okash.khawaja@xxxxxxxxx, on dim. 12 mars 2017 12:16:45 +0000, wrote: > Allow access to TTY device from kernel. This is based on Alan Cox's patch > (http://www.mail-archive.com/linux-kernel at vger.kernel.org/msg1215095.html), > with description quoted below. > > "tty_port: allow a port to be opened with a tty that has no file handle > > Let us create tty objects entirely in kernel space. > > With this a kernel created non file backed tty object could be used to handle > data, and set terminal modes. Not all ldiscs can cope with this as N_TTY in > particular has to work back to the fs/tty layer. > > The tty_port code is however otherwise clean of file handles as far as I can > tell as is the low level tty port write path used by the ldisc, the > configuration low level interfaces and most of the ldiscs. > > Currently you don't have any exposure to see tty hangups because those are > built around the file layer. However a) it's a fixed port so you probably > don't care about that b) if you do we can add a callback and c) you almost > certainly don't want the userspace tear down/rebuild behaviour anyway. > > This should however be sufficient if we wanted for example to enumerate all > the bluetooth bound fixed ports via ACPI and make them directly available. > > It doesn't deal with the case of a user opening a port that's also kernel > opened and that would need some locking out (so it returned EBUSY if bound > to a kernel device of some kind). That needs resolving along with how you > "up" or "down" your new bluetooth device, or enumerate it while providing > the existing tty API to avoid regressions (and to debug)." > > Signed-off-by: Okash Khawaja <okash.khawaja@xxxxxxxxx> When you receive a Reviewed-by: Samuel Thibault <samuel.thibault@xxxxxxxxxxxx> do include it in your patch, so that when you re-send the series, it has it already for people to know that it has been reviewed. Samuel _______________________________________________ Speakup mailing list Speakup@xxxxxxxxxxxxxxxxx http://linux-speakup.org/cgi-bin/mailman/listinfo/speakup
