root/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c
// SPDX-License-Identifier: GPL-2.0
/* Parts of this driver are based on the following:
 *  - Kvaser linux mhydra driver (version 5.24)
 *  - CAN driver for esd CAN-USB/2
 *
 * Copyright (C) 2018 KVASER AB, Sweden. All rights reserved.
 * Copyright (C) 2010 Matthias Fuchs <matthias.fuchs@esd.eu>, esd gmbh
 *
 * Known issues:
 *  - Transition from CAN_STATE_ERROR_WARNING to CAN_STATE_ERROR_ACTIVE is only
 *    reported after a call to do_get_berr_counter(), since firmware does not
 *    distinguish between ERROR_WARNING and ERROR_ACTIVE.
 */

#include <linux/bitfield.h>
#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/units.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 declarations */
static const struct kvaser_usb_dev_cfg kvaser_usb_hydra_dev_cfg_kcan;
static const struct kvaser_usb_dev_cfg kvaser_usb_hydra_dev_cfg_flexc;
static const struct kvaser_usb_dev_cfg kvaser_usb_hydra_dev_cfg_rt;

#define KVASER_USB_HYDRA_BULK_EP_IN_ADDR        0x82
#define KVASER_USB_HYDRA_BULK_EP_OUT_ADDR       0x02

#define KVASER_USB_HYDRA_MAX_TRANSID            0xff
#define KVASER_USB_HYDRA_MIN_TRANSID            0x01

/* Minihydra command IDs */
#define CMD_SET_BUSPARAMS_REQ                   16
#define CMD_GET_BUSPARAMS_REQ                   17
#define CMD_GET_BUSPARAMS_RESP                  18
#define CMD_GET_CHIP_STATE_REQ                  19
#define CMD_CHIP_STATE_EVENT                    20
#define CMD_SET_DRIVERMODE_REQ                  21
#define CMD_START_CHIP_REQ                      26
#define CMD_START_CHIP_RESP                     27
#define CMD_STOP_CHIP_REQ                       28
#define CMD_STOP_CHIP_RESP                      29
#define CMD_TX_CAN_MESSAGE                      33
#define CMD_GET_CARD_INFO_REQ                   34
#define CMD_GET_CARD_INFO_RESP                  35
#define CMD_GET_SOFTWARE_INFO_REQ               38
#define CMD_GET_SOFTWARE_INFO_RESP              39
#define CMD_ERROR_EVENT                         45
#define CMD_FLUSH_QUEUE                         48
#define CMD_TX_ACKNOWLEDGE                      50
#define CMD_FLUSH_QUEUE_RESP                    66
#define CMD_SET_BUSPARAMS_FD_REQ                69
#define CMD_SET_BUSPARAMS_FD_RESP               70
#define CMD_SET_BUSPARAMS_RESP                  85
#define CMD_GET_CAPABILITIES_REQ                95
#define CMD_GET_CAPABILITIES_RESP               96
#define CMD_LED_ACTION_REQ                      101
#define CMD_LED_ACTION_RESP                     102
#define CMD_RX_MESSAGE                          106
#define CMD_MAP_CHANNEL_REQ                     200
#define CMD_MAP_CHANNEL_RESP                    201
#define CMD_GET_SOFTWARE_DETAILS_REQ            202
#define CMD_GET_SOFTWARE_DETAILS_RESP           203
#define CMD_EXTENDED                            255

/* Minihydra extended command IDs */
#define CMD_TX_CAN_MESSAGE_FD                   224
#define CMD_TX_ACKNOWLEDGE_FD                   225
#define CMD_RX_MESSAGE_FD                       226

/* Hydra commands are handled by different threads in firmware.
 * The threads are denoted hydra entity (HE). Each HE got a unique 6-bit
 * address. The address is used in hydra commands to get/set source and
 * destination HE. There are two predefined HE addresses, the remaining
 * addresses are different between devices and firmware versions. Hence, we need
 * to enumerate the addresses (see kvaser_usb_hydra_map_channel()).
 */

/* Well-known HE addresses */
#define KVASER_USB_HYDRA_HE_ADDRESS_ROUTER      0x00
#define KVASER_USB_HYDRA_HE_ADDRESS_ILLEGAL     0x3e

#define KVASER_USB_HYDRA_TRANSID_CANHE          0x40
#define KVASER_USB_HYDRA_TRANSID_SYSDBG         0x61

struct kvaser_cmd_map_ch_req {
        char name[16];
        u8 channel;
        u8 reserved[11];
} __packed;

struct kvaser_cmd_map_ch_res {
        u8 he_addr;
        u8 channel;
        u8 reserved[26];
} __packed;

struct kvaser_cmd_card_info {
        __le32 serial_number;
        __le32 clock_res;
        __le32 mfg_date;
        __le32 ean[2];
        u8 hw_revision;
        u8 usb_mode;
        u8 hw_type;
        u8 reserved0;
        u8 nchannels;
        u8 reserved1[3];
} __packed;

struct kvaser_cmd_sw_info {
        u8 reserved0[8];
        __le16 max_outstanding_tx;
        u8 reserved1[18];
} __packed;

struct kvaser_cmd_sw_detail_req {
        u8 use_ext_cmd;
        u8 reserved[27];
} __packed;

/* Software detail flags */
#define KVASER_USB_HYDRA_SW_FLAG_FW_BETA        BIT(2)
#define KVASER_USB_HYDRA_SW_FLAG_FW_BAD         BIT(4)
#define KVASER_USB_HYDRA_SW_FLAG_FREQ_80M       BIT(5)
#define KVASER_USB_HYDRA_SW_FLAG_EXT_CMD        BIT(9)
#define KVASER_USB_HYDRA_SW_FLAG_CANFD          BIT(10)
#define KVASER_USB_HYDRA_SW_FLAG_NONISO         BIT(11)
#define KVASER_USB_HYDRA_SW_FLAG_EXT_CAP        BIT(12)
#define KVASER_USB_HYDRA_SW_FLAG_CAN_FREQ_80M   BIT(13)
struct kvaser_cmd_sw_detail_res {
        __le32 sw_flags;
        __le32 sw_version;
        __le32 sw_name;
        __le32 ean[2];
        __le32 max_bitrate;
        u8 reserved[4];
} __packed;

/* Sub commands for cap_req and cap_res */
#define KVASER_USB_HYDRA_CAP_CMD_LISTEN_MODE    0x02
#define KVASER_USB_HYDRA_CAP_CMD_ERR_REPORT     0x05
#define KVASER_USB_HYDRA_CAP_CMD_ONE_SHOT       0x06
struct kvaser_cmd_cap_req {
        __le16 cap_cmd;
        u8 reserved[26];
} __packed;

/* Status codes for cap_res */
#define KVASER_USB_HYDRA_CAP_STAT_OK            0x00
#define KVASER_USB_HYDRA_CAP_STAT_NOT_IMPL      0x01
#define KVASER_USB_HYDRA_CAP_STAT_UNAVAIL       0x02
struct kvaser_cmd_cap_res {
        __le16 cap_cmd;
        __le16 status;
        __le32 mask;
        __le32 value;
        u8 reserved[16];
} __packed;

/* CMD_ERROR_EVENT error codes */
#define KVASER_USB_HYDRA_ERROR_EVENT_CAN        0x01
#define KVASER_USB_HYDRA_ERROR_EVENT_PARAM      0x09
struct kvaser_cmd_error_event {
        __le16 timestamp[3];
        u8 reserved;
        u8 error_code;
        __le16 info1;
        __le16 info2;
} __packed;

/* Chip state status flags. Used for chip_state_event and err_frame_data. */
#define KVASER_USB_HYDRA_BUS_ERR_ACT            0x00
#define KVASER_USB_HYDRA_BUS_ERR_PASS           BIT(5)
#define KVASER_USB_HYDRA_BUS_BUS_OFF            BIT(6)
struct kvaser_cmd_chip_state_event {
        __le16 timestamp[3];
        u8 tx_err_counter;
        u8 rx_err_counter;
        u8 bus_status;
        u8 reserved[19];
} __packed;

/* Busparam modes */
#define KVASER_USB_HYDRA_BUS_MODE_CAN           0x00
#define KVASER_USB_HYDRA_BUS_MODE_CANFD_ISO     0x01
#define KVASER_USB_HYDRA_BUS_MODE_NONISO        0x02
struct kvaser_cmd_set_busparams {
        struct kvaser_usb_busparams busparams_nominal;
        u8 reserved0[4];
        struct kvaser_usb_busparams busparams_data;
        u8 canfd_mode;
        u8 reserved1[7];
} __packed;

/* Busparam type */
#define KVASER_USB_HYDRA_BUSPARAM_TYPE_CAN      0x00
#define KVASER_USB_HYDRA_BUSPARAM_TYPE_CANFD    0x01
struct kvaser_cmd_get_busparams_req {
        u8 type;
        u8 reserved[27];
} __packed;

struct kvaser_cmd_get_busparams_res {
        struct kvaser_usb_busparams busparams;
        u8 reserved[20];
} __packed;

/* The device has two LEDs per CAN channel
 * The LSB of action field controls the state:
 *   0 = ON
 *   1 = OFF
 * The remaining bits of action field is the LED index
 */
#define KVASER_USB_HYDRA_LED_IDX_MASK GENMASK(31, 1)
#define KVASER_USB_HYDRA_LED_YELLOW_CH0_IDX 3
#define KVASER_USB_HYDRA_LEDS_PER_CHANNEL 2
struct kvaser_cmd_led_action_req {
        u8 action;
        u8 padding;
        __le16 duration_ms;
        u8 reserved[24];
} __packed;

/* Ctrl modes */
#define KVASER_USB_HYDRA_CTRLMODE_NORMAL        0x01
#define KVASER_USB_HYDRA_CTRLMODE_LISTEN        0x02
struct kvaser_cmd_set_ctrlmode {
        u8 mode;
        u8 reserved[27];
} __packed;

struct kvaser_err_frame_data {
        u8 bus_status;
        u8 reserved0;
        u8 tx_err_counter;
        u8 rx_err_counter;
        u8 reserved1[4];
} __packed;

struct kvaser_cmd_rx_can {
        u8 cmd_len;
        u8 cmd_no;
        u8 channel;
        u8 flags;
        __le16 timestamp[3];
        u8 dlc;
        u8 padding;
        __le32 id;
        union {
                u8 data[8];
                struct kvaser_err_frame_data err_frame_data;
        };
} __packed;

