/*
 * Copyright (c) 2016, Freescale Semiconductor, Inc.
 * Copyright 2016-2019 NXP
 * All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include "fsl_i2c_dma.h"
#include "fsl_flexcomm.h"

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

/* Component ID definition, used by tools. */
#ifndef FSL_COMPONENT_ID
#define FSL_COMPONENT_ID "platform.drivers.flexcomm_i2c_dma"
#endif

/*<! @brief Structure definition for i2c_master_dma_handle_t. The structure is private. */
typedef struct _i2c_master_dma_private_handle
{
    I2C_Type *base;
    i2c_master_dma_handle_t *handle;
} i2c_master_dma_private_handle_t;

/*!
 * @brief Used for conversion from `flexcomm_irq_handler_t` to `flexcomm_i2c_dma_master_irq_handler_t`
 */
typedef union i2c_dma_to_flexcomm
{
    flexcomm_i2c_dma_master_irq_handler_t i2c_dma_master_handler;
    flexcomm_irq_handler_t flexcomm_handler;
} i2c_dma_to_flexcomm_t;

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

/*!
 * @brief DMA callback for I2C master DMA driver.
 *
 * @param handle DMA handler for I2C master DMA driver
 * @param userData user param passed to the callback function
 */
static void I2C_MasterTransferCallbackDMA(dma_handle_t *handle, void *userData, bool transferDone, uint32_t intmode);

/*!
 * @brief Set up master transfer, send slave address and sub address(if any), wait until the
 * wait until address sent status return.
 *
 * @param base I2C peripheral base address.
 * @param handle pointer to i2c_master_dma_handle_t structure which stores the transfer state.
 * @param xfer pointer to i2c_master_transfer_t structure.
 */
static status_t I2C_InitTransferStateMachineDMA(I2C_Type *base,
                                                i2c_master_dma_handle_t *handle,
                                                i2c_master_transfer_t *xfer);

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

/*<! Private handle only used for internally. */
static i2c_master_dma_private_handle_t s_dmaPrivateHandle[FSL_FEATURE_SOC_I2C_COUNT];

/*! @brief IRQ name array */
static const IRQn_Type s_i2cIRQ[] = I2C_IRQS;

/*******************************************************************************
 * Codes
 ******************************************************************************/

/*!
 * @brief Prepares the transfer state machine and fills in the command buffer.
 * @param handle Master nonblocking driver handle.
 */
static status_t I2C_InitTransferStateMachineDMA(I2C_Type *base,
                                                i2c_master_dma_handle_t *handle,
                                                i2c_master_transfer_t *xfer)
{
    struct _i2c_master_transfer *transfer;

    handle->transfer = *xfer;
    transfer         = &(handle->transfer);

    handle->transferCount     = 0U;
    handle->remainingBytesDMA = 0U;
    handle->buf               = (uint8_t *)transfer->data;
    handle->remainingSubaddr  = 0U;

    if ((transfer->flags & (uint32_t)kI2C_TransferNoStartFlag) != 0U)
    {
        /* Start condition shall be ommited, switch directly to next phase */
        if (transfer->dataSize == 0U)
        {
            handle->state = (uint8_t)kStopState;
        }
        else if (handle->transfer.direction == kI2C_Write)
        {
            handle->state = (uint8_t)kTransmitDataState;
        }
        else if (handle->transfer.direction == kI2C_Read)
        {
            handle->state = (xfer->dataSize == 1U) ? (uint8_t)kReceiveLastDataState : (uint8_t)kReceiveDataState;
        }
        else
        {
            return kStatus_I2C_InvalidParameter;
        }
    }
    else
    {
        if (transfer->subaddressSize != 0U)
        {
            int i;
            uint32_t subaddress;

            if (transfer->subaddressSize > sizeof(handle->subaddrBuf))
            {
                return kStatus_I2C_InvalidParameter;
            }

            /* Prepare subaddress transmit buffer, most significant byte is stored at the lowest address */
            subaddress = xfer->subaddress;
            for (i = (int)xfer->subaddressSize - 1; i >= 0; i--)
            {
                handle->subaddrBuf[i] = (uint8_t)subaddress & 0xffU;
                subaddress >>= 8;
            }
            handle->remainingSubaddr = transfer->subaddressSize;
        }

        handle->state = (uint8_t)kStartState;
    }

    return kStatus_Success;
}

static void I2C_RunDMATransfer(I2C_Type *base, i2c_master_dma_handle_t *handle)
{
    uint32_t transfer_size;
    dma_transfer_config_t xferConfig;
    uint32_t address;
    address = (uint32_t)&base->MSTDAT;

