* [PATCH 1/2] usb: host: xhci: Allow non-Intel usb_link_tunnel_mode reporting
2026-05-05 8:55 [PATCH 0/2] DWC3 link tunneling state reporting Konrad Dybcio
@ 2026-05-05 8:55 ` Konrad Dybcio
2026-05-05 12:14 ` Mika Westerberg
2026-05-05 8:55 ` [PATCH 2/2] usb: dwc3: Notify XHCI core of tunneled status Konrad Dybcio
1 sibling, 1 reply; 4+ messages in thread
From: Konrad Dybcio @ 2026-05-05 8:55 UTC (permalink / raw)
To: Thinh Nguyen, Greg Kroah-Hartman, Mathias Nyman
Cc: linux-usb, linux-kernel, usb4-upstream, Raghavendra Thoorpu,
Mika Westerberg, Konrad Dybcio
From: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
The Thunderbolt framework relies on the USB core to create device links
for tunneled ports, so that the USB3 controller is only kept
runtime-resumed for the duration of the tunneling.
Currently, retrieving that information is only possibe on Intel XHCI
hosts, through a vendor-specific capability. Extend xhci-plat to allow
plumbing a custom one.
Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
---
drivers/usb/host/xhci-hub.c | 4 ++--
drivers/usb/host/xhci-plat.c | 2 ++
drivers/usb/host/xhci-plat.h | 1 +
drivers/usb/host/xhci.c | 6 +++++-
drivers/usb/host/xhci.h | 5 ++++-
5 files changed, 14 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index bacd0ddd0d09..09e5da912066 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -750,7 +750,7 @@ static int xhci_exit_test_mode(struct xhci_hcd *xhci)
}
/**
- * xhci_port_is_tunneled() - Check if USB3 connection is tunneled over USB4
+ * xhci_port_tunnel_mode() - Check if USB3 connection is tunneled over USB4
* @xhci: xhci host controller
* @port: USB3 port to be checked.
*
@@ -764,7 +764,7 @@ static int xhci_exit_test_mode(struct xhci_hcd *xhci)
* detecting USB3 over USB4 tunnels. USB_LINK_NATIVE or USB_LINK_TUNNELED
* otherwise.
*/
-enum usb_link_tunnel_mode xhci_port_is_tunneled(struct xhci_hcd *xhci,
+enum usb_link_tunnel_mode xhci_port_tunnel_mode(struct xhci_hcd *xhci,
struct xhci_port *port)
{
struct usb_hcd *hcd;
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 074d9c731639..dbaca694baa2 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -244,6 +244,8 @@ int xhci_plat_probe(struct platform_device *pdev, struct device *sysdev, const s
priv = hcd_to_xhci_priv(hcd);
/* Just copy data for now */
*priv = *priv_match;
+
+ xhci->tunnel_mode = priv->tunnel_mode;
}
device_set_wakeup_capable(&pdev->dev, true);
diff --git a/drivers/usb/host/xhci-plat.h b/drivers/usb/host/xhci-plat.h
index 00751d851831..c5042766a486 100644
--- a/drivers/usb/host/xhci-plat.h
+++ b/drivers/usb/host/xhci-plat.h
@@ -22,6 +22,7 @@ struct xhci_plat_priv {
int (*suspend_quirk)(struct usb_hcd *);
int (*resume_quirk)(struct usb_hcd *);
int (*post_resume_quirk)(struct usb_hcd *);
+ enum usb_link_tunnel_mode (*tunnel_mode)(struct usb_hcd *hcd, int portnum);
};
#define hcd_to_xhci_priv(h) ((struct xhci_plat_priv *)hcd_to_xhci(h)->priv)
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index a54f5b57f205..90a6751b5c69 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -4754,7 +4754,11 @@ static int xhci_update_device(struct usb_hcd *hcd, struct usb_device *udev)
if (hcd->speed >= HCD_USB3 && !udev->parent->parent) {
port = xhci->usb3_rhub.ports[udev->portnum - 1];
- udev->tunnel_mode = xhci_port_is_tunneled(xhci, port);
+ if (xhci->tunnel_mode)
+ udev->tunnel_mode = xhci->tunnel_mode(hcd, port->hcd_portnum);
+ else
+ udev->tunnel_mode = xhci_port_tunnel_mode(xhci, port);
+
if (udev->tunnel_mode == USB_LINK_UNKNOWN)
dev_dbg(&udev->dev, "link tunnel state unknown\n");
else if (udev->tunnel_mode == USB_LINK_TUNNELED)
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index aeecd301f207..59cc5797d5d2 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1672,6 +1672,9 @@ struct xhci_hcd {
struct list_head regset_list;
void *dbc;
+
+ enum usb_link_tunnel_mode (*tunnel_mode)(struct usb_hcd *hcd, int portnum);
+
/* platform-specific data -- must come last */
unsigned long priv[] __aligned(sizeof(s64));
};
@@ -1977,7 +1980,7 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, u16 wIndex,
int xhci_hub_status_data(struct usb_hcd *hcd, char *buf);
int xhci_find_raw_port_number(struct usb_hcd *hcd, int port1);
struct xhci_hub *xhci_get_rhub(struct usb_hcd *hcd);
-enum usb_link_tunnel_mode xhci_port_is_tunneled(struct xhci_hcd *xhci,
+enum usb_link_tunnel_mode xhci_port_tunnel_mode(struct xhci_hcd *xhci,
struct xhci_port *port);
void xhci_hc_died(struct xhci_hcd *xhci);
--
2.54.0
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH 2/2] usb: dwc3: Notify XHCI core of tunneled status
2026-05-05 8:55 [PATCH 0/2] DWC3 link tunneling state reporting Konrad Dybcio
2026-05-05 8:55 ` [PATCH 1/2] usb: host: xhci: Allow non-Intel usb_link_tunnel_mode reporting Konrad Dybcio
@ 2026-05-05 8:55 ` Konrad Dybcio
1 sibling, 0 replies; 4+ messages in thread
From: Konrad Dybcio @ 2026-05-05 8:55 UTC (permalink / raw)
To: Thinh Nguyen, Greg Kroah-Hartman, Mathias Nyman
Cc: linux-usb, linux-kernel, usb4-upstream, Raghavendra Thoorpu,
Mika Westerberg, Konrad Dybcio
From: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
The Thunderbolt framework relies on the USB core to create device links
for tunneled ports, so that the USB3 controller is only kept
runtime-resumed for the duration of the tunneling. This depends on
first knowing whether a connection is tunneled or native.
