peripherals: add I2C lib [#2]

This commit is contained in:
Vasily Davydov 2023-04-04 22:24:43 +03:00
parent 4fda9a4128
commit 0f45c4adbb
2 changed files with 193 additions and 0 deletions

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/*
* I2C.cpp
*
* Created on: 21.2.2016
* Author: krl
* Based on example provided by NXP Semiconductors. See copyright notice
* below.
*/
/*
* @brief I2CM bus master example using polling mode
*
* @note
* Copyright(C) NXP Semiconductors, 2014
* All rights reserved.
*
* @par
* Software that is described herein is for illustrative purposes only
* which provides customers with programming information regarding the
* LPC products. This software is supplied "AS IS" without any warranties of
* any kind, and NXP Semiconductors and its licensor disclaim any and
* all warranties, express or implied, including all implied warranties of
* merchantability, fitness for a particular purpose and non-infringement of
* intellectual property rights. NXP Semiconductors assumes no responsibility
* or liability for the use of the software, conveys no license or rights under
* any patent, copyright, mask work right, or any other intellectual property
* rights in or to any products. NXP Semiconductors reserves the right to make
* changes in the software without notification. NXP Semiconductors also makes
* no representation or warranty that such application will be suitable for the
* specified use without further testing or modification.
*
* @par
* Permission to use, copy, modify, and distribute this software and its
* documentation is hereby granted, under NXP Semiconductors' and its
* licensor's relevant copyrights in the software, without fee, provided that
* it is used in conjunction with NXP Semiconductors microcontrollers. This
* copyright, permission, and disclaimer notice must appear in all copies of
* this code.
*/
#include "I2C.h"
I2C::I2C (const I2C_config &cfg) : device (nullptr)
{
// if(cfg.device_number == 0) {
device = LPC_I2C0;
// board init must have been called before the pins can be configured
Chip_IOCON_PinMuxSet (LPC_IOCON, 0, 22, IOCON_DIGMODE_EN | cfg.i2c_mode);
Chip_IOCON_PinMuxSet (LPC_IOCON, 0, 23, IOCON_DIGMODE_EN | cfg.i2c_mode);
Chip_SWM_EnableFixedPin (SWM_FIXED_I2C0_SCL);
Chip_SWM_EnableFixedPin (SWM_FIXED_I2C0_SDA);
//}
// else {
// currently we support only I2C number 0
//}
if (LPC_I2C0)
{
/* Enable I2C clock and reset I2C peripheral - the boot ROM does not
do this */
Chip_I2C_Init (LPC_I2C0);
/* Setup clock rate for I2C */
Chip_I2C_SetClockDiv (LPC_I2C0, cfg.clock_divider);
/* Setup I2CM transfer rate */
Chip_I2CM_SetBusSpeed (LPC_I2C0, cfg.speed);
/* Enable Master Mode */
Chip_I2CM_Enable (LPC_I2C0);
}
}
I2C::~I2C ()
{
// TODO Auto-generated destructor stub
}
bool
I2C::write (uint8_t devAddr, uint8_t *txBuffPtr, uint16_t txSize)
{
return transaction (devAddr, txBuffPtr, txSize, nullptr, 0);
}
bool
I2C::read (uint8_t devAddr, uint8_t *rxBuffPtr, uint16_t rxSize)
{
return transaction (devAddr, nullptr, 0, rxBuffPtr, rxSize);
}
bool
I2C::transaction (uint8_t devAddr, uint8_t *txBuffPtr, uint16_t txSize,
uint8_t *rxBuffPtr, uint16_t rxSize)
{
I2CM_XFER_T i2cmXferRec;
// make sure that master is idle
while (!Chip_I2CM_IsMasterPending (LPC_I2C0))
;
/* Setup I2C transfer record */
i2cmXferRec.slaveAddr = devAddr;
i2cmXferRec.status = 0;
i2cmXferRec.txSz = txSize;
i2cmXferRec.rxSz = rxSize;
i2cmXferRec.txBuff = txBuffPtr;
i2cmXferRec.rxBuff = rxBuffPtr;
I2CM_XferBlocking (LPC_I2C0, &i2cmXferRec);
// Chip_I2CM_XferBlocking returns before stop condition is fully completed
// therefore we need to wait for master to be idle when doing back-to-back
// transactions (see beginning of the function)
/* Test for valid operation */
if (i2cmXferRec.status == I2CM_STATUS_OK)
{
return true;
}
else
{
return false;
}
}
/* Transmit and Receive data in master mode */
/* This duplicates (and combines) the functionality of Chip_I2CM_Xfer and
* Chip_I2CM_XferBlocking with a modification that allows us to do a zero
* length write (needed to use honeywell humidity/temp sensor)
*/
uint32_t
I2C::I2CM_XferBlocking (LPC_I2C_T *pI2C, I2CM_XFER_T *xfer)
{
uint32_t ret = 0;
/* start transfer */
/* set the transfer status as busy */
xfer->status = I2CM_STATUS_BUSY;
/* Clear controller state. */
Chip_I2CM_ClearStatus (pI2C, I2C_STAT_MSTRARBLOSS | I2C_STAT_MSTSTSTPERR);
/* Write Address and RW bit to data register */
// Chip_I2CM_WriteByte(pI2C, (xfer->slaveAddr << 1) | (xfer->txSz == 0)); //
// original NXP version
// krl : both read and write lenght is 0 --> write (for honeywell temp
// sensor)
Chip_I2CM_WriteByte (pI2C, (xfer->slaveAddr << 1)
| (xfer->txSz == 0 && xfer->rxSz != 0));
/* Enter to Master Transmitter mode */
Chip_I2CM_SendStart (pI2C);
while (ret == 0)
{
/* wait for status change interrupt */
while (!Chip_I2CM_IsMasterPending (pI2C))
{
}
/* call state change handler */
ret = Chip_I2CM_XferHandler (pI2C, xfer);
}
return ret;
}

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/*
* I2C.h
*
* Created on: 21.2.2016
* Author: krl
*/
#ifndef I2C_H_
#define I2C_H_
#include "chip.h"
struct I2C_config {
unsigned int device_number;
unsigned int speed;
unsigned int clock_divider;
unsigned int i2c_mode;
I2C_config(unsigned int dn, unsigned int sp, unsigned int cd): device_number(dn), speed(sp), clock_divider(cd), i2c_mode(IOCON_SFI2C_EN) {};
};
class I2C {
public:
I2C(const I2C_config &cfg);
virtual ~I2C();
bool transaction(uint8_t devAddr, uint8_t *txBuffPtr, uint16_t txSize, uint8_t *rxBuffPtr, uint16_t rxSize);
bool write(uint8_t devAddr, uint8_t *txBuffPtr, uint16_t txSize);
bool read(uint8_t devAddr, uint8_t *rxBuffPtr, uint16_t rxSize);
private:
LPC_I2C_T *device;
static uint32_t I2CM_XferBlocking(LPC_I2C_T *pI2C, I2CM_XFER_T *xfer);
};
#endif /* I2C_H_ */