diff mbox series

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

Message ID 20210713195416.277153-1-oleksandr.suvorov@toradex.com (mailing list archive)
State New, archived
Headers show
Series ARM: dts: colibri-imx6ull: limit SDIO clock to 25MHz | expand

Commit Message

Oleksandr Suvorov July 13, 2021, 7:54 p.m. UTC 
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.

Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
---

 arch/arm/boot/dts/imx6ull-colibri-wifi.dtsi | 1 +
 1 file changed, 1 insertion(+)

Comments

Fabio Estevam July 13, 2021, 8:09 p.m. UTC | #1 
Hi Oleksandr,

On Tue, Jul 13, 2021 at 4:54 PM Oleksandr Suvorov
<oleksandr.suvorov@toradex.com> wrote:
>
> 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.

What about adding a Fixes tag so that it can go to the stable trees?

Reviewed-by: Fabio Estevam <festevam@gmail.com>
Oleksandr Suvorov July 13, 2021, 8:23 p.m. UTC | #2 
Hi Fabio,
On Tue, Jul 13, 2021 at 11:10 PM Fabio Estevam <festevam@gmail.com> wrote:
>
> Hi Oleksandr,
>
> On Tue, Jul 13, 2021 at 4:54 PM Oleksandr Suvorov
> <oleksandr.suvorov@toradex.com> wrote:
> >
> > 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.
>
> What about adding a Fixes tag so that it can go to the stable trees?

Good point, thanks! I'll add in the 2nd version.
>
> Reviewed-by: Fabio Estevam <festevam@gmail.com>

Thanks for the review!

Best regards
Oleksandr Suvorov

Toradex AG
Ebenaustrasse 10 | 6048 Horw | Switzerland | T: +41 41 500 48 00
diff mbox series

Patch

diff --git a/arch/arm/boot/dts/imx6ull-colibri-wifi.dtsi b/arch/arm/boot/dts/imx6ull-colibri-wifi.dtsi
index a0545431b3dc..9f1e38282bee 100644
--- a/arch/arm/boot/dts/imx6ull-colibri-wifi.dtsi
+++ b/arch/arm/boot/dts/imx6ull-colibri-wifi.dtsi
@@ -43,6 +43,7 @@  &usdhc2 {
 	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;