[PATCH 06/15] arm64: dts: qcom: msm8916-samsung-serranove: Add NFC

[Stephan Gerhold]

The LTE version of the S4 Mini VE has a NXP PN547, which is supported
by the nxp-nci-i2c driver in mainline. It seems to detect NFC tags
using "nfctool" just fine, although more testing is difficult given
there seem to be very few useful applications making use of the
Linux NFC subsystem. :(

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

Signed-off-by: Stephan Gerhold <stephan at gerhold.net>
---
 .../dts/qcom/msm8916-samsung-serranove.dts    | 50 +++++++++++++++++++
 1 file changed, 50 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/msm8916-samsung-serranove.dts b/arch/arm64/boot/dts/qcom/msm8916-samsung-serranove.dts
index 4a94158e7624..caeed942a4c5 100644
--- a/arch/arm64/boot/dts/qcom/msm8916-samsung-serranove.dts
+++ b/arch/arm64/boot/dts/qcom/msm8916-samsung-serranove.dts
@@ -168,6 +168,32 @@ touchkey at 20 {
 			pinctrl-0 = <&tkey_default>;
 		};
 	};
+
+	i2c-nfc {
+		compatible = "i2c-gpio";
+		sda-gpios = <&msmgpio 0 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
+		scl-gpios = <&msmgpio 1 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&nfc_i2c_default>;
+
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		nfc at 2b {
+			compatible = "nxp,pn547", "nxp,nxp-nci-i2c";
+			reg = <0x2b>;
+
+			interrupt-parent = <&msmgpio>;
+			interrupts = <21 IRQ_TYPE_EDGE_RISING>;
+
+			enable-gpios = <&msmgpio 20 GPIO_ACTIVE_HIGH>;
+			firmware-gpios = <&msmgpio 49 GPIO_ACTIVE_HIGH>;
+
+			pinctrl-names = "default";
+			pinctrl-0 = <&nfc_default>;
+		};
+	};
 };
 
 &blsp_i2c2 {
@@ -434,6 +460,30 @@ muic_irq_default: muic-irq-default {
 		bias-disable;
 	};
 
+	nfc_default: nfc-default {
+		pins = "gpio20", "gpio49";
+		function = "gpio";
+
+		drive-strength = <2>;
+		bias-disable;
+
+		irq {
+			pins = "gpio21";
+			function = "gpio";
+
+			drive-strength = <2>;
+			bias-pull-down;
+		};
+	};
+
+	nfc_i2c_default: nfc-i2c-default {
+		pins = "gpio0", "gpio1";
+		function = "gpio";
+
+		drive-strength = <2>;
+		bias-disable;
+	};
+
 	tkey_default: tkey-default {
 		pins = "gpio98";
 		function = "gpio";
-- 
2.33.0