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/*
* Copyright (c) 2015, Freescale Semiconductor, Inc.
* Copyright 2016-2017 NXP
* All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include "fsl_i2c.h"
/*******************************************************************************
* Definitions
******************************************************************************/
/* Component ID definition, used by tools. */
#ifndef FSL_COMPONENT_ID
#define FSL_COMPONENT_ID "platform.drivers.i2c"
#endif
/*! @brief i2c transfer state. */
enum _i2c_transfer_states
{
kIdleState = 0x0U, /*!< I2C bus idle. */
kCheckAddressState = 0x1U, /*!< 7-bit address check state. */
kSendCommandState = 0x2U, /*!< Send command byte phase. */
kSendDataState = 0x3U, /*!< Send data transfer phase. */
kReceiveDataBeginState = 0x4U, /*!< Receive data transfer phase begin. */
kReceiveDataState = 0x5U, /*!< Receive data transfer phase. */
};
/*! @brief Common sets of flags used by the driver. */
enum _i2c_flag_constants
{
/*! All flags which are cleared by the driver upon starting a transfer. */
#if defined(FSL_FEATURE_I2C_HAS_START_STOP_DETECT) && FSL_FEATURE_I2C_HAS_START_STOP_DETECT
kClearFlags = kI2C_ArbitrationLostFlag | kI2C_IntPendingFlag | kI2C_StartDetectFlag | kI2C_StopDetectFlag,
kIrqFlags = kI2C_GlobalInterruptEnable | kI2C_StartStopDetectInterruptEnable,
#elif defined(FSL_FEATURE_I2C_HAS_STOP_DETECT) && FSL_FEATURE_I2C_HAS_STOP_DETECT
kClearFlags = kI2C_ArbitrationLostFlag | kI2C_IntPendingFlag | kI2C_StopDetectFlag,
kIrqFlags = kI2C_GlobalInterruptEnable | kI2C_StopDetectInterruptEnable,
#else
kClearFlags = kI2C_ArbitrationLostFlag | kI2C_IntPendingFlag,
kIrqFlags = kI2C_GlobalInterruptEnable,
#endif
};
/*! @brief Typedef for interrupt handler. */
typedef void (*i2c_isr_t)(I2C_Type *base, void *i2cHandle);
/*******************************************************************************
* Prototypes
******************************************************************************/
/*!
* @brief Set SCL/SDA hold time, this API receives SCL stop hold time, calculate the
* closest SCL divider and MULT value for the SDA hold time, SCL start and SCL stop
* hold time. To reduce the ROM size, SDA/SCL hold value mapping table is not provided,
* assume SCL divider = SCL stop hold value *2 to get the closest SCL divider value and MULT
* value, then the related SDA hold time, SCL start and SCL stop hold time is used.
*
* @param base I2C peripheral base address.
* @param sourceClock_Hz I2C functional clock frequency in Hertz.
* @param sclStopHoldTime_ns SCL stop hold time in ns.
*/
static void I2C_SetHoldTime(I2C_Type *base, uint32_t sclStopHoldTime_ns, uint32_t sourceClock_Hz);
/*!
* @brief Set up master transfer, send slave address and decide the initial
* transfer state.
*
* @param base I2C peripheral base address.
* @param handle pointer to i2c_master_handle_t structure which stores the transfer state.
* @param xfer pointer to i2c_master_transfer_t structure.
*/
static status_t I2C_InitTransferStateMachine(I2C_Type *base, i2c_master_handle_t *handle, i2c_master_transfer_t *xfer);
/*!
* @brief Check and clear status operation.
*
* @param base I2C peripheral base address.
* @param status current i2c hardware status.
* @retval kStatus_Success No error found.
* @retval kStatus_I2C_ArbitrationLost Transfer error, arbitration lost.
* @retval kStatus_I2C_Nak Received Nak error.
*/
static status_t I2C_CheckAndClearError(I2C_Type *base, uint32_t status);
/*!
* @brief Master run transfer state machine to perform a byte of transfer.
*
* @param base I2C peripheral base address.
* @param handle pointer to i2c_master_handle_t structure which stores the transfer state
* @param isDone input param to get whether the thing is done, true is done
* @retval kStatus_Success No error found.
* @retval kStatus_I2C_ArbitrationLost Transfer error, arbitration lost.
* @retval kStatus_I2C_Nak Received Nak error.
* @retval kStatus_I2C_Timeout Transfer error, wait signal timeout.
*/
static status_t I2C_MasterTransferRunStateMachine(I2C_Type *base, i2c_master_handle_t *handle, bool *isDone);
/*!
* @brief I2C common interrupt handler.
*
* @param base I2C peripheral base address.
* @param handle pointer to i2c_master_handle_t structure which stores the transfer state
*/
static void I2C_TransferCommonIRQHandler(I2C_Type *base, void *handle);
/*******************************************************************************
* Variables
******************************************************************************/
/*! @brief Pointers to i2c bases for each instance. */
I2C_Type *const s_i2cBases[] = I2C_BASE_PTRS;
/*! @brief Pointers to i2c handles for each instance. */
static void *s_i2cHandle[FSL_FEATURE_SOC_I2C_COUNT] = {NULL};
/*! @brief SCL clock divider used to calculate baudrate. */
static const uint16_t s_i2cDividerTable[] = {
20, 22, 24, 26, 28, 30, 34, 40, 28, 32, 36, 40, 44, 48, 56, 68,
48, 56, 64, 72, 80, 88, 104, 128, 80, 96, 112, 128, 144, 160, 192, 240,
160, 192, 224, 256, 288, 320, 384, 480, 320, 384, 448, 512, 576, 640, 768, 960,
640, 768, 896, 1024, 1152, 1280, 1536, 1920, 1280, 1536, 1792, 2048, 2304, 2560, 3072, 3840};
/*! @brief Pointers to i2c IRQ number for each instance. */
static const IRQn_Type s_i2cIrqs[] = I2C_IRQS;
#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
/*! @brief Pointers to i2c clocks for each instance. */
static const clock_ip_name_t s_i2cClocks[] = I2C_CLOCKS;
#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */
/*! @brief Pointer to master IRQ handler for each instance. */
static i2c_isr_t s_i2cMasterIsr;
/*! @brief Pointer to slave IRQ handler for each instance. */
static i2c_isr_t s_i2cSlaveIsr;
/*******************************************************************************
* Codes
******************************************************************************/
/*!
* brief Get instance number for I2C module.
*
* param base I2C peripheral base address.
