Execute a single or combined i2c message
int i2c_transfer(struct i2c_adapter * adap, struct i2c_msg * msgs, int num);
adap
Handle to I2C bus
msgs
One or more messages to execute before STOP is issued to terminate the operation; each message begins with a START.
num
Number of messages to be executed.
Returns negative errno, else the number of messages executed.
Note that there is no requirement that each message be sent to the same slave address, although that is the most common model.