rt-thread-official/bsp/imxrt1052-evk/Libraries/drivers/fsl_lpi2c.c

/*
 * The Clear BSD License
 * Copyright (c) 2015, Freescale Semiconductor, Inc.
 * Copyright 2016-2017 NXP
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted (subject to the limitations in the disclaimer below) provided
 *  that the following conditions are met:
 *
 * o Redistributions of source code must retain the above copyright notice, this list
 *   of conditions and the following disclaimer.
 *
 * o Redistributions in binary form must reproduce the above copyright notice, this
 *   list of conditions and the following disclaimer in the documentation and/or
 *   other materials provided with the distribution.
 *
 * o Neither the name of the copyright holder nor the names of its
 *   contributors may be used to endorse or promote products derived from this
 *   software without specific prior written permission.
 *
 * NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE GRANTED BY THIS LICENSE.
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "fsl_lpi2c.h"
#include <stdlib.h>
#include <string.h>

/*******************************************************************************
 * Definitions
 ******************************************************************************/

/* Component ID definition, used by tools. */
#ifndef FSL_COMPONENT_ID
#define FSL_COMPONENT_ID "platform.drivers.lpi2c"
#endif

/*! @brief Common sets of flags used by the driver. */
enum _lpi2c_flag_constants
{
    /*! All flags which are cleared by the driver upon starting a transfer. */
    kMasterClearFlags = kLPI2C_MasterEndOfPacketFlag | kLPI2C_MasterStopDetectFlag | kLPI2C_MasterNackDetectFlag |
                        kLPI2C_MasterArbitrationLostFlag | kLPI2C_MasterFifoErrFlag | kLPI2C_MasterPinLowTimeoutFlag |
                        kLPI2C_MasterDataMatchFlag,

    /*! IRQ sources enabled by the non-blocking transactional API. */
    kMasterIrqFlags = kLPI2C_MasterArbitrationLostFlag | kLPI2C_MasterTxReadyFlag | kLPI2C_MasterRxReadyFlag |
                      kLPI2C_MasterStopDetectFlag | kLPI2C_MasterNackDetectFlag | kLPI2C_MasterPinLowTimeoutFlag |
                      kLPI2C_MasterFifoErrFlag,

    /*! Errors to check for. */
    kMasterErrorFlags = kLPI2C_MasterNackDetectFlag | kLPI2C_MasterArbitrationLostFlag | kLPI2C_MasterFifoErrFlag |
                        kLPI2C_MasterPinLowTimeoutFlag,

    /*! All flags which are cleared by the driver upon starting a transfer. */
    kSlaveClearFlags = kLPI2C_SlaveRepeatedStartDetectFlag | kLPI2C_SlaveStopDetectFlag | kLPI2C_SlaveBitErrFlag |
                       kLPI2C_SlaveFifoErrFlag,

    /*! IRQ sources enabled by the non-blocking transactional API. */
    kSlaveIrqFlags = kLPI2C_SlaveTxReadyFlag | kLPI2C_SlaveRxReadyFlag | kLPI2C_SlaveStopDetectFlag |
                     kLPI2C_SlaveRepeatedStartDetectFlag | kLPI2C_SlaveFifoErrFlag | kLPI2C_SlaveBitErrFlag |
                     kLPI2C_SlaveTransmitAckFlag | kLPI2C_SlaveAddressValidFlag,

    /*! Errors to check for. */
    kSlaveErrorFlags = kLPI2C_SlaveFifoErrFlag | kLPI2C_SlaveBitErrFlag,
};

/* ! @brief LPI2C master fifo commands. */
enum _lpi2c_master_fifo_cmd
{
    kTxDataCmd = LPI2C_MTDR_CMD(0x0U), /*!< Transmit DATA[7:0] */
    kRxDataCmd = LPI2C_MTDR_CMD(0X1U), /*!< Receive (DATA[7:0] + 1) bytes */
    kStopCmd = LPI2C_MTDR_CMD(0x2U),   /*!< Generate STOP condition */
    kStartCmd = LPI2C_MTDR_CMD(0x4U),  /*!< Generate(repeated) START and transmit address in DATA[[7:0] */
};

/*!
 * @brief Default watermark values.
 *
 * The default watermarks are set to zero.
 */
enum _lpi2c_default_watermarks
{
    kDefaultTxWatermark = 0,
    kDefaultRxWatermark = 0,
};

/*! @brief States for the state machine used by transactional APIs. */
enum _lpi2c_transfer_states
{
    kIdleState = 0,
    kSendCommandState,
    kIssueReadCommandState,
    kTransferDataState,
    kStopState,
    kWaitForCompletionState,
};

/*! @brief Typedef for master interrupt handler. */
typedef void (*lpi2c_master_isr_t)(LPI2C_Type *base, lpi2c_master_handle_t *handle);

/*! @brief Typedef for slave interrupt handler. */
typedef void (*lpi2c_slave_isr_t)(LPI2C_Type *base, lpi2c_slave_handle_t *handle);

/*******************************************************************************
 * Prototypes
 ******************************************************************************/

/* Not static so it can be used from fsl_lpi2c_edma.c. */
uint32_t LPI2C_GetInstance(LPI2C_Type *base);

static uint32_t LPI2C_GetCyclesForWidth(uint32_t sourceClock_Hz,
                                        uint32_t width_ns,
                                        uint32_t maxCycles,
                                        uint32_t prescaler);

static status_t LPI2C_MasterWaitForTxReady(LPI2C_Type *base);

static status_t LPI2C_RunTransferStateMachine(LPI2C_Type *base, lpi2c_master_handle_t *handle, bool *isDone);

static void LPI2C_InitTransferStateMachine(lpi2c_master_handle_t *handle);

static status_t LPI2C_SlaveCheckAndClearError(LPI2C_Type *base, uint32_t flags);

static void LPI2C_CommonIRQHandler(LPI2C_Type *base, uint32_t instance);

/*******************************************************************************
 * Variables
 ******************************************************************************/

/*! @brief Array to map LPI2C instance number to base pointer. */
static LPI2C_Type *const kLpi2cBases[] = LPI2C_BASE_PTRS;

/*! @brief Array to map LPI2C instance number to IRQ number. */
static IRQn_Type const kLpi2cIrqs[] = LPI2C_IRQS;

#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
/*! @brief Array to map LPI2C instance number to clock gate enum. */
static clock_ip_name_t const kLpi2cClocks[] = LPI2C_CLOCKS;

#if defined(LPI2C_PERIPH_CLOCKS)
/*! @brief Array to map LPI2C instance number to pheripheral clock gate enum. */
static const clock_ip_name_t kLpi2cPeriphClocks[] = LPI2C_PERIPH_CLOCKS;
#endif

#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */

/*! @brief Pointer to master IRQ handler for each instance. */
static lpi2c_master_isr_t s_lpi2cMasterIsr;

/*! @brief Pointers to master handles for each instance. */
static lpi2c_master_handle_t *s_lpi2cMasterHandle[ARRAY_SIZE(kLpi2cBases)];

/*! @brief Pointer to slave IRQ handler for each instance. */
static lpi2c_slave_isr_t s_lpi2cSlaveIsr;

/*! @brief Pointers to slave handles for each instance. */
static lpi2c_slave_handle_t *s_lpi2cSlaveHandle[ARRAY_SIZE(kLpi2cBases)];

/*******************************************************************************
 * Code
 ******************************************************************************/

/*!
 * @brief Returns an instance number given a base address.
 *
 * If an invalid base address is passed, debug builds will assert. Release builds will just return
 * instance number 0.
 *
 * @param base The LPI2C peripheral base address.
 * @return LPI2C instance number starting from 0.
 */
uint32_t LPI2C_GetInstance(LPI2C_Type *base)
{
    uint32_t instance;
    for (instance = 0; instance < ARRAY_SIZE(kLpi2cBases); ++instance)
    {
        if (kLpi2cBases[instance] == base)
        {
            return instance;
        }
    }

    assert(false);
    return 0;
}

/*!
 * @brief Computes a cycle count for a given time in nanoseconds.
 * @param sourceClock_Hz LPI2C functional clock frequency in Hertz.
 * @param width_ns Desired with in nanoseconds.
 * @param maxCycles Maximum cycle count, determined by the number of bits wide the cycle count field is.
 * @param prescaler LPI2C prescaler setting. Pass 1 if the prescaler should not be used, as for slave glitch widths.
 */
static uint32_t LPI2C_GetCyclesForWidth(uint32_t sourceClock_Hz,
                                        uint32_t width_ns,
                                        uint32_t maxCycles,
                                        uint32_t prescaler)
{
    assert(sourceClock_Hz > 0);
    assert(prescaler > 0);

    uint32_t busCycle_ns = 1000000 / (sourceClock_Hz / prescaler / 1000);
    uint32_t cycles = 0;