    /* Update transfer count */
    int32_t count = handle->buf - (uint8_t *)handle->transfer.data;
    assert(count >= 0);
    handle->transferCount = (uint32_t)count;

    /* Check if there is anything to be transferred at all */
    if (handle->remainingBytesDMA == 0U)
    {
        /* No data to be transferrred, disable DMA */
        base->MSTCTL = 0;
        return;
    }

    /* Calculate transfer size */
    transfer_size = handle->remainingBytesDMA;
    if (transfer_size > (uint32_t)I2C_MAX_DMA_TRANSFER_COUNT)
    {
        transfer_size = (uint32_t)I2C_MAX_DMA_TRANSFER_COUNT;
    }

    switch (handle->transfer.direction)
    {
        case kI2C_Write:
            DMA_PrepareTransfer(&xferConfig, handle->buf, (uint32_t *)address, sizeof(uint8_t), transfer_size,
                                kDMA_MemoryToPeripheral, NULL);
            break;

        case kI2C_Read:
            DMA_PrepareTransfer(&xferConfig, (uint32_t *)address, handle->buf, sizeof(uint8_t), transfer_size,
                                kDMA_PeripheralToMemory, NULL);
            break;

        default:
            /* This should never happen */
            assert(0);
            break;
    }

    (void)DMA_SubmitTransfer(handle->dmaHandle, &xferConfig);
    DMA_StartTransfer(handle->dmaHandle);

    handle->remainingBytesDMA -= transfer_size;
    handle->buf += transfer_size;
}

/*!
 * @brief Execute states until the transfer is done.
 * @param handle Master nonblocking driver handle.
 * @param[out] isDone Set to true if the transfer has completed.
 * @retval #kStatus_Success
 * @retval #kStatus_I2C_ArbitrationLost
 * @retval #kStatus_I2C_Nak
 */
static status_t I2C_RunTransferStateMachineDMA(I2C_Type *base, i2c_master_dma_handle_t *handle, bool *isDone)
{
    uint32_t status;
    uint32_t master_state;
    struct _i2c_master_transfer *transfer;
    dma_transfer_config_t xferConfig;
    status_t err;
    uint32_t start_flag = 0U;
    uint32_t address;
    address = (uint32_t)&base->MSTDAT;

    transfer = &(handle->transfer);

    *isDone = false;

    status = I2C_GetStatusFlags(base);

    if ((status & (uint32_t)I2C_STAT_MSTARBLOSS_MASK) != 0U)
    {
        I2C_MasterClearStatusFlags(base, I2C_STAT_MSTARBLOSS_MASK);
        DMA_AbortTransfer(handle->dmaHandle);
        base->MSTCTL = 0;
        return kStatus_I2C_ArbitrationLost;
    }

    if ((status & (uint32_t)I2C_STAT_MSTSTSTPERR_MASK) != 0U)
    {
        I2C_MasterClearStatusFlags(base, I2C_STAT_MSTSTSTPERR_MASK);
        DMA_AbortTransfer(handle->dmaHandle);
        base->MSTCTL = 0;
        return kStatus_I2C_StartStopError;
    }

    if ((status & (uint32_t)I2C_STAT_MSTPENDING_MASK) == 0U)
    {
        return kStatus_I2C_Busy;
    }

    /* Get the state of the I2C module */
    master_state = (status & (uint32_t)I2C_STAT_MSTSTATE_MASK) >> I2C_STAT_MSTSTATE_SHIFT;

    if ((master_state == (uint32_t)I2C_STAT_MSTCODE_NACKADR) || (master_state == (uint32_t)I2C_STAT_MSTCODE_NACKDAT))
    {
        /* Slave NACKed last byte, issue stop and return error */
        DMA_AbortTransfer(handle->dmaHandle);
        base->MSTCTL  = I2C_MSTCTL_MSTSTOP_MASK;
        handle->state = (uint8_t)kWaitForCompletionState;
        return kStatus_I2C_Nak;
    }

    err = kStatus_Success;

    if (handle->state == (uint8_t)kStartState)
    {
        /* set start flag for later use */
        start_flag = I2C_MSTCTL_MSTSTART_MASK;

