tests/drivers/i2s/i2s_api/src/test_i2s_loopback.c - third_party/github/zephyrproject-rtos/zephyr - Git at Google

 /*
  * Copyright (c) 2017 comsuisse AG
  *
  * SPDX-License-Identifier: Apache-2.0
  */


 #include <zephyr/kernel.h>
 #include <zephyr/ztest.h>
 #include <zephyr/drivers/i2s.h>
 #include "i2s_api_test.h"

 static ZTEST_DMEM const struct device *dev_i2s_rx;
 static ZTEST_DMEM const struct device *dev_i2s_tx;

 /** Configure I2S TX transfer. */
 void test_i2s_tx_transfer_configure_0(void)
 {
 	int ret;

 	dev_i2s_tx = device_get_binding(I2S_DEV_NAME_TX);
 	zassert_not_null(dev_i2s_tx, "device " I2S_DEV_NAME_TX " not found");

 	ret = configure_stream(dev_i2s_tx, I2S_DIR_TX);
 	zassert_equal(ret, TC_PASS);
 }

 /** Configure I2S RX transfer. */
 void test_i2s_rx_transfer_configure_0(void)
 {
 	int ret;

 	dev_i2s_rx = device_get_binding(I2S_DEV_NAME_RX);
 	zassert_not_null(dev_i2s_rx, "device " I2S_DEV_NAME_RX " not found");

 	ret = configure_stream(dev_i2s_rx, I2S_DIR_RX);
 	zassert_equal(ret, TC_PASS);
 }

 /** @brief Short I2S transfer.
  *
  * - TX stream START trigger starts transmission.
  * - RX stream START trigger starts reception.
  * - sending / receiving a short sequence of data returns success.
  * - TX stream DRAIN trigger empties the transmit queue.
  * - RX stream STOP trigger stops reception.
  */
 void test_i2s_transfer_short(void)
 {
 	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
 		TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
 		ztest_test_skip();
 		return;
 	}

 	int ret;

 	/* Prefill TX queue */
 	ret = tx_block_write(dev_i2s_tx, 0, 0);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d->OK\n", 1);

 	ret = tx_block_write(dev_i2s_tx, 1, 0);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d->OK\n", 2);

 	/* Start reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "RX START trigger failed");

 	/* Start transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "TX START trigger failed");

 	ret = rx_block_read(dev_i2s_rx, 0);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d<-OK\n", 1);

 	ret = tx_block_write(dev_i2s_tx, 2, 0);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d->OK\n", 3);

 	/* All data written, drain TX queue and stop the transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
 	zassert_equal(ret, 0, "TX DRAIN trigger failed");

 	ret = rx_block_read(dev_i2s_rx, 1);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d<-OK\n", 2);

 	/* All but one data block read, stop reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
 	zassert_equal(ret, 0, "RX STOP trigger failed");

 	ret = rx_block_read(dev_i2s_rx, 2);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d<-OK\n", 3);

 	/* TODO: Verify the interface is in READY state when i2s_state_get
 	 * function is available.
 	 */
 }

 #define TEST_I2S_TRANSFER_LONG_REPEAT_COUNT  100

 /** @brief Long I2S transfer.
  *
  * - TX stream START trigger starts transmission.
  * - RX stream START trigger starts reception.
  * - sending / receiving a long sequence of data returns success.
  * - TX stream DRAIN trigger empties the transmit queue.
  * - RX stream STOP trigger stops reception.
  */
 void test_i2s_transfer_long(void)
 {
 	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
 		TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
 		ztest_test_skip();
 		return;
 	}

 	int ret;

 	/* Prefill TX queue */
 	ret = tx_block_write(dev_i2s_tx, 0, 0);
 	zassert_equal(ret, TC_PASS);

 	/* Start reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "RX START trigger failed");

 	/* Start transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "TX START trigger failed");

 	for (int i = 0; i < TEST_I2S_TRANSFER_LONG_REPEAT_COUNT; i++) {
 		ret = tx_block_write(dev_i2s_tx, 0, 0);
 		zassert_equal(ret, TC_PASS);

 		ret = rx_block_read(dev_i2s_rx, 0);
 		zassert_equal(ret, TC_PASS);
 	}

 	/* All data written, flush TX queue and stop the transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
 	zassert_equal(ret, 0, "TX DRAIN trigger failed");

