staging: iio: ad7606: implement IIO_CHAN_INFO_OVERSAMPLING_RATIO

This driver predates the availability of IIO_CHAN_INFO_OVERSAMPLING_RATIO
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_OVERSAMPLING_RATIO to implement the
oversampling_ratio attribute instead of using IIO_DEVICE_ATTR() macro.

Move code from the functions associated with IIO_DEVICE_ATTR() into
the read_raw hook as well as add the write_raw hook with both masks set
to IIO_CHAN_INFO_OVERSAMPLING_RATIO.

Signed-off-by: Eva Rachel Retuya <eraretuya@gmail.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/staging/iio/adc/ad7606_core.c b/drivers/staging/iio/adc/ad7606_core.c
index cbd6bc5..2042225 100644 (file)
--- a/drivers/staging/iio/adc/ad7606_core.c
+++ b/drivers/staging/iio/adc/ad7606_core.c
@@ -103,6 +103,9 @@ static int ad7606_read_raw(struct iio_dev *indio_dev,
                *val = st->range * 2;
                *val2 = st->chip_info->channels[0].scan_type.realbits;
                return IIO_VAL_FRACTIONAL_LOG2;
+       case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+               *val = st->oversampling;
+               return IIO_VAL_INT;
        }
        return -EINVAL;
 }
@@ -145,16 +148,6 @@ static IIO_DEVICE_ATTR(in_voltage_range, S_IRUGO | S_IWUSR,
                       ad7606_show_range, ad7606_store_range, 0);
 static IIO_CONST_ATTR(in_voltage_range_available, "5000 10000");
 
-static ssize_t ad7606_show_oversampling_ratio(struct device *dev,
-                                             struct device_attribute *attr,
-                                             char *buf)
-{
-       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-       struct ad7606_state *st = iio_priv(indio_dev);
-
-       return sprintf(buf, "%u\n", st->oversampling);
-}
-
 static int ad7606_oversampling_get_index(unsigned int val)
 {
        unsigned char supported[] = {0, 2, 4, 8, 16, 32, 64};
@@ -167,44 +160,43 @@ static int ad7606_oversampling_get_index(unsigned int val)
        return -EINVAL;
 }
 
-static ssize_t ad7606_store_oversampling_ratio(struct device *dev,
-                                              struct device_attribute *attr,
-                                              const char *buf, size_t count)
+static int ad7606_write_raw(struct iio_dev *indio_dev,
+                           struct iio_chan_spec const *chan,
+                           int val,
+                           int val2,
+                           long mask)
 {
-       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct ad7606_state *st = iio_priv(indio_dev);
-       unsigned long lval;
        int ret;
 
-       ret = kstrtoul(buf, 10, &lval);
-       if (ret)
-               return ret;
+       switch (mask) {
+       case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+               if (val2)
+                       return -EINVAL;
+               ret = ad7606_oversampling_get_index(val);
+               if (ret < 0) {
+                       dev_err(st->dev, "oversampling %d is not supported\n",
+                               val);
+                       return ret;
+               }
 
-       ret = ad7606_oversampling_get_index(lval);
-       if (ret < 0) {
-               dev_err(dev, "oversampling %lu is not supported\n", lval);
-               return ret;
+               mutex_lock(&indio_dev->mlock);
+               gpio_set_value(st->pdata->gpio_os0, (ret >> 0) & 1);
+               gpio_set_value(st->pdata->gpio_os1, (ret >> 1) & 1);
+               gpio_set_value(st->pdata->gpio_os2, (ret >> 2) & 1);
+               st->oversampling = val;
+               mutex_unlock(&indio_dev->mlock);
+               return 0;
+       default:
+               return -EINVAL;
        }
-
-       mutex_lock(&indio_dev->mlock);
-       gpio_set_value(st->pdata->gpio_os0, (ret >> 0) & 1);
-       gpio_set_value(st->pdata->gpio_os1, (ret >> 1) & 1);
-       gpio_set_value(st->pdata->gpio_os2, (ret >> 2) & 1);
-       st->oversampling = lval;
-       mutex_unlock(&indio_dev->mlock);
-
-       return count;
 }
 
-static IIO_DEVICE_ATTR(oversampling_ratio, S_IRUGO | S_IWUSR,
-                      ad7606_show_oversampling_ratio,
-                      ad7606_store_oversampling_ratio, 0);
 static IIO_CONST_ATTR(oversampling_ratio_available, "0 2 4 8 16 32 64");
 
 static struct attribute *ad7606_attributes_os_and_range[] = {
        &iio_dev_attr_in_voltage_range.dev_attr.attr,
        &iio_const_attr_in_voltage_range_available.dev_attr.attr,
-       &iio_dev_attr_oversampling_ratio.dev_attr.attr,
        &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
        NULL,
 };
@@ -214,7 +206,6 @@ static const struct attribute_group ad7606_attribute_group_os_and_range = {
 };
 
 static struct attribute *ad7606_attributes_os[] = {
-       &iio_dev_attr_oversampling_ratio.dev_attr.attr,
        &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
        NULL,
 };
@@ -241,6 +232,8 @@ static const struct attribute_group ad7606_attribute_group_range = {
                .address = num,                                 \
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),   \
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
+               .info_mask_shared_by_all =                      \
+                       BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),  \
                .scan_index = num,                              \
                .scan_type = {                                  \
                        .sign = 's',                            \
@@ -429,12 +422,14 @@ static const struct iio_info ad7606_info_no_os_or_range = {
 static const struct iio_info ad7606_info_os_and_range = {
        .driver_module = THIS_MODULE,
        .read_raw = &ad7606_read_raw,
+       .write_raw = &ad7606_write_raw,
        .attrs = &ad7606_attribute_group_os_and_range,
 };
 
 static const struct iio_info ad7606_info_os = {
        .driver_module = THIS_MODULE,
        .read_raw = &ad7606_read_raw,
+       .write_raw = &ad7606_write_raw,
        .attrs = &ad7606_attribute_group_os,
 };