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rt-thread/bsp/imxrt/libraries/MIMXRT1050/MIMXRT1052/drivers/fsl_lpspi.c

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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_lpspi.h"
/*******************************************************************************
* Definitions
******************************************************************************/
/* Component ID definition, used by tools. */
#ifndef FSL_COMPONENT_ID
#define FSL_COMPONENT_ID "platform.drivers.lpspi"
#endif
/*!
* @brief Default watermark values.
*
* The default watermarks are set to zero.
*/
enum _lpspi_default_watermarks
{
kLpspiDefaultTxWatermark = 0,
kLpspiDefaultRxWatermark = 0,
};
/*! @brief Typedef for master interrupt handler. */
typedef void (*lpspi_master_isr_t)(LPSPI_Type *base, lpspi_master_handle_t *handle);
/*! @brief Typedef for slave interrupt handler. */
typedef void (*lpspi_slave_isr_t)(LPSPI_Type *base, lpspi_slave_handle_t *handle);
/*******************************************************************************
* Prototypes
******************************************************************************/
/*!
* @brief Get instance number for LPSPI module.
*
* @param base LPSPI peripheral base address.
* @return Return the value of LPSPI instance.
*/
uint32_t LPSPI_GetInstance(LPSPI_Type *base);
/*!
* @brief Configures the LPSPI peripheral chip select polarity.
*
* This function takes in the desired peripheral chip select (Pcs) and it's corresponding desired polarity and
* configures the Pcs signal to operate with the desired characteristic.
*
* @param base LPSPI peripheral address.
* @param pcs The particular peripheral chip select (parameter value is of type lpspi_which_pcs_t) for which we wish to
* apply the active high or active low characteristic.
* @param activeLowOrHigh The setting for either "active high, inactive low (0)" or "active low, inactive high(1)" of
* type lpspi_pcs_polarity_config_t.
*/
static void LPSPI_SetOnePcsPolarity(LPSPI_Type *base,
lpspi_which_pcs_t pcs,
lpspi_pcs_polarity_config_t activeLowOrHigh);
/*!
* @brief Combine the write data for 1 byte to 4 bytes.
* This is not a public API.
*/
static uint32_t LPSPI_CombineWriteData(uint8_t *txData, uint32_t bytesEachWrite, bool isByteSwap);
/*!
* @brief Separate the read data for 1 byte to 4 bytes.
* This is not a public API.
*/
static void LPSPI_SeparateReadData(uint8_t *rxData, uint32_t readData, uint32_t bytesEachRead, bool isByteSwap);
/*!
* @brief Master fill up the TX FIFO with data.
* This is not a public API.
*/
static void LPSPI_MasterTransferFillUpTxFifo(LPSPI_Type *base, lpspi_master_handle_t *handle);
/*!
* @brief Master finish up a transfer.
* It would call back if there is callback function and set the state to idle.
* This is not a public API.
*/
static void LPSPI_MasterTransferComplete(LPSPI_Type *base, lpspi_master_handle_t *handle);
/*!
* @brief Slave fill up the TX FIFO with data.
* This is not a public API.
*/
static void LPSPI_SlaveTransferFillUpTxFifo(LPSPI_Type *base, lpspi_slave_handle_t *handle);
/*!
* @brief Slave finish up a transfer.
* It would call back if there is callback function and set the state to idle.
* This is not a public API.
*/
static void LPSPI_SlaveTransferComplete(LPSPI_Type *base, lpspi_slave_handle_t *handle);
/*!
* @brief LPSPI common interrupt handler.
*
* @param handle pointer to s_lpspiHandle which stores the transfer state.
*/
static void LPSPI_CommonIRQHandler(LPSPI_Type *base, void *param);
/*******************************************************************************
* Variables
******************************************************************************/
/* Defines constant value arrays for the baud rate pre-scalar and scalar divider values.*/
static const uint8_t s_baudratePrescaler[] = {1, 2, 4, 8, 16, 32, 64, 128};
/*! @brief Pointers to lpspi bases for each instance. */
static LPSPI_Type *const s_lpspiBases[] = LPSPI_BASE_PTRS;
/*! @brief Pointers to lpspi IRQ number for each instance. */
static const IRQn_Type s_lpspiIRQ[] = LPSPI_IRQS;
#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
/*! @brief Pointers to lpspi clocks for each instance. */
static const clock_ip_name_t s_lpspiClocks[] = LPSPI_CLOCKS;
#if defined(LPSPI_PERIPH_CLOCKS)
static const clock_ip_name_t s_LpspiPeriphClocks[] = LPSPI_PERIPH_CLOCKS;
#endif
#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */
/*! @brief Pointers to lpspi handles for each instance. */
static void *s_lpspiHandle[ARRAY_SIZE(s_lpspiBases)] = {NULL};
/*! @brief Pointer to master IRQ handler for each instance. */
static lpspi_master_isr_t s_lpspiMasterIsr;
/*! @brief Pointer to slave IRQ handler for each instance. */
static lpspi_slave_isr_t s_lpspiSlaveIsr;
/* @brief Dummy data for each instance. This data is used when user's tx buffer is NULL*/
volatile uint8_t g_lpspiDummyData[ARRAY_SIZE(s_lpspiBases)] = {0};
/**********************************************************************************************************************
* Code
*********************************************************************************************************************/
uint32_t LPSPI_GetInstance(LPSPI_Type *base)
{
uint8_t instance = 0;
/* Find the instance index from base address mappings. */
for (instance = 0; instance < ARRAY_SIZE(s_lpspiBases); instance++)
{
if (s_lpspiBases[instance] == base)
{
break;
}
}
assert(instance < ARRAY_SIZE(s_lpspiBases));
return instance;
}
/*!
* brief Set up the dummy data.
*
* param base LPSPI peripheral address.
* param dummyData Data to be transferred when tx buffer is NULL.
* Note:
* This API has no effect when LPSPI in slave interrupt mode, because driver
* will set the TXMSK bit to 1 if txData is NULL, no data is loaded from transmit
* FIFO and output pin is tristated.
*/
void LPSPI_SetDummyData(LPSPI_Type *base, uint8_t dummyData)
{
uint32_t instance = LPSPI_GetInstance(base);
g_lpspiDummyData[instance] = dummyData;
}
/*!
* brief Initializes the LPSPI master.
*
* param base LPSPI peripheral address.
* param masterConfig Pointer to structure lpspi_master_config_t.
* param srcClock_Hz Module source input clock in Hertz
*/
void LPSPI_MasterInit(LPSPI_Type *base, const lpspi_master_config_t *masterConfig, uint32_t srcClock_Hz)
{
assert(masterConfig);
uint32_t tcrPrescaleValue = 0;
#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
uint32_t instance = LPSPI_GetInstance(base);
/* Enable LPSPI clock */
CLOCK_EnableClock(s_lpspiClocks[instance]);
#if defined(LPSPI_PERIPH_CLOCKS)
CLOCK_EnableClock(s_LpspiPeriphClocks[instance]);
#endif
#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */
/* Set LPSPI to master */
LPSPI_SetMasterSlaveMode(base, kLPSPI_Master);
/* Set specific PCS to active high or low */
LPSPI_SetOnePcsPolarity(base, masterConfig->whichPcs, masterConfig->pcsActiveHighOrLow);
/* Set Configuration Register 1 related setting.*/
base->CFGR1 = (base->CFGR1 & ~(LPSPI_CFGR1_OUTCFG_MASK | LPSPI_CFGR1_PINCFG_MASK | LPSPI_CFGR1_NOSTALL_MASK)) |
LPSPI_CFGR1_OUTCFG(masterConfig->dataOutConfig) | LPSPI_CFGR1_PINCFG(masterConfig->pinCfg) |
LPSPI_CFGR1_NOSTALL(0);
/* Set baudrate and delay times*/
LPSPI_MasterSetBaudRate(base, masterConfig->baudRate, srcClock_Hz, &tcrPrescaleValue);
/* Set default watermarks */
LPSPI_SetFifoWatermarks(base, kLpspiDefaultTxWatermark, kLpspiDefaultRxWatermark);
/* Set Transmit Command Register*/
base->TCR = LPSPI_TCR_CPOL(masterConfig->cpol) | LPSPI_TCR_CPHA(masterConfig->cpha) |
LPSPI_TCR_LSBF(masterConfig->direction) | LPSPI_TCR_FRAMESZ(masterConfig->bitsPerFrame - 1) |
LPSPI_TCR_PRESCALE(tcrPrescaleValue) | LPSPI_TCR_PCS(masterConfig->whichPcs);
LPSPI_Enable(base, true);
LPSPI_MasterSetDelayTimes(base, masterConfig->pcsToSckDelayInNanoSec, kLPSPI_PcsToSck, srcClock_Hz);
LPSPI_MasterSetDelayTimes(base, masterConfig->lastSckToPcsDelayInNanoSec, kLPSPI_LastSckToPcs, srcClock_Hz);
LPSPI_MasterSetDelayTimes(base, masterConfig->betweenTransferDelayInNanoSec, kLPSPI_BetweenTransfer, srcClock_Hz);
LPSPI_SetDummyData(base, LPSPI_DUMMY_DATA);
}
/*!
