drivers/spi/spi_mcux_flexio.c - third_party/github/zephyrproject-rtos/zephyr - Git at Google

 /*
  * Copyright (c) 2024, STRIM, ALC
  * Copyright 2024 NXP
  *
  * SPDX-License-Identifier: Apache-2.0
  */

 #define DT_DRV_COMPAT nxp_flexio_spi

 #include <errno.h>
 #include <zephyr/drivers/spi.h>
 #include <zephyr/drivers/clock_control.h>
 #include <fsl_flexio_spi.h>
 #include <zephyr/logging/log.h>
 #include <zephyr/drivers/pinctrl.h>
 #include <zephyr/drivers/misc/nxp_flexio/nxp_flexio.h>

 LOG_MODULE_REGISTER(spi_mcux_flexio_spi, CONFIG_SPI_LOG_LEVEL);

 #include "spi_context.h"


 struct spi_mcux_flexio_config {
 	FLEXIO_SPI_Type *flexio_spi;
 	const struct device *flexio_dev;
 	const struct pinctrl_dev_config *pincfg;
 	const struct nxp_flexio_child *child;
 };

 struct spi_mcux_flexio_data {
 	const struct device *dev;
 	flexio_spi_master_handle_t handle;
 	struct spi_context ctx;
 	size_t transfer_len;
 	uint8_t transfer_flags;
 };


 static void spi_mcux_transfer_next_packet(const struct device *dev)
 {
 	const struct spi_mcux_flexio_config *config = dev->config;
 	struct spi_mcux_flexio_data *data = dev->data;
 	struct spi_context *ctx = &data->ctx;
 	flexio_spi_transfer_t transfer;
 	status_t status;

 	if ((ctx->tx_len == 0) && (ctx->rx_len == 0)) {
 		/* nothing left to rx or tx, we're done! */
 		spi_context_cs_control(&data->ctx, false);
 		spi_context_complete(&data->ctx, dev, 0);
 		return;
 	}

 	transfer.flags = kFLEXIO_SPI_csContinuous | data->transfer_flags;

 	if (ctx->tx_len == 0) {
 		/* rx only, nothing to tx */
 		transfer.txData = NULL;
 		transfer.rxData = ctx->rx_buf;
 		transfer.dataSize = ctx->rx_len;
 	} else if (ctx->rx_len == 0) {
 		/* tx only, nothing to rx */
 		transfer.txData = (uint8_t *) ctx->tx_buf;
 		transfer.rxData = NULL;
 		transfer.dataSize = ctx->tx_len;
 	} else if (ctx->tx_len == ctx->rx_len) {
 		/* rx and tx are the same length */
 		transfer.txData = (uint8_t *) ctx->tx_buf;
 		transfer.rxData = ctx->rx_buf;
 		transfer.dataSize = ctx->tx_len;
 	} else if (ctx->tx_len > ctx->rx_len) {
 		/* Break up the tx into multiple transfers so we don't have to
 		 * rx into a longer intermediate buffer. Leave chip select
 		 * active between transfers.
 		 */
 		transfer.txData = (uint8_t *) ctx->tx_buf;
 		transfer.rxData = ctx->rx_buf;
 		transfer.dataSize = ctx->rx_len;
 	} else {
 		/* Break up the rx into multiple transfers so we don't have to
 		 * tx from a longer intermediate buffer. Leave chip select
 		 * active between transfers.
 		 */
 		transfer.txData = (uint8_t *) ctx->tx_buf;
 		transfer.rxData = ctx->rx_buf;
 		transfer.dataSize = ctx->tx_len;
 	}

 	data->transfer_len = transfer.dataSize;

 	status = FLEXIO_SPI_MasterTransferNonBlocking(config->flexio_spi, &data->handle,
 						 &transfer);
 	if (status != kStatus_Success) {
 		LOG_ERR("Transfer could not start");
 	}
 }

 static int spi_mcux_flexio_isr(void *user_data)
 {
 	const struct device *dev = (const struct device *)user_data;
 	const struct spi_mcux_flexio_config *config = dev->config;
 	struct spi_mcux_flexio_data *data = dev->data;

 #if defined(CONFIG_SOC_SERIES_KE1XZ)
 	/* Wait until data transfer complete. */
 	WAIT_FOR((0U == (FLEXIO_SPI_GetStatusFlags(config->flexio_spi)
 		& (uint32_t)kFLEXIO_SPI_TxBufferEmptyFlag)), 100, NULL);
 #endif
 	FLEXIO_SPI_MasterTransferHandleIRQ(config->flexio_spi, &data->handle);

 	return 0;
 }

 static void spi_mcux_master_transfer_callback(FLEXIO_SPI_Type *flexio_spi,
 	flexio_spi_master_handle_t *handle, status_t status, void *userData)
 {
 	struct spi_mcux_flexio_data *data = userData;

 	spi_context_update_tx(&data->ctx, 1, data->transfer_len);
 	spi_context_update_rx(&data->ctx, 1, data->transfer_len);

 	spi_mcux_transfer_next_packet(data->dev);
 }

 static void spi_flexio_master_init(FLEXIO_SPI_Type *base, flexio_spi_master_config_t *masterConfig,
 	uint8_t pol, uint32_t srcClock_Hz)
 {
 	assert(base != NULL);
 	assert(masterConfig != NULL);

 	flexio_shifter_config_t shifterConfig;
 	flexio_timer_config_t timerConfig;
 	uint32_t ctrlReg  = 0;
 	uint16_t timerDiv = 0;
 	uint16_t timerCmp = 0;

 	/* Clear the shifterConfig & timerConfig struct. */
 	(void)memset(&shifterConfig, 0, sizeof(shifterConfig));
 	(void)memset(&timerConfig, 0, sizeof(timerConfig));

 	/* Configure FLEXIO SPI Master */
 	ctrlReg = base->flexioBase->CTRL;
 	ctrlReg &= ~(FLEXIO_CTRL_DOZEN_MASK | FLEXIO_CTRL_DBGE_MASK |
 			FLEXIO_CTRL_FASTACC_MASK | FLEXIO_CTRL_FLEXEN_MASK);
 	ctrlReg |= (FLEXIO_CTRL_DBGE(masterConfig->enableInDebug) |
 		FLEXIO_CTRL_FASTACC(masterConfig->enableFastAccess) |
 		FLEXIO_CTRL_FLEXEN(masterConfig->enableMaster));
 	if (!masterConfig->enableInDoze) {
 		ctrlReg |= FLEXIO_CTRL_DOZEN_MASK;
 	}

 	base->flexioBase->CTRL = ctrlReg;

 	/* Do hardware configuration. */
 	/* 1. Configure the shifter 0 for tx. */
 	shifterConfig.timerSelect = base->timerIndex[0];
 	shifterConfig.pinConfig   = kFLEXIO_PinConfigOutput;
 	shifterConfig.pinSelect   = base->SDOPinIndex;
 	shifterConfig.pinPolarity = kFLEXIO_PinActiveHigh;
 	shifterConfig.shifterMode = kFLEXIO_ShifterModeTransmit;
 	shifterConfig.inputSource = kFLEXIO_ShifterInputFromPin;
 	if (masterConfig->phase == kFLEXIO_SPI_ClockPhaseFirstEdge) {
 		shifterConfig.timerPolarity = kFLEXIO_ShifterTimerPolarityOnNegitive;
 		shifterConfig.shifterStop   = kFLEXIO_ShifterStopBitDisable;
 		shifterConfig.shifterStart  = kFLEXIO_ShifterStartBitDisabledLoadDataOnEnable;
 	} else {
 		shifterConfig.timerPolarity = kFLEXIO_ShifterTimerPolarityOnPositive;
 		shifterConfig.shifterStop   = kFLEXIO_ShifterStopBitLow;
 		shifterConfig.shifterStart  = kFLEXIO_ShifterStartBitDisabledLoadDataOnShift;
 	}

 	FLEXIO_SetShifterConfig(base->flexioBase, base->shifterIndex[0], &shifterConfig);

 	/* 2. Configure the shifter 1 for rx. */
 	shifterConfig.timerSelect  = base->timerIndex[0];
 	shifterConfig.pinConfig    = kFLEXIO_PinConfigOutputDisabled;
 	shifterConfig.pinSelect    = base->SDIPinIndex;
 	shifterConfig.pinPolarity  = kFLEXIO_PinActiveHigh;
 	shifterConfig.shifterMode  = kFLEXIO_ShifterModeReceive;
 	shifterConfig.inputSource  = kFLEXIO_ShifterInputFromPin;
 	shifterConfig.shifterStop  = kFLEXIO_ShifterStopBitDisable;
 	shifterConfig.shifterStart = kFLEXIO_ShifterStartBitDisabledLoadDataOnEnable;
 	if (masterConfig->phase == kFLEXIO_SPI_ClockPhaseFirstEdge) {
 		shifterConfig.timerPolarity = kFLEXIO_ShifterTimerPolarityOnPositive;
 	} else {
 		shifterConfig.timerPolarity = kFLEXIO_ShifterTimerPolarityOnNegitive;
 	}

 	FLEXIO_SetShifterConfig(base->flexioBase, base->shifterIndex[1], &shifterConfig);