 	/* All but one data block read, stop reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
 	zassert_equal(ret, 0, "RX STOP trigger failed");

 	ret = rx_block_read(dev_i2s_rx, 0);
 	zassert_equal(ret, TC_PASS);

 	/* TODO: Verify the interface is in READY state when i2s_state_get
 	 * function is available.
 	 */
 }

 /** @brief RX sync start.
  *
  * - TX stream START trigger starts transmission.
  * - sending RX stream START trigger after a delay starts reception on the next
  *   word select sync event at the start of the frame.
  * - TX stream DROP trigger stops transmission and clears the transmit queue.
  * - RX stream DROP trigger stops reception and clears the receive queue.
  */
 void test_i2s_rx_sync_start(void)
 {
 	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
 		TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
 		ztest_test_skip();
 		return;
 	}

 	size_t rx_size;
 	int ret;
 	char buf[BLOCK_SIZE];

 	/* Prefill TX queue */
 	for (int n = 0; n < NUM_TX_BLOCKS; n++) {
 		fill_buf_const((uint16_t *)buf, 1, 2);
 		ret = i2s_buf_write(dev_i2s_tx, buf, BLOCK_SIZE);
 		zassert_equal(ret, TC_PASS);
 		TC_PRINT("%d->OK\n", n);
 	}

 	/* Start transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "TX START trigger failed");

 	k_busy_wait(75);

 	/* Start reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "RX START trigger failed");
 	ret = i2s_buf_read(dev_i2s_rx, buf, &rx_size);
 	zassert_equal(ret, TC_PASS);
 	ret = verify_buf_const((uint16_t *)buf, 1, 2);

 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d<-OK\n", 1);

 	/* All data written, drop TX, RX queue and stop the transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DROP);
 	zassert_equal(ret, 0, "TX DROP trigger failed");

 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_DROP);
 	zassert_equal(ret, 0, "RX DROP trigger failed");

 	/* TODO: Verify the interface is in READY state when i2s_state_get
 	 * function is available.
 	 */
 }

 /** @brief Timeout on RX queue empty.
  *
  * - Reading empty RX queue in READY state returns time out error.
  */
 void test_i2s_rx_empty_timeout(void)
 {
 	size_t rx_size;
 	int ret;
 	char buf[BLOCK_SIZE];

 	ret = i2s_buf_read(dev_i2s_rx, buf, &rx_size);
 	zassert_equal(ret, -EAGAIN, "i2s_read did not timed out");
 }

 /** @brief Re-start I2S transfer.
  *
  * - STOP trigger stops transfer / reception at the end of the current block,
  *   consecutive START trigger restarts transfer / reception with the next data
  *   block.
  */
 void test_i2s_transfer_restart(void)
 {
 	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
 		TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
 		ztest_test_skip();
 		return;
 	}

 	int ret;

 	/* Prefill TX queue */
 	ret = tx_block_write(dev_i2s_tx, 0, 0);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d->OK\n", 1);

 	ret = tx_block_write(dev_i2s_tx, 1, 0);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d->OK\n", 2);

 	/* Start reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "RX START trigger failed");

 	/* Start transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "TX START trigger failed");

 	/* Stop transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_STOP);
 	zassert_equal(ret, 0, "TX STOP trigger failed");

 	/* Stop reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
 	zassert_equal(ret, 0, "RX STOP trigger failed");

 	ret = rx_block_read(dev_i2s_rx, 0);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d<-OK\n", 1);

 	TC_PRINT("Stop transmission\n");

 	/* Keep interface inactive */
 	k_sleep(K_MSEC(1000));

 	TC_PRINT("Start transmission\n");

 	/* Prefill TX queue */
 	ret = tx_block_write(dev_i2s_tx, 2, 0);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d->OK\n", 3);

 	/* Start reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "RX START trigger failed");

 	/* Start transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "TX START trigger failed");

 	/* All data written, drain TX queue and stop the transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
 	zassert_equal(ret, 0, "TX DRAIN trigger failed");

 	ret = rx_block_read(dev_i2s_rx, 1);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d<-OK\n", 2);

 	/* All but one data block read, stop reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
 	zassert_equal(ret, 0, "RX STOP trigger failed");

 	ret = rx_block_read(dev_i2s_rx, 2);
 	zassert_equal(ret, TC_PASS);
 	TC_PRINT("%d<-OK\n", 3);
 }

