+		if (es->usbcan.error_state & USBCAN_ERROR_STATE_BUSERROR)
+			cf->can_id |= CAN_ERR_BUSERROR;
+		break;
+	}
+
+	cf->data[6] = es->txerr;
+	cf->data[7] = es->rxerr;
+
+	stats->rx_packets++;
+	stats->rx_bytes += cf->can_dlc;
+	netif_rx(skb);
+}
+
+/* For USBCAN, report error to userspace if the channels's errors counter
+ * has changed, or we're the only channel seeing a bus error state.
+ */
+static void
+kvaser_usb_leaf_usbcan_conditionally_rx_error(const struct kvaser_usb *dev,
+					      struct kvaser_usb_err_summary *es)
+{
+	struct kvaser_usb_net_priv *priv;
+	unsigned int channel;
+	bool report_error;
+
+	channel = es->channel;
+	if (channel >= dev->nchannels) {
+		dev_err(&dev->intf->dev,
+			"Invalid channel number (%d)\n", channel);
+		return;
+	}
+
+	priv = dev->nets[channel];
+	report_error = false;
+
+	if (es->txerr != priv->bec.txerr) {
+		es->usbcan.error_state |= USBCAN_ERROR_STATE_TX_ERROR;
+		report_error = true;
+	}
+	if (es->rxerr != priv->bec.rxerr) {
+		es->usbcan.error_state |= USBCAN_ERROR_STATE_RX_ERROR;
+		report_error = true;
+	}
+	if ((es->status & M16C_STATE_BUS_ERROR) &&
+	    !(es->usbcan.other_ch_status & M16C_STATE_BUS_ERROR)) {
+		es->usbcan.error_state |= USBCAN_ERROR_STATE_BUSERROR;
+		report_error = true;
+	}
+
+	if (report_error)
+		kvaser_usb_leaf_rx_error(dev, es);
+}
+
+static void kvaser_usb_leaf_usbcan_rx_error(const struct kvaser_usb *dev,
+					    const struct kvaser_cmd *cmd)
+{
+	struct kvaser_usb_err_summary es = { };
+
+	switch (cmd->id) {
+	/* Sometimes errors are sent as unsolicited chip state events */
+	case CMD_CHIP_STATE_EVENT:
+		es.channel = cmd->u.usbcan.chip_state_event.channel;
+		es.status = cmd->u.usbcan.chip_state_event.status;
+		es.txerr = cmd->u.usbcan.chip_state_event.tx_errors_count;
+		es.rxerr = cmd->u.usbcan.chip_state_event.rx_errors_count;
+		kvaser_usb_leaf_usbcan_conditionally_rx_error(dev, &es);
+		break;
+
+	case CMD_CAN_ERROR_EVENT:
+		es.channel = 0;
+		es.status = cmd->u.usbcan.error_event.status_ch0;
+		es.txerr = cmd->u.usbcan.error_event.tx_errors_count_ch0;
+		es.rxerr = cmd->u.usbcan.error_event.rx_errors_count_ch0;
+		es.usbcan.other_ch_status =
+			cmd->u.usbcan.error_event.status_ch1;
+		kvaser_usb_leaf_usbcan_conditionally_rx_error(dev, &es);
+
+		/* The USBCAN firmware supports up to 2 channels.
+		 * Now that ch0 was checked, check if ch1 has any errors.
