iio: fix drivers that check buffer->scan_mask

If the in-kernel push interface is used we may have a different masks
on the device buffer and the kernel buffer and in this case the device
should generate data for the reunion of the buffers, which is
available at indio_dev->active_scan_mask.

Compiled tested only except for bmc150-accel which was tested at
runtime with the hardware.

Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index 2e5cc44..a0e7161 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -188,12 +188,11 @@
 static int tiadc_buffer_postenable(struct iio_dev *indio_dev)
 {
 	struct tiadc_device *adc_dev = iio_priv(indio_dev);
-	struct iio_buffer *buffer = indio_dev->buffer;
 	unsigned int enb = 0;
 	u8 bit;
 
 	tiadc_step_config(indio_dev);
-	for_each_set_bit(bit, buffer->scan_mask, adc_dev->channels)
+	for_each_set_bit(bit, indio_dev->active_scan_mask, adc_dev->channels)
 		enb |= (get_adc_step_bit(adc_dev, bit) << 1);
 	adc_dev->buffer_en_ch_steps = enb;