Hi, I am looking at struct iio_dev in include/linux/iio/iio.h and the active_scan_mask member is documented as: @active_scan_mask: [INTERN] union of all scan masks requested by buffers I believe that this is a bitmap where if bit X is set, that means the channel with scan_index == X is enabled for buffering. I believe that "[INTERN]" means that this member should not be accessed by a device driver, but I see many device drivers iterating over the bits of this field. Is my understanding incorrect? Perhaps "[INTERN]" means that the field can be read from the driver, but should not be written. Please help me clear up my understanding. Thanks, David