[PATCH] iio: imu: kmx61: Use guard(mutex)() family over manual locking

Maxwell Doose
2026-05-02T03:24:57Z

Include linux/cleanup.h to take advantage of new macros.

Replace manual mutex_lock() and mutex_unlock() calls across the file
with guard(mutex)() and scoped_guard() where appropriate. This will help
modernize the driver with up-to-date functions/macros.

Remove now redundant gotos and ret variables, as the new RAII macros
make them unneeded.

Signed-off-by: Maxwell Doose <m32285159@gmail.com>
---
drivers/iio/imu/kmx61.c | 74 ++++++++++++++---------------------------
1 file changed, 25 insertions(+), 49 deletions(-)

diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c
index 3cd91d8a89ee..2baaca129601 100644
--- a/drivers/iio/imu/kmx61.c
+++ b/drivers/iio/imu/kmx61.c
@@ -7,6 +7,7 @@
* IIO driver for KMX61 (7-bit I2C slave address 0x0E or 0x0F).
*/

+#include <linux/cleanup.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/mod_devicetable.h>
@@ -794,25 +795,21 @@ static int kmx61_read_raw(struct iio_dev *indio_dev,
default:
return -EINVAL;
}
- mutex_lock(&data->lock);
+ guard(mutex)(&data->lock);

ret = kmx61_set_power_state(data, true, chan->address);
- if (ret) {
- mutex_unlock(&data->lock);
+ if (ret)
return ret;
- }

ret = kmx61_read_measurement(data, base_reg, chan->scan_index);
if (ret < 0) {
kmx61_set_power_state(data, false, chan->address);
- mutex_unlock(&data->lock);
return ret;
}
*val = sign_extend32(ret >> chan->scan_type.shift,
chan->scan_type.realbits - 1);
ret = kmx61_set_power_state(data, false, chan->address);

- mutex_unlock(&data->lock);
if (ret)
return ret;
return IIO_VAL_INT;
@@ -834,9 +831,8 @@ static int kmx61_read_raw(struct iio_dev *indio_dev,
if (chan->type != IIO_ACCEL && chan->type != IIO_MAGN)
return -EINVAL;

- mutex_lock(&data->lock);
- ret = kmx61_get_odr(data, val, val2, chan->address);
- mutex_unlock(&data->lock);
+ scoped_guard(mutex, &data->lock)
+ ret = kmx61_get_odr(data, val, val2, chan->address);
if (ret)
return -EINVAL;
return IIO_VAL_INT_PLUS_MICRO;
@@ -856,19 +852,15 @@ static int kmx61_write_raw(struct iio_dev *indio_dev,
if (chan->type != IIO_ACCEL && chan->type != IIO_MAGN)
return -EINVAL;

- mutex_lock(&data->lock);
- ret = kmx61_set_odr(data, val, val2, chan->address);
- mutex_unlock(&data->lock);
- return ret;
+ guard(mutex)(&data->lock);
+ return kmx61_set_odr(data, val, val2, chan->address);
case IIO_CHAN_INFO_SCALE:
switch (chan->type) {
case IIO_ACCEL:
if (val != 0)
return -EINVAL;
- mutex_lock(&data->lock);
- ret = kmx61_set_scale(data, val2);
- mutex_unlock(&data->lock);
- return ret;
+ guard(mutex)(&data->lock);
+ return kmx61_set_scale(data, val2);
default:
return -EINVAL;
}
@@ -945,28 +937,25 @@ static int kmx61_write_event_config(struct iio_dev *indio_dev,
if (state && data->ev_enable_state)
return 0;

- mutex_lock(&data->lock);
+ guard(mutex)(&data->lock);

if (!state && data->motion_trig_on) {
data->ev_enable_state = false;
- goto err_unlock;
+ return ret;
}

ret = kmx61_set_power_state(data, state, KMX61_ACC);
if (ret < 0)
- goto err_unlock;
+ return ret;

ret = kmx61_setup_any_motion_interrupt(data, state);
if (ret < 0) {
kmx61_set_power_state(data, false, KMX61_ACC);
- goto err_unlock;
+ return ret;
}

data->ev_enable_state = state;