/* Extended CAN ID flag. Used in rx_can and tx_can */
#define KVASER_USB_HYDRA_EXTENDED_FRAME_ID      BIT(31)
struct kvaser_cmd_tx_can {
        __le32 id;
        u8 data[8];
        u8 dlc;
        u8 flags;
        __le16 transid;
        u8 channel;
        u8 reserved[11];
} __packed;

struct kvaser_cmd_tx_ack {
        __le32 id;
        u8 data[8];
        u8 dlc;
        u8 flags;
        __le16 timestamp[3];
        u8 reserved0[8];
} __packed;

struct kvaser_cmd_header {
        u8 cmd_no;
        /* The destination HE address is stored in 0..5 of he_addr.
         * The upper part of source HE address is stored in 6..7 of he_addr, and
         * the lower part is stored in 12..15 of transid.
         */
        u8 he_addr;
        __le16 transid;
} __packed;

struct kvaser_cmd {
        struct kvaser_cmd_header header;
        union {
                struct kvaser_cmd_map_ch_req map_ch_req;
                struct kvaser_cmd_map_ch_res map_ch_res;

                struct kvaser_cmd_card_info card_info;
                struct kvaser_cmd_sw_info sw_info;
                struct kvaser_cmd_sw_detail_req sw_detail_req;
                struct kvaser_cmd_sw_detail_res sw_detail_res;

                struct kvaser_cmd_cap_req cap_req;
                struct kvaser_cmd_cap_res cap_res;

                struct kvaser_cmd_error_event error_event;

                struct kvaser_cmd_set_busparams set_busparams_req;
                struct kvaser_cmd_get_busparams_req get_busparams_req;
                struct kvaser_cmd_get_busparams_res get_busparams_res;

                struct kvaser_cmd_led_action_req led_action_req;

                struct kvaser_cmd_chip_state_event chip_state_event;

                struct kvaser_cmd_set_ctrlmode set_ctrlmode;

                struct kvaser_cmd_rx_can rx_can;
                struct kvaser_cmd_tx_can tx_can;
                struct kvaser_cmd_tx_ack tx_ack;
        } __packed;
} __packed;

/* CAN frame flags. Used in rx_can, ext_rx_can, tx_can and ext_tx_can */
#define KVASER_USB_HYDRA_CF_FLAG_ERROR_FRAME    BIT(0)
#define KVASER_USB_HYDRA_CF_FLAG_OVERRUN        BIT(1)
#define KVASER_USB_HYDRA_CF_FLAG_REMOTE_FRAME   BIT(4)
#define KVASER_USB_HYDRA_CF_FLAG_EXTENDED_ID    BIT(5)
#define KVASER_USB_HYDRA_CF_FLAG_TX_ACK         BIT(6)
/* CAN frame flags. Used in ext_rx_can and ext_tx_can */
#define KVASER_USB_HYDRA_CF_FLAG_OSM_NACK       BIT(12)
#define KVASER_USB_HYDRA_CF_FLAG_ABL            BIT(13)
#define KVASER_USB_HYDRA_CF_FLAG_FDF            BIT(16)
#define KVASER_USB_HYDRA_CF_FLAG_BRS            BIT(17)
#define KVASER_USB_HYDRA_CF_FLAG_ESI            BIT(18)

/* KCAN packet header macros. Used in ext_rx_can and ext_tx_can */
#define KVASER_USB_KCAN_DATA_DLC_BITS           4
#define KVASER_USB_KCAN_DATA_DLC_SHIFT          8
#define KVASER_USB_KCAN_DATA_DLC_MASK \
                                GENMASK(KVASER_USB_KCAN_DATA_DLC_BITS - 1 + \
                                KVASER_USB_KCAN_DATA_DLC_SHIFT, \
                                KVASER_USB_KCAN_DATA_DLC_SHIFT)

#define KVASER_USB_KCAN_DATA_BRS                BIT(14)
#define KVASER_USB_KCAN_DATA_FDF                BIT(15)
#define KVASER_USB_KCAN_DATA_OSM                BIT(16)
#define KVASER_USB_KCAN_DATA_AREQ               BIT(31)
#define KVASER_USB_KCAN_DATA_SRR                BIT(31)
#define KVASER_USB_KCAN_DATA_RTR                BIT(29)
#define KVASER_USB_KCAN_DATA_IDE                BIT(30)
struct kvaser_cmd_ext_rx_can {
        __le32 flags;
        __le32 id;
        __le32 kcan_id;
        __le32 kcan_header;
        __le64 timestamp;
        union {
                u8 kcan_payload[64];
                struct kvaser_err_frame_data err_frame_data;
        };
} __packed;

struct kvaser_cmd_ext_tx_can {
        __le32 flags;
        __le32 id;
        __le32 kcan_id;
        __le32 kcan_header;
        u8 databytes;
        u8 dlc;
        u8 reserved[6];
        u8 kcan_payload[64];
} __packed;

struct kvaser_cmd_ext_tx_ack {
        __le32 flags;
        u8 reserved0[4];
        __le64 timestamp;
        u8 reserved1[8];
} __packed;

/* struct for extended commands (CMD_EXTENDED) */
struct kvaser_cmd_ext {
        struct kvaser_cmd_header header;
        __le16 len;
        u8 cmd_no_ext;
        u8 reserved;

        union {
                struct kvaser_cmd_ext_rx_can rx_can;
                struct kvaser_cmd_ext_tx_can tx_can;
                struct kvaser_cmd_ext_tx_ack tx_ack;
        } __packed;
} __packed;

struct kvaser_usb_net_hydra_priv {
        int pending_get_busparams_type;
};

static const struct can_bittiming_const kvaser_usb_hydra_kcan_bittiming_c = {
        .name = "kvaser_usb_kcan",
        .tseg1_min = 1,
        .tseg1_max = 255,
        .tseg2_min = 1,
        .tseg2_max = 32,
        .sjw_max = 16,
        .brp_min = 1,
        .brp_max = 8192,
        .brp_inc = 1,
};

const struct can_bittiming_const kvaser_usb_flexc_bittiming_const = {
        .name = "kvaser_usb_flex",
        .tseg1_min = 4,
        .tseg1_max = 16,
        .tseg2_min = 2,
        .tseg2_max = 8,
        .sjw_max = 4,
        .brp_min = 1,
        .brp_max = 256,
        .brp_inc = 1,
};

static const struct can_bittiming_const kvaser_usb_hydra_rt_bittiming_c = {
        .name = "kvaser_usb_rt",
        .tseg1_min = 2,
        .tseg1_max = 96,
        .tseg2_min = 2,
        .tseg2_max = 32,
        .sjw_max = 32,
        .brp_min = 1,
        .brp_max = 1024,
        .brp_inc = 1,
};

static const struct can_bittiming_const kvaser_usb_hydra_rtd_bittiming_c = {
        .name = "kvaser_usb_rt",
        .tseg1_min = 2,
        .tseg1_max = 39,
        .tseg2_min = 2,
        .tseg2_max = 8,
        .sjw_max = 8,
        .brp_min = 1,
        .brp_max = 1024,
        .brp_inc = 1,
};

#define KVASER_USB_HYDRA_TRANSID_BITS           12
#define KVASER_USB_HYDRA_TRANSID_MASK \
                                GENMASK(KVASER_USB_HYDRA_TRANSID_BITS - 1, 0)
#define KVASER_USB_HYDRA_HE_ADDR_SRC_MASK       GENMASK(7, 6)
#define KVASER_USB_HYDRA_HE_ADDR_DEST_MASK      GENMASK(5, 0)
#define KVASER_USB_HYDRA_HE_ADDR_SRC_BITS       2
static inline u16 kvaser_usb_hydra_get_cmd_transid(const struct kvaser_cmd *cmd)
{
        return le16_to_cpu(cmd->header.transid) & KVASER_USB_HYDRA_TRANSID_MASK;
}

static inline void kvaser_usb_hydra_set_cmd_transid(struct kvaser_cmd *cmd,
                                                    u16 transid)
{
        cmd->header.transid =
                        cpu_to_le16(transid & KVASER_USB_HYDRA_TRANSID_MASK);
}

static inline u8 kvaser_usb_hydra_get_cmd_src_he(const struct kvaser_cmd *cmd)
{
        return (cmd->header.he_addr & KVASER_USB_HYDRA_HE_ADDR_SRC_MASK) >>
                KVASER_USB_HYDRA_HE_ADDR_SRC_BITS |
                le16_to_cpu(cmd->header.transid) >>
                KVASER_USB_HYDRA_TRANSID_BITS;
}

static inline void kvaser_usb_hydra_set_cmd_dest_he(struct kvaser_cmd *cmd,
                                                    u8 dest_he)
{
        cmd->header.he_addr =
                (cmd->header.he_addr & KVASER_USB_HYDRA_HE_ADDR_SRC_MASK) |
                (dest_he & KVASER_USB_HYDRA_HE_ADDR_DEST_MASK);
}

static u8 kvaser_usb_hydra_channel_from_cmd(const struct kvaser_usb *dev,
                                            const struct kvaser_cmd *cmd)
{
        int i;
        u8 channel = 0xff;
        u8 src_he = kvaser_usb_hydra_get_cmd_src_he(cmd);

        for (i = 0; i < KVASER_USB_MAX_NET_DEVICES; i++) {
                if (dev->card_data.hydra.channel_to_he[i] == src_he) {
                        channel = i;
                        break;
                }
        }

        return channel;
}

static u16 kvaser_usb_hydra_get_next_transid(struct kvaser_usb *dev)
{
        unsigned long flags;
        u16 transid;
        struct kvaser_usb_dev_card_data_hydra *card_data =
                                                        &dev->card_data.hydra;

        spin_lock_irqsave(&card_data->transid_lock, flags);
        transid = card_data->transid;
        if (transid >= KVASER_USB_HYDRA_MAX_TRANSID)
                transid = KVASER_USB_HYDRA_MIN_TRANSID;
        else
                transid++;
        card_data->transid = transid;
        spin_unlock_irqrestore(&card_data->transid_lock, flags);

        return transid;
}

static size_t kvaser_usb_hydra_cmd_size(struct kvaser_cmd *cmd)
{
        size_t ret;

        if (cmd->header.cmd_no == CMD_EXTENDED)
                ret = le16_to_cpu(((struct kvaser_cmd_ext *)cmd)->len);
        else
                ret = sizeof(struct kvaser_cmd);

        return ret;
}

static struct kvaser_usb_net_priv *
kvaser_usb_hydra_net_priv_from_cmd(const struct kvaser_usb *dev,
                                   const struct kvaser_cmd *cmd)
{
        struct kvaser_usb_net_priv *priv = NULL;
        u8 channel = kvaser_usb_hydra_channel_from_cmd(dev, cmd);