* brief Sets the lpspi_master_config_t structure to default values.
*
* This API initializes the configuration structure for LPSPI_MasterInit().
* The initialized structure can remain unchanged in LPSPI_MasterInit(), or can be modified
* before calling the LPSPI_MasterInit().
* Example:
* code
* lpspi_master_config_t masterConfig;
* LPSPI_MasterGetDefaultConfig(&masterConfig);
* endcode
* param masterConfig pointer to lpspi_master_config_t structure
*/
void LPSPI_MasterGetDefaultConfig(lpspi_master_config_t *masterConfig)
{
assert(masterConfig);
/* Initializes the configure structure to zero. */
memset(masterConfig, 0, sizeof(*masterConfig));
masterConfig->baudRate = 500000;
masterConfig->bitsPerFrame = 8;
masterConfig->cpol = kLPSPI_ClockPolarityActiveHigh;
masterConfig->cpha = kLPSPI_ClockPhaseFirstEdge;
masterConfig->direction = kLPSPI_MsbFirst;
masterConfig->pcsToSckDelayInNanoSec = 1000000000 / masterConfig->baudRate * 2;
masterConfig->lastSckToPcsDelayInNanoSec = 1000000000 / masterConfig->baudRate * 2;
masterConfig->betweenTransferDelayInNanoSec = 1000000000 / masterConfig->baudRate * 2;
masterConfig->whichPcs = kLPSPI_Pcs0;
masterConfig->pcsActiveHighOrLow = kLPSPI_PcsActiveLow;
masterConfig->pinCfg = kLPSPI_SdiInSdoOut;
masterConfig->dataOutConfig = kLpspiDataOutRetained;
}
/*!
* brief LPSPI slave configuration.
*
* param base LPSPI peripheral address.
* param slaveConfig Pointer to a structure lpspi_slave_config_t.
*/
void LPSPI_SlaveInit(LPSPI_Type *base, const lpspi_slave_config_t *slaveConfig)
{
assert(slaveConfig);
#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
uint32_t instance = LPSPI_GetInstance(base);
/* Enable LPSPI clock */
CLOCK_EnableClock(s_lpspiClocks[instance]);
#if defined(LPSPI_PERIPH_CLOCKS)
CLOCK_EnableClock(s_LpspiPeriphClocks[instance]);
#endif
#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */
LPSPI_SetMasterSlaveMode(base, kLPSPI_Slave);
LPSPI_SetOnePcsPolarity(base, slaveConfig->whichPcs, slaveConfig->pcsActiveHighOrLow);
base->CFGR1 = (base->CFGR1 & ~(LPSPI_CFGR1_OUTCFG_MASK | LPSPI_CFGR1_PINCFG_MASK)) |
LPSPI_CFGR1_OUTCFG(slaveConfig->dataOutConfig) | LPSPI_CFGR1_PINCFG(slaveConfig->pinCfg);
LPSPI_SetFifoWatermarks(base, kLpspiDefaultTxWatermark, kLpspiDefaultRxWatermark);
base->TCR = LPSPI_TCR_CPOL(slaveConfig->cpol) | LPSPI_TCR_CPHA(slaveConfig->cpha) |
LPSPI_TCR_LSBF(slaveConfig->direction) | LPSPI_TCR_FRAMESZ(slaveConfig->bitsPerFrame - 1);
/* This operation will set the dummy data for edma transfer, no effect in interrupt way. */
LPSPI_SetDummyData(base, LPSPI_DUMMY_DATA);
LPSPI_Enable(base, true);
}
/*!
* brief Sets the lpspi_slave_config_t structure to default values.
*
* This API initializes the configuration structure for LPSPI_SlaveInit().
* The initialized structure can remain unchanged in LPSPI_SlaveInit() or can be modified
* before calling the LPSPI_SlaveInit().
* Example:
* code
* lpspi_slave_config_t slaveConfig;
* LPSPI_SlaveGetDefaultConfig(&slaveConfig);
* endcode
* param slaveConfig pointer to lpspi_slave_config_t structure.
*/
void LPSPI_SlaveGetDefaultConfig(lpspi_slave_config_t *slaveConfig)
{
assert(slaveConfig);
/* Initializes the configure structure to zero. */
memset(slaveConfig, 0, sizeof(*slaveConfig));
slaveConfig->bitsPerFrame = 8; /*!< Bits per frame, minimum 8, maximum 4096.*/
slaveConfig->cpol = kLPSPI_ClockPolarityActiveHigh; /*!< Clock polarity. */
slaveConfig->cpha = kLPSPI_ClockPhaseFirstEdge; /*!< Clock phase. */
slaveConfig->direction = kLPSPI_MsbFirst; /*!< MSB or LSB data shift direction. */
slaveConfig->whichPcs = kLPSPI_Pcs0; /*!< Desired Peripheral Chip Select (pcs) */
slaveConfig->pcsActiveHighOrLow = kLPSPI_PcsActiveLow; /*!< Desired PCS active high or low */
slaveConfig->pinCfg = kLPSPI_SdiInSdoOut;
slaveConfig->dataOutConfig = kLpspiDataOutRetained;
}
/*!
* brief Restores the LPSPI peripheral to reset state. Note that this function
* sets all registers to reset state. As a result, the LPSPI module can't work after calling
* this API.
* param base LPSPI peripheral address.
*/
void LPSPI_Reset(LPSPI_Type *base)
{
/* Reset all internal logic and registers, except the Control Register. Remains set until cleared by software.*/
base->CR |= LPSPI_CR_RST_MASK;
/* Software reset doesn't reset the CR, so manual reset the FIFOs */
base->CR |= LPSPI_CR_RRF_MASK | LPSPI_CR_RTF_MASK;
/* Master logic is not reset and module is disabled.*/
base->CR = 0x00U;
}
/*!
* brief De-initializes the LPSPI peripheral. Call this API to disable the LPSPI clock.
* param base LPSPI peripheral address.
*/
void LPSPI_Deinit(LPSPI_Type *base)
{
/* Reset to default value */
LPSPI_Reset(base);
#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
uint32_t instance = LPSPI_GetInstance(base);
/* Enable LPSPI clock */
CLOCK_DisableClock(s_lpspiClocks[instance]);
#if defined(LPSPI_PERIPH_CLOCKS)
CLOCK_DisableClock(s_LpspiPeriphClocks[instance]);
#endif
#endif /* FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL */
}
static void LPSPI_SetOnePcsPolarity(LPSPI_Type *base,
lpspi_which_pcs_t pcs,
lpspi_pcs_polarity_config_t activeLowOrHigh)
{
uint32_t cfgr1Value = 0;
/* Clear the PCS polarity bit */
cfgr1Value = base->CFGR1 & ~(1U << (LPSPI_CFGR1_PCSPOL_SHIFT + pcs));
/* Configure the PCS polarity bit according to the activeLowOrHigh setting */
base->CFGR1 = cfgr1Value | ((uint32_t)activeLowOrHigh << (LPSPI_CFGR1_PCSPOL_SHIFT + pcs));
}
/*!
* brief Sets the LPSPI baud rate in bits per second.
*
* This function takes in the desired bitsPerSec (baud rate) and calculates the nearest
* possible baud rate without exceeding the desired baud rate and returns the
* calculated baud rate in bits-per-second. It requires the caller to provide
* the frequency of the module source clock (in Hertz). Note that the baud rate
* does not go into effect until the Transmit Control Register (TCR) is programmed
* with the prescale value. Hence, this function returns the prescale tcrPrescaleValue
* parameter for later programming in the TCR. The higher level
* peripheral driver should alert the user of an out of range baud rate input.
*
* Note that the LPSPI module must first be disabled before configuring this.
* Note that the LPSPI module must be configured for master mode before configuring this.
*
* param base LPSPI peripheral address.
* param baudRate_Bps The desired baud rate in bits per second.
* param srcClock_Hz Module source input clock in Hertz.
* param tcrPrescaleValue The TCR prescale value needed to program the TCR.
* return The actual calculated baud rate. This function may also return a "0" if the
* LPSPI is not configured for master mode or if the LPSPI module is not disabled.
*/
uint32_t LPSPI_MasterSetBaudRate(LPSPI_Type *base,
uint32_t baudRate_Bps,
uint32_t srcClock_Hz,
uint32_t *tcrPrescaleValue)
{
assert(tcrPrescaleValue);
/* For master mode configuration only, if slave mode detected, return 0.
