[PATCH 5/5] arm64: dts: rockchip: fix USB OTG power on Photonicat in battery mode

[Coia Prant <coiaprant@gmail.com>]

When the Ariaboard Photonicat runs on battery, the USB port has no power
output and attached devices are not detected. With the external supply
connected, the same port works fine. The root cause is that the
regulator feeding usb2phy0_otg (vcc5v0_usb30_otg0) is only available
from the external DC input, and there is no 5V rail for the USB PHY
when the board is powered from the battery.

Add a vcc5v0_usb30_otg0_boost regulator, gated by vcc5v0_usb30_otg0,
and switch usb2phy0_otg to use it as its phy-supply. The boost converter
is enabled through GPIO4_D2 and generates the 5V USB VBUS from the
vccin_5v rail. Note that vccin_5v is the actual energy source, while
vcc5v0_usb30_otg0 gates the path; vin-supply is modelled on the gate so
the regulator core enables it before the boost.

This restores USB host functionality on battery power, matching the
vendor firmware behaviour.

Link: https://github.com/immortalwrt/immortalwrt/issues/1534
Fixes: ba124e06ce7b ("arm64: dts: rockchip: add dts for Ariaboard Photonicat RK3568")
Cc: stable@vger.kernel.org
Signed-off-by: Coia Prant <coiaprant@gmail.com>
---
 .../boot/dts/rockchip/rk3568-photonicat.dts   | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/rockchip/rk3568-photonicat.dts b/arch/arm64/boot/dts/rockchip/rk3568-photonicat.dts
index 7e0a2ab829209..bcdfe76000c46 100644
--- a/arch/arm64/boot/dts/rockchip/rk3568-photonicat.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3568-photonicat.dts
@@ -151,6 +151,19 @@ vcc5v0_usb30_otg0: regulator-vcc5v0-usb30-otg0 {
 		vin-supply = <&vccin_5v>;
 	};
 
+	/* actually fed by vccin_5v, dependent on vcc5v0_usb30_otg0 */
+	vcc5v0_usb30_otg0_boost: regulator-vcc5v0-boost {
+		compatible = "regulator-fixed";
+		enable-active-high;
+		gpio = <&gpio4 RK_PD2 GPIO_ACTIVE_HIGH>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&vcc5v0_boost_en>;
+		regulator-name = "vcc5v0_boost";
+		regulator-min-microvolt = <5000000>;
+		regulator-max-microvolt = <5000000>;
+		vin-supply = <&vcc5v0_usb30_otg0>;
+	};
+
 	vccin_5v: regulator-vccin-5v {
 		compatible = "regulator-fixed";
 		regulator-name = "vccin_5v";
@@ -460,6 +473,10 @@ rf_pwr_en: rf-pwr-en {
 		usb_host_pwren_h: usb-host-pwren-h {
 			rockchip,pins = <0 RK_PA5 RK_FUNC_GPIO &pcfg_pull_none>;
 		};
+
+		vcc5v0_boost_en: vcc5v0-boost-en {
+			rockchip,pins = <4 RK_PD2 RK_FUNC_GPIO &pcfg_pull_none>;
+		};
 	};
 
 	wifi {
@@ -617,7 +634,7 @@ &usb2phy0_host {
 };
 
 &usb2phy0_otg {
-	phy-supply = <&vcc5v0_usb30_otg0>;
+	phy-supply = <&vcc5v0_usb30_otg0_boost>;
 	status = "okay";
 };
 
-- 
2.47.3