Re: [PATCH] usb: dwc3: qcom: Add support to skip phy management by USB core

Thinh Nguyen <[email protected]> Tue, 4 Aug 2026 23:38:41 +0000
Newsgroups org.kernel.vger.linux-arm-msm,org.kernel.vger.linux-kernel,org.kernel.vger.linux-usb
Message-ID <anJ3JVHWB11b7waE@vbox>
On Thu, Jul 23, 2026, Krishna Kurapati wrote:
> DWC3 driver does manage phys itself sufficiently for Qualcomm platforms.
> If xhci-skip-phy-init is not set, the HCD core does a phy_init and phy_
> exit is done only when roothub is being destroyed. Due to this, during
> system suspend in host mode, although phy_exit is done by DWC3 core, the
> init_count on phy is never down to zero since HCD core also did an init.
> consequently causing phy's exit routine to not be called. Hence, add
> support to skip phy management by USB core.
> 
> Some Exynos platforms still do rely on USB core for phy_calibrate calls,
> hence disable USB core management for Qualcomm platforms only.

So this is a fix applicable to all qcom platforms right? Do we need to
add Fixes tag and backport this change?

Regardless,

Acked-by: Thinh Nguyen <[email protected]>

Thanks,
Thinh

> 
> Signed-off-by: Krishna Kurapati <[email protected]>
> ---
> Link to PHY calibrate handling for Exynos platforms:
> https://urldefense.com/v3/__https://lore.kernel.org/all/[email protected]/__;!!A4F2R9G_pg!aP037GeN4WssfY2NPRwwFsPNYLtng9TCmzBFu8aoGmYWzLzD7vxM-Mt1sOwfv6KUBe7GsvyRbuktzot9dM8jEcYTWSdnmhMkjHJ3rQ$ 
> ---
>  drivers/usb/dwc3/dwc3-qcom.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
> index ac68b4218b56..ba26e61df915 100644
> --- a/drivers/usb/dwc3/dwc3-qcom.c
> +++ b/drivers/usb/dwc3/dwc3-qcom.c
> @@ -19,6 +19,7 @@
>  #include <linux/iopoll.h>
>  #include <linux/usb/hcd.h>
>  #include <linux/usb.h>
> +#include <linux/property.h>
>  #include "core.h"
>  #include "glue.h"
>  
> @@ -419,6 +420,16 @@ static irqreturn_t qcom_dwc3_resume_irq(int irq, void *data)
>  	return IRQ_HANDLED;
>  }
>  
> +static int dwc3_qcom_set_swnode(struct device *dev)
> +{
> +	const struct property_entry props[] = {
> +		PROPERTY_ENTRY_BOOL("xhci-skip-phy-init-quirk"),
> +		{}
> +	};
> +
> +	return device_create_managed_software_node(dev, props, NULL);
> +}
> +
>  static void dwc3_qcom_select_utmi_clk(struct dwc3_qcom *qcom)
>  {
>  	/* Configure dwc3 to use UTMI clock as PIPE clock not present */
> @@ -683,6 +694,10 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
>  	if (ignore_pipe_clk)
>  		dwc3_qcom_select_utmi_clk(qcom);
>  
> +	ret = dwc3_qcom_set_swnode(dev);
> +	if (ret)
> +		goto clk_disable;
> +
>  	qcom->mode = usb_get_dr_mode(dev);
>  
>  	if (qcom->mode == USB_DR_MODE_HOST) {
> 
> ---
> base-commit: 80574c40598aedbc1751c528e414d7e224bc6313
> change-id: 20260720-dwc3-skip-init-quirk-c110eae068ac
> 
> Best regards,
> --  
> Krishna Kurapati <[email protected]>
>