ARM: dts: colibri-imx6ull: limit SDIO clock to 25MHz

[ Upstream commit 828db68f4ff1ab6982a36a56522b585160dc8c8e ]

NXP and AzureWave don't recommend using SDIO bus mode 3.3V@50MHz due
to noise affecting the wireless throughput. Colibri iMX6ULL uses only
3.3V signaling for Wi-Fi module AW-CM276NF.

Limit the SDIO Clock on Colibri iMX6ULL to 25MHz.

Fixes: c2e4987e0e02 ("ARM: dts: imx6ull: add Toradex Colibri iMX6ULL support")
Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/arch/arm/boot/dts/imx6ull-colibri-wifi.dtsi b/arch/arm/boot/dts/imx6ull-colibri-wifi.dtsi
index 038d8c90f6dfeafd52cba37b3d5c076bbc67320e..621396884c318dab176c69410b80ec1d9222cd17 100644 (file)
--- a/arch/arm/boot/dts/imx6ull-colibri-wifi.dtsi
+++ b/arch/arm/boot/dts/imx6ull-colibri-wifi.dtsi
@@ -43,6 +43,7 @@
        assigned-clock-rates = <0>, <198000000>;
        cap-power-off-card;
        keep-power-in-suspend;
+       max-frequency = <25000000>;
        mmc-pwrseq = <&wifi_pwrseq>;
        no-1-8-v;
        non-removable;