4.20-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jan Kiszka jan.kiszka@siemens.com
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 | 1 + 1 file changed, 1 insertion(+)
--- 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 = <10>; power-off-delay-us = <10>; };