 	/*3. Configure the timer 0 for SCK. */
 	timerConfig.triggerSelect   = FLEXIO_TIMER_TRIGGER_SEL_SHIFTnSTAT(base->shifterIndex[0]);
 	timerConfig.triggerPolarity = kFLEXIO_TimerTriggerPolarityActiveLow;
 	timerConfig.triggerSource   = kFLEXIO_TimerTriggerSourceInternal;
 	timerConfig.pinConfig       = kFLEXIO_PinConfigOutput;
 	timerConfig.pinSelect       = base->SCKPinIndex;
 	timerConfig.pinPolarity     = pol ? kFLEXIO_PinActiveLow : kFLEXIO_PinActiveHigh;
 	timerConfig.timerMode       = kFLEXIO_TimerModeDual8BitBaudBit;
 	timerConfig.timerOutput     = kFLEXIO_TimerOutputZeroNotAffectedByReset;
 	timerConfig.timerDecrement  = kFLEXIO_TimerDecSrcOnFlexIOClockShiftTimerOutput;
 	timerConfig.timerReset      = kFLEXIO_TimerResetNever;
 	timerConfig.timerDisable    = kFLEXIO_TimerDisableOnTimerCompare;
 	timerConfig.timerEnable     = kFLEXIO_TimerEnableOnTriggerHigh;
 	timerConfig.timerStop       = kFLEXIO_TimerStopBitEnableOnTimerDisable;
 	timerConfig.timerStart      = kFLEXIO_TimerStartBitEnabled;
 	/* Low 8-bits are used to configure baudrate. */
 	timerDiv = (uint16_t)(srcClock_Hz / masterConfig->baudRate_Bps);
 	timerDiv = timerDiv / 2U - 1U;
 	/* High 8-bits are used to configure shift clock edges(transfer width). */
 	timerCmp = ((uint16_t)masterConfig->dataMode * 2U - 1U) << 8U;
 	timerCmp |= timerDiv;

 	timerConfig.timerCompare = timerCmp;

 	FLEXIO_SetTimerConfig(base->flexioBase, base->timerIndex[0], &timerConfig);
 }

 static int spi_mcux_flexio_configure(const struct device *dev,
 	const struct spi_config *spi_cfg)
 {
 	const struct spi_mcux_flexio_config *config = dev->config;
 	struct spi_mcux_flexio_data *data = dev->data;

 	flexio_spi_master_config_t master_config;
 	uint32_t clock_freq;
 	uint32_t word_size;

 	if (spi_context_configured(&data->ctx, spi_cfg)) {
 		/* This configuration is already in use */
 		return 0;
 	}

 	if (spi_cfg->operation & SPI_HALF_DUPLEX) {
 		LOG_ERR("Half-duplex not supported");
 		return -ENOTSUP;
 	}

 	if (SPI_OP_MODE_GET(spi_cfg->operation) != SPI_OP_MODE_MASTER) {
 		LOG_ERR("Mode Slave not supported");
 		return -ENOTSUP;
 	}

 	FLEXIO_SPI_MasterGetDefaultConfig(&master_config);

 	word_size = SPI_WORD_SIZE_GET(spi_cfg->operation);
 	if ((word_size != 8) && (word_size != 16) && (word_size != 32)) {
 		LOG_ERR("Word size %d must be 8, 16 or 32", word_size);
 		return -EINVAL;
 	}
 	master_config.dataMode = word_size;

 	if (spi_cfg->operation & SPI_TRANSFER_LSB) {
 		if (word_size == 8) {
 			data->transfer_flags = kFLEXIO_SPI_8bitLsb;
 		} else if (word_size == 16) {
 			data->transfer_flags = kFLEXIO_SPI_16bitLsb;
 		} else {
 			data->transfer_flags = kFLEXIO_SPI_32bitLsb;
 		}
 	} else {
 		if (word_size == 8) {
 			data->transfer_flags = kFLEXIO_SPI_8bitMsb;
 		} else if (word_size == 16) {
 			data->transfer_flags = kFLEXIO_SPI_16bitMsb;
 		} else {
 			data->transfer_flags = kFLEXIO_SPI_32bitMsb;
 		}
 	}

 	if (nxp_flexio_get_rate(config->flexio_dev, &clock_freq)) {
 		return -EINVAL;
 	}

 	master_config.phase =
 		(SPI_MODE_GET(spi_cfg->operation) & SPI_MODE_CPHA)
 		? kFLEXIO_SPI_ClockPhaseSecondEdge
 		: kFLEXIO_SPI_ClockPhaseFirstEdge;

 	master_config.baudRate_Bps = spi_cfg->frequency;
 	spi_flexio_master_init(config->flexio_spi, &master_config,
 		(SPI_MODE_GET(spi_cfg->operation) & SPI_MODE_CPOL), clock_freq);

 	FLEXIO_SPI_MasterTransferCreateHandle(config->flexio_spi, &data->handle,
 					spi_mcux_master_transfer_callback,
 					data);
 	/* No SetDummyData() for FlexIO_SPI */

 	data->ctx.config = spi_cfg;

 	return 0;
 }


 static int transceive(const struct device *dev,
 			const struct spi_config *spi_cfg,
 			const struct spi_buf_set *tx_bufs,
 			const struct spi_buf_set *rx_bufs,
 			bool asynchronous,
 			spi_callback_t cb,
 			void *userdata)
 {
 	const struct spi_mcux_flexio_config *config = dev->config;
 	struct spi_mcux_flexio_data *data = dev->data;
 	int ret;

 	spi_context_lock(&data->ctx, asynchronous, cb, userdata, spi_cfg);