+		 */
+		if (dev->nchannels == MAX_USBCAN_NET_DEVICES) {
+			es.channel = 1;
+			es.status = cmd->u.usbcan.error_event.status_ch1;
+			es.txerr =
+				cmd->u.usbcan.error_event.tx_errors_count_ch1;
+			es.rxerr =
+				cmd->u.usbcan.error_event.rx_errors_count_ch1;
+			es.usbcan.other_ch_status =
+				cmd->u.usbcan.error_event.status_ch0;
+			kvaser_usb_leaf_usbcan_conditionally_rx_error(dev, &es);
+		}
+		break;
+
+	default:
+		dev_err(&dev->intf->dev, "Invalid cmd id (%d)\n", cmd->id);
+	}
+}
+
+static void kvaser_usb_leaf_leaf_rx_error(const struct kvaser_usb *dev,
+					  const struct kvaser_cmd *cmd)
+{
+	struct kvaser_usb_err_summary es = { };
+
+	switch (cmd->id) {
+	case CMD_CAN_ERROR_EVENT:
+		es.channel = cmd->u.leaf.error_event.channel;
+		es.status = cmd->u.leaf.error_event.status;
+		es.txerr = cmd->u.leaf.error_event.tx_errors_count;
+		es.rxerr = cmd->u.leaf.error_event.rx_errors_count;
+		es.leaf.error_factor = cmd->u.leaf.error_event.error_factor;
+		break;
+	case CMD_LEAF_LOG_MESSAGE:
+		es.channel = cmd->u.leaf.log_message.channel;
+		es.status = cmd->u.leaf.log_message.data[0];
+		es.txerr = cmd->u.leaf.log_message.data[2];
+		es.rxerr = cmd->u.leaf.log_message.data[3];
+		es.leaf.error_factor = cmd->u.leaf.log_message.data[1];
+		break;
+	case CMD_CHIP_STATE_EVENT:
+		es.channel = cmd->u.leaf.chip_state_event.channel;
+		es.status = cmd->u.leaf.chip_state_event.status;
+		es.txerr = cmd->u.leaf.chip_state_event.tx_errors_count;
+		es.rxerr = cmd->u.leaf.chip_state_event.rx_errors_count;
+		es.leaf.error_factor = 0;
+		break;
+	default:
+		dev_err(&dev->intf->dev, "Invalid cmd id (%d)\n", cmd->id);
+		return;
+	}
+
+	kvaser_usb_leaf_rx_error(dev, &es);
+}
+
+static void kvaser_usb_leaf_rx_can_err(const struct kvaser_usb_net_priv *priv,
+				       const struct kvaser_cmd *cmd)
+{
+	if (cmd->u.rx_can_header.flag & (MSG_FLAG_ERROR_FRAME |
+					 MSG_FLAG_NERR)) {
+		struct net_device_stats *stats = &priv->netdev->stats;
+
+		netdev_err(priv->netdev, "Unknown error (flags: 0x%02x)\n",
+			   cmd->u.rx_can_header.flag);
+
+		stats->rx_errors++;
+		return;
+	}
+
+	if (cmd->u.rx_can_header.flag & MSG_FLAG_OVERRUN)
+		kvaser_usb_can_rx_over_error(priv->netdev);
+}
+
+static void kvaser_usb_leaf_rx_can_msg(const struct kvaser_usb *dev,
+				       const struct kvaser_cmd *cmd)
+{
+	struct kvaser_usb_net_priv *priv;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+	struct net_device_stats *stats;
+	u8 channel = cmd->u.rx_can_header.channel;
+	const u8 *rx_data = NULL;	/* GCC */
+
+	if (channel >= dev->nchannels) {
+		dev_err(&dev->intf->dev,
+			"Invalid channel number (%d)\n", channel);
+		return;
+	}
+
+	priv = dev->nets[channel];
+	stats = &priv->netdev->stats;
+
+	if ((cmd->u.rx_can_header.flag & MSG_FLAG_ERROR_FRAME) &&
+	    (dev->card_data.leaf.family == KVASER_LEAF &&
+	     cmd->id == CMD_LEAF_LOG_MESSAGE)) {
+		kvaser_usb_leaf_leaf_rx_error(dev, cmd);
+		return;
+	} else if (cmd->u.rx_can_header.flag & (MSG_FLAG_ERROR_FRAME |
+						MSG_FLAG_NERR |
+						MSG_FLAG_OVERRUN)) {
+		kvaser_usb_leaf_rx_can_err(priv, cmd);
+		return;
+	} else if (cmd->u.rx_can_header.flag & ~MSG_FLAG_REMOTE_FRAME) {
+		netdev_warn(priv->netdev,
+			    "Unhandled frame (flags: 0x%02x)\n",
+			    cmd->u.rx_can_header.flag);
+		return;
+	}
+
+	switch (dev->card_data.leaf.family) {
+	case KVASER_LEAF:
+		rx_data = cmd->u.leaf.rx_can.data;
+		break;
+	case KVASER_USBCAN:
+		rx_data = cmd->u.usbcan.rx_can.data;
+		break;
+	}
+
+	skb = alloc_can_skb(priv->netdev, &cf);
+	if (!skb) {
+		stats->rx_dropped++;
+		return;
+	}
+
