When beacons get stuck in AP mode, the most likely cause is interference.
Such interference can often go on for a while, and too many consecutive
beacon misses can lead to connected clients getting dropped.

Since connected clients might not be subjected to the same interference
if that happens to be very local, the AP should try to deal with it as
good as it can. One way to do this is to trigger an NF calibration with
automatic baseband update right after the beacon miss. In my tests with
very strong interference, this allowed the AP to continue transmitting
beacons after only 2-3 misses, which allows a normal client to stay
connected.

With some of the newer - really sensitive - chips, the maximum noise
floor limit is very low, which can be problematic during very strong
interference. To avoid an endless loop of stuck beacons -> nfcal ->
periodic calibration -> stuck beacons, the beacon miss event also sets
a flag, which allows the calibration code to bypass the chip specific
maximum NF value. This flag is automatically cleared, as soon as the
first NF median goes back below the limits for all chains.

In my tests, this allowed an ath9k AP to survive very strong interference
(measured NF: -68, or sometimes even higher) without losing connectivity
to its clients. Even under these conditions, I was able to transmit
several mbits/s through the interface.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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

Stuck beacons are a useful indicator for debugging various PHY
issues such as calibration. Putting them on the same debug level
as the other beacon stuff makes it hard to spot them in huge amounts
of spam.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ieee80211_add_key() currently returns -ENOMEM in case of any error,
including a missing crypto algorithm.  Change ieee80211_key_alloc()
and ieee80211_aes_{key_setup_encrypt,cmac_key_setup}() to encode
errors with ERR_PTR() rather than returning NULL, and change
ieee80211_add_key() accordingly.

Compile-tested only.
Reported-by: Marcin Owsiany <porridge@debian.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Only the IBSS manager, ie. the station that sent
the IBSS beacon last, should be replying to probe
responses. This requires implementing the mac80211
tx_last_beacon callback, which we can do thanks to
the ucode beacon notification.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

iwl_set_hw_params() only used by _agn, make it static
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Log the information after reading the PCI_REVISION_ID
from pci config space,
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

iwl_hw_detect() only used by _agn, make it static
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Split some long lines to make checkpatch.pl happy. ;-)
Signed-off-by: Thomas Klute <thomas2.klute@uni-dortmund.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Signed-off-by: Thomas Klute <thomas2.klute@uni-dortmund.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Having both scan and work mutexes is not just
a bit too fine grained, it also creates issues
when there's code that needs both since they
then need to be acquired in the right order,
which can be hard to do.

Therefore, use just a single mutex for both.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

We do not need export iwl_bg.*scan.*() functions just for initialize
workqueue in other module. Making that functions static helps with
iwl-scan.c code review a bit.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Frames that failed PLCP error checks are most likely
microwave transmissions (well, maybe not ...) and
don't have a proper rate detected, so ignore it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Bring back the comment about FW v5 status codes from the pre-cfg80211
driver, and let through status codes that aren't remapped by the
firmware.
Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Make it a bit easier to debug scan results in the future.
Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This helps us debug channel changes better.
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

When running in client mode and associating to an AP, the channel
change is usually performed with the offchannel flag still set.
However after the assoc is complete, the following channel change event
is suppressed because the run time channel is already set to the operating channel.
Fix this by sending channel change notifications to the driver even if
only the offchannel flag changes.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This function was exiting early if the existing diversity settings
were unchanged.  Unfortunately, in some cases the antenna configuration
is not initialized at all.

https://bugzilla.kernel.org/show_bug.cgi?id=14751Signed-off-by: John W. Linville <linville@tuxdriver.com>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Cc: Gertjan van Wingerde <gwingerde@gmail.com>

...and unregistration to core shutdown.  Previously, the driver
remained registered even when the hardware was shutdown.  That
causes the driver to return -ENODEV if the b43 device is IFF_DOWN.
This change causes the driver to disappear in that case, allowing
/dev/hwrng to still function if another hwrng device is available.
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwmc3200wifi/rx.c: In function 'iwm_ntf_wifi_if_wrapper':
drivers/net/wireless/iwmc3200wifi/rx.c:1198: warning: comparison is always true due to limited range of data type