 	nxp_flexio_lock(config->flexio_dev);
 	ret = spi_mcux_flexio_configure(dev, spi_cfg);
 	nxp_flexio_unlock(config->flexio_dev);
 	if (ret) {
 		goto out;
 	}

 	spi_context_buffers_setup(&data->ctx, tx_bufs, rx_bufs, 1);

 	spi_context_cs_control(&data->ctx, true);

 	nxp_flexio_lock(config->flexio_dev);
 	nxp_flexio_irq_disable(config->flexio_dev);

 	spi_mcux_transfer_next_packet(dev);

 	nxp_flexio_irq_enable(config->flexio_dev);
 	nxp_flexio_unlock(config->flexio_dev);

 	ret = spi_context_wait_for_completion(&data->ctx);
 out:
 	spi_context_release(&data->ctx, ret);

 	return ret;
 }

 static int spi_mcux_transceive(const struct device *dev,
 				const struct spi_config *spi_cfg,
 				const struct spi_buf_set *tx_bufs,
 				const struct spi_buf_set *rx_bufs)
 {
 	return transceive(dev, spi_cfg, tx_bufs, rx_bufs, false, NULL, NULL);
 }

 #ifdef CONFIG_SPI_ASYNC
 static int spi_mcux_transceive_async(const struct device *dev,
 				const struct spi_config *spi_cfg,
 				const struct spi_buf_set *tx_bufs,
 				const struct spi_buf_set *rx_bufs,
 				spi_callback_t cb,
 				void *userdata)
 {
 	return transceive(dev, spi_cfg, tx_bufs, rx_bufs, true, cb, userdata);
 }
 #endif /* CONFIG_SPI_ASYNC */

 static int spi_mcux_release(const struct device *dev,
 				const struct spi_config *spi_cfg)
 {
 	struct spi_mcux_flexio_data *data = dev->data;

 	spi_context_unlock_unconditionally(&data->ctx);

 	return 0;
 }

 static int spi_mcux_init(const struct device *dev)
 {
 	const struct spi_mcux_flexio_config *config = dev->config;
 	struct spi_mcux_flexio_data *data = dev->data;
 	int err;

 	err = nxp_flexio_child_attach(config->flexio_dev, config->child);
 	if (err < 0) {
 		return err;
 	}

 	err = spi_context_cs_configure_all(&data->ctx);
 	if (err < 0) {
 		return err;
 	}

 	spi_context_unlock_unconditionally(&data->ctx);

 	data->dev = dev;

 	/* TODO: DMA */

 	err = pinctrl_apply_state(config->pincfg, PINCTRL_STATE_DEFAULT);
 	if (err) {
 		return err;
 	}

 	spi_context_unlock_unconditionally(&data->ctx);

 	return 0;
 }

 static const struct spi_driver_api spi_mcux_driver_api = {
 	.transceive = spi_mcux_transceive,
 #ifdef CONFIG_SPI_ASYNC
 	.transceive_async = spi_mcux_transceive_async,
 #endif
 	.release = spi_mcux_release,
 };

 #define SPI_MCUX_FLEXIO_SPI_INIT(n)					\
 	PINCTRL_DT_INST_DEFINE(n);					\
 									\
 	static FLEXIO_SPI_Type flexio_spi_##n = {			\
 		.flexioBase = (FLEXIO_Type *)DT_REG_ADDR(DT_INST_PARENT(n)), \
 		.SDOPinIndex = DT_INST_PROP(n, sdo_pin),		\
 		.SDIPinIndex = DT_INST_PROP(n, sdi_pin),		\
 		.SCKPinIndex = DT_INST_PROP(n, sck_pin),		\
 	};								\
 									\
 	static const struct nxp_flexio_child nxp_flexio_spi_child_##n = { \
 		.isr = spi_mcux_flexio_isr,				\
 		.user_data = (void *)DEVICE_DT_INST_GET(n),		\
 		.res = {						\
 			.shifter_index = flexio_spi_##n.shifterIndex,	\
 			.shifter_count = ARRAY_SIZE(flexio_spi_##n.shifterIndex), \
 			.timer_index = flexio_spi_##n.timerIndex,	\
 			.timer_count = ARRAY_SIZE(flexio_spi_##n.timerIndex) \
 		}							\
 	};								\
 									\
 	static const struct spi_mcux_flexio_config spi_mcux_flexio_config_##n = { \
 		.flexio_spi = &flexio_spi_##n,				\
 		.flexio_dev = DEVICE_DT_GET(DT_INST_PARENT(n)),		\
 		.pincfg = PINCTRL_DT_INST_DEV_CONFIG_GET(n),		\
 		.child = &nxp_flexio_spi_child_##n,			\
 	};								\
 									\
 	static struct spi_mcux_flexio_data spi_mcux_flexio_data_##n = {	\
 		SPI_CONTEXT_INIT_LOCK(spi_mcux_flexio_data_##n, ctx),	\
 		SPI_CONTEXT_INIT_SYNC(spi_mcux_flexio_data_##n, ctx),	\
 		SPI_CONTEXT_CS_GPIOS_INITIALIZE(DT_DRV_INST(n), ctx)	\
 	};								\
 									\
 	DEVICE_DT_INST_DEFINE(n, spi_mcux_init, NULL,			\
 				&spi_mcux_flexio_data_##n,		\
 				&spi_mcux_flexio_config_##n, POST_KERNEL, \
 				CONFIG_SPI_INIT_PRIORITY,		\
 				&spi_mcux_driver_api);			\

