[PATCH v2 15/19] imx: kontron-sl-mx8mm: Use the VSELECT signal to switch SD card IO voltage

Frieder Schrempf frieder at fris.de
Mon Aug 1 12:30:17 CEST 2022


From: Frieder Schrempf <frieder.schrempf at kontron.de>

It turns out that it is not necessary to declare the VSELECT signal as
GPIO and let the PMIC driver set it to a fixed high level. This switches
the voltage between 3.3V and 1.8V by setting the PMIC register for LDO5
accordingly.

Instead we can do it like other boards already do and simply mux the
VSELECT signal of the USDHC interface to the pin. This makes sure that
the correct voltage is selected by setting the PMIC's SD_VSEL input
to high or low accordingly.

Reported-by: Heiko Thiery <heiko.thiery at gmail.com>
Signed-off-by: Frieder Schrempf <frieder.schrempf at kontron.de>
Reviewed-by: Heiko Thiery <heiko.thiery at gmail.com>
---
Changes in v2:
* add Heiko's R-b tag (thanks!)
---
 arch/arm/dts/imx8mm-kontron-n801x-s-u-boot.dtsi | 5 -----
 arch/arm/dts/imx8mm-kontron-n801x-s.dts         | 3 +++
 arch/arm/dts/imx8mm-kontron-n801x-som.dtsi      | 2 --
 3 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/arch/arm/dts/imx8mm-kontron-n801x-s-u-boot.dtsi b/arch/arm/dts/imx8mm-kontron-n801x-s-u-boot.dtsi
index 2c62f05cec1..a42881d1a89 100644
--- a/arch/arm/dts/imx8mm-kontron-n801x-s-u-boot.dtsi
+++ b/arch/arm/dts/imx8mm-kontron-n801x-s-u-boot.dtsi
@@ -62,11 +62,6 @@
 
 &pinctrl_pmic {
 	u-boot,dm-spl;
-	fsl,pins = <
-		MX8MM_IOMUXC_GPIO1_IO00_GPIO1_IO0		0x141
-		/* Disable Pullup for SD_VSEL */
-		MX8MM_IOMUXC_GPIO1_IO04_GPIO1_IO4		0x41
-	>;
 };
 
 &pinctrl_uart3 {
diff --git a/arch/arm/dts/imx8mm-kontron-n801x-s.dts b/arch/arm/dts/imx8mm-kontron-n801x-s.dts
index cb8102bb8db..bc46426ad8f 100644
--- a/arch/arm/dts/imx8mm-kontron-n801x-s.dts
+++ b/arch/arm/dts/imx8mm-kontron-n801x-s.dts
@@ -321,6 +321,7 @@
 			MX8MM_IOMUXC_SD2_DATA2_USDHC2_DATA2		0x1d0
 			MX8MM_IOMUXC_SD2_DATA3_USDHC2_DATA3		0x1d0
 			MX8MM_IOMUXC_SD2_CD_B_GPIO2_IO12		0x019
+			MX8MM_IOMUXC_GPIO1_IO04_USDHC2_VSELECT		0x1d0
 		>;
 	};
 
@@ -333,6 +334,7 @@
 			MX8MM_IOMUXC_SD2_DATA2_USDHC2_DATA2		0x1d4
 			MX8MM_IOMUXC_SD2_DATA3_USDHC2_DATA3		0x1d4
 			MX8MM_IOMUXC_SD2_CD_B_GPIO2_IO12		0x019
+			MX8MM_IOMUXC_GPIO1_IO04_USDHC2_VSELECT		0x1d0
 		>;
 	};
 
@@ -345,6 +347,7 @@
 			MX8MM_IOMUXC_SD2_DATA2_USDHC2_DATA2		0x1d6
 			MX8MM_IOMUXC_SD2_DATA3_USDHC2_DATA3		0x1d6
 			MX8MM_IOMUXC_SD2_CD_B_GPIO2_IO12		0x019
+			MX8MM_IOMUXC_GPIO1_IO04_USDHC2_VSELECT		0x1d0
 		>;
 	};
 };
diff --git a/arch/arm/dts/imx8mm-kontron-n801x-som.dtsi b/arch/arm/dts/imx8mm-kontron-n801x-som.dtsi
index 1cd752b2973..cd689fa8212 100644
--- a/arch/arm/dts/imx8mm-kontron-n801x-som.dtsi
+++ b/arch/arm/dts/imx8mm-kontron-n801x-som.dtsi
@@ -103,7 +103,6 @@
 		pinctrl-0 = <&pinctrl_pmic>;
 		interrupt-parent = <&gpio1>;
 		interrupts = <0 IRQ_TYPE_LEVEL_LOW>;
-		sd-vsel-gpios = <&gpio1 4 GPIO_ACTIVE_HIGH>;
 
 		regulators {
 			reg_vdd_soc: BUCK1 {
@@ -246,7 +245,6 @@
 	pinctrl_pmic: pmicgrp {
 		fsl,pins = <
 			MX8MM_IOMUXC_GPIO1_IO00_GPIO1_IO0		0x141
-			MX8MM_IOMUXC_GPIO1_IO04_GPIO1_IO4		0x141
 		>;
 	};
 
-- 
2.37.1



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