rfkill: protect suspended rfkill controllers

Guard rfkill controllers attached to a rfkill class against state changes
after class suspend has been issued.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Henrique de Moraes Holschuh 2008-08-02 14:56:25 -03:00 committed by John W. Linville
parent aaa1553512
commit e10e0dfe3b
2 changed files with 15 additions and 4 deletions

View file

@ -363,6 +363,11 @@ This rule exists because users of the rfkill subsystem expect to get (and set,
when possible) the overall transmitter rfkill state, not of a particular rfkill
line.
5. During suspend, the rfkill class will attempt to soft-block the radio
through a call to rfkill->toggle_radio, and will try to restore its previous
state during resume. After a rfkill class is suspended, it will *not* call
rfkill->toggle_radio until it is resumed.
Example of a WLAN wireless driver connected to the rfkill subsystem:
--------------------------------------------------------------------

View file

@ -150,6 +150,8 @@ static void update_rfkill_state(struct rfkill *rfkill)
* calls and handling all the red tape such as issuing notifications
* if the call is successful.
*
* Suspended devices are not touched at all, and -EAGAIN is returned.
*
* Note that the @force parameter cannot override a (possibly cached)
* state of RFKILL_STATE_HARD_BLOCKED. Any device making use of
* RFKILL_STATE_HARD_BLOCKED implements either get_state() or
@ -168,6 +170,9 @@ static int rfkill_toggle_radio(struct rfkill *rfkill,
int retval = 0;
enum rfkill_state oldstate, newstate;
if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
return -EBUSY;
oldstate = rfkill->state;
if (rfkill->get_state && !force &&
@ -214,7 +219,7 @@ static int rfkill_toggle_radio(struct rfkill *rfkill,
*
* This function toggles the state of all switches of given type,
* unless a specific switch is claimed by userspace (in which case,
* that switch is left alone).
* that switch is left alone) or suspended.
*/
void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state)
{
@ -239,8 +244,8 @@ EXPORT_SYMBOL(rfkill_switch_all);
/**
* rfkill_epo - emergency power off all transmitters
*
* This kicks all rfkill devices to RFKILL_STATE_SOFT_BLOCKED, ignoring
* everything in its path but rfkill_mutex and rfkill->mutex.
* This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
* ignoring everything in its path but rfkill_mutex and rfkill->mutex.
*/
void rfkill_epo(void)
{
@ -458,13 +463,14 @@ static int rfkill_resume(struct device *dev)
if (dev->power.power_state.event != PM_EVENT_ON) {
mutex_lock(&rfkill->mutex);
dev->power.power_state.event = PM_EVENT_ON;
/* restore radio state AND notify everybody */
rfkill_toggle_radio(rfkill, rfkill->state, 1);
mutex_unlock(&rfkill->mutex);
}
dev->power.power_state = PMSG_ON;
return 0;
}
#else