[alsa-devel] Audio play problem with tlv320aic3106 in mainline.

[Peter Ujfalusi]

On 05/28/2015 02:36 PM, Enric Balletbo Serra wrote:
> Dear all,
> 
> Recently I sent some patches to add support for a new board based on
> AM335x processor [1]. The board has the TLV320AIC3106 audio codec, the
> MCLK signal is provided by an external oscillator of 12MHz. The
> problem is that when I play a wav file for example I heard the song a
> double speed. This is with v4.0 and current mainline.
> 
> In dts file I defined "ti,codec-clock-rate = <12000000>;" which is the
> correct value. Curiously when I changed the clock rate value to
> 24000000 I heard the song at normal speed. AFAIK the correct value for
> clock-rate is 12MHz so I suspect that something is wrong in the
> driver, maybe it sets a wrong clock divider/multiplier ? Anyone can
> point me in the right direction to fix the issue ? I see that
> am335x-evm and am335x-pepper boards also uses this audio codec, did
> anyone with those boards have the same problem?

It might be really 24MHz.
If the MCLK in your board is wired like am335x-evmsk or how BeagleBone's audio
capes are wired (MCLK is coming from AM335x's EVENT_INTR0/1 pin as CLKOUT1/2)
then 24MHz is correct. On the am335x-evm there is a dedicated crystal
providing the 12MHz.

> 
> [1] https://patchwork.kernel.org/patch/6480071/
> 
> Thanks in advance,
> Enric
> 

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