> > Yes, otherwise, the device which the udc is probed deferral and the > > gadget driver is build-in will never work. If we skip fixing it, this > > problem will exist for more than 2 years, it is too long. > > > > I have a support request from android team that usb peripheral > > function never works from 3.10.x kernel at one device, I think it is a > > common problem, no only I meet it. > > > > Below are links which this problem reports: > > > > http://marc.info/?l=linux-usb&m=139380872501745&w=2 > > http://marc.info/?l=linux-usb&m=137706435611447&w=2 > > > > > If you do want to fix the problem, there's a much easier way than > > > what you posted. See below. > > > > > Robert Baldyga posts the similar solution, but seems Felipe doesn't > > agree it. > > http://www.spinics.net/lists/linux-usb/msg102795.html > > > > Then, you and Felipe has a discussion for this problem: > > http://www.spinics.net/lists/linux-usb/msg106760.html > > Okay, I get it. Felipe didn't want to do this because you might end up > loading a gadget driver that never gets bound. There might not even be > any UDC devices at all. > > Felipe, I think the problem of having unbound gadget drivers isn't so bad. > It's just like having unbound drivers of any sort. For example, the > Fedora kernels have ohci-hcd and uhci-hcd built-in. Relatively few > systems have both OHCI and UHCI controllers (lots of current machines > have neither); everybody else ends up with at least one unused driver and > no way to remove it. If Fedora can do this, I think we can allow users > to have unnecessary gadget drivers. > > In fact, I don't know of any other kind of driver module whose init > routine will fail if there's no hardware to bind to. > > I suggest you go ahead and accept Robert Baldyga's original patch -- > except for one little problem: The patch forgets to add driver->list to > the global driver_list if the driver gets bound immediately. The > > list_add_tail(&driver->list, &driver_list); > > call needs to be moved up near the start of usb_gadget_probe_driver(). > Thanks, Alan. The another improvement is: set driver->attached as true at udc_bind_to_driver. Peter -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
