All machines of the Asurada platform have a touchscreen at address 0x10
in the I2C0 bus, but the devices vary: Spherion has the Elan eKTH3500
touchscreen, while Hayato has a generic HID-over-i2c touchscreen.

Add common support for the touchscreens on the platform and the
specifics in each board file.

Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---

 .../dts/mediatek/mt8192-asurada-hayato-r1.dts |  7 ++++++
 .../mediatek/mt8192-asurada-spherion-r0.dts   |  4 +++
 .../boot/dts/mediatek/mt8192-asurada.dtsi     | 25 +++++++++++++++++++
 3 files changed, 36 insertions(+)

diff --git a/arch/arm64/boot/dts/mediatek/mt8192-asurada-hayato-r1.dts b/arch/arm64/boot/dts/mediatek/mt8192-asurada-hayato-r1.dts
index e18e14b13d61..22d187df1428 100644
--- a/arch/arm64/boot/dts/mediatek/mt8192-asurada-hayato-r1.dts
+++ b/arch/arm64/boot/dts/mediatek/mt8192-asurada-hayato-r1.dts
@@ -9,3 +9,10 @@ / {
 	model = "MediaTek Hayato rev1";
 	compatible = "google,hayato-rev1", "google,hayato", "mediatek,mt8192";
 };
+
+&touchscreen {
+	compatible = "hid-over-i2c";
+	post-power-on-delay-ms = <10>;
+	hid-descr-addr = <0x0001>;
+	vdd-supply = <&pp3300_u>;
+};
diff --git a/arch/arm64/boot/dts/mediatek/mt8192-asurada-spherion-r0.dts b/arch/arm64/boot/dts/mediatek/mt8192-asurada-spherion-r0.dts
index b5372ce6bd95..20ae4a869c63 100644
--- a/arch/arm64/boot/dts/mediatek/mt8192-asurada-spherion-r0.dts
+++ b/arch/arm64/boot/dts/mediatek/mt8192-asurada-spherion-r0.dts
@@ -11,3 +11,7 @@ / {
 		     "google,spherion-rev1", "google,spherion-rev0",
 		     "google,spherion", "mediatek,mt8192";
 };
+
+&touchscreen {
+	compatible = "elan,ekth3500";
+};
diff --git a/arch/arm64/boot/dts/mediatek/mt8192-asurada.dtsi b/arch/arm64/boot/dts/mediatek/mt8192-asurada.dtsi
index b911f4fc3038..6e5c2f8fd591 100644
--- a/arch/arm64/boot/dts/mediatek/mt8192-asurada.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt8192-asurada.dtsi
@@ -92,6 +92,13 @@ &i2c0 {
 	clock-frequency = <400000>;
 	pinctrl-names = "default";
 	pinctrl-0 = <&i2c0_pins>;
+
+	touchscreen: touchscreen@10 {
+		reg = <0x10>;
+		interrupts-extended = <&pio 21 IRQ_TYPE_LEVEL_LOW>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&touchscreen_pins>;
+	};
 };
 
 &i2c1 {
@@ -458,6 +465,24 @@ pins-int-n {
 			mediatek,pull-up-adv = <3>;
 		};
 	};
+
+	touchscreen_pins: touchscreen-default-pins {
+		pins-irq {
+			pinmux = <PINMUX_GPIO21__FUNC_GPIO21>;
+			input-enable;
+			bias-pull-up;
+		};
+
+		pins-reset {
+			pinmux = <PINMUX_GPIO137__FUNC_GPIO137>;
+			output-high;
+		};
+
+		pins-report-sw {
+			pinmux = <PINMUX_GPIO138__FUNC_GPIO138>;
+			output-low;
+		};
+	};
 };
 
 &spi1 {
-- 
2.35.1