// SPDX-License-Identifier: (GPL-2.0-or-later OR MIT)
/*
 * Copyright (c) 2024 Cherry Embedded Solutions GmbH
 *
 * Device Tree Overlay for the Pre-ICT tester adapter for the Mezzanine
 * connector on RK3588 Jaguar.
 *
 * This adapter has a PCIe Gen2 x1 M.2 M-Key connector and two proprietary
 * camera connectors (each their own I2C bus, clock, reset and PWM lines as well
 * as 2-lane CSI).
 *
 * This adapter routes some GPIOs to power rails and loops together some other
 * GPIOs.
 *
 * This adapter is used during manufacturing for validating proper soldering of
 * the mezzanine connector.
 */

/dts-v1/;
/plugin/;

#include <dt-bindings/gpio/gpio.h>
#include <dt-bindings/pinctrl/rockchip.h>

&{/} {
	pre_ict_tester_vcc_1v2: regulator-pre-ict-tester-vcc-1v2 {
		compatible = "regulator-fixed";
		regulator-name = "pre_ict_tester_vcc_1v2";
		regulator-always-on;
		regulator-boot-on;
		regulator-min-microvolt = <1200000>;
		regulator-max-microvolt = <1200000>;
		vin-supply = <&vcc_3v3_s3>;
	};

	pre_ict_tester_vcc_2v8: regulator-pre-ict-tester-vcc-2v8 {
		compatible = "regulator-fixed";
		regulator-name = "pre_ict_tester_vcc_2v8";
		regulator-always-on;
		regulator-boot-on;
		regulator-min-microvolt = <2800000>;
		regulator-max-microvolt = <2800000>;
		vin-supply = <&vcc_3v3_s3>;
	};
};

&combphy0_ps {
	status = "okay";
};

&gpio3 {
	pinctrl-0 = <&pre_ict_pwr2gpio>;
	pinctrl-names = "default";
};

&pcie2x1l2 {
	pinctrl-names = "default";
	pinctrl-0 = <&pcie2x1l2_perstn_m0>;
	reset-gpios = <&gpio3 RK_PD1 GPIO_ACTIVE_HIGH>; /* PCIE20X1_2_PERSTN_M0 */
	vpcie3v3-supply = <&vcc_3v3_s3>;
	status = "okay";
};

&pinctrl {
	pcie2x1l2 {
		pcie2x1l2_perstn_m0: pcie2x1l2-perstn-m0 {
			rockchip,pins = <3 RK_PD1 RK_FUNC_GPIO &pcfg_pull_none>;
		};
	};

	pre-ict-tester {
		pre_ict_pwr2gpio: pre-ict-pwr2gpio-pins {
			rockchip,pins =
			/*
			 * GPIO3_A3 requires two power rails to be properly
			 * routed to the mezzanine connector to report a proper
			 * value: VCC_1V8_S0_1 and VCC_IN_2. It may report an
			 * incorrect value if VCC_1V8_S0_1 isn't properly routed,
			 * but GPIO3_C6 would catch this HW soldering issue.
			 * If VCC_IN_2 is properly routed, GPIO3_A3 should be
			 * LOW. The signal shall not read HIGH in the event
			 * GPIO3_A3 isn't properly routed due to soldering
			 * issue. Therefore, let's enforce a pull-up (which is
			 * the SoC default for this pin).
			 */
				<3 RK_PA3 RK_FUNC_GPIO &pcfg_pull_up>,
			/*
			 * GPIO3_A4 is directly routed to VCC_1V8_S0_2 power
			 * rail. It should be HIGH if all is properly soldered.
			 * To guarantee that, a pull-down is enforced (which is
			 * the SoC default for this pin) so that LOW is read if
			 * the loop doesn't exist on HW (soldering issue on
			 * either signals).
			 */
				<3 RK_PA4 RK_FUNC_GPIO &pcfg_pull_down>,
			/*
			 * GPIO3_B2 requires two power rails to be properly
			 * routed to the mezzanine connector to report a proper
			 * value: VCC_1V8_S0_1 and VCC_IN_1. It may report an
			 * incorrect value if VCC_1V8_S0_1 isn't properly routed,
			 * but GPIO3_C6 would catch this HW soldering issue.
			 * If VCC_IN_1 is properly routed, GPIO3_B2 should be
			 * LOW. This is an issue if GPIO3_B2 isn't properly
			 * routed due to soldering issue, because GPIO3_B2
			 * default bias is pull-down therefore being LOW. So
			 * the worst case scenario and the pass scenario expect
			 * the same value. Make GPIO3_B2 a pull-up so that a
			 * soldering issue on GPIO3_B2 reports HIGH but proper
			 * soldering reports LOW.
			 */
				<3 RK_PB2 RK_FUNC_GPIO &pcfg_pull_up>,
			/*
			 * GPIO3_C6 is directly routed to VCC_1V8_S0_1 power
			 * rail. It should be HIGH if all is properly soldered.
			 * This is an issue if GPIO3_C6 or VCC_1V8_S0_1 isn't
			 * properly routed due to soldering issue, because
			 * GPIO3_C6 default bias is pull-up therefore being HIGH
			 * in all cases:
			 *  - GPIO3_C6 is floating (so HIGH) if GPIO3_C6 is not
			 *    routed properly,
			 *  - GPIO3_C6 is floating (so HIGH) if VCC_1V8_S0_1 is
			 *    not routed properly,
			 *  - GPIO3_C6 is HIGH if everything is proper,
			 * Make GPIO3_C6 a pull-down so that a soldering issue
			 * on GPIO3_C6 or VCC_1V8_S0_1 reports LOW but proper
			 * soldering reports HIGH.
			 */
				<3 RK_PC6 RK_FUNC_GPIO &pcfg_pull_down>,
			/*
			 * GPIO3_D2 is routed to VCC_5V0_1 power rail through a
			 * voltage divider on the adapter.
			 * It should be HIGH if all is properly soldered.
			 * To guarantee that, a pull-down is enforced (which is
			 * the SoC default for this pin) so that LOW is read if
			 * the loop doesn't exist on HW (soldering issue on
			 * either signals).
			 */
				<3 RK_PD2 RK_FUNC_GPIO &pcfg_pull_down>,
			/*
			 * GPIO3_D3 is routed to VCC_5V0_2 power rail through a
			 * voltage divider on the adapter.
			 * It should be HIGH if all is properly soldered.
			 * To guarantee that, a pull-down is enforced (which is
			 * the SoC default for this pin) so that LOW is read if
			 * the loop doesn't exist on HW (soldering issue on
			 * either signals).
			 */
				<3 RK_PD3 RK_FUNC_GPIO &pcfg_pull_down>,
			/*
			 * GPIO3_D4 is routed to VCC_3V3_S3_1 power rail through
			 * a voltage divider on the adapter.
			 * It should be HIGH if all is properly soldered.
			 * To guarantee that, a pull-down is enforced (which is
			 * the SoC default for this pin) so that LOW is read if
			 * the loop doesn't exist on HW (soldering issue on
			 * either signals).
			 */
				<3 RK_PD4 RK_FUNC_GPIO &pcfg_pull_down>,
			/*
			 * GPIO3_D5 is routed to VCC_3V3_S3_2 power rail through
			 * a voltage divider on the adapter.
			 * It should be HIGH if all is properly soldered.
			 * To guarantee that, a pull-down is enforced (which is
			 * the SoC default for this pin) so that LOW is read if
			 * the loop doesn't exist on HW (soldering issue on
			 * either signals).
			 */
				<3 RK_PD5 RK_FUNC_GPIO &pcfg_pull_down>;
		};
	};
};