Re: [PATCH v2] usbip: convert to use faux_device

[Zongmin Zhou]

On 2025/6/19 19:01, Greg KH wrote:
> On Wed, Jun 04, 2025 at 02:54:10PM +0800, Zongmin Zhou wrote:
> > From: Zongmin Zhou <zhouzongmin@xxxxxxxxxx>
> >
> > The vhci driver does not need to create a platform device,
> > it only did so because it was simple to do that in order to
> > get a place in sysfs to hang some device-specific attributes.
> > Now the faux device interface is more appropriate,change it
> > over to use the faux bus instead.
> >
> > Signed-off-by: Zongmin Zhou <zhouzongmin@xxxxxxxxxx>
> > ---
> > Changes in v2:
> > - don't change faux create api,just call probe on vhci_hcd_init.
> >
> >   drivers/usb/usbip/vhci.h             |  4 +-
> >   drivers/usb/usbip/vhci_hcd.c         | 86 +++++++++++-----------------
> >   drivers/usb/usbip/vhci_sysfs.c       | 68 +++++++++++-----------
> >   tools/usb/usbip/libsrc/vhci_driver.h |  2 +-
> >   4 files changed, 72 insertions(+), 88 deletions(-)
> I get the following build errors from this patch:
>
> drivers/usb/usbip/vhci_hcd.c:1462:12: error: ‘vhci_hcd_resume’ defined but not used [-Werror=unused-function]
>   1462 | static int vhci_hcd_resume(struct faux_device *fdev)
>        |            ^~~~~~~~~~~~~~~
> drivers/usb/usbip/vhci_hcd.c:1418:12: error: ‘vhci_hcd_suspend’ defined but not used [-Werror=unused-function]
>   1418 | static int vhci_hcd_suspend(struct faux_device *fdev, pm_message_t state)
>        |            ^~~~~~~~~~~~~~~~
> cc1: all warnings being treated as errors
>
> Are you sure you tested this?
I apologize for not enabling -Werror, which resulted in missing this 
error warning.
I have tested usbip feature use the new patch,but not test system 
suspend/resume.
The faux bus type don't add pm function,and vhci-hcd driver can't 
register it.
Maybe have to add suspend/resume for it.like below:
static const struct bus_type faux_bus_type = {
    .name        = "faux",
    .match        = faux_match,
    .probe        = faux_probe,
    .remove        = faux_remove,
    .resume     = faux_resume,
    .suspend    = faux_suspend,
};

Is that right?
Your expertise would be greatly valued.
Thanks very much.
> thanks,
>
> greg k-h