[PATCH] phy: fsl-imx8mq-usb: enable RxTermination_override_sel
Frank Li
Frank.li at nxp.com
Fri Dec 19 07:52:30 PST 2025
On Fri, Dec 19, 2025 at 04:30:04PM +0800, Xu Yang wrote:
> This is to resolve the problem of wakeup system by USB3 device
> insertion if HSIOMIX on, in that case, the USB3 device detects
Do you means USB3 device wrong regconized as USB2?
> RX term on so doesn't downgrade to USB2, so DP/DM wakeup can't
> happen, with this override bit we can force the RX term off when
> enters system suspend, and disable the override after system resume.
Enable RxTermination_override_sel to resolve the problem, which wrong
regongized as USB 2.0 device if USB3 device plug-in when HSIOMIX ON.
No clear why force RX term Off can resolve problem. Please rephrase it.
Frank
>
> Signed-off-by: Li Jun <jun.li at nxp.com>
> Signed-off-by: Xu Yang <xu.yang_2 at nxp.com>
> ---
> drivers/phy/freescale/phy-fsl-imx8mq-usb.c | 15 ++++++++++++++-
> 1 file changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> index 02d9af409b08..0831ed465775 100644
> --- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> @@ -52,6 +52,7 @@
> #define PHY_CTRL5_PCS_TX_SWING_FULL_MASK GENMASK(6, 0)
>
> #define PHY_CTRL6 0x18
> +#define PHY_CTRL6_RXTERM_OVERRIDE_SEL BIT(29)
> #define PHY_CTRL6_ALT_CLK_EN BIT(1)
> #define PHY_CTRL6_ALT_CLK_SEL BIT(0)
>
> @@ -847,6 +848,7 @@ static int imx8mp_usb_phy_init(struct phy *phy)
> static int imx8mq_phy_power_on(struct phy *phy)
> {
> struct imx8mq_usb_phy *imx_phy = phy_get_drvdata(phy);
> + u32 value;
> int ret;
>
> ret = regulator_enable(imx_phy->vbus);
> @@ -863,12 +865,23 @@ static int imx8mq_phy_power_on(struct phy *phy)
> return ret;
> }
>
> - return ret;
> + /* Disable rx term override */
> + value = readl(imx_phy->base + PHY_CTRL6);
> + value &= ~PHY_CTRL6_RXTERM_OVERRIDE_SEL;
> + writel(value, imx_phy->base + PHY_CTRL6);
> +
> + return 0;
> }
>
> static int imx8mq_phy_power_off(struct phy *phy)
> {
> struct imx8mq_usb_phy *imx_phy = phy_get_drvdata(phy);
> + u32 value;
> +
> + /* Override rx term to be 0 */
> + value = readl(imx_phy->base + PHY_CTRL6);
> + value |= PHY_CTRL6_RXTERM_OVERRIDE_SEL;
> + writel(value, imx_phy->base + PHY_CTRL6);
>
> clk_disable_unprepare(imx_phy->alt_clk);
> clk_disable_unprepare(imx_phy->clk);
> --
> 2.34.1
>
More information about the linux-arm-kernel
mailing list