From e10e0dfe3ba358cfb442cc3bf0d3f2068785bf5c Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Sat, 2 Aug 2008 14:56:25 -0300 Subject: [PATCH] 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 Acked-by: Ivo van Doorn Signed-off-by: John W. Linville --- Documentation/rfkill.txt | 5 +++++ net/rfkill/rfkill.c | 14 ++++++++++---- 2 files changed, 15 insertions(+), 4 deletions(-) diff --git a/Documentation/rfkill.txt b/Documentation/rfkill.txt index 28b6ec8..6fcb306 100644 --- a/Documentation/rfkill.txt +++ b/Documentation/rfkill.txt @@ -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: -------------------------------------------------------------------- diff --git a/net/rfkill/rfkill.c b/net/rfkill/rfkill.c index d2d4565..35a9994 100644 --- a/net/rfkill/rfkill.c +++ b/net/rfkill/rfkill.c @@ -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 -- 2.7.4