On Sat, Jan 21, 2023 at 12:21:10AM +0000, Thinh Nguyen wrote: > The way gadget->rw_capable is named and described, it's a capability > flag. That is, its value shouldn't change from the user config. Perhaps > we don't need that in the usb_gadget, and we can have something that > looks like this: > > if (gadget->ops->wakeup && (c->bmAttributes & USB_CONFIG_ATT_WAKEUP)) > usb_gadget_enable_remote_wakeup(g); > else > usb_gadget_disable_remote_wakeup(g); > > The setting of the remote wakeup configuration can be tracked internally > by the dwc3 driver based on the usb_gadget_enable_remote_wakeup call. 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). Alan Stern
