From:   Christian Hewitt <christianshewitt@gmail.com>
To:     Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Kevin Hilman <khilman@baylibre.com>,
        Jerome Brunet <jbrunet@baylibre.com>,
        Martin Blumenstingl <martin.blumenstingl@googlemail.com>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-amlogic@lists.infradead.org, linux-kernel@vger.kernel.org
Cc:     Christian Hewitt <christianshewitt@gmail.com>
Subject: [PATCH 1/4] arm64: dts: meson: bananapi-m5: switch VDDIO_C pin to OPEN_DRAIN
Date:   Fri, 27 Jan 2023 10:02:33 +0000
Message-Id: <20230127100236.3385154-2-christianshewitt@gmail.com>
In-Reply-To: <20230127100236.3385154-1-christianshewitt@gmail.com>
References: <20230127100236.3385154-1-christianshewitt@gmail.com>
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For proper warm (re)boot from SD card the BPI-M5 board requires TFLASH_VDD_EN
and VDDIO_C pins to be switched to high impedance mode. This can be achieved
using OPEN_DRAIN instead of ACTIVE_HIGH to leave the GPIO pins in input mode
and retain high state (pin has the pull-up).

This change is inspired by meson-sm1-odroid.dtsi where OPEN_DRAIN has been
used to resolve similar problems with the Odroid C4 board (TF_IO in the C4
dts is the equivalent regulator).

Fixes 976e920183e4 ("arm64: dts: meson-sm1: add Banana PI BPI-M5 board dts")
Suggested-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Christian Hewitt <christianshewitt@gmail.com>
---
 arch/arm64/boot/dts/amlogic/meson-sm1-bananapi-m5.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/amlogic/meson-sm1-bananapi-m5.dts b/arch/arm64/boot/dts/amlogic/meson-sm1-bananapi-m5.dts
index 028220ed45ad..3c1267a7ffef 100644
--- a/arch/arm64/boot/dts/amlogic/meson-sm1-bananapi-m5.dts
+++ b/arch/arm64/boot/dts/amlogic/meson-sm1-bananapi-m5.dts
@@ -123,7 +123,7 @@ vddio_c: regulator-vddio_c {
 		regulator-min-microvolt = <1800000>;
 		regulator-max-microvolt = <3300000>;
 
-		enable-gpio = <&gpio_ao GPIOE_2 GPIO_ACTIVE_HIGH>;
+		enable-gpio = <&gpio_ao GPIOE_2 GPIO_OPEN_DRAIN>;
 		enable-active-high;
 		regulator-always-on;
 
-- 
2.34.1