 /** @brief RX buffer overrun.
  *
  * - In case of RX buffer overrun it is possible to read out RX data blocks
  *   that are stored in the RX queue.
  * - Reading from an empty RX queue when the RX buffer overrun occurred results
  *   in an error.
  * - Sending PREPARE trigger after the RX buffer overrun occurred changes
  *   the interface state to READY.
  */
 void test_i2s_transfer_rx_overrun(void)
 {
 	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
 		TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
 		ztest_test_skip();
 		return;
 	}

 	size_t rx_size;
 	int ret;
 	char rx_buf[BLOCK_SIZE];

 	/* Prefill TX queue */
 	ret = tx_block_write(dev_i2s_tx, 0, 0);
 	zassert_equal(ret, TC_PASS);

 	/* Start reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "RX START trigger failed");

 	/* Start transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "TX START trigger failed");

 	for (int i = 0; i < NUM_RX_BLOCKS; i++) {
 		ret = tx_block_write(dev_i2s_tx, 0, 0);
 		zassert_equal(ret, TC_PASS);
 	}

 	/* All data written, flush TX queue and stop the transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
 	zassert_equal(ret, 0, "TX DRAIN trigger failed");

 	/* Wait for transmission to finish */
 	k_sleep(K_MSEC(200));

 	/* Read one data block, expect success even if RX queue is already in
 	 * the error state.
 	 */
 	ret = rx_block_read(dev_i2s_rx, 0);
 	zassert_equal(ret, TC_PASS);

 	/* Attempt to read more data blocks than are available in the RX queue */
 	for (int i = 0; i < NUM_RX_BLOCKS; i++) {
 		ret = i2s_buf_read(dev_i2s_rx, rx_buf, &rx_size);
 		if (ret != 0) {
 			break;
 		}
 	}
 	zassert_equal(ret, -EIO, "RX overrun error not detected");

 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_PREPARE);
 	zassert_equal(ret, 0, "RX PREPARE trigger failed");

 	/* Transmit and receive one more data block */
 	ret = tx_block_write(dev_i2s_tx, 0, 0);
 	zassert_equal(ret, TC_PASS);
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "RX START trigger failed");
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "TX START trigger failed");
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
 	zassert_equal(ret, 0, "TX DRAIN trigger failed");
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
 	zassert_equal(ret, 0, "RX STOP trigger failed");
 	ret = rx_block_read(dev_i2s_rx, 0);
 	zassert_equal(ret, TC_PASS);

 	k_sleep(K_MSEC(200));
 }

 /** @brief TX buffer underrun.
  *
  * - An attempt to write to the TX queue when TX buffer underrun has occurred
  *   results in an error.
  * - Sending PREPARE trigger after the TX buffer underrun occurred changes
  *   the interface state to READY.
  */
 void test_i2s_transfer_tx_underrun(void)
 {
 	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
 		TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
 		ztest_test_skip();
 		return;
 	}

 	int ret;

 	/* Prefill TX queue */
 	ret = tx_block_write(dev_i2s_tx, 0, 0);
 	zassert_equal(ret, TC_PASS);

 	/* Start reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "RX START trigger failed");

 	/* Start transmission */
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "TX START trigger failed");

 	/* Stop reception */
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
 	zassert_equal(ret, 0, "RX STOP trigger failed");

 	ret = rx_block_read(dev_i2s_rx, 0);
 	zassert_equal(ret, TC_PASS);

 	k_sleep(K_MSEC(200));

 	/* Write one more TX data block, expect an error */
 	ret = tx_block_write(dev_i2s_tx, 2, -EIO);
 	zassert_equal(ret, TC_PASS);

 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_PREPARE);
 	zassert_equal(ret, 0, "TX PREPARE trigger failed");

 	k_sleep(K_MSEC(200));

 	/* Transmit and receive two more data blocks */
 	ret = tx_block_write(dev_i2s_tx, 1, 0);
 	zassert_equal(ret, TC_PASS);
 	ret = tx_block_write(dev_i2s_tx, 1, 0);
 	zassert_equal(ret, TC_PASS);
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "RX START trigger failed");
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
 	zassert_equal(ret, 0, "TX START trigger failed");
 	ret = rx_block_read(dev_i2s_rx, 1);
 	zassert_equal(ret, TC_PASS);
 	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
 	zassert_equal(ret, 0, "TX DRAIN trigger failed");
 	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
 	zassert_equal(ret, 0, "RX STOP trigger failed");
 	ret = rx_block_read(dev_i2s_rx, 1);
 	zassert_equal(ret, TC_PASS);

 	k_sleep(K_MSEC(200));
 }
	/*
	* Copyright (c) 2017 comsuisse AG
	*
	* SPDX-License-Identifier: Apache-2.0
	*/