*/
uint32_t I2C_GetInstance(I2C_Type *base)
{
uint32_t instance;
/* Find the instance index from base address mappings. */
for (instance = 0; instance < ARRAY_SIZE(s_i2cBases); instance++)
{
if (s_i2cBases[instance] == base)
{
break;
}
}
assert(instance < ARRAY_SIZE(s_i2cBases));
return instance;
}
static void I2C_SetHoldTime(I2C_Type *base, uint32_t sclStopHoldTime_ns, uint32_t sourceClock_Hz)
{
uint32_t multiplier;
uint32_t computedSclHoldTime;
uint32_t absError;
uint32_t bestError = UINT32_MAX;
uint32_t bestMult = 0u;
uint32_t bestIcr = 0u;
uint8_t mult;
uint8_t i;
/* Search for the settings with the lowest error. Mult is the MULT field of the I2C_F register,
* and ranges from 0-2. It selects the multiplier factor for the divider. */
/* SDA hold time = bus period (s) * mul * SDA hold value. */
/* SCL start hold time = bus period (s) * mul * SCL start hold value. */
/* SCL stop hold time = bus period (s) * mul * SCL stop hold value. */
for (mult = 0u; (mult <= 2u) && (bestError != 0); ++mult)
{
multiplier = 1u << mult;
/* Scan table to find best match. */
for (i = 0u; i < sizeof(s_i2cDividerTable) / sizeof(s_i2cDividerTable[0]); ++i)
{
/* Assume SCL hold(stop) value = s_i2cDividerTable[i]/2. */
computedSclHoldTime = ((multiplier * s_i2cDividerTable[i]) * 500000U) / (sourceClock_Hz / 1000U);
absError = sclStopHoldTime_ns > computedSclHoldTime ? (sclStopHoldTime_ns - computedSclHoldTime) :
(computedSclHoldTime - sclStopHoldTime_ns);
if (absError < bestError)
{
bestMult = mult;
bestIcr = i;
bestError = absError;
/* If the error is 0, then we can stop searching because we won't find a better match. */
if (absError == 0)
{
break;
}
}
}
}
/* Set frequency register based on best settings. */
base->F = I2C_F_MULT(bestMult) | I2C_F_ICR(bestIcr);
}
static status_t I2C_InitTransferStateMachine(I2C_Type *base, i2c_master_handle_t *handle, i2c_master_transfer_t *xfer)
{
status_t result = kStatus_Success;
i2c_direction_t direction = xfer->direction;
/* Initialize the handle transfer information. */
handle->transfer = *xfer;
/* Save total transfer size. */
handle->transferSize = xfer->dataSize;
/* Initial transfer state. */
if (handle->transfer.subaddressSize > 0)
{
if (xfer->direction == kI2C_Read)
{
direction = kI2C_Write;
}
}
handle->state = kCheckAddressState;
/* Clear all status before transfer. */
I2C_MasterClearStatusFlags(base, kClearFlags);
/* Handle no start option. */
if (handle->transfer.flags & kI2C_TransferNoStartFlag)
{
/* No need to send start flag, directly go to send command or data */
if (handle->transfer.subaddressSize > 0)
{
handle->state = kSendCommandState;
}
else
{
if (direction == kI2C_Write)
{
/* Next state, send data. */
handle->state = kSendDataState;
}
else
{
/* Only support write with no stop signal. */
return kStatus_InvalidArgument;
}
}
/* Wait for TCF bit and manually trigger tx interrupt. */
while (!(base->S & kI2C_TransferCompleteFlag))
{
}
I2C_MasterTransferHandleIRQ(base, handle);
}
/* If repeated start is requested, send repeated start. */
else if (handle->transfer.flags & kI2C_TransferRepeatedStartFlag)
{
result = I2C_MasterRepeatedStart(base, handle->transfer.slaveAddress, direction);
}
else /* For normal transfer, send start. */
{
result = I2C_MasterStart(base, handle->transfer.slaveAddress, direction);
}
return result;
}
static status_t I2C_CheckAndClearError(I2C_Type *base, uint32_t status)
{
status_t result = kStatus_Success;
/* Check arbitration lost. */
if (status & kI2C_ArbitrationLostFlag)
{
/* Clear arbitration lost flag. */
base->S = kI2C_ArbitrationLostFlag;
result = kStatus_I2C_ArbitrationLost;
}
/* Check NAK */
else if (status & kI2C_ReceiveNakFlag)
{
result = kStatus_I2C_Nak;
}
else
{
}
return result;
}
static status_t I2C_MasterTransferRunStateMachine(I2C_Type *base, i2c_master_handle_t *handle, bool *isDone)
{
status_t result = kStatus_Success;
uint32_t statusFlags = base->S;
*isDone = false;
volatile uint8_t dummy = 0;
bool ignoreNak = ((handle->state == kSendDataState) && (handle->transfer.dataSize == 0U)) ||
((handle->state == kReceiveDataState) && (handle->transfer.dataSize == 1U));
/* Add this to avoid build warning. */
dummy++;
/* Check & clear error flags. */
result = I2C_CheckAndClearError(base, statusFlags);
/* Ignore Nak when it's appeared for last byte. */
if ((result == kStatus_I2C_Nak) && ignoreNak)
{
result = kStatus_Success;
}
/* Handle Check address state to check the slave address is Acked in slave
probe application. */
if (handle->state == kCheckAddressState)
{
if (statusFlags & kI2C_ReceiveNakFlag)
{
result = kStatus_I2C_Addr_Nak;
}
else
{
if (handle->transfer.subaddressSize > 0)
{
handle->state = kSendCommandState;
}
else
{
if (handle->transfer.direction == kI2C_Write)
{
/* Next state, send data. */
handle->state = kSendDataState;
}
else
{
/* Next state, receive data begin. */
handle->state = kReceiveDataBeginState;
}
}
}
}
if (result)
{
return result;
}
/* Run state machine. */
switch (handle->state)
{
/* Send I2C command. */
case kSendCommandState:
if (handle->transfer.subaddressSize)
{
handle->transfer.subaddressSize--;
base->D = ((handle->transfer.subaddress) >> (8 * handle->transfer.subaddressSize));
}
else
{
if (handle->transfer.direction == kI2C_Write)
{
/* Send first byte of data. */
if (handle->transfer.dataSize > 0)
{
/* Next state, send data. */
handle->state = kSendDataState;
base->D = *handle->transfer.data;
handle->transfer.data++;
handle->transfer.dataSize--;
}
else
{
*isDone = true;
}
}
else
{
/* Send repeated start and slave address. */
result = I2C_MasterRepeatedStart(base, handle->transfer.slaveAddress, kI2C_Read);
/* Next state, receive data begin. */
handle->state = kReceiveDataBeginState;
}
}
break;
/* Send I2C data. */
case kSendDataState:
/* Send one byte of data. */
if (handle->transfer.dataSize > 0)
{
base->D = *handle->transfer.data;
handle->transfer.data++;
handle->transfer.dataSize--;
}
else
{
*isDone = true;
}
break;
/* Start I2C data receive. */
case kReceiveDataBeginState:
base->C1 &= ~(I2C_C1_TX_MASK | I2C_C1_TXAK_MASK);
/* Send nak at the last receive byte. */
if (handle->transfer.dataSize == 1)
{
base->C1 |= I2C_C1_TXAK_MASK;
}
/* Read dummy to release the bus. */
dummy = base->D;
/* Next state, receive data. */
handle->state = kReceiveDataState;
break;
/* Receive I2C data. */
case kReceiveDataState:
/* Receive one byte of data. */
if (handle->transfer.dataSize--)
{
if (handle->transfer.dataSize == 0)
{
*isDone = true;
/* Send stop if kI2C_TransferNoStop is not asserted. */
if (!(handle->transfer.flags & kI2C_TransferNoStopFlag))
{
result = I2C_MasterStop(base);
}
else
{
base->C1 |= I2C_C1_TX_MASK;
}
}
/* Send NAK at the last receive byte. */
if (handle->transfer.dataSize == 1)
{
base->C1 |= I2C_C1_TXAK_MASK;
}
/* Read the data byte into the transfer buffer. */
*handle->transfer.data = base->D;
handle->transfer.data++;
}
break;
default:
break;
}
return result;
}
static void I2C_TransferCommonIRQHandler(I2C_Type *base, void *handle)
{
/* Check if master interrupt. */
if ((base->S & kI2C_ArbitrationLostFlag) || (base->C1 & I2C_C1_MST_MASK))
{
s_i2cMasterIsr(base, handle);
}
else
{
s_i2cSlaveIsr(base, handle);
}
__DSB();
}
/*!
* brief Initializes the I2C peripheral. Call this API to ungate the I2C clock
* and configure the I2C with master configuration.
*
* note This API should be called at the beginning of the application.
* Otherwise, any operation to the I2C module can cause a hard fault
* because the clock is not enabled. The configuration structure can be custom filled
* or it can be set with default values by using the I2C_MasterGetDefaultConfig().
* After calling this API, the master is ready to transfer.
* This is an example.
* code
* i2c_master_config_t config = {
* .enableMaster = true,
* .enableStopHold = false,
* .highDrive = false,
* .baudRate_Bps = 100000,
* .glitchFilterWidth = 0
* };
* I2C_MasterInit(I2C0, &config, 12000000U);
* endcode
*
* param base I2C base pointer
* param masterConfig A pointer to the master configuration structure
* param srcClock_Hz I2C peripheral clock frequency in Hz
*/
void I2C_MasterInit(I2C_Type *base, const i2c_master_config_t *masterConfig, uint32_t srcClock_Hz)
{
assert(masterConfig && srcClock_Hz);
/* Temporary register for filter read. */
uint8_t fltReg;
#if defined(FSL_FEATURE_I2C_HAS_DOUBLE_BUFFER_ENABLE) && FSL_FEATURE_I2C_HAS_DOUBLE_BUFFER_ENABLE
uint8_t s2Reg;
#endif
#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
/* Enable I2C clock. */
CLOCK_EnableClock(s_i2cClocks[I2C_GetInstance(base)]);
#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */
/* Reset the module. */
base->A1 = 0;
base->F = 0;
base->C1 = 0;
base->S = 0xFFU;
base->C2 = 0;
#if defined(FSL_FEATURE_I2C_HAS_START_STOP_DETECT) && FSL_FEATURE_I2C_HAS_START_STOP_DETECT
base->FLT = 0x50U;
#elif defined(FSL_FEATURE_I2C_HAS_STOP_DETECT) && FSL_FEATURE_I2C_HAS_STOP_DETECT
base->FLT = 0x40U;
#endif
base->RA = 0;
/* Disable I2C prior to configuring it. */
base->C1 &= ~(I2C_C1_IICEN_MASK);
/* Clear all flags. */
I2C_MasterClearStatusFlags(base, kClearFlags);
/* Configure baud rate. */
I2C_MasterSetBaudRate(base, masterConfig->baudRate_Bps, srcClock_Hz);
/* Read out the FLT register. */
fltReg = base->FLT;
#if defined(FSL_FEATURE_I2C_HAS_STOP_HOLD_OFF) && FSL_FEATURE_I2C_HAS_STOP_HOLD_OFF
/* Configure the stop / hold enable. */
fltReg &= ~(I2C_FLT_SHEN_MASK);
fltReg |= I2C_FLT_SHEN(masterConfig->enableStopHold);
#endif
/* Configure the glitch filter value. */
fltReg &= ~(I2C_FLT_FLT_MASK);
fltReg |= I2C_FLT_FLT(masterConfig->glitchFilterWidth);
/* Write the register value back to the filter register. */
base->FLT = fltReg;
/* Enable/Disable double buffering. */
#if defined(FSL_FEATURE_I2C_HAS_DOUBLE_BUFFER_ENABLE) && FSL_FEATURE_I2C_HAS_DOUBLE_BUFFER_ENABLE
s2Reg = base->S2 & (~I2C_S2_DFEN_MASK);
base->S2 = s2Reg | I2C_S2_DFEN(masterConfig->enableDoubleBuffering);
#endif
/* Enable the I2C peripheral based on the configuration. */
base->C1 = I2C_C1_IICEN(masterConfig->enableMaster);
}
/*!
