Re: [PATCH] arm64: dts: hikey: Give wifi some time after power-on

From: John Stultz
Date: Wed Jan 02 2019 - 17:21:17 EST


Adding a few folks to cc from the thread here:
https://patchwork.kernel.org/patch/10734021/

As this sounds like a very similar issue.
thanks
-john

On Sun, Dec 30, 2018 at 3:38 AM Jan Kiszka <jan.kiszka@xxxxxx> wrote:
>
> 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, the
> hikey is already very happy with 1 ms.
>
> Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
> ---
>
> Tested with 4.19 and linus/master.
>
> arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
> b/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
> index f4964bee6a1a..1e771bf201b9 100644
> --- a/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
> +++ b/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
> @@ -118,6 +118,7 @@
> reset-gpios = <&gpio0 5 GPIO_ACTIVE_LOW>;
> clocks = <&pmic>;
> clock-names = "ext_clock";
> + post-power-on-delay-ms = <1>;
> power-off-delay-us = <10>;
> };
>
> --
> 2.16.4