* Also, the LPSPI module needs to be disabled first, if enabled, return 0
*/
if ((!LPSPI_IsMaster(base)) || (base->CR & LPSPI_CR_MEN_MASK))
{
return 0;
}
uint32_t prescaler, bestPrescaler;
uint32_t scaler, bestScaler;
uint32_t realBaudrate, bestBaudrate;
uint32_t diff, min_diff;
uint32_t desiredBaudrate = baudRate_Bps;
/* find combination of prescaler and scaler resulting in baudrate closest to the
* requested value
*/
min_diff = 0xFFFFFFFFU;
/* Set to maximum divisor value bit settings so that if baud rate passed in is less
* than the minimum possible baud rate, then the SPI will be configured to the lowest
* possible baud rate
*/
bestPrescaler = 7;
bestScaler = 255;
bestBaudrate = 0; /* required to avoid compilation warning */
/* In all for loops, if min_diff = 0, the exit for loop*/
for (prescaler = 0; (prescaler < 8) && min_diff; prescaler++)
{
for (scaler = 0; (scaler < 256) && min_diff; scaler++)
{
realBaudrate = (srcClock_Hz / (s_baudratePrescaler[prescaler] * (scaler + 2U)));
/* calculate the baud rate difference based on the conditional statement
* that states that the calculated baud rate must not exceed the desired baud rate
*/
if (desiredBaudrate >= realBaudrate)
{
diff = desiredBaudrate - realBaudrate;
if (min_diff > diff)
{
/* a better match found */
min_diff = diff;
bestPrescaler = prescaler;
bestScaler = scaler;
bestBaudrate = realBaudrate;
}
}
}
}
/* Write the best baud rate scalar to the CCR.
* Note, no need to check for error since we've already checked to make sure the module is
* disabled and in master mode. Also, there is a limit on the maximum divider so we will not
* exceed this.
*/
base->CCR = (base->CCR & ~LPSPI_CCR_SCKDIV_MASK) | LPSPI_CCR_SCKDIV(bestScaler);
/* return the best prescaler value for user to use later */
*tcrPrescaleValue = bestPrescaler;
/* return the actual calculated baud rate */
return bestBaudrate;
}
/*!
* brief Manually configures a specific LPSPI delay parameter (module must be disabled to
* change the delay values).
*
* This function configures the following:
* SCK to PCS delay, or
* PCS to SCK delay, or
* The configurations must occur between the transfer delay.
*
* The delay names are available in type lpspi_delay_type_t.
*
* The user passes the desired delay along with the delay value.
* This allows the user to directly set the delay values if they have
* pre-calculated them or if they simply wish to manually increment the value.
*
* Note that the LPSPI module must first be disabled before configuring this.
* Note that the LPSPI module must be configured for master mode before configuring this.
*
* param base LPSPI peripheral address.
* param scaler The 8-bit delay value 0x00 to 0xFF (255).
* param whichDelay The desired delay to configure, must be of type lpspi_delay_type_t.
*/
void LPSPI_MasterSetDelayScaler(LPSPI_Type *base, uint32_t scaler, lpspi_delay_type_t whichDelay)
{
/*These settings are only relevant in master mode */
switch (whichDelay)
{
case kLPSPI_PcsToSck:
base->CCR = (base->CCR & (~LPSPI_CCR_PCSSCK_MASK)) | LPSPI_CCR_PCSSCK(scaler);
break;
case kLPSPI_LastSckToPcs:
base->CCR = (base->CCR & (~LPSPI_CCR_SCKPCS_MASK)) | LPSPI_CCR_SCKPCS(scaler);
break;
case kLPSPI_BetweenTransfer:
base->CCR = (base->CCR & (~LPSPI_CCR_DBT_MASK)) | LPSPI_CCR_DBT(scaler);
break;
default:
assert(false);
break;
}
}
/*!
* brief Calculates the delay based on the desired delay input in nanoseconds (module must be
* disabled to change the delay values).
*
* This function calculates the values for the following:
* SCK to PCS delay, or
* PCS to SCK delay, or
* The configurations must occur between the transfer delay.
*
* The delay names are available in type lpspi_delay_type_t.
*
* The user passes the desired delay and the desired delay value in
* nano-seconds. The function calculates the value needed for the desired delay parameter
* and returns the actual calculated delay because an exact delay match may not be possible. In this
* case, the closest match is calculated without going below the desired delay value input.
* It is possible to input a very large delay value that exceeds the capability of the part, in
* which case the maximum supported delay is returned. It is up to the higher level
* peripheral driver to alert the user of an out of range delay input.
*
* Note that the LPSPI module must be configured for master mode before configuring this. And note that
* the delayTime = LPSPI_clockSource / (PRESCALE * Delay_scaler).
*
* param base LPSPI peripheral address.
* param delayTimeInNanoSec The desired delay value in nano-seconds.
* param whichDelay The desired delay to configuration, which must be of type lpspi_delay_type_t.
* param srcClock_Hz Module source input clock in Hertz.
* return actual Calculated delay value in nano-seconds.
*/
uint32_t LPSPI_MasterSetDelayTimes(LPSPI_Type *base,
uint32_t delayTimeInNanoSec,
lpspi_delay_type_t whichDelay,
uint32_t srcClock_Hz)
{
uint64_t realDelay, bestDelay;
uint32_t scaler, bestScaler;
uint32_t diff, min_diff;
uint64_t initialDelayNanoSec;
uint32_t clockDividedPrescaler;
/* For delay between transfer, an additional scaler value is needed */
uint32_t additionalScaler = 0;
/*As the RM note, the LPSPI baud rate clock is itself divided by the PRESCALE setting, which can vary between
* transfers.*/
clockDividedPrescaler =
srcClock_Hz / s_baudratePrescaler[(base->TCR & LPSPI_TCR_PRESCALE_MASK) >> LPSPI_TCR_PRESCALE_SHIFT];
/* Find combination of prescaler and scaler resulting in the delay closest to the requested value.*/
min_diff = 0xFFFFFFFFU;
/* Initialize scaler to max value to generate the max delay */
bestScaler = 0xFFU;
/* Calculate the initial (min) delay and maximum possible delay based on the specific delay as
* the delay divisors are slightly different based on which delay we are configuring.
*/
if (whichDelay == kLPSPI_BetweenTransfer)
{
/* First calculate the initial, default delay, note min delay is 2 clock cycles. Due to large size of
calculated values (uint64_t), we need to break up the calculation into several steps to ensure
accurate calculated results
*/
initialDelayNanoSec = 1000000000U;
initialDelayNanoSec *= 2U;
initialDelayNanoSec /= clockDividedPrescaler;
/* Calculate the maximum delay */
bestDelay = 1000000000U;
bestDelay *= 257U; /* based on DBT+2, or 255 + 2 */
bestDelay /= clockDividedPrescaler;
additionalScaler = 1U;
}
else
{
/* First calculate the initial, default delay, min delay is 1 clock cycle. Due to large size of calculated
values (uint64_t), we need to break up the calculation into several steps to ensure accurate calculated
results.
*/
initialDelayNanoSec = 1000000000U;
initialDelayNanoSec /= clockDividedPrescaler;
/* Calculate the maximum delay */
bestDelay = 1000000000U;
bestDelay *= 256U; /* based on SCKPCS+1 or PCSSCK+1, or 255 + 1 */
bestDelay /= clockDividedPrescaler;
additionalScaler = 0;
}
/* If the initial, default delay is already greater than the desired delay, then
* set the delay to their initial value (0) and return the delay. In other words,
* there is no way to decrease the delay value further.
*/
if (initialDelayNanoSec >= delayTimeInNanoSec)
{
LPSPI_MasterSetDelayScaler(base, 0, whichDelay);
return initialDelayNanoSec;
}
/* If min_diff = 0, the exit for loop */
for (scaler = 0; (scaler < 256U) && min_diff; scaler++)
{
/* Calculate the real delay value as we cycle through the scaler values.
Due to large size of calculated values (uint64_t), we need to break up the
calculation into several steps to ensure accurate calculated results
*/
realDelay = 1000000000U;
realDelay *= (scaler + 1 + additionalScaler);
realDelay /= clockDividedPrescaler;
/* calculate the delay difference based on the conditional statement
* that states that the calculated delay must not be less then the desired delay
*/
if (realDelay >= delayTimeInNanoSec)
{
diff = realDelay - delayTimeInNanoSec;
if (min_diff > diff)
{
/* a better match found */
min_diff = diff;
bestScaler = scaler;
bestDelay = realDelay;
}
}
}
/* write the best scaler value for the delay */
LPSPI_MasterSetDelayScaler(base, bestScaler, whichDelay);
/* return the actual calculated delay value (in ns) */
return bestDelay;
}
/*Transactional APIs -- Master*/
/*!
* brief Initializes the LPSPI master handle.
*
* This function initializes the LPSPI handle, which can be used for other LPSPI transactional APIs. Usually, for a
* specified LPSPI instance, call this API once to get the initialized handle.
* param base LPSPI peripheral address.
* param handle LPSPI handle pointer to lpspi_master_handle_t.
* param callback DSPI callback.
* param userData callback function parameter.
*/
void LPSPI_MasterTransferCreateHandle(LPSPI_Type *base,
lpspi_master_handle_t *handle,
lpspi_master_transfer_callback_t callback,
void *userData)
{
assert(handle);
/* Zero the handle. */
memset(handle, 0, sizeof(*handle));
s_lpspiHandle[LPSPI_GetInstance(base)] = handle;
/* Set irq handler. */
s_lpspiMasterIsr = LPSPI_MasterTransferHandleIRQ;
handle->callback = callback;
handle->userData = userData;
}
/*!
* brief Check the argument for transfer .
*
* param transfer the transfer struct to be used.
