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Date: Mon, 10 Jun 2024 10:26:29 -0300
From: =?utf-8?Q?Jo=C3=A3o_Paulo_Gon=C3=A7alves?= <jpaulo.silvagoncalves@gmail.com>
To: Jonathan Cameron <jic23@kernel.org>
Cc: Francesco Dolcini <francesco@dolcini.it>,
	Lars-Peter Clausen <lars@metafoo.de>,
	Liam Girdwood <lgirdwood@gmail.com>,
	Mark Brown <broonie@kernel.org>,
	=?utf-8?Q?Jo=C3=A3o_Paulo_Gon=C3=A7alves?= <joao.goncalves@toradex.com>,
	linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org,
	Francesco Dolcini <francesco.dolcini@toradex.com>
Subject: Re: [PATCH v2 2/2] iio: adc: ti-ads1119: Add driver
Message-ID: <20240610132629.xjj32vzrekpl356w@joaog-nb>
References: <20240606163529.87528-1-francesco@dolcini.it>
 <20240606163529.87528-3-francesco@dolcini.it>
 <20240609115234.20e08840@jic23-huawei>
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In-Reply-To: <20240609115234.20e08840@jic23-huawei>

Hi Jonathan,

Thanks for the review!

> > +
> > +static int ads1119_validate_gain(struct ads1119_state *st, int scale, int uscale)
> > +{
> > +	int gain = 1000000 / ((scale * 1000000) + uscale);
> > +
> > +	switch (gain) {
> > +	case 1:
> > +	case 4:
> > +		return gain;
> Odd to calculate it if we don't need it
> 		return MICRO / (scale * MICRO + uscale);
> use constants as it's easy to drop a 0 in these without anyone noticing.
>
> > +	default:
> > +		return -EINVAL;
> > +	}
> > +}
> > +

Just a minor. I do use the calculated value on write_raw() by storing it as the
new channel gain and would still need to validate it as scale/uscale comes from
userspace. Maybe I can just remove the validate_gain function and do the check
directly on write_raw(). What do you think?

Regards,
João Paulo Gonçalves