[PATCH 3/4] ASoC: Intel: bdw-rt5677: Remove ignore_suspend flag from SSP0 dai link

[Pierre-Louis Bossart]

On 3/31/20 7:12 AM, Hans de Goede wrote:
> Hi,
> 
> On 3/31/20 12:54 PM, Pierre-Louis Bossart wrote:
>>
>>> Don't believe WoV for WPT has been added for SST linux so 
>>> .ignore_suspend=1 achieves nothing. The offload part is probably just 
>>> limited to bigger buffer size compared to system pin than anything 
>>> else. So, nothing prevents from removing .ignore_suspend for SST 
>>> solutions until WoV is verified. Don't know about SOF side.
>>> Pierre, what's your take on this?
>>
>> I think on Baytrail and Broadwell we will most likely never enable 
>> hotwording on the Intel DSP, and S0i1-Playback isn't planned either.
>>
>> However hotwording is enabled on the RT5677 and there may be clocking 
>> dependencies so that the RT5677 remains operational - at least the 
>> mclk needs to be on, so the bdw-rt5677 case probably needs more work.
>>
>> While I am at it, I think the notion of .ignore_suspend has an 
>> assumption baked in. It will work if the only suspend mode is S0i1. If 
>> the platform can choose between S0i1 and S3, then we would still want 
>> to suspend all paths in S3, which currently isn't really possible.
> 
> You can check if S0i1 will be used by using:
> 
> pm_suspend_default_s2idle()
> 
> If this returns true then S0i1 will be used, otherwise S3.
> 
> This is defined in kernel/power/suspend.c and always build, so it
> should be ok to also use this in non x86 specific code-paths
> (it will simply always return false there I believe).

Yes, but what I meant is that when the target is S3, we have no way of 
disabling those .ignore_suspend that were added for S0i1 usages.