[PATCH] arm64: dts: zcu100-revC: Give wifi some time after power-on

From: Jan Kiszka
Date: Thu Jan 24 2019 - 02:54:45 EST


From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>

Somewhere along recent changes to power control of the wl1835, power-on
became very unreliable on the hikey, 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: ea452678734e ("arm64: dts: hikey: Fix WiFi support")
Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
Acked-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
---
arch/arm64/boot/dts/xilinx/zynqmp-zcu100-revC.dts | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/xilinx/zynqmp-zcu100-revC.dts b/arch/arm64/boot/dts/xilinx/zynqmp-zcu100-revC.dts
index 13a0a028df98..e5699d0d91e4 100644
--- a/arch/arm64/boot/dts/xilinx/zynqmp-zcu100-revC.dts
+++ b/arch/arm64/boot/dts/xilinx/zynqmp-zcu100-revC.dts
@@ -101,6 +101,7 @@
sdio_pwrseq: sdio-pwrseq {
compatible = "mmc-pwrseq-simple";
reset-gpios = <&gpio 7 GPIO_ACTIVE_LOW>; /* WIFI_EN */
+ post-power-on-delay-ms = <10>;
};
};

--
2.16.4