* param bitPerFrame The bit size of one frame.
* param bytePerFrame The byte size of one frame.
* return Return true for right and false for wrong.
*/
bool LPSPI_CheckTransferArgument(lpspi_transfer_t *transfer, uint32_t bitsPerFrame, uint32_t bytesPerFrame)
{
assert(transfer);
/* If the transfer count is zero, then return immediately.*/
if (transfer->dataSize == 0)
{
return false;
}
/* If both send buffer and receive buffer is null */
if ((!(transfer->txData)) && (!(transfer->rxData)))
{
return false;
}
/*The transfer data size should be integer multiples of bytesPerFrame if bytesPerFrame is less than or equal to 4 .
*For bytesPerFrame greater than 4 situation:
*the transfer data size should be equal to bytesPerFrame if the bytesPerFrame is not integer multiples of 4 ,
*otherwise , the transfer data size can be integer multiples of bytesPerFrame.
*/
if (bytesPerFrame <= 4)
{
if ((transfer->dataSize % bytesPerFrame) != 0)
{
return false;
}
}
else
{
if ((bytesPerFrame % 4U) != 0)
{
if (transfer->dataSize != bytesPerFrame)
{
return false;
}
}
else
{
if ((transfer->dataSize % bytesPerFrame) != 0)
{
return false;
}
}
}
return true;
}
/*!
* brief LPSPI master transfer data using a polling method.
*
* This function transfers data using a polling method. This is a blocking function, which does not return until all
* transfers have been
* completed.
*
* Note:
* The transfer data size should be integer multiples of bytesPerFrame if bytesPerFrame is less than or equal to 4.
* For bytesPerFrame greater than 4:
* The transfer data size should be equal to bytesPerFrame if the bytesPerFrame is not integer multiples of 4.
* Otherwise, the transfer data size can be an integer multiple of bytesPerFrame.
*
* param base LPSPI peripheral address.
* param transfer pointer to lpspi_transfer_t structure.
* return status of status_t.
*/
status_t LPSPI_MasterTransferBlocking(LPSPI_Type *base, lpspi_transfer_t *transfer)
{
assert(transfer);
uint32_t bitsPerFrame = ((base->TCR & LPSPI_TCR_FRAMESZ_MASK) >> LPSPI_TCR_FRAMESZ_SHIFT) + 1;
uint32_t bytesPerFrame = (bitsPerFrame + 7) / 8;
uint32_t temp = 0U;
uint8_t dummyData = g_lpspiDummyData[LPSPI_GetInstance(base)];
if (!LPSPI_CheckTransferArgument(transfer, bitsPerFrame, bytesPerFrame))
{
return kStatus_InvalidArgument;
}
/* Check that LPSPI is not busy.*/
if (LPSPI_GetStatusFlags(base) & kLPSPI_ModuleBusyFlag)
{
return kStatus_LPSPI_Busy;
}
uint8_t *txData = transfer->txData;
uint8_t *rxData = transfer->rxData;
uint32_t txRemainingByteCount = transfer->dataSize;
uint32_t rxRemainingByteCount = transfer->dataSize;
uint8_t bytesEachWrite;
uint8_t bytesEachRead;
uint32_t readData = 0;
uint32_t wordToSend =
((uint32_t)dummyData) | ((uint32_t)dummyData << 8) | ((uint32_t)dummyData << 16) | ((uint32_t)dummyData << 24);
/*The TX and RX FIFO sizes are always the same*/
uint32_t fifoSize = LPSPI_GetRxFifoSize(base);
uint32_t whichPcs = (transfer->configFlags & LPSPI_MASTER_PCS_MASK) >> LPSPI_MASTER_PCS_SHIFT;
bool isPcsContinuous = (bool)(transfer->configFlags & kLPSPI_MasterPcsContinuous);
bool isRxMask = false;
bool isByteSwap = (bool)(transfer->configFlags & kLPSPI_MasterByteSwap);
LPSPI_FlushFifo(base, true, true);
LPSPI_ClearStatusFlags(base, kLPSPI_AllStatusFlag);
if (!rxData)
{
isRxMask = true;
}
LPSPI_Enable(base, false);
base->CFGR1 &= (~LPSPI_CFGR1_NOSTALL_MASK);
/* Check if using 3-wire mode and the txData is NULL, set the output pin to tristated. */
temp = base->CFGR1;
temp &= LPSPI_CFGR1_PINCFG_MASK;
if ((temp == LPSPI_CFGR1_PINCFG(kLPSPI_SdiInSdiOut)) || (temp == LPSPI_CFGR1_PINCFG(kLPSPI_SdoInSdoOut)))
{
if (!txData)
{
base->CFGR1 |= LPSPI_CFGR1_OUTCFG_MASK;
}
/* The 3-wire mode can't send and receive data at the same time. */
if ((txData) && (rxData))
{
return kStatus_InvalidArgument;
}
}
LPSPI_Enable(base, true);
base->TCR =
(base->TCR & ~(LPSPI_TCR_CONT_MASK | LPSPI_TCR_CONTC_MASK | LPSPI_TCR_RXMSK_MASK | LPSPI_TCR_PCS_MASK)) |
LPSPI_TCR_CONT(isPcsContinuous) | LPSPI_TCR_CONTC(0) | LPSPI_TCR_RXMSK(isRxMask) | LPSPI_TCR_PCS(whichPcs);
if (bytesPerFrame <= 4)
{
bytesEachWrite = bytesPerFrame;
bytesEachRead = bytesPerFrame;
}
else
{
bytesEachWrite = 4;
bytesEachRead = 4;
}
/*Write the TX data until txRemainingByteCount is equal to 0 */
while (txRemainingByteCount > 0)
{
if (txRemainingByteCount < bytesEachWrite)
{
bytesEachWrite = txRemainingByteCount;
}
/*Wait until TX FIFO is not full*/
while (LPSPI_GetTxFifoCount(base) == fifoSize)
{
}
if (txData)
{
wordToSend = LPSPI_CombineWriteData(txData, bytesEachWrite, isByteSwap);
txData += bytesEachWrite;
}
LPSPI_WriteData(base, wordToSend);
txRemainingByteCount -= bytesEachWrite;
/*Check whether there is RX data in RX FIFO . Read out the RX data so that the RX FIFO would not overrun.*/
if (rxData)
{
while (LPSPI_GetRxFifoCount(base))
{
readData = LPSPI_ReadData(base);
if (rxRemainingByteCount < bytesEachRead)
{
bytesEachRead = rxRemainingByteCount;
}
LPSPI_SeparateReadData(rxData, readData, bytesEachRead, isByteSwap);
rxData += bytesEachRead;
rxRemainingByteCount -= bytesEachRead;
}
}
}
/* After write all the data in TX FIFO , should write the TCR_CONTC to 0 to de-assert the PCS. Note that TCR
* register also use the TX FIFO.
*/
while ((LPSPI_GetTxFifoCount(base) == fifoSize))
{
}
base->TCR = (base->TCR & ~(LPSPI_TCR_CONTC_MASK));
/*Read out the RX data in FIFO*/
if (rxData)
{
while (rxRemainingByteCount > 0)
{
while (LPSPI_GetRxFifoCount(base))
{
readData = LPSPI_ReadData(base);
if (rxRemainingByteCount < bytesEachRead)
{
bytesEachRead = rxRemainingByteCount;
}
LPSPI_SeparateReadData(rxData, readData, bytesEachRead, isByteSwap);
rxData += bytesEachRead;
rxRemainingByteCount -= bytesEachRead;
}
}
}
else
{
/* If no RX buffer, then transfer is not complete until transfer complete flag sets */
while (!(LPSPI_GetStatusFlags(base) & kLPSPI_TransferCompleteFlag))
{
}
}
return kStatus_Success;
}
/*!
* brief LPSPI master transfer data using an interrupt method.
*
* This function transfers data using an interrupt method. This is a non-blocking function, which returns right away.
* When all data
* is transferred, the callback function is called.
*
* Note:
* The transfer data size should be integer multiples of bytesPerFrame if bytesPerFrame is less than or equal to 4.
* For bytesPerFrame greater than 4:
* The transfer data size should be equal to bytesPerFrame if the bytesPerFrame is not integer multiples of 4.
* Otherwise, the transfer data size can be an integer multiple of bytesPerFrame.
*
* param base LPSPI peripheral address.
* param handle pointer to lpspi_master_handle_t structure which stores the transfer state.
* param transfer pointer to lpspi_transfer_t structure.
* return status of status_t.
*/
status_t LPSPI_MasterTransferNonBlocking(LPSPI_Type *base, lpspi_master_handle_t *handle, lpspi_transfer_t *transfer)
{
assert(handle);
assert(transfer);
uint32_t bitsPerFrame = ((base->TCR & LPSPI_TCR_FRAMESZ_MASK) >> LPSPI_TCR_FRAMESZ_SHIFT) + 1;
uint32_t bytesPerFrame = (bitsPerFrame + 7) / 8;
uint32_t temp = 0U;
uint8_t dummyData = g_lpspiDummyData[LPSPI_GetInstance(base)];
if (!LPSPI_CheckTransferArgument(transfer, bitsPerFrame, bytesPerFrame))
{
return kStatus_InvalidArgument;
}
/* Check that we're not busy.*/
if (handle->state == kLPSPI_Busy)
{
return kStatus_LPSPI_Busy;
}
handle->state = kLPSPI_Busy;
bool isRxMask = false;
uint8_t txWatermark;
uint32_t whichPcs = (transfer->configFlags & LPSPI_MASTER_PCS_MASK) >> LPSPI_MASTER_PCS_SHIFT;
handle->txData = transfer->txData;
handle->rxData = transfer->rxData;
handle->txRemainingByteCount = transfer->dataSize;
handle->rxRemainingByteCount = transfer->dataSize;
handle->totalByteCount = transfer->dataSize;
handle->writeTcrInIsr = false;
handle->writeRegRemainingTimes = (transfer->dataSize / bytesPerFrame) * ((bytesPerFrame + 3) / 4);
handle->readRegRemainingTimes = handle->writeRegRemainingTimes;
handle->txBuffIfNull =
((uint32_t)dummyData) | ((uint32_t)dummyData << 8) | ((uint32_t)dummyData << 16) | ((uint32_t)dummyData << 24);
/*The TX and RX FIFO sizes are always the same*/
handle->fifoSize = LPSPI_GetRxFifoSize(base);
handle->isPcsContinuous = (bool)(transfer->configFlags & kLPSPI_MasterPcsContinuous);
handle->isByteSwap = (bool)(transfer->configFlags & kLPSPI_MasterByteSwap);
/*Set the RX and TX watermarks to reduce the ISR times.*/
if (handle->fifoSize > 1)
{
txWatermark = 1;
handle->rxWatermark = handle->fifoSize - 2;
}
else
{
txWatermark = 0;
handle->rxWatermark = 0;
}
LPSPI_SetFifoWatermarks(base, txWatermark, handle->rxWatermark);
LPSPI_Enable(base, false);
/*Transfers will stall when transmit FIFO is empty or receive FIFO is full. */
base->CFGR1 &= (~LPSPI_CFGR1_NOSTALL_MASK);
/* Check if using 3-wire mode and the txData is NULL, set the output pin to tristated. */
temp = base->CFGR1;
temp &= LPSPI_CFGR1_PINCFG_MASK;
if ((temp == LPSPI_CFGR1_PINCFG(kLPSPI_SdiInSdiOut)) || (temp == LPSPI_CFGR1_PINCFG(kLPSPI_SdoInSdoOut)))
{
if (!handle->txData)
{
base->CFGR1 |= LPSPI_CFGR1_OUTCFG_MASK;
}
/* The 3-wire mode can't send and receive data at the same time. */
if ((handle->txData) && (handle->rxData))
{
return kStatus_InvalidArgument;
}
}
LPSPI_Enable(base, true);
/*Flush FIFO , clear status , disable all the inerrupts.*/
LPSPI_FlushFifo(base, true, true);
LPSPI_ClearStatusFlags(base, kLPSPI_AllStatusFlag);
LPSPI_DisableInterrupts(base, kLPSPI_AllInterruptEnable);
/* If there is not rxData , can mask the receive data (receive data is not stored in receive FIFO).
* For master transfer , we'd better not masked the transmit data in TCR since the transfer flow is hard to
* controlled by software.*/
if (handle->rxData == NULL)
{
isRxMask = true;
handle->rxRemainingByteCount = 0;
}
base->TCR =
(base->TCR & ~(LPSPI_TCR_CONT_MASK | LPSPI_TCR_CONTC_MASK | LPSPI_TCR_RXMSK_MASK | LPSPI_TCR_PCS_MASK)) |
LPSPI_TCR_CONT(handle->isPcsContinuous) | LPSPI_TCR_CONTC(0) | LPSPI_TCR_RXMSK(isRxMask) |
LPSPI_TCR_PCS(whichPcs);
/*Calculate the bytes for write/read the TX/RX register each time*/
if (bytesPerFrame <= 4)
{
handle->bytesEachWrite = bytesPerFrame;
handle->bytesEachRead = bytesPerFrame;
}
else
{
handle->bytesEachWrite = 4;
handle->bytesEachRead = 4;
}
/* Enable the NVIC for LPSPI peripheral. Note that below code is useless if the LPSPI interrupt is in INTMUX ,
* and you should also enable the INTMUX interupt in your application.
*/
EnableIRQ(s_lpspiIRQ[LPSPI_GetInstance(base)]);
/*TCR is also shared the FIFO , so wait for TCR written.*/
while (LPSPI_GetTxFifoCount(base) != 0)
{
}
/*Fill up the TX data in FIFO */
LPSPI_MasterTransferFillUpTxFifo(base, handle);
/* Since SPI is a synchronous interface, we only need to enable the RX interrupt if there is RX data.
* The IRQ handler will get the status of RX and TX interrupt flags.
*/
if (handle->rxData)
{
/*Set rxWatermark to (readRegRemainingTimes-1) if readRegRemainingTimes less than rxWatermark. Otherwise there
*is not RX interrupt for the last datas because the RX count is not greater than rxWatermark.
*/
if ((handle->readRegRemainingTimes) <= handle->rxWatermark)
{
base->FCR = (base->FCR & (~LPSPI_FCR_RXWATER_MASK)) | LPSPI_FCR_RXWATER(handle->readRegRemainingTimes - 1);
}
LPSPI_EnableInterrupts(base, kLPSPI_RxInterruptEnable);
}
else
{
LPSPI_EnableInterrupts(base, kLPSPI_TxInterruptEnable);
}
return kStatus_Success;
}
static void LPSPI_MasterTransferFillUpTxFifo(LPSPI_Type *base, lpspi_master_handle_t *handle)
{
assert(handle);
uint32_t wordToSend = 0;
/* Make sure the difference in remaining TX and RX byte counts does not exceed FIFO depth
* and that the number of TX FIFO entries does not exceed the FIFO depth.
* But no need to make the protection if there is no rxData.
*/
while ((LPSPI_GetTxFifoCount(base) < (handle->fifoSize)) &&
(((handle->readRegRemainingTimes - handle->writeRegRemainingTimes) < handle->fifoSize) ||
(handle->rxData == NULL)))
{
if (handle->txRemainingByteCount < handle->bytesEachWrite)
{
handle->bytesEachWrite = handle->txRemainingByteCount;
}
if (handle->txData)
{
wordToSend = LPSPI_CombineWriteData(handle->txData, handle->bytesEachWrite, handle->isByteSwap);
handle->txData += handle->bytesEachWrite;
}
else
{
wordToSend = handle->txBuffIfNull;
}
/*Write the word to TX register*/
LPSPI_WriteData(base, wordToSend);
/*Decrease the write TX register times.*/
--handle->writeRegRemainingTimes;
/*Decrease the remaining TX byte count.*/
handle->txRemainingByteCount -= handle->bytesEachWrite;
if (handle->txRemainingByteCount == 0)
{
/* If PCS is continuous, update TCR to de-assert PCS */
if (handle->isPcsContinuous)
{
/* Only write to the TCR if the FIFO has room */
if ((LPSPI_GetTxFifoCount(base) < (handle->fifoSize)))
{
base->TCR = (base->TCR & ~(LPSPI_TCR_CONTC_MASK));
handle->writeTcrInIsr = false;
}
/* Else, set a global flag to tell the ISR to do write to the TCR */
else
{
handle->writeTcrInIsr = true;
}
}
break;
}
}
}
static void LPSPI_MasterTransferComplete(LPSPI_Type *base, lpspi_master_handle_t *handle)
{
assert(handle);
/* Disable interrupt requests*/
LPSPI_DisableInterrupts(base, kLPSPI_AllInterruptEnable);
handle->state = kLPSPI_Idle;
if (handle->callback)
{
handle->callback(base, handle, kStatus_Success, handle->userData);
}
}
/*!
* brief Gets the master transfer remaining bytes.
*
* This function gets the master transfer remaining bytes.
*
* param base LPSPI peripheral address.
* param handle pointer to lpspi_master_handle_t structure which stores the transfer state.
* param count Number of bytes transferred so far by the non-blocking transaction.
* return status of status_t.
*/
status_t LPSPI_MasterTransferGetCount(LPSPI_Type *base, lpspi_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 != kLPSPI_Busy)
{
*count = 0;
return kStatus_NoTransferInProgress;
}
size_t remainingByte;
if (handle->rxData)
{
remainingByte = handle->rxRemainingByteCount;
}
else
{
remainingByte = handle->txRemainingByteCount;
}
*count = handle->totalByteCount - remainingByte;
return kStatus_Success;
}
/*!
* brief LPSPI master abort transfer which uses an interrupt method.
*
* This function aborts a transfer which uses an interrupt method.
*
* param base LPSPI peripheral address.
* param handle pointer to lpspi_master_handle_t structure which stores the transfer state.
*/
void LPSPI_MasterTransferAbort(LPSPI_Type *base, lpspi_master_handle_t *handle)
{
assert(handle);
/* Disable interrupt requests*/
LPSPI_DisableInterrupts(base, kLPSPI_AllInterruptEnable);
LPSPI_Reset(base);
handle->state = kLPSPI_Idle;
handle->txRemainingByteCount = 0;
handle->rxRemainingByteCount = 0;
}
/*!
* brief LPSPI Master IRQ handler function.
*
* This function processes the LPSPI transmit and receive IRQ.
*
* param base LPSPI peripheral address.
* param handle pointer to lpspi_master_handle_t structure which stores the transfer state.
*/
void LPSPI_MasterTransferHandleIRQ(LPSPI_Type *base, lpspi_master_handle_t *handle)
{
assert(handle);
uint32_t readData;
if (handle->rxData != NULL)
{
if (handle->rxRemainingByteCount)
{
/* First, disable the interrupts to avoid potentially triggering another interrupt
* while reading out the RX FIFO as more data may be coming into the RX FIFO. We'll
* re-enable the interrupts based on the LPSPI state after reading out the FIFO.
*/
LPSPI_DisableInterrupts(base, kLPSPI_RxInterruptEnable);
while ((LPSPI_GetRxFifoCount(base)) && (handle->rxRemainingByteCount))
{
/*Read out the data*/
readData = LPSPI_ReadData(base);
/*Decrease the read RX register times.*/
--handle->readRegRemainingTimes;
if (handle->rxRemainingByteCount < handle->bytesEachRead)
{
handle->bytesEachRead = handle->rxRemainingByteCount;
}
LPSPI_SeparateReadData(handle->rxData, readData, handle->bytesEachRead, handle->isByteSwap);
handle->rxData += handle->bytesEachRead;
/*Decrease the remaining RX byte count.*/
handle->rxRemainingByteCount -= handle->bytesEachRead;
}
/* Re-enable the interrupts only if rxCount indicates there is more data to receive,
* else we may get a spurious interrupt.
* */
if (handle->rxRemainingByteCount)
{
/* Set the TDF and RDF interrupt enables simultaneously to avoid race conditions */
LPSPI_EnableInterrupts(base, kLPSPI_RxInterruptEnable);
}
}
/*Set rxWatermark to (readRegRemainingTimes-1) if readRegRemainingTimes less than rxWatermark. Otherwise there
*is not RX interrupt for the last datas because the RX count is not greater than rxWatermark.
*/
if ((handle->readRegRemainingTimes) <= (handle->rxWatermark))
{
base->FCR =
(base->FCR & (~LPSPI_FCR_RXWATER_MASK)) |
LPSPI_FCR_RXWATER((handle->readRegRemainingTimes > 1) ? (handle->readRegRemainingTimes - 1U) : (0U));
}
}
if (handle->txRemainingByteCount)
{
LPSPI_MasterTransferFillUpTxFifo(base, handle);
}
else
{
if ((LPSPI_GetTxFifoCount(base) < (handle->fifoSize)))
{
if ((handle->isPcsContinuous) && (handle->writeTcrInIsr))
{
base->TCR = (base->TCR & ~(LPSPI_TCR_CONTC_MASK));
handle->writeTcrInIsr = false;
}
}
}
if ((handle->txRemainingByteCount == 0) && (handle->rxRemainingByteCount == 0) && (!handle->writeTcrInIsr))
{
/* If no RX buffer, then transfer is not complete until transfer complete flag sets */
if (handle->rxData == NULL)
{
if (LPSPI_GetStatusFlags(base) & kLPSPI_TransferCompleteFlag)
{
/* Complete the transfer and disable the interrupts */
LPSPI_MasterTransferComplete(base, handle);
}
else
{
LPSPI_EnableInterrupts(base, kLPSPI_TransferCompleteInterruptEnable);
LPSPI_DisableInterrupts(base, kLPSPI_TxInterruptEnable | kLPSPI_RxInterruptEnable);
}
}
else
{
/* Complete the transfer and disable the interrupts */
LPSPI_MasterTransferComplete(base, handle);
}
}
}
/*Transactional APIs -- Slave*/
/*!
* brief Initializes the LPSPI slave handle.
*
* This function initializes the LPSPI handle, which can be used for other LPSPI transactional APIs. Usually, for a
* specified LPSPI instance, call this API once to get the initialized handle.
*
* param base LPSPI peripheral address.
* param handle LPSPI handle pointer to lpspi_slave_handle_t.
* param callback DSPI callback.
* param userData callback function parameter.
*/
void LPSPI_SlaveTransferCreateHandle(LPSPI_Type *base,
lpspi_slave_handle_t *handle,
lpspi_slave_transfer_callback_t callback,
void *userData)
{
assert(handle);
/* Zero the handle. */
memset(handle, 0, sizeof(*handle));
s_lpspiHandle[LPSPI_GetInstance(base)] = handle;
/* Set irq handler. */
s_lpspiSlaveIsr = LPSPI_SlaveTransferHandleIRQ;
handle->callback = callback;
handle->userData = userData;
}
/*!
* brief LPSPI slave transfer data using an interrupt method.
*
* This function transfer data using an interrupt method. This is a non-blocking function, which returns right away.
* When all data
* is transferred, the callback function is called.
*
* Note:
* The transfer data size should be integer multiples of bytesPerFrame if bytesPerFrame is less than or equal to 4.
* For bytesPerFrame greater than 4:
* The transfer data size should be equal to bytesPerFrame if the bytesPerFrame is not an integer multiple of 4.
* Otherwise, the transfer data size can be an integer multiple of bytesPerFrame.
*
* param base LPSPI peripheral address.
* param handle pointer to lpspi_slave_handle_t structure which stores the transfer state.
* param transfer pointer to lpspi_transfer_t structure.
* return status of status_t.
*/
status_t LPSPI_SlaveTransferNonBlocking(LPSPI_Type *base, lpspi_slave_handle_t *handle, lpspi_transfer_t *transfer)
{
assert(handle);
assert(transfer);
uint32_t bitsPerFrame = ((base->TCR & LPSPI_TCR_FRAMESZ_MASK) >> LPSPI_TCR_FRAMESZ_SHIFT) + 1;
uint32_t bytesPerFrame = (bitsPerFrame + 7) / 8;
uint32_t temp = 0U;
if (!LPSPI_CheckTransferArgument(transfer, bitsPerFrame, bytesPerFrame))
{
return kStatus_InvalidArgument;
}
/* Check that we're not busy.*/
if (handle->state == kLPSPI_Busy)
{
return kStatus_LPSPI_Busy;
}
handle->state = kLPSPI_Busy;
bool isRxMask = false;
bool isTxMask = false;
uint32_t whichPcs = (transfer->configFlags & LPSPI_SLAVE_PCS_MASK) >> LPSPI_SLAVE_PCS_SHIFT;
handle->txData = transfer->txData;
handle->rxData = transfer->rxData;
handle->txRemainingByteCount = transfer->dataSize;
handle->rxRemainingByteCount = transfer->dataSize;
handle->totalByteCount = transfer->dataSize;
handle->writeRegRemainingTimes = (transfer->dataSize / bytesPerFrame) * ((bytesPerFrame + 3) / 4);
handle->readRegRemainingTimes = handle->writeRegRemainingTimes;
/*The TX and RX FIFO sizes are always the same*/
handle->fifoSize = LPSPI_GetRxFifoSize(base);
handle->isByteSwap = (bool)(transfer->configFlags & kLPSPI_SlaveByteSwap);
/*Set the RX and TX watermarks to reduce the ISR times.*/
uint8_t txWatermark;
if (handle->fifoSize > 1)
{
txWatermark = 1;
handle->rxWatermark = handle->fifoSize - 2;
}
else
{
txWatermark = 0;
handle->rxWatermark = 0;
}
LPSPI_SetFifoWatermarks(base, txWatermark, handle->rxWatermark);
/* Check if using 3-wire mode and the txData is NULL, set the output pin to tristated. */
temp = base->CFGR1;
temp &= LPSPI_CFGR1_PINCFG_MASK;
if ((temp == LPSPI_CFGR1_PINCFG(kLPSPI_SdiInSdiOut)) || (temp == LPSPI_CFGR1_PINCFG(kLPSPI_SdoInSdoOut)))
{
if (!handle->txData)
{
LPSPI_Enable(base, false);
base->CFGR1 |= LPSPI_CFGR1_OUTCFG_MASK;
LPSPI_Enable(base, true);
}
/* The 3-wire mode can't send and receive data at the same time. */
if ((handle->txData) && (handle->rxData))
{
return kStatus_InvalidArgument;
}
}
/*Flush FIFO , clear status , disable all the inerrupts.*/
LPSPI_FlushFifo(base, true, true);
LPSPI_ClearStatusFlags(base, kLPSPI_AllStatusFlag);
LPSPI_DisableInterrupts(base, kLPSPI_AllInterruptEnable);
/*If there is not rxData , can mask the receive data (receive data is not stored in receive FIFO).*/
if (handle->rxData == NULL)
{
isRxMask = true;
handle->rxRemainingByteCount = 0;
}
/*If there is not txData , can mask the transmit data (no data is loaded from transmit FIFO and output pin
* is tristated).
