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

[Alison Schofield]

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 <amsfiel...@gmail.com>
Cc: Daniel Baluta <daniel.bal...@gmail.com>
---
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