Input: tm2-touchkey - add touchkey driver support for TM2

This patch adds support for the TM2 touch key and led functionality.

The driver interfaces with userspace through an input device and reports
KEY_PHONE and KEY_BACK event types. LED brightness can be controlled by
"/sys/class/leds/tm2-touchkey/brightness".

Signed-off-by: Beomho Seo <beomho.seo@samsung.com>
Signed-off-by: Jaechul Lee <jcsing.lee@samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/input/cypress,tm2-touchkey.txt b/Documentation/devicetree/bindings/input/cypress,tm2-touchkey.txt
new file mode 100644
index 000000000000..635f62c756ee
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/cypress,tm2-touchkey.txt
@@ -0,0 +1,27 @@
+Samsung tm2-touchkey
+
+Required properties:
+- compatible: must be "cypress,tm2-touchkey"
+- reg: I2C address of the chip.
+- interrupt-parent: a phandle for the interrupt controller (see interrupt
+        binding[0]).
+- interrupts: interrupt to which the chip is connected (see interrupt
+        binding[0]).
+- vcc-supply : internal regulator output. 1.8V
+- vdd-supply : power supply for IC 3.3V
+
+[0]: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+
+Example:
+        &i2c0 {
+                /* ... */
+
+                touchkey@20 {
+                        compatible = "cypress,tm2-touchkey";
+                        reg = <0x20>;
+                        interrupt-parent = <&gpa3>;
+                        interrupts = <2 IRQ_TYPE_EDGE_FALLING>;
+                        vcc-supply=<&ldo32_reg>;
+                        vdd-supply=<&ldo33_reg>;
+                };
+        };