+	if (dev->card_data.leaf.family == KVASER_LEAF && cmd->id ==
+	    CMD_LEAF_LOG_MESSAGE) {
+		cf->can_id = le32_to_cpu(cmd->u.leaf.log_message.id);
+		if (cf->can_id & KVASER_EXTENDED_FRAME)
+			cf->can_id &= CAN_EFF_MASK | CAN_EFF_FLAG;
+		else
+			cf->can_id &= CAN_SFF_MASK;
+
+		cf->can_dlc = get_can_dlc(cmd->u.leaf.log_message.dlc);
+
+		if (cmd->u.leaf.log_message.flags & MSG_FLAG_REMOTE_FRAME)
+			cf->can_id |= CAN_RTR_FLAG;
+		else
+			memcpy(cf->data, &cmd->u.leaf.log_message.data,
+			       cf->can_dlc);
+	} else {
+		cf->can_id = ((rx_data[0] & 0x1f) << 6) | (rx_data[1] & 0x3f);
+
+		if (cmd->id == CMD_RX_EXT_MESSAGE) {
+			cf->can_id <<= 18;
+			cf->can_id |= ((rx_data[2] & 0x0f) << 14) |
+				      ((rx_data[3] & 0xff) << 6) |
+				      (rx_data[4] & 0x3f);
+			cf->can_id |= CAN_EFF_FLAG;
+		}
+
+		cf->can_dlc = get_can_dlc(rx_data[5]);
+
+		if (cmd->u.rx_can_header.flag & MSG_FLAG_REMOTE_FRAME)
+			cf->can_id |= CAN_RTR_FLAG;
+		else
+			memcpy(cf->data, &rx_data[6], cf->can_dlc);
+	}
+
+	stats->rx_packets++;
+	stats->rx_bytes += cf->can_dlc;
+	netif_rx(skb);
+}
+
+static void kvaser_usb_leaf_start_chip_reply(const struct kvaser_usb *dev,
+					     const struct kvaser_cmd *cmd)
+{
+	struct kvaser_usb_net_priv *priv;
+	u8 channel = cmd->u.simple.channel;
+
+	if (channel >= dev->nchannels) {
+		dev_err(&dev->intf->dev,
+			"Invalid channel number (%d)\n", channel);
+		return;
+	}
+
+	priv = dev->nets[channel];
+
+	if (completion_done(&priv->start_comp) &&
+	    netif_queue_stopped(priv->netdev)) {
+		netif_wake_queue(priv->netdev);
+	} else {
+		netif_start_queue(priv->netdev);
+		complete(&priv->start_comp);
+	}
+}
+
+static void kvaser_usb_leaf_stop_chip_reply(const struct kvaser_usb *dev,
+					    const struct kvaser_cmd *cmd)
+{
+	struct kvaser_usb_net_priv *priv;
+	u8 channel = cmd->u.simple.channel;
+
+	if (channel >= dev->nchannels) {
+		dev_err(&dev->intf->dev,
+			"Invalid channel number (%d)\n", channel);
+		return;
+	}
+
+	priv = dev->nets[channel];
+
+	complete(&priv->stop_comp);
+}
+
+static void kvaser_usb_leaf_handle_command(const struct kvaser_usb *dev,
+					   const struct kvaser_cmd *cmd)
+{
+	switch (cmd->id) {
+	case CMD_START_CHIP_REPLY:
+		kvaser_usb_leaf_start_chip_reply(dev, cmd);
+		break;
+
+	case CMD_STOP_CHIP_REPLY:
+		kvaser_usb_leaf_stop_chip_reply(dev, cmd);
+		break;
+
+	case CMD_RX_STD_MESSAGE:
+	case CMD_RX_EXT_MESSAGE:
+		kvaser_usb_leaf_rx_can_msg(dev, cmd);
+		break;
+
+	case CMD_LEAF_LOG_MESSAGE:
+		if (dev->card_data.leaf.family != KVASER_LEAF)
+			goto warn;
+		kvaser_usb_leaf_rx_can_msg(dev, cmd);
+		break;
+
+	case CMD_CHIP_STATE_EVENT:
+	case CMD_CAN_ERROR_EVENT:
+		if (dev->card_data.leaf.family == KVASER_LEAF)
+			kvaser_usb_leaf_leaf_rx_error(dev, cmd);
+		else
+			kvaser_usb_leaf_usbcan_rx_error(dev, cmd);
+		break;
+
+	case CMD_TX_ACKNOWLEDGE:
+		kvaser_usb_leaf_tx_acknowledge(dev, cmd);
+		break;
+
+	/* Ignored commands */
+	case CMD_USBCAN_CLOCK_OVERFLOW_EVENT:
+		if (dev->card_data.leaf.family != KVASER_USBCAN)
+			goto warn;
+		break;
+
+	case CMD_FLUSH_QUEUE_REPLY:
+		if (dev->card_data.leaf.family != KVASER_LEAF)
+			goto warn;
+		break;
+
+	default:
+warn:		dev_warn(&dev->intf->dev, "Unhandled command (%d)\n", cmd->id);
+		break;
+	}
+}
+
+static void kvaser_usb_leaf_read_bulk_callback(struct kvaser_usb *dev,
+					       void *buf, int len)
+{
+	struct kvaser_cmd *cmd;
+	int pos = 0;
+
+	while (pos <= len - CMD_HEADER_LEN) {
+		cmd = buf + pos;
+
+		/* The Kvaser firmware can only read and write commands that
+		 * does not cross the USB's endpoint wMaxPacketSize boundary.
