[PATCH] ALSA: hda: Refactor Intel NHLT init

[Pierre-Louis Bossart]

On 4/23/20 6:40 AM, Cezary Rojewski wrote:
> On 2020-04-23 13:24, Takashi Iwai wrote:
>> On Thu, 23 Apr 2020 13:21:36 +0200,
>> Cezary Rojewski wrote:
>>>
>>> NHLT fetch based on _DSM prevents ACPI table override mechanism from
>>> being utilized. Make use of acpi_get_table to enable it and get rid of
>>> redundant code.
>>>
>>> Signed-off-by: Cezary Rojewski <cezary.rojewski at intel.com>
>>
>> This looks like a nice cleanup and I'll happily apply if anyone can
>> test with the actual hardware -- currently mine has no DSP, so unable
>> to check.
>>
>>
>> thanks,
>>
>> Takashi
>>
> 
> NHLT override method has been added for internal use half a year ago and 
> is for some time the default method within our CI. This is tested on a 
> wide spread of hardware, that is any Intel AVS archtecture, including 
> production laptops.

We are checking independently with SOF CI [1], the NHLT is used to 
detect microphone counts so we'll see if there's a regression.

That said, for my education Cezary an you clarify what you typically 
override? the settings are usually tied to specific hardware configs.
Also the NHLT may point to a topology file name but with your recent 
changes an alternate file can be used, so it's not clear to me how 
non-Intel folks might use the override and for what?

While I am at it, we recently had a bug report where a user provided the 
NHLT, and I had no idea how to go about parsing it to check its 
contents. Are there any tools to dump the contents in human-readable 
representation?

[1] https://github.com/thesofproject/linux/pull/2046