linux-kernel - Re: [PATCH 1/2] phy: qcom: phy-qcom-snps-eusb2: Make repeater optional

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Message-ID: <6yykvszzbhonc3dkwhva55arsdvp4hv4p2fo2vv6ftwr46httm@wnofgs4jaqaa>
Date: Wed, 19 Mar 2025 12:20:07 +0200
From: Dmitry Baryshkov <dmitry.baryshkov@....qualcomm.com>
To: bjorn.andersson@....qualcomm.com
Cc: Vinod Koul <vkoul@...nel.org>, Kishon Vijay Abraham I <kishon@...nel.org>,
        Bjorn Andersson <andersson@...nel.org>,
        Konrad Dybcio <konradybcio@...nel.org>, Rob Herring <robh@...nel.org>,
        Krzysztof Kozlowski <krzk+dt@...nel.org>,
        Conor Dooley <conor+dt@...nel.org>,
        Aleksandrs Vinarskis <alex.vinarskis@...il.com>,
        linux-arm-msm@...r.kernel.org, linux-phy@...ts.infradead.org,
        linux-kernel@...r.kernel.org, devicetree@...r.kernel.org
Subject: Re: [PATCH 1/2] phy: qcom: phy-qcom-snps-eusb2: Make repeater
 optional

On Tue, Mar 18, 2025 at 10:22:56PM -0500, Bjorn Andersson via B4 Relay wrote:
> From: Bjorn Andersson <bjorn.andersson@....qualcomm.com>
> 
> In a multiport configuration based on the SNPS eUSB2 PHY it's not
> necessary that all ports are connected to something.
> 
> While this is allowed by the Devicetree binding, the implementation
> current fails probing for such PHYs, which also prevents the multiport
> controller from probing.
> 
> The lack of repeater does not alter the fact that the PHY is there and
> attempts at describing only the used PHYs in Devicetree results in
> failures to initialize the USB controller.
> 
> Make the repeater optional, to allow the these PHYs to be described in
> the DeviceTree and for the associated multiport controller to operate
> the other ports.
> 
> Signed-off-by: Bjorn Andersson <bjorn.andersson@....qualcomm.com>
> ---
>  drivers/phy/qualcomm/phy-qcom-snps-eusb2.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/phy/qualcomm/phy-qcom-snps-eusb2.c b/drivers/phy/qualcomm/phy-qcom-snps-eusb2.c
> index 1484691a41d59a7eaf257ef44300827c668bf7e0..8897d2072ccfcaa5b4a510c17761dcdeed5bad0f 100644
> --- a/drivers/phy/qualcomm/phy-qcom-snps-eusb2.c
> +++ b/drivers/phy/qualcomm/phy-qcom-snps-eusb2.c
> @@ -401,9 +401,13 @@ static int qcom_snps_eusb2_hsphy_probe(struct platform_device *pdev)
>  				     "failed to get regulator supplies\n");
>  
>  	phy->repeater = devm_of_phy_get_by_index(dev, np, 0);
> -	if (IS_ERR(phy->repeater))
> -		return dev_err_probe(dev, PTR_ERR(phy->repeater),
> -				     "failed to get repeater\n");
> +	if (IS_ERR(phy->repeater)) {
> +		if (PTR_ERR(phy->repeater) == -ENODEV)
> +			phy->repeater = NULL;
> +		else
> +			return dev_err_probe(dev, PTR_ERR(phy->repeater),
> +					     "failed to get repeater\n");

Can you use devm_of_phy_optional_get() or devm_phy_optional_get()
instead?

> +	}
>  
>  	generic_phy = devm_phy_create(dev, NULL, &qcom_snps_eusb2_hsphy_ops);
>  	if (IS_ERR(generic_phy)) {
> 
> -- 
> 2.48.1
> 
> 
> 
> -- 
> linux-phy mailing list
> linux-phy@...ts.infradead.org
> https://lists.infradead.org/mailman/listinfo/linux-phy

-- 
With best wishes
Dmitry

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