Merge tag 'mfd-for-linus-3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd

[pandora-kernel.git] / Documentation / devicetree / bindings / input / touchscreen / ti-tsc-adc.txt

diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt
index 878549b..6c4fb34 100644 (file)
--- 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 {