Re: [PATCH v6 6/6] phy: fsl-imx8mq-usb: keep PHY power domain runtime always-on for i.MX8MP

From: Frank Li <Frank.li@oss.nxp.com>
To: Xu Yang <xu.yang_2@oss.nxp.com>
Cc: Vinod Koul <vkoul@kernel.org>,
	Neil Armstrong <neil.armstrong@linaro.org>,
	Frank Li <Frank.Li@nxp.com>,
	Sascha Hauer <s.hauer@pengutronix.de>,
	Pengutronix Kernel Team <kernel@pengutronix.de>,
	Fabio Estevam <festevam@gmail.com>, Jun Li <jun.li@nxp.com>,
	linux-phy@lists.infradead.org, imx@lists.linux.dev,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, Xu Yang <xu.yang_2@nxp.com>
Subject: Re: [PATCH v6 6/6] phy: fsl-imx8mq-usb: keep PHY power domain runtime always-on for i.MX8MP
Date: Wed, 15 Jul 2026 10:32:40 -0500	[thread overview]
Message-ID: <aleoGO5hBWCl6ZgE@SMW015318> (raw)
In-Reply-To: <20260715-imx8mp-usb-phy-improvement-v6-6-00d95e270e4c@nxp.com>

On Wed, Jul 15, 2026 at 07:34:01PM +0800, Xu Yang wrote:
> From: Xu Yang <xu.yang_2@nxp.com>
>
> On i.MX8MP, the USB PHY has a dedicated power domain that was previously
> never powered off at runtime. With the introduction of runtime PM support,
> the power domain will be powered off if the device is runtime suspended,
> which breaks USB wakeup functionality.
>
> To preserve wakeup functionality, mark the PHY power domain as runtime
> always-on for i.MX8MP platform. To limit the behavior to i.MX8MP, add a
> need_genpd_rpm_on to imx8mq_usb_phy_drvdata and set it as true for i.MX8MP.
>
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
>
> ---
> Changes in v6:
>  - set need_genpd_rpm_on flag for i.MX8MP and call dev_pm_genpd_rpm_always_on()
>    if the flag is true
> Changes in v5:
>  - no changes
> Changes in v4:
>  - no changes
> Changes in v3:
>  - new patch
> ---
>  drivers/phy/freescale/phy-fsl-imx8mq-usb.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
>
> diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> index f0bdfa75d586..2398bda50eb8 100644
> --- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> @@ -9,6 +9,7 @@
>  #include <linux/of.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
> +#include <linux/pm_domain.h>
>  #include <linux/pm_runtime.h>
>  #include <linux/regulator/consumer.h>
>  #include <linux/regmap.h>
> @@ -134,6 +135,7 @@ struct imx8mq_usb_phy {
>
>  struct imx8mq_usb_phy_drvdata {
>  	const struct phy_ops *ops;
> +	bool need_genpd_rpm_on;
>  };
>
>  static void tca_blk_orientation_set(struct tca_blk *tca,
> @@ -669,6 +671,7 @@ static const struct imx8mq_usb_phy_drvdata imx8mq_usb_phy_data = {
>
>  static const struct imx8mq_usb_phy_drvdata imx8mp_usb_phy_data = {
>  	.ops = &imx8mp_usb_phy_ops,
> +	.need_genpd_rpm_on = true,
>  };
>
>  static const struct imx8mq_usb_phy_drvdata imx95_usb_phy_data = {
> @@ -739,6 +742,12 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
>  	if (!phy_data)
>  		return -EINVAL;
>
> +	if (phy_data->need_genpd_rpm_on) {
> +		ret = dev_pm_genpd_rpm_always_on(dev, true);
> +		if (ret)
> +			return dev_err_probe(dev, ret, "failed to set genpd rpm always on\n");
> +	}
> +

need set false at driver remove?

Frank

>  	imx_phy->phy = devm_phy_create(dev, NULL, phy_data->ops);
>  	if (IS_ERR(imx_phy->phy))
>  		return PTR_ERR(imx_phy->phy);
>
> --
> 2.34.1
>
>

-- 
linux-phy mailing list
linux-phy@lists.infradead.org
https://lists.infradead.org/mailman/listinfo/linux-phy