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Description of problem: my self-tinkered chorded keyboard does not deliver key press/release messages with 2.6.40-4.fc15, although it works fine with 2.6.38.8-35.fc15. on another box (atom N270 (i686)) i have the same problem with another ACM device (self-tinkered) and 2 USB DVB-T TV sticks (vendor: Hauppauge). Version-Release number of selected component (if applicable): 2.6.40-4.fc15 How reproducible: always Steps to Reproduce: 1. reboot 2. start a program that reads from /dev/ttyACM0 Actual results: open works as before, but nothing is read. Expected results: there should be some incoming data. Additional info: i found it remarkable, that it fails on 2 boxes, 2 architectures and 2 USB devices.
with 2.6.40.3-0 i still have those problems... on i686 it crashes after a few minutes (no ethernet access... it is head-less, so that i cant c any special error messages...)... -arne
2.6.40.4-5.fc15.x86_64 still doesnt like my USB device... -arne
2.6.40.6-0.fc15.x86_64 still doesnt treat my ttyACM devices as before... i had a closer look at it, and now it seems, that it holds back a byte in some buffer, so that a read fails... when a write a further byte, the following read delivers the byte that i expected before... i think that is a bug in the ACM or USB buffer handling, because: there is no guarantee that there is an infinitely long data stream coming from a serial port... -arne
You should probably email upstream about this. We don't have the hardware to recreate issues and thus far you're the only person reporting a problem.
at linux-kernel mailing list they suggested that the fedora-patches might have caused the trouble... i could falsify that theory (i used the fc15 kernel SRPM for 2.6.40.6-0 and hacked the SPECS file so that it would be a vanilla kernel (kernel-vanilla-2.6.40.6-0.local.fc15.x86_64.rpm))... furthermore i gave them some usbmon traces some days ago, but nobody replied yet (maybe they r angry, because i forgot the subject line once...)... a communication that works with both kernels (it is just about 1msec long): http://www.wgboome.org/cmd:P-C,2.6.40.6-0.local.fc15.x86_64.usbmon a communication that works with the 2.6.38.8 kernel but not the 2.6.40 kernel (it has a 50msec pause in the middle, where no USB stuff can be done... my self-tinkered-usb-device talks to some other device in that time, which takes its full concentration... but it is still a bug, that 1 byte hangs in some buffer, i think...): http://www.wgboome.org/cmd:Z-L-0,2.6.38.8-35.fc15.x86_64.usbmon http://www.wgboome.org/cmd:Z-L-0,1st-try,2.6.40.6-0.fc15.x86_64.usbmon http://www.wgboome.org/cmd:Z-L-0,2nd-try,2.6.40.6-0.fc15.x86_64.usbmon http://www.wgboome.org/cmd:Z-L-0,2nd-try,2.6.40.6-0.local.fc15.x86_64.usbmon -arne
yesterday i made my self tinkered USB device more USB compliant... since then the current 2.6.41 kernel works fine... the TV sticks work fine again, 2... :-) -arne