iio: potentiometer: tpl0102: add IIO_AVAIL_RANGE support

Report the step range of the respective potentiometers that are
possible to userspace.

Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/potentiometer/tpl0102.c b/drivers/iio/potentiometer/tpl0102.c
index 8e8adabe672b5a22ad5fd2836ffa222ebbad1e36..a0a07e47f13f278b055ffcf8b1a0cc3a2bcf1f88 100644 (file)
--- a/drivers/iio/potentiometer/tpl0102.c
+++ b/drivers/iio/potentiometer/tpl0102.c
@@ -15,7 +15,7 @@
 
 struct tpl0102_cfg {
        int wipers;
-       int max_pos;
+       int avail[3];
        int kohms;
 };
 
@@ -28,11 +28,11 @@ enum tpl0102_type {
 
 static const struct tpl0102_cfg tpl0102_cfg[] = {
        /* on-semiconductor parts */
-       [CAT5140_503] = { .wipers = 1, .max_pos = 256, .kohms = 50, },
-       [CAT5140_104] = { .wipers = 1, .max_pos = 256, .kohms = 100, },
+       [CAT5140_503] = { .wipers = 1, .avail = { 0, 1, 255 }, .kohms = 50, },
+       [CAT5140_104] = { .wipers = 1, .avail = { 0, 1, 255 }, .kohms = 100, },
        /* ti parts */
-       [TPL0102_104] = { .wipers = 2, .max_pos = 256, .kohms = 100 },
-       [TPL0401_103] = { .wipers = 1, .max_pos = 128, .kohms = 10, },
+       [TPL0102_104] = { .wipers = 2, .avail = { 0, 1, 255 }, .kohms = 100 },
+       [TPL0401_103] = { .wipers = 1, .avail = { 0, 1, 127 }, .kohms = 10, },
 };
 
 struct tpl0102_data {
@@ -52,6 +52,7 @@ static const struct regmap_config tpl0102_regmap_config = {
        .channel = (ch),                                        \
        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),           \
        .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),   \
+       .info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW), \
 }
 
 static const struct iio_chan_spec tpl0102_channels[] = {
@@ -73,13 +74,31 @@ static int tpl0102_read_raw(struct iio_dev *indio_dev,
        }
        case IIO_CHAN_INFO_SCALE:
                *val = 1000 * data->cfg->kohms;
-               *val2 = data->cfg->max_pos;
+               *val2 = data->cfg->avail[2] + 1;
                return IIO_VAL_FRACTIONAL;
        }
 
        return -EINVAL;
 }
 
+static int tpl0102_read_avail(struct iio_dev *indio_dev,
+                             struct iio_chan_spec const *chan,
+                             const int **vals, int *type, int *length,
+                             long mask)
+{
+       struct tpl0102_data *data = iio_priv(indio_dev);
+
+       switch (mask) {
+       case IIO_CHAN_INFO_RAW:
+               *length = ARRAY_SIZE(data->cfg->avail);
+               *vals = data->cfg->avail;
+               *type = IIO_VAL_INT;
+               return IIO_AVAIL_RANGE;
+       }
+
+       return -EINVAL;
+}
+
 static int tpl0102_write_raw(struct iio_dev *indio_dev,
                             struct iio_chan_spec const *chan,
                             int val, int val2, long mask)
@@ -89,7 +108,7 @@ static int tpl0102_write_raw(struct iio_dev *indio_dev,
        if (mask != IIO_CHAN_INFO_RAW)
                return -EINVAL;
 
-       if (val >= data->cfg->max_pos || val < 0)
+       if (val > data->cfg->avail[2] || val < 0)
                return -EINVAL;
 
        return regmap_write(data->regmap, chan->channel, val);
@@ -97,6 +116,7 @@ static int tpl0102_write_raw(struct iio_dev *indio_dev,
 
 static const struct iio_info tpl0102_info = {
        .read_raw = tpl0102_read_raw,
+       .read_avail = tpl0102_read_avail,
        .write_raw = tpl0102_write_raw,
 };