iio: light: bu27034: Fix scale format

The driver is expecting accuracy of NANOs for intensity scale in
raw_write. The IIO core is however defaulting to MICROs. This leads the
raw-write of smallest scales to never succeed as correct selector(s) are
not found.

Fix this by implementing the .write_raw_get_fmt callback to use NANO
accuracy for writes of IIO_CHAN_INFO_SCALE.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Fixes: e52afbd61039 ("iio: light: ROHM BU27034 Ambient Light Sensor")
Link: https://lore.kernel.org/r/5369117315cf05b88cf0ccb87373fd77190f6ca2.1686648422.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/light/rohm-bu27034.c b/drivers/iio/light/rohm-bu27034.c
index e63ef57..bf3de85 100644 (file)
--- a/drivers/iio/light/rohm-bu27034.c
+++ b/drivers/iio/light/rohm-bu27034.c
@@ -575,7 +575,7 @@ static int bu27034_set_scale(struct bu27034_data *data, int chan,
                return -EINVAL;
 
        if (chan == BU27034_CHAN_ALS) {
-               if (val == 0 && val2 == 1000)
+               if (val == 0 && val2 == 1000000)
                        return 0;
 
                return -EINVAL;
@@ -587,7 +587,7 @@ static int bu27034_set_scale(struct bu27034_data *data, int chan,
                goto unlock_out;
 
        ret = iio_gts_find_gain_sel_for_scale_using_time(&data->gts, time_sel,
-                                               val, val2 * 1000, &gain_sel);
+                                               val, val2, &gain_sel);
        if (ret) {
                /*
                 * Could not support scale with given time. Need to change time.
@@ -624,7 +624,7 @@ static int bu27034_set_scale(struct bu27034_data *data, int chan,
 
                        /* Can we provide requested scale with this time? */
                        ret = iio_gts_find_gain_sel_for_scale_using_time(
-                               &data->gts, new_time_sel, val, val2 * 1000,
+                               &data->gts, new_time_sel, val, val2,
                                &gain_sel);
                        if (ret)
                                continue;
@@ -1217,6 +1217,21 @@ static int bu27034_read_raw(struct iio_dev *idev,
        }
 }
 
+static int bu27034_write_raw_get_fmt(struct iio_dev *indio_dev,
+                                    struct iio_chan_spec const *chan,
+                                    long mask)
+{
+
+       switch (mask) {
+       case IIO_CHAN_INFO_SCALE:
+               return IIO_VAL_INT_PLUS_NANO;
+       case IIO_CHAN_INFO_INT_TIME:
+               return IIO_VAL_INT_PLUS_MICRO;
+       default:
+               return -EINVAL;
+       }
+}
+
 static int bu27034_write_raw(struct iio_dev *idev,
                             struct iio_chan_spec const *chan,
                             int val, int val2, long mask)
@@ -1267,6 +1282,7 @@ static int bu27034_read_avail(struct iio_dev *idev,
 static const struct iio_info bu27034_info = {
        .read_raw = &bu27034_read_raw,
        .write_raw = &bu27034_write_raw,
+       .write_raw_get_fmt = &bu27034_write_raw_get_fmt,
        .read_avail = &bu27034_read_avail,
 };