Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-only
/* SocketCAN driver for Microchip CAN BUS Analyzer Tool
 *
 * Copyright (C) 2017 Mobica Limited
 *
 * This driver is inspired by the 4.6.2 version of net/can/usb/usb_8dev.c
 */
 
#include <asm/unaligned.h>
#include <linux/can.h>
#include <linux/can/dev.h>
#include <linux/can/error.h>
#include <linux/can/led.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/signal.h>
#include <linux/slab.h>
#include <linux/usb.h>
 
/* vendor and product id */
#define MCBA_MODULE_NAME "mcba_usb"
#define MCBA_VENDOR_ID 0x04d8
#define MCBA_PRODUCT_ID 0x0a30
 
/* driver constants */
#define MCBA_MAX_RX_URBS 20
#define MCBA_MAX_TX_URBS 20
#define MCBA_CTX_FREE MCBA_MAX_TX_URBS
 
/* RX buffer must be bigger than msg size since at the
 * beginning USB messages are stacked.
 */
#define MCBA_USB_RX_BUFF_SIZE 64
#define MCBA_USB_TX_BUFF_SIZE (sizeof(struct mcba_usb_msg))
 
/* Microchip command id */
#define MBCA_CMD_RECEIVE_MESSAGE 0xE3
#define MBCA_CMD_I_AM_ALIVE_FROM_CAN 0xF5
#define MBCA_CMD_I_AM_ALIVE_FROM_USB 0xF7
#define MBCA_CMD_CHANGE_BIT_RATE 0xA1
#define MBCA_CMD_TRANSMIT_MESSAGE_EV 0xA3
#define MBCA_CMD_SETUP_TERMINATION_RESISTANCE 0xA8
#define MBCA_CMD_READ_FW_VERSION 0xA9
#define MBCA_CMD_NOTHING_TO_SEND 0xFF
#define MBCA_CMD_TRANSMIT_MESSAGE_RSP 0xE2
 
#define MCBA_VER_REQ_USB 1
#define MCBA_VER_REQ_CAN 2
 
#define MCBA_SIDL_EXID_MASK 0x8
#define MCBA_DLC_MASK 0xf
#define MCBA_DLC_RTR_MASK 0x40
 
#define MCBA_CAN_STATE_WRN_TH 95
#define MCBA_CAN_STATE_ERR_PSV_TH 127
 
#define MCBA_TERMINATION_DISABLED CAN_TERMINATION_DISABLED
#define MCBA_TERMINATION_ENABLED 120
 
struct mcba_usb_ctx {
<------>struct mcba_priv *priv;
<------>u32 ndx;
<------>u8 dlc;
<------>bool can;
};
 
/* Structure to hold all of our device specific stuff */
struct mcba_priv {
<------>struct can_priv can; /* must be the first member */
<------>struct sk_buff *echo_skb[MCBA_MAX_TX_URBS];
<------>struct mcba_usb_ctx tx_context[MCBA_MAX_TX_URBS];
<------>struct usb_device *udev;
<------>struct net_device *netdev;
<------>struct usb_anchor tx_submitted;
<------>struct usb_anchor rx_submitted;
<------>struct can_berr_counter bec;
<------>bool usb_ka_first_pass;
<------>bool can_ka_first_pass;
<------>bool can_speed_check;
<------>atomic_t free_ctx_cnt;
<------>void *rxbuf[MCBA_MAX_RX_URBS];
<------>dma_addr_t rxbuf_dma[MCBA_MAX_RX_URBS];
<------>int rx_pipe;
<------>int tx_pipe;
};
 
/* CAN frame */
struct __packed mcba_usb_msg_can {
<------>u8 cmd_id;
<------>__be16 eid;
<------>__be16 sid;
<------>u8 dlc;
<------>u8 data[8];
<------>u8 timestamp[4];
<------>u8 checksum;
};
 