This is, of course, because the value of WIFI_IF_NTFY_MAX is 0xff and
hdr->oid is a u8.  This is obviously an attempt to verify the range on
an input value, but since it has no effect it can simply be removed.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Acked-by: Samuel Ortiz <samuel.ortiz@intel.com>

drivers/net/wireless/ipw2x00/ipw2100.c: In function 'ipw2100_tx_send_commands':
drivers/net/wireless/ipw2x00/ipw2100.c:3063: warning: cast to pointer from integer of different size

This changes the cast and the conversion to match other usage of the
same value in calls to IPW_DEBUG_TX.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Some iwlwifi devices inexplicably disconnect themselves from the PCI-E
bus causing the predictable failures.  This seems to disappear if ASPM
is disabled.
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This provides a little more flexibility for human users, and it allows
us to use isalpha rather than the custom is_alpha_upper.
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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

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

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

This patch implement basic infrastructure to support use of NAPI by
mac80211-based hardware drivers.

Because mac80211 devices can support multiple netdevs, a dummy netdev
is used for interfacing with the NAPI code in the core of the network
stack.  That structure is hidden from the hardware drivers, but the
actual napi_struct is exposed in the ieee80211_hw structure so that the
poll routines in drivers can retrieve that structure.  Hardware drivers
can also specify their own weight value for NAPI polling.
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This makes the information available through ethtool...
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This makes the information available through ethtool...
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>

This makes the information available through ethtool...
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This makes the information available through ethtool...
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This makes the information available through ethtool...
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Atheros PCIe wireless cards handled by ath5k do require L0s disabled.
For distributions shipping with CONFIG_PCIEASPM (this will be enabled
by default in the future in 2.6.36) this will also mean both L1 and L0s
will be disabled when a pre 1.1 PCIe device is detected. We do know L1
works correctly even for all ath5k pre 1.1 PCIe devices though but cannot
currently undue the effect of a blacklist, for details you can read
pcie_aspm_sanity_check() and see how it adjusts the device link
capability.

It may be possible in the future to implement some PCI API to allow
drivers to override blacklists for pre 1.1 PCIe but for now it is
best to accept that both L0s and L1 will be disabled completely for
distributions shipping with CONFIG_PCIEASPM rather than having this
issue present. Motivation for adding this new API will be to help
with power consumption for some of these devices.

Example of issues you'd see:

  - On the Acer Aspire One (AOA150, Atheros Communications Inc. AR5001
    Wireless Network Adapter [168c:001c] (rev 01)) doesn't work well
    with ASPM enabled, the card will eventually stall on heavy traffic
    with often 'unsupported jumbo' warnings appearing. Disabling
    ASPM L0s in ath5k fixes these problems.

  - On the same card you would see a storm of RXORN interrupts
    even though medium is idle.

Credit for root causing and fixing the bug goes to Jussi Kivilinna.

Cc: David Quan <David.Quan@atheros.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Tim Gardner <tim.gardner@canonical.com>
Cc: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Cc: stable@kernel.org
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This patch handles the firmware loading properly
for device ID 7015.
Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Use appropriate command (CMD_TRIGGER_SCAN_TO) instead of scan command
(CMD_SCAN) to configure trigger scan timeout.

This was broken in commit 3a98c30f.

This fix address the bug reported here:

https://bugzilla.kernel.org/show_bug.cgi?id=16554

Cc: stable@kernel.org
Signed-off-by: Yuri Ershov <ext-yuri.ershov@nokia.com>
Signed-off-by: Yuri Kululin <ext-yuri.kululin@nokia.com>
Acked-by: Kalle Valo <kvalo@adurom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Some APs advertise that they may be HT40 capable in the capabilites
but the current operating channel configuration may be only HT20.
This causes disconnection as ath9k_htc sets WLAN_RC_40_FLAG despite
the AP operating in HT20 mode.
Hence set this flag only if the current channel configuration
is HT40 enabled.

Cc: stable@kernel.org
Signed-off-by: Vivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

This should fix the oops which occurs during the packet injection
on monitor interface.