 DT_INST_FOREACH_STATUS_OKAY(SPI_MCUX_FLEXIO_SPI_INIT)
	/*
	* Copyright (c) 2024, STRIM, ALC
	* Copyright 2024 NXP
	*
	* SPDX-License-Identifier: Apache-2.0
	*/

	#define DT_DRV_COMPAT nxp_flexio_spi

	#include <errno.h>
	#include <zephyr/drivers/spi.h>
	#include <zephyr/drivers/clock_control.h>
	#include <fsl_flexio_spi.h>
	#include <zephyr/logging/log.h>
	#include <zephyr/drivers/pinctrl.h>
	#include <zephyr/drivers/misc/nxp_flexio/nxp_flexio.h>

	LOG_MODULE_REGISTER(spi_mcux_flexio_spi, CONFIG_SPI_LOG_LEVEL);

	#include "spi_context.h"


	struct spi_mcux_flexio_config {
	FLEXIO_SPI_Type *flexio_spi;
	const struct device *flexio_dev;
	const struct pinctrl_dev_config *pincfg;
	const struct nxp_flexio_child *child;
	};

	struct spi_mcux_flexio_data {
	const struct device *dev;
	flexio_spi_master_handle_t handle;
	struct spi_context ctx;
	size_t transfer_len;
	uint8_t transfer_flags;
	};


	static void spi_mcux_transfer_next_packet(const struct device *dev)
	{
	const struct spi_mcux_flexio_config *config = dev->config;
	struct spi_mcux_flexio_data *data = dev->data;
	struct spi_context *ctx = &data->ctx;
	flexio_spi_transfer_t transfer;
	status_t status;

	if ((ctx->tx_len == 0) && (ctx->rx_len == 0)) {
	/* nothing left to rx or tx, we're done! */
	spi_context_cs_control(&data->ctx, false);
	spi_context_complete(&data->ctx, dev, 0);
	return;
	}

	transfer.flags = kFLEXIO_SPI_csContinuous \| data->transfer_flags;

	if (ctx->tx_len == 0) {
	/* rx only, nothing to tx */
	transfer.txData = NULL;
	transfer.rxData = ctx->rx_buf;
	transfer.dataSize = ctx->rx_len;
	} else if (ctx->rx_len == 0) {
	/* tx only, nothing to rx */
	transfer.txData = (uint8_t *) ctx->tx_buf;
	transfer.rxData = NULL;
	transfer.dataSize = ctx->tx_len;
	} else if (ctx->tx_len == ctx->rx_len) {
	/* rx and tx are the same length */
	transfer.txData = (uint8_t *) ctx->tx_buf;
	transfer.rxData = ctx->rx_buf;
	transfer.dataSize = ctx->tx_len;
	} else if (ctx->tx_len > ctx->rx_len) {
	/* Break up the tx into multiple transfers so we don't have to
	* rx into a longer intermediate buffer. Leave chip select
	* active between transfers.
	*/
	transfer.txData = (uint8_t *) ctx->tx_buf;
	transfer.rxData = ctx->rx_buf;
	transfer.dataSize = ctx->rx_len;
	} else {
	/* Break up the rx into multiple transfers so we don't have to
	* tx from a longer intermediate buffer. Leave chip select
	* active between transfers.
	*/
	transfer.txData = (uint8_t *) ctx->tx_buf;
	transfer.rxData = ctx->rx_buf;
	transfer.dataSize = ctx->tx_len;
	}

	data->transfer_len = transfer.dataSize;

	status = FLEXIO_SPI_MasterTransferNonBlocking(config->flexio_spi, &data->handle,
	&transfer);
	if (status != kStatus_Success) {
	LOG_ERR("Transfer could not start");
	}
	}

	static int spi_mcux_flexio_isr(void *user_data)
	{
	const struct device dev = (const struct device )user_data;
	const struct spi_mcux_flexio_config *config = dev->config;
	struct spi_mcux_flexio_data *data = dev->data;

