X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=Documentation%2Fdevicetree%2Fbindings%2Finput%2Ftouchscreen%2Fti-tsc-adc.txt;h=6c4fb34823d3e61cd6fda401b7b8becf9be95e33;hb=5c2770079fb9b8c5bfb7113d9e76de66e77a0e24;hp=878549ba814d5d1684ff2b5a960bc1725854e3f2;hpb=f4bcd8ccddb02833340652e9f46f5127828eb79d;p=pandora-kernel.git diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt index 878549ba814d..6c4fb34823d3 100644 --- a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt +++ b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt @@ -28,6 +28,20 @@ Required properties: ti,adc-channels: List of analog inputs available for ADC. AIN0 = 0, AIN1 = 1 and so on till AIN7 = 7. +Optional properties: +- child "tsc" + ti,charge-delay: Length of touch screen charge delay step in terms of + ADC clock cycles. Charge delay value should be large + in order to avoid false pen-up events. This value + effects the overall sampling speed, hence need to be + kept as low as possible, while avoiding false pen-up + event. Start from a lower value, say 0x400, and + increase value until false pen-up events are avoided. + The pen-up detection happens immediately after the + charge step, so this does in fact function as a + hardware knob for adjusting the amount of "settling + time". + Example: tscadc: tscadc@44e0d000 { compatible = "ti,am3359-tscadc"; @@ -36,6 +50,7 @@ Example: ti,x-plate-resistance = <200>; ti,coordiante-readouts = <5>; ti,wire-config = <0x00 0x11 0x22 0x33>; + ti,charge-delay = <0x400>; }; adc {