[PATCH v2 11/16] iio: common: scmi_iio: do not use internal iio_dev lock

Nuno Sá
2022-10-04T13:50:18Z

The iio_device lock is only meant for internal use. Hence define a
device local lock to protect against concurrent accesses.

While at it, properly include "mutex.h" for mutex related APIs.

Signed-off-by: Nuno Sá <nuno.sa@analog.com>
---
drivers/iio/common/scmi_sensors/scmi_iio.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/common/scmi_sensors/scmi_iio.c b/drivers/iio/common/scmi_sensors/scmi_iio.c
index 54ccf19ab2bb..d92f7f651f7b 100644
--- a/drivers/iio/common/scmi_sensors/scmi_iio.c
+++ b/drivers/iio/common/scmi_sensors/scmi_iio.c
@@ -15,6 +15,7 @@
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/scmi_protocol.h>
#include <linux/time.h>
#include <linux/types.h>
@@ -27,6 +28,8 @@ struct scmi_iio_priv {
struct scmi_protocol_handle *ph;
const struct scmi_sensor_info *sensor_info;
struct iio_dev *indio_dev;
+ /* lock to protect against multiple access to the device */
+ struct mutex lock;
/* adding one additional channel for timestamp */
s64 iio_buf[SCMI_IIO_NUM_OF_AXIS + 1];
struct notifier_block sensor_update_nb;
@@ -198,13 +201,14 @@ static int scmi_iio_write_raw(struct iio_dev *iio_dev,
struct iio_chan_spec const *chan, int val,
int val2, long mask)
{
+ struct scmi_iio_priv *sensor = iio_priv(iio_dev);
int err;

switch (mask) {
case IIO_CHAN_INFO_SAMP_FREQ:
- mutex_lock(&iio_dev->mlock);
+ mutex_lock(&sensor->lock);
err = scmi_iio_set_odr_val(iio_dev, val, val2);
- mutex_unlock(&iio_dev->mlock);
+ mutex_unlock(&sensor->lock);
return err;
default:
return -EINVAL;
@@ -586,6 +590,7 @@ scmi_alloc_iiodev(struct scmi_device *sdev,
sensor->sensor_info = sensor_info;
sensor->sensor_update_nb.notifier_call = scmi_iio_sensor_update_cb;
sensor->indio_dev = iiodev;
+ mutex_init(&sensor->lock);

/* adding one additional channel for timestamp */
iiodev->num_channels = sensor_info->num_axis + 1;
--
2.37.3