        if (channel >= dev->nchannels)
                dev_err(&dev->intf->dev,
                        "Invalid channel number (%d)\n", channel);
        else
                priv = dev->nets[channel];

        return priv;
}

static ktime_t kvaser_usb_hydra_ktime_from_cmd(const struct kvaser_usb_dev_cfg *cfg,
                                               const struct kvaser_cmd *cmd)
{
        ktime_t hwtstamp = 0;

        if (cmd->header.cmd_no == CMD_EXTENDED) {
                struct kvaser_cmd_ext *cmd_ext = (struct kvaser_cmd_ext *)cmd;

                if (cmd_ext->cmd_no_ext == CMD_RX_MESSAGE_FD)
                        hwtstamp = kvaser_usb_timestamp64_to_ktime(cfg, cmd_ext->rx_can.timestamp);
                else if (cmd_ext->cmd_no_ext == CMD_TX_ACKNOWLEDGE_FD)
                        hwtstamp = kvaser_usb_timestamp64_to_ktime(cfg, cmd_ext->tx_ack.timestamp);
        } else if (cmd->header.cmd_no == CMD_RX_MESSAGE) {
                hwtstamp = kvaser_usb_timestamp48_to_ktime(cfg, cmd->rx_can.timestamp);
        } else if (cmd->header.cmd_no == CMD_TX_ACKNOWLEDGE) {
                hwtstamp = kvaser_usb_timestamp48_to_ktime(cfg, cmd->tx_ack.timestamp);
        }

        return hwtstamp;
}

static int kvaser_usb_hydra_send_simple_cmd(struct kvaser_usb *dev,
                                            u8 cmd_no, int channel)
{
        struct kvaser_cmd *cmd;
        size_t cmd_len;
        int err;

        cmd = kzalloc_obj(*cmd);
        if (!cmd)
                return -ENOMEM;

        cmd->header.cmd_no = cmd_no;
        cmd_len = kvaser_usb_hydra_cmd_size(cmd);
        if (channel < 0) {
                kvaser_usb_hydra_set_cmd_dest_he
                                (cmd, KVASER_USB_HYDRA_HE_ADDRESS_ILLEGAL);
        } else {
                if (channel >= KVASER_USB_MAX_NET_DEVICES) {
                        dev_err(&dev->intf->dev, "channel (%d) out of range.\n",
                                channel);
                        err = -EINVAL;
                        goto end;
                }
                kvaser_usb_hydra_set_cmd_dest_he
                        (cmd, dev->card_data.hydra.channel_to_he[channel]);
        }
        kvaser_usb_hydra_set_cmd_transid
                                (cmd, kvaser_usb_hydra_get_next_transid(dev));

        err = kvaser_usb_send_cmd(dev, cmd, cmd_len);
        if (err)
                goto end;

end:
        kfree(cmd);

        return err;
}

static int
kvaser_usb_hydra_send_simple_cmd_async(struct kvaser_usb_net_priv *priv,
                                       u8 cmd_no)
{
        struct kvaser_cmd *cmd;
        struct kvaser_usb *dev = priv->dev;
        size_t cmd_len;
        int err;

        cmd = kzalloc_obj(*cmd, GFP_ATOMIC);
        if (!cmd)
                return -ENOMEM;

        cmd->header.cmd_no = cmd_no;
        cmd_len = kvaser_usb_hydra_cmd_size(cmd);

        kvaser_usb_hydra_set_cmd_dest_he
                (cmd, dev->card_data.hydra.channel_to_he[priv->channel]);
        kvaser_usb_hydra_set_cmd_transid
                                (cmd, kvaser_usb_hydra_get_next_transid(dev));

        err = kvaser_usb_send_cmd_async(priv, cmd, cmd_len);
        if (err)
                kfree(cmd);

        return err;
}

/* This function is used for synchronously waiting on hydra control commands.
 * Note: Compared to kvaser_usb_hydra_read_bulk_callback(), we never need to
 *       handle partial hydra commands. Since hydra control commands are always
 *       non-extended commands.
 */
static int kvaser_usb_hydra_wait_cmd(const struct kvaser_usb *dev, u8 cmd_no,
                                     struct kvaser_cmd *cmd)
{
        void *buf;
        int err;
        unsigned long timeout = jiffies + msecs_to_jiffies(KVASER_USB_TIMEOUT);

        if (cmd->header.cmd_no == CMD_EXTENDED) {
                dev_err(&dev->intf->dev, "Wait for CMD_EXTENDED not allowed\n");
                return -EINVAL;
        }

        buf = kzalloc(KVASER_USB_RX_BUFFER_SIZE, GFP_KERNEL);
        if (!buf)
                return -ENOMEM;

        do {
                int actual_len = 0;
                int pos = 0;

                err = kvaser_usb_recv_cmd(dev, buf, KVASER_USB_RX_BUFFER_SIZE,
                                          &actual_len);
                if (err < 0)
                        goto end;

                while (pos < actual_len) {
                        struct kvaser_cmd *tmp_cmd;
                        size_t cmd_len;

                        tmp_cmd = buf + pos;
                        cmd_len = kvaser_usb_hydra_cmd_size(tmp_cmd);
                        if (pos + cmd_len > actual_len) {
                                dev_err_ratelimited(&dev->intf->dev,
                                                    "Format error\n");
                                break;
                        }

                        if (tmp_cmd->header.cmd_no == cmd_no) {
                                memcpy(cmd, tmp_cmd, cmd_len);
                                goto end;
                        }
                        pos += cmd_len;
                }
        } while (time_before(jiffies, timeout));

        err = -EINVAL;

end:
        kfree(buf);

        return err;
}

static int kvaser_usb_hydra_map_channel_resp(struct kvaser_usb *dev,
                                             const struct kvaser_cmd *cmd)
{
        u8 he, channel;
        u16 transid = kvaser_usb_hydra_get_cmd_transid(cmd);
        struct kvaser_usb_dev_card_data_hydra *card_data =
                                                        &dev->card_data.hydra;

        if (transid > 0x007f || transid < 0x0040) {
                dev_err(&dev->intf->dev,
                        "CMD_MAP_CHANNEL_RESP, invalid transid: 0x%x\n",
                        transid);
                return -EINVAL;
        }

        switch (transid) {
        case KVASER_USB_HYDRA_TRANSID_CANHE:
        case KVASER_USB_HYDRA_TRANSID_CANHE + 1:
        case KVASER_USB_HYDRA_TRANSID_CANHE + 2:
        case KVASER_USB_HYDRA_TRANSID_CANHE + 3:
        case KVASER_USB_HYDRA_TRANSID_CANHE + 4:
                channel = transid & 0x000f;
                he = cmd->map_ch_res.he_addr;
                card_data->channel_to_he[channel] = he;
                break;
        case KVASER_USB_HYDRA_TRANSID_SYSDBG:
                card_data->sysdbg_he = cmd->map_ch_res.he_addr;
                break;
        default:
                dev_warn(&dev->intf->dev,
                         "Unknown CMD_MAP_CHANNEL_RESP transid=0x%x\n",
                         transid);
                break;
        }

        return 0;
}

static int kvaser_usb_hydra_map_channel(struct kvaser_usb *dev, u16 transid,
                                        u8 channel, const char *name)
{
        struct kvaser_cmd *cmd;
        int err;

        cmd = kzalloc_obj(*cmd);
        if (!cmd)
                return -ENOMEM;

        strcpy(cmd->map_ch_req.name, name);
        cmd->header.cmd_no = CMD_MAP_CHANNEL_REQ;
        kvaser_usb_hydra_set_cmd_dest_he
                                (cmd, KVASER_USB_HYDRA_HE_ADDRESS_ROUTER);
        cmd->map_ch_req.channel = channel;

        kvaser_usb_hydra_set_cmd_transid(cmd, transid);

        err = kvaser_usb_send_cmd(dev, cmd, kvaser_usb_hydra_cmd_size(cmd));
        if (err)
                goto end;

        err = kvaser_usb_hydra_wait_cmd(dev, CMD_MAP_CHANNEL_RESP, cmd);
        if (err)
                goto end;

        err = kvaser_usb_hydra_map_channel_resp(dev, cmd);
        if (err)
                goto end;

end:
        kfree(cmd);

        return err;
}

static int kvaser_usb_hydra_get_single_capability(struct kvaser_usb *dev,
                                                  u16 cap_cmd_req, u16 *status)
{
        struct kvaser_usb_dev_card_data *card_data = &dev->card_data;
        struct kvaser_cmd *cmd;
        size_t cmd_len;
        u32 value = 0;
        u32 mask = 0;
        u16 cap_cmd_res;
        int err;
        int i;

        cmd = kzalloc_obj(*cmd);
        if (!cmd)
                return -ENOMEM;

        cmd->header.cmd_no = CMD_GET_CAPABILITIES_REQ;
        cmd_len = kvaser_usb_hydra_cmd_size(cmd);
        cmd->cap_req.cap_cmd = cpu_to_le16(cap_cmd_req);

        kvaser_usb_hydra_set_cmd_dest_he(cmd, card_data->hydra.sysdbg_he);
        kvaser_usb_hydra_set_cmd_transid
                                (cmd, kvaser_usb_hydra_get_next_transid(dev));

        err = kvaser_usb_send_cmd(dev, cmd, cmd_len);
        if (err)
                goto end;

        err = kvaser_usb_hydra_wait_cmd(dev, CMD_GET_CAPABILITIES_RESP, cmd);
        if (err)
                goto end;

        *status = le16_to_cpu(cmd->cap_res.status);

        if (*status != KVASER_USB_HYDRA_CAP_STAT_OK)
                goto end;

        cap_cmd_res = le16_to_cpu(cmd->cap_res.cap_cmd);
        switch (cap_cmd_res) {
        case KVASER_USB_HYDRA_CAP_CMD_LISTEN_MODE:
        case KVASER_USB_HYDRA_CAP_CMD_ERR_REPORT:
        case KVASER_USB_HYDRA_CAP_CMD_ONE_SHOT:
                value = le32_to_cpu(cmd->cap_res.value);
                mask = le32_to_cpu(cmd->cap_res.mask);
                break;
        default:
                dev_warn(&dev->intf->dev, "Unknown capability command %u\n",
                         cap_cmd_res);
                break;
        }

        for (i = 0; i < dev->nchannels; i++) {
                if (BIT(i) & (value & mask)) {
                        switch (cap_cmd_res) {
                        case KVASER_USB_HYDRA_CAP_CMD_LISTEN_MODE:
                                card_data->ctrlmode_supported |=
                                                CAN_CTRLMODE_LISTENONLY;
                                break;
                        case KVASER_USB_HYDRA_CAP_CMD_ERR_REPORT:
                                card_data->capabilities |=
                                                KVASER_USB_CAP_BERR_CAP;
                                break;
                        case KVASER_USB_HYDRA_CAP_CMD_ONE_SHOT:
                                card_data->ctrlmode_supported |=
                                                CAN_CTRLMODE_ONE_SHOT;
                                break;
                        }
                }
        }

end:
        kfree(cmd);

        return err;
}

static void kvaser_usb_hydra_start_chip_reply(const struct kvaser_usb *dev,
                                              const struct kvaser_cmd *cmd)
{
        struct kvaser_usb_net_priv *priv;

        priv = kvaser_usb_hydra_net_priv_from_cmd(dev, cmd);
        if (!priv)
                return;