	#include <zephyr/kernel.h>
	#include <zephyr/ztest.h>
	#include <zephyr/drivers/i2s.h>
	#include "i2s_api_test.h"

	static ZTEST_DMEM const struct device *dev_i2s_rx;
	static ZTEST_DMEM const struct device *dev_i2s_tx;

	/** Configure I2S TX transfer. */
	void test_i2s_tx_transfer_configure_0(void)
	{
	int ret;

	dev_i2s_tx = device_get_binding(I2S_DEV_NAME_TX);
	zassert_not_null(dev_i2s_tx, "device " I2S_DEV_NAME_TX " not found");

	ret = configure_stream(dev_i2s_tx, I2S_DIR_TX);
	zassert_equal(ret, TC_PASS);
	}

	/** Configure I2S RX transfer. */
	void test_i2s_rx_transfer_configure_0(void)
	{
	int ret;

	dev_i2s_rx = device_get_binding(I2S_DEV_NAME_RX);
	zassert_not_null(dev_i2s_rx, "device " I2S_DEV_NAME_RX " not found");

	ret = configure_stream(dev_i2s_rx, I2S_DIR_RX);
	zassert_equal(ret, TC_PASS);
	}

	/** @brief Short I2S transfer.
	*
	* - TX stream START trigger starts transmission.
	* - RX stream START trigger starts reception.
	* - sending / receiving a short sequence of data returns success.
	* - TX stream DRAIN trigger empties the transmit queue.
	* - RX stream STOP trigger stops reception.
	*/
	void test_i2s_transfer_short(void)
	{
	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
	TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
	ztest_test_skip();
	return;
	}

	int ret;

	/* Prefill TX queue */
	ret = tx_block_write(dev_i2s_tx, 0, 0);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d->OK\n", 1);

	ret = tx_block_write(dev_i2s_tx, 1, 0);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d->OK\n", 2);

	/* Start reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "RX START trigger failed");

	/* Start transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "TX START trigger failed");

	ret = rx_block_read(dev_i2s_rx, 0);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d<-OK\n", 1);

	ret = tx_block_write(dev_i2s_tx, 2, 0);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d->OK\n", 3);

	/* All data written, drain TX queue and stop the transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
	zassert_equal(ret, 0, "TX DRAIN trigger failed");

	ret = rx_block_read(dev_i2s_rx, 1);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d<-OK\n", 2);

	/* All but one data block read, stop reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
	zassert_equal(ret, 0, "RX STOP trigger failed");

	ret = rx_block_read(dev_i2s_rx, 2);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d<-OK\n", 3);

	/* TODO: Verify the interface is in READY state when i2s_state_get
	* function is available.
	*/
	}

	#define TEST_I2S_TRANSFER_LONG_REPEAT_COUNT 100

	/** @brief Long I2S transfer.
	*
	* - TX stream START trigger starts transmission.
	* - RX stream START trigger starts reception.
	* - sending / receiving a long sequence of data returns success.
	* - TX stream DRAIN trigger empties the transmit queue.
	* - RX stream STOP trigger stops reception.
	*/
	void test_i2s_transfer_long(void)
	{
	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
	TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
	ztest_test_skip();
	return;
	}

	int ret;

	/* Prefill TX queue */
	ret = tx_block_write(dev_i2s_tx, 0, 0);
	zassert_equal(ret, TC_PASS);

	/* Start reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "RX START trigger failed");

	/* Start transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "TX START trigger failed");

	for (int i = 0; i < TEST_I2S_TRANSFER_LONG_REPEAT_COUNT; i++) {
	ret = tx_block_write(dev_i2s_tx, 0, 0);
	zassert_equal(ret, TC_PASS);

	ret = rx_block_read(dev_i2s_rx, 0);
	zassert_equal(ret, TC_PASS);
	}

	/* All data written, flush TX queue and stop the transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
	zassert_equal(ret, 0, "TX DRAIN trigger failed");

	/* All but one data block read, stop reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
	zassert_equal(ret, 0, "RX STOP trigger failed");

	ret = rx_block_read(dev_i2s_rx, 0);
	zassert_equal(ret, TC_PASS);