Add the logic to handle that for DWC3 controllers.
Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
---
drivers/usb/dwc3/core.c | 12 ++++++++++++
drivers/usb/dwc3/core.h | 18 ++++++++++++++++++
drivers/usb/dwc3/host.c | 12 ++++++++++++
3 files changed, 42 insertions(+)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 65213896de99..7cec4911e278 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -162,6 +162,18 @@ void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode, bool ignore_susphy)
}
EXPORT_SYMBOL_GPL(dwc3_set_prtcap);
+enum usb_link_tunnel_mode dwc3_link_tunnel_mode(struct dwc3 *dwc, u8 port)
+{
+ /* Prior versions had no CIO support */
+ if (!DWC3_VER_IS_WITHIN(DWC31, 191A, ANY))
+ return USB_LINK_NATIVE;
+
+ if (dwc3_readl(dwc, DWC3_CIOCTRL(port)) & DWC3_CIOCTRL_CIO_EN)
+ return USB_LINK_TUNNELED;
+
+ return USB_LINK_NATIVE;
+}
+
static void __dwc3_set_mode(struct work_struct *work)
{
struct dwc3 *dwc = work_to_dwc(work);
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index e0dee9d28740..9594829de6c7 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -179,6 +179,11 @@
#define DWC3_OEVTEN 0xcc0C
#define DWC3_OSTS 0xcc10
+/* CIO regs */
+#define DWC3_CIO_BASE(n) (0xcd20 + ((n) * 0x30))
+#define DWC3_CIOCTRL(n) (DWC3_CIO_BASE(n) + 0x00)
+#define DWC3_CIOCTRL_CIO_EN BIT(0)
+
#define DWC3_LLUCTL(n) (0xd024 + ((n) * 0x80))
/* Bit fields */
@@ -1309,6 +1314,7 @@ struct dwc3 {
#define DWC31_REVISION_170A 0x3137302a
#define DWC31_REVISION_180A 0x3138302a
#define DWC31_REVISION_190A 0x3139302a
+#define DWC31_REVISION_191A 0x3139312a
#define DWC31_REVISION_200A 0x3230302a
#define DWC32_REVISION_ANY 0x0
@@ -1653,11 +1659,23 @@ static inline void dwc3_pre_run_stop(struct dwc3 *dwc, bool is_on)
#if IS_ENABLED(CONFIG_USB_DWC3_HOST) || IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE)
int dwc3_host_init(struct dwc3 *dwc);
void dwc3_host_exit(struct dwc3 *dwc);
+
+/**
+ * dwc3_link_tunnel_mode - Check whether the link is tunneled over TBT/USB4
+ * @dwc: Pointer to DWC3 controller context
+ * @port: 0-based port index
+ *
+ * Returns: USB_LINK_TUNNELED if tunneled, USB_LINK_NATIVE if not, or
+ * when the controller does not have USB4 capabilities.
+ */
+enum usb_link_tunnel_mode dwc3_link_tunnel_mode(struct dwc3 *dwc, u8 port);
#else
static inline int dwc3_host_init(struct dwc3 *dwc)
{ return 0; }
static inline void dwc3_host_exit(struct dwc3 *dwc)
{ }
+static inline enum usb_link_tunnel_mode dwc3_link_tunnel_mode(struct dwc3 *dwc, u8 port)
+{ return USB_LINK_UNKNOWN; }
#endif
#if IS_ENABLED(CONFIG_USB_DWC3_GADGET) || IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE)
diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
index 96b588bd08cd..eb03b079696e 100644
--- a/drivers/usb/dwc3/host.c
+++ b/drivers/usb/dwc3/host.c
@@ -77,8 +77,20 @@ static void dwc3_xhci_plat_start(struct usb_hcd *hcd)
dwc3_enable_susphy(dwc, true);
}
+static enum usb_link_tunnel_mode dwc3_xhci_tunnel_mode(struct usb_hcd *hcd, int portnum)
+{
+ struct platform_device *pdev;
+ struct dwc3 *dwc;
+
+ pdev = to_platform_device(hcd->self.controller);
+ dwc = dev_get_drvdata(pdev->dev.parent);
+
+ return dwc3_link_tunnel_mode(dwc, portnum);
+}
+
static const struct xhci_plat_priv dwc3_xhci_plat_quirk = {
.plat_start = dwc3_xhci_plat_start,
+ .tunnel_mode = dwc3_xhci_tunnel_mode,
};
static void dwc3_host_fill_xhci_irq_res(struct dwc3 *dwc,
--
2.54.0
^ permalink raw reply related [flat|nested] 4+ messages in thread