Hi! On Don, 2013-11-14 at 11:32 +0100, Luca Ellero wrote: [...] > can someone please show me which is the best practice to lock a > read/write to a hardware register. > In other words if, in a driver, I want to modify a bit in a HW register, > I have to read the register, set/reset the relevant bit and write back > the reg. > But what can I do to be sure that no other code modifies the register > between my read and write? > Is spin_lock() suitable for this purpose? If the read-modify-write (read: the critical section) run-time is short, a spin-lock is the usual means. If it is needed from IRQ-context - see also other mails - you must use the *_irq() variant. Bernd -- Bernd Petrovitsch Email : bernd@xxxxxxxxxxxxxxxxxxx LUGA : http://www.luga.at _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies