Messages in this thread Patch in this message | | | From | "Peng Fan (OSS)" <> | Subject | [PATCH V5 11/12] arm64: dts: imx8m[m,q]-evk: change to use off-on-delay-us in regulator | Date | Tue, 15 Nov 2022 17:17:08 +0800 |
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From: Haibo Chen <haibo.chen@nxp.com>
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> --- arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi | 1 + arch/arm64/boot/dts/freescale/imx8mq-evk.dts | 1 + 2 files changed, 2 insertions(+)
diff --git a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi index 7d6317d95b13..f881494996a1 100644 --- a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi +++ b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi @@ -56,6 +56,7 @@ reg_usdhc2_vmmc: regulator-usdhc2 { 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 82387b9cb800..07d9fb2aacf8 100644 --- a/arch/arm64/boot/dts/freescale/imx8mq-evk.dts +++ b/arch/arm64/boot/dts/freescale/imx8mq-evk.dts @@ -46,6 +46,7 @@ reg_usdhc2_vmmc: regulator-vsd-3v3 { regulator-min-microvolt = <3300000>; regulator-max-microvolt = <3300000>; gpio = <&gpio2 19 GPIO_ACTIVE_HIGH>; + off-on-delay-us = <20000>; enable-active-high; }; -- 2.37.1
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