Re: [PATCH v2] usb: dwc2: Fix build in periphal-only mode

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Fri, May 28, 2021 at 10:37:48AM +0100, Phil Elwell wrote:
> Hi Greg,
> 
> On 28/05/2021 10:23, Greg Kroah-Hartman wrote:
> > On Fri, May 28, 2021 at 10:13:50AM +0100, Phil Elwell wrote:
> > > The bus_suspended member of struct dwc2_hsotg is only present in builds
> > > that support host-mode.
> > > 
> > > Fixes: 24d209dba5a3 ("usb: dwc2: Fix hibernation between host and device modes.")
> > > Signed-off-by: Phil Elwell <phil@raspberrypi.com>
> > > ---
> > >   drivers/usb/dwc2/core_intr.c | 4 ++++
> > >   1 file changed, 4 insertions(+)
> > > 
> > > v2: Correct commit hash used in the Fixes line.
> > > 
> > > diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c
> > > index a5ab03808da6..03d0c034cf57 100644
> > > --- a/drivers/usb/dwc2/core_intr.c
> > > +++ b/drivers/usb/dwc2/core_intr.c
> > > @@ -725,7 +725,11 @@ static inline void dwc_handle_gpwrdn_disc_det(struct dwc2_hsotg *hsotg,
> > >   	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
> > >   	hsotg->hibernated = 0;
> > > +
> > > +#if IS_ENABLED(CONFIG_USB_DWC2_HOST) ||	\
> > > +	IS_ENABLED(CONFIG_USB_DWC2_DUAL_ROLE)
> > >   	hsotg->bus_suspended = 0;
> > > +#endif
> > >   	if (gpwrdn & GPWRDN_IDSTS) {
> > >   		hsotg->op_state = OTG_STATE_B_PERIPHERAL;
> > > -- 
> > > 2.25.1
> > > 
> > 
> > I do not understand, the field in the structure is present for all, why
> > is this crazy #if needed here?
> > 
> > I see that the commit you reference here did add the new line to set
> > bus_suspended, which seemed to be the point here.  Why will the #if
> > values matter here?
> 
> Sorry to waste your brain cycles on this. There is a problem, but it only
> exists in branches where the blamed commit (24d209dba5a3) has been
> back-ported as a Fix, because it depends on commit 012466fc8ccc which isn't
> a Fix and therefore
> hasn't been back-ported. Sadly 012466fc8ccc doesn't back-port cleanly on its
> own - either more cherry-picks or a temporary patch like mine will be
> needed.

So should we revert this commit from the stable releases where it showed
up?  Which ones specifically?

If so, please let me and stable@vger.kernel.org know and we can take
care of it there.

thanks,

greg k-h