+		 * If a follow-up command crosses such boundary, firmware puts
+		 * a placeholder zero-length command in its place then aligns
+		 * the real command to the next max packet size.
+		 *
+		 * Handle such cases or we're going to miss a significant
+		 * number of events in case of a heavy rx load on the bus.
+		 */
+		if (cmd->len == 0) {
+			pos = round_up(pos, le16_to_cpu
+						(dev->bulk_in->wMaxPacketSize));
+			continue;
+		}
+
+		if (pos + cmd->len > len) {
+			dev_err_ratelimited(&dev->intf->dev, "Format error\n");
+			break;
+		}
+
+		kvaser_usb_leaf_handle_command(dev, cmd);
+		pos += cmd->len;
+	}
+}
+
+static int kvaser_usb_leaf_set_opt_mode(const struct kvaser_usb_net_priv *priv)
+{
+	struct kvaser_cmd *cmd;
+	int rc;
+
+	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
+	if (!cmd)
+		return -ENOMEM;
+
+	cmd->id = CMD_SET_CTRL_MODE;
+	cmd->len = CMD_HEADER_LEN + sizeof(struct kvaser_cmd_ctrl_mode);
+	cmd->u.ctrl_mode.tid = 0xff;
+	cmd->u.ctrl_mode.channel = priv->channel;
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
+		cmd->u.ctrl_mode.ctrl_mode = KVASER_CTRL_MODE_SILENT;
+	else
+		cmd->u.ctrl_mode.ctrl_mode = KVASER_CTRL_MODE_NORMAL;
+
+	rc = kvaser_usb_send_cmd(priv->dev, cmd, cmd->len);
+
+	kfree(cmd);
+	return rc;
+}
+
+static int kvaser_usb_leaf_start_chip(struct kvaser_usb_net_priv *priv)
+{
+	int err;
+
+	init_completion(&priv->start_comp);
+
+	err = kvaser_usb_leaf_send_simple_cmd(priv->dev, CMD_START_CHIP,
+					      priv->channel);
+	if (err)
+		return err;
+
+	if (!wait_for_completion_timeout(&priv->start_comp,
+					 msecs_to_jiffies(KVASER_USB_TIMEOUT)))
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+static int kvaser_usb_leaf_stop_chip(struct kvaser_usb_net_priv *priv)
+{
+	int err;
+
+	init_completion(&priv->stop_comp);
+
+	err = kvaser_usb_leaf_send_simple_cmd(priv->dev, CMD_STOP_CHIP,
+					      priv->channel);
+	if (err)
+		return err;
+
+	if (!wait_for_completion_timeout(&priv->stop_comp,
+					 msecs_to_jiffies(KVASER_USB_TIMEOUT)))
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+static int kvaser_usb_leaf_reset_chip(struct kvaser_usb *dev, int channel)
+{
+	return kvaser_usb_leaf_send_simple_cmd(dev, CMD_RESET_CHIP, channel);
+}
+
+static int kvaser_usb_leaf_flush_queue(struct kvaser_usb_net_priv *priv)
+{
+	struct kvaser_cmd *cmd;
+	int rc;
+
+	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
+	if (!cmd)
+		return -ENOMEM;
+
+	cmd->id = CMD_FLUSH_QUEUE;
+	cmd->len = CMD_HEADER_LEN + sizeof(struct kvaser_cmd_flush_queue);
+	cmd->u.flush_queue.channel = priv->channel;
+	cmd->u.flush_queue.flags = 0x00;
+
+	rc = kvaser_usb_send_cmd(priv->dev, cmd, cmd->len);
+
+	kfree(cmd);
+	return rc;
+}
+
+static int kvaser_usb_leaf_init_card(struct kvaser_usb *dev)
+{
+	struct kvaser_usb_dev_card_data *card_data = &dev->card_data;
+
+	dev->cfg = &kvaser_usb_leaf_dev_cfg;
+	card_data->ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
+
+	return 0;
+}
+
+static const struct can_bittiming_const kvaser_usb_leaf_bittiming_const = {
+	.name = "kvaser_usb",
+	.tseg1_min = KVASER_USB_TSEG1_MIN,
+	.tseg1_max = KVASER_USB_TSEG1_MAX,
+	.tseg2_min = KVASER_USB_TSEG2_MIN,
+	.tseg2_max = KVASER_USB_TSEG2_MAX,
+	.sjw_max = KVASER_USB_SJW_MAX,