	#if defined(CONFIG_SOC_SERIES_KE1XZ)
	/* Wait until data transfer complete. */
	WAIT_FOR((0U == (FLEXIO_SPI_GetStatusFlags(config->flexio_spi)
	& (uint32_t)kFLEXIO_SPI_TxBufferEmptyFlag)), 100, NULL);
	#endif
	FLEXIO_SPI_MasterTransferHandleIRQ(config->flexio_spi, &data->handle);

	return 0;
	}

	static void spi_mcux_master_transfer_callback(FLEXIO_SPI_Type *flexio_spi,
	flexio_spi_master_handle_t handle, status_t status, void userData)
	{
	struct spi_mcux_flexio_data *data = userData;

	spi_context_update_tx(&data->ctx, 1, data->transfer_len);
	spi_context_update_rx(&data->ctx, 1, data->transfer_len);

	spi_mcux_transfer_next_packet(data->dev);
	}

	static void spi_flexio_master_init(FLEXIO_SPI_Type base, flexio_spi_master_config_t masterConfig,
	uint8_t pol, uint32_t srcClock_Hz)
	{
	assert(base != NULL);
	assert(masterConfig != NULL);

	flexio_shifter_config_t shifterConfig;
	flexio_timer_config_t timerConfig;
	uint32_t ctrlReg = 0;
	uint16_t timerDiv = 0;
	uint16_t timerCmp = 0;

	/* Clear the shifterConfig & timerConfig struct. */
	(void)memset(&shifterConfig, 0, sizeof(shifterConfig));
	(void)memset(&timerConfig, 0, sizeof(timerConfig));

	/* Configure FLEXIO SPI Master */
	ctrlReg = base->flexioBase->CTRL;
	ctrlReg &= ~(FLEXIO_CTRL_DOZEN_MASK \| FLEXIO_CTRL_DBGE_MASK \|
	FLEXIO_CTRL_FASTACC_MASK \| FLEXIO_CTRL_FLEXEN_MASK);
	ctrlReg \|= (FLEXIO_CTRL_DBGE(masterConfig->enableInDebug) \|
	FLEXIO_CTRL_FASTACC(masterConfig->enableFastAccess) \|
	FLEXIO_CTRL_FLEXEN(masterConfig->enableMaster));
	if (!masterConfig->enableInDoze) {
	ctrlReg \|= FLEXIO_CTRL_DOZEN_MASK;
	}

	base->flexioBase->CTRL = ctrlReg;

	/* Do hardware configuration. */
	/* 1. Configure the shifter 0 for tx. */
	shifterConfig.timerSelect = base->timerIndex[0];
	shifterConfig.pinConfig = kFLEXIO_PinConfigOutput;
	shifterConfig.pinSelect = base->SDOPinIndex;
	shifterConfig.pinPolarity = kFLEXIO_PinActiveHigh;
	shifterConfig.shifterMode = kFLEXIO_ShifterModeTransmit;
	shifterConfig.inputSource = kFLEXIO_ShifterInputFromPin;
	if (masterConfig->phase == kFLEXIO_SPI_ClockPhaseFirstEdge) {
	shifterConfig.timerPolarity = kFLEXIO_ShifterTimerPolarityOnNegitive;
	shifterConfig.shifterStop = kFLEXIO_ShifterStopBitDisable;
	shifterConfig.shifterStart = kFLEXIO_ShifterStartBitDisabledLoadDataOnEnable;
	} else {
	shifterConfig.timerPolarity = kFLEXIO_ShifterTimerPolarityOnPositive;
	shifterConfig.shifterStop = kFLEXIO_ShifterStopBitLow;
	shifterConfig.shifterStart = kFLEXIO_ShifterStartBitDisabledLoadDataOnShift;
	}

	FLEXIO_SetShifterConfig(base->flexioBase, base->shifterIndex[0], &shifterConfig);

	/* 2. Configure the shifter 1 for rx. */
	shifterConfig.timerSelect = base->timerIndex[0];
	shifterConfig.pinConfig = kFLEXIO_PinConfigOutputDisabled;
	shifterConfig.pinSelect = base->SDIPinIndex;
	shifterConfig.pinPolarity = kFLEXIO_PinActiveHigh;
	shifterConfig.shifterMode = kFLEXIO_ShifterModeReceive;
	shifterConfig.inputSource = kFLEXIO_ShifterInputFromPin;
	shifterConfig.shifterStop = kFLEXIO_ShifterStopBitDisable;
	shifterConfig.shifterStart = kFLEXIO_ShifterStartBitDisabledLoadDataOnEnable;
	if (masterConfig->phase == kFLEXIO_SPI_ClockPhaseFirstEdge) {
	shifterConfig.timerPolarity = kFLEXIO_ShifterTimerPolarityOnPositive;
	} else {
	shifterConfig.timerPolarity = kFLEXIO_ShifterTimerPolarityOnNegitive;
	}

	FLEXIO_SetShifterConfig(base->flexioBase, base->shifterIndex[1], &shifterConfig);

