| commit | 559850bb1cb43fe20be82e068ef232df18e4ea21 | |
| author | Stanislaw Gruszka <sgruszka@redhat.com> | |
| Thu, 13 Aug 2009 12:29:08 +0000 (13 14:29 +0200) | ||
| committer | Greg Kroah-Hartman <gregkh@suse.de> | |
| Wed, 9 Sep 2009 03:33:38 +0000 (8 20:33 -0700) | ||
| tree | 582dfeb2aa9893f32e201a4f3fdd2e153bb36018 | treesnapshot (tar.gz zip) |
| parent | 378392b260dbe265401948d5d5b77fe6d537501c | commitdiff |
iwl3945: fix rfkill switch
(Not needed upstream, due to the major rewrite in 2.6.31)
Due to rfkill and iwlwifi mishmash of SW / HW killswitch representation,
we have race conditions which make unable turn wifi radio on, after enable
and disable again killswitch. I can observe this problem on my laptop
with iwl3945 device.
In rfkill core HW switch and SW switch are separate 'states'. Device can
be only in one of 3 states: RFKILL_STATE_SOFT_BLOCKED, RFKILL_STATE_UNBLOCKED,
RFKILL_STATE_HARD_BLOCKED. Whereas in iwlwifi driver we have separate bits
STATUS_RF_KILL_HW and STATUS_RF_KILL_SW for HW and SW switches - radio can be
turned on, only if both bits are cleared.
In this particular race conditions, radio can not be turned on if in driver
STATUS_RF_KILL_SW bit is set, and rfkill core is in state
RFKILL_STATE_HARD_BLOCKED, because rfkill core is unable to call
rfkill->toggle_radio(). This situation can be entered in case:
- killswitch is turned on
- rfkill core 'see' button change first and move to RFKILL_STATE_SOFT_BLOCKED
also call ->toggle_radio() and STATE_RF_KILL_SW in driver is set
- iwl3945 get info about button from hardware to set STATUS_RF_KILL_HW bit and
force rfkill to move to RFKILL_STATE_HARD_BLOCKED
- killsiwtch is turend off
- driver clear STATUS_RF_KILL_HW
- rfkill core is unable to clear STATUS_RF_KILL_SW in driver
Additionally call to rfkill_epo() when STATUS_RF_KILL_HW in driver is set
cause move to the same situation.
In 2.6.31 this problem is fixed due to _total_ rewrite of rfkill subsystem.
This is a quite small fix for 2.6.30.x in iwlwifi driver. We are changing
internal rfkill state to always have below relations true:
STATUS_RF_KILL_HW=1 STATUS_RF_KILL_SW=1 <-> RFKILL_STATUS_SOFT_BLOCKED
STATUS_RF_KILL_HW=0 STATUS_RF_KILL_SW=1 <-> RFKILL_STATUS_SOFT_BLOCKED
STATUS_RF_KILL_HW=1 STATUS_RF_KILL_SW=0 <-> RFKILL_STATUS_HARD_BLOCKED
STATUS_RF_KILL_HW=0 STATUS_RF_KILL_SW=0 <-> RFKILL_STATUS_UNBLOCKED
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Reinette Chatre <reinette.chatre@intel.com>
Acked-by: John W. Linville <linville@tuxdriver.com>
(Not needed upstream, due to the major rewrite in 2.6.31)
Due to rfkill and iwlwifi mishmash of SW / HW killswitch representation,
we have race conditions which make unable turn wifi radio on, after enable
and disable again killswitch. I can observe this problem on my laptop
with iwl3945 device.
In rfkill core HW switch and SW switch are separate 'states'. Device can
be only in one of 3 states: RFKILL_STATE_SOFT_BLOCKED, RFKILL_STATE_UNBLOCKED,
RFKILL_STATE_HARD_BLOCKED. Whereas in iwlwifi driver we have separate bits
STATUS_RF_KILL_HW and STATUS_RF_KILL_SW for HW and SW switches - radio can be
turned on, only if both bits are cleared.
In this particular race conditions, radio can not be turned on if in driver
STATUS_RF_KILL_SW bit is set, and rfkill core is in state
RFKILL_STATE_HARD_BLOCKED, because rfkill core is unable to call
rfkill->toggle_radio(). This situation can be entered in case:
- killswitch is turned on
- rfkill core 'see' button change first and move to RFKILL_STATE_SOFT_BLOCKED
also call ->toggle_radio() and STATE_RF_KILL_SW in driver is set
- iwl3945 get info about button from hardware to set STATUS_RF_KILL_HW bit and
force rfkill to move to RFKILL_STATE_HARD_BLOCKED
- killsiwtch is turend off
- driver clear STATUS_RF_KILL_HW
- rfkill core is unable to clear STATUS_RF_KILL_SW in driver
Additionally call to rfkill_epo() when STATUS_RF_KILL_HW in driver is set
cause move to the same situation.
In 2.6.31 this problem is fixed due to _total_ rewrite of rfkill subsystem.
This is a quite small fix for 2.6.30.x in iwlwifi driver. We are changing
internal rfkill state to always have below relations true:
STATUS_RF_KILL_HW=1 STATUS_RF_KILL_SW=1 <-> RFKILL_STATUS_SOFT_BLOCKED
STATUS_RF_KILL_HW=0 STATUS_RF_KILL_SW=1 <-> RFKILL_STATUS_SOFT_BLOCKED
STATUS_RF_KILL_HW=1 STATUS_RF_KILL_SW=0 <-> RFKILL_STATUS_HARD_BLOCKED
STATUS_RF_KILL_HW=0 STATUS_RF_KILL_SW=0 <-> RFKILL_STATUS_UNBLOCKED
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Reinette Chatre <reinette.chatre@intel.com>
Acked-by: John W. Linville <linville@tuxdriver.com>
| drivers/net/wireless/iwlwifi/iwl-rfkill.c | diffblobblamehistory |