We have seen the throughput dropped due to external noisy environment
and the radio is out of tune.  There are lot of plcp errors indicating
this condition. Eventually the station can get de-authenticated by the
Access Point.  By resetting and tuning the radio, the plcp errors are
reduced or eliminated and the throughput starts to rise.

To prevent unexpected behavior such as drop in throughput or deauthentication,
- The change provides the driver feature to monitor and tune the radio base on
the statistics notification from the uCode.
- It also allows the setting of the plcp error rate threshold via
the plcp_delta under debugfs interface.
Signed-off-by: Trieu 'Andrew' Nguyen <trieux.t.nguyen@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Add additional logic for internal scan routine to control how
frequent this function should be performed.

The intent of this function is to reset/re-tune the radio and bring the
RF/PHY back to normal state, it does not make sense calling it too
frequent,
if reset the radio can not bring it back to normal state, it indicate
there are other reason to cause the radio not operate correctly.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This patch allows A band to be scanned when driver is associated to AP.
Scan mechanism is that mac80211/cfg80211 requests driver to scan G band
first and then immediately to scan A band. Original code require
driver to wait for 2 seconds after any scan before another scan will be
performed. This caused driver to service G band scan request from
mac80211/cfg80211 but deny the A band scan request.
Signed-off-by: Henry Zhangh <hongx.c.zhang@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Adding "radio reset" function to help reset and stabilize the radio.

During normal operation, sometime for unknown reason, radio encounter
problem and can not recover by itself; the best way to
recover from it is to reset and re-tune the radio. Currently, there is
no RF reset command available, but since radio will get reset when
switching channel, use internal hw scan request to force radio
reset and get back to normal operation state.

The internal hw scan will only perform passive scan on the first
available channel (not the channel being used) in associated state. The
request should be ignored if already performing scan operation or STA is
not in associated state.

Also include an "internal_scan" debugfs file to help trigger the
internal scan from user mode.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Add support to configure missed beacon threshold, by default, if receive
"missed beacon" notification from uCode and has more than 5 consecutive
beacon missed, then perform sensitivity calibration; with this change,
allow user to adjust the missed beacon threshold from debugfs in case
more sensitivity calibration required for better performance in noisy
environment

The default value (=5) should be good enough for the normal condition,
but for very noisy environment, more sensitivity calibration could help
improve the throughput, so by setting the missed beacon threshold to
lower number, user might experience better performance result.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Pavel Roskin reported a crash in ieee80211_tx_h_select_key():

http://marc.info/?l=linux-wireless&m=126419655108528&w=2

This is a regression from patch "mac80211: move control.hw_key assignment".
Fix it as suggested by Johannes, adding an else statement to make sure
that tx->key is not accessed when it's null.

Compile-tested only.
Reported-by: Pavel Roskin <proski@gnu.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Kalle Valo <kalle.valo@iki.fi>
Tested-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ieee80211_tx_h_select_key might decide that a frame
need not be encrypted at all, in which case it will
clear tx->key. In that case it may crash if a key
was previously selected, e.g. as the default key.

This is also due to my patch
"mac80211: move control.hw_key assignment".
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This patch continues the effort which began with:
"[PATCH] p54pci: move tx cleanup into tasklet".

Thanks to these changes, p54pci's interrupt & tx
cleanup routines can be made lock-less.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

The loop that passes non-data frames to all relevant vifs inside the
__ieee80211_rx_handle_packet keeps a pointer to the previous sdata to
avoid having to make unnecessary copies of the frame it's handling.
This led to a bug that caused it to apply the ieee80211_rx_data state
to the wrong interface, thereby either missing the rx.sta pointer or
having it assigned where it shouldn't be.
This breaks (among other things) aggregation on some vifs, as action
frame exchages are dropped to the cooked monitor interface due to
rx->sta being NULL.
Fix this by restructuring the loop so that it prepares the rx data just
before making the skb copy and calling the rx handlers.

Cc: stable@kernel.org
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

As all bt packets are priority traffic during bt scan, wifi
will get disconnected when bt scan lasts for few seconds. Fix
this by allocating 10% of bt period time (4.5ms) to wifi fully.
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

The beacon sent gating doesn't seem to work with any combination
of flags.  Thus, buffered frames tend to stay buffered forever,
using up tx descriptors.

Instead, use the DBA gating and hold transmission of the buffered
frames until 80% of the beacon interval has elapsed using the ready
time.  This fixes the following error in AP mode:

   ath5k phy0: no further txbuf available, dropping packet

Add a comment to acknowledge that this isn't the best solution.
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Acked-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

When using the external sleep clock in AP mode, the
TSF increments too quickly, causing beacon interval
to be much lower than it is supposed to be, resulting
in lots of beacon-not-ready interrupts.

