On Sat, Jan 21, 2023 at 02:02:36AM +0000, Thinh Nguyen wrote: > On Fri, Jan 20, 2023, Alan Stern wrote: > > A UDC design might have multiple versions, some supporting remote wakeup > > and others not. But drivers generally use a single static > > usb_gadget_ops structure, and they don't modify it at runtime to account > > for hardware differences. So if a single driver controls those multiple > > versions, you can't rely on the presence of gadget->ops->wakeup to > > indicate whether there actually is hardware remote wakeup support. > > > > Ideally, the usb_gadget structure should have a wakeup_capable flag > > which the UDC driver would set appropriately (probably during its probe > > routine). > > > > I was thinking that it can be handled by the > usb_gadget_enable_remote_wakeup() so we can do away with the > wakeup_capable flag. usb_gadget_enable_remote_wakeup() gets called when the gadget or function is suspended, right? But a gadget driver may want to know long before that whether the UDC supports remote wakeup, in order to set up its config descriptor correctly. Alan Stern