*/
if (handle->txData == NULL)
{
isTxMask = true;
handle->txRemainingByteCount = 0;
}
base->TCR = (base->TCR &
~(LPSPI_TCR_CONT_MASK | LPSPI_TCR_CONTC_MASK | LPSPI_TCR_RXMSK_MASK | LPSPI_TCR_TXMSK_MASK |
LPSPI_TCR_PCS_MASK)) |
LPSPI_TCR_CONT(0) | LPSPI_TCR_CONTC(0) | LPSPI_TCR_RXMSK(isRxMask) | LPSPI_TCR_TXMSK(isTxMask) |
LPSPI_TCR_PCS(whichPcs);
/*Calculate the bytes for write/read the TX/RX register each time*/
if (bytesPerFrame <= 4)
{
handle->bytesEachWrite = bytesPerFrame;
handle->bytesEachRead = bytesPerFrame;
}
else
{
handle->bytesEachWrite = 4;
handle->bytesEachRead = 4;
}
/* Enable the NVIC for LPSPI peripheral. Note that below code is useless if the LPSPI interrupt is in INTMUX ,
* and you should also enable the INTMUX interupt in your application.
*/
EnableIRQ(s_lpspiIRQ[LPSPI_GetInstance(base)]);
/*TCR is also shared the FIFO , so wait for TCR written.*/
while (LPSPI_GetTxFifoCount(base) != 0)
{
}
/*Fill up the TX data in FIFO */
if (handle->txData)
{
LPSPI_SlaveTransferFillUpTxFifo(base, handle);
}
/* Since SPI is a synchronous interface, we only need to enable the RX interrupt if there is RX data.
* The IRQ handler will get the status of RX and TX interrupt flags.
*/
if (handle->rxData)
{
/*Set rxWatermark to (readRegRemainingTimes-1) if readRegRemainingTimes less than rxWatermark. Otherwise there
*is not RX interrupt for the last datas because the RX count is not greater than rxWatermark.
*/
if ((handle->readRegRemainingTimes) <= handle->rxWatermark)
{
base->FCR = (base->FCR & (~LPSPI_FCR_RXWATER_MASK)) | LPSPI_FCR_RXWATER(handle->readRegRemainingTimes - 1);
}
LPSPI_EnableInterrupts(base, kLPSPI_RxInterruptEnable);
}
else
{
LPSPI_EnableInterrupts(base, kLPSPI_TxInterruptEnable);
}
if (handle->rxData)
{
/* RX FIFO overflow request enable */
LPSPI_EnableInterrupts(base, kLPSPI_ReceiveErrorInterruptEnable);
}
if (handle->txData)
{
/* TX FIFO underflow request enable */
LPSPI_EnableInterrupts(base, kLPSPI_TransmitErrorInterruptEnable);
}
return kStatus_Success;
}
static void LPSPI_SlaveTransferFillUpTxFifo(LPSPI_Type *base, lpspi_slave_handle_t *handle)
{
assert(handle);
uint32_t wordToSend = 0;
while (LPSPI_GetTxFifoCount(base) < (handle->fifoSize))
{
if (handle->txRemainingByteCount < handle->bytesEachWrite)
{
handle->bytesEachWrite = handle->txRemainingByteCount;
}
wordToSend = LPSPI_CombineWriteData(handle->txData, handle->bytesEachWrite, handle->isByteSwap);
handle->txData += handle->bytesEachWrite;
/*Decrease the remaining TX byte count.*/
handle->txRemainingByteCount -= handle->bytesEachWrite;
/*Write the word to TX register*/
LPSPI_WriteData(base, wordToSend);
if (handle->txRemainingByteCount == 0)
{
break;
}
}
}
static void LPSPI_SlaveTransferComplete(LPSPI_Type *base, lpspi_slave_handle_t *handle)
{
assert(handle);
status_t status = 0;
/* Disable interrupt requests*/
LPSPI_DisableInterrupts(base, kLPSPI_AllInterruptEnable);
if (handle->state == kLPSPI_Error)
{
status = kStatus_LPSPI_Error;
}
else
{
status = kStatus_Success;
}
handle->state = kLPSPI_Idle;
if (handle->callback)
{
handle->callback(base, handle, status, handle->userData);
}
}
/*!
* brief Gets the slave transfer remaining bytes.
*
* This function gets the slave transfer remaining bytes.
*
* param base LPSPI peripheral address.
* param handle pointer to lpspi_slave_handle_t structure which stores the transfer state.
* param count Number of bytes transferred so far by the non-blocking transaction.
* return status of status_t.
*/
status_t LPSPI_SlaveTransferGetCount(LPSPI_Type *base, lpspi_slave_handle_t *handle, size_t *count)
{
assert(handle);
if (!count)
{
return kStatus_InvalidArgument;
}
/* Catch when there is not an active transfer. */
if (handle->state != kLPSPI_Busy)
{
*count = 0;
return kStatus_NoTransferInProgress;
}
size_t remainingByte;
if (handle->rxData)
{
remainingByte = handle->rxRemainingByteCount;
}
else
{
remainingByte = handle->txRemainingByteCount;
}
*count = handle->totalByteCount - remainingByte;
return kStatus_Success;
}
/*!
* brief LPSPI slave aborts a transfer which uses an interrupt method.
*
* This function aborts a transfer which uses an interrupt method.
*
* param base LPSPI peripheral address.
* param handle pointer to lpspi_slave_handle_t structure which stores the transfer state.
*/
void LPSPI_SlaveTransferAbort(LPSPI_Type *base, lpspi_slave_handle_t *handle)
{
assert(handle);
/* Disable interrupt requests*/
LPSPI_DisableInterrupts(base, kLPSPI_TxInterruptEnable | kLPSPI_RxInterruptEnable);
LPSPI_Reset(base);
handle->state = kLPSPI_Idle;
handle->txRemainingByteCount = 0;
handle->rxRemainingByteCount = 0;
}
/*!
* brief LPSPI Slave IRQ handler function.
*
* This function processes the LPSPI transmit and receives an IRQ.
*
* param base LPSPI peripheral address.
* param handle pointer to lpspi_slave_handle_t structure which stores the transfer state.
*/
void LPSPI_SlaveTransferHandleIRQ(LPSPI_Type *base, lpspi_slave_handle_t *handle)
{
assert(handle);
uint32_t readData; /* variable to store word read from RX FIFO */
uint32_t wordToSend; /* variable to store word to write to TX FIFO */
if (handle->rxData != NULL)
{
if (handle->rxRemainingByteCount > 0)
{
while (LPSPI_GetRxFifoCount(base))
{
/*Read out the data*/
readData = LPSPI_ReadData(base);
/*Decrease the read RX register times.*/
--handle->readRegRemainingTimes;
if (handle->rxRemainingByteCount < handle->bytesEachRead)
{
handle->bytesEachRead = handle->rxRemainingByteCount;
}
LPSPI_SeparateReadData(handle->rxData, readData, handle->bytesEachRead, handle->isByteSwap);
handle->rxData += handle->bytesEachRead;
/*Decrease the remaining RX byte count.*/
handle->rxRemainingByteCount -= handle->bytesEachRead;
if ((handle->txRemainingByteCount > 0) && (handle->txData != NULL))
{
if (handle->txRemainingByteCount < handle->bytesEachWrite)
{
handle->bytesEachWrite = handle->txRemainingByteCount;
}
wordToSend = LPSPI_CombineWriteData(handle->txData, handle->bytesEachWrite, handle->isByteSwap);
handle->txData += handle->bytesEachWrite;
/*Decrease the remaining TX byte count.*/
handle->txRemainingByteCount -= handle->bytesEachWrite;
/*Write the word to TX register*/
LPSPI_WriteData(base, wordToSend);
}
if (handle->rxRemainingByteCount == 0)
{
break;
}
}
}
/*Set rxWatermark to (readRegRemainingTimes-1) if readRegRemainingTimes less than rxWatermark. Otherwise there
*is not RX interrupt for the last datas because the RX count is not greater than rxWatermark.