/* command frame */
struct __packed mcba_usb_msg {
<------>u8 cmd_id;
<------>u8 unused[18];
};
 
struct __packed mcba_usb_msg_ka_usb {
<------>u8 cmd_id;
<------>u8 termination_state;
<------>u8 soft_ver_major;
<------>u8 soft_ver_minor;
<------>u8 unused[15];
};
 
struct __packed mcba_usb_msg_ka_can {
<------>u8 cmd_id;
<------>u8 tx_err_cnt;
<------>u8 rx_err_cnt;
<------>u8 rx_buff_ovfl;
<------>u8 tx_bus_off;
<------>__be16 can_bitrate;
<------>__le16 rx_lost;
<------>u8 can_stat;
<------>u8 soft_ver_major;
<------>u8 soft_ver_minor;
<------>u8 debug_mode;
<------>u8 test_complete;
<------>u8 test_result;
<------>u8 unused[4];
};
 
struct __packed mcba_usb_msg_change_bitrate {
<------>u8 cmd_id;
<------>__be16 bitrate;
<------>u8 unused[16];
};
 
struct __packed mcba_usb_msg_termination {
<------>u8 cmd_id;
<------>u8 termination;
<------>u8 unused[17];
};
 
struct __packed mcba_usb_msg_fw_ver {
<------>u8 cmd_id;
<------>u8 pic;
<------>u8 unused[17];
};
 
static const struct usb_device_id mcba_usb_table[] = {
<------>{ USB_DEVICE(MCBA_VENDOR_ID, MCBA_PRODUCT_ID) },
<------>{} /* Terminating entry */
};
 
MODULE_DEVICE_TABLE(usb, mcba_usb_table);
 
static const u16 mcba_termination[] = { MCBA_TERMINATION_DISABLED,
<------><------><------><------><------>MCBA_TERMINATION_ENABLED };
 
static const u32 mcba_bitrate[] = { 20000,  33333,  50000,  80000,  83333,
<------><------><------><------>    100000, 125000, 150000, 175000, 200000,
<------><------><------><------>    225000, 250000, 275000, 300000, 500000,
<------><------><------><------>    625000, 800000, 1000000 };
 
static inline void mcba_init_ctx(struct mcba_priv *priv)
{
<------>int i = 0;
 
<------>for (i = 0; i < MCBA_MAX_TX_URBS; i++) {
<------><------>priv->tx_context[i].ndx = MCBA_CTX_FREE;
<------><------>priv->tx_context[i].priv = priv;
<------>}
 
<------>atomic_set(&priv->free_ctx_cnt, ARRAY_SIZE(priv->tx_context));
}
 
static inline struct mcba_usb_ctx *mcba_usb_get_free_ctx(struct mcba_priv *priv,
<------><------><------><------><------><------><------> struct can_frame *cf)
{
<------>int i = 0;
<------>struct mcba_usb_ctx *ctx = NULL;
 
<------>for (i = 0; i < MCBA_MAX_TX_URBS; i++) {
<------><------>if (priv->tx_context[i].ndx == MCBA_CTX_FREE) {
<------><------><------>ctx = &priv->tx_context[i];
<------><------><------>ctx->ndx = i;
 
<------><------><------>if (cf) {
<------><------><------><------>ctx->can = true;
<------><------><------><------>ctx->dlc = cf->can_dlc;
<------><------><------>} else {
<------><------><------><------>ctx->can = false;
<------><------><------><------>ctx->dlc = 0;
<------><------><------>}
 
<------><------><------>atomic_dec(&priv->free_ctx_cnt);
<------><------><------>break;
<------><------>}
<------>}
 
<------>if (!atomic_read(&priv->free_ctx_cnt))
<------><------>/* That was the last free ctx. Slow down tx path */
<------><------>netif_stop_queue(priv->netdev);
 
<------>return ctx;
}
 
/* mcba_usb_free_ctx and mcba_usb_get_free_ctx are executed by different
 * threads. The order of execution in below function is important.
 */
static inline void mcba_usb_free_ctx(struct mcba_usb_ctx *ctx)
{
<------>/* Increase number of free ctxs before freeing ctx */
<------>atomic_inc(&ctx->priv->free_ctx_cnt);
 
<------>ctx->ndx = MCBA_CTX_FREE;
 
<------>/* Wake up the queue once ctx is marked free */
<------>netif_wake_queue(ctx->priv->netdev);
}
 
static void mcba_usb_write_bulk_callback(struct urb *urb)
{
<------>struct mcba_usb_ctx *ctx = urb->context;
<------>struct net_device *netdev;
 
<------>WARN_ON(!ctx);
 
<------>netdev = ctx->priv->netdev;
 
<------>/* free up our allocated buffer */
<------>usb_free_coherent(urb->dev, urb->transfer_buffer_length,
<------><------><------>  urb->transfer_buffer, urb->transfer_dma);
 
<------>if (ctx->can) {
<------><------>if (!netif_device_present(netdev))
<------><------><------>return;
 
