Re: [PATCH] iwlwifi: remove input device and fix rfkill state

[Zhu Yi <yi.zhu@intel.com>]

On Tue, 2008-07-01 at 13:56 -0300, Henrique de Moraes Holschuh wrote:
> On Tue, 01 Jul 2008, Adel Gadllah wrote:
> > The calls to iwl|iwl3945_rfkill_set_hw_state() had to be moved
> because rfkill_force_state() cannot be called from an atomic context.

Yes, but what your patch changed is not in the atomic context. It is
just inside the driver's priv->mutex. I don't see any problem if you
call rfkill_force_state() inside it.

> Yeah, the joys of mutexes.  If this is going to be a severe annoyance
> to drivers, I don't see why rfkill could not be changed to use some
> other locking primitive that does work on atomic contexes.

Allowing rfkill_force_state() to be called in the atomic context would
be useful especially for hardware rfkill. Devices (i.e iwl4965) receive
an interrupt when the hw-rfkill state changes. It's natural to update
the rfkill state in this context.

How about protect the rfkill->state by a spinlock and put the
notifier_call_chain() into a workqueue in the rfkill subsystem?

Thanks,
-yi