        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_hydra_stop_chip_reply(const struct kvaser_usb *dev,
                                             const struct kvaser_cmd *cmd)
{
        struct kvaser_usb_net_priv *priv;

        priv = kvaser_usb_hydra_net_priv_from_cmd(dev, cmd);
        if (!priv)
                return;

        complete(&priv->stop_comp);
}

static void kvaser_usb_hydra_flush_queue_reply(const struct kvaser_usb *dev,
                                               const struct kvaser_cmd *cmd)
{
        struct kvaser_usb_net_priv *priv;

        priv = kvaser_usb_hydra_net_priv_from_cmd(dev, cmd);
        if (!priv)
                return;

        complete(&priv->flush_comp);
}

static void kvaser_usb_hydra_get_busparams_reply(const struct kvaser_usb *dev,
                                                 const struct kvaser_cmd *cmd)
{
        struct kvaser_usb_net_priv *priv;
        struct kvaser_usb_net_hydra_priv *hydra;

        priv = kvaser_usb_hydra_net_priv_from_cmd(dev, cmd);
        if (!priv)
                return;

        hydra = priv->sub_priv;
        if (!hydra)
                return;

        switch (hydra->pending_get_busparams_type) {
        case KVASER_USB_HYDRA_BUSPARAM_TYPE_CAN:
                memcpy(&priv->busparams_nominal, &cmd->get_busparams_res.busparams,
                       sizeof(priv->busparams_nominal));
                break;
        case KVASER_USB_HYDRA_BUSPARAM_TYPE_CANFD:
                memcpy(&priv->busparams_data, &cmd->get_busparams_res.busparams,
                       sizeof(priv->busparams_nominal));
                break;
        default:
                dev_warn(&dev->intf->dev, "Unknown get_busparams_type %d\n",
                         hydra->pending_get_busparams_type);
                break;
        }
        hydra->pending_get_busparams_type = -1;

        complete(&priv->get_busparams_comp);
}

static void
kvaser_usb_hydra_bus_status_to_can_state(const struct kvaser_usb_net_priv *priv,
                                         u8 bus_status,
                                         const struct can_berr_counter *bec,
                                         enum can_state *new_state)
{
        if (bus_status & KVASER_USB_HYDRA_BUS_BUS_OFF) {
                *new_state = CAN_STATE_BUS_OFF;
        } else if (bus_status & KVASER_USB_HYDRA_BUS_ERR_PASS) {
                *new_state = CAN_STATE_ERROR_PASSIVE;
        } else if (bus_status == KVASER_USB_HYDRA_BUS_ERR_ACT) {
                if (bec->txerr >= 128 || bec->rxerr >= 128) {
                        netdev_warn(priv->netdev,
                                    "ERR_ACTIVE but err tx=%u or rx=%u >=128\n",
                                    bec->txerr, bec->rxerr);
                        *new_state = CAN_STATE_ERROR_PASSIVE;
                } else if (bec->txerr >= 96 || bec->rxerr >= 96) {
                        *new_state = CAN_STATE_ERROR_WARNING;
                } else {
                        *new_state = CAN_STATE_ERROR_ACTIVE;
                }
        }
}

static void kvaser_usb_hydra_change_state(struct kvaser_usb_net_priv *priv,
                                          const struct can_berr_counter *bec,
                                          struct can_frame *cf,
                                          enum can_state new_state)
{
        struct net_device *netdev = priv->netdev;
        enum can_state old_state = priv->can.state;
        enum can_state tx_state, rx_state;

        tx_state = (bec->txerr >= bec->rxerr) ?
                                new_state : CAN_STATE_ERROR_ACTIVE;
        rx_state = (bec->txerr <= bec->rxerr) ?
                                new_state : CAN_STATE_ERROR_ACTIVE;
        can_change_state(netdev, cf, tx_state, rx_state);

        if (new_state == CAN_STATE_BUS_OFF && old_state < CAN_STATE_BUS_OFF) {
                if (priv->can.restart_ms == 0)
                        kvaser_usb_hydra_send_simple_cmd_async(priv, CMD_STOP_CHIP_REQ);

                can_bus_off(netdev);
        }

        if (priv->can.restart_ms &&
            old_state >= CAN_STATE_BUS_OFF &&
            new_state < CAN_STATE_BUS_OFF) {
                priv->can.can_stats.restarts++;
                if (cf)
                        cf->can_id |= CAN_ERR_RESTARTED;
        }
        if (cf && new_state != CAN_STATE_BUS_OFF) {
                cf->can_id |= CAN_ERR_CNT;
                cf->data[6] = bec->txerr;
                cf->data[7] = bec->rxerr;
        }
}

static void kvaser_usb_hydra_update_state(struct kvaser_usb_net_priv *priv,
                                          u8 bus_status,
                                          const struct can_berr_counter *bec)
{
        struct net_device *netdev = priv->netdev;
        struct can_frame *cf;
        struct sk_buff *skb;
        enum can_state new_state, old_state;

        old_state = priv->can.state;

        kvaser_usb_hydra_bus_status_to_can_state(priv, bus_status, bec,
                                                 &new_state);

        if (new_state == old_state)
                return;

        /* Ignore state change if previous state was STOPPED and the new state
         * is BUS_OFF. Firmware always report this as BUS_OFF, since firmware
         * does not distinguish between BUS_OFF and STOPPED.
         */
        if (old_state == CAN_STATE_STOPPED && new_state == CAN_STATE_BUS_OFF)
                return;

        skb = alloc_can_err_skb(netdev, &cf);
        kvaser_usb_hydra_change_state(priv, bec, cf, new_state);
        if (skb)
                netif_rx(skb);
        else
                netdev_warn(netdev, "No memory left for err_skb\n");
}

static void kvaser_usb_hydra_state_event(const struct kvaser_usb *dev,
                                         const struct kvaser_cmd *cmd)
{
        struct kvaser_usb_net_priv *priv;
        struct can_berr_counter bec;
        u8 bus_status;

        priv = kvaser_usb_hydra_net_priv_from_cmd(dev, cmd);
        if (!priv)
                return;

        bus_status = cmd->chip_state_event.bus_status;
        bec.txerr = cmd->chip_state_event.tx_err_counter;
        bec.rxerr = cmd->chip_state_event.rx_err_counter;

        kvaser_usb_hydra_update_state(priv, bus_status, &bec);
        priv->bec.txerr = bec.txerr;
        priv->bec.rxerr = bec.rxerr;
}

static void kvaser_usb_hydra_error_event_parameter(const struct kvaser_usb *dev,
                                                   const struct kvaser_cmd *cmd)
{
        /* info1 will contain the offending cmd_no */
        switch (le16_to_cpu(cmd->error_event.info1)) {
        case CMD_START_CHIP_REQ:
                dev_warn(&dev->intf->dev,
                         "CMD_START_CHIP_REQ error in parameter\n");
                break;

        case CMD_STOP_CHIP_REQ:
                dev_warn(&dev->intf->dev,
                         "CMD_STOP_CHIP_REQ error in parameter\n");
                break;

        case CMD_FLUSH_QUEUE:
                dev_warn(&dev->intf->dev,
                         "CMD_FLUSH_QUEUE error in parameter\n");
                break;

        case CMD_SET_BUSPARAMS_REQ:
                dev_warn(&dev->intf->dev,
                         "Set bittiming failed. Error in parameter\n");
                break;

        case CMD_SET_BUSPARAMS_FD_REQ:
                dev_warn(&dev->intf->dev,
                         "Set data bittiming failed. Error in parameter\n");
                break;

        default:
                dev_warn(&dev->intf->dev,
                         "Unhandled parameter error event cmd_no (%u)\n",
                         le16_to_cpu(cmd->error_event.info1));
                break;
        }
}

static void kvaser_usb_hydra_error_event(const struct kvaser_usb *dev,
                                         const struct kvaser_cmd *cmd)
{
        switch (cmd->error_event.error_code) {
        case KVASER_USB_HYDRA_ERROR_EVENT_PARAM:
                kvaser_usb_hydra_error_event_parameter(dev, cmd);
                break;

        case KVASER_USB_HYDRA_ERROR_EVENT_CAN:
                /* Wrong channel mapping?! This should never happen!
                 * info1 will contain the offending cmd_no
                 */
                dev_err(&dev->intf->dev,
                        "Received CAN error event for cmd_no (%u)\n",
                        le16_to_cpu(cmd->error_event.info1));
                break;

        default:
                dev_warn(&dev->intf->dev,
                         "Unhandled error event (%d)\n",
                         cmd->error_event.error_code);
                break;
        }
}

static void
kvaser_usb_hydra_error_frame(struct kvaser_usb_net_priv *priv,
                             const struct kvaser_err_frame_data *err_frame_data,
                             ktime_t hwtstamp)
{
        struct net_device *netdev = priv->netdev;
        struct net_device_stats *stats = &netdev->stats;
        struct can_frame *cf = NULL;
        struct sk_buff *skb = NULL;
        struct can_berr_counter bec;
        enum can_state new_state, old_state;
        u8 bus_status;

        priv->can.can_stats.bus_error++;
        stats->rx_errors++;

        bus_status = err_frame_data->bus_status;
        bec.txerr = err_frame_data->tx_err_counter;
        bec.rxerr = err_frame_data->rx_err_counter;

        old_state = priv->can.state;
        kvaser_usb_hydra_bus_status_to_can_state(priv, bus_status, &bec,
                                                 &new_state);

        if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
                skb = alloc_can_err_skb(netdev, &cf);
        if (new_state != old_state)
                kvaser_usb_hydra_change_state(priv, &bec, cf, new_state);

        if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) {
                if (skb) {
                        struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);

