Re: dwc3 gadget: controller stop times out on system sleep

[Thinh Nguyen]

Hi,

On Wed, Apr 26, 2023, Roger Quadros wrote:
> Hi Thinh,
> 
> On Linux kernel v6.3
> Test procedure: 
> 
> - modprobe g_zero
> - Connect to PC host
> - systemctl suspend
> 
> A large delay of 3 seconds is observed. The delay comes from dwc3_gadget_suspend()->dwc3_gadget_run_stop() waiting for DWC3_DSTS_DEVCTRLHLT to be set.
> It returns -ETIMEDOUT.
> 
> Are we missing something to do a clean stop during suspend?
> 
> FYI. Unloading g_zero does not show this delay on stop.
> 
> cheers,
> -roger

When clearing run_stop bit and the controller doesn't halt, that usually
means there are active transfers/endpoints that aren't ended yet.

The dwc3_gadget_suspend() doesn't properly do all the cleanup before
clearing the run_stop bit. I think you just need to call
dwc3_gadget_soft_disconnect() in dwc3_gadget_suspend() to fix this.

Thanks,
Thinh