* brief De-initializes the I2C master peripheral. Call this API to gate the I2C clock.
* The I2C master module can't work unless the I2C_MasterInit is called.
* param base I2C base pointer
*/
void I2C_MasterDeinit(I2C_Type *base)
{
/* Disable I2C module. */
I2C_Enable(base, false);
#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
/* Disable I2C clock. */
CLOCK_DisableClock(s_i2cClocks[I2C_GetInstance(base)]);
#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */
}
/*!
* brief Sets the I2C master configuration structure to default values.
*
* The purpose of this API is to get the configuration structure initialized for use in the I2C_MasterConfigure().
* Use the initialized structure unchanged in the I2C_MasterConfigure() or modify
* the structure before calling the I2C_MasterConfigure().
* This is an example.
* code
* i2c_master_config_t config;
* I2C_MasterGetDefaultConfig(&config);
* endcode
* param masterConfig A pointer to the master configuration structure.
*/
void I2C_MasterGetDefaultConfig(i2c_master_config_t *masterConfig)
{
assert(masterConfig);
/* Initializes the configure structure to zero. */
memset(masterConfig, 0, sizeof(*masterConfig));
/* Default baud rate at 100kbps. */
masterConfig->baudRate_Bps = 100000U;
/* Default stop hold enable is disabled. */
#if defined(FSL_FEATURE_I2C_HAS_STOP_HOLD_OFF) && FSL_FEATURE_I2C_HAS_STOP_HOLD_OFF
masterConfig->enableStopHold = false;
#endif
/* Default glitch filter value is no filter. */
masterConfig->glitchFilterWidth = 0U;
/* Default enable double buffering. */
#if defined(FSL_FEATURE_I2C_HAS_DOUBLE_BUFFER_ENABLE) && FSL_FEATURE_I2C_HAS_DOUBLE_BUFFER_ENABLE
masterConfig->enableDoubleBuffering = true;
#endif
/* Enable the I2C peripheral. */
masterConfig->enableMaster = true;
}
/*!
* brief Enables I2C interrupt requests.
*
* param base I2C base pointer
* param mask interrupt source
* The parameter can be combination of the following source if defined:
* arg kI2C_GlobalInterruptEnable
* arg kI2C_StopDetectInterruptEnable/kI2C_StartDetectInterruptEnable
* arg kI2C_SdaTimeoutInterruptEnable
*/
void I2C_EnableInterrupts(I2C_Type *base, uint32_t mask)
{
#ifdef I2C_HAS_STOP_DETECT
uint8_t fltReg;
#endif
if (mask & kI2C_GlobalInterruptEnable)
{
base->C1 |= I2C_C1_IICIE_MASK;
}
#if defined(FSL_FEATURE_I2C_HAS_STOP_DETECT) && FSL_FEATURE_I2C_HAS_STOP_DETECT
if (mask & kI2C_StopDetectInterruptEnable)
{
fltReg = base->FLT;
/* Keep STOPF flag. */
fltReg &= ~I2C_FLT_STOPF_MASK;
/* Stop detect enable. */
fltReg |= I2C_FLT_STOPIE_MASK;
base->FLT = fltReg;
}
#endif /* FSL_FEATURE_I2C_HAS_STOP_DETECT */
#if defined(FSL_FEATURE_I2C_HAS_START_STOP_DETECT) && FSL_FEATURE_I2C_HAS_START_STOP_DETECT
if (mask & kI2C_StartStopDetectInterruptEnable)
{
fltReg = base->FLT;
/* Keep STARTF and STOPF flags. */
fltReg &= ~(I2C_FLT_STOPF_MASK | I2C_FLT_STARTF_MASK);
/* Start and stop detect enable. */
fltReg |= I2C_FLT_SSIE_MASK;
base->FLT = fltReg;
}
#endif /* FSL_FEATURE_I2C_HAS_START_STOP_DETECT */
}
/*!
* brief Disables I2C interrupt requests.
*
* param base I2C base pointer
* param mask interrupt source
* The parameter can be combination of the following source if defined:
* arg kI2C_GlobalInterruptEnable
* arg kI2C_StopDetectInterruptEnable/kI2C_StartDetectInterruptEnable
* arg kI2C_SdaTimeoutInterruptEnable
*/
void I2C_DisableInterrupts(I2C_Type *base, uint32_t mask)
{
if (mask & kI2C_GlobalInterruptEnable)
{
base->C1 &= ~I2C_C1_IICIE_MASK;
}
#if defined(FSL_FEATURE_I2C_HAS_STOP_DETECT) && FSL_FEATURE_I2C_HAS_STOP_DETECT
if (mask & kI2C_StopDetectInterruptEnable)
{
base->FLT &= ~(I2C_FLT_STOPIE_MASK | I2C_FLT_STOPF_MASK);
}
#endif /* FSL_FEATURE_I2C_HAS_STOP_DETECT */
#if defined(FSL_FEATURE_I2C_HAS_START_STOP_DETECT) && FSL_FEATURE_I2C_HAS_START_STOP_DETECT
if (mask & kI2C_StartStopDetectInterruptEnable)
{
base->FLT &= ~(I2C_FLT_SSIE_MASK | I2C_FLT_STOPF_MASK | I2C_FLT_STARTF_MASK);
}
#endif /* FSL_FEATURE_I2C_HAS_START_STOP_DETECT */
}
/*!
* brief Sets the I2C master transfer baud rate.
*
* param base I2C base pointer
* param baudRate_Bps the baud rate value in bps
* param srcClock_Hz Source clock
*/
void I2C_MasterSetBaudRate(I2C_Type *base, uint32_t baudRate_Bps, uint32_t srcClock_Hz)
{
uint32_t multiplier;
uint32_t computedRate;
uint32_t absError;
uint32_t bestError = UINT32_MAX;
uint32_t bestMult = 0u;
uint32_t bestIcr = 0u;
uint8_t mult;
uint8_t i;
/* Search for the settings with the lowest error. Mult is the MULT field of the I2C_F register,
* and ranges from 0-2. It selects the multiplier factor for the divider. */
for (mult = 0u; (mult <= 2u) && (bestError != 0); ++mult)
{
multiplier = 1u << mult;
/* Scan table to find best match. */
for (i = 0u; i < sizeof(s_i2cDividerTable) / sizeof(uint16_t); ++i)
{
computedRate = srcClock_Hz / (multiplier * s_i2cDividerTable[i]);
absError = baudRate_Bps > computedRate ? (baudRate_Bps - computedRate) : (computedRate - baudRate_Bps);
if (absError < bestError)
{
bestMult = mult;
bestIcr = i;
bestError = absError;
/* If the error is 0, then we can stop searching because we won't find a better match. */
if (absError == 0)
{
break;
}
}
}
}
/* Set frequency register based on best settings. */
base->F = I2C_F_MULT(bestMult) | I2C_F_ICR(bestIcr);
}
/*!
* brief Sends a START on the I2C bus.
*
* This function is used to initiate a new master mode transfer by sending the START signal.
* The slave address is sent following the I2C START signal.
*
* param base I2C peripheral base pointer
* param address 7-bit slave device address.
* param direction Master transfer directions(transmit/receive).
* retval kStatus_Success Successfully send the start signal.
* retval kStatus_I2C_Busy Current bus is busy.