                        shhwtstamps->hwtstamp = hwtstamp;
                        cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_CNT;
                        cf->data[6] = bec.txerr;
                        cf->data[7] = bec.rxerr;
                        netif_rx(skb);
                } else {
                        stats->rx_dropped++;
                        netdev_warn(netdev, "No memory left for err_skb\n");
                }
        }

        priv->bec.txerr = bec.txerr;
        priv->bec.rxerr = bec.rxerr;
}

static void kvaser_usb_hydra_one_shot_fail(struct kvaser_usb_net_priv *priv,
                                           const struct kvaser_cmd_ext *cmd)
{
        struct net_device *netdev = priv->netdev;
        struct net_device_stats *stats = &netdev->stats;
        struct can_frame *cf;
        struct sk_buff *skb;
        u32 flags;

        skb = alloc_can_err_skb(netdev, &cf);
        if (!skb) {
                stats->rx_dropped++;
                netdev_warn(netdev, "No memory left for err_skb\n");
                return;
        }

        cf->can_id |= CAN_ERR_BUSERROR;
        flags = le32_to_cpu(cmd->tx_ack.flags);

        if (flags & KVASER_USB_HYDRA_CF_FLAG_OSM_NACK)
                cf->can_id |= CAN_ERR_ACK;
        if (flags & KVASER_USB_HYDRA_CF_FLAG_ABL) {
                cf->can_id |= CAN_ERR_LOSTARB;
                priv->can.can_stats.arbitration_lost++;
        }

        stats->tx_errors++;
        netif_rx(skb);
}

static void kvaser_usb_hydra_tx_acknowledge(const struct kvaser_usb *dev,
                                            const struct kvaser_cmd *cmd)
{
        struct kvaser_usb_tx_urb_context *context;
        struct kvaser_usb_net_priv *priv;
        unsigned long irq_flags;
        unsigned int len;
        bool one_shot_fail = false;
        bool is_err_frame = false;
        u16 transid = kvaser_usb_hydra_get_cmd_transid(cmd);
        struct sk_buff *skb;

        priv = kvaser_usb_hydra_net_priv_from_cmd(dev, cmd);
        if (!priv)
                return;

        if (!netif_device_present(priv->netdev))
                return;

        if (cmd->header.cmd_no == CMD_EXTENDED) {
                struct kvaser_cmd_ext *cmd_ext = (struct kvaser_cmd_ext *)cmd;
                u32 flags = le32_to_cpu(cmd_ext->tx_ack.flags);

                if (flags & (KVASER_USB_HYDRA_CF_FLAG_OSM_NACK |
                             KVASER_USB_HYDRA_CF_FLAG_ABL)) {
                        kvaser_usb_hydra_one_shot_fail(priv, cmd_ext);
                        one_shot_fail = true;
                }

                is_err_frame = flags & KVASER_USB_HYDRA_CF_FLAG_TX_ACK &&
                               flags & KVASER_USB_HYDRA_CF_FLAG_ERROR_FRAME;
        }

        context = &priv->tx_contexts[transid % dev->max_tx_urbs];

        spin_lock_irqsave(&priv->tx_contexts_lock, irq_flags);

        skb = priv->can.echo_skb[context->echo_index];
        if (skb)
                skb_hwtstamps(skb)->hwtstamp = kvaser_usb_hydra_ktime_from_cmd(dev->cfg, cmd);
        len = can_get_echo_skb(priv->netdev, context->echo_index, NULL);
        context->echo_index = dev->max_tx_urbs;
        --priv->active_tx_contexts;
        netif_wake_queue(priv->netdev);

        spin_unlock_irqrestore(&priv->tx_contexts_lock, irq_flags);

        if (!one_shot_fail && !is_err_frame) {
                struct net_device_stats *stats = &priv->netdev->stats;

                stats->tx_packets++;
                stats->tx_bytes += len;
        }
}

static void kvaser_usb_hydra_rx_msg_std(const struct kvaser_usb *dev,
                                        const struct kvaser_cmd *cmd)
{
        struct kvaser_usb_net_priv *priv = NULL;
        struct can_frame *cf;
        struct sk_buff *skb;
        struct skb_shared_hwtstamps *shhwtstamps;
        struct net_device_stats *stats;
        u8 flags;
        ktime_t hwtstamp;

        priv = kvaser_usb_hydra_net_priv_from_cmd(dev, cmd);
        if (!priv)
                return;

        stats = &priv->netdev->stats;

        flags = cmd->rx_can.flags;
        hwtstamp = kvaser_usb_hydra_ktime_from_cmd(dev->cfg, cmd);

        if (flags & KVASER_USB_HYDRA_CF_FLAG_ERROR_FRAME) {
                kvaser_usb_hydra_error_frame(priv, &cmd->rx_can.err_frame_data,
                                             hwtstamp);
                return;
        }

        skb = alloc_can_skb(priv->netdev, &cf);
        if (!skb) {
                stats->rx_dropped++;
                return;
        }

        shhwtstamps = skb_hwtstamps(skb);
        shhwtstamps->hwtstamp = hwtstamp;

        cf->can_id = le32_to_cpu(cmd->rx_can.id);

        if (cf->can_id &  KVASER_USB_HYDRA_EXTENDED_FRAME_ID) {
                cf->can_id &= CAN_EFF_MASK;
                cf->can_id |= CAN_EFF_FLAG;
        } else {
                cf->can_id &= CAN_SFF_MASK;
        }

        if (flags & KVASER_USB_HYDRA_CF_FLAG_OVERRUN)
                kvaser_usb_can_rx_over_error(priv->netdev);

        can_frame_set_cc_len((struct can_frame *)cf, cmd->rx_can.dlc, priv->can.ctrlmode);

        if (flags & KVASER_USB_HYDRA_CF_FLAG_REMOTE_FRAME) {
                cf->can_id |= CAN_RTR_FLAG;
        } else {
                memcpy(cf->data, cmd->rx_can.data, cf->len);

                stats->rx_bytes += cf->len;
        }
        stats->rx_packets++;

        netif_rx(skb);
}

static void kvaser_usb_hydra_rx_msg_ext(const struct kvaser_usb *dev,
                                        const struct kvaser_cmd_ext *cmd)
{
        struct kvaser_cmd *std_cmd = (struct kvaser_cmd *)cmd;
        struct kvaser_usb_net_priv *priv;
        struct canfd_frame *cf;
        struct sk_buff *skb;
        struct skb_shared_hwtstamps *shhwtstamps;
        struct net_device_stats *stats;
        u32 flags;
        u8 dlc;
        u32 kcan_header;
        ktime_t hwtstamp;

        priv = kvaser_usb_hydra_net_priv_from_cmd(dev, std_cmd);
        if (!priv)
                return;

        stats = &priv->netdev->stats;

        kcan_header = le32_to_cpu(cmd->rx_can.kcan_header);
        dlc = (kcan_header & KVASER_USB_KCAN_DATA_DLC_MASK) >>
                KVASER_USB_KCAN_DATA_DLC_SHIFT;

        flags = le32_to_cpu(cmd->rx_can.flags);
        hwtstamp = kvaser_usb_hydra_ktime_from_cmd(dev->cfg, std_cmd);

        if (flags & KVASER_USB_HYDRA_CF_FLAG_ERROR_FRAME) {
                kvaser_usb_hydra_error_frame(priv, &cmd->rx_can.err_frame_data,
                                             hwtstamp);
                return;
        }

        if (flags & KVASER_USB_HYDRA_CF_FLAG_FDF)
                skb = alloc_canfd_skb(priv->netdev, &cf);
        else
                skb = alloc_can_skb(priv->netdev, (struct can_frame **)&cf);

        if (!skb) {
                stats->rx_dropped++;
                return;
        }

        shhwtstamps = skb_hwtstamps(skb);
        shhwtstamps->hwtstamp = hwtstamp;

        cf->can_id = le32_to_cpu(cmd->rx_can.id);

        if (flags & KVASER_USB_HYDRA_CF_FLAG_EXTENDED_ID) {
                cf->can_id &= CAN_EFF_MASK;
                cf->can_id |= CAN_EFF_FLAG;
        } else {
                cf->can_id &= CAN_SFF_MASK;
        }

        if (flags & KVASER_USB_HYDRA_CF_FLAG_OVERRUN)
                kvaser_usb_can_rx_over_error(priv->netdev);

        if (flags & KVASER_USB_HYDRA_CF_FLAG_FDF) {
                cf->len = can_fd_dlc2len(dlc);
                if (flags & KVASER_USB_HYDRA_CF_FLAG_BRS)
                        cf->flags |= CANFD_BRS;
                if (flags & KVASER_USB_HYDRA_CF_FLAG_ESI)
                        cf->flags |= CANFD_ESI;
        } else {
                can_frame_set_cc_len((struct can_frame *)cf, dlc, priv->can.ctrlmode);
        }

        if (flags & KVASER_USB_HYDRA_CF_FLAG_REMOTE_FRAME) {
                cf->can_id |= CAN_RTR_FLAG;
        } else {
                memcpy(cf->data, cmd->rx_can.kcan_payload, cf->len);

                stats->rx_bytes += cf->len;
        }
        stats->rx_packets++;

        netif_rx(skb);
}

static void kvaser_usb_hydra_handle_cmd_std(const struct kvaser_usb *dev,
                                            const struct kvaser_cmd *cmd)
{
        switch (cmd->header.cmd_no) {
        case CMD_START_CHIP_RESP:
                kvaser_usb_hydra_start_chip_reply(dev, cmd);
                break;

        case CMD_STOP_CHIP_RESP:
                kvaser_usb_hydra_stop_chip_reply(dev, cmd);
                break;

        case CMD_FLUSH_QUEUE_RESP:
                kvaser_usb_hydra_flush_queue_reply(dev, cmd);
                break;

        case CMD_CHIP_STATE_EVENT:
                kvaser_usb_hydra_state_event(dev, cmd);
                break;

        case CMD_GET_BUSPARAMS_RESP:
                kvaser_usb_hydra_get_busparams_reply(dev, cmd);
                break;

        case CMD_ERROR_EVENT:
                kvaser_usb_hydra_error_event(dev, cmd);
                break;

        case CMD_TX_ACKNOWLEDGE:
                kvaser_usb_hydra_tx_acknowledge(dev, cmd);
                break;

        case CMD_RX_MESSAGE:
                kvaser_usb_hydra_rx_msg_std(dev, cmd);
                break;