        if (handle->remainingSubaddr != 0U)
        {
            base->MSTDAT  = (uint32_t)transfer->slaveAddress << 1;
            handle->state = (uint8_t)kTransmitSubaddrState;
        }
        else if (transfer->direction == kI2C_Write)
        {
            base->MSTDAT = (uint32_t)transfer->slaveAddress << 1;
            if (transfer->dataSize == 0U)
            {
                /* No data to be transferred, initiate start and schedule stop */
                base->MSTCTL  = I2C_MSTCTL_MSTSTART_MASK;
                handle->state = (uint8_t)kStopState;
                return err;
            }
            handle->state = (uint8_t)kTransmitDataState;
        }
        else if ((transfer->direction == kI2C_Read) && (transfer->dataSize > 0U))
        {
            base->MSTDAT = ((uint32_t)transfer->slaveAddress << 1) | 1u;
            if (transfer->dataSize == 1U)
            {
                /* The very last byte is always received by means of SW */
                base->MSTCTL  = I2C_MSTCTL_MSTSTART_MASK;
                handle->state = (uint8_t)kReceiveLastDataState;
                return err;
            }
            handle->state = (uint8_t)kReceiveDataState;
        }
        else
        {
            handle->state = (uint8_t)kIdleState;
            err           = kStatus_I2C_UnexpectedState;
            return err;
        }
    }

    switch (handle->state)
    {
        case (uint8_t)kTransmitSubaddrState:
            if ((master_state != (uint32_t)I2C_STAT_MSTCODE_TXREADY) && (0U == start_flag))
            {
                return kStatus_I2C_UnexpectedState;
            }

            base->MSTCTL = start_flag | I2C_MSTCTL_MSTDMA_MASK;

            /* Prepare and submit DMA transfer. */
            DMA_PrepareTransfer(&xferConfig, handle->subaddrBuf, (uint32_t *)address, sizeof(uint8_t),
                                handle->remainingSubaddr, kDMA_MemoryToPeripheral, NULL);
            (void)DMA_SubmitTransfer(handle->dmaHandle, &xferConfig);
            DMA_StartTransfer(handle->dmaHandle);
            handle->remainingSubaddr = 0;
            if (transfer->dataSize != 0U)
            {
                /* There is data to be transferred, if there is write to read turnaround it is necessary to perform
                 * repeated start */
                handle->state = (transfer->direction == kI2C_Read) ? (uint8_t)kStartState : (uint8_t)kTransmitDataState;
            }
            else
            {
                /* No more data, schedule stop condition */
                handle->state = (uint8_t)kStopState;
            }
            break;

        case (uint8_t)kTransmitDataState:
            if ((master_state != (uint32_t)I2C_STAT_MSTCODE_TXREADY) && (0U == start_flag))
            {
                return kStatus_I2C_UnexpectedState;
            }

            base->MSTCTL              = start_flag | I2C_MSTCTL_MSTDMA_MASK;
            handle->remainingBytesDMA = handle->transfer.dataSize;

            I2C_RunDMATransfer(base, handle);

            /* Schedule stop condition */
            handle->state = (uint8_t)kStopState;
            break;

        case (uint8_t)kReceiveDataState:
            if ((master_state != (uint32_t)I2C_STAT_MSTCODE_RXREADY) && (0U == start_flag))
            {
                if (0U == (transfer->flags & (uint32_t)kI2C_TransferNoStartFlag))
                {
                    return kStatus_I2C_UnexpectedState;
                }
            }

            base->MSTCTL              = start_flag | I2C_MSTCTL_MSTDMA_MASK;
            handle->remainingBytesDMA = handle->transfer.dataSize - 1U;

            if ((transfer->flags & (uint32_t)kI2C_TransferNoStartFlag) != 0U)
            {
                /* Read the master data register to avoid the data be read again */
                (void)base->MSTDAT;
            }
            I2C_RunDMATransfer(base, handle);

            /* Schedule reception of last data byte */
            handle->state = (uint8_t)kReceiveLastDataState;
            break;

        case (uint8_t)kReceiveLastDataState:
            if (master_state != (uint32_t)I2C_STAT_MSTCODE_RXREADY)
            {
                return kStatus_I2C_UnexpectedState;
            }

            ((uint8_t *)transfer->data)[transfer->dataSize - 1U] = (uint8_t)base->MSTDAT;
            handle->transferCount++;

