Re: [PATCH 2/7] arm64: dts: allwinner: a523: add third usb2 phy

[Krzysztof Kozlowski <krzk@kernel.org>]

On 16/08/2025 10:46, iuncuim wrote:
> From: Mikhail Kalashnikov <iuncuim@gmail.com>
> 
> It seems that there are actually three usb2 phys in the processor, which
> makes it incompatible with D1.
> The third phy is used together with USB3/PCIe combophy with DWC3
> controller. In the BSP code, the third PHY requires a separate glue
> driver, but it seems that it is not needed.
> According to the BSP code, the third phy does not have a reset line; the
> only reset is declared in the DWC3 node, but none of this is documented.
> Since sun4i-usb-phy driver requires a reset, I added RST_BUS_3 here.
> 
> Signed-off-by: Mikhail Kalashnikov <iuncuim@gmail.com>
> ---
>  .../arm64/boot/dts/allwinner/sun55i-a523.dtsi | 21 ++++++++++++-------
>  1 file changed, 13 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/allwinner/sun55i-a523.dtsi b/arch/arm64/boot/dts/allwinner/sun55i-a523.dtsi
> index 6b6f2296b..e4ed4fa82 100644
> --- a/arch/arm64/boot/dts/allwinner/sun55i-a523.dtsi
> +++ b/arch/arm64/boot/dts/allwinner/sun55i-a523.dtsi
> @@ -503,22 +503,27 @@ usb_otg: usb@4100000 {
>  		};
>  
>  		usbphy: phy@4100400 {
> -			compatible = "allwinner,sun55i-a523-usb-phy",
> -				     "allwinner,sun20i-d1-usb-phy";
> +			compatible = "allwinner,sun55i-a523-usb-phy";


That's potential break of all users. Also, having third phy (so
additional piece) is not making things incompatible.



Best regards,
Krzysztof