        /* Ignored commands */
        case CMD_SET_BUSPARAMS_RESP:
        case CMD_SET_BUSPARAMS_FD_RESP:
        case CMD_LED_ACTION_RESP:
                break;

        default:
                dev_warn(&dev->intf->dev, "Unhandled command (%d)\n",
                         cmd->header.cmd_no);
                break;
        }
}

static void kvaser_usb_hydra_handle_cmd_ext(const struct kvaser_usb *dev,
                                            const struct kvaser_cmd_ext *cmd)
{
        switch (cmd->cmd_no_ext) {
        case CMD_TX_ACKNOWLEDGE_FD:
                kvaser_usb_hydra_tx_acknowledge(dev, (struct kvaser_cmd *)cmd);
                break;

        case CMD_RX_MESSAGE_FD:
                kvaser_usb_hydra_rx_msg_ext(dev, cmd);
                break;

        default:
                dev_warn(&dev->intf->dev, "Unhandled extended command (%d)\n",
                         cmd->header.cmd_no);
                break;
        }
}

static void kvaser_usb_hydra_handle_cmd(const struct kvaser_usb *dev,
                                        const struct kvaser_cmd *cmd)
{
                if (cmd->header.cmd_no == CMD_EXTENDED)
                        kvaser_usb_hydra_handle_cmd_ext
                                        (dev, (struct kvaser_cmd_ext *)cmd);
                else
                        kvaser_usb_hydra_handle_cmd_std(dev, cmd);
}

static void *
kvaser_usb_hydra_frame_to_cmd_ext(const struct kvaser_usb_net_priv *priv,
                                  const struct sk_buff *skb, int *cmd_len,
                                  u16 transid)
{
        struct kvaser_usb *dev = priv->dev;
        struct kvaser_cmd_ext *cmd;
        struct canfd_frame *cf = (struct canfd_frame *)skb->data;
        u8 dlc;
        u8 nbr_of_bytes = cf->len;
        u32 flags;
        u32 id;
        u32 kcan_id;
        u32 kcan_header;

        cmd = kzalloc_obj(*cmd, GFP_ATOMIC);
        if (!cmd)
                return NULL;

        kvaser_usb_hydra_set_cmd_dest_he
                        ((struct kvaser_cmd *)cmd,
                         dev->card_data.hydra.channel_to_he[priv->channel]);
        kvaser_usb_hydra_set_cmd_transid((struct kvaser_cmd *)cmd, transid);

        cmd->header.cmd_no = CMD_EXTENDED;
        cmd->cmd_no_ext = CMD_TX_CAN_MESSAGE_FD;

        *cmd_len = ALIGN(sizeof(struct kvaser_cmd_ext) -
                         sizeof(cmd->tx_can.kcan_payload) + nbr_of_bytes,
                         8);

        cmd->len = cpu_to_le16(*cmd_len);

        if (can_is_canfd_skb(skb))
                dlc = can_fd_len2dlc(cf->len);
        else
                dlc = can_get_cc_dlc((struct can_frame *)cf, priv->can.ctrlmode);

        cmd->tx_can.databytes = nbr_of_bytes;
        cmd->tx_can.dlc = dlc;

        if (cf->can_id & CAN_EFF_FLAG) {
                id = cf->can_id & CAN_EFF_MASK;
                flags = KVASER_USB_HYDRA_CF_FLAG_EXTENDED_ID;
                kcan_id = (cf->can_id & CAN_EFF_MASK) |
                          KVASER_USB_KCAN_DATA_IDE | KVASER_USB_KCAN_DATA_SRR;
        } else {
                id = cf->can_id & CAN_SFF_MASK;
                flags = 0;
                kcan_id = cf->can_id & CAN_SFF_MASK;
        }

        if (cf->can_id & CAN_ERR_FLAG)
                flags |= KVASER_USB_HYDRA_CF_FLAG_ERROR_FRAME;

        kcan_header = ((dlc << KVASER_USB_KCAN_DATA_DLC_SHIFT) &
                                KVASER_USB_KCAN_DATA_DLC_MASK) |
                        KVASER_USB_KCAN_DATA_AREQ |
                        (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT ?
                                KVASER_USB_KCAN_DATA_OSM : 0);

        if (can_is_canfd_skb(skb)) {
                kcan_header |= KVASER_USB_KCAN_DATA_FDF |
                               (cf->flags & CANFD_BRS ?
                                        KVASER_USB_KCAN_DATA_BRS : 0);
        } else {
                if (cf->can_id & CAN_RTR_FLAG) {
                        kcan_id |= KVASER_USB_KCAN_DATA_RTR;
                        cmd->tx_can.databytes = 0;
                        flags |= KVASER_USB_HYDRA_CF_FLAG_REMOTE_FRAME;
                }
        }

        cmd->tx_can.kcan_id = cpu_to_le32(kcan_id);
        cmd->tx_can.id = cpu_to_le32(id);
        cmd->tx_can.flags = cpu_to_le32(flags);
        cmd->tx_can.kcan_header = cpu_to_le32(kcan_header);

        memcpy(cmd->tx_can.kcan_payload, cf->data, nbr_of_bytes);

        return cmd;
}

static void *
kvaser_usb_hydra_frame_to_cmd_std(const struct kvaser_usb_net_priv *priv,
                                  const struct sk_buff *skb, int *cmd_len,
                                  u16 transid)
{
        struct kvaser_usb *dev = priv->dev;
        struct kvaser_cmd *cmd;
        struct can_frame *cf = (struct can_frame *)skb->data;
        u32 flags;
        u32 id;

        cmd = kzalloc_obj(*cmd, GFP_ATOMIC);
        if (!cmd)
                return NULL;

        kvaser_usb_hydra_set_cmd_dest_he
                (cmd, dev->card_data.hydra.channel_to_he[priv->channel]);
        kvaser_usb_hydra_set_cmd_transid(cmd, transid);

        cmd->header.cmd_no = CMD_TX_CAN_MESSAGE;

        *cmd_len = ALIGN(sizeof(struct kvaser_cmd), 8);

        if (cf->can_id & CAN_EFF_FLAG) {
                id = (cf->can_id & CAN_EFF_MASK);
                id |= KVASER_USB_HYDRA_EXTENDED_FRAME_ID;
        } else {
                id = cf->can_id & CAN_SFF_MASK;
        }

        cmd->tx_can.dlc = can_get_cc_dlc(cf, priv->can.ctrlmode);

        flags = (cf->can_id & CAN_EFF_FLAG ?
                 KVASER_USB_HYDRA_CF_FLAG_EXTENDED_ID : 0);

        if (cf->can_id & CAN_RTR_FLAG)
                flags |= KVASER_USB_HYDRA_CF_FLAG_REMOTE_FRAME;

        flags |= (cf->can_id & CAN_ERR_FLAG ?
                  KVASER_USB_HYDRA_CF_FLAG_ERROR_FRAME : 0);

        cmd->tx_can.id = cpu_to_le32(id);
        cmd->tx_can.flags = flags;

        memcpy(cmd->tx_can.data, cf->data, cf->len);

        return cmd;
}

static int kvaser_usb_hydra_set_mode(struct net_device *netdev,
                                     enum can_mode mode)
{
        int err = 0;

        switch (mode) {
        case CAN_MODE_START:
                /* CAN controller automatically recovers from BUS_OFF */
                break;
        default:
                err = -EOPNOTSUPP;
        }

        return err;
}

static int kvaser_usb_hydra_get_busparams(struct kvaser_usb_net_priv *priv,
                                          int busparams_type)
{
        struct kvaser_usb *dev = priv->dev;
        struct kvaser_usb_net_hydra_priv *hydra = priv->sub_priv;
        struct kvaser_cmd *cmd;
        size_t cmd_len;
        int err;

        if (!hydra)
                return -EINVAL;

        cmd = kzalloc_objs(struct kvaser_cmd, 1);
        if (!cmd)
                return -ENOMEM;

        cmd->header.cmd_no = CMD_GET_BUSPARAMS_REQ;
        cmd_len = kvaser_usb_hydra_cmd_size(cmd);
        kvaser_usb_hydra_set_cmd_dest_he
                (cmd, dev->card_data.hydra.channel_to_he[priv->channel]);
        kvaser_usb_hydra_set_cmd_transid
                                (cmd, kvaser_usb_hydra_get_next_transid(dev));
        cmd->get_busparams_req.type = busparams_type;
        hydra->pending_get_busparams_type = busparams_type;

        reinit_completion(&priv->get_busparams_comp);

        err = kvaser_usb_send_cmd(dev, cmd, cmd_len);
        if (err)
                return err;

        if (!wait_for_completion_timeout(&priv->get_busparams_comp,
                                         msecs_to_jiffies(KVASER_USB_TIMEOUT)))
                return -ETIMEDOUT;

        return err;
}

static int kvaser_usb_hydra_get_nominal_busparams(struct kvaser_usb_net_priv *priv)
{
        return kvaser_usb_hydra_get_busparams(priv, KVASER_USB_HYDRA_BUSPARAM_TYPE_CAN);
}

static int kvaser_usb_hydra_get_data_busparams(struct kvaser_usb_net_priv *priv)
{
        return kvaser_usb_hydra_get_busparams(priv, KVASER_USB_HYDRA_BUSPARAM_TYPE_CANFD);
}

static int kvaser_usb_hydra_set_bittiming(const struct net_device *netdev,
                                          const struct kvaser_usb_busparams *busparams)
{
        struct kvaser_cmd *cmd;
        struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
        struct kvaser_usb *dev = priv->dev;
        size_t cmd_len;
        int err;

        cmd = kzalloc_obj(*cmd);
        if (!cmd)
                return -ENOMEM;

        cmd->header.cmd_no = CMD_SET_BUSPARAMS_REQ;
        cmd_len = kvaser_usb_hydra_cmd_size(cmd);
        memcpy(&cmd->set_busparams_req.busparams_nominal, busparams,
               sizeof(cmd->set_busparams_req.busparams_nominal));

        kvaser_usb_hydra_set_cmd_dest_he
                (cmd, dev->card_data.hydra.channel_to_he[priv->channel]);
        kvaser_usb_hydra_set_cmd_transid
                                (cmd, kvaser_usb_hydra_get_next_transid(dev));

        err = kvaser_usb_send_cmd(dev, cmd, cmd_len);

        kfree(cmd);

        return err;
}

static int kvaser_usb_hydra_set_data_bittiming(const struct net_device *netdev,
                                               const struct kvaser_usb_busparams *busparams)
{
        struct kvaser_cmd *cmd;
        struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
        struct kvaser_usb *dev = priv->dev;
        size_t cmd_len;
        int err;

        cmd = kzalloc_obj(*cmd);
        if (!cmd)
                return -ENOMEM;

        cmd->header.cmd_no = CMD_SET_BUSPARAMS_FD_REQ;
        cmd_len = kvaser_usb_hydra_cmd_size(cmd);
        memcpy(&cmd->set_busparams_req.busparams_data, busparams,
               sizeof(cmd->set_busparams_req.busparams_data));

        if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
                if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
                        cmd->set_busparams_req.canfd_mode =
                                        KVASER_USB_HYDRA_BUS_MODE_NONISO;
                else
                        cmd->set_busparams_req.canfd_mode =
                                        KVASER_USB_HYDRA_BUS_MODE_CANFD_ISO;
        }

        kvaser_usb_hydra_set_cmd_dest_he
                (cmd, dev->card_data.hydra.channel_to_he[priv->channel]);
        kvaser_usb_hydra_set_cmd_transid
                                (cmd, kvaser_usb_hydra_get_next_transid(dev));

        err = kvaser_usb_send_cmd(dev, cmd, cmd_len);

        kfree(cmd);

        return err;
}

static int kvaser_usb_hydra_get_berr_counter(const struct net_device *netdev,
                                             struct can_berr_counter *bec)
{
        struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
        int err;

        err = kvaser_usb_hydra_send_simple_cmd(priv->dev,
                                               CMD_GET_CHIP_STATE_REQ,
                                               priv->channel);
        if (err)
                return err;

