On Fri, Oct 8, 2010 at 1:12 AM, Roger Quadros <roger.quadros@xxxxxxxxx> wrote: > Hi, > > On 10/07/2010 07:34 PM, ext Brett Werling wrote: >> >> Does anyone know what the status is on the requirement of the MS OS >> Descriptor? > > > I don't think MS OS descriptor is required any more since now MTP is an > approved USB Class. i.e. it has to use the PTP Class code. > > The host should identify if the PTP device supports MTP extensions and > identify the device as MTP. > > However, if you fail to use MS OS descriptor, leagcy Windows OS'es will > identify your device as PTP only, unless you supply a .inf file to load the > MTP drivers for your device. Will my device appear to the hose as a PTP device then? What can be done if I only want to support MTP and then fall back to MSC? i.e. - I'd rather not have a prompt saying my device is a digital still camera or something along these lines. > > I can confirm that OS descriptors is not required for Windows 7 at least. It > correctly identifies an MTP device. And OS descriptors may have some legal > chains tied to it. > http://www.microsoft.com/whdc/connect/usb/os_desc.mspx > >> I'm trying to determine what the best course of action is >> for determining if a host supports MTP. >> > > If you get a set configuration request it means the host most likely > supports it. Don't depend on these OS descriptor requests for this. Non > Windows OS'es will not request it. I've noticed some devices that I've tested used the vendor specific interface device class, and yet Win 7 and Win XP didn't ask for an OS descriptor. Is this possibly because Windows recognizes the manufacturer/model and knows to load the proper MTP driver? > > -- > regards, > -roger > Thanks, Brett -- 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