This fixes http://bugzilla.kernel.org/show_bug.cgi?id=14802.
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Acked-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ieee80211_hdrlen() should account account new HT Control field in 802.11
data frame header introduced by IEEE 802.11n standard.

According to 802.11n-2009 HT Control field is present in data frames
when both of following are met:

   1. It is QoS data frame.
   2. Order bit is set in Frame Control field.

The change might be totally compatible with legacy non-11n aware frames,
because 802.11-2007 standard states that "all QoS STAs set this subfield
to 0".
Signed-off-by: Andriy V. Tkachuk <andrit@ukr.net>
Acked-by : Benoit Papillault <benoit.papillault@free.fr>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

If a device has multiple MAC addresses, userspace will
need to know about that. Similarly, if it allows the
MAC addresses to vary by a bitmask.

If a driver exports multiple addresses, it is assumed
that it will be able to deal with that many different
addresses, which need not necessarily match the ones
programmed into the device; if a mask is set then the
device should deal addresses within that mask based
on an arbitrary "base address".

To test it all and show how it is used, add support
to hwsim even though it can't actually deal with
addresses different from the default.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

When a TKIP key is updated, we should pass the station
pointer instead of just the address, since drivers can
use that to store their own data. We also need to pass
the virtual interface pointer.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

"mac80211: move control.hw_key assignment" changed an if-else into two
separate if statments, but the if-else is needed to prevent
dereferencing a null info->control.hw_key.  This fixes avoids a lock-up
during association on my machine when using WEP.
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: John W. Linville <linville@tuxdriver.com>

Users wishing to tweak tx power want it to happen immediately,
try to respect that. This was tested by Lorenzo by measuring the
received signal strength from an AP with ath9k and the patch.

Changing the tx power on the AP produced these results:

1) iwconfig wlan0 txpower 20 ---> Rx power -37dbm
2) iwconfig wlan0 txpower 15 ---> Rx power -41dbm
3) iwconfig wlan0 txpower 10 ---> Rx power -45dbm
4) iwconfig wlan0 txpower 5 ---> Rx power -51dbm
5) iwconfig wlan0 txpower 0 ---> Rx power -37dbm

The result with 0 is an anomoly and would need to be
addressed through a separate patch.
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Tested-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

nl80211_associate() was rejecting (re)association attempts with EBUSY
in some cases where we are currently associated with an AP that uses
different channel from the destination AP. Fix this by passing the
current wdev to rdev_fixed_channel() in the same way that was already
done for join-IBSS and connect commands. This allows the fixedchan
check to skipped for the current wdev and allows the reassociation to
proceed.
Signed-off-by: Jouni Malinen <j@w1.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

With the v10 firmware running on 8688 HW, clearing WPA keys after setting the
WEP key prevents us from being able to associate with WEP APs.
Swapping the calling order for assoc_helper_wpa_keys() and
assoc_helper_wep_keys fixes that issue.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This patch moves the tx cleanup routines out of the critical
interrupt context and into the (previously known as rx) tasklet.

The main goal of this operation is to remove the extensive
usage of spin_lock_irqsaves in the generic p54common library.

The next step would be to modify p54usb to do the
rx processing inside a tasklet (just like usbnet).
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This patch adds error-paths to handle pci_dma_mapping errors.

Cc: <stable@kernel.org>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

First, both beacons and probe responses can be used for IBSS merge.
Next, sdata->u.ibss.bssid was always true (and thus IBSS merge was
disabled). We should use sdata->u.ibss.fixed_bssid instead.
Signed-off-by: Benoit Papillault <benoit.papillault@free.fr>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ieee82011_sta_find_ibss() and ieee80211_sta_merge_ibss() are always
called with a defined state. So it's useless to check it or set it in
those function.
Signed-off-by: Benoit Papillault <benoit.papillault@free.fr>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

The Tx DMA descriptor has two kinds of flags that select RTS/CTS usage.
The first one (global for the frame) selects whether RTS/CTS or
CTS-to-self should be used, the second one enables RTS/CTS or
CTS-to-self usage for an individual multi-rate-retry entry.
Previously the code preparing the descriptor only enabled the global
flag, if the first MRR series selected the local one.
Fix this by enabling the global flag if any of the MRR entries need it.
With this patch, rate control can properly select the use of RTS/CTS
for all MRR entries except the first one, which is the default behavior.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Future code will need to look up rdev and wdev
within atomic sections, but currently we need
to lock a mutex for such lookups. Change the
list handling for both to be RCU-safe so that
we can look them up in rcu sections instead in
the future.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>