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path: root/drivers/net/wireless/ath/ath9k/beacon.c
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* ath9k: implement .tx_last_beacon()Felix Fietkau2011-05-19
| | | | | Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: fix ad-hoc nexttbtt calculationFelix Fietkau2011-05-19
| | | | | | | | | | rounding up the delta between last-beacon-tsf and tsf to intval is wrong and can lead to misconfigured timers which breaks beacon transmission. Fix this by adding intval and subtracting the offset of the tsf within the current slot. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Drag the driver to the year 2011Sujith Manoharan2011-05-19
| | | | | | | The Times They Are a-Changin'. Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: fix ad-hoc mode beacon selectionFelix Fietkau2011-05-19
| | | | | | | | | | | | | In ad-hoc mode, beacon timers are configured differently compared to AP mode, and (depending on the scenario) can vary enough to make the beacon tasklet not detect slot 0 based on the TSF. Since staggered beacons are not (and cannot be) used in ad-hoc mode, it makes more sense to just hardcode slot 0 here, avoiding unnecessary TSF reads and calculations. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Reported-by: Rajkumar Manoharan <rmanoharan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: avoid enabling interrupts while processing rxRajkumar Manoharan2011-05-10
| | | | | | | | | | | | The assumsion is that while processing ath9k tasklet, interrupts were already disabled and it will be enabled at the completion of ath9k tasklet. But whenever TSFOOR is raised, the driver configures the beacon timers after having received a beacon frame from the AP which inturn enables the interrupts. Cc: stable@kernel.org Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: set beacon related ps flags on bss_info changeRajkumar Manoharan2011-04-26
| | | | | | | | | | Requesting beacon sync up to configure beacon timers properly in hw, has be done after doing beacon config with default values. Setting the flags in beacon config is causing the device to not enter into network sleep on idle state. Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Fix beacon generation on foreign channelRajkumar Manoharan2011-04-19
| | | | | | | | | | | | | | | | | | | While leaving the oper channel, beacon generation is stopped by mac80211 and beacon slots are marked as inactive. During the scan, ath9k configures beacon timers based on IEEE80211_CONF_OFFCHANNEL which inturn generates beacon alert even though bslot is inactive. ath9k fails to disable beacon alert while moving to offchannel if none of the beacon slot is active. This is causing beacon transmission on foreign channel. This patch enables swba based on active bslots. This issue was reported with two vifs (AP+STA) and triggered scan in STA vif in unassociated state. Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Fix improper beacon slot selection in IBSSRajkumar Manoharan2011-04-14
| | | | | | | | | | Request a re-configuration of Beacon related timers on the receipt of the first Beacon frame has to be set only for station mode. Setting beacon sync for IBSS is causing wrong beacon slot selection on beacon generation. Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Fix kernel panic on module unloadRajkumar Manoharan2011-04-12
| | | | | | | | | The commit "ath9k: configure beacons based on hw opmode" introduced a regression which leads to kernel panic. Failed to stop ani timer during the driver unload while any of the beaconing vif is running. Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: configure beacons based on hw opmodeRajkumar Manoharan2011-04-07
| | | | | | | | | | | | | | | | Current ath9k code does not handle beacon timers on opmode specific. One such example is that a STA beacon config overwrites already configured AP vif's beacon timers during scan. On multi station vif case, configure beacon timers beased on primary vif selected. This also helps while moving back to single STA vif from multi STA vifs, where the power save is enabled and hw has to be reconfigured with proper beacon and bssid/aid. Otherwise connection poll will be triggered so frequently due to beacon loss. Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Cleanup ath_vif structRajkumar Manoharan2011-04-07
| | | | | | | | Remove unused bssid from ath_vif and set av_bslot on beacon alloc/return. Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: use the hw opmode to select the beacon timer modeFelix Fietkau2011-04-07
| | | | | | | | | Since the beacon timers are global, the individual vif type should not be used to determine the beacon timer configuration mode, use the global opmode instead. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: fix beacon slot processing in ad-hoc modeFelix Fietkau2011-04-07
| | | | | | | | | | | | | The recent cleanups in the beacon code fixed SWBA backoff calculation, however it did not remove a line of code that worked around the issues from the earlier version of the code. After the cleanup, the initial TSF based slot calculation now always returns 0 instead of ATH_BCBUF-1, so the previous hack that reversed the slot order needs to be removed, as ad-hoc mode does not use staggered beacons. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: fix stuck beacon detectionFelix Fietkau2011-03-30
