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_stop(void)
{
NRFX_ASSERT(m_cb.state != NRFX_DRV_STATE_UNINITIALIZED);
m_cb.buffers_needed = false;
// First disable interrupts, then trigger the STOP task, so no spurious
// RXPTRUPD and TXPTRUPD events (see nRF52 anomaly 55) are 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);
#if USE_WORKAROUND_FOR_ANOMALY_194
*((volatile uint32_t *)0x40025038) = 1;
*((volatile uint32_t *)0x4002503C) = 1;
#endif
}
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);
}
}
}
}
