Re: [RFC v3 5/7] phy: qcom: phy-qcom-snps-eusb2: Add support for eUSB2 repeater

From: Vinod Koul <vkoul@kernel.org>
To: Abel Vesa <abel.vesa@linaro.org>
Cc: Andy Gross <agross@kernel.org>,
	Bjorn Andersson <andersson@kernel.org>,
	Konrad Dybcio <konrad.dybcio@linaro.org>,
	Lee Jones <lee@kernel.org>, Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Kishon Vijay Abraham I <kishon@kernel.org>,
	linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-phy@lists.infradead.org,
	Neil Armstrong <neil.armstrong@linaro.org>
Subject: Re: [RFC v3 5/7] phy: qcom: phy-qcom-snps-eusb2: Add support for eUSB2 repeater
Date: Fri, 3 Feb 2023 19:19:22 +0530	[thread overview]
Message-ID: <Y90Q4rDYw9kcXmCQ@matsya> (raw)
In-Reply-To: <20230202133816.4026990-6-abel.vesa@linaro.org>

On 02-02-23, 15:38, Abel Vesa wrote:
> From: Neil Armstrong <neil.armstrong@linaro.org>
> 
> For USB 2.0 compliance, eUSB2 needs a repeater. The PHY needs to
> initialize and reset it. So add repeater support
> 
> Co-developed-by: Abel Vesa <abel.vesa@linaro.org>
> Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
> ---
>  drivers/phy/qualcomm/phy-qcom-snps-eusb2.c | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/phy/qualcomm/phy-qcom-snps-eusb2.c b/drivers/phy/qualcomm/phy-qcom-snps-eusb2.c
> index 23ec162cc3bd..8d972d49732b 100644
> --- a/drivers/phy/qualcomm/phy-qcom-snps-eusb2.c
> +++ b/drivers/phy/qualcomm/phy-qcom-snps-eusb2.c
> @@ -128,6 +128,8 @@ struct qcom_snps_eusb2_hsphy {
>  	struct regulator_bulk_data vregs[EUSB2_NUM_VREGS];
>  
>  	enum phy_mode mode;
> +
> +	struct phy *repeater;
>  };
>  
>  static int qcom_snps_eusb2_hsphy_set_mode(struct phy *p, enum phy_mode mode, int submode)
> @@ -136,7 +138,7 @@ static int qcom_snps_eusb2_hsphy_set_mode(struct phy *p, enum phy_mode mode, int
>  
>  	phy->mode = mode;
>  
> -	return 0;
> +	return phy_set_mode_ext(phy->repeater, mode, submode);
>  }
>  
>  static void qcom_snps_eusb2_hsphy_write_mask(void __iomem *base, u32 offset,
> @@ -235,6 +237,12 @@ static int qcom_snps_eusb2_hsphy_init(struct phy *p)
>  	if (ret)
>  		return ret;
>  
> +	ret = phy_init(phy->repeater);
> +	if (ret) {
> +		dev_err(&p->dev, "repeater init failed. %d\n", ret);
> +		goto disable_vreg;
> +	}
> +
>  	ret = clk_prepare_enable(phy->ref_clk);
>  	if (ret) {
>  		dev_err(&p->dev, "failed to enable ref clock, %d\n", ret);
> @@ -342,6 +350,8 @@ static int qcom_snps_eusb2_hsphy_exit(struct phy *p)
>  
>  	regulator_bulk_disable(ARRAY_SIZE(phy->vregs), phy->vregs);
>  
> +	phy_exit(phy->repeater);
> +
>  	return 0;
>  }
>  
> @@ -386,6 +396,12 @@ static int qcom_snps_eusb2_hsphy_probe(struct platform_device *pdev)
>  	if (ret)
>  		return dev_err_probe(dev, ret,
>  				     "failed to get regulator supplies\n");
> +
> +	phy->repeater = devm_phy_get(dev, "eusb2-repeater");
> +	if (IS_ERR(phy->repeater))
> +		return dev_err_probe(dev, PTR_ERR(phy->repeater),
> +				     "failed to get repeater\n");

That implies repeater is assumed to be there for all designs, how about
older devices, they may not have a repeater?

> +
>  	generic_phy = devm_phy_create(dev, NULL, &qcom_snps_eusb2_hsphy_ops);
>  	if (IS_ERR(generic_phy)) {
>  		dev_err(dev, "failed to create phy %d\n", ret);
> -- 
> 2.34.1

-- 
~Vinod