[alsa-devel] [PATCH] sound: soc: fsl: Do not set DAI sysclk when it is equal to system freq

[Łukasz Majewski]

Hi Nicolin,

> On Wed, Sep 06, 2017 at 08:35:50PM +0200, Łukasz Majewski wrote:
>   
>> 	clocks = <&clks IMX6QDL_CLK_SSI2_IPG>,
>> 		 <&clks IMX6QDL_CLK_SSI2>;
>> 	clock-names = "ipg", "baud";
> 
>>>>   			dailink_master: cpu {
>>>>   			    sound-dai = <&ssi2>;
>>>> 			    clock = <&SSSS>;
>>
>> 	If possible I do prefer a solution, which uses only DTS.
>> Side question - how to refer to baud clock from [1]?
> 
> Just add a property to this cpu node like:
> 	clock = <&clks IMX6QDL_CLK_SSI2>;

This doesn't solve the issue:

root at display5:~# speaker-test

speaker-test 1.1.3

Playback device is default
Stream parameters are 48000Hz, S16_LE, 1 channels
Using 16 octaves of pink noise
Rate set to 48000Hz (requested 48fsl-ssi-dai 202c000.ssi: bitclk > ipgclk/5
000Hz)
Buffer size range from 64fsl-ssi-dai 202c000.ssi: ASoC: can't set 
202c000.ssi hw params: -22
  to 65536
Period size range from 32 to 8191
Using max buffer size 65536
Periods = 4
Unable to set hw params for playback: Invalid argument
Setting of hwparams failed: Invalid argument


> 
>>>> 			    system-clock-frequency = <XXXX>;
> 
> This would not be necessary unless you want to specify a clock rate
> so as to override the clock rate configuration in hw_params().
> 
>>> This is the right solution based on current simple-card driver. For
>>> SSI (having two clocks), you have to specify the baud clock in the
>>> cpu node like that. I believe this is what the simple-card designer
>>> expected users to do since the cpu node is the first place that the
>>> driver tries to look at.
>>
>> I will give a shoot the option with adding the ipg clock.
> 
> No, not ipg clock. You should use the second clock -- baud clock.
> 


-- 
Best regards,

Lukasz Majewski

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