[PATCH] Add missing link states in dwc3 gadget wakeup

[PATCH] Add missing link states in dwc3 gadget wakeup

[Marcel Hamer]

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

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

[Marcel Hamer]

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
> 

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

[Greg KH]

On Fri, Apr 23, 2021 at 04:40:08PM +0200, Marcel Hamer wrote:
> 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.

When submitting patches, please use scripts/get_maintainers.pl to know
who to cc: so that they know to pay attention to your commit.  Care to
do that again here and resend it?

Also, you might want to change your subject line to match up with others
for this driver:
	[PATCH] USB: dwc3: add missing link...

thanks,

greg k-h

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

[Marcel Hamer]

On Fri, Apr 23, 2021 at 05:04:35PM +0200, Greg KH wrote:
> On Fri, Apr 23, 2021 at 04:40:08PM +0200, Marcel Hamer wrote:
> > 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.
> 
> When submitting patches, please use scripts/get_maintainers.pl to know
> who to cc: so that they know to pay attention to your commit.  Care to
> do that again here and resend it?
> 
> Also, you might want to change your subject line to match up with others
> for this driver:
> 	[PATCH] USB: dwc3: add missing link...
> 
> thanks,
> 
> greg k-h

Absolutely, will resend it. Thanks for the information.

Marcel