[PATCH] iio/accel/bmc150: Improve unlocking of a mutex in two functions

From: SF Markus Elfring
Date: Wed Oct 25 2017 - 10:33:43 EST


From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Wed, 25 Oct 2017 16:26:29 +0200

Add a jump target so that a call of the function "mutex_unlock" is mostly
stored at the end of these function implementations.
Replace five calls by goto statements.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/iio/accel/bmc150-accel-core.c | 32 ++++++++++++++------------------
1 file changed, 14 insertions(+), 18 deletions(-)

diff --git a/drivers/iio/accel/bmc150-accel-core.c b/drivers/iio/accel/bmc150-accel-core.c
index 870f92ef61c2..f2a85a11a5e4 100644
--- a/drivers/iio/accel/bmc150-accel-core.c
+++ b/drivers/iio/accel/bmc150-accel-core.c
@@ -554,18 +554,15 @@ static int bmc150_accel_get_axis(struct bmc150_accel_data *data,

mutex_lock(&data->mutex);
ret = bmc150_accel_set_power_state(data, true);
- if (ret < 0) {
- mutex_unlock(&data->mutex);
- return ret;
- }
+ if (ret < 0)
+ goto unlock_after_failure;

ret = regmap_bulk_read(data->regmap, BMC150_ACCEL_AXIS_TO_REG(axis),
&raw_val, sizeof(raw_val));
if (ret < 0) {
dev_err(dev, "Error reading axis %d\n", axis);
bmc150_accel_set_power_state(data, false);
- mutex_unlock(&data->mutex);
- return ret;
+ goto unlock_after_failure;
}
*val = sign_extend32(le16_to_cpu(raw_val) >> chan->scan_type.shift,
chan->scan_type.realbits - 1);
@@ -575,6 +572,10 @@ static int bmc150_accel_get_axis(struct bmc150_accel_data *data,
return ret;

return IIO_VAL_INT;
+
+unlock_after_failure:
+ mutex_unlock(&data->mutex);
+ return ret;
}

static int bmc150_accel_read_raw(struct iio_dev *indio_dev,
@@ -1170,28 +1171,23 @@ static int bmc150_accel_trigger_set_state(struct iio_trigger *trig,
mutex_lock(&data->mutex);

if (t->enabled == state) {
- mutex_unlock(&data->mutex);
- return 0;
+ ret = 0;
+ goto unlock;
}

if (t->setup) {
ret = t->setup(t, state);
- if (ret < 0) {
- mutex_unlock(&data->mutex);
- return ret;
- }
+ if (ret < 0)
+ goto unlock;
}

ret = bmc150_accel_set_interrupt(data, t->intr, state);
- if (ret < 0) {
- mutex_unlock(&data->mutex);
- return ret;
- }
+ if (ret < 0)
+ goto unlock;

t->enabled = state;
-
+unlock:
mutex_unlock(&data->mutex);
-
return ret;
}

--
2.14.3