[PATCH v2 1/2] ARM: dts: imx8m: increase off-on delay on the SD Vcc regulator

[Andrey Zhizhikin]

Some SD Card controller and power circuitry has increased capacitance,
which keeps the internal logic remains powered after regulator is switch
off. This is generally the case when card is switched to SD104 mode,
where a power cycle should be performed. In case if the card internal
logic remains powered, it causes a subsequent failure of mode
transition, effectively leading to failed enumeration.

Introduce a delay of 20 msec in order to provide a possibility for
internal card circuitry to drain voltages and perform a power cycle
correctly.

Similar fix is done in commit c49d0ac38a76 ("ARM: dts: rmobile: Increase
off-on delay on the SD Vcc regulator") targeted Renesas SOCs.

Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin at leica-geosystems.com>
Cc: Stefano Babic <sbabic at denx.de>
---
Changes in v2:
- Moved u-boot binding for imx8mq-evk and imx8mq-phanbell to separate
  autoincluded dtsi files 

 arch/arm/dts/imx8mm-beacon-kit-u-boot.dtsi | 4 ++++
 arch/arm/dts/imx8mm-evk-u-boot.dtsi        | 4 ++++
 arch/arm/dts/imx8mn-ddr4-evk-u-boot.dtsi   | 4 ++++
 arch/arm/dts/imx8mp-evk-u-boot.dtsi        | 4 ++++
 arch/arm/dts/imx8mq-evk-u-boot.dtsi        | 5 +++++
 arch/arm/dts/imx8mq-phanbell-u-boot.dtsi   | 5 +++++
 6 files changed, 26 insertions(+)
 create mode 100644 arch/arm/dts/imx8mq-evk-u-boot.dtsi
 create mode 100644 arch/arm/dts/imx8mq-phanbell-u-boot.dtsi

diff --git a/arch/arm/dts/imx8mm-beacon-kit-u-boot.dtsi b/arch/arm/dts/imx8mm-beacon-kit-u-boot.dtsi
index fc1aebb2fe..6d80a529ae 100644
--- a/arch/arm/dts/imx8mm-beacon-kit-u-boot.dtsi
+++ b/arch/arm/dts/imx8mm-beacon-kit-u-boot.dtsi
@@ -37,6 +37,10 @@
 	/delete-property/ assigned-clock-rates;
 };
 
+&reg_usdhc2_vmmc {
+	u-boot,off-on-delay-us = <20000>;
+};
+
 &fec1 {
 	phy-reset-gpios = <&gpio4 22 GPIO_ACTIVE_LOW>;
 };
diff --git a/arch/arm/dts/imx8mm-evk-u-boot.dtsi b/arch/arm/dts/imx8mm-evk-u-boot.dtsi
index b5c12105a9..9f77d3c6ff 100644
--- a/arch/arm/dts/imx8mm-evk-u-boot.dtsi
+++ b/arch/arm/dts/imx8mm-evk-u-boot.dtsi
@@ -46,6 +46,10 @@
 	u-boot,dm-spl;
 };
 
+&reg_usdhc2_vmmc {
+	u-boot,off-on-delay-us = <20000>;
+};
+
 &pinctrl_reg_usdhc2_vmmc {
 	u-boot,dm-spl;
 };
diff --git a/arch/arm/dts/imx8mn-ddr4-evk-u-boot.dtsi b/arch/arm/dts/imx8mn-ddr4-evk-u-boot.dtsi
index 4419679d4c..98b0b9891b 100644
--- a/arch/arm/dts/imx8mn-ddr4-evk-u-boot.dtsi
+++ b/arch/arm/dts/imx8mn-ddr4-evk-u-boot.dtsi
@@ -47,6 +47,10 @@
 	u-boot,dm-spl;
 };
 
+&reg_usdhc2_vmmc {
+	u-boot,off-on-delay-us = <20000>;
+};
+
 &pinctrl_uart2 {
 	u-boot,dm-spl;
 };
diff --git a/arch/arm/dts/imx8mp-evk-u-boot.dtsi b/arch/arm/dts/imx8mp-evk-u-boot.dtsi
index 24a93ac2d6..2452e9175c 100644
--- a/arch/arm/dts/imx8mp-evk-u-boot.dtsi
+++ b/arch/arm/dts/imx8mp-evk-u-boot.dtsi
@@ -48,6 +48,10 @@
 	u-boot,dm-spl;
 };
 
+&reg_usdhc2_vmmc {
+	u-boot,off-on-delay-us = <20000>;
+};
+
 &reg_usdhc2_vmmc {
 	u-boot,dm-spl;
 };
diff --git a/arch/arm/dts/imx8mq-evk-u-boot.dtsi b/arch/arm/dts/imx8mq-evk-u-boot.dtsi
new file mode 100644
index 0000000000..4712cf6a44
--- /dev/null
+++ b/arch/arm/dts/imx8mq-evk-u-boot.dtsi
@@ -0,0 +1,5 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+
+&reg_usdhc2_vmmc {
+	u-boot,off-on-delay-us = <20000>;
+};
diff --git a/arch/arm/dts/imx8mq-phanbell-u-boot.dtsi b/arch/arm/dts/imx8mq-phanbell-u-boot.dtsi
new file mode 100644
index 0000000000..4712cf6a44
--- /dev/null
+++ b/arch/arm/dts/imx8mq-phanbell-u-boot.dtsi
@@ -0,0 +1,5 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+
+&reg_usdhc2_vmmc {
+	u-boot,off-on-delay-us = <20000>;
+};
-- 
2.17.1