Re: [PATCH 1/2] cxl/mbox: Add background operation handling machinery

[Davidlohr Bueso]

On Thu, 25 Aug 2022, Jonathan Cameron wrote:

> > +/*
> > + * Ensure that ->mbox_send() can run safely when a background
> > + * command is running. If so, returns zero, otherwise -EBUSY.
>
> As above, I'm not sure this is necessary given you should get
> a sensible error code in response to any such message.
> E.g. media disabled.

So this is necessary to prevent mischief in the polling case
where you can have windows where the driver is out of sync
with the hardware - hw finishes async command but driver
(sleeping poller) has not acknowledged this. In the irq case,
yeah this would be redundant and not needed.

Thanks,
Davidlohr