KED/ked/drivers/spi.c

#include "spi.h"

// generic implementation of spi channel class

void spiSetupCH(spi_ch_t *ch, spiCH_t spi_hw_ch, pinNo_t chipselectPin)
{
	ch->pin  = chipselectPin;
	ch->spi = spi_hw_ch;
	pinWrite(chipselectPin, 0);
}

uint8_t spiReadReg(spi_ch_t *spi_ch,
					  uint8_t reg_address) {
	uint8_t buf;
	
	// select target device
	pinWrite(spi_ch->pin,0);
	
	// send address of target register
	spiTrx(spi_ch->spi, reg_address);

	// read from target register
	buf = spiTrx(spi_ch->spi,0x00);

	// release target device
	pinWrite(spi_ch->pin,1);

	return buf;
}

void spiAutoReadBlock(spi_ch_t *spi_ch,
						 uint8_t start_address,
						 uint8_t* buffer,
						 uint8_t buf_len) {
	uint8_t i = 0;

	// select target device
	pinWrite(spi_ch->pin,0);
	
	// send address of starting register
	spiTrx(spi_ch->spi, start_address);

	// read block from device
	for(;i < buf_len;i++) {
		buffer[i] = spiTrx(spi_ch->spi, 0x00);
	}

	// release target device
	pinWrite(spi_ch->pin,1);
}

void spiWriteReg(spi_ch_t *spi_ch,
					uint8_t reg_address,
					uint8_t data) {
	// select target device
	pinWrite(spi_ch->pin,0);
	
	// send address of target register
	spiTrx(spi_ch->spi, reg_address);

	// write to target register
	spiTrx(spi_ch->spi, data);

	// release target device
	pinWrite(spi_ch->pin,1);
}

void spiWriteBlock(spi_ch_t *spi_ch,
					  uint8_t start_address,
					  const uint8_t *data,
					  uint8_t data_len) {
	uint8_t i = 0;

	// select target device
	pinWrite(spi_ch->pin,0);
	
	// send address of starting register
	spiTrx(spi_ch->spi, start_address);

	// read block from device
	for(;i < data_len;i++) {
		spiTrx(spi_ch->spi, data[i]);
	}

	// release target device
	pinWrite(spi_ch->pin,1);
}

void spiWrite8bit(spi_ch_t *spi_ch,
					uint8_t bits)
{
	pinWrite(spi_ch->pin,0);
	spiTrx(spi_ch->spi,bits);
	pinWrite(spi_ch->pin,1);
}

uint8_t spiReadWrite8bit(spi_ch_t *spi_ch,
							uint8_t bits)
{
	uint8_t buf;
	pinWrite(spi_ch->pin,0);
	buf = spiTrx(spi_ch->spi,bits);
	pinWrite(spi_ch->pin,1);
	return buf;
}

void spiWrite16bit(spi_ch_t *spi_ch,
					uint16_t bits)
{
	pinWrite(spi_ch->pin,0);
	if(spi_ch->format == LSB_FIRST) {
		spiTrx(spi_ch->spi,(uint8_t)(bits >> 8));
		spiTrx(spi_ch->spi,(uint8_t)(bits));
	} else {	
		spiTrx(spi_ch->spi,(uint8_t)(bits));
		spiTrx(spi_ch->spi,(uint8_t)(bits >> 8));
	}
	pinWrite(spi_ch->pin,1);
}

uint16_t spiReadWrite16bit(spi_ch_t *spi_ch,
							uint16_t bits)
{
	uint16_t buf;

	pinWrite(spi_ch->pin,0);
	if(spi_ch->format == LSB_FIRST) {
		buf = spiTrx(spi_ch->spi,(uint8_t)(bits >> 8)) << 8;
		buf |= spiTrx(spi_ch->spi,(uint8_t)(bits));
	} else {	
		buf = spiTrx(spi_ch->spi,(uint8_t)(bits));
		buf |= spiTrx(spi_ch->spi,(uint8_t)(bits >> 8)) << 8;
	}
	pinWrite(spi_ch->pin,1);
	
	return buf;
}

void spiWrite32bit(spi_ch_t *spi_ch,
					uint32_t bits)
{
	pinWrite(spi_ch->pin,0);
	if(spi_ch->format == LSB_FIRST) {
		spiTrx(spi_ch->spi,(uint8_t)(bits >> 32));
		spiTrx(spi_ch->spi,(uint8_t)(bits >> 16));
		spiTrx(spi_ch->spi,(uint8_t)(bits >> 8));
		spiTrx(spi_ch->spi,(uint8_t)(bits));
	} else {	
		spiTrx(spi_ch->spi,(uint8_t)(bits));
		spiTrx(spi_ch->spi,(uint8_t)(bits >> 8));
		spiTrx(spi_ch->spi,(uint8_t)(bits >> 16));
		spiTrx(spi_ch->spi,(uint8_t)(bits >> 32));
	}
	pinWrite(spi_ch->pin,1);
}

uint32_t spiReadWrite32bit(spi_ch_t *spi_ch,
							uint8_t bits)
{
	uint32_t buf;

	pinWrite(spi_ch->pin,0);
	if(spi_ch->format == LSB_FIRST) {
		buf = spiTrx(spi_ch->spi,(uint8_t)(bits >> 24)) << 24;
		buf |= spiTrx(spi_ch->spi,(uint8_t)(bits >> 16)) << 16;
		buf |= spiTrx(spi_ch->spi,(uint8_t)(bits >> 8)) << 8;
		buf |= spiTrx(spi_ch->spi,(uint8_t)(bits));
	} else {	
		buf = spiTrx(spi_ch->spi,(uint8_t)(bits));
		buf |= spiTrx(spi_ch->spi,(uint8_t)(bits >> 8)) >> 8;
		buf |= spiTrx(spi_ch->spi,(uint8_t)(bits >> 16)) >> 16;
		buf |= spiTrx(spi_ch->spi,(uint8_t)(bits >> 24)) >> 24;
	}
	pinWrite(spi_ch->pin,1);

	return buf;
}