<------><------>netdev->stats.tx_packets++;
<------><------>netdev->stats.tx_bytes += ctx->dlc;
 
<------><------>can_led_event(netdev, CAN_LED_EVENT_TX);
<------><------>can_get_echo_skb(netdev, ctx->ndx);
<------>}
 
<------>if (urb->status)
<------><------>netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
 
<------>/* Release the context */
<------>mcba_usb_free_ctx(ctx);
}
 
/* Send data to device */
static netdev_tx_t mcba_usb_xmit(struct mcba_priv *priv,
<------><------><------><------> struct mcba_usb_msg *usb_msg,
<------><------><------><------> struct mcba_usb_ctx *ctx)
{
<------>struct urb *urb;
<------>u8 *buf;
<------>int err;
 
<------>/* create a URB, and a buffer for it, and copy the data to the URB */
<------>urb = usb_alloc_urb(0, GFP_ATOMIC);
<------>if (!urb)
<------><------>return -ENOMEM;
 
<------>buf = usb_alloc_coherent(priv->udev, MCBA_USB_TX_BUFF_SIZE, GFP_ATOMIC,
<------><------><------><------> &urb->transfer_dma);
<------>if (!buf) {
<------><------>err = -ENOMEM;
<------><------>goto nomembuf;
<------>}
 
<------>memcpy(buf, usb_msg, MCBA_USB_TX_BUFF_SIZE);
 
<------>usb_fill_bulk_urb(urb, priv->udev, priv->tx_pipe, buf, MCBA_USB_TX_BUFF_SIZE,
<------><------><------>  mcba_usb_write_bulk_callback, ctx);
 
<------>urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
<------>usb_anchor_urb(urb, &priv->tx_submitted);
 
<------>err = usb_submit_urb(urb, GFP_ATOMIC);
<------>if (unlikely(err))
<------><------>goto failed;
 
<------>/* Release our reference to this URB, the USB core will eventually free
<------> * it entirely.
<------> */
<------>usb_free_urb(urb);
 
<------>return 0;
 
failed:
<------>usb_unanchor_urb(urb);
<------>usb_free_coherent(priv->udev, MCBA_USB_TX_BUFF_SIZE, buf,
<------><------><------>  urb->transfer_dma);
 
<------>if (err == -ENODEV)
<------><------>netif_device_detach(priv->netdev);
<------>else
<------><------>netdev_warn(priv->netdev, "failed tx_urb %d\n", err);
 
nomembuf:
<------>usb_free_urb(urb);
 
<------>return err;
}
 
/* Send data to device */
static netdev_tx_t mcba_usb_start_xmit(struct sk_buff *skb,
<------><------><------><------>       struct net_device *netdev)
{
<------>struct mcba_priv *priv = netdev_priv(netdev);
<------>struct can_frame *cf = (struct can_frame *)skb->data;
<------>struct mcba_usb_ctx *ctx = NULL;
<------>struct net_device_stats *stats = &priv->netdev->stats;
<------>u16 sid;
<------>int err;
<------>struct mcba_usb_msg_can usb_msg = {
<------><------>.cmd_id = MBCA_CMD_TRANSMIT_MESSAGE_EV
<------>};
 
<------>if (can_dropped_invalid_skb(netdev, skb))
<------><------>return NETDEV_TX_OK;
 
<------>ctx = mcba_usb_get_free_ctx(priv, cf);
<------>if (!ctx)
<------><------>return NETDEV_TX_BUSY;
 
<------>if (cf->can_id & CAN_EFF_FLAG) {
<------><------>/* SIDH    | SIDL                 | EIDH   | EIDL
<------><------> * 28 - 21 | 20 19 18 x x x 17 16 | 15 - 8 | 7 - 0
<------><------> */
<------><------>sid = MCBA_SIDL_EXID_MASK;
<------><------>/* store 28-18 bits */
<------><------>sid |= (cf->can_id & 0x1ffc0000) >> 13;
<------><------>/* store 17-16 bits */
<------><------>sid |= (cf->can_id & 0x30000) >> 16;
<------><------>put_unaligned_be16(sid, &usb_msg.sid);
 
<------><------>/* store 15-0 bits */
<------><------>put_unaligned_be16(cf->can_id & 0xffff, &usb_msg.eid);
<------>} else {
<------><------>/* SIDH   | SIDL
<------><------> * 10 - 3 | 2 1 0 x x x x x
<------><------> */
<------><------>put_unaligned_be16((cf->can_id & CAN_SFF_MASK) << 5,
<------><------><------><------>   &usb_msg.sid);
<------><------>usb_msg.eid = 0;
<------>}
 
<------>usb_msg.dlc = cf->can_dlc;
 
<------>memcpy(usb_msg.data, cf->data, usb_msg.dlc);
 
<------>if (cf->can_id & CAN_RTR_FLAG)
<------><------>usb_msg.dlc |= MCBA_DLC_RTR_MASK;
 
<------>can_put_echo_skb(skb, priv->netdev, ctx->ndx);
 
<------>err = mcba_usb_xmit(priv, (struct mcba_usb_msg *)&usb_msg, ctx);
<------>if (err)
<------><------>goto xmit_failed;
 
<------>return NETDEV_TX_OK;
 
xmit_failed:
<------>can_free_echo_skb(priv->netdev, ctx->ndx);
<------>mcba_usb_free_ctx(ctx);
<------>stats->tx_dropped++;
 
<------>return NETDEV_TX_OK;
}
 
/* Send cmd to device */
static void mcba_usb_xmit_cmd(struct mcba_priv *priv,
<------><------><------>      struct mcba_usb_msg *usb_msg)
{
<------>struct mcba_usb_ctx *ctx = NULL;
<------>int err;
 
<------>ctx = mcba_usb_get_free_ctx(priv, NULL);
<------>if (!ctx) {
<------><------>netdev_err(priv->netdev,
<------><------><------>   "Lack of free ctx. Sending (%d) cmd aborted",
<------><------><------>   usb_msg->cmd_id);
 
<------><------>return;
<------>}
 
<------>err = mcba_usb_xmit(priv, usb_msg, ctx);
<------>if (err)
<------><------>netdev_err(priv->netdev, "Failed to send cmd (%d)",
<------><------><------>   usb_msg->cmd_id);
}
 
static void mcba_usb_xmit_change_bitrate(struct mcba_priv *priv, u16 bitrate)
{
<------>struct mcba_usb_msg_change_bitrate usb_msg = {
<------><------>.cmd_id = MBCA_CMD_CHANGE_BIT_RATE
<------>};
 
<------>put_unaligned_be16(bitrate, &usb_msg.bitrate);
 
<------>mcba_usb_xmit_cmd(priv, (struct mcba_usb_msg *)&usb_msg);
}
 
static void mcba_usb_xmit_read_fw_ver(struct mcba_priv *priv, u8 pic)
{
<------>struct mcba_usb_msg_fw_ver usb_msg = {
<------><------>.cmd_id = MBCA_CMD_READ_FW_VERSION,
<------><------>.pic = pic
<------>};
 
<------>mcba_usb_xmit_cmd(priv, (struct mcba_usb_msg *)&usb_msg);
}
 
static void mcba_usb_process_can(struct mcba_priv *priv,
<------><------><------><------> struct mcba_usb_msg_can *msg)
{
<------>struct can_frame *cf;
<------>struct sk_buff *skb;
<------>struct net_device_stats *stats = &priv->netdev->stats;
<------>u16 sid;
 
<------>skb = alloc_can_skb(priv->netdev, &cf);
<------>if (!skb)
<------><------>return;
 
<------>sid = get_unaligned_be16(&msg->sid);
 
<------>if (sid & MCBA_SIDL_EXID_MASK) {
<------><------>/* SIDH    | SIDL                 | EIDH   | EIDL
<------><------> * 28 - 21 | 20 19 18 x x x 17 16 | 15 - 8 | 7 - 0
<------><------> */
<------><------>cf->can_id = CAN_EFF_FLAG;
 
<------><------>/* store 28-18 bits */
<------><------>cf->can_id |= (sid & 0xffe0) << 13;
<------><------>/* store 17-16 bits */
<------><------>cf->can_id |= (sid & 3) << 16;
<------><------>/* store 15-0 bits */
<------><------>cf->can_id |= get_unaligned_be16(&msg->eid);
<------>} else {
<------><------>/* SIDH   | SIDL
<------><------> * 10 - 3 | 2 1 0 x x x x x
<------><------> */
<------><------>cf->can_id = (sid & 0xffe0) >> 5;
<------>}
 
<------>if (msg->dlc & MCBA_DLC_RTR_MASK)
<------><------>cf->can_id |= CAN_RTR_FLAG;
 
<------>cf->can_dlc = get_can_dlc(msg->dlc & MCBA_DLC_MASK);
 
