Currently we process the suspend interrupt event only if the
device is in configured state. Consider a case where device
is not configured and got suspend interrupt, in that case our
gadget will still use 100mA as composite_suspend didn't happen.
But battery charging specification (BC1.2) expects a downstream
device to draw less than 2.5mA when unconnected OR suspended.

Fix this by removing the condition for processing suspend event,
and thus composite_resume would set vbus draw to 2.

Fixes: 72704f876f50 ("dwc3: gadget: Implement the suspend entry event handler")
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
---
 drivers/usb/dwc3/gadget.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 89dcfac..a83f34e 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -4241,15 +4241,8 @@ static void dwc3_gadget_interrupt(struct dwc3 *dwc,
 		break;
 	case DWC3_DEVICE_EVENT_SUSPEND:
 		/* It changed to be suspend event for version 2.30a and above */
-		if (!DWC3_VER_IS_PRIOR(DWC3, 230A)) {
-			/*
-			 * Ignore suspend event until the gadget enters into
-			 * USB_STATE_CONFIGURED state.
-			 */
-			if (dwc->gadget->state >= USB_STATE_CONFIGURED)
-				dwc3_gadget_suspend_interrupt(dwc,
-						event->event_info);
-		}
+		if (!DWC3_VER_IS_PRIOR(DWC3, 230A))
+			dwc3_gadget_suspend_interrupt(dwc, event->event_info);
 		break;
 	case DWC3_DEVICE_EVENT_SOF:
 	case DWC3_DEVICE_EVENT_ERRATIC_ERROR:
-- 
2.7.4

On Thu, Feb 23, 2023, Prashanth K wrote:
> Currently we process the suspend interrupt event only if the
> device is in configured state. Consider a case where device
> is not configured and got suspend interrupt, in that case our
> gadget will still use 100mA as composite_suspend didn't happen.
> But battery charging specification (BC1.2) expects a downstream
> device to draw less than 2.5mA when unconnected OR suspended.
> 
> Fix this by removing the condition for processing suspend event,
> and thus composite_resume would set vbus draw to 2.
> 
> Fixes: 72704f876f50 ("dwc3: gadget: Implement the suspend entry event handler")
> Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
> ---
>  drivers/usb/dwc3/gadget.c | 11 ++---------
>  1 file changed, 2 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 89dcfac..a83f34e 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -4241,15 +4241,8 @@ static void dwc3_gadget_interrupt(struct dwc3 *dwc,
>  		break;
>  	case DWC3_DEVICE_EVENT_SUSPEND:
>  		/* It changed to be suspend event for version 2.30a and above */
> -		if (!DWC3_VER_IS_PRIOR(DWC3, 230A)) {
> -			/*
> -			 * Ignore suspend event until the gadget enters into
> -			 * USB_STATE_CONFIGURED state.
> -			 */
> -			if (dwc->gadget->state >= USB_STATE_CONFIGURED)
> -				dwc3_gadget_suspend_interrupt(dwc,
> -						event->event_info);
> -		}
> +		if (!DWC3_VER_IS_PRIOR(DWC3, 230A))
> +			dwc3_gadget_suspend_interrupt(dwc, event->event_info);
>  		break;
>  	case DWC3_DEVICE_EVENT_SOF:
>  	case DWC3_DEVICE_EVENT_ERRATIC_ERROR:
> -- 
> 2.7.4
> 

Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>

Thanks,
Thinh