-err_unlock:
- mutex_unlock(&data->lock);
-
return ret;
}

@@ -1020,11 +1009,11 @@ static int kmx61_data_rdy_trigger_set_state(struct iio_trigger *trig,
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct kmx61_data *data = kmx61_get_data(indio_dev);

- mutex_lock(&data->lock);
+ guard(mutex)(&data->lock);

if (!state && data->ev_enable_state && data->motion_trig_on) {
data->motion_trig_on = false;
- goto err_unlock;
+ return ret;
}

if (data->acc_dready_trig == trig || data->motion_trig == trig)
@@ -1034,7 +1023,7 @@ static int kmx61_data_rdy_trigger_set_state(struct iio_trigger *trig,

ret = kmx61_set_power_state(data, state, device);
if (ret < 0)
- goto err_unlock;
+ return ret;

if (data->acc_dready_trig == trig || data->mag_dready_trig == trig)
ret = kmx61_setup_new_data_interrupt(data, state, device);
@@ -1042,7 +1031,7 @@ static int kmx61_data_rdy_trigger_set_state(struct iio_trigger *trig,
ret = kmx61_setup_any_motion_interrupt(data, state);
if (ret < 0) {
kmx61_set_power_state(data, false, device);
- goto err_unlock;
+ return ret;
}

if (data->acc_dready_trig == trig)
@@ -1051,8 +1040,6 @@ static int kmx61_data_rdy_trigger_set_state(struct iio_trigger *trig,
data->mag_dready_trig_on = state;
else
data->motion_trig_on = state;
-err_unlock:
- mutex_unlock(&data->lock);

return ret;
}
@@ -1195,19 +1182,17 @@ static irqreturn_t kmx61_trigger_handler(int irq, void *p)
else
base = KMX61_MAG_XOUT_L;

- mutex_lock(&data->lock);
+ guard(mutex)(&data->lock);
iio_for_each_active_channel(indio_dev, bit) {
ret = kmx61_read_measurement(data, base, bit);
if (ret < 0) {
- mutex_unlock(&data->lock);
- goto err;
+ iio_trigger_notify_done(indio_dev->trig);
+ return IRQ_HANDLED;
}
buffer[i++] = ret;
}
- mutex_unlock(&data->lock);

iio_push_to_buffers(indio_dev, buffer);
-err:
iio_trigger_notify_done(indio_dev->trig);

return IRQ_HANDLED;
@@ -1419,22 +1404,17 @@ static void kmx61_remove(struct i2c_client *client)
iio_trigger_unregister(data->motion_trig);
}

- mutex_lock(&data->lock);
+ guard(mutex)(&data->lock);
kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, true);
- mutex_unlock(&data->lock);
}

static int kmx61_suspend(struct device *dev)
{
- int ret;
struct kmx61_data *data = i2c_get_clientdata(to_i2c_client(dev));

- mutex_lock(&data->lock);
- ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG,
+ guard(mutex)(&data->lock);
+ return kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG,
false);
- mutex_unlock(&data->lock);
-
- return ret;
}

static int kmx61_resume(struct device *dev)
@@ -1453,13 +1433,9 @@ static int kmx61_resume(struct device *dev)
static int kmx61_runtime_suspend(struct device *dev)
{
struct kmx61_data *data = i2c_get_clientdata(to_i2c_client(dev));
- int ret;
-
- mutex_lock(&data->lock);
- ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, true);
- mutex_unlock(&data->lock);

- return ret;
+ guard(mutex)(&data->lock);
+ return kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG, true);
}

static int kmx61_runtime_resume(struct device *dev)
--
2.53.0