<------>memcpy(cf->data, msg->data, cf->can_dlc);
 
<------>stats->rx_packets++;
<------>stats->rx_bytes += cf->can_dlc;
 
<------>can_led_event(priv->netdev, CAN_LED_EVENT_RX);
<------>netif_rx(skb);
}
 
static void mcba_usb_process_ka_usb(struct mcba_priv *priv,
<------><------><------><------>    struct mcba_usb_msg_ka_usb *msg)
{
<------>if (unlikely(priv->usb_ka_first_pass)) {
<------><------>netdev_info(priv->netdev, "PIC USB version %hhu.%hhu\n",
<------><------><------>    msg->soft_ver_major, msg->soft_ver_minor);
 
<------><------>priv->usb_ka_first_pass = false;
<------>}
 
<------>if (msg->termination_state)
<------><------>priv->can.termination = MCBA_TERMINATION_ENABLED;
<------>else
<------><------>priv->can.termination = MCBA_TERMINATION_DISABLED;
}
 
static u32 convert_can2host_bitrate(struct mcba_usb_msg_ka_can *msg)
{
<------>const u32 bitrate = get_unaligned_be16(&msg->can_bitrate);
 
<------>if ((bitrate == 33) || (bitrate == 83))
<------><------>return bitrate * 1000 + 333;
<------>else
<------><------>return bitrate * 1000;
}
 
static void mcba_usb_process_ka_can(struct mcba_priv *priv,
<------><------><------><------>    struct mcba_usb_msg_ka_can *msg)
{
<------>if (unlikely(priv->can_ka_first_pass)) {
<------><------>netdev_info(priv->netdev, "PIC CAN version %hhu.%hhu\n",
<------><------><------>    msg->soft_ver_major, msg->soft_ver_minor);
 
<------><------>priv->can_ka_first_pass = false;
<------>}
 
<------>if (unlikely(priv->can_speed_check)) {
<------><------>const u32 bitrate = convert_can2host_bitrate(msg);
 
<------><------>priv->can_speed_check = false;
 
<------><------>if (bitrate != priv->can.bittiming.bitrate)
<------><------><------>netdev_err(
<------><------><------>    priv->netdev,
<------><------><------>    "Wrong bitrate reported by the device (%u). Expected %u",
<------><------><------>    bitrate, priv->can.bittiming.bitrate);
<------>}
 
<------>priv->bec.txerr = msg->tx_err_cnt;
<------>priv->bec.rxerr = msg->rx_err_cnt;
 
<------>if (msg->tx_bus_off)
<------><------>priv->can.state = CAN_STATE_BUS_OFF;
 
<------>else if ((priv->bec.txerr > MCBA_CAN_STATE_ERR_PSV_TH) ||
<------><------> (priv->bec.rxerr > MCBA_CAN_STATE_ERR_PSV_TH))
<------><------>priv->can.state = CAN_STATE_ERROR_PASSIVE;
 
<------>else if ((priv->bec.txerr > MCBA_CAN_STATE_WRN_TH) ||
<------><------> (priv->bec.rxerr > MCBA_CAN_STATE_WRN_TH))
<------><------>priv->can.state = CAN_STATE_ERROR_WARNING;
}
 
static void mcba_usb_process_rx(struct mcba_priv *priv,
<------><------><------><------>struct mcba_usb_msg *msg)
{
<------>switch (msg->cmd_id) {
<------>case MBCA_CMD_I_AM_ALIVE_FROM_CAN:
<------><------>mcba_usb_process_ka_can(priv,
<------><------><------><------><------>(struct mcba_usb_msg_ka_can *)msg);
<------><------>break;
 
<------>case MBCA_CMD_I_AM_ALIVE_FROM_USB:
<------><------>mcba_usb_process_ka_usb(priv,
<------><------><------><------><------>(struct mcba_usb_msg_ka_usb *)msg);
<------><------>break;
 
<------>case MBCA_CMD_RECEIVE_MESSAGE:
<------><------>mcba_usb_process_can(priv, (struct mcba_usb_msg_can *)msg);
<------><------>break;
 
<------>case MBCA_CMD_NOTHING_TO_SEND:
<------><------>/* Side effect of communication between PIC_USB and PIC_CAN.
<------><------> * PIC_CAN is telling us that it has nothing to send
<------><------> */
<------><------>break;
 
