While the iio buffer for the ti-ads1015 driver is enabled, reading the
raw ADC channel data is restricted. We usually use the
iio_device_claim_direct_mode()/iio_device_release_direct_mode() pair for
that.
This change consequently reverses the locking order for the driver's
private lock and indio_dev->mlock which acquired by
iio_device_claim_direct_mode() internally. But it's safe because there is
no other dependency between these locks.
Cc: Daniel Baluta <daniel.baluta@xxxxxxxxx>
Cc: Jonathan Cameron <jic23@xxxxxxxxxx>
Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
---
drivers/iio/adc/ti-ads1015.c | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)
diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c
index da25780..5568be4 100644
--- a/drivers/iio/adc/ti-ads1015.c
+++ b/drivers/iio/adc/ti-ads1015.c
@@ -347,34 +347,34 @@ static int ads1015_read_raw(struct iio_dev *indio_dev,
int ret, idx;
struct ads1015_data *data = iio_priv(indio_dev);
- mutex_lock(&indio_dev->mlock);
mutex_lock(&data->lock);
switch (mask) {
case IIO_CHAN_INFO_RAW: {
int shift = chan->scan_type.shift;
- if (iio_buffer_enabled(indio_dev)) {
- ret = -EBUSY;
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
break;
- }
ret = ads1015_set_power_state(data, true);
if (ret < 0)
- break;
+ goto release_direct;
ret = ads1015_get_adc_result(data, chan->address, val);
if (ret < 0) {
ads1015_set_power_state(data, false);
- break;
+ goto release_direct;
}
*val = sign_extend32(*val >> shift, 15 - shift);
ret = ads1015_set_power_state(data, false);
if (ret < 0)
- break;
+ goto release_direct;
ret = IIO_VAL_INT;
+release_direct:
+ iio_device_release_direct_mode(indio_dev);
break;
}
case IIO_CHAN_INFO_SCALE:
@@ -393,7 +393,6 @@ static int ads1015_read_raw(struct iio_dev *indio_dev,
break;
}
mutex_unlock(&data->lock);
- mutex_unlock(&indio_dev->mlock);
return ret;
}
--
2.7.4
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