    /* Search for the cycle count just below the desired glitch width. */
    while ((((cycles + 1) * busCycle_ns) < width_ns) && (cycles + 1 < maxCycles))
    {
        ++cycles;
    }

    /* If we end up with zero cycles, then set the filter to a single cycle unless the */
    /* bus clock is greater than 10x the desired glitch width. */
    if ((cycles == 0) && (busCycle_ns <= (width_ns * 10)))
    {
        cycles = 1;
    }

    return cycles;
}

/*!
 * @brief Convert provided flags to status code, and clear any errors if present.
 * @param base The LPI2C peripheral base address.
 * @param status Current status flags value that will be checked.
 * @retval #kStatus_Success
 * @retval #kStatus_LPI2C_PinLowTimeout
 * @retval #kStatus_LPI2C_ArbitrationLost
 * @retval #kStatus_LPI2C_Nak
 * @retval #kStatus_LPI2C_FifoError
 */
status_t LPI2C_MasterCheckAndClearError(LPI2C_Type *base, uint32_t status)
{
    status_t result = kStatus_Success;

    /* Check for error. These errors cause a stop to automatically be sent. We must */
    /* clear the errors before a new transfer can start. */
    status &= kMasterErrorFlags;
    if (status)
    {
        /* Select the correct error code. Ordered by severity, with bus issues first. */
        if (status & kLPI2C_MasterPinLowTimeoutFlag)
        {
            result = kStatus_LPI2C_PinLowTimeout;
        }
        else if (status & kLPI2C_MasterArbitrationLostFlag)
        {
            result = kStatus_LPI2C_ArbitrationLost;
        }
        else if (status & kLPI2C_MasterNackDetectFlag)
        {
            result = kStatus_LPI2C_Nak;
        }
        else if (status & kLPI2C_MasterFifoErrFlag)
        {
            result = kStatus_LPI2C_FifoError;
        }
        else
        {
            assert(false);
        }

        /* Clear the flags. */
        LPI2C_MasterClearStatusFlags(base, status);

        /* Reset fifos. These flags clear automatically. */
        base->MCR |= LPI2C_MCR_RRF_MASK | LPI2C_MCR_RTF_MASK;
    }

    return result;
}

/*!
 * @brief Wait until there is room in the tx fifo.
 * @param base The LPI2C peripheral base address.
 * @retval #kStatus_Success
 * @retval #kStatus_LPI2C_PinLowTimeout
 * @retval #kStatus_LPI2C_ArbitrationLost
 * @retval #kStatus_LPI2C_Nak
 * @retval #kStatus_LPI2C_FifoError
 */
static status_t LPI2C_MasterWaitForTxReady(LPI2C_Type *base)
{
    uint32_t status;
    size_t txCount;
    size_t txFifoSize = FSL_FEATURE_LPI2C_FIFO_SIZEn(base);

#if LPI2C_WAIT_TIMEOUT
    uint32_t waitTimes = LPI2C_WAIT_TIMEOUT;
#endif
    do
    {
        status_t result;

        /* Get the number of words in the tx fifo and compute empty slots. */
        LPI2C_MasterGetFifoCounts(base, NULL, &txCount);
        txCount = txFifoSize - txCount;

        /* Check for error flags. */
        status = LPI2C_MasterGetStatusFlags(base);
        result = LPI2C_MasterCheckAndClearError(base, status);
        if (result)
        {
            return result;
        }
#if LPI2C_WAIT_TIMEOUT
    } while ((!txCount) && (--waitTimes));

    if (waitTimes == 0)
    {
        return kStatus_LPI2C_Timeout;
    }
#else
    } while (!txCount);
#endif

    return kStatus_Success;
}

/*!
 * @brief Make sure the bus isn't already busy.
 *
 * A busy bus is allowed if we are the one driving it.
 *
 * @param base The LPI2C peripheral base address.
 * @retval #kStatus_Success
 * @retval #kStatus_LPI2C_Busy
 */
status_t LPI2C_CheckForBusyBus(LPI2C_Type *base)
{
    uint32_t status = LPI2C_MasterGetStatusFlags(base);
    if ((status & kLPI2C_MasterBusBusyFlag) && (!(status & kLPI2C_MasterBusyFlag)))
    {
        return kStatus_LPI2C_Busy;
    }

    return kStatus_Success;
}

void LPI2C_MasterGetDefaultConfig(lpi2c_master_config_t *masterConfig)
{
    masterConfig->enableMaster = true;
    masterConfig->debugEnable = false;
    masterConfig->enableDoze = true;
    masterConfig->ignoreAck = false;
    masterConfig->pinConfig = kLPI2C_2PinOpenDrain;
    masterConfig->baudRate_Hz = 100000U;
    masterConfig->busIdleTimeout_ns = 0;
    masterConfig->pinLowTimeout_ns = 0;
    masterConfig->sdaGlitchFilterWidth_ns = 0;
    masterConfig->sclGlitchFilterWidth_ns = 0;
    masterConfig->hostRequest.enable = false;
    masterConfig->hostRequest.source = kLPI2C_HostRequestExternalPin;
    masterConfig->hostRequest.polarity = kLPI2C_HostRequestPinActiveHigh;
}

void LPI2C_MasterInit(LPI2C_Type *base, const lpi2c_master_config_t *masterConfig, uint32_t sourceClock_Hz)
{
    uint32_t prescaler;
    uint32_t cycles;
    uint32_t cfgr2;
    uint32_t value;

#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)

    uint32_t instance = LPI2C_GetInstance(base);

    /* Ungate the clock. */
    CLOCK_EnableClock(kLpi2cClocks[instance]);
#if defined(LPI2C_PERIPH_CLOCKS)
    /* Ungate the functional clock in initialize function. */
    CLOCK_EnableClock(kLpi2cPeriphClocks[instance]);
#endif

#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */

    /* Reset peripheral before configuring it. */
    LPI2C_MasterReset(base);

    /* Doze bit: 0 is enable, 1 is disable */
    base->MCR = LPI2C_MCR_DBGEN(masterConfig->debugEnable) | LPI2C_MCR_DOZEN(!(masterConfig->enableDoze));

    /* host request */
    value = base->MCFGR0;
    value &= (~(LPI2C_MCFGR0_HREN_MASK | LPI2C_MCFGR0_HRPOL_MASK | LPI2C_MCFGR0_HRSEL_MASK));
    value |= LPI2C_MCFGR0_HREN(masterConfig->hostRequest.enable) |
             LPI2C_MCFGR0_HRPOL(masterConfig->hostRequest.polarity) |
             LPI2C_MCFGR0_HRSEL(masterConfig->hostRequest.source);
    base->MCFGR0 = value;

    /* pin config and ignore ack */
    value = base->MCFGR1;
    value &= ~(LPI2C_MCFGR1_PINCFG_MASK | LPI2C_MCFGR1_IGNACK_MASK);
    value |= LPI2C_MCFGR1_PINCFG(masterConfig->pinConfig);
    value |= LPI2C_MCFGR1_IGNACK(masterConfig->ignoreAck);
    base->MCFGR1 = value;

    LPI2C_MasterSetWatermarks(base, kDefaultTxWatermark, kDefaultRxWatermark);

    LPI2C_MasterSetBaudRate(base, sourceClock_Hz, masterConfig->baudRate_Hz);

