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Subject: Re: [PATCH] clk: fractional-divider: Improve approximation when zero based
From:   Stephen Boyd <sboyd@kernel.org>
Cc:     Frank Oltmanns <frank@oltmanns.dev>,
        Abel Vesa <abelvesa@kernel.org>, Peng Fan <peng.fan@nxp.com>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        Jacky Bai <ping.bai@nxp.com>,
        Anson Huang <Anson.Huang@nxp.com>, linux-clk@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
To:     Frank Oltmanns <frank@oltmanns.dev>,
        Michael Turquette <mturquette@baylibre.com>
Date:   Mon, 12 Jun 2023 14:39:00 -0700
User-Agent: alot/0.10
Precedence: bulk

Quoting Frank Oltmanns (2023-05-29 06:34:33)
> Consider the CLK_FRAC_DIVIDER_ZERO_BASED flag when finding the best
> approximation for m and n. By doing so, increase the range of valid
> values for the numerator and denominator by 1.
>=20
> Cc: A.s. Dong <aisheng.dong@nxp.com
> Signed-off-by: Frank Oltmanns <frank@oltmanns.dev>
> ---
> I stumpled upon this, when familiarizing myself with clk drivers. Unfortu=
nately,
> I have no boards to test this patch. It seems the only user of this flag =
in
> mainline is drivers/clk/imx/clk-composite-7ulp.c, therefore I'm cc-ing
> get_maintainers.pl --git-blame -f drivers/clk/imx/clk-composite-7ulp.c
> in the hopes of a wider audience.
>=20
> Thank you for considering this contribution,

Thanks for looking at this. Can you add a kunit test (or a suite of
tests) to confirm that this doesn't break existing functionality and
also improves a case that would have failed or been suboptimal before?