Function rt_can_open

components/drivers/can/dev_can.c:392–503

* @internal * @brief Opens the CAN device and initializes its resources. * * This function is called when `rt_device_open()` is invoked on a CAN device. * It allocates and initializes software FIFOs for reception and transmission, * sets up semaphores for the blocking send mechanism, configures the non-blocking * send buffer, and starts the periodic status timer. * * @param[in] dev A poi

 * @return `RT_EOK` on successful opening, or an error code on failure.
 */
static rt_err_t rt_can_open(struct rt_device *dev, rt_uint16_t oflag)
{
    struct rt_can_device *can;
    char tmpname[16];
    RT_ASSERT(dev != RT_NULL);
    can = (struct rt_can_device *)dev;

    CAN_LOCK(can);

    /* get open flags */
    dev->open_flag = oflag & 0xff;
    if (can->can_rx == RT_NULL)
    {
        if (oflag & RT_DEVICE_FLAG_INT_RX)
        {
            int i = 0;
            struct rt_can_rx_fifo *rx_fifo;

            rx_fifo = (struct rt_can_rx_fifo *) rt_malloc(sizeof(struct rt_can_rx_fifo) +
                      can->config.msgboxsz * sizeof(struct rt_can_msg_list));
            RT_ASSERT(rx_fifo != RT_NULL);

            rx_fifo->buffer = (struct rt_can_msg_list *)(rx_fifo + 1);
            rt_memset(rx_fifo->buffer, 0, can->config.msgboxsz * sizeof(struct rt_can_msg_list));
            rt_list_init(&rx_fifo->freelist);
            rt_list_init(&rx_fifo->uselist);
            rx_fifo->freenumbers = can->config.msgboxsz;
            for (i = 0;  i < can->config.msgboxsz; i++)
            {
                rt_list_insert_before(&rx_fifo->freelist, &rx_fifo->buffer[i].list);
#ifdef RT_CAN_USING_HDR
                rt_list_init(&rx_fifo->buffer[i].hdrlist);
                rx_fifo->buffer[i].owner = RT_NULL;
#endif
            }
            can->can_rx = rx_fifo;

            dev->open_flag |= RT_DEVICE_FLAG_INT_RX;
            /* open can rx interrupt */
            can->ops->control(can, RT_DEVICE_CTRL_SET_INT, (void *)RT_DEVICE_FLAG_INT_RX);
        }
    }

    if (can->can_tx == RT_NULL)
    {
        if (oflag & RT_DEVICE_FLAG_INT_TX)
        {
            int i = 0;
            struct rt_can_tx_fifo *tx_fifo;

            tx_fifo = (struct rt_can_tx_fifo *) rt_malloc(sizeof(struct rt_can_tx_fifo) +
                      can->config.sndboxnumber * sizeof(struct rt_can_sndbxinx_list));
            RT_ASSERT(tx_fifo != RT_NULL);

            tx_fifo->buffer = (struct rt_can_sndbxinx_list *)(tx_fifo + 1);
            rt_memset(tx_fifo->buffer, 0,
                    can->config.sndboxnumber * sizeof(struct rt_can_sndbxinx_list));
            rt_list_init(&tx_fifo->freelist);