    /* Configure glitch filters and bus idle and pin low timeouts. */
    prescaler = (base->MCFGR1 & LPI2C_MCFGR1_PRESCALE_MASK) >> LPI2C_MCFGR1_PRESCALE_SHIFT;
    cfgr2 = base->MCFGR2;
    if (masterConfig->busIdleTimeout_ns)
    {
        cycles = LPI2C_GetCyclesForWidth(sourceClock_Hz, masterConfig->busIdleTimeout_ns,
                                         (LPI2C_MCFGR2_BUSIDLE_MASK >> LPI2C_MCFGR2_BUSIDLE_SHIFT), prescaler);
        cfgr2 &= ~LPI2C_MCFGR2_BUSIDLE_MASK;
        cfgr2 |= LPI2C_MCFGR2_BUSIDLE(cycles);
    }
    if (masterConfig->sdaGlitchFilterWidth_ns)
    {
        cycles = LPI2C_GetCyclesForWidth(sourceClock_Hz, masterConfig->sdaGlitchFilterWidth_ns,
                                         (LPI2C_MCFGR2_FILTSDA_MASK >> LPI2C_MCFGR2_FILTSDA_SHIFT), 1);
        cfgr2 &= ~LPI2C_MCFGR2_FILTSDA_MASK;
        cfgr2 |= LPI2C_MCFGR2_FILTSDA(cycles);
    }
    if (masterConfig->sclGlitchFilterWidth_ns)
    {
        cycles = LPI2C_GetCyclesForWidth(sourceClock_Hz, masterConfig->sclGlitchFilterWidth_ns,
                                         (LPI2C_MCFGR2_FILTSCL_MASK >> LPI2C_MCFGR2_FILTSCL_SHIFT), 1);
        cfgr2 &= ~LPI2C_MCFGR2_FILTSCL_MASK;
        cfgr2 |= LPI2C_MCFGR2_FILTSCL(cycles);
    }
    base->MCFGR2 = cfgr2;
    if (masterConfig->pinLowTimeout_ns)
    {
        cycles = LPI2C_GetCyclesForWidth(sourceClock_Hz, masterConfig->pinLowTimeout_ns / 256,
                                         (LPI2C_MCFGR2_BUSIDLE_MASK >> LPI2C_MCFGR2_BUSIDLE_SHIFT), prescaler);
        base->MCFGR3 = (base->MCFGR3 & ~LPI2C_MCFGR3_PINLOW_MASK) | LPI2C_MCFGR3_PINLOW(cycles);
    }

    LPI2C_MasterEnable(base, masterConfig->enableMaster);
}

void LPI2C_MasterDeinit(LPI2C_Type *base)
{
    /* Restore to reset state. */
    LPI2C_MasterReset(base);

#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)

    uint32_t instance = LPI2C_GetInstance(base);

    /* Gate clock. */
    CLOCK_DisableClock(kLpi2cClocks[instance]);
#if defined(LPI2C_PERIPH_CLOCKS)
    /* Gate the functional clock. */
    CLOCK_DisableClock(kLpi2cPeriphClocks[instance]);
#endif

#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */
}

void LPI2C_MasterConfigureDataMatch(LPI2C_Type *base, const lpi2c_data_match_config_t *config)
{
    /* Disable master mode. */
    bool wasEnabled = (base->MCR & LPI2C_MCR_MEN_MASK) >> LPI2C_MCR_MEN_SHIFT;
    LPI2C_MasterEnable(base, false);

    base->MCFGR1 = (base->MCFGR1 & ~LPI2C_MCFGR1_MATCFG_MASK) | LPI2C_MCFGR1_MATCFG(config->matchMode);
    base->MCFGR0 = (base->MCFGR0 & ~LPI2C_MCFGR0_RDMO_MASK) | LPI2C_MCFGR0_RDMO(config->rxDataMatchOnly);
    base->MDMR = LPI2C_MDMR_MATCH0(config->match0) | LPI2C_MDMR_MATCH1(config->match1);

    /* Restore master mode. */
    if (wasEnabled)
    {
        LPI2C_MasterEnable(base, true);
    }
}

void LPI2C_MasterSetBaudRate(LPI2C_Type *base, uint32_t sourceClock_Hz, uint32_t baudRate_Hz)
{
    uint32_t prescale = 0;
    uint32_t bestPre = 0;
    uint32_t bestClkHi = 0;
    uint32_t absError = 0;
    uint32_t bestError = 0xffffffffu;
    uint32_t value;
    uint32_t clkHiCycle;
    uint32_t computedRate;
    int i;
    bool wasEnabled;

    /* Disable master mode. */
    wasEnabled = (base->MCR & LPI2C_MCR_MEN_MASK) >> LPI2C_MCR_MEN_SHIFT;
    LPI2C_MasterEnable(base, false);

    /* Baud rate = (sourceClock_Hz/2^prescale)/(CLKLO+1+CLKHI+1 + ROUNDDOWN((2+FILTSCL)/2^prescale) */
    /* Assume CLKLO = 2*CLKHI, SETHOLD = CLKHI, DATAVD = CLKHI/2. */
    for (prescale = 1; (prescale <= 128) && (bestError != 0); prescale = 2 * prescale)
    {
        for (clkHiCycle = 1; clkHiCycle < 32; clkHiCycle++)
        {
            if (clkHiCycle == 1)
            {
                computedRate = (sourceClock_Hz / prescale) / (1 + 3 + 2 + 2 / prescale);
            }
            else
            {
                computedRate = (sourceClock_Hz / prescale) / (3 * clkHiCycle + 2 + 2 / prescale);
            }

            absError = baudRate_Hz > computedRate ? baudRate_Hz - computedRate : computedRate - baudRate_Hz;

            if (absError < bestError)
            {
                bestPre = prescale;
                bestClkHi = clkHiCycle;
                bestError = absError;

                /* If the error is 0, then we can stop searching because we won't find a better match. */
                if (absError == 0)
                {
                    break;
                }
            }
        }
    }

    /* Standard, fast, fast mode plus and ultra-fast transfers. */
    value = LPI2C_MCCR0_CLKHI(bestClkHi);

    if (bestClkHi < 2)
    {
        value |= LPI2C_MCCR0_CLKLO(3) | LPI2C_MCCR0_SETHOLD(2) | LPI2C_MCCR0_DATAVD(1);
    }
    else
    {
        value |= LPI2C_MCCR0_CLKLO(2 * bestClkHi) | LPI2C_MCCR0_SETHOLD(bestClkHi) | LPI2C_MCCR0_DATAVD(bestClkHi / 2);
    }

    base->MCCR0 = value;

    for (i = 0; i < 8; i++)
    {
        if (bestPre == (1U << i))
        {
            bestPre = i;
            break;
        }
    }
    base->MCFGR1 = (base->MCFGR1 & ~LPI2C_MCFGR1_PRESCALE_MASK) | LPI2C_MCFGR1_PRESCALE(bestPre);

    /* Restore master mode. */
    if (wasEnabled)
    {
        LPI2C_MasterEnable(base, true);
    }
}

status_t LPI2C_MasterStart(LPI2C_Type *base, uint8_t address, lpi2c_direction_t dir)
{
    /* Return an error if the bus is already in use not by us. */
    status_t result = LPI2C_CheckForBusyBus(base);
    if (result)
    {
        return result;
    }

    /* Clear all flags. */
    LPI2C_MasterClearStatusFlags(base, kMasterClearFlags);

    /* Turn off auto-stop option. */
    base->MCFGR1 &= ~LPI2C_MCFGR1_AUTOSTOP_MASK;

    /* Wait until there is room in the fifo. */
    result = LPI2C_MasterWaitForTxReady(base);
    if (result)
    {
        return result;
    }

    /* Issue start command. */
    base->MTDR = kStartCmd | (((uint32_t)address << 1U) | (uint32_t)dir);

    return kStatus_Success;
}

status_t LPI2C_MasterStop(LPI2C_Type *base)
{
    /* Wait until there is room in the fifo. */
    status_t result = LPI2C_MasterWaitForTxReady(base);
    if (result)
    {
        return result;
    }

    /* Send the STOP signal */
    base->MTDR = kStopCmd;

/* Wait for the stop detected flag to set, indicating the transfer has completed on the bus. */
/* Also check for errors while waiting. */
#if LPI2C_WAIT_TIMEOUT
    uint32_t waitTimes = LPI2C_WAIT_TIMEOUT;
#endif

#if LPI2C_WAIT_TIMEOUT
    while ((result == kStatus_Success) && (--waitTimes))
#else
    while (result == kStatus_Success)
#endif
    {
        uint32_t status = LPI2C_MasterGetStatusFlags(base);

        /* Check for error flags. */
        result = LPI2C_MasterCheckAndClearError(base, status);

        /* Check if the stop was sent successfully. */
        if (status & kLPI2C_MasterStopDetectFlag)
        {
            LPI2C_MasterClearStatusFlags(base, kLPI2C_MasterStopDetectFlag);
            break;
        }
    }