	/3. Configure the timer 0 for SCK. /
	timerConfig.triggerSelect = FLEXIO_TIMER_TRIGGER_SEL_SHIFTnSTAT(base->shifterIndex[0]);
	timerConfig.triggerPolarity = kFLEXIO_TimerTriggerPolarityActiveLow;
	timerConfig.triggerSource = kFLEXIO_TimerTriggerSourceInternal;
	timerConfig.pinConfig = kFLEXIO_PinConfigOutput;
	timerConfig.pinSelect = base->SCKPinIndex;
	timerConfig.pinPolarity = pol ? kFLEXIO_PinActiveLow : kFLEXIO_PinActiveHigh;
	timerConfig.timerMode = kFLEXIO_TimerModeDual8BitBaudBit;
	timerConfig.timerOutput = kFLEXIO_TimerOutputZeroNotAffectedByReset;
	timerConfig.timerDecrement = kFLEXIO_TimerDecSrcOnFlexIOClockShiftTimerOutput;
	timerConfig.timerReset = kFLEXIO_TimerResetNever;
	timerConfig.timerDisable = kFLEXIO_TimerDisableOnTimerCompare;
	timerConfig.timerEnable = kFLEXIO_TimerEnableOnTriggerHigh;
	timerConfig.timerStop = kFLEXIO_TimerStopBitEnableOnTimerDisable;
	timerConfig.timerStart = kFLEXIO_TimerStartBitEnabled;
	/* Low 8-bits are used to configure baudrate. */
	timerDiv = (uint16_t)(srcClock_Hz / masterConfig->baudRate_Bps);
	timerDiv = timerDiv / 2U - 1U;
	/* High 8-bits are used to configure shift clock edges(transfer width). */
	timerCmp = ((uint16_t)masterConfig->dataMode * 2U - 1U) << 8U;
	timerCmp \|= timerDiv;

	timerConfig.timerCompare = timerCmp;

	FLEXIO_SetTimerConfig(base->flexioBase, base->timerIndex[0], &timerConfig);
	}

	static int spi_mcux_flexio_configure(const struct device *dev,
	const struct spi_config *spi_cfg)
	{
	const struct spi_mcux_flexio_config *config = dev->config;
	struct spi_mcux_flexio_data *data = dev->data;

	flexio_spi_master_config_t master_config;
	uint32_t clock_freq;
	uint32_t word_size;

	if (spi_context_configured(&data->ctx, spi_cfg)) {
	/* This configuration is already in use */
	return 0;
	}

	if (spi_cfg->operation & SPI_HALF_DUPLEX) {
	LOG_ERR("Half-duplex not supported");
	return -ENOTSUP;
	}

	if (SPI_OP_MODE_GET(spi_cfg->operation) != SPI_OP_MODE_MASTER) {
	LOG_ERR("Mode Slave not supported");
	return -ENOTSUP;
	}

	FLEXIO_SPI_MasterGetDefaultConfig(&master_config);

	word_size = SPI_WORD_SIZE_GET(spi_cfg->operation);
	if ((word_size != 8) && (word_size != 16) && (word_size != 32)) {
	LOG_ERR("Word size %d must be 8, 16 or 32", word_size);
	return -EINVAL;
	}
	master_config.dataMode = word_size;

	if (spi_cfg->operation & SPI_TRANSFER_LSB) {
	if (word_size == 8) {
	data->transfer_flags = kFLEXIO_SPI_8bitLsb;
	} else if (word_size == 16) {
	data->transfer_flags = kFLEXIO_SPI_16bitLsb;
	} else {
	data->transfer_flags = kFLEXIO_SPI_32bitLsb;
	}
	} else {
	if (word_size == 8) {
	data->transfer_flags = kFLEXIO_SPI_8bitMsb;
	} else if (word_size == 16) {
	data->transfer_flags = kFLEXIO_SPI_16bitMsb;
	} else {
	data->transfer_flags = kFLEXIO_SPI_32bitMsb;
	}
	}

	if (nxp_flexio_get_rate(config->flexio_dev, &clock_freq)) {
	return -EINVAL;
	}

	master_config.phase =
	(SPI_MODE_GET(spi_cfg->operation) & SPI_MODE_CPHA)
	? kFLEXIO_SPI_ClockPhaseSecondEdge
	: kFLEXIO_SPI_ClockPhaseFirstEdge;

	master_config.baudRate_Bps = spi_cfg->frequency;
	spi_flexio_master_init(config->flexio_spi, &master_config,
	(SPI_MODE_GET(spi_cfg->operation) & SPI_MODE_CPOL), clock_freq);

	FLEXIO_SPI_MasterTransferCreateHandle(config->flexio_spi, &data->handle,
	spi_mcux_master_transfer_callback,
	data);
	/* No SetDummyData() for FlexIO_SPI */

	data->ctx.config = spi_cfg;

	return 0;
	}


	static int transceive(const struct device *dev,
	const struct spi_config *spi_cfg,
	const struct spi_buf_set *tx_bufs,
	const struct spi_buf_set *rx_bufs,
	bool asynchronous,
	spi_callback_t cb,
	void *userdata)
	{
	const struct spi_mcux_flexio_config *config = dev->config;
	struct spi_mcux_flexio_data *data = dev->data;
	int ret;

	spi_context_lock(&data->ctx, asynchronous, cb, userdata, spi_cfg);

	nxp_flexio_lock(config->flexio_dev);
	ret = spi_mcux_flexio_configure(dev, spi_cfg);
	nxp_flexio_unlock(config->flexio_dev);
	if (ret) {
	goto out;
	}

	spi_context_buffers_setup(&data->ctx, tx_bufs, rx_bufs, 1);