	/* TODO: Verify the interface is in READY state when i2s_state_get
	* function is available.
	*/
	}

	/** @brief RX sync start.
	*
	* - TX stream START trigger starts transmission.
	* - sending RX stream START trigger after a delay starts reception on the next
	* word select sync event at the start of the frame.
	* - TX stream DROP trigger stops transmission and clears the transmit queue.
	* - RX stream DROP trigger stops reception and clears the receive queue.
	*/
	void test_i2s_rx_sync_start(void)
	{
	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
	TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
	ztest_test_skip();
	return;
	}

	size_t rx_size;
	int ret;
	char buf[BLOCK_SIZE];

	/* Prefill TX queue */
	for (int n = 0; n < NUM_TX_BLOCKS; n++) {
	fill_buf_const((uint16_t *)buf, 1, 2);
	ret = i2s_buf_write(dev_i2s_tx, buf, BLOCK_SIZE);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d->OK\n", n);
	}

	/* Start transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "TX START trigger failed");

	k_busy_wait(75);

	/* Start reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "RX START trigger failed");
	ret = i2s_buf_read(dev_i2s_rx, buf, &rx_size);
	zassert_equal(ret, TC_PASS);
	ret = verify_buf_const((uint16_t *)buf, 1, 2);

	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d<-OK\n", 1);

	/* All data written, drop TX, RX queue and stop the transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DROP);
	zassert_equal(ret, 0, "TX DROP trigger failed");

	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_DROP);
	zassert_equal(ret, 0, "RX DROP trigger failed");

	/* TODO: Verify the interface is in READY state when i2s_state_get
	* function is available.
	*/
	}

	/** @brief Timeout on RX queue empty.
	*
	* - Reading empty RX queue in READY state returns time out error.
	*/
	void test_i2s_rx_empty_timeout(void)
	{
	size_t rx_size;
	int ret;
	char buf[BLOCK_SIZE];

	ret = i2s_buf_read(dev_i2s_rx, buf, &rx_size);
	zassert_equal(ret, -EAGAIN, "i2s_read did not timed out");
	}

	/** @brief Re-start I2S transfer.
	*
	* - STOP trigger stops transfer / reception at the end of the current block,
	* consecutive START trigger restarts transfer / reception with the next data
	* block.
	*/
	void test_i2s_transfer_restart(void)
	{
	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
	TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
	ztest_test_skip();
	return;
	}

	int ret;

	/* Prefill TX queue */
	ret = tx_block_write(dev_i2s_tx, 0, 0);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d->OK\n", 1);

	ret = tx_block_write(dev_i2s_tx, 1, 0);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d->OK\n", 2);

	/* Start reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "RX START trigger failed");

	/* Start transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "TX START trigger failed");

	/* Stop transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_STOP);
	zassert_equal(ret, 0, "TX STOP trigger failed");

	/* Stop reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
	zassert_equal(ret, 0, "RX STOP trigger failed");

	ret = rx_block_read(dev_i2s_rx, 0);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d<-OK\n", 1);

	TC_PRINT("Stop transmission\n");

	/* Keep interface inactive */
	k_sleep(K_MSEC(1000));

	TC_PRINT("Start transmission\n");

	/* Prefill TX queue */
	ret = tx_block_write(dev_i2s_tx, 2, 0);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d->OK\n", 3);

	/* Start reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "RX START trigger failed");

	/* Start transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "TX START trigger failed");

	/* All data written, drain TX queue and stop the transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
	zassert_equal(ret, 0, "TX DRAIN trigger failed");

	ret = rx_block_read(dev_i2s_rx, 1);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d<-OK\n", 2);

	/* All but one data block read, stop reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
	zassert_equal(ret, 0, "RX STOP trigger failed");

	ret = rx_block_read(dev_i2s_rx, 2);
	zassert_equal(ret, TC_PASS);
	TC_PRINT("%d<-OK\n", 3);
	}

	/** @brief RX buffer overrun.
	*
	* - In case of RX buffer overrun it is possible to read out RX data blocks
	* that are stored in the RX queue.
	* - Reading from an empty RX queue when the RX buffer overrun occurred results
	* in an error.
	* - Sending PREPARE trigger after the RX buffer overrun occurred changes
	* the interface state to READY.
	*/
	void test_i2s_transfer_rx_overrun(void)
	{
	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
	TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
	ztest_test_skip();
	return;
	}

	size_t rx_size;
	int ret;
	char rx_buf[BLOCK_SIZE];

