arm64: dts: imx8m[m,q]-evk: change to use off-on-delay-us in regulator

Some SD Card controller and power circuitry has increased capacitance,
so the usual toggling of regulator to power the card off and on
is insufficient.

According to SD spec, for sd card power reset operation, the sd card
supply voltage needs to be lower than 0.5v and keep over 1ms, otherwise,
next time power back the sd card supply voltage to 3.3v, sd card can't
support SD3.0 mode again.

This patch add the off-on-delay-us, make sure the sd power reset behavior
is align with the specification. Without this patch, when do quick system
suspend/resume test, some sd card can't work at SD3.0 mode after system
resume back.

Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

diff --git a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
index 6800d923aa7e6725bbe4d8250e14a9b04982ce85..3f2b0ad51e18cff7d99e66b0a17e64b1089ab115 100644 (file)
--- a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
@@ -56,6 +56,7 @@
                regulator-min-microvolt = <3300000>;
                regulator-max-microvolt = <3300000>;
                gpio = <&gpio2 19 GPIO_ACTIVE_HIGH>;
+               off-on-delay-us = <20000>;
                enable-active-high;
        };
 

diff --git a/arch/arm64/boot/dts/freescale/imx8mq-evk.dts b/arch/arm64/boot/dts/freescale/imx8mq-evk.dts
index 2102e9b57697c1664a2aded281c6076c0ec13634..78937910f40398fe09bc7d45029df0ba012c074c 100644 (file)
--- a/arch/arm64/boot/dts/freescale/imx8mq-evk.dts
+++ b/arch/arm64/boot/dts/freescale/imx8mq-evk.dts
@@ -46,6 +46,7 @@
                regulator-min-microvolt = <3300000>;
                regulator-max-microvolt = <3300000>;
                gpio = <&gpio2 19 GPIO_ACTIVE_HIGH>;
+               off-on-delay-us = <20000>;
                enable-active-high;
        };