+	.brp_min = KVASER_USB_BRP_MIN,
+	.brp_max = KVASER_USB_BRP_MAX,
+	.brp_inc = KVASER_USB_BRP_INC,
+};
+
+static int kvaser_usb_leaf_set_bittiming(struct net_device *netdev)
+{
+	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
+	struct can_bittiming *bt = &priv->can.bittiming;
+	struct kvaser_usb *dev = priv->dev;
+	struct kvaser_cmd *cmd;
+	int rc;
+
+	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
+	if (!cmd)
+		return -ENOMEM;
+
+	cmd->id = CMD_SET_BUS_PARAMS;
+	cmd->len = CMD_HEADER_LEN + sizeof(struct kvaser_cmd_busparams);
+	cmd->u.busparams.channel = priv->channel;
+	cmd->u.busparams.tid = 0xff;
+	cmd->u.busparams.bitrate = cpu_to_le32(bt->bitrate);
+	cmd->u.busparams.sjw = bt->sjw;
+	cmd->u.busparams.tseg1 = bt->prop_seg + bt->phase_seg1;
+	cmd->u.busparams.tseg2 = bt->phase_seg2;
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
+		cmd->u.busparams.no_samp = 3;
+	else
+		cmd->u.busparams.no_samp = 1;
+
+	rc = kvaser_usb_send_cmd(dev, cmd, cmd->len);
+
+	kfree(cmd);
+	return rc;
+}
+
+static int kvaser_usb_leaf_set_mode(struct net_device *netdev,
+				    enum can_mode mode)
+{
+	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
+	int err;
+
+	switch (mode) {
+	case CAN_MODE_START:
+		err = kvaser_usb_leaf_simple_cmd_async(priv, CMD_START_CHIP);
+		if (err)
+			return err;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static int kvaser_usb_leaf_get_berr_counter(const struct net_device *netdev,
+					    struct can_berr_counter *bec)
+{
+	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
+
+	*bec = priv->bec;
+
+	return 0;
+}
+
+static int kvaser_usb_leaf_setup_endpoints(struct kvaser_usb *dev)
+{
+	const struct usb_host_interface *iface_desc;
+	struct usb_endpoint_descriptor *endpoint;
+	int i;
+
+	iface_desc = &dev->intf->altsetting[0];
+
+	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
+		endpoint = &iface_desc->endpoint[i].desc;
+
+		if (!dev->bulk_in && usb_endpoint_is_bulk_in(endpoint))
+			dev->bulk_in = endpoint;
+
+		if (!dev->bulk_out && usb_endpoint_is_bulk_out(endpoint))
+			dev->bulk_out = endpoint;
+
+		/* use first bulk endpoint for in and out */
+		if (dev->bulk_in && dev->bulk_out)
+			return 0;
+	}
+
+	return -ENODEV;
+}
+
+const struct kvaser_usb_dev_ops kvaser_usb_leaf_dev_ops = {
+	.dev_set_mode = kvaser_usb_leaf_set_mode,
+	.dev_set_bittiming = kvaser_usb_leaf_set_bittiming,
+	.dev_get_berr_counter = kvaser_usb_leaf_get_berr_counter,
+	.dev_setup_endpoints = kvaser_usb_leaf_setup_endpoints,
+	.dev_init_card = kvaser_usb_leaf_init_card,
+	.dev_get_software_info = kvaser_usb_leaf_get_software_info,
+	.dev_get_card_info = kvaser_usb_leaf_get_card_info,
+	.dev_set_opt_mode = kvaser_usb_leaf_set_opt_mode,
+	.dev_start_chip = kvaser_usb_leaf_start_chip,
+	.dev_stop_chip = kvaser_usb_leaf_stop_chip,
+	.dev_reset_chip = kvaser_usb_leaf_reset_chip,
+	.dev_flush_queue = kvaser_usb_leaf_flush_queue,
+	.dev_read_bulk_callback = kvaser_usb_leaf_read_bulk_callback,
+	.dev_frame_to_cmd = kvaser_usb_leaf_frame_to_cmd,
+};
+
+static const struct kvaser_usb_dev_cfg kvaser_usb_leaf_dev_cfg = {
+	.clock = {
+		.freq = CAN_USB_CLOCK,
+	},
+	.timestamp_freq = 1,
+	.bittiming_const = &kvaser_usb_leaf_bittiming_const,
+};