	spi_context_cs_control(&data->ctx, true);

	nxp_flexio_lock(config->flexio_dev);
	nxp_flexio_irq_disable(config->flexio_dev);

	spi_mcux_transfer_next_packet(dev);

	nxp_flexio_irq_enable(config->flexio_dev);
	nxp_flexio_unlock(config->flexio_dev);

	ret = spi_context_wait_for_completion(&data->ctx);
	out:
	spi_context_release(&data->ctx, ret);

	return ret;
	}

	static int spi_mcux_transceive(const struct device *dev,
	const struct spi_config *spi_cfg,
	const struct spi_buf_set *tx_bufs,
	const struct spi_buf_set *rx_bufs)
	{
	return transceive(dev, spi_cfg, tx_bufs, rx_bufs, false, NULL, NULL);
	}

	#ifdef CONFIG_SPI_ASYNC
	static int spi_mcux_transceive_async(const struct device *dev,
	const struct spi_config *spi_cfg,
	const struct spi_buf_set *tx_bufs,
	const struct spi_buf_set *rx_bufs,
	spi_callback_t cb,
	void *userdata)
	{
	return transceive(dev, spi_cfg, tx_bufs, rx_bufs, true, cb, userdata);
	}
	#endif /* CONFIG_SPI_ASYNC */

	static int spi_mcux_release(const struct device *dev,
	const struct spi_config *spi_cfg)
	{
	struct spi_mcux_flexio_data *data = dev->data;

	spi_context_unlock_unconditionally(&data->ctx);

	return 0;
	}

	static int spi_mcux_init(const struct device *dev)
	{
	const struct spi_mcux_flexio_config *config = dev->config;
	struct spi_mcux_flexio_data *data = dev->data;
	int err;

	err = nxp_flexio_child_attach(config->flexio_dev, config->child);
	if (err < 0) {
	return err;
	}

	err = spi_context_cs_configure_all(&data->ctx);
	if (err < 0) {
	return err;
	}

	spi_context_unlock_unconditionally(&data->ctx);

	data->dev = dev;

	/* TODO: DMA */

	err = pinctrl_apply_state(config->pincfg, PINCTRL_STATE_DEFAULT);
	if (err) {
	return err;
	}

	spi_context_unlock_unconditionally(&data->ctx);

	return 0;
	}

	static const struct spi_driver_api spi_mcux_driver_api = {
	.transceive = spi_mcux_transceive,
	#ifdef CONFIG_SPI_ASYNC
	.transceive_async = spi_mcux_transceive_async,
	#endif
	.release = spi_mcux_release,
	};

	#define SPI_MCUX_FLEXIO_SPI_INIT(n) \
	PINCTRL_DT_INST_DEFINE(n); \
	\
	static FLEXIO_SPI_Type flexio_spi_##n = { \
	.flexioBase = (FLEXIO_Type *)DT_REG_ADDR(DT_INST_PARENT(n)), \
	.SDOPinIndex = DT_INST_PROP(n, sdo_pin), \
	.SDIPinIndex = DT_INST_PROP(n, sdi_pin), \
	.SCKPinIndex = DT_INST_PROP(n, sck_pin), \
	}; \
	\
	static const struct nxp_flexio_child nxp_flexio_spi_child_##n = { \
	.isr = spi_mcux_flexio_isr, \
	.user_data = (void *)DEVICE_DT_INST_GET(n), \
	.res = { \
	.shifter_index = flexio_spi_##n.shifterIndex, \
	.shifter_count = ARRAY_SIZE(flexio_spi_##n.shifterIndex), \
	.timer_index = flexio_spi_##n.timerIndex, \
	.timer_count = ARRAY_SIZE(flexio_spi_##n.timerIndex) \
	} \
	}; \
	\
	static const struct spi_mcux_flexio_config spi_mcux_flexio_config_##n = { \
	.flexio_spi = &flexio_spi_##n, \
	.flexio_dev = DEVICE_DT_GET(DT_INST_PARENT(n)), \
	.pincfg = PINCTRL_DT_INST_DEV_CONFIG_GET(n), \
	.child = &nxp_flexio_spi_child_##n, \
	}; \
	\
	static struct spi_mcux_flexio_data spi_mcux_flexio_data_##n = { \
	SPI_CONTEXT_INIT_LOCK(spi_mcux_flexio_data_##n, ctx), \
	SPI_CONTEXT_INIT_SYNC(spi_mcux_flexio_data_##n, ctx), \
	SPI_CONTEXT_CS_GPIOS_INITIALIZE(DT_DRV_INST(n), ctx) \
	}; \
	\
	DEVICE_DT_INST_DEFINE(n, spi_mcux_init, NULL, \
	&spi_mcux_flexio_data_##n, \
	&spi_mcux_flexio_config_##n, POST_KERNEL, \
	CONFIG_SPI_INIT_PRIORITY, \
	&spi_mcux_driver_api); \

	DT_INST_FOREACH_STATUS_OKAY(SPI_MCUX_FLEXIO_SPI_INIT)