mutexes

[Kamal R. Prasad]

hello,

i have 2 instances of an spi controller (pl022) on my setup. can someone
tell me :-
1. is there any danger if we interleave spi io transfers between these 2
controllers i.e  spi transfer starts on controller 0 and before it can
finish, controller 1 starts spi transfer. the 2 controllers have different
spi slave devices.
2. assuming there is an issue with that, how to setup a mutex in the code
path so that it is common to both instances of pl022 driver?

thanks
 -kamal