Define a channel to read x,y and z together. This raw read takes
50% less time reading all axes together than individual reads.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
---
drivers/iio/magnetometer/ak8975.c | 58 ++++++++++++++++++++++++++-------------
1 file changed, 39 insertions(+), 19 deletions(-)
diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 24fc917..b6041ca 100644
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -1,3 +1,4 @@
+
/*
* A sensor driver for the magnetometer AK8975.
*
@@ -373,12 +374,14 @@ static int wait_conversion_complete_interrupt(struct ak8975_data *data)
}
/*
- * Emits the raw flux value for the x, y, or z axis.
+ * Emits the raw flux value for the x, y, or z individual or multiple axes
*/
-static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
+static int ak8975_read_axis(struct iio_dev *indio_dev, int axes_size,
+ int *indexes, int *vals)
{
struct ak8975_data *data = iio_priv(indio_dev);
struct i2c_client *client = data->client;
+ int i;
int ret;
mutex_lock(&data->lock);
@@ -421,36 +424,50 @@ static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
/* Read the flux value from the appropriate register
(the register is specified in the iio device attributes). */
- ret = i2c_smbus_read_word_data(client, ak8975_index_to_reg[index]);
- if (ret < 0) {
- dev_err(&client->dev, "Read axis data fails\n");
- goto exit;
+ for (i = 0; i < axes_size; ++i) {
+ ret = i2c_smbus_read_word_data(client,
+ ak8975_index_to_reg[*indexes++]);
+ if (ret < 0) {
+ dev_err(&client->dev, "Read axis data fails\n");
+ goto exit;
+ }
+ /* Clamp to valid range. */
+ vals[i] = clamp_t(s16, ret, -4096, 4095);
}
mutex_unlock(&data->lock);
- /* Clamp to valid range. */
- *val = clamp_t(s16, ret, -4096, 4095);
- return IIO_VAL_INT;
-
+ if (axes_size > 1)
+ return IIO_VAL_INT_MULTIPLE;
+ else
+ return IIO_VAL_INT;
exit:
mutex_unlock(&data->lock);
return ret;
}
-static int ak8975_read_raw(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- int *val, int *val2,
- long mask)
+static int ak8975_read_raw_multi(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int size, int *vals, int *val_len,
+ long mask)
{
struct ak8975_data *data = iio_priv(indio_dev);
+ int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
- return ak8975_read_axis(indio_dev, chan->address, val);
+ if (size >= 3 && chan->address == 3) {
+ int indexes[3] = {0, 1, 2};
+
+ ret = ak8975_read_axis(indio_dev, 3, indexes, vals);
+ *val_len = 3;
+ } else
+ ret = ak8975_read_axis(indio_dev, 1,
+ (int *)&chan->address, vals);
+ return ret;
case IIO_CHAN_INFO_SCALE:
- *val = 0;
- *val2 = data->raw_to_gauss[chan->address];
+ vals[0] = 0;
+ vals[1] = data->raw_to_gauss[chan->address];
return IIO_VAL_INT_PLUS_MICRO;
}
return -EINVAL;
@@ -467,11 +484,14 @@ static int ak8975_read_raw(struct iio_dev *indio_dev,
}
static const struct iio_chan_spec ak8975_channels[] = {
- AK8975_CHANNEL(X, 0), AK8975_CHANNEL(Y, 1), AK8975_CHANNEL(Z, 2),
+ AK8975_CHANNEL(X, 0),
+ AK8975_CHANNEL(Y, 1),
+ AK8975_CHANNEL(Z, 2),
+ AK8975_CHANNEL(X_AND_Y_AND_Z, 3)
};
static const struct iio_info ak8975_info = {
- .read_raw = &ak8975_read_raw,
+ .read_raw_multi = &ak8975_read_raw_multi,
.driver_module = THIS_MODULE,
};
--
1.8.3.2
--
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