diff mbox series

[1/5] arm64: dts: qcom: msm8916-samsung-a2015: Add touch key

Message ID 20210604172742.10593-1-stephan@gerhold.net
State Accepted
Commit 61f363a625fcbff93171a271b898fcf37dd367c3
Headers show
Series [1/5] arm64: dts: qcom: msm8916-samsung-a2015: Add touch key | expand

Commit Message

Stephan Gerhold June 4, 2021, 5:27 p.m. UTC
The Samsung Galaxy A3/A5 both have two capacitive touch keys,
connected to an ABOV MCU. It implements the same interface as
implemented by the tm2-touchkey driver and works just fine with
the coreriver,tc360-touchkey compatible. It's probably actually some
Samsung-specific interface that they implement with different MCUs.

Note that for some reason Samsung decided to connect this to GPIOs
where no hardware I2C bus is available, so we need to fall back
to software bit-banging using i2c-gpio.

The vdd/vcc-supply is board-specific and will be added separately
for a3u/a5u.

Co-developed-by: Michael Srba <Michael.Srba@seznam.cz>
Signed-off-by: Michael Srba <Michael.Srba@seznam.cz>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---
 .../qcom/msm8916-samsung-a2015-common.dtsi    | 45 +++++++++++++++++++
 1 file changed, 45 insertions(+)
diff mbox series

Patch

diff --git a/arch/arm64/boot/dts/qcom/msm8916-samsung-a2015-common.dtsi b/arch/arm64/boot/dts/qcom/msm8916-samsung-a2015-common.dtsi
index 230ba3ce3277..3c77e7ef9eda 100644
--- a/arch/arm64/boot/dts/qcom/msm8916-samsung-a2015-common.dtsi
+++ b/arch/arm64/boot/dts/qcom/msm8916-samsung-a2015-common.dtsi
@@ -95,6 +95,35 @@  muic: extcon@25 {
 			pinctrl-0 = <&muic_int_default>;
 		};
 	};
+
+	i2c-tkey {
+		compatible = "i2c-gpio";
+		sda-gpios = <&msmgpio 16 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
+		scl-gpios = <&msmgpio 17 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&tkey_i2c_default>;
+
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		touchkey: touchkey@20 {
+			/* Note: Actually an ABOV MCU that implements same interface */
+			compatible = "coreriver,tc360-touchkey";
+			reg = <0x20>;
+
+			interrupt-parent = <&msmgpio>;
+			interrupts = <98 IRQ_TYPE_EDGE_FALLING>;
+
+			/* vcc/vdd-supply are board-specific */
+			vddio-supply = <&pm8916_l6>;
+
+			linux,keycodes = <KEY_APPSELECT KEY_BACK>;
+
+			pinctrl-names = "default";
+			pinctrl-0 = <&tkey_default>;
+		};
+	};
 };
 
 &blsp_i2c2 {
@@ -333,6 +362,22 @@  muic_int_default: muic-int-default {
 		bias-disable;
 	};
 
+	tkey_default: tkey-default {
+		pins = "gpio98";
+		function = "gpio";
+
+		drive-strength = <2>;
+		bias-disable;
+	};
+
+	tkey_i2c_default: tkey-i2c-default {
+		pins = "gpio16", "gpio17";
+		function = "gpio";
+
+		drive-strength = <2>;
+		bias-disable;
+	};
+
 	tsp_en_default: tsp-en-default {
 		pins = "gpio73";
 		function = "gpio";