            /* No more data expected, issue NACK and STOP right away */
            if (0U == (transfer->flags & (uint32_t)kI2C_TransferNoStopFlag))
            {
                base->MSTCTL = I2C_MSTCTL_MSTSTOP_MASK;
            }
            handle->state = (uint8_t)kWaitForCompletionState;
            break;

        case (uint8_t)kStopState:
            if ((transfer->flags & (uint32_t)kI2C_TransferNoStopFlag) != 0U)
            {
                /* Stop condition is omitted, we are done */
                *isDone       = true;
                handle->state = (uint8_t)kIdleState;
                break;
            }
            /* Send stop condition */
            base->MSTCTL  = I2C_MSTCTL_MSTSTOP_MASK;
            handle->state = (uint8_t)kWaitForCompletionState;
            break;

        case (uint8_t)kWaitForCompletionState:
            *isDone       = true;
            handle->state = (uint8_t)kIdleState;
            break;

        case (uint8_t)kStartState:
        case (uint8_t)kIdleState:
        default:
            /* State machine shall not be invoked again once it enters the idle state */
            err = kStatus_I2C_UnexpectedState;
            break;
    }

    return err;
}

void I2C_MasterTransferDMAHandleIRQ(I2C_Type *base, i2c_master_dma_handle_t *handle)
{
    bool isDone;
    status_t result;

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

    result = I2C_RunTransferStateMachineDMA(base, handle, &isDone);

    if ((result != kStatus_Success) || isDone)
    {
        /* Restore handle to idle state. */
        handle->state = (uint8_t)kIdleState;

        /* Disable internal IRQ enables. */
        I2C_DisableInterrupts(base,
                              I2C_INTSTAT_MSTPENDING_MASK | I2C_INTSTAT_MSTARBLOSS_MASK | I2C_INTSTAT_MSTSTSTPERR_MASK);

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

static void I2C_MasterTransferCallbackDMA(dma_handle_t *handle, void *userData, bool transferDone, uint32_t intmode)
{
    i2c_master_dma_private_handle_t *dmaPrivateHandle;

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

    dmaPrivateHandle = (i2c_master_dma_private_handle_t *)userData;
    I2C_RunDMATransfer(dmaPrivateHandle->base, dmaPrivateHandle->handle);
}

/*!
 * brief Init the I2C handle which is used in transactional functions
 *
 * param base I2C peripheral base address
 * param handle pointer to i2c_master_dma_handle_t structure
 * param callback pointer to user callback function
 * param userData user param passed to the callback function
 * param dmaHandle DMA handle pointer
 */
void I2C_MasterTransferCreateHandleDMA(I2C_Type *base,
                                       i2c_master_dma_handle_t *handle,
                                       i2c_master_dma_transfer_callback_t callback,
                                       void *userData,
                                       dma_handle_t *dmaHandle)
{
    assert(handle != NULL);
    assert(dmaHandle != NULL);

    uint32_t instance;
    i2c_dma_to_flexcomm_t handler;
    handler.i2c_dma_master_handler = I2C_MasterTransferDMAHandleIRQ;

    /* Zero handle. */
    (void)memset(handle, 0, sizeof(*handle));

    /* Look up instance number */
    instance = I2C_GetInstance(base);

    /* Set the user callback and userData. */
    handle->completionCallback = callback;
    handle->userData           = userData;

    FLEXCOMM_SetIRQHandler(base, handler.flexcomm_handler, handle);

    /* Clear internal IRQ enables and enable NVIC IRQ. */
    I2C_DisableInterrupts(base,
                          I2C_INTSTAT_MSTPENDING_MASK | I2C_INTSTAT_MSTARBLOSS_MASK | I2C_INTSTAT_MSTSTSTPERR_MASK);
    (void)EnableIRQ(s_i2cIRQ[instance]);

    /* Set the handle for DMA. */
    handle->dmaHandle = dmaHandle;

    s_dmaPrivateHandle[instance].base   = base;
    s_dmaPrivateHandle[instance].handle = handle;

    DMA_SetCallback(dmaHandle, I2C_MasterTransferCallbackDMA, &s_dmaPrivateHandle[instance]);
}