*/
status_t I2C_MasterStart(I2C_Type *base, uint8_t address, i2c_direction_t direction)
{
status_t result = kStatus_Success;
uint32_t statusFlags = I2C_MasterGetStatusFlags(base);
/* Return an error if the bus is already in use. */
if (statusFlags & kI2C_BusBusyFlag)
{
result = kStatus_I2C_Busy;
}
else
{
/* Send the START signal. */
base->C1 |= I2C_C1_MST_MASK | I2C_C1_TX_MASK;
#if defined(FSL_FEATURE_I2C_HAS_DOUBLE_BUFFERING) && FSL_FEATURE_I2C_HAS_DOUBLE_BUFFERING
#if I2C_WAIT_TIMEOUT
uint32_t waitTimes = I2C_WAIT_TIMEOUT;
while ((!(base->S2 & I2C_S2_EMPTY_MASK)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
while (!(base->S2 & I2C_S2_EMPTY_MASK))
{
}
#endif
#endif /* FSL_FEATURE_I2C_HAS_DOUBLE_BUFFERING */
base->D = (((uint32_t)address) << 1U | ((direction == kI2C_Read) ? 1U : 0U));
}
return result;
}
/*!
* brief Sends a REPEATED START on the I2C bus.
*
* param base I2C peripheral base pointer
* param address 7-bit slave device address.
* param direction Master transfer directions(transmit/receive).
* retval kStatus_Success Successfully send the start signal.
* retval kStatus_I2C_Busy Current bus is busy but not occupied by current I2C master.
*/
status_t I2C_MasterRepeatedStart(I2C_Type *base, uint8_t address, i2c_direction_t direction)
{
status_t result = kStatus_Success;
uint8_t savedMult;
uint32_t statusFlags = I2C_MasterGetStatusFlags(base);
uint8_t timeDelay = 6;
/* Return an error if the bus is already in use, but not by us. */
if ((statusFlags & kI2C_BusBusyFlag) && ((base->C1 & I2C_C1_MST_MASK) == 0))
{
result = kStatus_I2C_Busy;
}
else
{
savedMult = base->F;
base->F = savedMult & (~I2C_F_MULT_MASK);
/* We are already in a transfer, so send a repeated start. */
base->C1 |= I2C_C1_RSTA_MASK | I2C_C1_TX_MASK;
/* Restore the multiplier factor. */
base->F = savedMult;
/* Add some delay to wait the Re-Start signal. */
while (timeDelay--)
{
__NOP();
}
#if defined(FSL_FEATURE_I2C_HAS_DOUBLE_BUFFERING) && FSL_FEATURE_I2C_HAS_DOUBLE_BUFFERING
#if I2C_WAIT_TIMEOUT
uint32_t waitTimes = I2C_WAIT_TIMEOUT;
while ((!(base->S2 & I2C_S2_EMPTY_MASK)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
while (!(base->S2 & I2C_S2_EMPTY_MASK))
{
}
#endif
#endif /* FSL_FEATURE_I2C_HAS_DOUBLE_BUFFERING */
base->D = (((uint32_t)address) << 1U | ((direction == kI2C_Read) ? 1U : 0U));
}
return result;
}
/*!
* brief Sends a STOP signal on the I2C bus.
*
* retval kStatus_Success Successfully send the stop signal.
* retval kStatus_I2C_Timeout Send stop signal failed, timeout.
*/
status_t I2C_MasterStop(I2C_Type *base)
{
status_t result = kStatus_Success;
/* Issue the STOP command on the bus. */
base->C1 &= ~(I2C_C1_MST_MASK | I2C_C1_TX_MASK | I2C_C1_TXAK_MASK);
#if I2C_WAIT_TIMEOUT
uint32_t waitTimes = I2C_WAIT_TIMEOUT;
/* Wait until bus not busy. */
while ((base->S & kI2C_BusBusyFlag) && (--waitTimes))
{
}
if (waitTimes == 0)
{
result = kStatus_I2C_Timeout;
}
#else
/* Wait until data transfer complete. */
while (base->S & kI2C_BusBusyFlag)
{
}
#endif
return result;
}
/*!
* brief Gets the I2C status flags.
*
* param base I2C base pointer
* return status flag, use status flag to AND #_i2c_flags to get the related status.
*/
uint32_t I2C_MasterGetStatusFlags(I2C_Type *base)
{
uint32_t statusFlags = base->S;
#ifdef I2C_HAS_STOP_DETECT
/* Look up the STOPF bit from the filter register. */
if (base->FLT & I2C_FLT_STOPF_MASK)
{
statusFlags |= kI2C_StopDetectFlag;
}
#endif
#if defined(FSL_FEATURE_I2C_HAS_START_STOP_DETECT) && FSL_FEATURE_I2C_HAS_START_STOP_DETECT
/* Look up the STARTF bit from the filter register. */
if (base->FLT & I2C_FLT_STARTF_MASK)
{
statusFlags |= kI2C_StartDetectFlag;
}
#endif /* FSL_FEATURE_I2C_HAS_START_STOP_DETECT */
return statusFlags;
}
/*!
* brief Performs a polling send transaction on the I2C bus.
*
* param base The I2C peripheral base pointer.
* param txBuff The pointer to the data to be transferred.
* param txSize The length in bytes of the data to be transferred.
* param flags Transfer control flag to decide whether need to send a stop, use kI2C_TransferDefaultFlag
* to issue a stop and kI2C_TransferNoStop to not send a stop.
* retval kStatus_Success Successfully complete the data transmission.
* retval kStatus_I2C_ArbitrationLost Transfer error, arbitration lost.
* retval kStataus_I2C_Nak Transfer error, receive NAK during transfer.
*/
status_t I2C_MasterWriteBlocking(I2C_Type *base, const uint8_t *txBuff, size_t txSize, uint32_t flags)
{
status_t result = kStatus_Success;
uint8_t statusFlags = 0;
#if I2C_WAIT_TIMEOUT
uint32_t waitTimes = I2C_WAIT_TIMEOUT;
/* Wait until the data register is ready for transmit. */
while ((!(base->S & kI2C_TransferCompleteFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait until the data register is ready for transmit. */
while (!(base->S & kI2C_TransferCompleteFlag))
{
}
#endif
/* Clear the IICIF flag. */
base->S = kI2C_IntPendingFlag;
/* Setup the I2C peripheral to transmit data. */
base->C1 |= I2C_C1_TX_MASK;
while (txSize--)
{
/* Send a byte of data. */
base->D = *txBuff++;
#if I2C_WAIT_TIMEOUT
waitTimes = I2C_WAIT_TIMEOUT;
/* Wait until data transfer complete. */
while ((!(base->S & kI2C_IntPendingFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait until data transfer complete. */
while (!(base->S & kI2C_IntPendingFlag))
{
}
#endif
statusFlags = base->S;
/* Clear the IICIF flag. */
base->S = kI2C_IntPendingFlag;
/* Check if arbitration lost or no acknowledgement (NAK), return failure status. */
if (statusFlags & kI2C_ArbitrationLostFlag)
{
base->S = kI2C_ArbitrationLostFlag;
result = kStatus_I2C_ArbitrationLost;
}
if ((statusFlags & kI2C_ReceiveNakFlag) && txSize)
{
base->S = kI2C_ReceiveNakFlag;
result = kStatus_I2C_Nak;
}
if (result != kStatus_Success)
{
/* Breaking out of the send loop. */
break;
}
}
if (((result == kStatus_Success) && (!(flags & kI2C_TransferNoStopFlag))) || (result == kStatus_I2C_Nak))
{
/* Clear the IICIF flag. */
base->S = kI2C_IntPendingFlag;
/* Send stop. */
result = I2C_MasterStop(base);
}
return result;
}
/*!
* brief Performs a polling receive transaction on the I2C bus.
*
* note The I2C_MasterReadBlocking function stops the bus before reading the final byte.
* Without stopping the bus prior for the final read, the bus issues another read, resulting
* in garbage data being read into the data register.
*
* param base I2C peripheral base pointer.
* param rxBuff The pointer to the data to store the received data.
* param rxSize The length in bytes of the data to be received.
* param flags Transfer control flag to decide whether need to send a stop, use kI2C_TransferDefaultFlag
* to issue a stop and kI2C_TransferNoStop to not send a stop.
* retval kStatus_Success Successfully complete the data transmission.
* retval kStatus_I2C_Timeout Send stop signal failed, timeout.