#if LPI2C_WAIT_TIMEOUT
    if (waitTimes == 0)
    {
        return kStatus_LPI2C_Timeout;
    }
#endif

    return result;
}

status_t LPI2C_MasterReceive(LPI2C_Type *base, void *rxBuff, size_t rxSize)
{
    status_t result;
    uint8_t *buf;

    assert(rxBuff);

    /* Handle empty read. */
    if (!rxSize)
    {
        return kStatus_Success;
    }

    /* Wait until there is room in the command fifo. */
    result = LPI2C_MasterWaitForTxReady(base);
    if (result)
    {
        return result;
    }

    /* Issue command to receive data. */
    base->MTDR = kRxDataCmd | LPI2C_MTDR_DATA(rxSize - 1);

#if LPI2C_WAIT_TIMEOUT
    uint32_t waitTimes = LPI2C_WAIT_TIMEOUT;
#endif

    /* Receive data */
    buf = (uint8_t *)rxBuff;
    while (rxSize--)
    {
        /* Read LPI2C receive fifo register. The register includes a flag to indicate whether */
        /* the FIFO is empty, so we can both get the data and check if we need to keep reading */
        /* using a single register read. */
        uint32_t value;
        do
        {
            /* Check for errors. */
            result = LPI2C_MasterCheckAndClearError(base, LPI2C_MasterGetStatusFlags(base));
            if (result)
            {
                return result;
            }

            value = base->MRDR;
#if LPI2C_WAIT_TIMEOUT
        } while ((value & LPI2C_MRDR_RXEMPTY_MASK) && (--waitTimes));
        if (waitTimes == 0)
        {
            return kStatus_LPI2C_Timeout;
        }
#else
        } while (value & LPI2C_MRDR_RXEMPTY_MASK);
#endif

        *buf++ = value & LPI2C_MRDR_DATA_MASK;
    }

    return kStatus_Success;
}

status_t LPI2C_MasterSend(LPI2C_Type *base, const void *txBuff, size_t txSize)
{
    const uint8_t *buf = (const uint8_t *)((const void *)txBuff);

    assert(txBuff);

    /* Send data buffer */
    while (txSize--)
    {
        /* Wait until there is room in the fifo. This also checks for errors. */
        status_t result = LPI2C_MasterWaitForTxReady(base);
        if (result)
        {
            return result;
        }

        /* Write byte into LPI2C master data register. */
        base->MTDR = *buf++;
    }

    return kStatus_Success;
}

status_t LPI2C_MasterTransferBlocking(LPI2C_Type *base, lpi2c_master_transfer_t *transfer)
{
    status_t result = kStatus_Success;
    uint16_t commandBuffer[7];
    uint32_t cmdCount = 0;

    assert(transfer);
    assert(transfer->subaddressSize <= sizeof(transfer->subaddress));

    /* Return an error if the bus is already in use not by us. */
    result = LPI2C_CheckForBusyBus(base);
    if (result)
    {
        return result;
    }

    /* Clear all flags. */
    LPI2C_MasterClearStatusFlags(base, kMasterClearFlags);

    /* Turn off auto-stop option. */
    base->MCFGR1 &= ~LPI2C_MCFGR1_AUTOSTOP_MASK;

    lpi2c_direction_t direction = transfer->subaddressSize ? kLPI2C_Write : transfer->direction;
    if (!(transfer->flags & kLPI2C_TransferNoStartFlag))
    {
        commandBuffer[cmdCount++] =
            (uint16_t)kStartCmd | (uint16_t)((uint16_t)((uint16_t)transfer->slaveAddress << 1U) | (uint16_t)direction);
    }

    /* Subaddress, MSB first. */
    if (transfer->subaddressSize)
    {
        uint32_t subaddressRemaining = transfer->subaddressSize;
        while (subaddressRemaining--)
        {
            uint8_t subaddressByte = (transfer->subaddress >> (8 * subaddressRemaining)) & 0xff;
            commandBuffer[cmdCount++] = subaddressByte;
        }
    }

    /* Reads need special handling. */
    if ((transfer->dataSize) && (transfer->direction == kLPI2C_Read))
    {
        /* Need to send repeated start if switching directions to read. */
        if (direction == kLPI2C_Write)
        {
            commandBuffer[cmdCount++] =
                (uint16_t)kStartCmd |
                (uint16_t)((uint16_t)((uint16_t)transfer->slaveAddress << 1U) | (uint16_t)kLPI2C_Read);
        }
    }

    /* Send command buffer */
    uint32_t index = 0;
    while (cmdCount--)
    {
        /* Wait until there is room in the fifo. This also checks for errors. */
        result = LPI2C_MasterWaitForTxReady(base);
        if (result)
        {
            return result;
        }

        /* Write byte into LPI2C master data register. */
        base->MTDR = commandBuffer[index];
        index++;
    }

    /* Transmit data. */
    if ((transfer->direction == kLPI2C_Write) && (transfer->dataSize > 0))
    {
        /* Send Data. */
        result = LPI2C_MasterSend(base, transfer->data, transfer->dataSize);
    }

    /* Receive Data. */
    if ((transfer->direction == kLPI2C_Read) && (transfer->dataSize > 0))
    {
        result = LPI2C_MasterReceive(base, transfer->data, transfer->dataSize);
    }

    if (result)
    {
        return result;
    }

    if ((transfer->flags & kLPI2C_TransferNoStopFlag) == 0)
    {
        result = LPI2C_MasterStop(base);
    }

    return result;
}

void LPI2C_MasterTransferCreateHandle(LPI2C_Type *base,
                                      lpi2c_master_handle_t *handle,
                                      lpi2c_master_transfer_callback_t callback,
                                      void *userData)
{
    uint32_t instance;

    assert(handle);

    /* Clear out the handle. */
    memset(handle, 0, sizeof(*handle));

    /* Look up instance number */
    instance = LPI2C_GetInstance(base);

    /* Save base and instance. */
    handle->completionCallback = callback;
    handle->userData = userData;

    /* Save this handle for IRQ use. */
    s_lpi2cMasterHandle[instance] = handle;

    /* Set irq handler. */
    s_lpi2cMasterIsr = LPI2C_MasterTransferHandleIRQ;

    /* Clear internal IRQ enables and enable NVIC IRQ. */
    LPI2C_MasterDisableInterrupts(base, kMasterIrqFlags);

    /* Enable NVIC IRQ, this only enables the IRQ directly connected to the NVIC.
     In some cases the LPI2C IRQ is configured through INTMUX, user needs to enable
     INTMUX IRQ in application code. */
    EnableIRQ(kLpi2cIrqs[instance]);
}

/*!
 * @brief Execute states until FIFOs are exhausted.
 * @param handle Master nonblocking driver handle.
 * @param[out] isDone Set to true if the transfer has completed.
 * @retval #kStatus_Success
 * @retval #kStatus_LPI2C_PinLowTimeout
 * @retval #kStatus_LPI2C_ArbitrationLost
 * @retval #kStatus_LPI2C_Nak
 * @retval #kStatus_LPI2C_FifoError
 */
static status_t LPI2C_RunTransferStateMachine(LPI2C_Type *base, lpi2c_master_handle_t *handle, bool *isDone)
{
    uint32_t status;
    status_t result = kStatus_Success;
    lpi2c_master_transfer_t *xfer;
    size_t txCount;
    size_t rxCount;
    size_t txFifoSize = FSL_FEATURE_LPI2C_FIFO_SIZEn(base);
    bool state_complete = false;

    /* Set default isDone return value. */
    *isDone = false;

    /* Check for errors. */
    status = LPI2C_MasterGetStatusFlags(base);
    result = LPI2C_MasterCheckAndClearError(base, status);
    if (result)
    {
        return result;
    }

    /* Get pointer to private data. */
    xfer = &handle->transfer;

    /* Get fifo counts and compute room in tx fifo. */
    LPI2C_MasterGetFifoCounts(base, &rxCount, &txCount);
    txCount = txFifoSize - txCount;

    while (!state_complete)
    {
        /* Execute the state. */
        switch (handle->state)
        {
            case kSendCommandState:
            {
                /* Make sure there is room in the tx fifo for the next command. */
                if (!txCount--)
                {
                    state_complete = true;
                    break;
                }

                /* Issue command. buf is a uint8_t* pointing at the uint16 command array. */
                base->MTDR = *(uint16_t *)handle->buf;
                handle->buf += sizeof(uint16_t);