<------>case MBCA_CMD_TRANSMIT_MESSAGE_RSP:
<------><------>/* Transmission response from the device containing timestamp */
<------><------>break;
 
<------>default:
<------><------>netdev_warn(priv->netdev, "Unsupported msg (0x%hhX)",
<------><------><------>    msg->cmd_id);
<------><------>break;
<------>}
}
 
/* Callback for reading data from device
 *
 * Check urb status, call read function and resubmit urb read operation.
 */
static void mcba_usb_read_bulk_callback(struct urb *urb)
{
<------>struct mcba_priv *priv = urb->context;
<------>struct net_device *netdev;
<------>int retval;
<------>int pos = 0;
 
<------>netdev = priv->netdev;
 
<------>if (!netif_device_present(netdev))
<------><------>return;
 
<------>switch (urb->status) {
<------>case 0: /* success */
<------><------>break;
 
<------>case -ENOENT:
<------>case -EPIPE:
<------>case -EPROTO:
<------>case -ESHUTDOWN:
<------><------>return;
 
<------>default:
<------><------>netdev_info(netdev, "Rx URB aborted (%d)\n", urb->status);
 
<------><------>goto resubmit_urb;
<------>}
 
<------>while (pos < urb->actual_length) {
<------><------>struct mcba_usb_msg *msg;
 
<------><------>if (pos + sizeof(struct mcba_usb_msg) > urb->actual_length) {
<------><------><------>netdev_err(priv->netdev, "format error\n");
<------><------><------>break;
<------><------>}
 
<------><------>msg = (struct mcba_usb_msg *)(urb->transfer_buffer + pos);
<------><------>mcba_usb_process_rx(priv, msg);
 
<------><------>pos += sizeof(struct mcba_usb_msg);
<------>}
 
resubmit_urb:
 
<------>usb_fill_bulk_urb(urb, priv->udev,
<------><------><------>  priv->rx_pipe,
<------><------><------>  urb->transfer_buffer, MCBA_USB_RX_BUFF_SIZE,
<------><------><------>  mcba_usb_read_bulk_callback, priv);
 
<------>retval = usb_submit_urb(urb, GFP_ATOMIC);
 
<------>if (retval == -ENODEV)
<------><------>netif_device_detach(netdev);
<------>else if (retval)
<------><------>netdev_err(netdev, "failed resubmitting read bulk urb: %d\n",
<------><------><------>   retval);
}
 
/* Start USB device */
static int mcba_usb_start(struct mcba_priv *priv)
{
<------>struct net_device *netdev = priv->netdev;
<------>int err, i;
 
<------>mcba_init_ctx(priv);
 
<------>for (i = 0; i < MCBA_MAX_RX_URBS; i++) {
<------><------>struct urb *urb = NULL;
<------><------>u8 *buf;
<------><------>dma_addr_t buf_dma;
 
<------><------>/* create a URB, and a buffer for it */
<------><------>urb = usb_alloc_urb(0, GFP_KERNEL);
<------><------>if (!urb) {
<------><------><------>err = -ENOMEM;
<------><------><------>break;
<------><------>}
 
<------><------>buf = usb_alloc_coherent(priv->udev, MCBA_USB_RX_BUFF_SIZE,
<------><------><------><------><------> GFP_KERNEL, &buf_dma);
<------><------>if (!buf) {
<------><------><------>netdev_err(netdev, "No memory left for USB buffer\n");
<------><------><------>usb_free_urb(urb);
<------><------><------>err = -ENOMEM;
<------><------><------>break;
<------><------>}
 
<------><------>urb->transfer_dma = buf_dma;
 
<------><------>usb_fill_bulk_urb(urb, priv->udev,
<------><------><------><------>  priv->rx_pipe,
<------><------><------><------>  buf, MCBA_USB_RX_BUFF_SIZE,
<------><------><------><------>  mcba_usb_read_bulk_callback, priv);
<------><------>urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
<------><------>usb_anchor_urb(urb, &priv->rx_submitted);
 
<------><------>err = usb_submit_urb(urb, GFP_KERNEL);
<------><------>if (err) {
<------><------><------>usb_unanchor_urb(urb);
<------><------><------>usb_free_coherent(priv->udev, MCBA_USB_RX_BUFF_SIZE,
<------><------><------><------><------>  buf, buf_dma);
<------><------><------>usb_free_urb(urb);
<------><------><------>break;
<------><------>}
 
<------><------>priv->rxbuf[i] = buf;
<------><------>priv->rxbuf_dma[i] = buf_dma;
 
