arm64: dts: hikey: Give wifi some time after power-on
authorJan Kiszka <jan.kiszka@siemens.com>
Thu, 24 Jan 2019 07:52:33 +0000 (08:52 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 13 Mar 2019 21:02:39 +0000 (14:02 -0700)
commite6eb5e3561ca8bcee04cfbe7de9acaa31159638e
tree351096aeb56a3efd062ab9839410aad88e464200
parent271c5a5d546ba6daecf101d6cf89ea162f2a1e1d
arm64: dts: hikey: Give wifi some time after power-on

commit 83b944174ad79825ae84a47af1a0354485b24602 upstream.

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 would already be happy with 1 ms. Still, we use the safer 10 ms,
like on the Ultra96.

Fixes: ea452678734e ("arm64: dts: hikey: Fix WiFi support")
Cc: <stable@vger.kernel.org> #4.12+
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts