[PATCH v2 06/15] arm64: dts: qcom: msm8916-samsung-serranove: Add NFC

From: Stephan Gerhold <stephan@gerhold.net>
To: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Andy Gross <agross@kernel.org>,
	linux-arm-msm@vger.kernel.org, Rob Herring <robh+dt@kernel.org>,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	~postmarketos/upstreaming@lists.sr.ht,
	phone-devel@vger.kernel.org,
	Stephan Gerhold <stephan@gerhold.net>
Subject: [PATCH v2 06/15] arm64: dts: qcom: msm8916-samsung-serranove: Add NFC
Date: Mon,  4 Oct 2021 22:19:12 +0200	[thread overview]
Message-ID: <20211004201921.18526-7-stephan@gerhold.net> (raw)
In-Reply-To: <20211004201921.18526-1-stephan@gerhold.net>

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@gerhold.net>
---
Changes in v2: None.
---
 .../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 3ef00bdc043e..a78f87a5bf4f 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@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@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

