iio:st_sensors: remove buffer allocation at each buffer enable

This patch is removing the buffer allocation at each buffer enable.
We just allocate enough memory in the main structure during probe
to cover maximum size needed (that anyway is pretty small) [16bytes].

Signed-off-by: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

4 files changed, 4 insertions, 44 deletions

diff --git a/drivers/iio/accel/st_accel_buffer.c b/drivers/iio/accel/st_accel_buffer.c
index 59dcef02ec19..9f2b40474b8e 100644
--- a/drivers/iio/accel/st_accel_buffer.c
+++ b/drivers/iio/accel/st_accel_buffer.c
@@ -31,17 +31,11 @@ int st_accel_trig_set_state(struct iio_trigger *trig, bool state)
 
 static int st_accel_buffer_postenable(struct iio_dev *indio_dev)
 {
-	struct st_sensor_data *adata = iio_priv(indio_dev);
 	int err;
 
-	adata->buffer_data = kmalloc(indio_dev->scan_bytes,
-				     GFP_DMA | GFP_KERNEL);
-	if (!adata->buffer_data)
-		return -ENOMEM;
-
 	err = iio_triggered_buffer_postenable(indio_dev);
 	if (err < 0)
-		goto st_accel_free_buffer;
+		return err;
 
 	err = st_sensors_set_axis_enable(indio_dev,
 					 (u8)indio_dev->active_scan_mask[0]);
@@ -58,14 +52,11 @@ st_accel_buffer_enable_all_axis:
 	st_sensors_set_axis_enable(indio_dev, ST_SENSORS_ENABLE_ALL_AXIS);
 st_accel_buffer_predisable:
 	iio_triggered_buffer_predisable(indio_dev);
-st_accel_free_buffer:
-	kfree(adata->buffer_data);
 	return err;
 }
 
 static int st_accel_buffer_predisable(struct iio_dev *indio_dev)
 {
-	struct st_sensor_data *adata = iio_priv(indio_dev);
 	int err, err2;
 
 	err = st_sensors_set_enable(indio_dev, false);
@@ -79,7 +70,6 @@ st_accel_buffer_predisable:
 	if (!err)
 		err = err2;
 
-	kfree(adata->buffer_data);
 	return err;
 }
 
diff --git a/drivers/iio/gyro/st_gyro_buffer.c b/drivers/iio/gyro/st_gyro_buffer.c
index c6ddfecc1fc3..7465ad62391c 100644
--- a/drivers/iio/gyro/st_gyro_buffer.c
+++ b/drivers/iio/gyro/st_gyro_buffer.c
@@ -31,17 +31,11 @@ int st_gyro_trig_set_state(struct iio_trigger *trig, bool state)
 
 static int st_gyro_buffer_postenable(struct iio_dev *indio_dev)
 {
-	struct st_sensor_data *gdata = iio_priv(indio_dev);
 	int err;
 
-	gdata->buffer_data = kmalloc(indio_dev->scan_bytes,
-				     GFP_DMA | GFP_KERNEL);
-	if (!gdata->buffer_data)
-		return -ENOMEM;
-
 	err = iio_triggered_buffer_postenable(indio_dev);
 	if (err < 0)
-		goto st_gyro_free_buffer;
+		return err;
 
 	err = st_sensors_set_axis_enable(indio_dev,
 					 (u8)indio_dev->active_scan_mask[0]);
@@ -58,15 +52,12 @@ st_gyro_buffer_enable_all_axis:
 	st_sensors_set_axis_enable(indio_dev, ST_SENSORS_ENABLE_ALL_AXIS);
 st_gyro_buffer_predisable:
 	iio_triggered_buffer_predisable(indio_dev);
-st_gyro_free_buffer:
-	kfree(gdata->buffer_data);
 	return err;
 }
 
 static int st_gyro_buffer_predisable(struct iio_dev *indio_dev)
 {
 	int err, err2;
-	struct st_sensor_data *gdata = iio_priv(indio_dev);
 
 	err = st_sensors_set_enable(indio_dev, false);
 	if (err < 0)
@@ -79,7 +70,6 @@ st_gyro_buffer_predisable:
 	if (!err)
 		err = err2;
 
