1*4882a593SmuzhiyunBindings for ADC envelope detector using a DAC and a comparator 2*4882a593Smuzhiyun 3*4882a593SmuzhiyunThe DAC is used to find the peak level of an alternating voltage input 4*4882a593Smuzhiyunsignal by a binary search using the output of a comparator wired to 5*4882a593Smuzhiyunan interrupt pin. Like so: 6*4882a593Smuzhiyun _ 7*4882a593Smuzhiyun | \ 8*4882a593Smuzhiyun input +------>-------|+ \ 9*4882a593Smuzhiyun | \ 10*4882a593Smuzhiyun .-------. | }---. 11*4882a593Smuzhiyun | | | / | 12*4882a593Smuzhiyun | dac|-->--|- / | 13*4882a593Smuzhiyun | | |_/ | 14*4882a593Smuzhiyun | | | 15*4882a593Smuzhiyun | | | 16*4882a593Smuzhiyun | irq|------<-------' 17*4882a593Smuzhiyun | | 18*4882a593Smuzhiyun '-------' 19*4882a593Smuzhiyun 20*4882a593SmuzhiyunRequired properties: 21*4882a593Smuzhiyun- compatible: Should be "axentia,tse850-envelope-detector" 22*4882a593Smuzhiyun- io-channels: Channel node of the dac to be used for comparator input. 23*4882a593Smuzhiyun- io-channel-names: Should be "dac". 24*4882a593Smuzhiyun- interrupt specification for one client interrupt, 25*4882a593Smuzhiyun see ../../interrupt-controller/interrupts.txt for details. 26*4882a593Smuzhiyun- interrupt-names: Should be "comp". 27*4882a593Smuzhiyun 28*4882a593SmuzhiyunExample: 29*4882a593Smuzhiyun 30*4882a593Smuzhiyun &i2c { 31*4882a593Smuzhiyun dpot: mcp4651-104@28 { 32*4882a593Smuzhiyun compatible = "microchip,mcp4651-104"; 33*4882a593Smuzhiyun reg = <0x28>; 34*4882a593Smuzhiyun #io-channel-cells = <1>; 35*4882a593Smuzhiyun }; 36*4882a593Smuzhiyun }; 37*4882a593Smuzhiyun 38*4882a593Smuzhiyun dac: dac { 39*4882a593Smuzhiyun compatible = "dpot-dac"; 40*4882a593Smuzhiyun vref-supply = <®_3v3>; 41*4882a593Smuzhiyun io-channels = <&dpot 0>; 42*4882a593Smuzhiyun io-channel-names = "dpot"; 43*4882a593Smuzhiyun #io-channel-cells = <1>; 44*4882a593Smuzhiyun }; 45*4882a593Smuzhiyun 46*4882a593Smuzhiyun envelope-detector { 47*4882a593Smuzhiyun compatible = "axentia,tse850-envelope-detector"; 48*4882a593Smuzhiyun io-channels = <&dac 0>; 49*4882a593Smuzhiyun io-channel-names = "dac"; 50*4882a593Smuzhiyun 51*4882a593Smuzhiyun interrupt-parent = <&gpio>; 52*4882a593Smuzhiyun interrupts = <3 IRQ_TYPE_EDGE_FALLING>; 53*4882a593Smuzhiyun interrupt-names = "comp"; 54*4882a593Smuzhiyun }; 55