#include <stdio.h>

        #include <stdlib.h>

        #include <fcntl.h>

        #include <unistd.h>

        #include <math.h> 

        char iiotype[16][32] = {

                ''in_voltage0_raw'',

                'in_voltage1_raw',

                'in_voltage2_raw',

                'in_voltage3_raw',

                'in_voltage4_raw',

                'in_voltage5_raw',

                'in_voltage6_raw',

                'in_voltage7_raw'

    };

              

        // return = 0: voltage value from AIN0, unit: mV

        // < 0: failed

        int read_AIN0(float *fvoltage)

        {

                int value, ret = 0;

                char filename[80];

                FILE *fp;

                char buf[20];

                sprintf( filename, '/sys/bus/iio/devices/iio:device0/%s', iiotype[0]);

                fp = fopen(filename, 'rt' );

                if( fp==NULL )

                {

                        printf('open %s fail!\n', filename);

                        *fvoltage = 0.0;

                        ret = -1;

                        return ret;

                }

                fread( buf, 1, sizeof(buf), fp );

                fclose(fp);

        

                // convert to integer

                sscanf( buf, '%d', &value );

                *fvoltage = 0.8 * value;

                return ret;

        }

        // return = 0: voltage value from AIN2, unit: mV

        // < 0: failed

        int read_AIN2(float *fvoltage)

        {

                int value, ret = 0;

                char filename[80];

                FILE *fp;

                char buf[20];

                sprintf( filename, '/sys/bus/iio/devices/iio:device0/%s', iiotype[2]);

                fp = fopen(filename, 'rt' );

                if( fp==NULL )

                {

                        printf('open %s fail!\n', filename);

                        *fvoltage = 0.0;

                        ret = -1;

                        return ret;

                }

                fread( buf, 1, sizeof(buf), fp );

                fclose(fp);

                // convert to integer

                sscanf( buf, '%d', &value );

                *fvoltage = 0.8 * value;

                return ret;

        }

　　　// return = 0: voltage value from AIN3, unit: mV

        // < 0: failed

        int read_AIN3(float *fvoltage)

        {

                int value, ret = 0;

                char filename[80];

                FILE *fp;

                char buf[20];

                sprintf( filename, '/sys/bus/iio/devices/iio:device0/%s', iiotype[3]);

                fp = fopen(filename, 'rt' );

                if( fp==NULL )

                {

                        printf('open %s fail!\n', filename);

                        *fvoltage = 0.0;

                        ret = -1;

                        return ret;

                }

                fread( buf, 1, sizeof(buf), fp );

                fclose(fp);

                // convert to integer

                sscanf( buf, '%d', &value );

                *fvoltage = 0.8 * value;

                return ret;

        }

 

        // return = 0: voltage value from AIN4, unit: mV

        // < 0: failed

        int read_AIN4(float *fvoltage)

        {

                int value, ret = 0;

                char filename[80];

                FILE *fp;

                char buf[20];

                sprintf( filename, '/sys/bus/iio/devices/iio:device0/%s', iiotype[4]);

                fp = fopen(filename, 'rt' );

                if( fp==NULL )

                {

                        printf('open %s fail!\n', filename);

                        *fvoltage = 0.0;

                        ret = -1;

                        return ret;

                }

                fread( buf, 1, sizeof(buf), fp );

                fclose(fp);

                // convert to integer

                sscanf( buf, '%d', &value );

                *fvoltage = 0.8 * value;

                return ret;

        }

        // return = 0: voltage value from AIN5, unit: mV

        // < 0: failed

        int read_AIN5(float *fvoltage)

        {

                int value, ret = 0;

                char filename[80];

                FILE *fp;

                char buf[20];

                sprintf( filename, '/sys/bus/iio/devices/iio:device0/%s', iiotype[5]);

                fp = fopen(filename, 'rt' );

                if( fp==NULL )

                {

                        printf('open %s fail!\n', filename);

                        *fvoltage = 0.0;

                        ret = -1;

                        return ret;

                }

                fread( buf, 1, sizeof(buf), fp );

                fclose(fp);

                // convert to integer

                sscanf( buf, '%d', &value );

                *fvoltage = 0.8 * value;

                return ret;

        }

      

        int main(int argc, char** argv)

        {

                int ret = 0;

                float fvalue;

                printf('A5 IIO AD test v2.0\n');

                // read AIN1

                ret = read_AIN0(&fvalue);

                if(ret < 0)

                {

                        return ret;

                }

                printf('AIN1 = %.2f mV\n', fvalue);

                // read AIN2

                ret = read_AIN2(&fvalue);

                if(ret < 0)

                {

                        return ret;

                }

                printf('AIN2 = %.2f mV\n', fvalue);

 

                // read AIN3

                ret = read_AIN3(&fvalue);

                if(ret < 0)

                {

                        return ret;

                }

                printf('AIN3 = %.2f mV\n', fvalue);

 

                // read AIN4

                ret = read_AIN4(&fvalue);

                if(ret < 0)

                {

                        return ret;

                }

                printf('AIN4 = %.2f mV\n', fvalue);

 

                 // read AIN5

                ret = read_AIN5(&fvalue);

                if(ret < 0)

                {

                        return ret;

                }

                printf('AIN5 = %.2f mV\n', fvalue);

              

                return ret;

        }