On Tue, Jul 27, 2021 at 03:24:28PM +0200, Oliver Neukum wrote: > > On 27.07.21 14:37, Chris wrote: > > This problem was introduced with 5.13 and still persists in 5.13.5 > > After downgrading to 5.12.x, everything works like expected. Tested on > > archlinux. The device is an "ICP-DAS I-7561" > this is almost certainly 8a7bf7510d1f43994b39a677e561af4ee6a1a0ae > > ("USB: serial: pl2303: amend and tighten type detection") Indeed. > Your device just says 0 everywhere: > > bDeviceClass 0 > bDeviceSubClass 0 > bDeviceProtocol 0 This is expected. The protocol is per-interface, and nothing besides the bcdVersion really stands out in the report. > We could add a default type, but does that make sense? Yeah, we may need to fallback to something like HX type if turns out that there are more devices out there with unexpected bcdDevice. Johan