*/
status_t I2C_MasterReadBlocking(I2C_Type *base, uint8_t *rxBuff, size_t rxSize, uint32_t flags)
{
status_t result = kStatus_Success;
volatile uint8_t dummy = 0;
/* Add this to avoid build warning. */
dummy++;
#if I2C_WAIT_TIMEOUT
uint32_t waitTimes = I2C_WAIT_TIMEOUT;
/* Wait until the data register is ready for transmit. */
while ((!(base->S & kI2C_TransferCompleteFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait until the data register is ready for transmit. */
while (!(base->S & kI2C_TransferCompleteFlag))
{
}
#endif
/* Clear the IICIF flag. */
base->S = kI2C_IntPendingFlag;
/* Setup the I2C peripheral to receive data. */
base->C1 &= ~(I2C_C1_TX_MASK | I2C_C1_TXAK_MASK);
/* If rxSize equals 1, configure to send NAK. */
if (rxSize == 1)
{
/* Issue NACK on read. */
base->C1 |= I2C_C1_TXAK_MASK;
}
/* Do dummy read. */
dummy = base->D;
while ((rxSize--))
{
#if I2C_WAIT_TIMEOUT
waitTimes = I2C_WAIT_TIMEOUT;
/* Wait until data transfer complete. */
while ((!(base->S & kI2C_IntPendingFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait until data transfer complete. */
while (!(base->S & kI2C_IntPendingFlag))
{
}
#endif
/* Clear the IICIF flag. */
base->S = kI2C_IntPendingFlag;
/* Single byte use case. */
if (rxSize == 0)
{
if (!(flags & kI2C_TransferNoStopFlag))
{
/* Issue STOP command before reading last byte. */
result = I2C_MasterStop(base);
}
else
{
/* Change direction to Tx to avoid extra clocks. */
base->C1 |= I2C_C1_TX_MASK;
}
}
if (rxSize == 1)
{
/* Issue NACK on read. */
base->C1 |= I2C_C1_TXAK_MASK;
}
/* Read from the data register. */
*rxBuff++ = base->D;
}
return result;
}
/*!
* brief Performs a master polling transfer on the I2C bus.
*
* note The API does not return until the transfer succeeds or fails due
* to arbitration lost or receiving a NAK.
*
* param base I2C peripheral base address.
* param xfer Pointer to the transfer structure.
* retval kStatus_Success Successfully 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_MasterTransferBlocking(I2C_Type *base, i2c_master_transfer_t *xfer)
{
assert(xfer);
i2c_direction_t direction = xfer->direction;
status_t result = kStatus_Success;
/* Clear all status before transfer. */
I2C_MasterClearStatusFlags(base, kClearFlags);
#if I2C_WAIT_TIMEOUT
uint32_t waitTimes = I2C_WAIT_TIMEOUT;
/* Wait until the data register is ready for transmit. */
while ((!(base->S & kI2C_TransferCompleteFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait until the data register is ready for transmit. */
while (!(base->S & kI2C_TransferCompleteFlag))
{
}
#endif
/* Change to send write address when it's a read operation with command. */
if ((xfer->subaddressSize > 0) && (xfer->direction == kI2C_Read))
{
direction = kI2C_Write;
}
/* Handle no start option, only support write with no start signal. */
if (xfer->flags & kI2C_TransferNoStartFlag)
{
if (direction == kI2C_Read)
{
return kStatus_InvalidArgument;
}
}
/* If repeated start is requested, send repeated start. */
else if (xfer->flags & kI2C_TransferRepeatedStartFlag)
{
result = I2C_MasterRepeatedStart(base, xfer->slaveAddress, direction);
}
else /* For normal transfer, send start. */
{
result = I2C_MasterStart(base, xfer->slaveAddress, direction);
}
if (!(xfer->flags & kI2C_TransferNoStartFlag))
{
/* Return if error. */
if (result)
{
return result;
}
#if I2C_WAIT_TIMEOUT
waitTimes = I2C_WAIT_TIMEOUT;
/* Wait until data transfer complete. */
while ((!(base->S & kI2C_IntPendingFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait until data transfer complete. */
while (!(base->S & kI2C_IntPendingFlag))
{
}
#endif
/* Check if there's transfer error. */
result = I2C_CheckAndClearError(base, base->S);
/* Return if error. */
if (result)
{
if (result == kStatus_I2C_Nak)
{
result = kStatus_I2C_Addr_Nak;
I2C_MasterStop(base);
}
return result;
}
}
/* Send subaddress. */
if (xfer->subaddressSize)
{
do
{
/* Clear interrupt pending flag. */
base->S = kI2C_IntPendingFlag;
xfer->subaddressSize--;
base->D = ((xfer->subaddress) >> (8 * xfer->subaddressSize));
#if I2C_WAIT_TIMEOUT
waitTimes = I2C_WAIT_TIMEOUT;
/* Wait until data transfer complete. */
while ((!(base->S & kI2C_IntPendingFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait until data transfer complete. */
while (!(base->S & kI2C_IntPendingFlag))
{
}
#endif
/* Check if there's transfer error. */
result = I2C_CheckAndClearError(base, base->S);
if (result)
{
if (result == kStatus_I2C_Nak)
{
I2C_MasterStop(base);
}
return result;
}
} while (xfer->subaddressSize > 0);
if (xfer->direction == kI2C_Read)
{
/* Clear pending flag. */
base->S = kI2C_IntPendingFlag;
/* Send repeated start and slave address. */
result = I2C_MasterRepeatedStart(base, xfer->slaveAddress, kI2C_Read);
/* Return if error. */
if (result)
{
return result;
}
#if I2C_WAIT_TIMEOUT
waitTimes = I2C_WAIT_TIMEOUT;
/* Wait until data transfer complete. */
while ((!(base->S & kI2C_IntPendingFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait until data transfer complete. */
while (!(base->S & kI2C_IntPendingFlag))
{
}
#endif
/* Check if there's transfer error. */
result = I2C_CheckAndClearError(base, base->S);
if (result)
{
if (result == kStatus_I2C_Nak)
{
result = kStatus_I2C_Addr_Nak;
I2C_MasterStop(base);
}
return result;
}
}
}
/* Transmit data. */
if (xfer->direction == kI2C_Write)
{
if (xfer->dataSize > 0)
{
/* Send Data. */
result = I2C_MasterWriteBlocking(base, xfer->data, xfer->dataSize, xfer->flags);
}
else if (!(xfer->flags & kI2C_TransferNoStopFlag))
{
/* Send stop. */
result = I2C_MasterStop(base);
}
else
{
}
}
/* Receive Data. */
if ((xfer->direction == kI2C_Read) && (xfer->dataSize > 0))
{
result = I2C_MasterReadBlocking(base, xfer->data, xfer->dataSize, xfer->flags);
}
return result;
}
/*!
* brief Initializes the I2C handle which is used in transactional functions.
*
* param base I2C base pointer.
* param handle pointer to i2c_master_handle_t structure to store the transfer state.
* param callback pointer to user callback function.
* param userData user parameter passed to the callback function.
*/
void I2C_MasterTransferCreateHandle(I2C_Type *base,
i2c_master_handle_t *handle,
i2c_master_transfer_callback_t callback,
void *userData)
{
assert(handle);
uint32_t instance = I2C_GetInstance(base);
/* Zero handle. */
memset(handle, 0, sizeof(*handle));
/* Set callback and userData. */
handle->completionCallback = callback;
handle->userData = userData;
/* Save the context in global variables to support the double weak mechanism. */
s_i2cHandle[instance] = handle;
/* Save master interrupt handler. */
s_i2cMasterIsr = I2C_MasterTransferHandleIRQ;
/* Enable NVIC interrupt. */
EnableIRQ(s_i2cIrqs[instance]);
}
/*!
* brief Performs a master interrupt non-blocking transfer on the I2C bus.
*
* note Calling the API returns immediately after transfer initiates. The user needs
* to call I2C_MasterGetTransferCount to poll the transfer status to check whether
* the transfer is finished. If the return status is not kStatus_I2C_Busy, the transfer
* is finished.
*
* param base I2C base pointer.
* param handle pointer to i2c_master_handle_t structure which stores the transfer state.
* param xfer pointer to i2c_master_transfer_t structure.
* retval kStatus_Success Successfully start the data transmission.
* retval kStatus_I2C_Busy Previous transmission still not finished.
* retval kStatus_I2C_Timeout Transfer error, wait signal timeout.
*/
status_t I2C_MasterTransferNonBlocking(I2C_Type *base, i2c_master_handle_t *handle, i2c_master_transfer_t *xfer)
{
assert(handle);
assert(xfer);
status_t result = kStatus_Success;
/* Check if the I2C bus is idle - if not return busy status. */
if (handle->state != kIdleState)
{
result = kStatus_I2C_Busy;
}
else
{
/* Start up the master transfer state machine. */
result = I2C_InitTransferStateMachine(base, handle, xfer);
if (result == kStatus_Success)
{
/* Enable the I2C interrupts. */
I2C_EnableInterrupts(base, kI2C_GlobalInterruptEnable);
}
}
return result;
}
/*!
* brief Aborts an interrupt non-blocking transfer early.
*
* note This API can be called at any time when an interrupt non-blocking transfer initiates
* to abort the transfer early.
*
* param base I2C base pointer.
