From 5c03465ecf6a56b7b261df9594f0e10612f53a50 Mon Sep 17 00:00:00 2001 From: Lad Prabhakar Date: Fri, 23 Jan 2026 22:59:57 +0000 Subject: [PATCH] arm64: dts: renesas: rzv2-evk-cn15-sd: Add ramp delay for SD0 regulator Set an appropriate ramp delay for the SD0 I/O voltage regulator in the CN15 SD overlay to make UHS-I voltage switching reliable during card initialization. This issue was observed on the RZ/V2H EVK, while the same UHS-I cards worked on the RZ/V2N EVK without problems. Adding the ramp delay makes the behavior consistent and avoids SD init timeouts. Before this change SD0 could fail with: mmc0: error -110 whilst initialising SD card With the delay in place UHS-I cards enumerate correctly: mmc0: new UHS-I speed SDR104 SDXC card at address aaaa mmcblk0: mmc0:aaaa SR64G 59.5 GiB mmcblk0: p1 Fixes: 3d6c2bc7629c8 ("arm64: dts: renesas: Add CN15 eMMC and SD overlays for RZ/V2H and RZ/V2N EVKs") Signed-off-by: Lad Prabhakar Reviewed-by: Geert Uytterhoeven Link: https://patch.msgid.link/20260123225957.1007089-5-prabhakar.mahadev-lad.rj@bp.renesas.com Signed-off-by: Geert Uytterhoeven --- arch/arm64/boot/dts/renesas/rzv2-evk-cn15-sd.dtso | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/boot/dts/renesas/rzv2-evk-cn15-sd.dtso b/arch/arm64/boot/dts/renesas/rzv2-evk-cn15-sd.dtso index 0af1e0a6c7f4..fc53c1aae3b5 100644 --- a/arch/arm64/boot/dts/renesas/rzv2-evk-cn15-sd.dtso +++ b/arch/arm64/boot/dts/renesas/rzv2-evk-cn15-sd.dtso @@ -25,6 +25,7 @@ regulator-max-microvolt = <3300000>; gpios-states = <0>; states = <3300000 0>, <1800000 1>; + regulator-ramp-delay = <60>; }; };