linux-kernel - Re: [PATCH 2/7] ASoC: codecs: lpass-wsa-macro: fix compander volume hack

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Message-ID: <ZaeZBjKezfdslS2L@hovoldconsulting.com>
Date: Wed, 17 Jan 2024 10:08:22 +0100
From: Johan Hovold <johan@...nel.org>
To: Srinivas Kandagatla <srinivas.kandagatla@...aro.org>
Cc: Johan Hovold <johan+linaro@...nel.org>, Mark Brown <broonie@...nel.org>,
	Banajit Goswami <bgoswami@...cinc.com>,
	Liam Girdwood <lgirdwood@...il.com>,
	Jaroslav Kysela <perex@...ex.cz>, Takashi Iwai <tiwai@...e.com>,
	alsa-devel@...a-project.org, linux-sound@...r.kernel.org,
	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Subject: Re: [PATCH 2/7] ASoC: codecs: lpass-wsa-macro: fix compander volume
 hack

On Tue, Jan 16, 2024 at 02:10:19PM +0100, Johan Hovold wrote:
> On Tue, Jan 16, 2024 at 11:10:21AM +0000, Srinivas Kandagatla wrote:

> > This is not a hack, wsa codec requires gain to be programmed after the 
> > clk is enabled for that particular interpolator.
> 
> Ok, but then it's also broken as, as I mentioned off-list, these
> registers are cached so unless companding is enabled, the write on
> enable will have no effect.

I was obviously confused here, and indeed tests reveal that those writes
are needed for any prior updates to take effect (e.g. volume changes
while the codec is runtime suspended).

I've just sent a v2 here:

	https://lore.kernel.org/lkml/20240117090331.31111-1-johan+linaro@kernel.org/

Johan