-	kfree(gdata->buffer_data);
 	return err;
 }
 
diff --git a/drivers/iio/magnetometer/st_magn_buffer.c b/drivers/iio/magnetometer/st_magn_buffer.c
index 658d627dad8e..bb425c167a96 100644
--- a/drivers/iio/magnetometer/st_magn_buffer.c
+++ b/drivers/iio/magnetometer/st_magn_buffer.c
@@ -31,17 +31,11 @@ int st_magn_trig_set_state(struct iio_trigger *trig, bool state)
 
 static int st_magn_buffer_postenable(struct iio_dev *indio_dev)
 {
-	struct st_sensor_data *mdata = iio_priv(indio_dev);
 	int err;
 
-	mdata->buffer_data = kmalloc(indio_dev->scan_bytes,
-				     GFP_DMA | GFP_KERNEL);
-	if (!mdata->buffer_data)
-		return -ENOMEM;
-
 	err = iio_triggered_buffer_postenable(indio_dev);
 	if (err < 0)
-		goto st_magn_free_buffer;
+		return err;
 
 	err = st_sensors_set_enable(indio_dev, true);
 	if (err < 0)
@@ -51,14 +45,11 @@ static int st_magn_buffer_postenable(struct iio_dev *indio_dev)
 
 st_magn_buffer_predisable:
 	iio_triggered_buffer_predisable(indio_dev);
-st_magn_free_buffer:
-	kfree(mdata->buffer_data);
 	return err;
 }
 
 static int st_magn_buffer_predisable(struct iio_dev *indio_dev)
 {
-	struct st_sensor_data *mdata = iio_priv(indio_dev);
 	int err, err2;
 
 	err = st_sensors_set_enable(indio_dev, false);
@@ -67,7 +58,6 @@ static int st_magn_buffer_predisable(struct iio_dev *indio_dev)
 	if (!err)
 		err = err2;
 
-	kfree(mdata->buffer_data);
 	return err;
 }
 
diff --git a/drivers/iio/pressure/st_pressure_buffer.c b/drivers/iio/pressure/st_pressure_buffer.c
index 77cb2d862f19..418dbf9e6e1e 100644
--- a/drivers/iio/pressure/st_pressure_buffer.c
+++ b/drivers/iio/pressure/st_pressure_buffer.c
@@ -31,17 +31,11 @@ int st_press_trig_set_state(struct iio_trigger *trig, bool state)
 
 static int st_press_buffer_postenable(struct iio_dev *indio_dev)
 {
-	struct st_sensor_data *press_data = iio_priv(indio_dev);
 	int err;
 
-	press_data->buffer_data = kmalloc(indio_dev->scan_bytes,
-					  GFP_DMA | GFP_KERNEL);
-	if (!press_data->buffer_data)
-		return -ENOMEM;
-
 	err = iio_triggered_buffer_postenable(indio_dev);
 	if (err < 0)
-		goto st_press_free_buffer;
+		return err;
 
 	err = st_sensors_set_enable(indio_dev, true);
 	if (err < 0)
@@ -51,14 +45,11 @@ static int st_press_buffer_postenable(struct iio_dev *indio_dev)
 
 st_press_buffer_predisable:
 	iio_triggered_buffer_predisable(indio_dev);
-st_press_free_buffer:
-	kfree(press_data->buffer_data);
 	return err;
 }
 
 static int st_press_buffer_predisable(struct iio_dev *indio_dev)
 {
-	struct st_sensor_data *press_data = iio_priv(indio_dev);
 	int err, err2;
 
 	err = st_sensors_set_enable(indio_dev, false);
@@ -67,7 +58,6 @@ static int st_press_buffer_predisable(struct iio_dev *indio_dev)
 	if (!err)
 		err = err2;
 
-	kfree(press_data->buffer_data);
 	return err;
 }