An earlier commit, 'ath9k: remove dummy PCI "retry timeout" fix', removed
code that was documented to disable RETRY_TIMEOUT register (PCI reg
0x41) since it was claimed to be a no-op. However, it turns out that
there are some combinations of hosts and ath9k-supported cards for
which this is not a no-op (reg 0x41 has value 0x80, not 0) and this
code (or something similar) is needed. In such cases, the driver may
be next to unusable due to very frequent PCI FATAL interrupts from the
card.
Reverting the earlier commit, i.e., restoring the RETRY_TIMEOUT
disabling, seems to resolve the issue. Since the removal of this code
was not based on any known issue and was purely a cleanup change, the
safest option here is to just revert that commit. Should there be
desire to clean this up in the future, the change will need to be
tested with a more complete coverage of cards and host systems.
http://bugzilla.kernel.org/show_bug.cgi?id=13483
Cc: stable@kernel.org
Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch completely rewrites the rfkill core to address
the following deficiencies:
* all rfkill drivers need to implement polling where necessary
rather than having one central implementation
* updating the rfkill state cannot be done from arbitrary
contexts, forcing drivers to use schedule_work and requiring
lots of code
* rfkill drivers need to keep track of soft/hard blocked
internally -- the core should do this
* the rfkill API has many unexpected quirks, for example being
asymmetric wrt. alloc/free and register/unregister
* rfkill can call back into a driver from within a function the
driver called -- this is prone to deadlocks and generally
should be avoided
* rfkill-input pointlessly is a separate module
* drivers need to #ifdef rfkill functions (unless they want to
depend on or select RFKILL) -- rfkill should provide inlines
that do nothing if it isn't compiled in
* the rfkill structure is not opaque -- drivers need to initialise
it correctly (lots of sanity checking code required) -- instead
force drivers to pass the right variables to rfkill_alloc()
* the documentation is hard to read because it always assumes the
reader is completely clueless and contains way TOO MANY CAPS
* the rfkill code needlessly uses a lot of locks and atomic
operations in locked sections
* fix LED trigger to actually change the LED when the radio state
changes -- this wasn't done before
Tested-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> [thinkpad]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Jouni Malinen