                /* Count down until all commands are sent. */
                if (--handle->remainingBytes == 0)
                {
                    /* Choose next state and set up buffer pointer and count. */
                    if (xfer->dataSize)
                    {
                        /* Either a send or receive transfer is next. */
                        handle->state = kTransferDataState;
                        handle->buf = (uint8_t *)xfer->data;
                        handle->remainingBytes = xfer->dataSize;
                        if (xfer->direction == kLPI2C_Read)
                        {
                            /* Disable TX interrupt */
                            LPI2C_MasterDisableInterrupts(base, kLPI2C_MasterTxReadyFlag);
                        }
                    }
                    else
                    {
                        /* No transfer, so move to stop state. */
                        handle->state = kStopState;
                    }
                }
                break;
            }

            case kIssueReadCommandState:
                /* Make sure there is room in the tx fifo for the read command. */
                if (!txCount--)
                {
                    state_complete = true;
                    break;
                }

                base->MTDR = kRxDataCmd | LPI2C_MTDR_DATA(xfer->dataSize - 1);

                /* Move to transfer state. */
                handle->state = kTransferDataState;
                if (xfer->direction == kLPI2C_Read)
                {
                    /* Disable TX interrupt */
                    LPI2C_MasterDisableInterrupts(base, kLPI2C_MasterTxReadyFlag);
                }
                break;

            case kTransferDataState:
                if (xfer->direction == kLPI2C_Write)
                {
                    /* Make sure there is room in the tx fifo. */
                    if (!txCount--)
                    {
                        state_complete = true;
                        break;
                    }

                    /* Put byte to send in fifo. */
                    base->MTDR = *(handle->buf)++;
                }
                else
                {
                    /* XXX handle receive sizes > 256, use kIssueReadCommandState */
                    /* Make sure there is data in the rx fifo. */
                    if (!rxCount--)
                    {
                        state_complete = true;
                        break;
                    }

                    /* Read byte from fifo. */
                    *(handle->buf)++ = base->MRDR & LPI2C_MRDR_DATA_MASK;
                }

                /* Move to stop when the transfer is done. */
                if (--handle->remainingBytes == 0)
                {
                    handle->state = kStopState;
                }
                break;

            case kStopState:
                /* Only issue a stop transition if the caller requested it. */
                if ((xfer->flags & kLPI2C_TransferNoStopFlag) == 0)
                {
                    /* Make sure there is room in the tx fifo for the stop command. */
                    if (!txCount--)
                    {
                        state_complete = true;
                        break;
                    }

                    base->MTDR = kStopCmd;
                }
                else
                {
                    /* Caller doesn't want to send a stop, so we're done now. */
                    *isDone = true;
                    state_complete = true;
                    break;
                }
                handle->state = kWaitForCompletionState;
                break;

            case kWaitForCompletionState:
                /* We stay in this state until the stop state is detected. */
                if (status & kLPI2C_MasterStopDetectFlag)
                {
                    *isDone = true;
                }
                state_complete = true;
                break;
            default:
                assert(false);
                break;
        }
    }
    return result;
}

/*!
 * @brief Prepares the transfer state machine and fills in the command buffer.
 * @param handle Master nonblocking driver handle.
 */
static void LPI2C_InitTransferStateMachine(lpi2c_master_handle_t *handle)
{
    lpi2c_master_transfer_t *xfer = &handle->transfer;

    /* Handle no start option. */
    if (xfer->flags & kLPI2C_TransferNoStartFlag)
    {
        if (xfer->direction == kLPI2C_Read)
        {
            /* Need to issue read command first. */
            handle->state = kIssueReadCommandState;
        }
        else
        {
            /* Start immediately in the data transfer state. */
            handle->state = kTransferDataState;
        }

        handle->buf = (uint8_t *)xfer->data;
        handle->remainingBytes = xfer->dataSize;
    }
    else
    {
        uint16_t *cmd = (uint16_t *)&handle->commandBuffer;
        uint32_t cmdCount = 0;

        /* Initial direction depends on whether a subaddress was provided, and of course the actual */
        /* data transfer direction. */
        lpi2c_direction_t direction = xfer->subaddressSize ? kLPI2C_Write : xfer->direction;

        /* Start command. */
        cmd[cmdCount++] =
            (uint16_t)kStartCmd | (uint16_t)((uint16_t)((uint16_t)xfer->slaveAddress << 1U) | (uint16_t)direction);

        /* Subaddress, MSB first. */
        if (xfer->subaddressSize)
        {
            uint32_t subaddressRemaining = xfer->subaddressSize;
            while (subaddressRemaining--)
            {
                uint8_t subaddressByte = (xfer->subaddress >> (8 * subaddressRemaining)) & 0xff;
                cmd[cmdCount++] = subaddressByte;
            }
        }

        /* Reads need special handling. */
        if ((xfer->dataSize) && (xfer->direction == kLPI2C_Read))
        {
            /* Need to send repeated start if switching directions to read. */
            if (direction == kLPI2C_Write)
            {
                cmd[cmdCount++] = (uint16_t)kStartCmd |
                                  (uint16_t)((uint16_t)((uint16_t)xfer->slaveAddress << 1U) | (uint16_t)kLPI2C_Read);
            }

            /* Read command. */
            cmd[cmdCount++] = kRxDataCmd | LPI2C_MTDR_DATA(xfer->dataSize - 1);
        }

        /* Set up state machine for transferring the commands. */
        handle->state = kSendCommandState;
        handle->remainingBytes = cmdCount;
        handle->buf = (uint8_t *)&handle->commandBuffer;
    }
}

status_t LPI2C_MasterTransferNonBlocking(LPI2C_Type *base,
                                         lpi2c_master_handle_t *handle,
                                         lpi2c_master_transfer_t *transfer)
{
    status_t result;

    assert(handle);
    assert(transfer);
    assert(transfer->subaddressSize <= sizeof(transfer->subaddress));

    /* Return busy if another transaction is in progress. */
    if (handle->state != kIdleState)
    {
        return kStatus_LPI2C_Busy;
    }

    /* Return an error if the bus is already in use not by us. */
    result = LPI2C_CheckForBusyBus(base);
    if (result)
    {
        return result;
    }

    /* Disable LPI2C IRQ sources while we configure stuff. */
    LPI2C_MasterDisableInterrupts(base, kMasterIrqFlags);

    /* Save transfer into handle. */
    handle->transfer = *transfer;

    /* Generate commands to send. */
    LPI2C_InitTransferStateMachine(handle);

    /* Clear all flags. */
    LPI2C_MasterClearStatusFlags(base, kMasterClearFlags);

    /* Turn off auto-stop option. */
    base->MCFGR1 &= ~LPI2C_MCFGR1_AUTOSTOP_MASK;

    /* Enable LPI2C internal IRQ sources. NVIC IRQ was enabled in CreateHandle() */
    LPI2C_MasterEnableInterrupts(base, kMasterIrqFlags);

    return result;
}

status_t LPI2C_MasterTransferGetCount(LPI2C_Type *base, lpi2c_master_handle_t *handle, size_t *count)
{
    assert(handle);

    if (!count)
    {
        return kStatus_InvalidArgument;
    }

    /* Catch when there is not an active transfer. */
    if (handle->state == kIdleState)
    {
        *count = 0;
        return kStatus_NoTransferInProgress;
    }

    uint8_t state;
    uint16_t remainingBytes;
    uint32_t dataSize;

    /* Cache some fields with IRQs disabled. This ensures all field values */
    /* are synchronized with each other during an ongoing transfer. */
    uint32_t irqs = LPI2C_MasterGetEnabledInterrupts(base);
    LPI2C_MasterDisableInterrupts(base, irqs);
    state = handle->state;
    remainingBytes = handle->remainingBytes;
    dataSize = handle->transfer.dataSize;
    LPI2C_MasterEnableInterrupts(base, irqs);

    /* Get transfer count based on current transfer state. */
    switch (state)
    {
        case kIdleState:
        case kSendCommandState:
        case kIssueReadCommandState: /* XXX return correct value for this state when >256 reads are supported */
            *count = 0;
            break;

        case kTransferDataState:
            *count = dataSize - remainingBytes;
            break;

        case kStopState:
        case kWaitForCompletionState:
        default:
            *count = dataSize;
            break;
    }

    return kStatus_Success;
}

void LPI2C_MasterTransferAbort(LPI2C_Type *base, lpi2c_master_handle_t *handle)
{
    if (handle->state != kIdleState)
    {
        /* Disable internal IRQ enables. */
        LPI2C_MasterDisableInterrupts(base, kMasterIrqFlags);

