Re: [PATCH] Add missing link states in dwc3 gadget wakeup

[Marcel Hamer <marcel@solidxs.nl>]

Hello,

I would like to add that I do not have the dwc3 documentation myself,
given it is not publically available. I deduced the patch from active 
debugging on my system.

Please let me know if DWC3_LINK_STATE_U1 and DWC3_LINK_STATE_U2 should
either be removed from the 'needs_wakeup =' line instead. Or if
something else is off with the proposed patch.

Kind regards,

Marcel

On Fri, Apr 23, 2021 at 03:23:14PM +0200, Marcel Hamer wrote:
> In dwc3_send_gadget_ep_cmd() a check is performed if the gadget needs
> waking up. The following condition is checked before calling the
> __dwc3_gadget_wakeup() function:
> 
> 	needs_wakeup = (dwc->link_state == DWC3_LINK_STATE_U1 ||
>         		dwc->link_state == DWC3_LINK_STATE_U2 ||
>                         dwc->link_state == DWC3_LINK_STATE_U3);
> 
> Inside __dwc3_gadget_wakeup() only link_state DWC3_LINK_STATE_U3 is checked
> and link state DWC3_LINK_STATE_U1 and DWC3_LINK_STATE_U2 are considered
> invalid and generate a warning becaus of the call to:
> 
> dev_WARN_ONCE(dwc->dev, ret, "wakeup failed --> %d\n", ret);
> 
> because of ret being -EINVAL.
> 
> Signed-off-by: Marcel Hamer <marcel@solidxs.se>
> ---
>  drivers/usb/dwc3/gadget.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index c7ef218e7a8c..d05a7d630410 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -1972,6 +1972,8 @@ static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
>  	switch (link_state) {
>  	case DWC3_LINK_STATE_RESET:
>  	case DWC3_LINK_STATE_RX_DET:	/* in HS, means Early Suspend */
> +	case DWC3_LINK_STATE_U1:
> +	case DWC3_LINK_STATE_U2:
>  	case DWC3_LINK_STATE_U3:	/* in HS, means SUSPEND */
>  	case DWC3_LINK_STATE_RESUME:
>  		break;
> -- 
> 2.25.1
>