On 05-06-2024 01:06, Thinh Nguyen wrote:
Hi,
On Tue, Jun 04, 2024, Mike Looijmans wrote:
On 04-06-2024 03:03, Thinh Nguyen wrote:
Hi,
On Mon, Jun 03, 2024, Mike Looijmans wrote:
When disconnecting the USB cable on an LS1028 device, nothing happens
in userspace, which keeps thinking everything is still up and running.
Turns out that the DWC3 controller only sends DWC3_DEVICE_EVENT_SUSPEND
in that case, and not a DWC3_DEVICE_EVENT_DISCONNECT as one would
expect. As a result, sysfs attribute "state" remains "configured"
until something resets it.
Forward the "suspended" state to sysfs, so that the "state" at least
changes into "suspended" when one removes the cable, and hence also
matches the gadget's state when really suspended.
On disconnection, did you see disconnect interrupt? If so, it should
transition to USB_STATE_NOATTACHED. This change doesn't seem to directly
address your issue. Can you provide the driver tracepoints?
The device doesn't issue a disconnect event, I didn't have tracing enabled
in the kernel but added some dev_info() calls to determine what was going
on. Added this to dwc3_process_event_entry():
dev_info(dwc->dev, "event: 0x%x type=0x%x", event->raw, event->type.type);
When disconnecting the cable from the host, I see this:
[ 50.841411] dwc3 3110000.usb: event: 0x6084 type=0x42
[ 50.841457] dwc3 3110000.usb: event: 0x4086 type=0x43
[ 50.841494] dwc3 3110000.usb: event: 0x6084 type=0x42
[ 50.841534] dwc3 3110000.usb: event: 0x4086 type=0x43
[ 50.841571] dwc3 3110000.usb: event: 0x4086 type=0x43
[ 52.650990] dwc3 3110000.usb: event: 0x30601 type=0x0
The "0x4086" and "0x6084" messages are endpoint events that occur all the
time while connected. The last event is the "suspend" one. After that, total
silence.
If you need traces, please point me to a description on how to obtain them.
Let me know if you run into issues following this instructions to
capture the tracepoints:
https://docs.kernel.org/driver-api/usb/dwc3.html#required-information
From the patch you provided, you only apply the change for the usb
suspend. But did your device go through system suspend? If that's the
case, then the dwc3 driver will cause a soft-disconnect. Currently that
will not prompt a state change. We need the tracepoint to know more
detail.
Until we have the tracepoints, you can experiment with this test patch.
If my suspiction is correct, then this may resolve your issue:
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 89fc690fdf34..29dbb889a0e2 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2682,6 +2682,8 @@ static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
*/
ret = dwc3_gadget_run_stop(dwc, false);
+ usb_gadget_set_state(dwc->gadget, USB_STATE_NOTATTACHED);
+
/*
* Stop the gadget after controller is halted, so that if needed, the
* events to update EP0 state can still occur while the run/stop
I tried the patch above, but it doesn't work. Apparently
dwc3_gadget_soft_disconnect() doesn't get called when I unplug the cable.
--
Mike Looijmans
System Expert
TOPIC Embedded Products B.V.
Materiaalweg 4, 5681 RJ Best
The Netherlands
T: +31 (0) 499 33 69 69
E: mike.looijmans@xxxxxxxx
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