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

From: Frank Li

Date: Wed Jul 15 2026 - 11:52:01 EST


On Wed, Jul 15, 2026 at 07:34:01PM +0800, Xu Yang wrote:
> From: Xu Yang <xu.yang_2@xxxxxxx>
>
> 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@xxxxxxx>
>
> ---
> 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
>
>