Best practice to lock a read/write to a HW register

[Mandeep Sandhu]

On Thu, Nov 14, 2013 at 4:02 PM, Luca Ellero <lroluk at gmail.com> wrote:
> Hi all,
> 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 IRQ handlers can touch this register, then I think you'll have to
disable interrupts as well (spin_lock_irq*() ?).

HTH,
-mandep

> Thanks
> Best regards
> Luca
>
>
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