Hello, I think that how sanei_usb_open() collects endponts is not correct. It loops through all configurations, interfaces and alternate settings and takes the first bulk in, bulk out and interrupt endpoint it found. This works only for some special cases and it is likely to fail for multifunction devices, e.g. Smartbase MP360 which has endpoints for the scanner function in the interface #1.
I would propose that sanei_usb_open() accepts two additional parameters specifying an interface number and an alternate setting. These parameters can be omitted (e.g. set to -1). In this case the behaviour described above is valid. If the parameters are given, sanei_usb_open() must use only the endpoints belonging to the specified interface. There is also an issue with sanei_usb_set_configuration(), it simply doesn't work this way because setting new configuration will succeed if and only if there is no interfaces claimed by any driver. But the function takes the device number returned by sanei_usb_open() as a parameter and, unfortunely, sanei_usb_open() implicitly claims one interface. We have chicken and egg problem here. Solution: sanei_usb_set_configuration() have to take the device name instead of the device number as the first parameter. If I understand correctly, sanei_usb_claim_interface(), sanei_usb_release_interface() and sanei_usb_set_altinterface() are useless because sanei_usb_open() already claims an interface for you and sanei_usb_close() will release it afterward. Why does one want to claim another interface while he cannot use its endpoints through sanei_usb functions? Regards -- Wittawat Yamwong Hannover, Germany