        /* Reset fifos. */
        base->MCR |= LPI2C_MCR_RRF_MASK | LPI2C_MCR_RTF_MASK;

        /* Send a stop command to finalize the transfer. */
        base->MTDR = kStopCmd;

        /* Reset handle. */
        handle->state = kIdleState;
    }
}

void LPI2C_MasterTransferHandleIRQ(LPI2C_Type *base, lpi2c_master_handle_t *handle)
{
    bool isDone;
    status_t result;

    /* Don't do anything if we don't have a valid handle. */
    if (!handle)
    {
        return;
    }

    if (handle->state == kIdleState)
    {
        return;
    }

    result = LPI2C_RunTransferStateMachine(base, handle, &isDone);

    if (isDone || (result != kStatus_Success))
    {
        /* XXX need to handle data that may be in rx fifo below watermark level? */

        /* XXX handle error, terminate xfer */

        /* Disable internal IRQ enables. */
        LPI2C_MasterDisableInterrupts(base, kMasterIrqFlags);

        /* Set handle to idle state. */
        handle->state = kIdleState;

        /* Invoke callback. */
        if (handle->completionCallback)
        {
            handle->completionCallback(base, handle, result, handle->userData);
        }
    }
}

void LPI2C_SlaveGetDefaultConfig(lpi2c_slave_config_t *slaveConfig)
{
    slaveConfig->enableSlave = true;
    slaveConfig->address0 = 0U;
    slaveConfig->address1 = 0U;
    slaveConfig->addressMatchMode = kLPI2C_MatchAddress0;
    slaveConfig->filterDozeEnable = true;
    slaveConfig->filterEnable = true;
    slaveConfig->enableGeneralCall = false;
    slaveConfig->sclStall.enableAck = false;
    slaveConfig->sclStall.enableTx = true;
    slaveConfig->sclStall.enableRx = true;
    slaveConfig->sclStall.enableAddress = false;
    slaveConfig->ignoreAck = false;
    slaveConfig->enableReceivedAddressRead = false;
    slaveConfig->sdaGlitchFilterWidth_ns = 0; /* TODO determine default width values */
    slaveConfig->sclGlitchFilterWidth_ns = 0;
    slaveConfig->dataValidDelay_ns = 0;
    slaveConfig->clockHoldTime_ns = 0;
}

void LPI2C_SlaveInit(LPI2C_Type *base, const lpi2c_slave_config_t *slaveConfig, uint32_t sourceClock_Hz)
{
#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)

    uint32_t instance = LPI2C_GetInstance(base);

    /* Ungate the clock. */
    CLOCK_EnableClock(kLpi2cClocks[instance]);
#if defined(LPI2C_PERIPH_CLOCKS)
    /* Ungate the functional clock in initialize function. */
    CLOCK_EnableClock(kLpi2cPeriphClocks[instance]);
#endif

#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */

    /* Restore to reset conditions. */
    LPI2C_SlaveReset(base);

    /* Configure peripheral. */
    base->SAMR = LPI2C_SAMR_ADDR0(slaveConfig->address0) | LPI2C_SAMR_ADDR1(slaveConfig->address1);

    base->SCFGR1 =
        LPI2C_SCFGR1_ADDRCFG(slaveConfig->addressMatchMode) | LPI2C_SCFGR1_IGNACK(slaveConfig->ignoreAck) |
        LPI2C_SCFGR1_RXCFG(slaveConfig->enableReceivedAddressRead) | LPI2C_SCFGR1_GCEN(slaveConfig->enableGeneralCall) |
        LPI2C_SCFGR1_ACKSTALL(slaveConfig->sclStall.enableAck) | LPI2C_SCFGR1_TXDSTALL(slaveConfig->sclStall.enableTx) |
        LPI2C_SCFGR1_RXSTALL(slaveConfig->sclStall.enableRx) |
        LPI2C_SCFGR1_ADRSTALL(slaveConfig->sclStall.enableAddress);

    base->SCFGR2 =
        LPI2C_SCFGR2_FILTSDA(LPI2C_GetCyclesForWidth(sourceClock_Hz, slaveConfig->sdaGlitchFilterWidth_ns,
                                                     (LPI2C_SCFGR2_FILTSDA_MASK >> LPI2C_SCFGR2_FILTSDA_SHIFT), 1)) |
        LPI2C_SCFGR2_FILTSCL(LPI2C_GetCyclesForWidth(sourceClock_Hz, slaveConfig->sclGlitchFilterWidth_ns,
                                                     (LPI2C_SCFGR2_FILTSCL_MASK >> LPI2C_SCFGR2_FILTSCL_SHIFT), 1)) |
        LPI2C_SCFGR2_DATAVD(LPI2C_GetCyclesForWidth(sourceClock_Hz, slaveConfig->dataValidDelay_ns,
                                                    (LPI2C_SCFGR2_DATAVD_MASK >> LPI2C_SCFGR2_DATAVD_SHIFT), 1)) |
        LPI2C_SCFGR2_CLKHOLD(LPI2C_GetCyclesForWidth(sourceClock_Hz, slaveConfig->clockHoldTime_ns,
                                                     (LPI2C_SCFGR2_CLKHOLD_MASK >> LPI2C_SCFGR2_CLKHOLD_SHIFT), 1));

    /* Save SCR to last so we don't enable slave until it is configured */
    base->SCR = LPI2C_SCR_FILTDZ(slaveConfig->filterDozeEnable) | LPI2C_SCR_FILTEN(slaveConfig->filterEnable) |
                LPI2C_SCR_SEN(slaveConfig->enableSlave);
}

void LPI2C_SlaveDeinit(LPI2C_Type *base)
{
    LPI2C_SlaveReset(base);

#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)

    uint32_t instance = LPI2C_GetInstance(base);

    /* Gate the clock. */
    CLOCK_DisableClock(kLpi2cClocks[instance]);

#if defined(LPI2C_PERIPH_CLOCKS)
    /* Gate the functional clock. */
    CLOCK_DisableClock(kLpi2cPeriphClocks[instance]);
#endif

#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */
}

/*!
 * @brief Convert provided flags to status code, and clear any errors if present.
 * @param base The LPI2C peripheral base address.
 * @param status Current status flags value that will be checked.
 * @retval #kStatus_Success
 * @retval #kStatus_LPI2C_BitError
 * @retval #kStatus_LPI2C_FifoError
 */
static status_t LPI2C_SlaveCheckAndClearError(LPI2C_Type *base, uint32_t flags)
{
    status_t result = kStatus_Success;

    flags &= kSlaveErrorFlags;
    if (flags)
    {
        if (flags & kLPI2C_SlaveBitErrFlag)
        {
            result = kStatus_LPI2C_BitError;
        }
        else if (flags & kLPI2C_SlaveFifoErrFlag)
        {
            result = kStatus_LPI2C_FifoError;
        }
        else
        {
            assert(false);
        }

        /* Clear the errors. */
        LPI2C_SlaveClearStatusFlags(base, flags);
    }

    return result;
}

status_t LPI2C_SlaveSend(LPI2C_Type *base, const void *txBuff, size_t txSize, size_t *actualTxSize)
{
    const uint8_t *buf = (const uint8_t *)((const void *)txBuff);
    size_t remaining = txSize;

    assert(txBuff);

#if LPI2C_WAIT_TIMEOUT
    uint32_t waitTimes = LPI2C_WAIT_TIMEOUT;
#endif

    while (remaining)
    {
        uint32_t flags;
        status_t result;

        /* Wait until we can transmit. */
        do
        {
            /* Check for errors */
            flags = LPI2C_SlaveGetStatusFlags(base);
            result = LPI2C_SlaveCheckAndClearError(base, flags);
            if (result)
            {
                if (actualTxSize)
                {
                    *actualTxSize = txSize - remaining;
                }
                return result;
            }
#if LPI2C_WAIT_TIMEOUT
        } while (
            (!(flags & (kLPI2C_SlaveTxReadyFlag | kLPI2C_SlaveStopDetectFlag | kLPI2C_SlaveRepeatedStartDetectFlag))) &&
            (--waitTimes));
        if (waitTimes == 0)
        {
            return kStatus_LPI2C_Timeout;
        }
#else
        } while (
            !(flags & (kLPI2C_SlaveTxReadyFlag | kLPI2C_SlaveStopDetectFlag | kLPI2C_SlaveRepeatedStartDetectFlag)));
#endif

