diff options
Diffstat (limited to 'Documentation/devicetree')
| -rw-r--r-- | Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt new file mode 100644 index 000000000000..491c97b78384 --- /dev/null +++ b/Documentation/devicetree/bindings/input/touchscreen/ti-tsc-adc.txt @@ -0,0 +1,44 @@ +* TI - TSC ADC (Touschscreen and analog digital converter) +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Required properties: +- child "tsc" + ti,wires: Wires refer to application modes i.e. 4/5/8 wire touchscreen + support on the platform. + ti,x-plate-resistance: X plate resistance + ti,coordiante-readouts: The sequencer supports a total of 16 + programmable steps each step is used to + read a single coordinate. A single + readout is enough but multiple reads can + increase the quality. + A value of 5 means, 5 reads for X, 5 for + Y and 2 for Z (always). This utilises 12 + of the 16 software steps available. The + remaining 4 can be used by the ADC. + ti,wire-config: Different boards could have a different order for + connecting wires on touchscreen. We need to provide an + 8 bit number where in the 1st four bits represent the + analog lines and the next 4 bits represent positive/ + negative terminal on that input line. Notations to + represent the input lines and terminals resoectively + is as follows: + AIN0 = 0, AIN1 = 1 and so on till AIN7 = 7. + XP = 0, XN = 1, YP = 2, YN = 3. +- child "adc" + ti,adc-channels: List of analog inputs available for ADC. + AIN0 = 0, AIN1 = 1 and so on till AIN7 = 7. + +Example: + tscadc: tscadc@44e0d000 { + compatible = "ti,am3359-tscadc"; + tsc { + ti,wires = <4>; + ti,x-plate-resistance = <200>; + ti,coordiante-readouts = <5>; + ti,wire-config = <0x00 0x11 0x22 0x33>; + }; + + adc { + ti,adc-channels = <4 5 6 7>; + }; + } |