Greg KH wrote: > On Tue, Dec 19, 2006 at 11:00:26AM +0800, [EMAIL PROTECTED] wrote: >> Hi, >> We have a USB audio device's product. I want to control speak's volume >> with HID(i.e. use external button), but the function in Linux is >> not available. I searched some about that in Internet and >> found that "Linux (at the operating system kernel level) supports >> four interfaces to a HID device - keyboard, mouse, joystick and a >> generic interface, known as the event interface". Does it mean >> Audio's HID is not support? Please give me some comments. Thanks. > > Can you attach the output of 'lsusb -v' run as root with your device > plugged in? There is already a USB audio class, and I wasn't aware of > any HID specific Audio stuff, but as the HID spec is a mess, I would not > be surprised :) > > thanks, > > greg k-h >
You might be running into a problem I have with the /dev/usb/hiddev0 It filters out duplicate messages from the usb device. I posted a patch some time ago, and people on this list just said, "Well, maybe we should look into this." So, if you have an up volume button and a down volume button: Pressing up,down outputs at hiddev0 up,down Pressing up,up outputs at hiddev0 up Pressing down,down,down,down outputs at hiddev0 just one down. This would kind of kill your volume control application. Do you see any output from /dev/usb/hiddev0 ? James ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
