Hello, Janusz Krzysztofik, le Tue 14 Jul 2009 17:31:23 +0200, a écrit : > In my attempt to add support for contols to a voice modem codec sound > device driver, I found that in order to talk to the modem, it would be > convenient if I can get access to a tty device from inside the kernel in > a way similiar to that available form userspace. I agree. > AFAICS, even if tty lowlevel write() could be used unmodified, a > convenient way of reading characters from a tty is missing and should > be implemented in a line discipline. Please correct me if I am wrong. Have you seen the receive_buf line discipline hook? Indeed it's not a read() operation as from userland, but at least you can get the data from the tty that way. > OTOH, I found that some kind of abstraction layer for acccessing devices > over a tty could be convenient. Instead of allocating a new line > discipline for each specific device, sometimes found on a specific board > only, why not just create a new bus type? I'd tend to agree with you, as I also have a use case for that: braille & speech synthesis devices. However for now I haven't found a really convincing argument why line disciplines aren't enough. Samuel _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
