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[PATCH] ARM64: dts: meson-gxbb: p20x: add card regulator settle times

Started byJerome Brunet <jbrunet@baylibre.com>
First post2017-08-01 17:30 +0200
Last post2017-08-01 21:50 +0200
Articles 2 — 2 participants

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  [PATCH] ARM64: dts: meson-gxbb: p20x: add card regulator settle times Jerome Brunet <jbrunet@baylibre.com> - 2017-08-01 17:30 +0200
    Re: [PATCH] ARM64: dts: meson-gxbb: p20x: add card regulator settle times Kevin Hilman <khilman@baylibre.com> - 2017-08-01 21:50 +0200

#1701149 — [PATCH] ARM64: dts: meson-gxbb: p20x: add card regulator settle times

FromJerome Brunet <jbrunet@baylibre.com>
Date2017-08-01 17:30 +0200
Subject[PATCH] ARM64: dts: meson-gxbb: p20x: add card regulator settle times
Message-ID<u9Hho-5Gd-23@gated-at.bofh.it>
Changing the card voltage on the p200 is not instantaneous, especially
when switching from 3.3v to 1.8v.

I take at least 70ms for the regulator to go from 3.3v to 1.8v. Add
margin to that to make sure we don't upset the sdcard during the voltage
switch

Fixes: ef8d2ffedf18 ("ARM64: dts: meson-gxbb: add MMC support")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
 arch/arm64/boot/dts/amlogic/meson-gxbb-p20x.dtsi | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb-p20x.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxbb-p20x.dtsi
index 9603a635c7af..d3b194c20b72 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gxbb-p20x.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-gxbb-p20x.dtsi
@@ -84,6 +84,9 @@
 		/* Based on P200 schematics, signal CARD_1.8V/3.3V_CTR */
 		states = <1800000 0
 			  3300000 1>;
+
+		regulator-settling-time-up-us = <10000>;
+		regulator-settling-time-down-us = <150000>;
 	};
 
 	vddio_boot: regulator-vddio_boot {
-- 
2.9.4

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#1701393

FromKevin Hilman <khilman@baylibre.com>
Date2017-08-01 21:50 +0200
Message-ID<u9LkZ-8cw-5@gated-at.bofh.it>
In reply to#1701149
Jerome Brunet <jbrunet@baylibre.com> writes:

> Changing the card voltage on the p200 is not instantaneous, especially
> when switching from 3.3v to 1.8v.
>
> I take at least 70ms for the regulator to go from 3.3v to 1.8v. Add
> margin to that to make sure we don't upset the sdcard during the voltage
> switch
>
> Fixes: ef8d2ffedf18 ("ARM64: dts: meson-gxbb: add MMC support")
> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

Applied to v4.14/dt64,

Thanks,

Kevin

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