void nrf_drv_i2s_stop(void) { ASSERT(m_cb.state != NRF_DRV_STATE_UNINITIALIZED); // First disable interrupts, then trigger the STOP task, so no spurious // RXPTRUPD and TXPTRUPD events (see FTPAN-55) will be processed. nrf_i2s_int_disable(NRF_I2S, NRF_I2S_INT_RXPTRUPD_MASK | NRF_I2S_INT_TXPTRUPD_MASK); nrf_i2s_task_trigger(NRF_I2S, NRF_I2S_TASK_STOP); nrf_i2s_disable(NRF_I2S); m_cb.state = NRF_DRV_STATE_INITIALIZED; }
void nrfx_i2s_irq_handler(void) { if (nrf_i2s_event_check(NRF_I2S, NRF_I2S_EVENT_TXPTRUPD)) { nrf_i2s_event_clear(NRF_I2S, NRF_I2S_EVENT_TXPTRUPD); m_cb.tx_ready = true; if (m_cb.use_tx && m_cb.buffers_needed) { m_cb.buffers_reused = true; } } if (nrf_i2s_event_check(NRF_I2S, NRF_I2S_EVENT_RXPTRUPD)) { nrf_i2s_event_clear(NRF_I2S, NRF_I2S_EVENT_RXPTRUPD); m_cb.rx_ready = true; if (m_cb.use_rx && m_cb.buffers_needed) { m_cb.buffers_reused = true; } } if (nrf_i2s_event_check(NRF_I2S, NRF_I2S_EVENT_STOPPED)) { nrf_i2s_event_clear(NRF_I2S, NRF_I2S_EVENT_STOPPED); nrf_i2s_int_disable(NRF_I2S, NRF_I2S_INT_STOPPED_MASK); nrf_i2s_disable(NRF_I2S); // When stopped, release all buffers, including these scheduled for // the next transfer. m_cb.handler(&m_cb.current_buffers, 0); m_cb.handler(&m_cb.next_buffers, 0); m_cb.state = NRFX_DRV_STATE_INITIALIZED; NRFX_LOG_INFO("Stopped."); } else { // Check if the requested transfer has been completed: // - full-duplex mode if ((m_cb.use_tx && m_cb.use_rx && m_cb.tx_ready && m_cb.rx_ready) || // - TX only mode (!m_cb.use_rx && m_cb.tx_ready) || // - RX only mode (!m_cb.use_tx && m_cb.rx_ready)) { m_cb.tx_ready = false; m_cb.rx_ready = false; // If the application did not supply the buffers for the next // part of the transfer until this moment, the current buffers // cannot be released, since the I2S peripheral already started // using them. Signal this situation to the application by // passing NULL instead of the structure with released buffers. if (m_cb.buffers_reused) { m_cb.buffers_reused = false; // This will most likely be set at this point. However, there is // a small time window between TXPTRUPD and RXPTRUPD events, // and it is theoretically possible that next buffers will be // set in this window, so to be sure this flag is set to true, // set it explicitly. m_cb.buffers_needed = true; m_cb.handler(NULL, NRFX_I2S_STATUS_NEXT_BUFFERS_NEEDED); } else { // Buffers that have been used by the I2S peripheral (current) // are now released and will be returned to the application, // and the ones scheduled to be used as next become the current // ones. nrfx_i2s_buffers_t released_buffers = m_cb.current_buffers; m_cb.current_buffers = m_cb.next_buffers; m_cb.next_buffers.p_rx_buffer = NULL; m_cb.next_buffers.p_tx_buffer = NULL; m_cb.buffers_needed = true; m_cb.handler(&released_buffers, NRFX_I2S_STATUS_NEXT_BUFFERS_NEEDED); } } } }