TQ2440之kernel---i2s驱动分析1测试

测试demo

#include "stdio.h"
#include "stdlib.h"
#include "unistd.h"
#include "fcntl.h"
#include "sys/types.h"
#include "sys/ioctl.h"
#include "linux/soundcard.h"
#include "termios.h"

#define RATE 8000
#define CHANNELS 1
#define BITS 16
#define SIZE 320

unsigned char buf[SIZE];

int main(int argc,char **argv)
{
    int dspw, mixfd;
    int arg;
    FILE *outfd;
    char *name;
    int vol;
    int i;

    if(argc!=2)
    {
        printf("usage:  %s file_name\n",argv[0]);
        return 0;
    }
    name=argv[1];

    //ioctl mixer to set volume
    mixfd = open("/dev/mixer",O_RDWR);
    if(mixfd < 0)
    {
        perror("open /dev/mixer Read&&Write error\n");
        return 1;
    }

#if 1
    ioctl(mixfd, SOUND_MIXER_READ_VOLUME, &vol);
    printf("read vol=0x%x\n", vol);

    vol = 0x3030;
    ioctl(mixfd, SOUND_MIXER_WRITE_VOLUME, &vol);

    ioctl(mixfd, SOUND_MIXER_READ_VOLUME, &vol);
    printf("read vol=0x%x\n", vol);
#endif


#if 0
    //printf("SOUND_MIXER_NRDEVICES=%d\n", SOUND_MIXER_NRDEVICES);
    for (i = 0; i < SOUND_MIXER_NRDEVICES/8; i++)
    {
        ioctl(mixfd, MIXER_READ(i), &vol);
        printf("[%d]:vol=0x%x\n", i, vol);

        vol = 0x3030;
        ioctl(mixfd, MIXER_WRITE(i), &vol);

        ioctl(mixfd, MIXER_READ(i), &vol);
        printf("[%d]:vol=0x%x\n", i, vol);
    }
#endif

    //write only /dev/dsp
    dspw=open("/dev/dsp",O_WRONLY);
    if(dspw<0)
    {
        perror("open /dev/dsp writeonly error\n");
        return 1;
    }
    arg=BITS;
    if(ioctl(dspw,SOUND_PCM_WRITE_BITS,&arg)==-1)
    {
        perror("set writeonly /dev/dsp bits error\n");
        return 1;
    }
    arg=RATE;
    if(ioctl(dspw,SOUND_PCM_WRITE_RATE,&arg)==-1)
    {
        perror("set writeonly /dev/dsp rate error\n");
        return 1;
    }
    arg=CHANNELS;
    if(ioctl(dspw,SOUND_PCM_WRITE_CHANNELS,&arg)==-1)
    {
        perror("set writeonly /dev/dsp channels error\n");
        return 1;
    }

    //outfile open
    outfd=fopen(name,"r");
    if(outfd==NULL)
    {
        printf("open %s error\n",argv[1]);
        return 1;
    }

    while(!feof(outfd))
    {
        fread(buf,1,sizeof(buf),outfd);
        write(dspw,buf,sizeof(buf));
    }

    close(dspw);
    fclose(outfd);
    return 0;
}

打开/dev/mixer,利用ioctl设置音量0x3030(左右)
打开/dev/dsp, 输入音频数据，进行播放

Makefile:

GCC=/work/tq/bak/toolchain/4.3.3/bin/arm-linux-gcc
play:play.c
    ${GCC} -g -o $@ $<
    cp ./play /tmp/

letitgo_16K_16bit_single.wav     --> 采样级别:16KHz,采样大小:16Bit,频道:单声道,位速:256kbps
letitgo_16K_16bit_stereo.wav    --> 采样级别:16KHz,采样大小:16Bit,频道:立体道,位速:512kbps
letitgo_8K_16bit_sigle.wav        --> 采样级别:8KHz,采样大小:16Bit,频道:单声道,位速:128kbps
letitgo_8K_16bit_stereo.wav     --> 采样级别:8KHz,采样大小:16Bit,频道:立体道,位速:256kbps

测试结果:
    letitgo_16K_16bit_single.wav --> 正常播放
    letitgo_16K_16bit_stereo.wav --> 播放慢
    letitgo_8K_16bit_sigle.wav    --> 播放快
    letitgo_8K_16bit_stereo.wav --> 正常播放