On Fri, Mar 15, 2019 at 05:13:24PM +0800, Chunfeng Yun wrote: > I encounter a build error when CONFIG_USB_ROLE_SWITCH is not enabled, > > drivers/usb/mtu3/mtu3_dr.o: In function `ssusb_role_sw_register': > ./drivers/usb/mtu3/mtu3_dr.c:460: undefined reference to > `usb_role_switch_register' > drivers/usb/mtu3/mtu3_dr.o: In function `ssusb_otg_switch_exit': > ./drivers/usb/mtu3/mtu3_dr.c:491: undefined reference to > `usb_role_switch_unregister' > > the following patch has fixed the issue, but seems not get into kernel, > [v3,08/12] usb: roles: Add usb role switch notifier. > https://patchwork.kernel.org/patch/10836525/ > > What should I do if I add a new API? Thanks So if you are asking should you supply dummy functions for the new API, then I would just say that if you do so, you need to prepare these patches on top of that series from Yu Chen. In general I'm not sure we need dummy functions with this API. Hans, comments? thanks, -- heikki
