size_t i2c::command(uint8_t slaveaddr,
uint8_t cmd,
const uint8_t* data_addr,
size_t data_size)
{
reset_txfer_done();
set_slave_address(slaveaddr);
set_data_len(1 + data_size);
initiate_write();
write_byte(cmd);
size_t bytes_sent=1;
while (data_size>0)
{
if (write_byte(*data_addr))
{
data_addr++;
data_size--;
bytes_sent++;
}
// TODO check for error conditions
}
wait_for_done();
clear_fifo();
return bytes_sent;
}
bool I2C::write_word(uint8_t register_address, uint16_t value)
{
set_slave_address();
i2c_smbus_data data;
data.word = value;
return use_smbus_IOCTL(true, register_address, I2C_SMBUS_WORD_DATA, data);
}
bool I2C::write_byte(uint8_t register_address, uint8_t value)
{
set_slave_address();
i2c_smbus_data data;
data.byte = value;
return use_smbus_IOCTL(true, register_address, I2C_SMBUS_BYTE_DATA, data);
}
bool I2C::read_byte(uint8_t register_address, uint8_t& value)
{
set_slave_address();
i2c_smbus_data data;
if( use_smbus_IOCTL(false, register_address, I2C_SMBUS_BYTE_DATA, data) != 0)
{
value = data.byte;
return true;
}
else
{
return false;
}
}
uint8_t I2C::read_block(uint8_t register_address, uint8_t* value, size_t length)
{
set_slave_address();
if( length > I2C_SMBUS_BLOCK_MAX )
{
length = I2C_SMBUS_BLOCK_MAX;
}
i2c_smbus_data data;
data.block[0] = length;
if( use_smbus_IOCTL(false, register_address, I2C_SMBUS_I2C_BLOCK_DATA, data) )
{
memcpy(value, &(data.block[1]), length);
return data.block[0];
}
else
{
return 0;
}
}
uint8_t I2C::write_block(uint8_t register_address, uint8_t* value, size_t length)
{
set_slave_address();
if( length > I2C_SMBUS_BLOCK_MAX )
{
length = I2C_SMBUS_BLOCK_MAX;
}
i2c_smbus_data data;
memset(data.block, 0, length+1);
memcpy( &(data.block[1]), value, length);
data.block[0] = length;
if (use_smbus_IOCTL(true, register_address, I2C_SMBUS_I2C_BLOCK_DATA, data))
{
return length;
}
else
{
return 0;
}
}
