On Tue, May 28, 2024, Xu Yang wrote:
> In current design, spin_lock_irqsave() will run twice when suspend gadget
> device if the controller is using OTG block:
>
> dwc3_suspend_common()
> spin_lock_irqsave(&dwc->lock, flags); <-- 1st
> dwc3_gadget_suspend(dwc);
> dwc3_gadget_soft_disconnect(dwc);
> spin_lock_irqsave(&dwc->lock, flags); <-- 2nd
>
> This will cause deadlock on the suspend path. To let it work, just remove
> spin_lock/unlock_* in dwc3_suspend_common() since they are redundant.
>
> Fixes: 5265397f9442 ("usb: dwc3: Remove DWC3 locking during gadget suspend/resume")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx>
>
> ---
> Changes in v2:
> - add fix tag and stable list
> ---
> drivers/usb/dwc3/core.c | 3 ---
> 1 file changed, 3 deletions(-)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 7ee61a89520b..b8193edc41bd 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -2250,7 +2250,6 @@ static int dwc3_core_init_for_resume(struct dwc3 *dwc)
>
> static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
> {
> - unsigned long flags;
> u32 reg;
> int i;
>
> @@ -2293,9 +2292,7 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
> break;
>
> if (dwc->current_otg_role == DWC3_OTG_ROLE_DEVICE) {
> - spin_lock_irqsave(&dwc->lock, flags);
> dwc3_gadget_suspend(dwc);
> - spin_unlock_irqrestore(&dwc->lock, flags);
> synchronize_irq(dwc->irq_gadget);
> }
>
> --
> 2.34.1
>
Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
Thanks,
Thinh