        /* Send a byte. */
        if (flags & kLPI2C_SlaveTxReadyFlag)
        {
            base->STDR = *buf++;
            --remaining;
        }

        /* Exit loop if we see a stop or restart */
        if (flags & (kLPI2C_SlaveStopDetectFlag | kLPI2C_SlaveRepeatedStartDetectFlag))
        {
            LPI2C_SlaveClearStatusFlags(base, kLPI2C_SlaveStopDetectFlag | kLPI2C_SlaveRepeatedStartDetectFlag);
            break;
        }
    }

    if (actualTxSize)
    {
        *actualTxSize = txSize - remaining;
    }

    return kStatus_Success;
}

status_t LPI2C_SlaveReceive(LPI2C_Type *base, void *rxBuff, size_t rxSize, size_t *actualRxSize)
{
    uint8_t *buf = (uint8_t *)rxBuff;
    size_t remaining = rxSize;

    assert(rxBuff);

#if LPI2C_WAIT_TIMEOUT
    uint32_t waitTimes = LPI2C_WAIT_TIMEOUT;
#endif

    while (remaining)
    {
        uint32_t flags;
        status_t result;

        /* Wait until we can receive. */
        do
        {
            /* Check for errors */
            flags = LPI2C_SlaveGetStatusFlags(base);
            result = LPI2C_SlaveCheckAndClearError(base, flags);
            if (result)
            {
                if (actualRxSize)
                {
                    *actualRxSize = rxSize - remaining;
                }
                return result;
            }
#if LPI2C_WAIT_TIMEOUT
        } while (
            (!(flags & (kLPI2C_SlaveRxReadyFlag | kLPI2C_SlaveStopDetectFlag | kLPI2C_SlaveRepeatedStartDetectFlag))) &&
            (--waitTimes));
        if (waitTimes == 0)
        {
            return kStatus_LPI2C_Timeout;
        }
#else
        } while (
            !(flags & (kLPI2C_SlaveRxReadyFlag | kLPI2C_SlaveStopDetectFlag | kLPI2C_SlaveRepeatedStartDetectFlag)));
#endif

        /* Receive a byte. */
        if (flags & kLPI2C_SlaveRxReadyFlag)
        {
            *buf++ = base->SRDR & LPI2C_SRDR_DATA_MASK;
            --remaining;
        }

        /* Exit loop if we see a stop or restart */
        if (flags & (kLPI2C_SlaveStopDetectFlag | kLPI2C_SlaveRepeatedStartDetectFlag))
        {
            LPI2C_SlaveClearStatusFlags(base, kLPI2C_SlaveStopDetectFlag | kLPI2C_SlaveRepeatedStartDetectFlag);
            break;
        }
    }

    if (actualRxSize)
    {
        *actualRxSize = rxSize - remaining;
    }

    return kStatus_Success;
}

void LPI2C_SlaveTransferCreateHandle(LPI2C_Type *base,
                                     lpi2c_slave_handle_t *handle,
                                     lpi2c_slave_transfer_callback_t callback,
                                     void *userData)
{
    uint32_t instance;

    assert(handle);

    /* Clear out the handle. */
    memset(handle, 0, sizeof(*handle));

    /* Look up instance number */
    instance = LPI2C_GetInstance(base);

    /* Save base and instance. */
    handle->callback = callback;
    handle->userData = userData;

    /* Save this handle for IRQ use. */
    s_lpi2cSlaveHandle[instance] = handle;

    /* Set irq handler. */
    s_lpi2cSlaveIsr = LPI2C_SlaveTransferHandleIRQ;

    /* Clear internal IRQ enables and enable NVIC IRQ. */
    LPI2C_SlaveDisableInterrupts(base, kSlaveIrqFlags);
    EnableIRQ(kLpi2cIrqs[instance]);

    /* Nack by default. */
    base->STAR = LPI2C_STAR_TXNACK_MASK;
}

status_t LPI2C_SlaveTransferNonBlocking(LPI2C_Type *base, lpi2c_slave_handle_t *handle, uint32_t eventMask)
{
    uint32_t status;

    assert(handle);

    /* Return busy if another transaction is in progress. */
    if (handle->isBusy)
    {
        return kStatus_LPI2C_Busy;
    }

    /* Return an error if the bus is already in use not by us. */
    status = LPI2C_SlaveGetStatusFlags(base);
    if ((status & kLPI2C_SlaveBusBusyFlag) && (!(status & kLPI2C_SlaveBusyFlag)))
    {
        return kStatus_LPI2C_Busy;
    }

    /* Disable LPI2C IRQ sources while we configure stuff. */
    LPI2C_SlaveDisableInterrupts(base, kSlaveIrqFlags);

    /* Clear transfer in handle. */
    memset(&handle->transfer, 0, sizeof(handle->transfer));

    /* Record that we're busy. */
    handle->isBusy = true;

    /* Set up event mask. tx and rx are always enabled. */
    handle->eventMask = eventMask | kLPI2C_SlaveTransmitEvent | kLPI2C_SlaveReceiveEvent;

    /* Ack by default. */
    base->STAR = 0;

    /* Clear all flags. */
    LPI2C_SlaveClearStatusFlags(base, kSlaveClearFlags);

    /* Enable LPI2C internal IRQ sources. NVIC IRQ was enabled in CreateHandle() */
    LPI2C_SlaveEnableInterrupts(base, kSlaveIrqFlags);

    return kStatus_Success;
}

status_t LPI2C_SlaveTransferGetCount(LPI2C_Type *base, lpi2c_slave_handle_t *handle, size_t *count)
{
    assert(handle);

    if (!count)
    {
        return kStatus_InvalidArgument;
    }

    /* Catch when there is not an active transfer. */
    if (!handle->isBusy)
    {
        *count = 0;
        return kStatus_NoTransferInProgress;
    }

    /* For an active transfer, just return the count from the handle. */
    *count = handle->transferredCount;

    return kStatus_Success;
}

void LPI2C_SlaveTransferAbort(LPI2C_Type *base, lpi2c_slave_handle_t *handle)
{
    assert(handle);

    /* Return idle if no transaction is in progress. */
    if (handle->isBusy)
    {
        /* Disable LPI2C IRQ sources. */
        LPI2C_SlaveDisableInterrupts(base, kSlaveIrqFlags);

        /* Nack by default. */
        base->STAR = LPI2C_STAR_TXNACK_MASK;

        /* Reset transfer info. */
        memset(&handle->transfer, 0, sizeof(handle->transfer));

        /* We're no longer busy. */
        handle->isBusy = false;
    }
}

void LPI2C_SlaveTransferHandleIRQ(LPI2C_Type *base, lpi2c_slave_handle_t *handle)
{
    uint32_t flags;
    lpi2c_slave_transfer_t *xfer;

    /* Check for a valid handle in case of a spurious interrupt. */
    if (!handle)
    {
        return;
    }

    xfer = &handle->transfer;

    /* Get status flags. */
    flags = LPI2C_SlaveGetStatusFlags(base);

    if (flags & (kLPI2C_SlaveBitErrFlag | kLPI2C_SlaveFifoErrFlag))
    {
        xfer->event = kLPI2C_SlaveCompletionEvent;
        xfer->completionStatus = LPI2C_SlaveCheckAndClearError(base, flags);

        if ((handle->eventMask & kLPI2C_SlaveCompletionEvent) && (handle->callback))
        {
            handle->callback(base, xfer, handle->userData);
        }
        return;
    }
    if (flags & (kLPI2C_SlaveRepeatedStartDetectFlag | kLPI2C_SlaveStopDetectFlag))
    {
        xfer->event = (flags & kLPI2C_SlaveRepeatedStartDetectFlag) ? kLPI2C_SlaveRepeatedStartEvent :
                                                                      kLPI2C_SlaveCompletionEvent;
        xfer->receivedAddress = 0;
        xfer->completionStatus = kStatus_Success;
        xfer->transferredCount = handle->transferredCount;

        if (xfer->event == kLPI2C_SlaveCompletionEvent)
        {
            handle->isBusy = false;
        }

        if (handle->wasTransmit)
        {
            /* Subtract one from the transmit count to offset the fact that LPI2C asserts the */
            /* tx flag before it sees the nack from the master-receiver, thus causing one more */
            /* count that the master actually receives. */
            --xfer->transferredCount;
            handle->wasTransmit = false;
        }

