[PATCH v2 2/2] Input: touchscreen-iproc: add device tree bindings
Jonathan Richardson
jonathar at broadcom.com
Fri Dec 19 14:17:50 PST 2014
Documents the touchscreen device tree binding for Broadcom iProc family
of SoCs.
Reviewed-by: Scott Branden <sbranden at broadcom.com>
Tested-by: Scott Branden <sbranden at broadcom.com>
Signed-off-by: Jonathan Richardson <jonathar at broadcom.com>
---
.../input/touchscreen/brcm,iproc-touchscreen.txt | 70 ++++++++++++++++++++
1 file changed, 70 insertions(+)
create mode 100644 Documentation/devicetree/bindings/input/touchscreen/brcm,iproc-touchscreen.txt
diff --git a/Documentation/devicetree/bindings/input/touchscreen/brcm,iproc-touchscreen.txt b/Documentation/devicetree/bindings/input/touchscreen/brcm,iproc-touchscreen.txt
new file mode 100644
index 0000000..eb28822
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/brcm,iproc-touchscreen.txt
@@ -0,0 +1,70 @@
+* Broadcom's IPROC Touchscreen Controller
+
+Required properties:
+- compatible: must be "brcm,iproc-touchscreen"
+- reg: physical base address of the controller and length of memory mapped
+ region.
+- clocks: The clock provided by the SOC to driver the tsc
+- clock-name: name for the clock
+- interrupts: The touchscreen controller's interrupt
+
+Optional properties:
+- scanning_period: Time between scans. Each step is 1024 us. Valid 1-256.
+- debounce_timeout: Each step is 512 us. Valid 0-255
+- settling_timeout: The settling duration (in ms) is the amount of time
+ the tsc waits to allow the voltage to settle after
+ turning on the drivers in detection mode.
+ Valid values: 0-11
+ 0 = 0.008 ms
+ 1 = 0.01 ms
+ 2 = 0.02 ms
+ 3 = 0.04 ms
+ 4 = 0.08 ms
+ 5 = 0.16 ms
+ 6 = 0.32 ms
+ 7 = 0.64 ms
+ 8 = 1.28 ms
+ 9 = 2.56 ms
+ 10 = 5.12 ms
+ 11 = 10.24 ms
+- touch_timeout: The continuous number of scan periods in which touch is
+ not detected before the controller returns to idle state.
+ Valid values 0-255.
+- average_data: Number of data samples which are averaged before a final
+ data point is placed into the FIFO
+ Valid values 0-7
+ 0 = 1 sample
+ 1 = 2 samples
+ 2 = 4 samples
+ 3 = 8 samples
+ 4 = 16 samples
+ 5 = 32 samples
+ 6 = 64 samples
+ 7 = 128 samples
+- fifo_threshold: Interrupt is generated whenever the number of fifo
+ entries exceeds this value
+ Valid values 0-31
+- ts-rotation: Touch screen controller and display panel orientation angle.
+ 0 = Tsc x_min y_min placed at LCD x_min y_min. None
+ 1 = Tsc x_min y_max placed at LCD x_min y_min. 90 degrees
+ 2 = Tsc x_max y_max placed at LCD x_min y_min. 180 degrees
+ 3 = Tsc x_max y_min placed at LCD x_min y_min. 270 degrees
+Example:
+
+ touchscreen: tsc at 0x180A6000 {
+ compatible = "brcm,iproc-touchscreen";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ reg = <0x180A6000 0x40>;
+ clocks = <&adc_clk>;
+ clock-names = "tsc_clk";
+ interrupts = <GIC_SPI 164 IRQ_TYPE_LEVEL_HIGH>;
+
+ scanning_period = <5>;
+ debounce_timeout = <40>;
+ settling_timeout = <7>;
+ touch_timeout = <10>;
+ average_data = <5>;
+ fifo_threshold = <1>;
+ ts-rotation = <2>;
+ };
--
1.7.9.5
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