> - Handle the global mutex properly when rfkill_set_{hw,sw}_state()
> or
> rfkill_set_states() is called from within an rfkill callback. v2
> always tried to lock the global mutex in such a case, which led
> to a
> deadlock when an rfkill driver called one of the above functions
> from its query or set_block callback. This is solved by defining
> a
> new bitfield, RFKILL_BLOCK_SW_HASLOCK, which is set before the
> above
> callbacks are invoked and cleared afterwards; the functions
> listed
> above use this bitfield to tell rfkill_any_led_trigger_event()
> whether the global mutex is currently held or not.
> RFKILL_BLOCK_SW_SETCALL cannot be reused for this purpose as
> setting
> it before invoking the query callback would cause any calls to
> rfkill_set_sw_state() made from within that callback to work on
> RFKILL_BLOCK_SW_PREV instead of RFKILL_BLOCK_SW and thus change
> the
> way rfkill_set_block() behaves.
I'm not super happy with this conditional locking - can't we instead
defer the necessary work to a workqueue, or so, for purposes of the
LED?
johannes
