[PATCH 4.16 25/47] iio: ad7793: implement IIO_CHAN_INFO_SAMP_FREQ

From: Greg Kroah-Hartman
Date: Mon Jun 04 2018 - 03:06:31 EST


4.16-stable review patch. If anyone has any objections, please let me know.

------------------

From: Michael Nosthoff <committed@xxxxxxxx>

commit 490fba90a90eb7b741f57fefd2bcf2c1e11eb471 upstream.

This commit is a follow-up to changes made to ad_sigma_delta.h
in staging: iio: ad7192: implement IIO_CHAN_INFO_SAMP_FREQ
which broke ad7793 as it was not altered to match those changes.

This driver predates the availability of IIO_CHAN_INFO_SAMP_FREQ
attribute wherein usage has some advantages like it can be accessed by
in-kernel consumers as well as reduces the code size.

Therefore, use IIO_CHAN_INFO_SAMP_FREQ to implement the
sampling_frequency attribute instead of using IIO_DEV_ATTR_SAMP_FREQ()
macro.

Move code from the functions associated with IIO_DEV_ATTR_SAMP_FREQ()
into respective read and write hooks with the mask set to
IIO_CHAN_INFO_SAMP_FREQ.

Fixes: a13e831fcaa7 ("staging: iio: ad7192: implement IIO_CHAN_INFO_SAMP_FREQ")

Signed-off-by: Michael Nosthoff <committed@xxxxxxxx>
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/iio/adc/ad7793.c | 75 +++++++++++++++--------------------------------
1 file changed, 24 insertions(+), 51 deletions(-)

--- a/drivers/iio/adc/ad7793.c
+++ b/drivers/iio/adc/ad7793.c
@@ -348,55 +348,6 @@ static const u16 ad7793_sample_freq_avai
static const u16 ad7797_sample_freq_avail[16] = {0, 0, 0, 123, 62, 50, 0,
33, 0, 17, 16, 12, 10, 8, 6, 4};

-static ssize_t ad7793_read_frequency(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- struct ad7793_state *st = iio_priv(indio_dev);
-
- return sprintf(buf, "%d\n",
- st->chip_info->sample_freq_avail[AD7793_MODE_RATE(st->mode)]);
-}
-
-static ssize_t ad7793_write_frequency(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
-{
- struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- struct ad7793_state *st = iio_priv(indio_dev);
- long lval;
- int i, ret;
-
- ret = kstrtol(buf, 10, &lval);
- if (ret)
- return ret;
-
- if (lval == 0)
- return -EINVAL;
-
- for (i = 0; i < 16; i++)
- if (lval == st->chip_info->sample_freq_avail[i])
- break;
- if (i == 16)
- return -EINVAL;
-
- ret = iio_device_claim_direct_mode(indio_dev);
- if (ret)
- return ret;
- st->mode &= ~AD7793_MODE_RATE(-1);
- st->mode |= AD7793_MODE_RATE(i);
- ad_sd_write_reg(&st->sd, AD7793_REG_MODE, sizeof(st->mode), st->mode);
- iio_device_release_direct_mode(indio_dev);
-
- return len;
-}
-
-static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
- ad7793_read_frequency,
- ad7793_write_frequency);
-
static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
"470 242 123 62 50 39 33 19 17 16 12 10 8 6 4");

@@ -424,7 +375,6 @@ static IIO_DEVICE_ATTR_NAMED(in_m_in_sca
ad7793_show_scale_available, NULL, 0);

static struct attribute *ad7793_attributes[] = {
- &iio_dev_attr_sampling_frequency.dev_attr.attr,
&iio_const_attr_sampling_frequency_available.dev_attr.attr,
&iio_dev_attr_in_m_in_scale_available.dev_attr.attr,
NULL
@@ -435,7 +385,6 @@ static const struct attribute_group ad77
};

static struct attribute *ad7797_attributes[] = {
- &iio_dev_attr_sampling_frequency.dev_attr.attr,
&iio_const_attr_sampling_frequency_available_ad7797.dev_attr.attr,
NULL
};
@@ -505,6 +454,10 @@ static int ad7793_read_raw(struct iio_de
*val -= offset;
}
return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *val = st->chip_info
+ ->sample_freq_avail[AD7793_MODE_RATE(st->mode)];
+ return IIO_VAL_INT;
}
return -EINVAL;
}
@@ -542,6 +495,26 @@ static int ad7793_write_raw(struct iio_d
break;
}
break;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ if (!val) {
+ ret = -EINVAL;
+ break;
+ }
+
+ for (i = 0; i < 16; i++)
+ if (val == st->chip_info->sample_freq_avail[i])
+ break;
+
+ if (i == 16) {
+ ret = -EINVAL;
+ break;
+ }
+
+ st->mode &= ~AD7793_MODE_RATE(-1);
+ st->mode |= AD7793_MODE_RATE(i);
+ ad_sd_write_reg(&st->sd, AD7793_REG_MODE, sizeof(st->mode),
+ st->mode);
+ break;
default:
ret = -EINVAL;
}