* param handle pointer to i2c_master_handle_t structure which stores the transfer state
* retval kStatus_I2C_Timeout Timeout during polling flag.
* retval kStatus_Success Successfully abort the transfer.
*/
status_t I2C_MasterTransferAbort(I2C_Type *base, i2c_master_handle_t *handle)
{
assert(handle);
volatile uint8_t dummy = 0;
#if I2C_WAIT_TIMEOUT
uint32_t waitTimes = I2C_WAIT_TIMEOUT;
#endif
/* Add this to avoid build warning. */
dummy++;
/* Disable interrupt. */
I2C_DisableInterrupts(base, kI2C_GlobalInterruptEnable);
/* Reset the state to idle. */
handle->state = kIdleState;
/* If the bus is already in use, but not by us */
if (!(base->C1 & I2C_C1_MST_MASK))
{
return kStatus_I2C_Busy;
}
/* Send STOP signal. */
if (handle->transfer.direction == kI2C_Read)
{
base->C1 |= I2C_C1_TXAK_MASK;
#if I2C_WAIT_TIMEOUT
/* Wait until data transfer complete. */
while ((!(base->S & kI2C_IntPendingFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait until data transfer complete. */
while (!(base->S & kI2C_IntPendingFlag))
{
}
#endif
base->S = kI2C_IntPendingFlag;
base->C1 &= ~(I2C_C1_MST_MASK | I2C_C1_TX_MASK | I2C_C1_TXAK_MASK);
dummy = base->D;
}
else
{
#if I2C_WAIT_TIMEOUT
/* Wait until data transfer complete. */
while ((!(base->S & kI2C_IntPendingFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait until data transfer complete. */
while (!(base->S & kI2C_IntPendingFlag))
{
}
#endif
base->S = kI2C_IntPendingFlag;
base->C1 &= ~(I2C_C1_MST_MASK | I2C_C1_TX_MASK | I2C_C1_TXAK_MASK);
}
return kStatus_Success;
}
/*!
* brief Gets the master transfer status during a interrupt non-blocking transfer.
*
* param base I2C base pointer.
* param handle pointer to i2c_master_handle_t structure which stores the transfer state.
* param count Number of bytes transferred so far by the non-blocking transaction.
* retval kStatus_InvalidArgument count is Invalid.
* retval kStatus_Success Successfully return the count.
*/
status_t I2C_MasterTransferGetCount(I2C_Type *base, i2c_master_handle_t *handle, size_t *count)
{
assert(handle);
if (!count)
{
return kStatus_InvalidArgument;
}
*count = handle->transferSize - handle->transfer.dataSize;
return kStatus_Success;
}
/*!
* brief Master interrupt handler.
*
* param base I2C base pointer.
* param i2cHandle pointer to i2c_master_handle_t structure.
*/
void I2C_MasterTransferHandleIRQ(I2C_Type *base, void *i2cHandle)
{
assert(i2cHandle);
i2c_master_handle_t *handle = (i2c_master_handle_t *)i2cHandle;
status_t result = kStatus_Success;
bool isDone;
/* Clear the interrupt flag. */
base->S = kI2C_IntPendingFlag;
/* Check transfer complete flag. */
result = I2C_MasterTransferRunStateMachine(base, handle, &isDone);
if (isDone || result)
{
/* Send stop command if transfer done or received Nak. */
if ((!(handle->transfer.flags & kI2C_TransferNoStopFlag)) || (result == kStatus_I2C_Nak) ||
(result == kStatus_I2C_Addr_Nak))
{
/* Ensure stop command is a need. */
if ((base->C1 & I2C_C1_MST_MASK))
{
if (I2C_MasterStop(base) != kStatus_Success)
{
result = kStatus_I2C_Timeout;
}
}
}
/* Restore handle to idle state. */
handle->state = kIdleState;
/* Disable interrupt. */
I2C_DisableInterrupts(base, kI2C_GlobalInterruptEnable);
/* Call the callback function after the function has completed. */
if (handle->completionCallback)
{
handle->completionCallback(base, handle, result, handle->userData);
}
}
}
/*!
* brief Initializes the I2C peripheral. Call this API to ungate the I2C clock
* and initialize the I2C with the slave configuration.
*
* note This API should be called at the beginning of the application.
* Otherwise, any operation to the I2C module can cause a hard fault
* because the clock is not enabled. The configuration structure can partly be set
* with default values by I2C_SlaveGetDefaultConfig() or it can be custom filled by the user.
* This is an example.
* code
* i2c_slave_config_t config = {
* .enableSlave = true,
* .enableGeneralCall = false,
* .addressingMode = kI2C_Address7bit,
* .slaveAddress = 0x1DU,
* .enableWakeUp = false,
* .enablehighDrive = false,
* .enableBaudRateCtl = false,
* .sclStopHoldTime_ns = 4000
* };
* I2C_SlaveInit(I2C0, &config, 12000000U);
* endcode
*
* param base I2C base pointer
* param slaveConfig A pointer to the slave configuration structure
* param srcClock_Hz I2C peripheral clock frequency in Hz
*/
void I2C_SlaveInit(I2C_Type *base, const i2c_slave_config_t *slaveConfig, uint32_t srcClock_Hz)
{
assert(slaveConfig);
uint8_t tmpReg;
#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
CLOCK_EnableClock(s_i2cClocks[I2C_GetInstance(base)]);
#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */
/* Reset the module. */
base->A1 = 0;
base->F = 0;
base->C1 = 0;
base->S = 0xFFU;
base->C2 = 0;
#if defined(FSL_FEATURE_I2C_HAS_START_STOP_DETECT) && FSL_FEATURE_I2C_HAS_START_STOP_DETECT
base->FLT = 0x50U;
#elif defined(FSL_FEATURE_I2C_HAS_STOP_DETECT) && FSL_FEATURE_I2C_HAS_STOP_DETECT
base->FLT = 0x40U;
#endif
base->RA = 0;
/* Configure addressing mode. */
switch (slaveConfig->addressingMode)
{
case kI2C_Address7bit:
base->A1 = ((uint32_t)(slaveConfig->slaveAddress)) << 1U;
break;
case kI2C_RangeMatch:
assert(slaveConfig->slaveAddress < slaveConfig->upperAddress);
base->A1 = ((uint32_t)(slaveConfig->slaveAddress)) << 1U;
base->RA = ((uint32_t)(slaveConfig->upperAddress)) << 1U;
base->C2 |= I2C_C2_RMEN_MASK;
break;
default:
break;
}
/* Configure low power wake up feature. */
tmpReg = base->C1;
tmpReg &= ~I2C_C1_WUEN_MASK;
base->C1 = tmpReg | I2C_C1_WUEN(slaveConfig->enableWakeUp) | I2C_C1_IICEN(slaveConfig->enableSlave);
/* Configure general call & baud rate control. */
tmpReg = base->C2;
tmpReg &= ~(I2C_C2_SBRC_MASK | I2C_C2_GCAEN_MASK);
tmpReg |= I2C_C2_SBRC(slaveConfig->enableBaudRateCtl) | I2C_C2_GCAEN(slaveConfig->enableGeneralCall);
base->C2 = tmpReg;
/* Enable/Disable double buffering. */
#if defined(FSL_FEATURE_I2C_HAS_DOUBLE_BUFFER_ENABLE) && FSL_FEATURE_I2C_HAS_DOUBLE_BUFFER_ENABLE
tmpReg = base->S2 & (~I2C_S2_DFEN_MASK);
base->S2 = tmpReg | I2C_S2_DFEN(slaveConfig->enableDoubleBuffering);
#endif
/* Set hold time. */
I2C_SetHoldTime(base, slaveConfig->sclStopHoldTime_ns, srcClock_Hz);
}
/*!
* brief De-initializes the I2C slave peripheral. Calling this API gates the I2C clock.
* The I2C slave module can't work unless the I2C_SlaveInit is called to enable the clock.
* param base I2C base pointer
*/
void I2C_SlaveDeinit(I2C_Type *base)
{
/* Disable I2C module. */
I2C_Enable(base, false);
#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
/* Disable I2C clock. */
CLOCK_DisableClock(s_i2cClocks[I2C_GetInstance(base)]);
#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */
}
/*!
* brief Sets the I2C slave configuration structure to default values.
*
* The purpose of this API is to get the configuration structure initialized for use in the I2C_SlaveConfigure().
* Modify fields of the structure before calling the I2C_SlaveConfigure().
* This is an example.
* code
* i2c_slave_config_t config;
* I2C_SlaveGetDefaultConfig(&config);
* endcode
* param slaveConfig A pointer to the slave configuration structure.