	/* Prefill TX queue */
	ret = tx_block_write(dev_i2s_tx, 0, 0);
	zassert_equal(ret, TC_PASS);

	/* Start reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "RX START trigger failed");

	/* Start transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "TX START trigger failed");

	for (int i = 0; i < NUM_RX_BLOCKS; i++) {
	ret = tx_block_write(dev_i2s_tx, 0, 0);
	zassert_equal(ret, TC_PASS);
	}

	/* All data written, flush TX queue and stop the transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
	zassert_equal(ret, 0, "TX DRAIN trigger failed");

	/* Wait for transmission to finish */
	k_sleep(K_MSEC(200));

	/* Read one data block, expect success even if RX queue is already in
	* the error state.
	*/
	ret = rx_block_read(dev_i2s_rx, 0);
	zassert_equal(ret, TC_PASS);

	/* Attempt to read more data blocks than are available in the RX queue */
	for (int i = 0; i < NUM_RX_BLOCKS; i++) {
	ret = i2s_buf_read(dev_i2s_rx, rx_buf, &rx_size);
	if (ret != 0) {
	break;
	}
	}
	zassert_equal(ret, -EIO, "RX overrun error not detected");

	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_PREPARE);
	zassert_equal(ret, 0, "RX PREPARE trigger failed");

	/* Transmit and receive one more data block */
	ret = tx_block_write(dev_i2s_tx, 0, 0);
	zassert_equal(ret, TC_PASS);
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "RX START trigger failed");
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "TX START trigger failed");
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
	zassert_equal(ret, 0, "TX DRAIN trigger failed");
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
	zassert_equal(ret, 0, "RX STOP trigger failed");
	ret = rx_block_read(dev_i2s_rx, 0);
	zassert_equal(ret, TC_PASS);

	k_sleep(K_MSEC(200));
	}

	/** @brief TX buffer underrun.
	*
	* - An attempt to write to the TX queue when TX buffer underrun has occurred
	* results in an error.
	* - Sending PREPARE trigger after the TX buffer underrun occurred changes
	* the interface state to READY.
	*/
	void test_i2s_transfer_tx_underrun(void)
	{
	if (IS_ENABLED(CONFIG_I2S_TEST_USE_I2S_DIR_BOTH)) {
	TC_PRINT("RX/TX transfer requires use of I2S_DIR_BOTH.\n");
	ztest_test_skip();
	return;
	}

	int ret;

	/* Prefill TX queue */
	ret = tx_block_write(dev_i2s_tx, 0, 0);
	zassert_equal(ret, TC_PASS);

	/* Start reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "RX START trigger failed");

	/* Start transmission */
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "TX START trigger failed");

	/* Stop reception */
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
	zassert_equal(ret, 0, "RX STOP trigger failed");

	ret = rx_block_read(dev_i2s_rx, 0);
	zassert_equal(ret, TC_PASS);

	k_sleep(K_MSEC(200));

	/* Write one more TX data block, expect an error */
	ret = tx_block_write(dev_i2s_tx, 2, -EIO);
	zassert_equal(ret, TC_PASS);

	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_PREPARE);
	zassert_equal(ret, 0, "TX PREPARE trigger failed");

	k_sleep(K_MSEC(200));

	/* Transmit and receive two more data blocks */
	ret = tx_block_write(dev_i2s_tx, 1, 0);
	zassert_equal(ret, TC_PASS);
	ret = tx_block_write(dev_i2s_tx, 1, 0);
	zassert_equal(ret, TC_PASS);
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "RX START trigger failed");
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_START);
	zassert_equal(ret, 0, "TX START trigger failed");
	ret = rx_block_read(dev_i2s_rx, 1);
	zassert_equal(ret, TC_PASS);
	ret = i2s_trigger(dev_i2s_tx, I2S_DIR_TX, I2S_TRIGGER_DRAIN);
	zassert_equal(ret, 0, "TX DRAIN trigger failed");
	ret = i2s_trigger(dev_i2s_rx, I2S_DIR_RX, I2S_TRIGGER_STOP);
	zassert_equal(ret, 0, "RX STOP trigger failed");
	ret = rx_block_read(dev_i2s_rx, 1);
	zassert_equal(ret, TC_PASS);

	k_sleep(K_MSEC(200));
	}