EIP is at ath9k_htc_tx_start+0x69/0x220 [ath9k_htc]
 [<f84dc8ea>] ? invoke_tx_handlers+0xa5a/0xee0 [mac80211]
 [<f82c84f4>] ? ath9k_htc_tx+0x44/0xe0 [ath9k_htc]
 [<f84db7b8>] ? __ieee80211_tx+0xf8/0x190 [mac80211]
 [<f84dce0d>] ? ieee80211_tx+0x9d/0x1a0 [mac80211]
 [<f84dcfac>] ? ieee80211_xmit+0x9c/0x1c0 [mac80211]
 [<f84dd1b5>] ? ieee80211_monitor_start_xmit+0x85/0xb0 [mac80211]
 [<c04c30cd>] ? dev_hard_start_xmit+0x1ad/0x210
 [<c04b97c2>] ? __alloc_skb+0x52/0x130
 [<c04d7cd5>] ? sch_direct_xmit+0x105/0x170
 [<c04c5e9f>] ? dev_queue_xmit+0x37f/0x4b0
 [<c0567e1e>] ? packet_snd+0x21e/0x250
 [<c05684a2>] ? packet_sendmsg+0x32/0x40
 [<c04b4c63>] ? sock_aio_write+0x113/0x130
 [<c0207934>] ? do_sync_write+0xc4/0x100
 [<c0167740>] ? autoremove_wake_function+0x0/0x50
 [<c02f4414>] ? security_file_permission+0x14/0x20
 [<c0207ad4>] ? rw_verify_area+0x64/0xe0
 [<c01e6458>] ? handle_mm_fault+0x338/0x390
 [<c0207cd5>] ? vfs_write+0x185/0x1a0
 [<c058db20>] ? do_page_fault+0x160/0x3a0
 [<c0208512>] ? sys_write+0x42/0x70
 [<c01033ec>] ? syscall_call+0x7/0xb
Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>

It is necessary to call pm_qos_add_request prior to calling
pm_qos_update_request.  It was revealed that ipw2100 has been
doing this wrong since "pm_qos: Get rid of the allocation in
pm_qos_add_request()" (commit 82f68251)
added a WARN that results in the following backtrace:

WARNING: at kernel/pm_qos_params.c:264 pm_qos_update_request+0x5e/0x70()
pm_qos_update_request() called for unknown object
Call Trace:
[<c1024088>] ? warn_slowpath_common+0x78/0xb0
[<c1041c9e>] ? pm_qos_update_request+0x5e/0x70
[<c1041c9e>] ? pm_qos_update_request+0x5e/0x70
[<c1024153>] ? warn_slowpath_fmt+0x33/0x40
[<c1041c9e>] ? pm_qos_update_request+0x5e/0x70
[<f89fe15f>] ? ipw2100_up+0x3f/0xf10 [ipw2100]
[<c11961c9>] ? vsnprintf+0xc9/0x530
[<f89ff36c>] ? ipw2100_net_init+0x2c/0x1c0 [ipw2100]
[<c12f542d>] ? register_netdevice+0x7d/0x3c0
[<f89f9b00>] ? ipw2100_irq_tasklet+0x910/0x9a0 [ipw2100]
[<c12f579f>] ? register_netdev+0x2f/0x40
[<f89fd471>] ? ipw2100_pci_init_one+0xd21/0x1060 [ipw2100]
[<c11a5ebb>] ? local_pci_probe+0xb/0x10
[<c11a6d49>] ? pci_device_probe+0x69/0x90
[<c1224704>] ? driver_probe_device+0x74/0x180
[<c10dd15a>] ? sysfs_create_dir+0x6a/0xb0
[<c1224889>] ? __driver_attach+0x79/0x80
[<c1224810>] ? __driver_attach+0x0/0x80
[<c1223fa2>] ? bus_for_each_dev+0x52/0x80
[<c1224586>] ? driver_attach+0x16/0x20
[<c1224810>] ? __driver_attach+0x0/0x80
[<c122395f>] ? bus_add_driver+0x17f/0x250
[<c11a5ec0>] ? pci_device_shutdown+0x0/0x20
[<c11a6c80>] ? pci_device_remove+0x0/0x40
[<c1224b13>] ? driver_register+0x63/0x120
[<c11a6f96>] ? __pci_register_driver+0x36/0xa0
[<f84f9048>] ? ipw2100_init+0x48/0x67 [ipw2100]
[<c1001122>] ? do_one_initcall+0x32/0x170
[<c1087078>] ? __vunmap+0xb8/0xf0
[<f84f9000>] ? ipw2100_init+0x0/0x67 [ipw2100]
[<c10510c1>] ? sys_init_module+0x161/0x1000
[<c108f847>] ? sys_close+0x67/0xe0
[<c13647c1>] ? syscall_call+0x7/0xb

This patch moves pm_qos_add_request prior to pci_register_driver in
ipw2100 in order to avoid this problem.
Reported-by: Christoph Fritz <chf.fritz@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>