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Subject: Re: [PATCH] clk: sunxi-ng: v3s: add support for variable rate audio
 pll output
To:     Maxime Ripard <maxime@cerno.tech>,
        Tobias Schramm <t.schramm@manjaro.org>
Cc:     Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Icenowy Zheng <icenowy@aosc.io>, Chen-Yu Tsai <wens@csie.org>,
        Jernej Skrabec <jernej.skrabec@siol.net>,
        linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
References: <20210212135725.283877-1-t.schramm@manjaro.org>
 <20210218075835.o43tyarpimrcwbvk@gilmour>
From:   Tobias Schramm <t.schramm@manjaro.org>
Message-ID: <7379a9c3-3578-5cf1-53ed-ace8ff68434b@manjaro.org>
Date:   Thu, 18 Feb 2021 09:51:54 +0100
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Hi Maxime,
> 
> It's not really clear to me how that would help.
> 
> The closest frequency we can provide for 24.576MHz would be 24580645 Hz,
> with N = 127, M = 31 and P = 4, so it would work with what we have
> already?
> 

As far as I'm aware the multiplier N ranges from 0 to 128 (offset of 1 
from 0 to 127). Thus 24MHz * 128 / 25 / 5 = 24.576MHz. Since this 
requires the postdiv to be set to 5 it is not supported yet.

Cheers,
Tobias