iio:st_sensors: Fix oops when probing SPI devices

In SPI mode the transfer buffer is locked with a mutex. However this
mutex is only initilized after the probe, but some transfer needs to
be done in the probe.

To fix this bug we move the mutex initialization at the beginning of
the device probe.

Signed-off-by: Alban Bedel <alban.bedel@avionic-design.de>
Acked-by: Denis Ciocca <denis.ciocca@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

5 files changed, 4 insertions, 2 deletions

diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c
index 58d1d13d552a..211b13271c61 100644
--- a/drivers/iio/accel/st_accel_core.c
+++ b/drivers/iio/accel/st_accel_core.c
@@ -546,6 +546,7 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
 
         indio_dev->modes = INDIO_DIRECT_MODE;
         indio_dev->info = &accel_info;
+        mutex_init(&adata->tb.buf_lock);
 
         st_sensors_power_enable(indio_dev);
 
diff --git a/drivers/iio/common/st_sensors/st_sensors_core.c b/drivers/iio/common/st_sensors/st_sensors_core.c
index edd13d2b4121..8dd0477e201c 100644
--- a/drivers/iio/common/st_sensors/st_sensors_core.c
+++ b/drivers/iio/common/st_sensors/st_sensors_core.c
@@ -304,8 +304,6 @@ int st_sensors_init_sensor(struct iio_dev *indio_dev,
         struct st_sensors_platform_data *of_pdata;
         int err = 0;
 
-        mutex_init(&sdata->tb.buf_lock);
-
         /* If OF/DT pdata exists, it will take precedence of anything else */
         of_pdata = st_sensors_of_probe(indio_dev->dev.parent, pdata);
         if (of_pdata)
diff --git a/drivers/iio/gyro/st_gyro_core.c b/drivers/iio/gyro/st_gyro_core.c
index 21395f26d227..ffe96642b6d0 100644
--- a/drivers/iio/gyro/st_gyro_core.c
+++ b/drivers/iio/gyro/st_gyro_core.c
@@ -400,6 +400,7 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
 
         indio_dev->modes = INDIO_DIRECT_MODE;
         indio_dev->info = &gyro_info;
+        mutex_init(&gdata->tb.buf_lock);
 
         st_sensors_power_enable(indio_dev);
 
diff --git a/drivers/iio/magnetometer/st_magn_core.c b/drivers/iio/magnetometer/st_magn_core.c
index 8ade473f99fe..2e56f812a644 100644
--- a/drivers/iio/magnetometer/st_magn_core.c
+++ b/drivers/iio/magnetometer/st_magn_core.c
@@ -369,6 +369,7 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
 
         indio_dev->modes = INDIO_DIRECT_MODE;
         indio_dev->info = &magn_info;
+        mutex_init(&mdata->tb.buf_lock);
 
         st_sensors_power_enable(indio_dev);
 
diff --git a/drivers/iio/pressure/st_pressure_core.c b/drivers/iio/pressure/st_pressure_core.c
index 97baf40d424b..e881fa6291e9 100644
--- a/drivers/iio/pressure/st_pressure_core.c
+++ b/drivers/iio/pressure/st_pressure_core.c
@@ -417,6 +417,7 @@ int st_press_common_probe(struct iio_dev *indio_dev)
 
         indio_dev->modes = INDIO_DIRECT_MODE;
         indio_dev->info = &press_info;
+        mutex_init(&press_data->tb.buf_lock);
 
         st_sensors_power_enable(indio_dev);