Re: [PATCH] arm64: dts: imx8mp-phyboard-pollux: add PEB-WLBT-07 expansion board

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Missing `post-power-on-delay-ms` in the MMC power sequence for the NXP IW612 Wi-Fi/BT module.
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commit 60b0b6fcfb75ad1ee4054d84dfea3d70e8467993
Author: Primoz Fiser <primoz.fiser@norik.com>

arm64: dts: imx8mp-phyboard-pollux: add PEB-WLBT-07 expansion board

Add support for PEB-WLBT-07 which is an expansion board that provides WiFi 6
and Bluetooth 5.4 LE functionality. It features the u-blox MAYA-W2 module
with the NXP IW612 chipset.

[ ... ]

> diff --git a/arch/arm64/boot/dts/freescale/imx8mp-phyboard-pollux-peb-wlbt-07.dtso b/arch/arm64/boot/dts/freescale/imx8mp-phyboard-pollux-peb-wlbt-07.dtso
> new file mode 100644
> index 0000000000000..008b6f9f46e59
> --- /dev/null
> +++ b/arch/arm64/boot/dts/freescale/imx8mp-phyboard-pollux-peb-wlbt-07.dtso
> @@ -0,0 +1,76 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
> +/*
> +* Copyright (C) 2026 PHYTEC Messtechnik GmbH
> +*/
> +
> +#include <dt-bindings/clock/imx8mp-clock.h>
> +#include <dt-bindings/gpio/gpio.h>
> +#include <dt-bindings/interrupt-controller/irq.h>
> +#include "imx8mp-pinfunc.h"
> +
> +/dts-v1/;
> +/plugin/;
> +
> +&{/} {
> +	usdhc1_pwrseq: pwr-seq {
> +		compatible = "mmc-pwrseq-simple";
> +		reset-gpios = <&gpio2 7 GPIO_ACTIVE_LOW>;
> +	};

[Severity: Medium]
Is it possible that the usdhc1_pwrseq node needs a post-power-on-delay-ms
property here?

When the MMC core powers up the SDIO bus, it deasserts the reset GPIO and
immediately proceeds to probe the module with no explicit delay. If the
SDIO host controller probes the IW612 module immediately after the reset
deassertion and the hardware is not yet stabilized, could this cause SDIO
enumeration failures during device boot or resume?

Other in-tree configurations for the IW61x chipset, such as those in
imx8mm-var-som-wifi-bt-iw61x.dtsi, explicitly configure a delay like
post-power-on-delay-ms = <100>. While there might be an on-board hardware
RC delay on the MAYA-W2 module that mitigates the missing software delay,
adding the explicit software delay might be necessary to guarantee stability.

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260827075754.2739119-1-primoz.fiser@norik.com?part=1