*/
void I2C_SlaveGetDefaultConfig(i2c_slave_config_t *slaveConfig)
{
assert(slaveConfig);
/* Initializes the configure structure to zero. */
memset(slaveConfig, 0, sizeof(*slaveConfig));
/* By default slave is addressed with 7-bit address. */
slaveConfig->addressingMode = kI2C_Address7bit;
/* General call mode is disabled by default. */
slaveConfig->enableGeneralCall = false;
/* Slave address match waking up MCU from low power mode is disabled. */
slaveConfig->enableWakeUp = false;
/* Independent slave mode baud rate at maximum frequency is disabled. */
slaveConfig->enableBaudRateCtl = false;
/* Default enable double buffering. */
#if defined(FSL_FEATURE_I2C_HAS_DOUBLE_BUFFER_ENABLE) && FSL_FEATURE_I2C_HAS_DOUBLE_BUFFER_ENABLE
slaveConfig->enableDoubleBuffering = true;
#endif
/* Set default SCL stop hold time to 4us which is minimum requirement in I2C spec. */
slaveConfig->sclStopHoldTime_ns = 4000;
/* Enable the I2C peripheral. */
slaveConfig->enableSlave = true;
}
/*!
* brief Performs a polling send transaction on the I2C bus.
*
* param base The I2C peripheral base pointer.
* param txBuff The pointer to the data to be transferred.
* param txSize The length in bytes of the data to be transferred.
* retval kStatus_Success Successfully complete the data transmission.
* retval kStatus_I2C_ArbitrationLost Transfer error, arbitration lost.
* retval kStataus_I2C_Nak Transfer error, receive NAK during transfer.
*/
status_t I2C_SlaveWriteBlocking(I2C_Type *base, const uint8_t *txBuff, size_t txSize)
{
status_t result = kStatus_Success;
volatile uint8_t dummy = 0;
/* Add this to avoid build warning. */
dummy++;
#if defined(FSL_FEATURE_I2C_HAS_START_STOP_DETECT) && FSL_FEATURE_I2C_HAS_START_STOP_DETECT
/* Check start flag. */
while (!(base->FLT & I2C_FLT_STARTF_MASK))
{
}
/* Clear STARTF flag. */
base->FLT |= I2C_FLT_STARTF_MASK;
/* Clear the IICIF flag. */
base->S = kI2C_IntPendingFlag;
#endif /* FSL_FEATURE_I2C_HAS_START_STOP_DETECT */
#if I2C_WAIT_TIMEOUT
uint32_t waitTimes = I2C_WAIT_TIMEOUT;
/* Wait until data transfer complete. */
while ((!(base->S & kI2C_AddressMatchFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait for address match flag. */
while (!(base->S & kI2C_AddressMatchFlag))
{
}
#endif
/* Read dummy to release bus. */
dummy = base->D;
result = I2C_MasterWriteBlocking(base, txBuff, txSize, kI2C_TransferDefaultFlag);
/* Switch to receive mode. */
base->C1 &= ~(I2C_C1_TX_MASK | I2C_C1_TXAK_MASK);
/* Read dummy to release bus. */
dummy = base->D;
return result;
}
/*!
* brief Performs a polling receive transaction on the I2C bus.
*
* param base I2C peripheral base pointer.
* param rxBuff The pointer to the data to store the received data.
* param rxSize The length in bytes of the data to be received.
* retval kStatus_Success Successfully complete data receive.
* retval kStatus_I2C_Timeout Wait status flag timeout.
*/
status_t I2C_SlaveReadBlocking(I2C_Type *base, uint8_t *rxBuff, size_t rxSize)
{
status_t result = kStatus_Success;
volatile uint8_t dummy = 0;
/* Add this to avoid build warning. */
dummy++;
/* Wait until address match. */
#if defined(FSL_FEATURE_I2C_HAS_START_STOP_DETECT) && FSL_FEATURE_I2C_HAS_START_STOP_DETECT
/* Check start flag. */
while (!(base->FLT & I2C_FLT_STARTF_MASK))
{
}
/* Clear STARTF flag. */
base->FLT |= I2C_FLT_STARTF_MASK;
/* Clear the IICIF flag. */
base->S = kI2C_IntPendingFlag;
#endif /* FSL_FEATURE_I2C_HAS_START_STOP_DETECT */
#if I2C_WAIT_TIMEOUT
uint32_t waitTimes = I2C_WAIT_TIMEOUT;
/* Wait for address match and int pending flag. */
while ((!(base->S & kI2C_AddressMatchFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
waitTimes = I2C_WAIT_TIMEOUT;
while ((!(base->S & kI2C_IntPendingFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait for address match and int pending flag. */
while (!(base->S & kI2C_AddressMatchFlag))
{
}
while (!(base->S & kI2C_IntPendingFlag))
{
}
#endif
/* Read dummy to release bus. */
dummy = base->D;
/* Clear the IICIF flag. */
base->S = kI2C_IntPendingFlag;
/* Setup the I2C peripheral to receive data. */
base->C1 &= ~(I2C_C1_TX_MASK);
while (rxSize--)
{
#if I2C_WAIT_TIMEOUT
waitTimes = I2C_WAIT_TIMEOUT;
/* Wait until data transfer complete. */
while ((!(base->S & kI2C_IntPendingFlag)) && (--waitTimes))
{
}
if (waitTimes == 0)
{
return kStatus_I2C_Timeout;
}
#else
/* Wait until data transfer complete. */
while (!(base->S & kI2C_IntPendingFlag))
{
}
#endif
/* Clear the IICIF flag. */
base->S = kI2C_IntPendingFlag;
/* Read from the data register. */
*rxBuff++ = base->D;
}
return result;
}
/*!
* brief Initializes the I2C handle which is used in transactional functions.
*
* param base I2C base pointer.
* param handle pointer to i2c_slave_handle_t structure to store the transfer state.
* param callback pointer to user callback function.
* param userData user parameter passed to the callback function.
*/
void I2C_SlaveTransferCreateHandle(I2C_Type *base,
i2c_slave_handle_t *handle,
i2c_slave_transfer_callback_t callback,
void *userData)
{
assert(handle);
uint32_t instance = I2C_GetInstance(base);
/* Zero handle. */
memset(handle, 0, sizeof(*handle));
/* Set callback and userData. */
handle->callback = callback;
handle->userData = userData;
/* Save the context in global variables to support the double weak mechanism. */
s_i2cHandle[instance] = handle;
/* Save slave interrupt handler. */
s_i2cSlaveIsr = I2C_SlaveTransferHandleIRQ;
/* Enable NVIC interrupt. */
EnableIRQ(s_i2cIrqs[instance]);
}
/*!
* brief Starts accepting slave transfers.
*
* Call this API after calling the I2C_SlaveInit() and I2C_SlaveTransferCreateHandle() to start processing
* transactions driven by an I2C master. The slave monitors the I2C bus and passes events to the
* callback that was passed into the call to I2C_SlaveTransferCreateHandle(). The callback is always invoked
* from the interrupt context.
*
* The set of events received by the callback is customizable. To do so, set the a eventMask parameter to
* the OR'd combination of #i2c_slave_transfer_event_t enumerators for the events you wish to receive.
* The #kI2C_SlaveTransmitEvent and #kLPI2C_SlaveReceiveEvent events are always enabled and do not need
* to be included in the mask. Alternatively, pass 0 to get a default set of only the transmit and
* receive events that are always enabled. In addition, the #kI2C_SlaveAllEvents constant is provided as
* a convenient way to enable all events.
*
* param base The I2C peripheral base address.
* param handle Pointer to #i2c_slave_handle_t structure which stores the transfer state.
* param eventMask Bit mask formed by OR'ing together #i2c_slave_transfer_event_t enumerators to specify
* which events to send to the callback. Other accepted values are 0 to get a default set of
* only the transmit and receive events, and #kI2C_SlaveAllEvents to enable all events.
*
* retval #kStatus_Success Slave transfers were successfully started.
* retval #kStatus_I2C_Busy Slave transfers have already been started on this handle.
*/
status_t I2C_SlaveTransferNonBlocking(I2C_Type *base, i2c_slave_handle_t *handle, uint32_t eventMask)
{
assert(handle);
/* Check if the I2C bus is idle - if not return busy status. */
if (handle->isBusy)
{
return kStatus_I2C_Busy;
}
else
{
/* Disable LPI2C IRQ sources while we configure stuff. */
I2C_DisableInterrupts(base, kIrqFlags);
/* 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 | kI2C_SlaveTransmitEvent | kI2C_SlaveReceiveEvent | kI2C_SlaveGenaralcallEvent;
/* Clear all flags. */
I2C_SlaveClearStatusFlags(base, kClearFlags);
/* Enable I2C internal IRQ sources. NVIC IRQ was enabled in CreateHandle() */
I2C_EnableInterrupts(base, kIrqFlags);
}
return kStatus_Success;
}
/*!
* brief Aborts the slave transfer.
