[PATCH v2] iio: magnetometer: mag3110: claim direct mode during raw reads

From: Alison Schofield
Date: Fri Aug 19 2016 - 06:35:26 EST


Driver was checking for direct mode but not locking it. Use
claim/release helper functions to guarantee the device stays
in direct mode during raw reads.

Signed-off-by: Alison Schofield <amsfield22@xxxxxxxxx>
Cc: Daniel Baluta <daniel.baluta@xxxxxxxxx>
---
Changes in v2:
added breaks in switch to prevent fall through

drivers/iio/magnetometer/mag3110.c | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/iio/magnetometer/mag3110.c b/drivers/iio/magnetometer/mag3110.c
index f2be4a0..f2b3bd7 100644
--- a/drivers/iio/magnetometer/mag3110.c
+++ b/drivers/iio/magnetometer/mag3110.c
@@ -154,34 +154,41 @@ static int mag3110_read_raw(struct iio_dev *indio_dev,

switch (mask) {
case IIO_CHAN_INFO_RAW:
- if (iio_buffer_enabled(indio_dev))
- return -EBUSY;
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;

switch (chan->type) {
case IIO_MAGN: /* in 0.1 uT / LSB */
ret = mag3110_read(data, buffer);
if (ret < 0)
- return ret;
+ goto release;
*val = sign_extend32(
be16_to_cpu(buffer[chan->scan_index]), 15);
- return IIO_VAL_INT;
+ ret = IIO_VAL_INT;
+ break;
case IIO_TEMP: /* in 1 C / LSB */
mutex_lock(&data->lock);
ret = mag3110_request(data);
if (ret < 0) {
mutex_unlock(&data->lock);
- return ret;
+ goto release;
}
ret = i2c_smbus_read_byte_data(data->client,
MAG3110_DIE_TEMP);
mutex_unlock(&data->lock);
if (ret < 0)
- return ret;
+ goto release;
*val = sign_extend32(ret, 7);
- return IIO_VAL_INT;
+ ret = IIO_VAL_INT;
+ break;
default:
- return -EINVAL;
+ ret = -EINVAL;
}
+release:
+ iio_device_release_direct_mode(indio_dev);
+ return ret;
+
case IIO_CHAN_INFO_SCALE:
switch (chan->type) {
case IIO_MAGN:
--
2.1.4