xref: /linux/Documentation/ABI/testing/sysfs-bus-iio-light-isl29018 (revision 71e2f4dd5a65bd8dbca0b77661e75eea471168f8)
1What:		/sys/bus/iio/devices/iio:deviceX/proximity_on_chip_ambient_infrared_suppression
2Date:		January 2011
3KernelVersion:	2.6.37
4Contact:	linux-iio@vger.kernel.org
5Description:
6		From ISL29018 Data Sheet (FN6619.4, Oct 8, 2012) regarding the
7		infrared suppression:
8
9		Scheme 0, makes full n (4, 8, 12, 16) bits (unsigned) proximity
10		detection. The range of Scheme 0 proximity count is from 0 to
11		2^n. Logic 1 of this bit, Scheme 1, makes n-1 (3, 7, 11, 15)
12		bits (2's complementary) proximity_less_ambient detection. The
13		range of Scheme 1 proximity count is from -2^(n-1) to 2^(n-1).
14		The sign bit is extended for resolutions less than 16. While
15		Scheme 0 has wider dynamic range, Scheme 1 proximity detection
16		is less affected by the ambient IR noise variation.
17
18		0 Sensing IR from LED and ambient
19		1 Sensing IR from LED with ambient IR rejection
20