*
* note This API can be called at any time to stop slave for handling the bus events.
*
* param base I2C base pointer.
* param handle pointer to i2c_slave_handle_t structure which stores the transfer state.
*/
void I2C_SlaveTransferAbort(I2C_Type *base, i2c_slave_handle_t *handle)
{
assert(handle);
if (handle->isBusy)
{
/* Disable interrupts. */
I2C_DisableInterrupts(base, kIrqFlags);
/* Reset transfer info. */
memset(&handle->transfer, 0, sizeof(handle->transfer));
/* Reset the state to idle. */
handle->isBusy = false;
}
}
/*!
* brief Gets the slave transfer remaining bytes during a interrupt non-blocking transfer.
*
* param base I2C base pointer.
* param handle pointer to i2c_slave_handle_t structure.
* param count Number of bytes transferred so far by the non-blocking transaction.
* retval kStatus_InvalidArgument count is Invalid.
* retval kStatus_Success Successfully return the count.
*/
status_t I2C_SlaveTransferGetCount(I2C_Type *base, i2c_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->transfer.transferredCount;
return kStatus_Success;
}
/*!
* brief Slave interrupt handler.
*
* param base I2C base pointer.
* param i2cHandle pointer to i2c_slave_handle_t structure which stores the transfer state
*/
void I2C_SlaveTransferHandleIRQ(I2C_Type *base, void *i2cHandle)
{
assert(i2cHandle);
uint16_t status;
bool doTransmit = false;
i2c_slave_handle_t *handle = (i2c_slave_handle_t *)i2cHandle;
i2c_slave_transfer_t *xfer;
volatile uint8_t dummy = 0;
/* Add this to avoid build warning. */
dummy++;
status = I2C_SlaveGetStatusFlags(base);
xfer = &(handle->transfer);
#ifdef I2C_HAS_STOP_DETECT
/* Check stop flag. */
if (status & kI2C_StopDetectFlag)
{
I2C_MasterClearStatusFlags(base, kI2C_StopDetectFlag);
/* Clear the interrupt flag. */
base->S = kI2C_IntPendingFlag;
/* Call slave callback if this is the STOP of the transfer. */
if (handle->isBusy)
{
xfer->event = kI2C_SlaveCompletionEvent;
xfer->completionStatus = kStatus_Success;
handle->isBusy = false;
if ((handle->eventMask & xfer->event) && (handle->callback))
{
handle->callback(base, xfer, handle->userData);
}
}
if (!(status & kI2C_AddressMatchFlag))
{
return;
}
}
#endif /* I2C_HAS_STOP_DETECT */
#if defined(FSL_FEATURE_I2C_HAS_START_STOP_DETECT) && FSL_FEATURE_I2C_HAS_START_STOP_DETECT
/* Check start flag. */
if (status & kI2C_StartDetectFlag)
{
I2C_MasterClearStatusFlags(base, kI2C_StartDetectFlag);
/* Clear the interrupt flag. */
base->S = kI2C_IntPendingFlag;
xfer->event = kI2C_SlaveStartEvent;
if ((handle->eventMask & xfer->event) && (handle->callback))
{
handle->callback(base, xfer, handle->userData);
}
if (!(status & kI2C_AddressMatchFlag))
{
return;
}
}
#endif /* FSL_FEATURE_I2C_HAS_START_STOP_DETECT */
/* Clear the interrupt flag. */
base->S = kI2C_IntPendingFlag;
/* Check NAK */
if (status & kI2C_ReceiveNakFlag)
{
/* Set receive mode. */
base->C1 &= ~(I2C_C1_TX_MASK | I2C_C1_TXAK_MASK);
/* Read dummy. */
dummy = base->D;
if (handle->transfer.dataSize != 0)
{
xfer->event = kI2C_SlaveCompletionEvent;
xfer->completionStatus = kStatus_I2C_Nak;
handle->isBusy = false;
if ((handle->eventMask & xfer->event) && (handle->callback))
{
handle->callback(base, xfer, handle->userData);
}
}
else
{
#ifndef I2C_HAS_STOP_DETECT
xfer->event = kI2C_SlaveCompletionEvent;
xfer->completionStatus = kStatus_Success;
handle->isBusy = false;
if ((handle->eventMask & xfer->event) && (handle->callback))
{
handle->callback(base, xfer, handle->userData);
}
#endif /* !FSL_FEATURE_I2C_HAS_START_STOP_DETECT or !FSL_FEATURE_I2C_HAS_STOP_DETECT */
}
}
/* Check address match. */
else if (status & kI2C_AddressMatchFlag)
{
handle->isBusy = true;
xfer->event = kI2C_SlaveAddressMatchEvent;
/* Slave transmit, master reading from slave. */
if (status & kI2C_TransferDirectionFlag)
{
/* Change direction to send data. */
base->C1 |= I2C_C1_TX_MASK;
doTransmit = true;
}
else
{
/* Slave receive, master writing to slave. */
base->C1 &= ~(I2C_C1_TX_MASK | I2C_C1_TXAK_MASK);
/* Read dummy to release the bus. */
dummy = base->D;
if (dummy == 0)
{
xfer->event = kI2C_SlaveGenaralcallEvent;
}
}
if ((handle->eventMask & xfer->event) && (handle->callback))
{
handle->callback(base, xfer, handle->userData);
}
}
/* Check transfer complete flag. */
else if (status & kI2C_TransferCompleteFlag)
{
/* Slave transmit, master reading from slave. */
if (status & kI2C_TransferDirectionFlag)
{
doTransmit = true;
}
else
{
/* If we're out of data, invoke callback to get more. */
if ((!xfer->data) || (!xfer->dataSize))
{
xfer->event = kI2C_SlaveReceiveEvent;
if (handle->callback)
{
handle->callback(base, xfer, handle->userData);
}
/* Clear the transferred count now that we have a new buffer. */
xfer->transferredCount = 0;
}
/* Slave receive, master writing to slave. */
uint8_t data = base->D;
if (handle->transfer.dataSize)
{
/* Receive data. */
*handle->transfer.data++ = data;
handle->transfer.dataSize--;
xfer->transferredCount++;
if (!handle->transfer.dataSize)
{
#ifndef I2C_HAS_STOP_DETECT
xfer->event = kI2C_SlaveCompletionEvent;
xfer->completionStatus = kStatus_Success;
handle->isBusy = false;
/* Proceed receive complete event. */
if ((handle->eventMask & xfer->event) && (handle->callback))
{
handle->callback(base, xfer, handle->userData);
}
#endif /* !FSL_FEATURE_I2C_HAS_START_STOP_DETECT or !FSL_FEATURE_I2C_HAS_STOP_DETECT */
}
}
}
}
else
{
/* Read dummy to release bus. */
dummy = base->D;
}
/* Send data if there is the need. */
if (doTransmit)
{
/* If we're out of data, invoke callback to get more. */
if ((!xfer->data) || (!xfer->dataSize))
{
xfer->event = kI2C_SlaveTransmitEvent;
if (handle->callback)
{
handle->callback(base, xfer, handle->userData);
}
/* Clear the transferred count now that we have a new buffer. */
xfer->transferredCount = 0;
}
if (handle->transfer.dataSize)
{
/* Send data. */
base->D = *handle->transfer.data++;
handle->transfer.dataSize--;
xfer->transferredCount++;
}
else
{
/* Switch to receive mode. */
base->C1 &= ~(I2C_C1_TX_MASK | I2C_C1_TXAK_MASK);
/* Read dummy to release bus. */
dummy = base->D;
#ifndef I2C_HAS_STOP_DETECT
xfer->event = kI2C_SlaveCompletionEvent;
xfer->completionStatus = kStatus_Success;
handle->isBusy = false;
/* Proceed txdone event. */
if ((handle->eventMask & xfer->event) && (handle->callback))
{
handle->callback(base, xfer, handle->userData);
}
#endif /* !FSL_FEATURE_I2C_HAS_START_STOP_DETECT or !FSL_FEATURE_I2C_HAS_STOP_DETECT */
}
}
}
#if defined(I2C0)
void I2C0_DriverIRQHandler(void)
{
I2C_TransferCommonIRQHandler(I2C0, s_i2cHandle[0]);
}
#endif
#if defined(I2C1)
void I2C1_DriverIRQHandler(void)
{
I2C_TransferCommonIRQHandler(I2C1, s_i2cHandle[1]);
}
#endif
#if defined(I2C2)
void I2C2_DriverIRQHandler(void)
{
I2C_TransferCommonIRQHandler(I2C2, s_i2cHandle[2]);
}
#endif
#if defined(I2C3)
void I2C3_DriverIRQHandler(void)
{
I2C_TransferCommonIRQHandler(I2C3, s_i2cHandle[3]);
}
#endif