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authorVipul Kumar Samar <vipulkumar.samar@st.com>2012-11-22 23:42:12 -0800
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2012-11-22 23:47:09 -0800
commit037db524a2015607031c70a7935153120601b908 (patch)
tree82387672d07b8fb9d1fcd0098692256de20895cd /Documentation
parentedbe265d245b0fe05c43e96e52554dacae5dcc70 (diff)
downloadop-kernel-dev-037db524a2015607031c70a7935153120601b908.zip
op-kernel-dev-037db524a2015607031c70a7935153120601b908.tar.gz
Input: stmpe-ts - add DT support for stmpe touchscreen
This patch allows the STMPE Touchscreen driver to be successfully probed and initialised when Device Tree support is enabled. Bindings are mentioned in Documentation too. Signed-off-by: Vipul Kumar Samar <vipulkumar.samar@st.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/input/touchscreen/stmpe.txt43
1 files changed, 43 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt b/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt
new file mode 100644
index 0000000..127baa3
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt
@@ -0,0 +1,43 @@
+STMPE Touchscreen
+----------------
+
+Required properties:
+ - compatible: "st,stmpe-ts"
+
+Optional properties:
+- st,sample-time: ADC converstion time in number of clock. (0 -> 36 clocks, 1 ->
+ 44 clocks, 2 -> 56 clocks, 3 -> 64 clocks, 4 -> 80 clocks, 5 -> 96 clocks, 6
+ -> 144 clocks), recommended is 4.
+- st,mod-12b: ADC Bit mode (0 -> 10bit ADC, 1 -> 12bit ADC)
+- st,ref-sel: ADC reference source (0 -> internal reference, 1 -> external
+ reference)
+- st,adc-freq: ADC Clock speed (0 -> 1.625 MHz, 1 -> 3.25 MHz, 2 || 3 -> 6.5 MHz)
+- st,ave-ctrl: Sample average control (0 -> 1 sample, 1 -> 2 samples, 2 -> 4
+ samples, 3 -> 8 samples)
+- st,touch-det-delay: Touch detect interrupt delay (0 -> 10 us, 1 -> 50 us, 2 ->
+ 100 us, 3 -> 500 us, 4-> 1 ms, 5 -> 5 ms, 6 -> 10 ms, 7 -> 50 ms) recommended
+ is 3
+- st,settling: Panel driver settling time (0 -> 10 us, 1 -> 100 us, 2 -> 500 us, 3
+ -> 1 ms, 4 -> 5 ms, 5 -> 10 ms, 6 for 50 ms, 7 -> 100 ms) recommended is 2
+- st,fraction-z: Length of the fractional part in z (fraction-z ([0..7]) = Count of
+ the fractional part) recommended is 7
+- st,i-drive: current limit value of the touchscreen drivers (0 -> 20 mA typical 35
+ mA max, 1 -> 50 mA typical 80 mA max)
+
+Node name must be stmpe_touchscreen and should be child node of stmpe node to
+which it belongs.
+
+Example:
+
+ stmpe_touchscreen {
+ compatible = "st,stmpe-ts";
+ st,sample-time = <4>;
+ st,mod-12b = <1>;
+ st,ref-sel = <0>;
+ st,adc-freq = <1>;
+ st,ave-ctrl = <1>;
+ st,touch-det-delay = <2>;
+ st,settling = <2>;
+ st,fraction-z = <7>;
+ st,i-drive = <1>;
+ };
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