现在用的是 SDK7.0
dts : am335x-boneblack.dts
现在 hdmi 口有视频输出，启动的时候可以看到。
但如果要使用 hdmi 音频驱动应该要怎么做？
在内核配置里我的配置选了：
<*> Sound card support --->
<*> Advanced Linux Sound Architecture --->
--- Advanced Linux Sound Architecture │ │
│ │ < > Sequencer support │ │
│ │ <M> OSS Mixer API │ │
│ │ <M> OSS PCM (digital audio) API │ │
│ │ [*] OSS PCM (digital audio) API - Include plugin system │ │
│ │ < > HR-timer backend support │ │
│ │ [ ] Dynamic device file minor numbers │ │
│ │ [*] Support old ALSA API │ │
│ │ [*] Verbose procfs contents │ │
│ │ [*] Verbose printk │ │
│ │ [*] Debug │ │
│ │ [ ] More verbose debug │ │
│ │ [ ] Enable PCM ring buffer overrun/underrun debugging │ │
│ │ [*] Generic sound devices ---> │ │
│ │ [*] PCI sound devices ---> │ │
│ │ [*] ARM sound devices ---- │ │
│ │ [*] SPI sound devices ---- │ │
│ │ [*] USB sound devices ---> │ │
│ │ <*> ALSA for SoC audio support ---> │ │
│ │
--- ALSA for SoC audio support │ │
│ │ < > SoC Audio for the Atmel System-on-Chip │ │
│ │ <*> SoC Audio for TI DAVINCI or AM33XX/AM43XX chips │ │
│ │ <*> SoC Audio for the AM33XX chip based boards │ │
│ │ <M> SoC Audio for the AM43XX and TLV320AIC3111 based board │ │
│ │ <M> Synopsys I2S Device Driver │ │
│ │ <*> SoC Audio for the Texas Instruments OMAP chips │ │
│ │ < > SoC Audio support for Nokia N810 │ │
│ │ < > SoC Audio support for Nokia RX-51 │ │
│ │ < > SoC Audio support for OMAP3517 / AM3517 EVM │ │
│ │ <M> SoC Audio support for DRA7 EVM │ │
│ │ <M> SoC Audio support for TI SoC based boards with twl4030 codec │ │
│ │ <M> SoC Audio support for OMAP boards using ABE and twl6040 codec │ │
│ │ <*> SoC Audio support for Texas Instruments OMAP HDMI │ │
│ │ <M> SoC Audio support for OMAP3 Pandora │ │
│ │ <*> ASoC Simple sound card support
但系统加载后 没有 相关 alsa 声卡，
还要做 Device tree?