<------><------>/* Drop reference, USB core will take care of freeing it */
<------><------>usb_free_urb(urb);
<------>}
 
<------>/* Did we submit any URBs */
<------>if (i == 0) {
<------><------>netdev_warn(netdev, "couldn't setup read URBs\n");
<------><------>return err;
<------>}
 
<------>/* Warn if we've couldn't transmit all the URBs */
<------>if (i < MCBA_MAX_RX_URBS)
<------><------>netdev_warn(netdev, "rx performance may be slow\n");
 
<------>mcba_usb_xmit_read_fw_ver(priv, MCBA_VER_REQ_USB);
<------>mcba_usb_xmit_read_fw_ver(priv, MCBA_VER_REQ_CAN);
 
<------>return err;
}
 
/* Open USB device */
static int mcba_usb_open(struct net_device *netdev)
{
<------>struct mcba_priv *priv = netdev_priv(netdev);
<------>int err;
 
<------>/* common open */
<------>err = open_candev(netdev);
<------>if (err)
<------><------>return err;
 
<------>priv->can_speed_check = true;
<------>priv->can.state = CAN_STATE_ERROR_ACTIVE;
 
<------>can_led_event(netdev, CAN_LED_EVENT_OPEN);
<------>netif_start_queue(netdev);
 
<------>return 0;
}
 
static void mcba_urb_unlink(struct mcba_priv *priv)
{
<------>int i;
 
<------>usb_kill_anchored_urbs(&priv->rx_submitted);
 
<------>for (i = 0; i < MCBA_MAX_RX_URBS; ++i)
<------><------>usb_free_coherent(priv->udev, MCBA_USB_RX_BUFF_SIZE,
<------><------><------><------>  priv->rxbuf[i], priv->rxbuf_dma[i]);
 
<------>usb_kill_anchored_urbs(&priv->tx_submitted);
}
 
/* Close USB device */
static int mcba_usb_close(struct net_device *netdev)
{
<------>struct mcba_priv *priv = netdev_priv(netdev);
 
<------>priv->can.state = CAN_STATE_STOPPED;
 
<------>netif_stop_queue(netdev);
 
<------>/* Stop polling */
<------>mcba_urb_unlink(priv);
 
<------>close_candev(netdev);
<------>can_led_event(netdev, CAN_LED_EVENT_STOP);
 
<------>return 0;
}
 
/* Set network device mode
 *
 * Maybe we should leave this function empty, because the device
 * set mode variable with open command.
 */
static int mcba_net_set_mode(struct net_device *netdev, enum can_mode mode)
{
<------>return 0;
}
 
static int mcba_net_get_berr_counter(const struct net_device *netdev,
<------><------><------><------>     struct can_berr_counter *bec)
{
<------>struct mcba_priv *priv = netdev_priv(netdev);
 
<------>bec->txerr = priv->bec.txerr;
<------>bec->rxerr = priv->bec.rxerr;
 
<------>return 0;
}
 
static const struct net_device_ops mcba_netdev_ops = {
<------>.ndo_open = mcba_usb_open,
<------>.ndo_stop = mcba_usb_close,
<------>.ndo_start_xmit = mcba_usb_start_xmit,
};
 
/* Microchip CANBUS has hardcoded bittiming values by default.
 * This function sends request via USB to change the speed and align bittiming
 * values for presentation purposes only
 */
static int mcba_net_set_bittiming(struct net_device *netdev)
{
<------>struct mcba_priv *priv = netdev_priv(netdev);
<------>const u16 bitrate_kbps = priv->can.bittiming.bitrate / 1000;
 
<------>mcba_usb_xmit_change_bitrate(priv, bitrate_kbps);
 
<------>return 0;
}
 
static int mcba_set_termination(struct net_device *netdev, u16 term)
{
<------>struct mcba_priv *priv = netdev_priv(netdev);
<------>struct mcba_usb_msg_termination usb_msg = {
<------><------>.cmd_id = MBCA_CMD_SETUP_TERMINATION_RESISTANCE
<------>};
 
<------>if (term == MCBA_TERMINATION_ENABLED)
<------><------>usb_msg.termination = 1;
<------>else
<------><------>usb_msg.termination = 0;
 
<------>mcba_usb_xmit_cmd(priv, (struct mcba_usb_msg *)&usb_msg);
 
