void gnrc_lwmac_tx_stop(gnrc_netif_t *netif)
{
assert(netif != NULL);
gnrc_lwmac_clear_timeout(netif, GNRC_LWMAC_TIMEOUT_WR);
gnrc_lwmac_clear_timeout(netif, GNRC_LWMAC_TIMEOUT_NO_RESPONSE);
gnrc_lwmac_clear_timeout(netif, GNRC_LWMAC_TIMEOUT_NEXT_BROADCAST);
gnrc_lwmac_clear_timeout(netif, GNRC_LWMAC_TIMEOUT_BROADCAST_END);
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_STOPPED;
/* Release packet in case of failure */
if (netif->mac.tx.packet) {
if (netif->mac.tx.tx_retry_count >= GNRC_LWMAC_MAX_DATA_TX_RETRIES) {
netif->mac.tx.tx_retry_count = 0;
gnrc_pktbuf_release(netif->mac.tx.packet);
netif->mac.tx.packet = NULL;
LOG_WARNING("WARNING: [LWMAC-tx] Drop TX packet\n");
}
else {
netif->mac.tx.tx_retry_count++;
return;
}
}
if (!gnrc_lwmac_get_tx_continue(netif)) {
netif->mac.tx.current_neighbor = NULL;
}
}
static void _tx_management_success(gnrc_netif_t *netif)
{
if (netif->mac.tx.current_neighbor == &(netif->mac.tx.neighbors[0])) {
LOG_INFO("[LWMAC] Broadcast transmission done\n");
}
gnrc_lwmac_tx_stop(netif);
/* In case have pending packets for the same receiver, continue to
* send immediately, before the maximum transmit-limit */
if ((gnrc_lwmac_get_tx_continue(netif)) &&
(netif->mac.tx.tx_burst_count < GNRC_LWMAC_MAX_TX_BURST_PKT_NUM)) {
lwmac_schedule_update(netif);
}
else {
lwmac_set_state(netif, GNRC_LWMAC_SLEEPING);
}
}
/* Returns whether rescheduling is needed or not */
static bool _lwmac_tx_update(gnrc_netif_t *netif)
{
assert(netif != NULL);
bool reschedule = false;
switch (netif->mac.tx.state) {
case GNRC_LWMAC_TX_STATE_INIT: {
gnrc_lwmac_clear_timeout(netif, GNRC_LWMAC_TIMEOUT_WR);
gnrc_lwmac_clear_timeout(netif, GNRC_LWMAC_TIMEOUT_NO_RESPONSE);
gnrc_lwmac_clear_timeout(netif, GNRC_LWMAC_TIMEOUT_NEXT_BROADCAST);
gnrc_lwmac_clear_timeout(netif, GNRC_LWMAC_TIMEOUT_BROADCAST_END);
/* if found ongoing transmission,
* quit this cycle for collision avoidance. */
if (_gnrc_lwmac_get_netdev_state(netif) == NETOPT_STATE_RX) {
if (!gnrc_mac_queue_tx_packet(&netif->mac.tx, 0, netif->mac.tx.packet)) {
gnrc_pktbuf_release(netif->mac.tx.packet);
LOG_WARNING("WARNING: [LWMAC-tx] TX queue full, drop packet\n");
}
/* drop pointer so it wont be free'd */
netif->mac.tx.packet = NULL;
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
/* check if the packet is for broadcast */
if (gnrc_netif_hdr_get_flag(netif->mac.tx.packet) &
(GNRC_NETIF_HDR_FLAGS_BROADCAST | GNRC_NETIF_HDR_FLAGS_MULTICAST)) {
/* Set CSMA retries as configured and enable */
uint8_t csma_retries = GNRC_LWMAC_BROADCAST_CSMA_RETRIES;
netif->dev->driver->set(netif->dev, NETOPT_CSMA_RETRIES,
&csma_retries, sizeof(csma_retries));
netif->mac.mac_info |= GNRC_NETIF_MAC_INFO_CSMA_ENABLED;
netopt_enable_t csma_enable = NETOPT_ENABLE;
netif->dev->driver->set(netif->dev, NETOPT_CSMA,
&csma_enable, sizeof(csma_enable));
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_SEND_BROADCAST;
reschedule = true;
break;
}
else {
/* Use CSMA for the first WR */
netif->mac.mac_info |= GNRC_NETIF_MAC_INFO_CSMA_ENABLED;
netopt_enable_t csma_disable = NETOPT_ENABLE;
netif->dev->driver->set(netif->dev, NETOPT_CSMA,
&csma_disable, sizeof(csma_disable));
/* Set a timeout for the maximum transmission procedure */
gnrc_lwmac_set_timeout(netif, GNRC_LWMAC_TIMEOUT_NO_RESPONSE, GNRC_LWMAC_PREAMBLE_DURATION_US);
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_SEND_WR;
reschedule = true;
break;
}
}
case GNRC_LWMAC_TX_STATE_SEND_BROADCAST: {
