On Tue, Aug 16, 2022 at 4:57 PM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Tue, Aug 16, 2022 at 04:38:54PM +0800, Ray Chi wrote:
> > In general, xHCI didn't do anything for port initialization. However,
> > there are some requirement or limitation on various platforms, so
> > vendors need to do some error handlings if the device connected to a
> > broken USB accessory.
> >
> > This patch also add the hook to xhci_driver_overrides so that vendors
> > can add their specific protection easily if needed.
> >
> > Signed-off-by: Ray Chi <raychi@xxxxxxxxxx>
> > ---
> > drivers/usb/host/xhci.c | 17 +++++++++++++++++
> > drivers/usb/host/xhci.h | 1 +
> > 2 files changed, 18 insertions(+)
> >
> > diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
> > index 65858f607437..f237af9d6e2e 100644
> > --- a/drivers/usb/host/xhci.c
> > +++ b/drivers/usb/host/xhci.c
> > @@ -4358,6 +4358,20 @@ static int xhci_enable_device(struct usb_hcd *hcd, struct usb_device *udev)
> > return xhci_setup_device(hcd, udev, SETUP_CONTEXT_ONLY);
> > }
> >
> > +/*
> > + * The function could get the status of port initialization.
> > + */
> > +static int xhci_check_init_status(struct usb_hcd *hcd, struct usb_device *udev, int r)
> > +{
> > + /*
> > + * In general, this function is not necessory. Some platforms may
> > + * need doing error handling when the port initialization takes a
> > + * long time to do. The device can use the override callback to
> > + * do specific handlings.
> > + */
> > + return 0;
> > +}
>
> For obvious technical and legal reasons, we are not allowed to add
> "hooks" to the kernel where there are no in-kernel users. Nor would you
> want us to do so.
>
Agree on this. I am trying another way to achieve the same goal.
> So I really do not understand this patch series at all.
>
> What driver wants to do odd things here? What needs to happen that the
> in-tree drivers are not doing properly? Why not get the needed fixes in
> the in-kernel drivers instead of trying to add random hooks that some
> out-of-tree code would use instead.
>
> confused,
>
> greg k-h
I will prepare a new commit to do it.
Thanks,
Ray
