4.20-stable review patch. If anyone has any objections, please let me know.
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From: Jan Kiszka jan.kiszka@siemens.com
commit 35a4f89cd4731ac6ec985cd29ddc1630903006b7 upstream.
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@siemens.com Acked-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Michal Simek michal.simek@xilinx.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/arm64/boot/dts/xilinx/zynqmp-zcu100-revC.dts | 1 + 1 file changed, 1 insertion(+)
--- 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>; }; };