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: a13e831fca ("staging: iio: ad7192: implement
IIO_CHAN_INFO_SAMP_FREQ")

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Alexandru Ardelean 2018-03-12 14:06:54 +02:00 committed by Jonathan Cameron
parent 7eb6b35d93
commit 381522c030
1 changed files with 56 additions and 0 deletions

View File

@ -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,
};