Re: [PATCH v2 43/65] ASoC: tlv320aic32x4: Add a determine_rate hook

From: Maxime Ripard <maxime@cerno.tech>
To: Mark Brown <broonie@kernel.org>
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Subject: Re: [PATCH v2 43/65] ASoC: tlv320aic32x4: Add a determine_rate hook
Date: Mon, 7 Nov 2022 09:43:22 +0100	[thread overview]
Message-ID: <20221107084322.gk4j75r52zo5k7xk@houat> (raw)
In-Reply-To: <Y2U2+ePwRieYkNjv@sirena.org.uk>

Hi Mark,

On Fri, Nov 04, 2022 at 03:59:53PM +0000, Mark Brown wrote:
> On Fri, Nov 04, 2022 at 04:51:23PM +0100, Maxime Ripard wrote:
> 
> > Just filling determine_rate if it's missing with
> > __clk_mux_determine_rate will possibly pick different parents, and I'm
> > fairly certain that this have never been tested on most platforms, and
> > will be completely broken. And I don't really want to play a game of
> > whack-a-mole adding that flag everywhere it turns out it's broken.
> 
> Well, hopefully everyone for whom it's an issue currently will be
> objecting to this version of the change anyway so we'll either know
> where to set the flag or we'll get the whack-a-mole with the series
> being merged?

I'm sorry, I'm not sure what you mean here. The only issue to fix at the
moment is that determine_rate and set_parent aren't coupled, and it led
to issues due to oversight.

I initially added a warning but Stephen wanted to fix all users in that
case and make that an error instead.

If I filled __clk_mux_determine_rate into clocks that weren't using it
before, I would change their behavior. With that flag set, on all users
I add __clk_mux_determine_rate to, the behavior is the same than what we
previously had, so the risk of regressions is minimal, and everything
should keep going like it was?

Maxime