the intention of having two ttys pointing to the same cfe console device was.
Also we were not initializing the output[] array passed in as input to
tty_makedev() so one name of the ttys was garbage.
Fix the code that calls cfe_write() to deal with the case where only a partial
buffer is written out.
cfe_cngetc() needs to return if there is no character available as input.
If we don't do this then the cfe_timeout() function will spin forever
because cfe_cngetc() will only ever return if there is valid input.
Approved by: imp (mentor)
I don't want people to override the mutex when allocating a TTY. It has
to be there, to keep drivers like syscons happy. So I'm creating a
tty_alloc_mutex() which can be used in those cases. tty_alloc_mutex()
should eventually be removed.
The advantage of this approach, is that we can just remove a function,
without breaking the regular API in the future.
The cn_unit and cn_tp fields don't seem to be used anywhere. Some
drivers set them, while others don't. Just remove them, in an attempt to
make our consdev code a little easier to understand.
former more explicitly tells the compiler that you want an empty loop.
There are some lint programs that use this hint to avoid generating
warnings.
No functional change...
