你好，TI工程师！
我想在dm8168的mcasp0上注册一个声卡设备，MCA[0]_AHCLKR、MCA[0]_ACLKR、MCA[0]_AFSR、MCA[0]_AXR[0] 的输入源是在外部处理的数字信号，没有i2c控制， 这种情况能在8168上面注册一个可用的声卡设备吗?
下面的注册方法是需要：Machine、Platform和Codec三大部分
.name = "TLV320AIC3X",
.stream_name = "AIC3X",
.cpu_dai_name= "davinci-mcasp.2",
.codec_dai_name = "tlv320aic3x-hifi",
.codec_name = "tlv320aic3x-codec.1-0018",
.platform_name = "davinci-pcm-audio",
.init = ti81xx_evm_aic3x_init,
.ops = &ti81xx_evm_ops,
问题：
1、这种方法在8168是不是可行的；
2、如果可行，要怎么去修改，有没有相关芯片的案例
Hi Chris Meng，
谢谢你的回复，我采用了虚拟一个声卡的方法，但出现了snd_pcm_open出现了错误“cannot open audio device (Invalid argument)”，
代码修改如下：
Ti81xx-etv.c
static struct snd_soc_dai_link ti81xx_dummy_dai = {
.name = "DUMMY_SOC_LINK",
.stream_name = "dummy",
.cpu_dai_name = "davinci-mcasp.0",
.platform_name = "davinci-pcm-audio",
.codec_dai_name = "DUMMY-DAI-CODEC",
.codec_name = "dummy-dummy-codec",
};
-----
static struct snd_soc_card ti81xx_evm_snd_card2 = {
.name = "TI81XX ETV SOUND2",
.dai_link = &ti81xx_dummy_dai,
.num_links = 1,
};
static struct platform_device *ti81xx_pdev2;
------
ti81xx_pdev2 = platform_device_alloc("soc-audio", 2);
if (!ti81xx_pdev2) {
platform_device_put(ti81xx_pdev0);
platform_device_put(ti81xx_pdev1);
return -ENOMEM;
}
platform_set_drvdata(ti81xx_pdev2, &ti81xx_evm_snd_card2);
ret = platform_device_add(ti81xx_pdev2);
if (ret) {
printk(KERN_ERR "Can't add soc platform device\n");
platform_device_put(ti81xx_pdev0);
platform_device_put(ti81xx_pdev1);
platform_device_put(ti81xx_pdev2);
return ret;
}
static void __exit ti81xx_evm_soc_exit(void)
{
………….
platform_device_unregister(ti81xx_pdev2);
}
Board-ti8168etv.c
/* 这是配置mcasp 0 的多路复用 */
TI816X_MUX(MCA0_AXR0, OMAP_MUX_MODE1),
TI816X_MUX(MCA0_AXR1, OMAP_MUX_MODE1),
TI816X_MUX(MCA0_AXR2, OMAP_MUX_MODE1),
TI816X_MUX(MCA0_AXR3, OMAP_MUX_MODE0),
TI816X_MUX(MCA0_AXR4, OMAP_MUX_MODE0),
TI816X_MUX(MCA0_AXR5, OMAP_MUX_MODE0),
static u8 ti8168_iis_serializer_direction_0[] = {
RX_MODE, INACTIVE_MODE, INACTIVE_MODE,
INACTIVE_MODE, INACTIVE_MODE, INACTIVE_MODE, INACTIVE_MODE,
INACTIVE_MODE, INACTIVE_MODE, INACTIVE_MODE, INACTIVE_MODE,
INACTIVE_MODE, INACTIVE_MODE, INACTIVE_MODE, INACTIVE_MODE,
};
static struct snd_platform_data ti8168_evm_snd_data_0 = {
.tx_dma_offset = 0x46000000,
.rx_dma_offset = 0x46000000,
.op_mode = DAVINCI_MCASP_IIS_MODE,
.num_serializer = ARRAY_SIZE(ti8168_iis_serializer_direction_0),
.tdm_slots = 2,
.serial_dir = ti8168_iis_serializer_direction_0,
.asp_chan_q = EVENTQ_2,
.version = MCASP_VERSION_2,
.txnumevt = 0,
.rxnumevt = 1,
.clk_input_pin = MCASP_AHCLKX_OUT,
};
static struct platform_device ti8168_dummy_codec_device = {
.name = "dummy-dummy-codec",
.id = -1,
};
static struct platform_device *ti8168_devices[] __initdata = {
&ti8168_hdmi_audio_device,
&ti8168_hdmi_codec_device,
&ti8168_dummy_codec_device, //add
};
void __init ti8168_hdmi_mclk_init(void){don’t modify};
ti81xx_register_mcasp(0, &ti8168_evm_snd_data_0); //add
devices.c (mach-omap2)
static struct resource ti81xx_mcasp0_resource[] = {
{
.name = "mcasp0",
.start = TI81XX_ASP0_BASE,
.end = TI81XX_ASP0_BASE + (SZ_1K * 12) - 1,
.flags = IORESOURCE_MEM,
},
/* TX event */
{
.start = TI81XX_DMA_MCASP0_AXEVT,
.end = TI81XX_DMA_MCASP0_AXEVT,
.flags = IORESOURCE_DMA,
},
/* RX event */
{
.start = TI81XX_DMA_MCASP0_AREVT,
.end = TI81XX_DMA_MCASP0_AREVT,
.flags = IORESOURCE_DMA,
},
};
static struct platform_device ti81xx_mcasp0_device = {
.name = "davinci-mcasp", /* driver name */
.id = 0,
.num_resources = ARRAY_SIZE(ti81xx_mcasp0_resource),
.resource = ti81xx_mcasp0_resource,
};
void __init ti81xx_register_mcasp(int id, struct snd_platform_data *pdata)
{
ti81xx_mcasp0_device.dev.platform_data = pdata;
platform_device_register(&ti81xx_mcasp0_device);
}
CODEC
{
.name = "DUMMY-DAI-CODEC",
.capture = {
.stream_name = "capture",
.channels_min = 1,
.channels_max = 1,
.rates = SNDRV_PCM_RATE_48000
| SNDRV_PCM_RATE_32000
| SNDRV_PCM_RATE_44100
| SNDRV_PCM_RATE_96000
| SNDRV_PCM_RATE_192000 ,
.formats = SNDRV_PCM_FMTBIT_S16_LE
| SNDRV_PCM_FMTBIT_S32_LE
| SNDRV_PCM_FMTBIT_S20_3LE
| SNDRV_PCM_FMTBIT_S8
| SNDRV_PCM_FMTBIT_S24_LE,
},
},
我希望能得到你的帮助！
