[PATCH] iio:st_sensors: Fix oops when probing SPI devices

[Alban Bedel <alban.bedel@avionic-design.de>]

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>
---
 drivers/iio/accel/st_accel_core.c               | 1 +
 drivers/iio/common/st_sensors/st_sensors_core.c | 2 --
 drivers/iio/gyro/st_gyro_core.c                 | 1 +
 drivers/iio/magnetometer/st_magn_core.c         | 1 +
 drivers/iio/pressure/st_pressure_core.c         | 1 +
 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 58d1d13..211b132 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 edd13d2..8dd0477 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 21395f2..ffe9664 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 8ade473..2e56f81 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 97baf40d..e881fa6 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);
 
-- 
2.3.5