[PATCH] arm64: dts: qcom: msm8916-samsung-serranove: Add RT5033 PMIC with charger

[Jakob Hauser]

For the regulators, apply the same settings as in the downstream
devicetree [1], including the "regulator-always-on" for the SAFE_LDO.
For the voltage of SAFE_LDO, however, there is only one voltage of 4.9 V
available in the mainline driver [2][3].

The values of the battery data evolve from following sources:
- precharge current: 450 mA corresponds to the default value of the chip. It
  doesn't get changed by the downstream Android driver. Therefore let's stick
  to this value.
- constant charge current: The 1000 mA are taken from the downstream devicetree
  of the serranove battery. It's not easy to spot. The value is in the line
  "input_current_limit" [4]. The rows are according to the power supply type,
  the 4th value stands for "main supply" [5]. That's the value used by the
  Android driver when a charging cable is plugged into the device.
- charge termination current: In the downstream devicetree of the battery
  that's the line "full_check_current_1st", which contains the 150 mA [6].
- precharge voltage: This one doesn't get set in the downstream Android driver.
  The chip's default is 2.8 V. That seemed too low to have a notable effect of
  handling the battery gentle. The chosen value of 3.5 V is a bit arbitrary
  and possibly rather high. As the device is already several years old and
  therefore most batteries too, a value on the safe side seems reasonable.
- constant charge voltage: The value of 4.35 V is set in the line
  "chg_float_voltage" of the downstream battery devicetree [7].

The "connector" sub-node in the extcon node, the "battery" node in the
general section and the line "power-supplies" in the fuel-gauge node result
from the way of implementation documented in the dt-bindings of
rt5033-charger [8] and mfd rt5033 [9].

[1] https://github.com/msm8916-mainline/linux-downstream/blob/GT-I9195I/arch/arm/boot/dts/samsung/msm8916/msm8916-sec-serranovelte-eur-r03.dtsi#L135-L181
[2] https://github.com/torvalds/linux/blob/v6.3/include/linux/mfd/rt5033-private.h#L211-L212
[3] https://github.com/torvalds/linux/blob/v6.3/drivers/regulator/rt5033-regulator.c#L83
[4] https://github.com/msm8916-mainline/linux-downstream/blob/GT-I9195I/arch/arm/boot/dts/samsung/msm8916/msm8916-sec-serranovelte-battery-r01.dtsi#L100
[5] https://github.com/msm8916-mainline/linux-downstream/blob/GT-I9195I/include/linux/power_supply.h#L173-L177
[6] https://github.com/msm8916-mainline/linux-downstream/blob/GT-I9195I/arch/arm/boot/dts/samsung/msm8916/msm8916-sec-serranovelte-battery-r01.dtsi#L102
[7] https://github.com/msm8916-mainline/linux-downstream/blob/GT-I9195I/arch/arm/boot/dts/samsung/msm8916/msm8916-sec-serranovelte-battery-r01.dtsi#L95
[8] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/Documentation/devicetree/bindings/power/supply/richtek,rt5033-charger.yaml?h=next-20230616
[9] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/Documentation/devicetree/bindings/mfd/richtek,rt5033.yaml?h=next-20230616

Signed-off-by: Jakob Hauser <jahau@xxxxxxxxxxxxxx>
---
The patch is based on linux-next "next-20230616".

The driver rt5033-charger was just recently added to linux-next.

 .../dts/qcom/msm8916-samsung-serranove.dts    | 67 ++++++++++++++++++-
 1 file changed, 66 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/qcom/msm8916-samsung-serranove.dts b/arch/arm64/boot/dts/qcom/msm8916-samsung-serranove.dts
index 15dc246e84e2..2114d26548db 100644
--- a/arch/arm64/boot/dts/qcom/msm8916-samsung-serranove.dts
+++ b/arch/arm64/boot/dts/qcom/msm8916-samsung-serranove.dts
@@ -142,6 +142,12 @@ muic: extcon@14 {
 
 			pinctrl-names = "default";
 			pinctrl-0 = <&muic_irq_default>;
+
+			usb_con: connector {
+				compatible = "usb-b-connector";
+				label = "micro-USB";
+				type = "micro";
+			};
 		};
 	};
 
@@ -199,6 +205,15 @@ nfc@2b {
 			pinctrl-0 = <&nfc_default>;
 		};
 	};
+
+	battery: battery {
+		compatible = "simple-battery";
+		precharge-current-microamp = <450000>;
+		constant-charge-current-max-microamp = <1000000>;
+		charge-term-current-microamp = <150000>;
+		precharge-upper-limit-microvolt = <3500000>;
+		constant-charge-voltage-max-microvolt = <4350000>;
+	};
 };
 
 &blsp_i2c2 {
@@ -228,7 +243,7 @@ magnetometer@2e {
 &blsp_i2c4 {
 	status = "okay";
 
-	battery@35 {
+	fuel-gauge@35 {
 		compatible = "richtek,rt5033-battery";
 		reg = <0x35>;
 
@@ -237,6 +252,8 @@ battery@35 {
 
 		pinctrl-names = "default";
 		pinctrl-0 = <&fg_alert_default>;
+
+		power-supplies = <&rt5033_charger>;
 	};
 };
 
@@ -261,6 +278,46 @@ touchscreen@20 {
 	};
 };
 
+&blsp_i2c6 {
+	status = "okay";
+
+	pmic@34 {
+		compatible = "richtek,rt5033";
+		reg = <0x34>;
+
+		interrupt-parent = <&tlmm>;
+		interrupts = <62 IRQ_TYPE_EDGE_FALLING>;
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&pmic_int_default>;
+
+		regulators {
+			safe_ldo_reg: SAFE_LDO {
+				regulator-name = "SAFE_LDO";
+				regulator-min-microvolt = <4900000>;
+				regulator-max-microvolt = <4900000>;
+				regulator-always-on;
+			};
+			ldo_reg: LDO {
+				regulator-name = "LDO";
+				regulator-min-microvolt = <2800000>;
+				regulator-max-microvolt = <2800000>;
+			};
+			buck_reg: BUCK {
+				regulator-name = "BUCK";
+				regulator-min-microvolt = <1200000>;
+				regulator-max-microvolt = <1200000>;
+			};
+		};
+
+		rt5033_charger: charger {
+			compatible = "richtek,rt5033-charger";
+			monitored-battery = <&battery>;
+			richtek,usb-connector = <&usb_con>;
+		};
+	};
+};
+
 &blsp_uart2 {
 	status = "okay";
 };
@@ -387,6 +444,14 @@ nfc_i2c_default: nfc-i2c-default-state {
 		bias-disable;
 	};
 
+	pmic_int_default: pmic-int-default-state {
+		pins = "gpio62";
+		function = "gpio";
+
+		drive-strength = <2>;
+		bias-disable;
+	};
+
 	tkey_default: tkey-default-state {
 		pins = "gpio98";
 		function = "gpio";
-- 
2.39.2