Re: [PATCH 1/1] toshiba_acpi: Add support for bluetooth togglingthrough rfkill (v2)

From: Philip Langdale
Date: Thu Aug 07 2008 - 01:05:31 EST


Henrique de Moraes Holschuh wrote:

Well, the textbook way to connect that to rfkill is something like this,
please check if it makes sense:

Export (1) as a input device (you have events to hook to when it changes
state) or polled input device (you don't have said events). Do NOT register
(1) with a struct rfkill at all. It is purely an input device.

DO NOT expose (2) as an input device at all. Instead, register it to a
rfkill struct, of type bluetooth.

On the event handler for (1), you issue the EV_SW SW_RFKILL_ALL input event.
Since you *do* know events from (1) are likely to also have messed with the
state of (2), you also check (2)'s state at this time and update it through
rfkill_force_state().

Due to the interaction of 1 and 2, you need to implement and deal with
RFKILL_STATE_HARD_BLOCKED. Since you do know the firmware will be
hard-blocking (2) when (1) is active, you return RFKILL_STATE_HARD_BLOCKED
for (2)'s state every time (1) is active. Otherwise, you return
RFKILL_STATE_SOFT_BLOCKED when (2) is blocked, and RFKILL_STATE_UNBLOCKED
otherwise.

This will cause the state of (2) to go to either RFKILL_STATE_HARD_BLOCKED
or RFKILL_STATE_SOFT_BLOCKED when (1) changes state.

[Note: the above does assume (1) blocks (2) in some way you cannot override,
and that trying to unblock (2) while (1) is blocking it is futile].

rfkill-input (now) or userspace (someday) will take care of kicking the
radio to RFKILL_STATE_UNBLOCKED when (1) issues an event that signals that
radios don't have to remain blocked. Maybe this is why you see the WLAN
going on when you deactivate the radio kill switch?

And rfkill-input will soon be enhanced to let the user configure it to do
something different if he wants. Your driver doesn't (and shouldn't)
hardcode policy about it.

Hmm. So, I've updated the diff to do this, but rfkill-input is not kicking
the bluetooth device back on after I release the kill switch. it just returns
to SOFT_UNBLOCKED and stays there.

--phil
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