uint8_t tx_info = _send_bcast(netif);
if (tx_info & GNRC_LWMAC_TX_SUCCESS) {
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_SUCCESSFUL;
reschedule = true;
break;
}
if (tx_info & GNRC_LWMAC_TX_FAIL) {
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
break;
}
case GNRC_LWMAC_TX_STATE_SEND_WR: {
/* In case of no Tx-isr error (e.g., no Tx-isr), goto TX failure. */
if (gnrc_lwmac_timeout_is_expired(netif, GNRC_LWMAC_TIMEOUT_NO_RESPONSE)) {
LOG_WARNING("WARNING: [LWMAC-tx] No response from destination, "
"probably no TX-ISR\n");
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
LOG_DEBUG("[LWMAC-tx] GNRC_LWMAC_TX_STATE_SEND_WR\n");
uint8_t tx_info = _send_wr(netif);
if (tx_info & GNRC_LWMAC_TX_FAIL) {
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_WAIT_WR_SENT;
reschedule = false;
break;
}
case GNRC_LWMAC_TX_STATE_WAIT_WR_SENT: {
LOG_DEBUG("[LWMAC-tx] GNRC_LWMAC_TX_STATE_WAIT_WR_SENT\n");
/* In case of no Tx-isr error (e.g., no Tx-isr), goto TX failure. */
if (gnrc_lwmac_timeout_is_expired(netif, GNRC_LWMAC_TIMEOUT_NO_RESPONSE)) {
LOG_WARNING("WARNING: [LWMAC-tx] No response from destination\n");
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
if (gnrc_netif_get_tx_feedback(netif) == TX_FEEDBACK_UNDEF) {
LOG_DEBUG("[LWMAC-tx] WR not yet completely sent\n");
break;
}
/* If found ongoing transmission, goto TX failure, i.e., postpone transmission to
* next cycle. This is mainly for collision avoidance. */
if (gnrc_netif_get_tx_feedback(netif) == TX_FEEDBACK_BUSY) {
if (!gnrc_mac_queue_tx_packet(&netif->mac.tx, 0, netif->mac.tx.packet)) {
gnrc_pktbuf_release(netif->mac.tx.packet);
LOG_WARNING("WARNING: [LWMAC-tx] TX queue full, drop packet\n");
}
/* clear packet point to avoid TX retry */
netif->mac.tx.packet = NULL;
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
if (netif->mac.tx.wr_sent == 0) {
/* Only the first WR use CSMA */
netif->mac.mac_info &= ~GNRC_NETIF_MAC_INFO_CSMA_ENABLED;
netopt_enable_t csma_disable = NETOPT_DISABLE;
netif->dev->driver->set(netif->dev, NETOPT_CSMA,
&csma_disable, sizeof(csma_disable));
}
netif->mac.tx.wr_sent++;
/* Set timeout for next WR in case no WA will be received */
gnrc_lwmac_set_timeout(netif, GNRC_LWMAC_TIMEOUT_WR, GNRC_LWMAC_TIME_BETWEEN_WR_US);
/* Debug WR timing */
LOG_DEBUG("[LWMAC-tx] Destination phase was: %" PRIu32 "\n",
netif->mac.tx.current_neighbor->phase);
LOG_DEBUG("[LWMAC-tx] Phase when sent was: %" PRIu32 "\n",
_gnrc_lwmac_ticks_to_phase(netif->mac.tx.timestamp));
LOG_DEBUG("[LWMAC-tx] Ticks when sent was: %" PRIu32 "\n",
netif->mac.tx.timestamp);
_gnrc_lwmac_set_netdev_state(netif, NETOPT_STATE_IDLE);
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_WAIT_FOR_WA;
reschedule = false;
break;
}
case GNRC_LWMAC_TX_STATE_WAIT_FOR_WA: {
LOG_DEBUG("[LWMAC-tx] GNRC_LWMAC_TX_STATE_WAIT_FOR_WA\n");
if (gnrc_lwmac_timeout_is_expired(netif, GNRC_LWMAC_TIMEOUT_NO_RESPONSE)) {
LOG_WARNING("WARNING: [LWMAC-tx] No response from destination\n");
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
if (gnrc_lwmac_timeout_is_expired(netif, GNRC_LWMAC_TIMEOUT_WR)) {
/* In case the sender is in consecutive (burst) transmission to the receiver,
* meaning that the sender has already successfully sent at least one data to
* the receiver, then the sender will only spend one WR for triggering the next
* transmission procedure. And, if this WR doesn't work (no WA replied), the
* sender regards consecutive transmission failed.
