iio:ad7266: Report scale as fractional value
authorLars-Peter Clausen <lars@metafoo.de>
Sat, 28 Sep 2013 09:31:00 +0000 (10:31 +0100)
committerJonathan Cameron <jic23@kernel.org>
Tue, 1 Oct 2013 15:19:12 +0000 (16:19 +0100)
Move the complexity of calculating the fixed point scale to the core.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
drivers/iio/adc/ad7266.c

index 656aa3e102f288ffa0cba17086f695dbb011e1e9..f5723cbd2032ce4a8ef0acd71e1261048796e37c 100644 (file)
@@ -27,7 +27,7 @@
 struct ad7266_state {
        struct spi_device       *spi;
        struct regulator        *reg;
-       unsigned long           vref_uv;
+       unsigned long           vref_mv;
 
        struct spi_transfer     single_xfer[3];
        struct spi_message      single_msg;
@@ -156,7 +156,7 @@ static int ad7266_read_raw(struct iio_dev *indio_dev,
        struct iio_chan_spec const *chan, int *val, int *val2, long m)
 {
        struct ad7266_state *st = iio_priv(indio_dev);
-       unsigned long scale_uv;
+       unsigned long scale_mv;
        int ret;
 
        switch (m) {
@@ -174,16 +174,15 @@ static int ad7266_read_raw(struct iio_dev *indio_dev,
 
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
-               scale_uv = (st->vref_uv * 100);
+               scale_mv = st->vref_mv;
                if (st->mode == AD7266_MODE_DIFF)
-                       scale_uv *= 2;
+                       scale_mv *= 2;
                if (st->range == AD7266_RANGE_2VREF)
-                       scale_uv *= 2;
+                       scale_mv *= 2;
 
-               scale_uv >>= chan->scan_type.realbits;
-               *val =  scale_uv / 100000;
-               *val2 = (scale_uv % 100000) * 10;
-               return IIO_VAL_INT_PLUS_MICRO;
+               *val = scale_mv;
+               *val2 = chan->scan_type.realbits;
+               return IIO_VAL_FRACTIONAL_LOG2;
        case IIO_CHAN_INFO_OFFSET:
                if (st->range == AD7266_RANGE_2VREF &&
                        st->mode != AD7266_MODE_DIFF)
@@ -414,10 +413,10 @@ static int ad7266_probe(struct spi_device *spi)
                if (ret < 0)
                        goto error_disable_reg;
 
-               st->vref_uv = ret;
+               st->vref_mv = ret / 1000;
        } else {
                /* Use internal reference */
-               st->vref_uv = 2500000;
+               st->vref_mv = 2500;
        }
 
        if (pdata) {