<------>return 0;
}
 
static int mcba_usb_probe(struct usb_interface *intf,
<------><------><------>  const struct usb_device_id *id)
{
<------>struct net_device *netdev;
<------>struct mcba_priv *priv;
<------>int err;
<------>struct usb_device *usbdev = interface_to_usbdev(intf);
<------>struct usb_endpoint_descriptor *in, *out;
 
<------>err = usb_find_common_endpoints(intf->cur_altsetting, &in, &out, NULL, NULL);
<------>if (err) {
<------><------>dev_err(&intf->dev, "Can't find endpoints\n");
<------><------>return err;
<------>}
 
<------>netdev = alloc_candev(sizeof(struct mcba_priv), MCBA_MAX_TX_URBS);
<------>if (!netdev) {
<------><------>dev_err(&intf->dev, "Couldn't alloc candev\n");
<------><------>return -ENOMEM;
<------>}
 
<------>priv = netdev_priv(netdev);
 
<------>priv->udev = usbdev;
<------>priv->netdev = netdev;
<------>priv->usb_ka_first_pass = true;
<------>priv->can_ka_first_pass = true;
<------>priv->can_speed_check = false;
 
<------>init_usb_anchor(&priv->rx_submitted);
<------>init_usb_anchor(&priv->tx_submitted);
 
<------>usb_set_intfdata(intf, priv);
 
<------>/* Init CAN device */
<------>priv->can.state = CAN_STATE_STOPPED;
<------>priv->can.termination_const = mcba_termination;
<------>priv->can.termination_const_cnt = ARRAY_SIZE(mcba_termination);
<------>priv->can.bitrate_const = mcba_bitrate;
<------>priv->can.bitrate_const_cnt = ARRAY_SIZE(mcba_bitrate);
 
<------>priv->can.do_set_termination = mcba_set_termination;
<------>priv->can.do_set_mode = mcba_net_set_mode;
<------>priv->can.do_get_berr_counter = mcba_net_get_berr_counter;
<------>priv->can.do_set_bittiming = mcba_net_set_bittiming;
 
<------>netdev->netdev_ops = &mcba_netdev_ops;
 
<------>netdev->flags |= IFF_ECHO; /* we support local echo */
 
<------>SET_NETDEV_DEV(netdev, &intf->dev);
 
<------>err = register_candev(netdev);
<------>if (err) {
<------><------>netdev_err(netdev, "couldn't register CAN device: %d\n", err);
 
<------><------>goto cleanup_free_candev;
<------>}
 
<------>priv->rx_pipe = usb_rcvbulkpipe(priv->udev, in->bEndpointAddress);
<------>priv->tx_pipe = usb_sndbulkpipe(priv->udev, out->bEndpointAddress);
 
<------>devm_can_led_init(netdev);
 
<------>/* Start USB dev only if we have successfully registered CAN device */
<------>err = mcba_usb_start(priv);
<------>if (err) {
<------><------>if (err == -ENODEV)
<------><------><------>netif_device_detach(priv->netdev);
 
<------><------>netdev_warn(netdev, "couldn't start device: %d\n", err);
 
<------><------>goto cleanup_unregister_candev;
<------>}
 
<------>dev_info(&intf->dev, "Microchip CAN BUS Analyzer connected\n");
 
<------>return 0;
 
cleanup_unregister_candev:
<------>unregister_candev(priv->netdev);
 
cleanup_free_candev:
<------>free_candev(netdev);
 
<------>return err;
}
 
/* Called by the usb core when driver is unloaded or device is removed */
static void mcba_usb_disconnect(struct usb_interface *intf)
{
<------>struct mcba_priv *priv = usb_get_intfdata(intf);
 
<------>usb_set_intfdata(intf, NULL);
 
<------>netdev_info(priv->netdev, "device disconnected\n");
 
<------>unregister_candev(priv->netdev);
<------>mcba_urb_unlink(priv);
<------>free_candev(priv->netdev);
}
 
static struct usb_driver mcba_usb_driver = {
<------>.name = MCBA_MODULE_NAME,
<------>.probe = mcba_usb_probe,
<------>.disconnect = mcba_usb_disconnect,
<------>.id_table = mcba_usb_table,
};
 
module_usb_driver(mcba_usb_driver);
 
MODULE_AUTHOR("Remigiusz Kołłątaj <remigiusz.kollataj@mobica.com>");
MODULE_DESCRIPTION("SocketCAN driver for Microchip CAN BUS Analyzer Tool");
MODULE_LICENSE("GPL v2");