/*!
 * brief Performs a master dma non-blocking transfer on the I2C bus
 *
 * param base I2C peripheral base address
 * param handle pointer to i2c_master_dma_handle_t structure
 * param xfer pointer to transfer structure of i2c_master_transfer_t
 * retval kStatus_Success Sucessully complete the data transmission.
 * retval kStatus_I2C_Busy Previous transmission still not finished.
 * retval kStatus_I2C_Timeout Transfer error, wait signal timeout.
 * retval kStatus_I2C_ArbitrationLost Transfer error, arbitration lost.
 * retval kStataus_I2C_Nak Transfer error, receive Nak during transfer.
 */
status_t I2C_MasterTransferDMA(I2C_Type *base, i2c_master_dma_handle_t *handle, i2c_master_transfer_t *xfer)
{
    status_t result;

    assert(handle != NULL);
    assert(xfer != NULL);
    assert(xfer->subaddressSize <= sizeof(xfer->subaddress));

    /* Return busy if another transaction is in progress. */
    if (handle->state != (uint8_t)kIdleState)
    {
        return kStatus_I2C_Busy;
    }

    /* Prepare transfer state machine. */
    result = I2C_InitTransferStateMachineDMA(base, handle, xfer);

    /* Clear error flags. */
    I2C_MasterClearStatusFlags(base, I2C_STAT_MSTARBLOSS_MASK | I2C_STAT_MSTSTSTPERR_MASK);

    /* Enable I2C internal IRQ sources */
    I2C_EnableInterrupts(base,
                         I2C_INTSTAT_MSTARBLOSS_MASK | I2C_INTSTAT_MSTSTSTPERR_MASK | I2C_INTSTAT_MSTPENDING_MASK);

    return result;
}

/*!
 * brief Get master transfer status during a dma non-blocking transfer
 *
 * param base I2C peripheral base address
 * param handle pointer to i2c_master_dma_handle_t structure
 * param count Number of bytes transferred so far by the non-blocking transaction.
 */
status_t I2C_MasterTransferGetCountDMA(I2C_Type *base, i2c_master_dma_handle_t *handle, size_t *count)
{
    assert(handle != NULL);

    if (NULL == count)
    {
        return kStatus_InvalidArgument;
    }

    /* Catch when there is not an active transfer. */
    if (handle->state == (uint8_t)kIdleState)
    {
        *count = 0;
        return kStatus_NoTransferInProgress;
    }

    /* There is no necessity to disable interrupts as we read a single integer value */
    *count = handle->transferCount;
    return kStatus_Success;
}

/*!
 * brief Abort a master dma non-blocking transfer in a early time
 *
 * param base I2C peripheral base address
 * param handle pointer to i2c_master_dma_handle_t structure
 */
void I2C_MasterTransferAbortDMA(I2C_Type *base, i2c_master_dma_handle_t *handle)
{
    uint32_t status;
    uint32_t master_state;

    if (handle->state != (uint8_t)kIdleState)
    {
        DMA_AbortTransfer(handle->dmaHandle);

        /* Disable DMA */
        base->MSTCTL = 0;

        /* Disable internal IRQ enables. */
        I2C_DisableInterrupts(base,
                              I2C_INTSTAT_MSTPENDING_MASK | I2C_INTSTAT_MSTARBLOSS_MASK | I2C_INTSTAT_MSTSTSTPERR_MASK);

        /* Wait until module is ready */
        do
        {
            status = I2C_GetStatusFlags(base);
        } while ((status & (uint8_t)I2C_STAT_MSTPENDING_MASK) == 0U);

        /* Clear controller state. */
        I2C_MasterClearStatusFlags(base, I2C_STAT_MSTARBLOSS_MASK | I2C_STAT_MSTSTSTPERR_MASK);

        /* Get the state of the I2C module */
        master_state = (status & I2C_STAT_MSTSTATE_MASK) >> I2C_STAT_MSTSTATE_SHIFT;

        if (master_state != (uint32_t)I2C_STAT_MSTCODE_IDLE)
        {
            /* Send a stop command to finalize the transfer. */
            base->MSTCTL = I2C_MSTCTL_MSTSTOP_MASK;

            /* Wait until module is ready */
            do
            {
                status = I2C_GetStatusFlags(base);
            } while ((status & (uint32_t)I2C_STAT_MSTPENDING_MASK) == 0U);

            /* Clear controller state. */
            I2C_MasterClearStatusFlags(base, I2C_STAT_MSTARBLOSS_MASK | I2C_STAT_MSTSTSTPERR_MASK);
        }

        /* Reset the state to idle. */
        handle->state = (uint8_t)kIdleState;
    }
}