*/
if (gnrc_lwmac_get_tx_continue(netif)) {
LOG_DEBUG("[LWMAC-tx] Tx burst fail\n");
if (!gnrc_mac_queue_tx_packet(&netif->mac.tx, 0, netif->mac.tx.packet)) {
gnrc_pktbuf_release(netif->mac.tx.packet);
LOG_WARNING("WARNING: [LWMAC-tx] TX queue full, drop packet\n");
}
/* drop pointer so it wont be free'd */
netif->mac.tx.packet = NULL;
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
else {
/* If this is the first transmission to the receiver for locating the
* latter's wake-up period, the sender just keep sending WRs until it
* finds the WA.
*/
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_SEND_WR;
reschedule = true;
break;
}
}
if (_gnrc_lwmac_get_netdev_state(netif) == NETOPT_STATE_RX) {
/* Wait for completion of frame reception */
break;
}
uint8_t tx_info = _packet_process_in_wait_for_wa(netif);
if (tx_info & GNRC_LWMAC_TX_FAIL) {
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
if (tx_info & GNRC_LWMAC_TX_SUCCESS) {
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_SEND_DATA;
reschedule = true;
break;
}
else {
/* No WA yet */
break;
}
}
case GNRC_LWMAC_TX_STATE_SEND_DATA: {
LOG_DEBUG("[LWMAC-tx] GNRC_LWMAC_TX_STATE_SEND_DATA\n");
if (!_send_data(netif)) {
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_WAIT_FEEDBACK;
reschedule = false;
break;
}
case GNRC_LWMAC_TX_STATE_WAIT_FEEDBACK: {
/* In case of no Tx-isr error, goto TX failure. */
if (gnrc_lwmac_timeout_is_expired(netif, GNRC_LWMAC_TIMEOUT_NO_RESPONSE)) {
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
LOG_DEBUG("[LWMAC-tx] GNRC_LWMAC_TX_STATE_WAIT_FEEDBACK\n");
if (gnrc_netif_get_tx_feedback(netif) == TX_FEEDBACK_UNDEF) {
break;
}
else if (gnrc_netif_get_tx_feedback(netif) == TX_FEEDBACK_SUCCESS) {
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_SUCCESSFUL;
reschedule = true;
break;
}
else if (gnrc_netif_get_tx_feedback(netif) == TX_FEEDBACK_NOACK) {
LOG_ERROR("ERROR: [LWMAC-tx] Not ACKED\n");
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
else if (gnrc_netif_get_tx_feedback(netif) == TX_FEEDBACK_BUSY) {
LOG_ERROR("ERROR: [LWMAC-tx] Channel busy \n");
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
LOG_ERROR("ERROR: [LWMAC-tx] Tx feedback unhandled: %i\n",
gnrc_netif_get_tx_feedback(netif));
netif->mac.tx.state = GNRC_LWMAC_TX_STATE_FAILED;
reschedule = true;
break;
}
case GNRC_LWMAC_TX_STATE_SUCCESSFUL:
case GNRC_LWMAC_TX_STATE_FAILED: {
break;
}
case GNRC_LWMAC_TX_STATE_STOPPED: {
LOG_DEBUG("[LWMAC-tx] Transmission state machine is stopped\n");
}
}
return reschedule;
}