        *bec = priv->bec;

        return 0;
}

static int kvaser_usb_hydra_setup_endpoints(struct kvaser_usb *dev)
{
        const struct usb_host_interface *iface_desc;
        struct usb_endpoint_descriptor *ep;
        int i;

        iface_desc = dev->intf->cur_altsetting;

        for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
                ep = &iface_desc->endpoint[i].desc;

                if (!dev->bulk_in && usb_endpoint_is_bulk_in(ep) &&
                    ep->bEndpointAddress == KVASER_USB_HYDRA_BULK_EP_IN_ADDR)
                        dev->bulk_in = ep;

                if (!dev->bulk_out && usb_endpoint_is_bulk_out(ep) &&
                    ep->bEndpointAddress == KVASER_USB_HYDRA_BULK_EP_OUT_ADDR)
                        dev->bulk_out = ep;

                if (dev->bulk_in && dev->bulk_out)
                        return 0;
        }

        return -ENODEV;
}

static int kvaser_usb_hydra_init_card(struct kvaser_usb *dev)
{
        int err;
        unsigned int i;
        struct kvaser_usb_dev_card_data_hydra *card_data =
                                                        &dev->card_data.hydra;

        card_data->transid = KVASER_USB_HYDRA_MIN_TRANSID;
        spin_lock_init(&card_data->transid_lock);

        memset(card_data->usb_rx_leftover, 0, KVASER_USB_HYDRA_MAX_CMD_LEN);
        card_data->usb_rx_leftover_len = 0;
        spin_lock_init(&card_data->usb_rx_leftover_lock);

        memset(card_data->channel_to_he, KVASER_USB_HYDRA_HE_ADDRESS_ILLEGAL,
               sizeof(card_data->channel_to_he));
        card_data->sysdbg_he = 0;

        for (i = 0; i < KVASER_USB_MAX_NET_DEVICES; i++) {
                err = kvaser_usb_hydra_map_channel
                                        (dev,
                                         (KVASER_USB_HYDRA_TRANSID_CANHE | i),
                                         i, "CAN");
                if (err) {
                        dev_err(&dev->intf->dev,
                                "CMD_MAP_CHANNEL_REQ failed for CAN%u\n", i);
                        return err;
                }
        }

        err = kvaser_usb_hydra_map_channel(dev, KVASER_USB_HYDRA_TRANSID_SYSDBG,
                                           0, "SYSDBG");
        if (err) {
                dev_err(&dev->intf->dev,
                        "CMD_MAP_CHANNEL_REQ failed for SYSDBG\n");
                return err;
        }

        return 0;
}

static int kvaser_usb_hydra_init_channel(struct kvaser_usb_net_priv *priv)
{
        struct kvaser_usb_net_hydra_priv *hydra;

        hydra = devm_kzalloc(&priv->dev->intf->dev, sizeof(*hydra), GFP_KERNEL);
        if (!hydra)
                return -ENOMEM;

        priv->sub_priv = hydra;

        return 0;
}

static int kvaser_usb_hydra_get_software_info(struct kvaser_usb *dev)
{
        struct kvaser_cmd cmd;
        int err;

        err = kvaser_usb_hydra_send_simple_cmd(dev, CMD_GET_SOFTWARE_INFO_REQ,
                                               -1);
        if (err)
                return err;

        memset(&cmd, 0, sizeof(struct kvaser_cmd));
        err = kvaser_usb_hydra_wait_cmd(dev, CMD_GET_SOFTWARE_INFO_RESP, &cmd);
        if (err)
                return err;

        dev->max_tx_urbs = min_t(unsigned int, KVASER_USB_MAX_TX_URBS,
                                 le16_to_cpu(cmd.sw_info.max_outstanding_tx));

        return 0;
}

static int kvaser_usb_hydra_get_software_details(struct kvaser_usb *dev)
{
        struct kvaser_cmd *cmd;
        size_t cmd_len;
        int err;
        u32 flags;
        u32 fw_version;
        struct kvaser_usb_dev_card_data *card_data = &dev->card_data;

        cmd = kzalloc_obj(*cmd);
        if (!cmd)
                return -ENOMEM;

        cmd->header.cmd_no = CMD_GET_SOFTWARE_DETAILS_REQ;
        cmd_len = kvaser_usb_hydra_cmd_size(cmd);
        cmd->sw_detail_req.use_ext_cmd = 1;
        kvaser_usb_hydra_set_cmd_dest_he
                                (cmd, KVASER_USB_HYDRA_HE_ADDRESS_ILLEGAL);

        kvaser_usb_hydra_set_cmd_transid
                                (cmd, kvaser_usb_hydra_get_next_transid(dev));

        err = kvaser_usb_send_cmd(dev, cmd, cmd_len);
        if (err)
                goto end;

        err = kvaser_usb_hydra_wait_cmd(dev, CMD_GET_SOFTWARE_DETAILS_RESP,
                                        cmd);
        if (err)
                goto end;

        fw_version = le32_to_cpu(cmd->sw_detail_res.sw_version);
        dev->fw_version.major = FIELD_GET(KVASER_USB_SW_VERSION_MAJOR_MASK, fw_version);
        dev->fw_version.minor = FIELD_GET(KVASER_USB_SW_VERSION_MINOR_MASK, fw_version);
        dev->fw_version.build = FIELD_GET(KVASER_USB_SW_VERSION_BUILD_MASK, fw_version);
        flags = le32_to_cpu(cmd->sw_detail_res.sw_flags);

        if (flags & KVASER_USB_HYDRA_SW_FLAG_FW_BAD) {
                dev_err(&dev->intf->dev,
                        "Bad firmware, device refuse to run!\n");
                err = -EINVAL;
                goto end;
        }

        if (flags & KVASER_USB_HYDRA_SW_FLAG_FW_BETA)
                dev_info(&dev->intf->dev, "Beta firmware in use\n");

        if (flags & KVASER_USB_HYDRA_SW_FLAG_EXT_CAP)
                card_data->capabilities |= KVASER_USB_CAP_EXT_CAP;

        if (flags & KVASER_USB_HYDRA_SW_FLAG_EXT_CMD)
                card_data->capabilities |= KVASER_USB_HYDRA_CAP_EXT_CMD;

        if (flags & KVASER_USB_HYDRA_SW_FLAG_CANFD)
                card_data->ctrlmode_supported |= CAN_CTRLMODE_FD;

        if (flags & KVASER_USB_HYDRA_SW_FLAG_NONISO)
                card_data->ctrlmode_supported |= CAN_CTRLMODE_FD_NON_ISO;

        if (flags &  KVASER_USB_HYDRA_SW_FLAG_FREQ_80M)
                dev->cfg = &kvaser_usb_hydra_dev_cfg_kcan;
        else if (flags & KVASER_USB_HYDRA_SW_FLAG_CAN_FREQ_80M)
                dev->cfg = &kvaser_usb_hydra_dev_cfg_rt;
        else
                dev->cfg = &kvaser_usb_hydra_dev_cfg_flexc;

end:
        kfree(cmd);

        return err;
}

static int kvaser_usb_hydra_get_card_info(struct kvaser_usb *dev)
{
        struct kvaser_cmd cmd;
        int err;

        err = kvaser_usb_hydra_send_simple_cmd(dev, CMD_GET_CARD_INFO_REQ, -1);
        if (err)
                return err;

        memset(&cmd, 0, sizeof(struct kvaser_cmd));
        err = kvaser_usb_hydra_wait_cmd(dev, CMD_GET_CARD_INFO_RESP, &cmd);
        if (err)
                return err;
        dev->ean[1] = le32_to_cpu(cmd.card_info.ean[1]);
        dev->ean[0] = le32_to_cpu(cmd.card_info.ean[0]);
        dev->serial_number = le32_to_cpu(cmd.card_info.serial_number);
        dev->hw_revision = cmd.card_info.hw_revision;

        dev->nchannels = cmd.card_info.nchannels;
        if (dev->nchannels > KVASER_USB_MAX_NET_DEVICES)
                return -EINVAL;

        return 0;
}

static int kvaser_usb_hydra_get_capabilities(struct kvaser_usb *dev)
{
        int err;
        u16 status;

        if (!(dev->card_data.capabilities & KVASER_USB_CAP_EXT_CAP)) {
                dev_info(&dev->intf->dev,
                         "No extended capability support. Upgrade your device.\n");
                return 0;
        }

        err = kvaser_usb_hydra_get_single_capability
                                        (dev,
                                         KVASER_USB_HYDRA_CAP_CMD_LISTEN_MODE,
                                         &status);
        if (err)
                return err;
        if (status)
                dev_info(&dev->intf->dev,
                         "KVASER_USB_HYDRA_CAP_CMD_LISTEN_MODE failed %u\n",
                         status);

        err = kvaser_usb_hydra_get_single_capability
                                        (dev,
                                         KVASER_USB_HYDRA_CAP_CMD_ERR_REPORT,
                                         &status);
        if (err)
                return err;
        if (status)
                dev_info(&dev->intf->dev,
                         "KVASER_USB_HYDRA_CAP_CMD_ERR_REPORT failed %u\n",
                         status);

        err = kvaser_usb_hydra_get_single_capability
                                        (dev, KVASER_USB_HYDRA_CAP_CMD_ONE_SHOT,
                                         &status);
        if (err)
                return err;
        if (status)
                dev_info(&dev->intf->dev,
                         "KVASER_USB_HYDRA_CAP_CMD_ONE_SHOT failed %u\n",
                         status);

