Re: [RFC PATCH v3 6/9] power: supply: Add batinfo functions for OCV to SOC with 0.1% accuracy

From: Linus Walleij <linus.walleij@linaro.org>
To: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Cc: Matti Vaittinen <mazziesaccount@gmail.com>,
	Sebastian Reichel <sre@kernel.org>,
	Rob Herring <robh+dt@kernel.org>,
	Lee Jones <lee.jones@linaro.org>,
	rostokus@gmail.com, fan.chen@mediatek.com,
	linux-pm@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-power@fi.rohmeurope.com
Subject: Re: [RFC PATCH v3 6/9] power: supply: Add batinfo functions for OCV to SOC with 0.1% accuracy
Date: Fri, 19 Nov 2021 02:49:15 +0100	[thread overview]
Message-ID: <CACRpkdZ4HvgYyssNw_bfWR-7YQXEe_nPOtZChY_ZPUpz_Ga7jA@mail.gmail.com> (raw)
In-Reply-To: <392c7aa891d466bc4df06a076090150319e0e7dc.1637061794.git.matti.vaittinen@fi.rohmeurope.com>

On Tue, Nov 16, 2021 at 1:27 PM Matti Vaittinen
<matti.vaittinen@fi.rohmeurope.com> wrote:

> The battery info functions computing the state-of-charge (SOC) based
> on open-circuit-voltage (OCV) are returning SOC using units of 1%.
>
> Some capacity estimation computations require higher accuracy. Add
> functions that return SOC using units of 0.1% to reduce rounding error.
>
> Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>

That sounds useful.

> +int power_supply_ocv2dcap_simple(struct power_supply_battery_ocv_table *table,
> +                               int table_len, int ocv)
> +{
> +       int i, cap, tmp;

Why a whole new function? Just rename the original power_supply_ocv2cap_simple()
to power_supply_ocv2dcap_simple and patch it to return the finegrained value,
then add a wrapper that use that function but drops it down by one order
of magnitude.

> +int power_supply_batinfo_ocv2dcap(struct power_supply_battery_info *info,
> +                                 int ocv, int temp)

Same with this, saves a lot of code!

(Also will use my new interpolation routines since you refactor
on top of that.)

Yours,
Linus Walleij