On 2012.07.19 15:06, Markus wrote: > The Windows System Information reports the uPD720200 HC (driver > 2.1.36, FW 4015) as PCI\VEN_1033&DEV_0194, and its root hub as > NUSB3\ROOT_HUB30&VID_1033&PID_0194. The PID resolves to "Nucam Corp." > in libusbx, which is plain wrong.
Well the thing is, the HW id provided by the Renesas driver in the Device Manager (Renesas Electronics USB 3.0 root hub) is indeed NUSB3\ROOT_HUB30&VID_1033&PID_0194, which is the Renesas equivalent of the USB\ROOT_HUB&VID8086&PID28XX that Microsoft reports for Intel root hubs. Oh, and these values are likely to change in Windows 8, since Microsoft will be the purveyor of the driver (I think it reverts to using USB as a prefix). The design decision I took, after trying it the other way, is to be as close as possible to what the OS reports. This is because, IMO, the expectation most users will have for root hubs, will be for libusbx to report IDs that match the ones get in Device Manager. > Any opinions except "don't look at root hubs at all"? My opinion is: follow the OS. That's what the other platforms seem to do, and this is also what we do on Windows. If the OS takes liberties with VID:PID assignations, and uses an exception for root hubs, then we follow suit. > As for the root hubs, I agree with Pete; however, the VID/PID > assignment has to be thought through since it won't be correct > in most cases (i.e. if the PCI and USB VID are not identical for > a given manufacturer) In that case, you may want to report that issue to Microsoft and Renesas, as we're following their lead. Or if there's a strong vote for it, the one option I can rally with would be to follow the Linux model, but use 045E (Microsoft Corp.) rather than 1D6B (Linux Foundation) for the VID. Still, I would prefer keeping libusbx from introducing a custom scheme that our users may need to be aware of, and that doesn't match anything they would have previously seen. On the other hand, I have no problem adding something like the following in our documentation: "Be mindful that the VID:PID reported for root hubs on Windows are PCI subsystem ones rather than USB ones, as we follow what the Device Manager does." Regards, /Pete ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ libusbx-devel mailing list libusbx-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libusbx-devel