*/
if ((handle->readRegRemainingTimes) <= (handle->rxWatermark))
{
base->FCR =
(base->FCR & (~LPSPI_FCR_RXWATER_MASK)) |
LPSPI_FCR_RXWATER((handle->readRegRemainingTimes > 1) ? (handle->readRegRemainingTimes - 1U) : (0U));
}
}
else if ((handle->txRemainingByteCount) && (handle->txData != NULL))
{
LPSPI_SlaveTransferFillUpTxFifo(base, handle);
}
else
{
__NOP();
}
if ((handle->txRemainingByteCount == 0) && (handle->rxRemainingByteCount == 0))
{
/* If no RX buffer, then transfer is not complete until transfer complete flag sets and the TX FIFO empty*/
if (handle->rxData == NULL)
{
if ((LPSPI_GetStatusFlags(base) & kLPSPI_FrameCompleteFlag) && (LPSPI_GetTxFifoCount(base) == 0))
{
/* Complete the transfer and disable the interrupts */
LPSPI_SlaveTransferComplete(base, handle);
}
else
{
LPSPI_ClearStatusFlags(base, kLPSPI_FrameCompleteFlag);
LPSPI_EnableInterrupts(base, kLPSPI_FrameCompleteInterruptEnable);
LPSPI_DisableInterrupts(base, kLPSPI_TxInterruptEnable | kLPSPI_RxInterruptEnable);
}
}
else
{
/* Complete the transfer and disable the interrupts */
LPSPI_SlaveTransferComplete(base, handle);
}
}
/* Catch tx fifo underflow conditions, service only if tx under flow interrupt enabled */
if ((LPSPI_GetStatusFlags(base) & kLPSPI_TransmitErrorFlag) && (base->IER & LPSPI_IER_TEIE_MASK))
{
LPSPI_ClearStatusFlags(base, kLPSPI_TransmitErrorFlag);
/* Change state to error and clear flag */
if (handle->txData)
{
handle->state = kLPSPI_Error;
}
handle->errorCount++;
}
/* Catch rx fifo overflow conditions, service only if rx over flow interrupt enabled */
if ((LPSPI_GetStatusFlags(base) & kLPSPI_ReceiveErrorFlag) && (base->IER & LPSPI_IER_REIE_MASK))
{
LPSPI_ClearStatusFlags(base, kLPSPI_ReceiveErrorFlag);
/* Change state to error and clear flag */
if (handle->txData)
{
handle->state = kLPSPI_Error;
}
handle->errorCount++;
}
}
static uint32_t LPSPI_CombineWriteData(uint8_t *txData, uint32_t bytesEachWrite, bool isByteSwap)
{
assert(txData);
uint32_t wordToSend = 0;
switch (bytesEachWrite)
{
case 1:
wordToSend = *txData;
++txData;
break;
case 2:
if (!isByteSwap)
{
wordToSend = *txData;
++txData;
wordToSend |= (unsigned)(*txData) << 8U;
++txData;
}
else
{
wordToSend = (unsigned)(*txData) << 8U;
++txData;
wordToSend |= *txData;
++txData;
}
break;
case 3:
if (!isByteSwap)
{
wordToSend = *txData;
++txData;
wordToSend |= (unsigned)(*txData) << 8U;
++txData;
wordToSend |= (unsigned)(*txData) << 16U;
++txData;
}
else
{
wordToSend = (unsigned)(*txData) << 16U;
++txData;
wordToSend |= (unsigned)(*txData) << 8U;
++txData;
wordToSend |= *txData;
++txData;
}
break;
case 4:
if (!isByteSwap)
{
wordToSend = *txData;
++txData;
wordToSend |= (unsigned)(*txData) << 8U;
++txData;
wordToSend |= (unsigned)(*txData) << 16U;
++txData;
wordToSend |= (unsigned)(*txData) << 24U;
++txData;
}
else
{
wordToSend = (unsigned)(*txData) << 24U;
++txData;
wordToSend |= (unsigned)(*txData) << 16U;
++txData;
wordToSend |= (unsigned)(*txData) << 8U;
++txData;
wordToSend |= *txData;
++txData;
}
break;
default:
assert(false);
break;
}
return wordToSend;
}
static void LPSPI_SeparateReadData(uint8_t *rxData, uint32_t readData, uint32_t bytesEachRead, bool isByteSwap)
{
assert(rxData);
switch (bytesEachRead)
{
case 1:
*rxData = readData;
++rxData;
break;
case 2:
if (!isByteSwap)
{
*rxData = readData;
++rxData;
*rxData = readData >> 8;
++rxData;
}
else
{
*rxData = readData >> 8;
++rxData;
*rxData = readData;
++rxData;
}
break;
case 3:
if (!isByteSwap)
{
*rxData = readData;
++rxData;
*rxData = readData >> 8;
++rxData;
*rxData = readData >> 16;
++rxData;
}
else
{
*rxData = readData >> 16;
++rxData;
*rxData = readData >> 8;
++rxData;
*rxData = readData;
++rxData;
}
break;
case 4:
if (!isByteSwap)
{
*rxData = readData;
++rxData;
*rxData = readData >> 8;
++rxData;
*rxData = readData >> 16;
++rxData;
*rxData = readData >> 24;
++rxData;
}
else
{
*rxData = readData >> 24;
++rxData;
*rxData = readData >> 16;
++rxData;
*rxData = readData >> 8;
++rxData;
*rxData = readData;
++rxData;
}
break;
default:
assert(false);
break;
}
}
static void LPSPI_CommonIRQHandler(LPSPI_Type *base, void *param)
{
if (LPSPI_IsMaster(base))
{
s_lpspiMasterIsr(base, (lpspi_master_handle_t *)param);
}
else
{
s_lpspiSlaveIsr(base, (lpspi_slave_handle_t *)param);
}
/* 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(LPSPI0)
void LPSPI0_DriverIRQHandler(void)
{
assert(s_lpspiHandle[0]);
LPSPI_CommonIRQHandler(LPSPI0, s_lpspiHandle[0]);
}
#endif
#if defined(LPSPI1)
void LPSPI1_DriverIRQHandler(void)
{
assert(s_lpspiHandle[1]);
LPSPI_CommonIRQHandler(LPSPI1, s_lpspiHandle[1]);
}
#endif
#if defined(LPSPI2)
void LPSPI2_DriverIRQHandler(void)
{
assert(s_lpspiHandle[2]);
LPSPI_CommonIRQHandler(LPSPI2, s_lpspiHandle[2]);
}
#endif
#if defined(LPSPI3)
void LPSPI3_DriverIRQHandler(void)
{
assert(s_lpspiHandle[3]);
LPSPI_CommonIRQHandler(LPSPI3, s_lpspiHandle[3]);
}
#endif
#if defined(LPSPI4)
void LPSPI4_DriverIRQHandler(void)
{
assert(s_lpspiHandle[4]);
LPSPI_CommonIRQHandler(LPSPI4, s_lpspiHandle[4]);
}
#endif
#if defined(LPSPI5)
void LPSPI5_DriverIRQHandler(void)
{
assert(s_lpspiHandle[5]);
LPSPI_CommonIRQHandler(LPSPI5, s_lpspiHandle[5]);
}
#endif
#if defined(DMA__LPSPI0)
void DMA_SPI0_INT_DriverIRQHandler(void)
{
assert(s_lpspiHandle[LPSPI_GetInstance(DMA__LPSPI0)]);
LPSPI_CommonIRQHandler(DMA__LPSPI0, s_lpspiHandle[LPSPI_GetInstance(DMA__LPSPI0)]);
}
#endif
#if defined(DMA__LPSPI1)
void DMA_SPI1_INT_DriverIRQHandler(void)
{
assert(s_lpspiHandle[LPSPI_GetInstance(DMA__LPSPI1)]);
LPSPI_CommonIRQHandler(DMA__LPSPI1, s_lpspiHandle[LPSPI_GetInstance(DMA__LPSPI1)]);
}
#endif
#if defined(DMA__LPSPI2)
void DMA_SPI2_INT_DriverIRQHandler(void)
{
assert(s_lpspiHandle[LPSPI_GetInstance(DMA__LPSPI2)]);
LPSPI_CommonIRQHandler(DMA__LPSPI2, s_lpspiHandle[LPSPI_GetInstance(DMA__LPSPI2)]);
}
#endif
#if defined(DMA__LPSPI3)
void DMA_SPI3_INT_DriverIRQHandler(void)
{
assert(s_lpspiHandle[LPSPI_GetInstance(DMA__LPSPI3)]);
LPSPI_CommonIRQHandler(DMA__LPSPI3, s_lpspiHandle[LPSPI_GetInstance(DMA__LPSPI3)]);
}
#endif
#if defined(ADMA__LPSPI0)
void ADMA_SPI0_INT_DriverIRQHandler(void)
{
assert(s_lpspiHandle[LPSPI_GetInstance(ADMA__LPSPI0)]);
LPSPI_CommonIRQHandler(ADMA__LPSPI0, s_lpspiHandle[LPSPI_GetInstance(ADMA__LPSPI0)]);
}
#endif
#if defined(ADMA__LPSPI1)
void ADMA_SPI1_INT_DriverIRQHandler(void)
{
assert(s_lpspiHandle[LPSPI_GetInstance(ADMA__LPSPI1)]);
LPSPI_CommonIRQHandler(ADMA__LPSPI1, s_lpspiHandle[LPSPI_GetInstance(ADMA__LPSPI1)]);
}
#endif
#if defined(ADMA__LPSPI2)
void ADMA_SPI2_INT_DriverIRQHandler(void)
{
assert(s_lpspiHandle[LPSPI_GetInstance(ADMA__LPSPI2)]);
LPSPI_CommonIRQHandler(ADMA__LPSPI2, s_lpspiHandle[LPSPI_GetInstance(ADMA__LPSPI2)]);
}
#endif
#if defined(ADMA__LPSPI3)
void ADMA_SPI3_INT_DriverIRQHandler(void)
{
assert(s_lpspiHandle[LPSPI_GetInstance(ADMA__LPSPI3)]);
LPSPI_CommonIRQHandler(ADMA__LPSPI3, s_lpspiHandle[LPSPI_GetInstance(ADMA__LPSPI3)]);
}
#endif
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