        return 0;
}

static int kvaser_usb_hydra_set_led(struct kvaser_usb_net_priv *priv,
                                    enum kvaser_usb_led_state state,
                                    u16 duration_ms)
{
        struct kvaser_usb *dev = priv->dev;
        struct kvaser_cmd *cmd;
        size_t cmd_len;
        int ret;

        cmd = kzalloc_obj(*cmd);
        if (!cmd)
                return -ENOMEM;

        cmd->header.cmd_no = CMD_LED_ACTION_REQ;
        cmd_len = kvaser_usb_hydra_cmd_size(cmd);
        kvaser_usb_hydra_set_cmd_dest_he(cmd, dev->card_data.hydra.sysdbg_he);
        kvaser_usb_hydra_set_cmd_transid(cmd, kvaser_usb_hydra_get_next_transid(dev));

        cmd->led_action_req.duration_ms = cpu_to_le16(duration_ms);
        cmd->led_action_req.action = state |
                                     FIELD_PREP(KVASER_USB_HYDRA_LED_IDX_MASK,
                                                KVASER_USB_HYDRA_LED_YELLOW_CH0_IDX +
                                                KVASER_USB_HYDRA_LEDS_PER_CHANNEL * priv->channel);

        ret = kvaser_usb_send_cmd(dev, cmd, cmd_len);
        kfree(cmd);

        return ret;
}

static int kvaser_usb_hydra_set_opt_mode(const struct kvaser_usb_net_priv *priv)
{
        struct kvaser_usb *dev = priv->dev;
        struct kvaser_cmd *cmd;
        size_t cmd_len;
        int err;

        if ((priv->can.ctrlmode &
            (CAN_CTRLMODE_FD | CAN_CTRLMODE_FD_NON_ISO)) ==
            CAN_CTRLMODE_FD_NON_ISO) {
                netdev_warn(priv->netdev,
                            "CTRLMODE_FD shall be on if CTRLMODE_FD_NON_ISO is on\n");
                return -EINVAL;
        }

        cmd = kzalloc_obj(*cmd);
        if (!cmd)
                return -ENOMEM;

        cmd->header.cmd_no = CMD_SET_DRIVERMODE_REQ;
        cmd_len = kvaser_usb_hydra_cmd_size(cmd);
        kvaser_usb_hydra_set_cmd_dest_he
                (cmd, dev->card_data.hydra.channel_to_he[priv->channel]);
        kvaser_usb_hydra_set_cmd_transid
                                (cmd, kvaser_usb_hydra_get_next_transid(dev));
        if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
                cmd->set_ctrlmode.mode = KVASER_USB_HYDRA_CTRLMODE_LISTEN;
        else
                cmd->set_ctrlmode.mode = KVASER_USB_HYDRA_CTRLMODE_NORMAL;

        err = kvaser_usb_send_cmd(dev, cmd, cmd_len);
        kfree(cmd);

        return err;
}

static int kvaser_usb_hydra_start_chip(struct kvaser_usb_net_priv *priv)
{
        int err;

        reinit_completion(&priv->start_comp);

        err = kvaser_usb_hydra_send_simple_cmd(priv->dev, CMD_START_CHIP_REQ,
                                               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_hydra_stop_chip(struct kvaser_usb_net_priv *priv)
{
        int err;

        reinit_completion(&priv->stop_comp);

        /* Make sure we do not report invalid BUS_OFF from CMD_CHIP_STATE_EVENT
         * see comment in kvaser_usb_hydra_update_state()
         */
        priv->can.state = CAN_STATE_STOPPED;

        err = kvaser_usb_hydra_send_simple_cmd(priv->dev, CMD_STOP_CHIP_REQ,
                                               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_hydra_flush_queue(struct kvaser_usb_net_priv *priv)
{
        int err;

        reinit_completion(&priv->flush_comp);

        err = kvaser_usb_hydra_send_simple_cmd(priv->dev, CMD_FLUSH_QUEUE,
                                               priv->channel);
        if (err)
                return err;

        if (!wait_for_completion_timeout(&priv->flush_comp,
                                         msecs_to_jiffies(KVASER_USB_TIMEOUT)))
                return -ETIMEDOUT;

        return 0;
}

/* A single extended hydra command can be transmitted in multiple transfers
 * We have to buffer partial hydra commands, and handle them on next callback.
 */
static void kvaser_usb_hydra_read_bulk_callback(struct kvaser_usb *dev,
                                                void *buf, int len)
{
        unsigned long irq_flags;
        struct kvaser_cmd *cmd;
        int pos = 0;
        size_t cmd_len;
        struct kvaser_usb_dev_card_data_hydra *card_data =
                                                        &dev->card_data.hydra;
        int usb_rx_leftover_len;
        spinlock_t *usb_rx_leftover_lock = &card_data->usb_rx_leftover_lock;

        spin_lock_irqsave(usb_rx_leftover_lock, irq_flags);
        usb_rx_leftover_len = card_data->usb_rx_leftover_len;
        if (usb_rx_leftover_len) {
                int remaining_bytes;

                cmd = (struct kvaser_cmd *)card_data->usb_rx_leftover;

                cmd_len = kvaser_usb_hydra_cmd_size(cmd);

                remaining_bytes = min_t(unsigned int, len,
                                        cmd_len - usb_rx_leftover_len);
                /* Make sure we do not overflow usb_rx_leftover */
                if (remaining_bytes + usb_rx_leftover_len >
                                                KVASER_USB_HYDRA_MAX_CMD_LEN) {
                        dev_err(&dev->intf->dev, "Format error\n");
                        spin_unlock_irqrestore(usb_rx_leftover_lock, irq_flags);
                        return;
                }

                memcpy(card_data->usb_rx_leftover + usb_rx_leftover_len, buf,
                       remaining_bytes);
                pos += remaining_bytes;

                if (remaining_bytes + usb_rx_leftover_len == cmd_len) {
                        kvaser_usb_hydra_handle_cmd(dev, cmd);
                        usb_rx_leftover_len = 0;
                } else {
                        /* Command still not complete */
                        usb_rx_leftover_len += remaining_bytes;
                }
                card_data->usb_rx_leftover_len = usb_rx_leftover_len;
        }
        spin_unlock_irqrestore(usb_rx_leftover_lock, irq_flags);

        while (pos < len) {
                cmd = buf + pos;

                cmd_len = kvaser_usb_hydra_cmd_size(cmd);

                if (pos + cmd_len > len) {
                        /* We got first part of a command */
                        int leftover_bytes;

                        leftover_bytes = len - pos;
                        /* Make sure we do not overflow usb_rx_leftover */
                        if (leftover_bytes > KVASER_USB_HYDRA_MAX_CMD_LEN) {
                                dev_err(&dev->intf->dev, "Format error\n");
                                return;
                        }
                        spin_lock_irqsave(usb_rx_leftover_lock, irq_flags);
                        memcpy(card_data->usb_rx_leftover, buf + pos,
                               leftover_bytes);
                        card_data->usb_rx_leftover_len = leftover_bytes;
                        spin_unlock_irqrestore(usb_rx_leftover_lock, irq_flags);
                        break;
                }

                kvaser_usb_hydra_handle_cmd(dev, cmd);
                pos += cmd_len;
        }
}

static void *
kvaser_usb_hydra_frame_to_cmd(const struct kvaser_usb_net_priv *priv,
                              const struct sk_buff *skb, int *cmd_len,
                              u16 transid)
{
        void *buf;

        if (priv->dev->card_data.capabilities & KVASER_USB_HYDRA_CAP_EXT_CMD)
                buf = kvaser_usb_hydra_frame_to_cmd_ext(priv, skb, cmd_len,
                                                        transid);
        else
                buf = kvaser_usb_hydra_frame_to_cmd_std(priv, skb, cmd_len,
                                                        transid);

        return buf;
}

const struct kvaser_usb_dev_ops kvaser_usb_hydra_dev_ops = {
        .dev_set_mode = kvaser_usb_hydra_set_mode,
        .dev_set_bittiming = kvaser_usb_hydra_set_bittiming,
        .dev_get_busparams = kvaser_usb_hydra_get_nominal_busparams,
        .dev_set_data_bittiming = kvaser_usb_hydra_set_data_bittiming,
        .dev_get_data_busparams = kvaser_usb_hydra_get_data_busparams,
        .dev_get_berr_counter = kvaser_usb_hydra_get_berr_counter,
        .dev_setup_endpoints = kvaser_usb_hydra_setup_endpoints,
        .dev_init_card = kvaser_usb_hydra_init_card,
        .dev_init_channel = kvaser_usb_hydra_init_channel,
        .dev_get_software_info = kvaser_usb_hydra_get_software_info,
        .dev_get_software_details = kvaser_usb_hydra_get_software_details,
        .dev_get_card_info = kvaser_usb_hydra_get_card_info,
        .dev_get_capabilities = kvaser_usb_hydra_get_capabilities,
        .dev_set_led = kvaser_usb_hydra_set_led,
        .dev_set_opt_mode = kvaser_usb_hydra_set_opt_mode,
        .dev_start_chip = kvaser_usb_hydra_start_chip,
        .dev_stop_chip = kvaser_usb_hydra_stop_chip,
        .dev_reset_chip = NULL,
        .dev_flush_queue = kvaser_usb_hydra_flush_queue,
        .dev_read_bulk_callback = kvaser_usb_hydra_read_bulk_callback,
        .dev_frame_to_cmd = kvaser_usb_hydra_frame_to_cmd,
};

static const struct kvaser_usb_dev_cfg kvaser_usb_hydra_dev_cfg_kcan = {
        .clock = {
                .freq = 80 * MEGA /* Hz */,
        },
        .timestamp_freq = 80,
        .bittiming_const = &kvaser_usb_hydra_kcan_bittiming_c,
        .data_bittiming_const = &kvaser_usb_hydra_kcan_bittiming_c,
};

static const struct kvaser_usb_dev_cfg kvaser_usb_hydra_dev_cfg_flexc = {
        .clock = {
                .freq = 24 * MEGA /* Hz */,
        },
        .timestamp_freq = 1,
        .bittiming_const = &kvaser_usb_flexc_bittiming_const,
};

static const struct kvaser_usb_dev_cfg kvaser_usb_hydra_dev_cfg_rt = {
        .clock = {
                .freq = 80 * MEGA /* Hz */,
        },
        .timestamp_freq = 24,
        .bittiming_const = &kvaser_usb_hydra_rt_bittiming_c,
        .data_bittiming_const = &kvaser_usb_hydra_rtd_bittiming_c,
};