On Tue, Feb 03, 2026, Peng Fan wrote:

On Tue, Feb 03, 2026 at 12:24:08AM +0000, Thinh Nguyen wrote:

quoted

On Mon, Feb 02, 2026, Xu Yang wrote:

quoted

The current design assumes that the controller remains powered
when wakeup is enabled. However, some SoCs provide wakeup
capability even when the controller itself is powered down, using
separate dedicated wakeup logic. This allows additional power
savings, but requires the controller to be fully re‑initialized
after system resume.

To support these SoCs, introduce a flag to track the controller’s
power state and use it throughout the suspend/resume flow.

Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
---
 drivers/usb/dwc3/core.c | 9 +++++++--
 drivers/usb/dwc3/core.h | 2 ++
 drivers/usb/dwc3/glue.h | 3 +++
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index c07ffe82c85049364c38c7ba152aab0ff764d95e..9d4326da5ec7669fa714707fb24556723cab51b8 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c

@@ -2314,6 +2314,9 @@ int dwc3_core_probe(const struct dwc3_probe_data *data)
 			goto err_exit_debugfs;
 	}
 
+	if (data->core_may_lose_power)

Can this be passed down as part of the dwc3_properties within the
probe_data? I'm trying to consolidate all the dwc3 properties to one
place.

quoted

+		dwc->may_lose_power = true;
+
 	pm_runtime_put(dev);
 
 	dma_set_max_seg_size(dev, UINT_MAX);

@@ -2462,7 +2465,8 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
 		dwc3_core_exit(dwc);
 		break;
 	case DWC3_GCTL_PRTCAP_HOST:
-		if (!PMSG_IS_AUTO(msg) && !device_may_wakeup(dwc->dev)) {
+		if (!PMSG_IS_AUTO(msg) &&
+		    (!device_may_wakeup(dwc->dev) || dwc->may_lose_power)) {
 			dwc3_core_exit(dwc);
 			break;
 		}

@@ -2525,7 +2529,8 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
 		dwc3_gadget_resume(dwc);
 		break;
 	case DWC3_GCTL_PRTCAP_HOST:
-		if (!PMSG_IS_AUTO(msg) && !device_may_wakeup(dwc->dev)) {
+		if (!PMSG_IS_AUTO(msg) &&
+		    (!device_may_wakeup(dwc->dev) || dwc->may_lose_power)) {
 			ret = dwc3_core_init_for_resume(dwc);
 			if (ret)
 				return ret;

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 08cc6f2b5c23631a752c77fd7394e5876c929f0a..5b1358f36490a001bc9e68139224f7be70a57995 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h

@@ -1117,6 +1117,7 @@ struct dwc3_glue_ops {
  * @usb3_lpm_capable: set if hadrware supports Link Power Management
  * @usb2_lpm_disable: set to disable usb2 lpm for host
  * @usb2_gadget_lpm_disable: set to disable usb2 lpm for gadget
+ * @may_lose_power: set to indicate the core may lose power during pm suspend
  * @disable_scramble_quirk: set if we enable the disable scramble quirk
  * @u2exit_lfps_quirk: set if we enable u2exit lfps quirk
  * @u2ss_inp3_quirk: set if we enable P3 OK for U2/SS Inactive quirk

@@ -1369,6 +1370,7 @@ struct dwc3 {
 	unsigned		usb3_lpm_capable:1;
 	unsigned		usb2_lpm_disable:1;
 	unsigned		usb2_gadget_lpm_disable:1;
+	unsigned		may_lose_power:1;

This name sounds like a quirk of a broken SoC.

Perhaps rename this to something such as power_lost_on_suspend or
needs_full_reinit?

How about out_band_wakeup?

IMHO, it's not as clear. It doesn't describe the problem or the action
to take. Can we use needs_full_reinit?

Thanks,
Thinh