staging: iio: ad7606: replace range/range_available with corresponding scale

Eliminate the non-standard attributes in_voltage_range and
in_voltage_range_available. Implement in_voltage_scale_available in place
of these attributes and update the SCALE accordingly. The array
scale_avail is introduced to hold the available scale values.

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.c b/drivers/staging/iio/adc/ad7606.c
index 453190864b2ffc60b9b7515ce55ee53f2ad1c11e..9dbfa64b1e53f14edefe4a5c7df5577f9adddf9d 100644 (file)
--- a/drivers/staging/iio/adc/ad7606.c
+++ b/drivers/staging/iio/adc/ad7606.c
@@ -26,6 +26,11 @@
 
 #include "ad7606.h"
 
+/* Scales are computed as 2.5/2**16 and 5/2**16 respectively */
+static const unsigned int scale_avail[2][2] = {
+       {0, 38147}, {0, 76294}
+};
+
 static int ad7606_reset(struct ad7606_state *st)
 {
        if (st->gpio_reset) {
@@ -151,9 +156,9 @@ static int ad7606_read_raw(struct iio_dev *indio_dev,
                *val = (short)ret;
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
-               *val = st->range * 2;
-               *val2 = st->chip_info->channels[0].scan_type.realbits;
-               return IIO_VAL_FRACTIONAL_LOG2;
+               *val = scale_avail[st->range][0];
+               *val2 = scale_avail[st->range][1];
+               return IIO_VAL_INT_PLUS_MICRO;
        case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
                *val = st->oversampling;
                return IIO_VAL_INT;
@@ -161,42 +166,22 @@ static int ad7606_read_raw(struct iio_dev *indio_dev,
        return -EINVAL;
 }
 
-static ssize_t ad7606_show_range(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->range);
-}
-
-static ssize_t ad7606_store_range(struct device *dev,
-                                 struct device_attribute *attr,
-                                 const char *buf, size_t count)
+static ssize_t in_voltage_scale_available_show(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);
-       unsigned long lval;
-       int ret;
-
-       ret = kstrtoul(buf, 10, &lval);
-       if (ret)
-               return ret;
+       int i, len = 0;
 
-       if (!(lval == 5000 || lval == 10000))
-               return -EINVAL;
+       for (i = 0; i < ARRAY_SIZE(scale_avail); i++)
+               len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06u ",
+                                scale_avail[i][0], scale_avail[i][1]);
 
-       mutex_lock(&indio_dev->mlock);
-       gpiod_set_value(st->gpio_range, lval == 10000);
-       st->range = lval;
-       mutex_unlock(&indio_dev->mlock);
+       buf[len - 1] = '\n';
 
-       return count;
+       return len;
 }
 
-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 IIO_DEVICE_ATTR_RO(in_voltage_scale_available, 0);
 
 static int ad7606_oversampling_get_index(unsigned int val)
 {
@@ -218,9 +203,23 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
 {
        struct ad7606_state *st = iio_priv(indio_dev);
        int values[3];
-       int ret;
+       int ret, i;
 
        switch (mask) {
+       case IIO_CHAN_INFO_SCALE:
+               ret = -EINVAL;
+               mutex_lock(&indio_dev->mlock);
+               for (i = 0; i < ARRAY_SIZE(scale_avail); i++)
+                       if (val2 == scale_avail[i][1]) {
+                               gpiod_set_value(st->gpio_range, i);
+                               st->range = i;
+
+                               ret = 0;
+                               break;
+                       }
+               mutex_unlock(&indio_dev->mlock);
+
+               return ret;
        case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
                if (val2)
                        return -EINVAL;
@@ -247,8 +246,7 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
 static IIO_CONST_ATTR(oversampling_ratio_available, "1 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_in_voltage_scale_available.dev_attr.attr,
        &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
        NULL,
 };
@@ -267,8 +265,7 @@ static const struct attribute_group ad7606_attribute_group_os = {
 };
 
 static struct attribute *ad7606_attributes_range[] = {
-       &iio_dev_attr_in_voltage_range.dev_attr.attr,
-       &iio_const_attr_in_voltage_range_available.dev_attr.attr,
+       &iio_dev_attr_in_voltage_scale_available.dev_attr.attr,
        NULL,
 };
 
@@ -397,6 +394,7 @@ static const struct iio_info ad7606_info_os = {
 static const struct iio_info ad7606_info_range = {
        .driver_module = THIS_MODULE,
        .read_raw = &ad7606_read_raw,
+       .write_raw = &ad7606_write_raw,
        .attrs = &ad7606_attribute_group_range,
 };
 
@@ -417,7 +415,8 @@ int ad7606_probe(struct device *dev, int irq, void __iomem *base_address,
        st->dev = dev;
        st->bops = bops;
        st->base_address = base_address;
-       st->range = 5000;
+       /* tied to logic low, analog input range is +/- 5V */
+       st->range = 0;
        st->oversampling = 1;
        INIT_WORK(&st->poll_work, &ad7606_poll_bh_to_ring);
 
@@ -525,7 +524,7 @@ static int ad7606_resume(struct device *dev)
        struct ad7606_state *st = iio_priv(indio_dev);
 
        if (st->gpio_standby) {
-               gpiod_set_value(st->gpio_range, st->range == 10000);
+               gpiod_set_value(st->gpio_range, st->range);
                gpiod_set_value(st->gpio_standby, 1);
                ad7606_reset(st);
        }