        /* Clear the flag. */
        LPI2C_SlaveClearStatusFlags(base, flags & (kLPI2C_SlaveRepeatedStartDetectFlag | kLPI2C_SlaveStopDetectFlag));

        /* Revert to sending an Ack by default, in case we sent a Nack for receive. */
        base->STAR = 0;

        if ((handle->eventMask & xfer->event) && (handle->callback))
        {
            handle->callback(base, xfer, handle->userData);
        }

        /* Clean up transfer info on completion, after the callback has been invoked. */
        memset(&handle->transfer, 0, sizeof(handle->transfer));
    }
    if (flags & kLPI2C_SlaveAddressValidFlag)
    {
        xfer->event = kLPI2C_SlaveAddressMatchEvent;
        xfer->receivedAddress = base->SASR & LPI2C_SASR_RADDR_MASK;

        if ((handle->eventMask & kLPI2C_SlaveAddressMatchEvent) && (handle->callback))
        {
            handle->callback(base, xfer, handle->userData);
        }
    }
    if (flags & kLPI2C_SlaveTransmitAckFlag)
    {
        xfer->event = kLPI2C_SlaveTransmitAckEvent;

        if ((handle->eventMask & kLPI2C_SlaveTransmitAckEvent) && (handle->callback))
        {
            handle->callback(base, xfer, handle->userData);
        }
    }

    /* Handle transmit and receive. */
    if (flags & kLPI2C_SlaveTxReadyFlag)
    {
        handle->wasTransmit = true;

        /* If we're out of data, invoke callback to get more. */
        if ((!xfer->data) || (!xfer->dataSize))
        {
            xfer->event = kLPI2C_SlaveTransmitEvent;
            if (handle->callback)
            {
                handle->callback(base, xfer, handle->userData);
            }

            /* Clear the transferred count now that we have a new buffer. */
            handle->transferredCount = 0;
        }

        /* Transmit a byte. */
        if ((xfer->data) && (xfer->dataSize))
        {
            base->STDR = *xfer->data++;
            --xfer->dataSize;
            ++handle->transferredCount;
        }
    }
    if (flags & kLPI2C_SlaveRxReadyFlag)
    {
        /* If we're out of room in the buffer, invoke callback to get another. */
        if ((!xfer->data) || (!xfer->dataSize))
        {
            xfer->event = kLPI2C_SlaveReceiveEvent;
            if (handle->callback)
            {
                handle->callback(base, xfer, handle->userData);
            }

            /* Clear the transferred count now that we have a new buffer. */
            handle->transferredCount = 0;
        }

        /* Receive a byte. */
        if ((xfer->data) && (xfer->dataSize))
        {
            *xfer->data++ = base->SRDR;
            --xfer->dataSize;
            ++handle->transferredCount;
        }
        else
        {
            /* We don't have any room to receive more data, so send a nack. */
            base->STAR = LPI2C_STAR_TXNACK_MASK;
        }
    }
}

/*!
 * @brief Shared IRQ handler that can call both master and slave ISRs.
 *
 * The master and slave ISRs are called through function pointers in order to decouple
 * this code from the ISR functions. Without this, the linker would always pull in both
 * ISRs and every function they call, even if only the functional API was used.
 *
 * @param base The LPI2C peripheral base address.
 * @param instance The LPI2C peripheral instance number.
 */
static void LPI2C_CommonIRQHandler(LPI2C_Type *base, uint32_t instance)
{
    /* Check for master IRQ. */
    if ((base->MCR & LPI2C_MCR_MEN_MASK) && s_lpi2cMasterIsr)
    {
        /* Master mode. */
        s_lpi2cMasterIsr(base, s_lpi2cMasterHandle[instance]);
    }

    /* Check for slave IRQ. */
    if ((base->SCR & LPI2C_SCR_SEN_MASK) && s_lpi2cSlaveIsr)
    {
        /* Slave mode. */
        s_lpi2cSlaveIsr(base, s_lpi2cSlaveHandle[instance]);
    }
/* Add for ARM errata 838869, affects Cortex-M4, Cortex-M4F Store immediate overlapping
  exception return operation might vector to incorrect interrupt */
#if defined __CORTEX_M && (__CORTEX_M == 4U)
    __DSB();
#endif
}

#if defined(LPI2C0)
/* Implementation of LPI2C0 handler named in startup code. */
void LPI2C0_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(LPI2C0, 0);
}
#endif

#if defined(LPI2C1)
/* Implementation of LPI2C1 handler named in startup code. */
void LPI2C1_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(LPI2C1, 1);
}
#endif

#if defined(LPI2C2)
/* Implementation of LPI2C2 handler named in startup code. */
void LPI2C2_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(LPI2C2, 2);
}
#endif

#if defined(LPI2C3)
/* Implementation of LPI2C3 handler named in startup code. */
void LPI2C3_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(LPI2C3, 3);
}
#endif

#if defined(LPI2C4)
/* Implementation of LPI2C4 handler named in startup code. */
void LPI2C4_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(LPI2C4, 4);
}
#endif

#if defined(CM4_0__LPI2C)
/* Implementation of CM4_0__LPI2C handler named in startup code. */
void M4_0_LPI2C_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(CM4_0__LPI2C, LPI2C_GetInstance(CM4_0__LPI2C));
}
#endif

#if defined(CM4__LPI2C)
/* Implementation of CM4__LPI2C handler named in startup code. */
void M4_LPI2C_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(CM4__LPI2C, LPI2C_GetInstance(CM4__LPI2C));
}
#endif

#if defined(CM4_1__LPI2C)
/* Implementation of CM4_1__LPI2C handler named in startup code. */
void M4_1_LPI2C_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(CM4_1__LPI2C, LPI2C_GetInstance(CM4_1__LPI2C));
}
#endif

#if defined(DMA__LPI2C0)
/* Implementation of DMA__LPI2C0 handler named in startup code. */
void DMA_I2C0_INT_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(DMA__LPI2C0, LPI2C_GetInstance(DMA__LPI2C0));
}
#endif

#if defined(DMA__LPI2C1)
/* Implementation of DMA__LPI2C1 handler named in startup code. */
void DMA_I2C1_INT_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(DMA__LPI2C1, LPI2C_GetInstance(DMA__LPI2C1));
}
#endif

#if defined(DMA__LPI2C2)
/* Implementation of DMA__LPI2C2 handler named in startup code. */
void DMA_I2C2_INT_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(DMA__LPI2C2, LPI2C_GetInstance(DMA__LPI2C2));
}
#endif

#if defined(DMA__LPI2C3)
/* Implementation of DMA__LPI2C3 handler named in startup code. */
void DMA_I2C3_INT_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(DMA__LPI2C3, LPI2C_GetInstance(DMA__LPI2C3));
}
#endif

#if defined(DMA__LPI2C4)
/* Implementation of DMA__LPI2C3 handler named in startup code. */
void DMA_I2C4_INT_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(DMA__LPI2C4, LPI2C_GetInstance(DMA__LPI2C4));
}
#endif

#if defined(ADMA__LPI2C0)
/* Implementation of DMA__LPI2C0 handler named in startup code. */
void ADMA_I2C0_INT_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(ADMA__LPI2C0, LPI2C_GetInstance(ADMA__LPI2C0));
}
#endif

#if defined(ADMA__LPI2C1)
/* Implementation of DMA__LPI2C1 handler named in startup code. */
void ADMA_I2C1_INT_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(ADMA__LPI2C1, LPI2C_GetInstance(ADMA__LPI2C1));
}
#endif

#if defined(ADMA__LPI2C2)
/* Implementation of DMA__LPI2C2 handler named in startup code. */
void ADMA_I2C2_INT_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(ADMA__LPI2C2, LPI2C_GetInstance(ADMA__LPI2C2));
}
#endif

#if defined(ADMA__LPI2C3)
/* Implementation of DMA__LPI2C3 handler named in startup code. */
void ADMA_I2C3_INT_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(ADMA__LPI2C3, LPI2C_GetInstance(ADMA__LPI2C3));
}
#endif

#if defined(ADMA__LPI2C4)
/* Implementation of DMA__LPI2C3 handler named in startup code. */
void ADMA_I2C4_INT_DriverIRQHandler(void)
{
    LPI2C_CommonIRQHandler(ADMA__LPI2C4, LPI2C_GetInstance(ADMA__LPI2C4));
}
#endif