From patchwork Thu Jan  9 14:18:36 2020
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X-Patchwork-Submitter: Michal Simek <michal.simek@xilinx.com>
X-Patchwork-Id: 239318
List-Id: U-Boot discussion <u-boot.lists.denx.de>
From: michal.simek at xilinx.com (Michal Simek)
Date: Thu,  9 Jan 2020 15:18:36 +0100
Subject: [PATCH 4/8] arm64: dts: zcu100-revC: Give wifi some time after
 power-on
In-Reply-To: <cover.1578579516.git.michal.simek@xilinx.com>
References: <cover.1578579516.git.michal.simek@xilinx.com>
Message-ID: <f93290bec7cdb8bae1a7267ffe785b5df6566830.1578579516.git.michal.simek@xilinx.com>

From: Jan Kiszka <jan.kiszka at siemens.com>

Somewhere along recent changes to power control of the wl1831, power-on
became very unreliable on the Ultra96, failing like this:

wl1271_sdio: probe of mmc2:0001:1 failed with error -16
wl1271_sdio: probe of mmc2:0001:2 failed with error -16

After playing with some dt parameters and comparing to other users of
this chip, it turned out we need some power-on delay to make things
stable again. In contrast to those other users which define 200 ms,
Ultra96 is already happy with 10 ms.

Fixes: 5869ba0653b9 ("arm64: zynqmp: Add support for Xilinx zcu100-revC")
Signed-off-by: Jan Kiszka <jan.kiszka at siemens.com>
Acked-by: Ulf Hansson <ulf.hansson at linaro.org>
Signed-off-by: Michal Simek <michal.simek at xilinx.com>
---

 arch/arm/dts/zynqmp-zcu100-revC.dts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/dts/zynqmp-zcu100-revC.dts b/arch/arm/dts/zynqmp-zcu100-revC.dts
index 02573a1f3294..986f50cf323d 100644
--- a/arch/arm/dts/zynqmp-zcu100-revC.dts
+++ b/arch/arm/dts/zynqmp-zcu100-revC.dts
@@ -123,6 +123,7 @@
 	sdio_pwrseq: sdio-pwrseq {
 		compatible = "mmc-pwrseq-simple";
 		reset-gpios = <&gpio 7 GPIO_ACTIVE_LOW>; /* WIFI_EN */
+		post-power-on-delay-ms = <10>;
 	};
 
 	ina226 {