Re: [PATCH] usb: dwc3: gadget: Inform system of suspended state

From: Thinh Nguyen
Date: Mon Jun 03 2024 - 21:03:36 EST


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?

Thanks,
Thinh

>
> Signed-off-by: Mike Looijmans <mike.looijmans@xxxxxxxx>
> ---
>
> drivers/usb/dwc3/gadget.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 4df2661f6675..99e8ea9db600 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -4343,6 +4343,7 @@ static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
> if (!dwc->suspended && next == DWC3_LINK_STATE_U3) {
> dwc->suspended = true;
> dwc3_suspend_gadget(dwc);
> + usb_gadget_set_state(dwc->gadget, USB_STATE_SUSPENDED);
> }
>
> dwc->link_state = next;
> --
> 2.34.1
>
>
> Met vriendelijke groet / kind regards,
>
> Mike Looijmans
> System Expert
>
>
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