[PATCH] ARM: dts: imx6q-logicpd: Fix 3.3V regulator on SDHC1

From: Adam Ford
Date: Tue Oct 01 2019 - 20:37:45 EST


NVCC_SD1 is driven by a selector which chooses between 3.3V and
1.8. Currently, this is pulled down by a 10k resistor, but
occasionally, voltage spikes on this rail cause the regulator to
jump between 1.8 and 3.3V.

This patch explicitly sets GPIO_19 to choose the 3.3V rail by
forcing this IO pin low to stabilize NVCC_SD1.

Signed-off-by: Adam Ford <aford173@xxxxxxxxx>

diff --git a/arch/arm/boot/dts/imx6-logicpd-som.dtsi b/arch/arm/boot/dts/imx6-logicpd-som.dtsi
index 547fb141ec0c..233762acbaaf 100644
--- a/arch/arm/boot/dts/imx6-logicpd-som.dtsi
+++ b/arch/arm/boot/dts/imx6-logicpd-som.dtsi
@@ -15,6 +15,18 @@
reg = <0x10000000 0x80000000>;
};

+ reg_sdhc1: regulator-sdhc1 {
+ compatible = "regulator-fixed";
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_reg_sdhc1>;
+ regulator-name = "reg_sdhc1";
+ regulator-min-microvolt = <3300000>;
+ regulator-max-microvolt = <3300000>;
+ gpio = <&gpio4 5 GPIO_ACTIVE_LOW>;
+ startup-delay-us = <70000>;
+ enable-active-high;
+ };
+
reg_wl18xx_vmmc: regulator-wl18xx {
compatible = "regulator-fixed";
regulator-name = "vwl1837";
@@ -267,6 +279,12 @@
>;
};

+ pinctrl_reg_sdhc1: regsdhc1grp {
+ fsl,pins = <
+ MX6QDL_PAD_GPIO_19__GPIO4_IO05 0x1b0b0
+ >;
+ };
+
pinctrl_tempsense: tempsensegrp {
fsl,pins = <
MX6QDL_PAD_NANDF_CS2__GPIO6_IO15 0x1b0b0
@@ -343,7 +361,9 @@
non-removable;
keep-power-in-suspend;
wakeup-source;
+ no-1-8-v;
vmmc-supply = <&sw2_reg>;
+ vqmmc-supply = <&reg_sdhc1>;
status = "okay";
};

--
2.17.1