On Mon, Apr 11, 2016 at 02:28:08PM -0700, John Youn wrote: > On 4/8/2016 5:58 PM, Greg Kroah-Hartman wrote: > > On Fri, Apr 08, 2016 at 04:19:40PM -0700, John Youn wrote: > >> Hi, > >> > >> I'd like to request the following be applied to stable trees 3.2+. > >> > >> 1a85329171094951956a37acc8abb7e51c1e742e ("usb: gadget: composite: > >> Return bcdUSB 0x0310") > >> > >> The USB 3.1 specification replaces the USB 3.0 specification and all new > >> devices that are running at SuperSpeed or higher speeds must report a > >> bcdUSB of 0x0310. > > > > That doesn't seem very "backwards compatible" of the spec to me, what > > happens if you return a 3.0 string, when you really are only handling > > 3.0 things like we do in older kernels? > > > > thanks, > > > > greg k-h > > > > Hi Greg, > > I believe there would be no backward-incompatible change as all 3.0 > things are now part of the 3.1 spec, and the new stuff in 3.1 (such as > SuperSpeedPlus) are exposed through new descriptors. And I don't > believe anything currently looks at bcdUSB 3.0 vs 3.1 (unlike with USB > 2.x). But I can't say for sure. > > This is only needed because the CV tool has started requiring this and > I believe the compliance process will also start requiring it for all > new devices. We plan to certify new devices with kernels as old as > 3.18, hence this backport. For "new" devices, why are you using such an old and obsolete kernel as 3.18? For an "old" device, a bcdUSB of 3.0 should just be fine, right? > If you like, I can solicit comments on this from the linux-usb list. Please do, you need the maintainer of the subsystem to agree to this at the least :) thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html