On 18 February 2014 10:21, Peter Stuge <peter@xxxxxxxx> wrote: > Clinton Sprain wrote: >> I noticed your examples are both fn combos. I'm seeing something like >> this and it seems specifically related to the fn key. Reproducible on a >> Macbook (3,1) and a Lenovo Yoga 13. Sequence is simple: >> >> Press key >> Press fn >> Release key >> Release fn >> >> The key will be 'stuck' until you press another key. It seems to only >> apply to keys that are part of a fn combo > > Fn is handled by the embedded controller (H8 as per Intel reference > design in case of Macbook or Thinkpad) which has its own closed > firmware which is rarely perfectly bug-free. The likelyhood that the root-cause was in an embedded controller was holding me back from reporting it. I believe the Mac keyboards use the generic HID driver in Windows, so it may be that there isn't a device-specific workaround, but maybe a generic workaround, though I can't reason the mechanism without more input-stack-fu. I guess one test hack to confirm our sanity would be to re-read the key state every 100ms until a matching key-up is received, logging when it detects a disparity between key state and no key-up received...? -- Daniel J Blueman -- 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
