Re: [PATCH v5 3/4] iio: adc: ad4691: add triggered buffer support

["Uwe Kleine-König" <ukleinek@kernel.org>]

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On Fri, Mar 27, 2026 at 01:07:59PM +0200, Radu Sabau via B4 Relay wrote:
> +static const char * const ad4691_gp_names[] = { "gp0", "gp1", "gp2", "gp3" };
> +
> +/*
> + * Valid ACC_DEPTH values where the effective divisor equals the count.
> + * From Table 13: ACC_DEPTH = 2^N yields right-shift = N, divisor = 2^N.
> + */
> +static const int ad4691_oversampling_ratios[] = { 1, 2, 4, 8, 16, 32 };
> [...]
> +static int ad4691_set_oversampling_ratio(struct iio_dev *indio_dev,
> +					 const struct iio_chan_spec *chan,
> +					 int osr)
> +{
> +	struct ad4691_state *st = iio_priv(indio_dev);
> +	unsigned int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(ad4691_oversampling_ratios); i++) {
> +		if (ad4691_oversampling_ratios[i] != osr)
> +			continue;

Given that ad4691_oversampling_ratios[i] is 1 << i; you can get rid of
the loop using something like:

	if (osr < 1 || osr > 32 || !is_power_of_2(osr))
		return -EINVAL;

	i = ilog2(osr);

> +
> +		IIO_DEV_ACQUIRE_DIRECT_MODE(indio_dev, claim);
> +		if (IIO_DEV_ACQUIRE_FAILED(claim))
> +			return -EBUSY;
> +
> +		st->osr[chan->scan_index] = osr;
> +		return regmap_write(st->regmap,
> +				    AD4691_ACC_DEPTH_IN(chan->scan_index), osr);
> +	}
> +
> +	return -EINVAL;
> +}

Best regards
Uwe

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