Commit 381522c0 authored by Alexandru Ardelean's avatar Alexandru Ardelean Committed by Jonathan Cameron
Browse files

iio: adc: ad7791: implement IIO_CHAN_INFO_SAMP_FREQ 



Now that the old read/write frequency sysfs attrs have been removed, we
have a clean slate to implement IIO_CHAN_INFO_SAMP_FREQ.

This driver also pre-dates IIO_CHAN_INFO_SAMP_FREQ, and this change
implements this behavior.

The `ad7791_write_raw` would have overlapped quite a bit with the old
read/write frequency functions, making things a bit harder to follow.

Fixes: a13e831f ("staging: iio: ad7192: implement
IIO_CHAN_INFO_SAMP_FREQ")

Signed-off-by: default avatarAlexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent 7eb6b35d

drivers/iio/adc/ad7791.c

+56 −0
Original line number Diff line number Diff line
@@ -153,6 +153,17 @@ struct ad7791_state { 
	const struct ad7791_chip_info *info;

};



static const int ad7791_sample_freq_avail[8][2] = {

	[AD7791_FILTER_RATE_120] =  { 120, 0 },

	[AD7791_FILTER_RATE_100] =  { 100, 0 },

	[AD7791_FILTER_RATE_33_3] = { 33,  300000 },

	[AD7791_FILTER_RATE_20] =   { 20,  0 },

	[AD7791_FILTER_RATE_16_6] = { 16,  600000 },

	[AD7791_FILTER_RATE_16_7] = { 16,  700000 },

	[AD7791_FILTER_RATE_13_3] = { 13,  300000 },

	[AD7791_FILTER_RATE_9_5] =  { 9,   500000 },

};



static struct ad7791_state *ad_sigma_delta_to_ad7791(struct ad_sigma_delta *sd)

{

	return container_of(sd, struct ad7791_state, sd);
@@ -202,6 +213,7 @@ static int ad7791_read_raw(struct iio_dev *indio_dev, 
{

	struct ad7791_state *st = iio_priv(indio_dev);

	bool unipolar = !!(st->mode & AD7791_MODE_UNIPOLAR);

	unsigned int rate;



	switch (info) {

	case IIO_CHAN_INFO_RAW:
@@ -239,11 +251,53 @@ static int ad7791_read_raw(struct iio_dev *indio_dev, 
			*val2 = chan->scan_type.realbits - 1;



		return IIO_VAL_FRACTIONAL_LOG2;

	case IIO_CHAN_INFO_SAMP_FREQ:

		rate = st->filter & AD7791_FILTER_RATE_MASK;

		*val = ad7791_sample_freq_avail[rate][0];

		*val2 = ad7791_sample_freq_avail[rate][1];

		return IIO_VAL_INT_PLUS_MICRO;

	}



	return -EINVAL;

}



static int ad7791_write_raw(struct iio_dev *indio_dev,

	struct iio_chan_spec const *chan, int val, int val2, long mask)

{

	struct ad7791_state *st = iio_priv(indio_dev);

	int ret, i;



	ret = iio_device_claim_direct_mode(indio_dev);

	if (ret)

		return ret;



	switch (mask) {

	case IIO_CHAN_INFO_SAMP_FREQ:

		for (i = 0; i < ARRAY_SIZE(ad7791_sample_freq_avail); i++) {

			if (ad7791_sample_freq_avail[i][0] == val &&

			    ad7791_sample_freq_avail[i][1] == val2)

				break;

		}



		if (i == ARRAY_SIZE(ad7791_sample_freq_avail)) {

			ret = -EINVAL;

			break;

		}



		st->filter &= ~AD7791_FILTER_RATE_MASK;

		st->filter |= i;

		ad_sd_write_reg(&st->sd, AD7791_REG_FILTER,

				sizeof(st->filter),

				st->filter);

		break;

	default:

		ret = -EINVAL;

	}



	iio_device_release_direct_mode(indio_dev);

	return ret;

}



static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("120 100 33.3 20 16.7 16.6 13.3 9.5");



static struct attribute *ad7791_attributes[] = {
@@ -257,12 +311,14 @@ static const struct attribute_group ad7791_attribute_group = { 


static const struct iio_info ad7791_info = {

	.read_raw = &ad7791_read_raw,

	.write_raw = &ad7791_write_raw,

	.attrs = &ad7791_attribute_group,

	.validate_trigger = ad_sd_validate_trigger,

};



static const struct iio_info ad7791_no_filter_info = {

	.read_raw = &ad7791_read_raw,

	.write_raw = &ad7791_write_raw,

	.validate_trigger = ad_sd_validate_trigger,

};