/* This performs a two-way transfer over AXI DMA, both sending data out and
* receiving it back over DMA. The user determines if this call is blocking. */
int axidma_twoway_transfer(axidma_dev_t dev, int tx_channel, void *tx_buf,
size_t tx_len, int rx_channel, void *rx_buf, size_t rx_len, bool wait)
{
int rc;
struct axidma_inout_transaction trans;
assert(valid_channel(dev, tx_channel, AXIDMA_WRITE));
assert(valid_channel(dev, rx_channel, AXIDMA_READ));
// Setup the argument structure for the IOCTL
trans.wait = wait;
trans.tx_channel_id = tx_channel;
trans.tx_buf = tx_buf;
trans.tx_buf_len = tx_len;
trans.rx_channel_id = rx_channel;
trans.rx_buf = rx_buf;
trans.rx_buf_len = rx_len;
// Perform the read-write transfer
rc = ioctl(dev->fd, AXIDMA_DMA_READWRITE, &trans);
if (rc < 0) {
perror("Failed to perform the AXI DMA read-write transfer");
}
return rc;
}
/* This performs a one-way transfer over AXI DMA, the direction being specified
* by the user. The user determines if this is blocking or not with `wait. */
int axidma_oneway_transfer(axidma_dev_t dev, enum axidma_dir dir, int channel,
void *buf, size_t len, bool wait)
{
int rc;
struct axidma_transaction trans;
unsigned long axidma_cmd;
assert(dir == AXIDMA_READ || dir == AXIDMA_WRITE);
assert(dir != AXIDMA_READ || valid_channel(dev, channel, AXIDMA_READ));
assert(dir != AXIDMA_WRITE || valid_channel(dev, channel, AXIDMA_WRITE));
// Setup the argument structure to the IOCTL
trans.wait = wait;
trans.channel_id = channel;
trans.buf = buf;
trans.buf_len = len;
axidma_cmd = dir_to_ioctl(dir);
// Perform the given transfer
rc = ioctl(dev->fd, axidma_cmd, &trans);
if (rc < 0) {
perror("Failed to perform the AXI DMA transfer");
return rc;
}
return 0;
}
/*
send a buffer out a MAVLink channel
*/
void comm_send_buffer(mavlink_channel_t chan, const uint8_t *buf, uint8_t len)
{
if (!valid_channel(chan)) {
return;
}
mavlink_comm_port[chan]->write(buf, len);
}
/// Read a byte from the nominated MAVLink channel
///
/// @param chan Channel to receive on
/// @returns Byte read
///
uint8_t comm_receive_ch(mavlink_channel_t chan)
{
if (!valid_channel(chan)) {
return 0;
}
return (uint8_t)mavlink_comm_port[chan]->read();
}
/*
lock a channel, preventing use by MAVLink
*/
void GCS_MAVLINK::lock_channel(mavlink_channel_t _chan, bool lock)
{
if (!valid_channel(chan)) {
return;
}
if (lock) {
mavlink_locked_mask |= (1U<<(unsigned)_chan);
} else {
mavlink_locked_mask &= ~(1U<<(unsigned)_chan);
}
}
/* This function stops all transfers on the given channel with the given
* direction. This function is required to stop any video transfers, or any
* non-blocking transfers. */
void axidma_stop_transfer(axidma_dev_t dev, int channel, enum axidma_dir dir)
{
struct axidma_chan chan;
assert(dir == AXIDMA_READ || dir == AXIDMA_WRITE);
assert(dir != AXIDMA_READ || valid_channel(dev, channel, AXIDMA_READ));
assert(dir != AXIDMA_WRITE || valid_channel(dev, channel, AXIDMA_WRITE));
// Setup the argument structure for the IOCTL
chan.channel_id = channel;
chan.dir = dir;
chan.type = AXIDMA_DMA;
// Stop all transfers on the given DMA channel
if (ioctl(dev->fd, AXIDMA_STOP_DMA_CHANNEL, &chan) < 0) {
perror("Failed to stop the DMA channel");
assert(false);
}
return;
}
/// Check for available data on the nominated MAVLink channel
///
/// @param chan Channel to check
/// @returns Number of bytes available
uint16_t comm_get_available(mavlink_channel_t chan)
{
if (!valid_channel(chan)) {
return 0;
}
if ((1U<<chan) & mavlink_locked_mask) {
return 0;
}
int16_t bytes = mavlink_comm_port[chan]->available();
if (bytes == -1) {
return 0;
}
return (uint16_t)bytes;
}
/// Check for available transmit space on the nominated MAVLink channel
///
/// @param chan Channel to check
/// @returns Number of bytes available
uint16_t comm_get_txspace(mavlink_channel_t chan)
{
if (!valid_channel(chan)) {
return 0;
}
if ((1U<<chan) & mavlink_locked_mask) {
return 0;
}
int16_t ret = mavlink_comm_port[chan]->txspace();
if (ret < 0) {
ret = 0;
}
return (uint16_t)ret;
}
void
GCS_MAVLINK::init(AP_HAL::UARTDriver *port, mavlink_channel_t mav_chan)
{
if (!valid_channel(mav_chan)) {
return;
}
_port = port;
chan = mav_chan;
mavlink_comm_port[chan] = _port;
initialised = true;
_queued_parameter = NULL;
reset_cli_timeout();
}
/*
return true if a channel has flow control
*/
bool GCS_MAVLINK::have_flow_control(void)
{
if (!valid_channel(chan)) {
return false;
}
if (mavlink_comm_port[chan] == NULL) {
return false;
}
if (chan == MAVLINK_COMM_0) {
// assume USB console has flow control
return hal.gpio->usb_connected() || mavlink_comm_port[chan]->get_flow_control() != AP_HAL::UARTDriver::FLOW_CONTROL_DISABLE;
} else {
// all other channels
return mavlink_comm_port[chan]->get_flow_control() != AP_HAL::UARTDriver::FLOW_CONTROL_DISABLE;
}
}
/* This function performs a video transfer over AXI DMA, setting up the DMA to
* read from the given frame buffers on-demand continuously. This call is
* always non-blocking. The transfer must be stopped with a call to
* axidma_stop_transfer. */
int axidma_video_transfer(axidma_dev_t dev, int display_channel, size_t width,
size_t height, size_t depth, void **frame_buffers, int num_buffers)
{
int rc;
struct axidma_video_transaction trans;
assert(valid_channel(dev, display_channel, AXIDMA_WRITE));
// Setup the argument structure for the IOCTL
trans.channel_id = display_channel;
trans.num_frame_buffers = num_buffers;
trans.frame_buffers = frame_buffers;
trans.width = width;
trans.height = height;
trans.depth = depth;
// Perform the video transfer
rc = ioctl(dev->fd, AXIDMA_DMA_VIDEO_WRITE, &trans);
if (rc < 0) {
perror("Failed to perform the AXI DMA video write transfer");
}
return rc;
}