[External] Re: [PATCH] ALSA: hda/realtek: Add quirk for Lenovo Ideapad S740

[Mark Pearson]

On 16/04/2021 12:05, Pierre-Louis Bossart wrote:
> 
> 
> On 4/16/21 3:47 AM, Jaroslav Kysela wrote:
>> Dne 16. 04. 21 v 10:12 Takashi Iwai napsal(a):
>>> Lenovo Ideapad S740 requires quite a few COEF setups to make its
>>> speakers working.  The verb table was provided from Ryan Prescott as
>>> the result of investigation via qemu:
>>>   
>>> https://github.com/ryanprescott/realtek-verb-tools/wiki/How-to-sniff-verbs-from-a-Windows-sound-driver
>>>
>>
>> [Cc: to Kailang / Realtek]
>>
>> I believe that this sequence contains I2C writes to amplifier chips.
>> It would
>> be really helpful, if Realtek can provide more information for the I2C
>> master
>> interface for their codecs (describe basic I2C I/O).
> 
> The biggest problem is to figure what address/value pairs to write with
> I2C into the amplifiers, and here the catch is that those I2C/I2S
> amplifiers may or may not be sourced from Realtek, and it'd be difficult
> for Realtek to provide documentation on their competition, wouldn't it?

Is this something, at least for our platforms, that we (Lenovo) should
be able to give guidance on more easily, perhaps working with the HW vendor?

I know I've had limited joy here previously on our non-Linux certified
platforms, but the more concise and targeted I make the request to the
HW/FW team the more likely I am to get success. Nothing is guaranteed
and if I go in with "audio doesn't work" they'll ignore me, but if I'm
asking for some specific information (which isn't proprietary) I'm more
likely to succeed, especially if it's details that they likely already
have documented. I'm definitely happy to at least try and do that - but
I've had trouble thus far knowing how to frame that request to get the
details needed.

It's been brilliant watching the debug of the S740 and I really want to
take advantage of this work to help out on our systems where we've been
stuck before.

As an aside (and probably this should be a different thread) if anybody
in the audio community would be interested in doing a training session
for the Lenovo Linux team so we can better understand how to make audio
better and contribute let me know. It's such a complicated subsystem and
knowing how everything hooks together, and what needs to be done where,
is something I haven't figured out yet. I believe we'd pay for your time
if that's required - I just need an expert who has the time and interest
to run a session :) The aim would be to get to the stage where we can
contribute and make audio better on our platforms generally - so it
would hopefully be a win-win. If that hit's anybodies interest let me know.

Mark