Linux Device Drivers Development

IIO buffer sysfs interface

An IIO buffer has an associated attributes directory under /sys/bus/iio/iio:deviceX/buffer/*. Here are some of the existing attributes:

• length: The total number of data samples (capacity) that can be stored by the buffer. This is the number of scans contained by the buffer.
• enable: This activates buffer capture, starting the buffer capture.
• watermark: This attribute has been available since kernel version 4.2. It is a positive number that specifies how many scan elements a blocking read should wait for. If using poll for example, it will block until the watermark is reached. It makes sense only if the watermark is greater than the requested amount of reads. It does not affect non-blocking reads. You can block on ...