1*4882a593SmuzhiyunWhat: /sys/bus/iio/devices/iio:deviceX/proximity_on_chip_ambient_infrared_suppression 2*4882a593SmuzhiyunDate: January 2011 3*4882a593SmuzhiyunKernelVersion: 2.6.37 4*4882a593SmuzhiyunContact: linux-iio@vger.kernel.org 5*4882a593SmuzhiyunDescription: 6*4882a593Smuzhiyun From ISL29018 Data Sheet (FN6619.4, Oct 8, 2012) regarding the 7*4882a593Smuzhiyun infrared suppression: 8*4882a593Smuzhiyun 9*4882a593Smuzhiyun Scheme 0, makes full n (4, 8, 12, 16) bits (unsigned) proximity 10*4882a593Smuzhiyun detection. The range of Scheme 0 proximity count is from 0 to 11*4882a593Smuzhiyun 2^n. Logic 1 of this bit, Scheme 1, makes n-1 (3, 7, 11, 15) 12*4882a593Smuzhiyun bits (2's complementary) proximity_less_ambient detection. The 13*4882a593Smuzhiyun range of Scheme 1 proximity count is from -2^(n-1) to 2^(n-1). 14*4882a593Smuzhiyun The sign bit is extended for resolutions less than 16. While 15*4882a593Smuzhiyun Scheme 0 has wider dynamic range, Scheme 1 proximity detection 16*4882a593Smuzhiyun is less affected by the ambient IR noise variation. 17*4882a593Smuzhiyun 18*4882a593Smuzhiyun == ============================================= 19*4882a593Smuzhiyun 0 Sensing IR from LED and ambient 20*4882a593Smuzhiyun 1 Sensing IR from LED with ambient IR rejection 21*4882a593Smuzhiyun == ============================================= 22