| | | | | | | | | | | | | | | Stuck beacon detection is supposed to trigger when 9 consecutive beacons could not be sent by the hardware. When the driver runs only one active AP mode interface, it still configures the hardware beacon timer for 4 (ATH_BCBUF) beacon slots slots, which causes stuck beacon detection to be reset if ath9k_hw_stoptxdma clears the stuck frames between SWBA intervals. Fix this by not resetting the missed beacon count for empty slots and multiplying the threshold not by the maximum number of beacon slots but by the configured number of beacon interfaces. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: trigger nfcal only after multiple missed beacons in AP modeFelix Fietkau2011-03-30
| | | | | | | | | Single missed (i.e. not transmitted) beacons in AP mode are not very rare and not necessarily an indicator of strong interference, so only trigger noise floor recalibration when multiple consecutive beacons could not be transmitted. Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: fix beacon timer handling issuesFelix Fietkau2011-03-30
| | | | | | | | | | | | | | | | AP mode beacon timers in ath9k are configured in milliseconds, which breaks when increasing ATH_BCBUF to 8 instead of 4 (due to rounding errors). Since the hardware timers are actually configured in microseconds, it's better to let the driver use that unit directly. To be able to do that, the beacon interval parameter abuse for passing certain flags needs to be removed. This is easy to do, because those flags are completely unnecessary anyway. ATH9K_BEACON_ENA is ignored, ATH9K_BEACON_RESET_TSF can be replaced with calling ath9k_hw_reset_tsf from the driver directly. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: improve reliability of beacon transmission and stuck beacon handlingFelix Fietkau2011-03-14
| | | | | | | | | | | | | | | | | | ath9k calls ath9k_hw_stoptxdma every time it sends a beacon, however there is not much point in doing that if the previous beacon and mcast traffic went out properly. On AR9380, calling that function too often can result in an increase of stuck beacons due to differences in the handling of the queue enable/disable functionality. With this patch, the queue will only be explicitly stopped if the previous data frames were not sent successfully. With the beacon code being the only remaining user of ath9k_hw_stoptxdma, this function can be simplified in order to remove the now pointless attempts at waiting for transmission completion, which would never happen at this point due to the different method of tx scheduling of the beacon queue. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: disable beaconing before stopping beacon queueRajkumar Manoharan2011-02-14
| | | | | | | | | | Beaconing should be disabled before stopping beacon queue. Not doing so could queue up beacons in hw that causes failure to stop Tx DMA, due to pending frames in hw and also unnecessary beacon tasklet schedule. Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Remove redundant beacon_intervalSteve Brown2011-02-09
| | | | | | | | | | The variable appears in both ath_softc and ath_beacon_config. The struct ath_beacon_config is embedded in ath_softc. The redundant variable was added by commit id 57c4d7b4c4986037be51476b8e3025d5ba18d8b8. Signed-off-by: Steve Brown <sbrown@cortland.com> Reviewed-by: Mohammed Shafi <shafi.ath9k@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Update comments for not parsing DTIM periodMohammed Shafi Shajakhan2011-02-07
| | | | | | | Add few comments for not parsing DTIM period from mac80211 Signed-off-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: fold struct ath_wiphy into struct ath_softcFelix Fietkau2011-01-28
| | | | | Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: remove support for virtual wiphysFelix Fietkau2011-01-28
| | | | | Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: remove a bogus error messageFelix Fietkau2011-01-21
| | | | | | | | | When beacons are being added or removed for an interface, ieee80211_beacon_get will sometimes not return a beacon. This is normal and should not result in useless logspam. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Fix up hardware mode and beacons with multiple vifs.Ben Greear2011-01-19
| | | | | | | | | | | | | | | | | | When using a mixture of AP and Station interfaces, the hardware mode was using the type of the last VIF registered. Instead, we should keep track of the number of different types of vifs and set the mode accordingly. In addtion, use the vif type instead of hardware opmode when dealing with beacons. Attempt to move some of the common setup code into smaller methods so we can re-use it when changing vif mode as well as adding/deleting vifs. Signed-off-by: Ben Greear <greearb@candelatech.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Few clean ups in beacon config parametersMohammed Shafi Shajakhan2011-01-04
| | | | | | | Some minor clean ups in assigning values to beacon config parameters Signed-off-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath: Convert ath_print to ath_dbgJoe Perches2010-12-07
| | | | | | | | | | | Remove ath/debug.h and the includes of these files. Coalesce long formats. Correct a few misspellings and missing "\n"s from these logging messages. Remove unnecessary trailing space before a newline. Remove ARRAY_SIZE casts, use printf type %zu Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath: Convert ath_print(.., ATH_DBG_FATAL to ath_errJoe Perches2010-12-07
| | | | | | | | So these errors are always emitted at KERN_ERR level. Remove ARRAY_SIZE casts, use printf type %zu Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Add support for Adaptive Power ManagementMohammed Shafi Shajakhan2010-11-30
| | | | | | | | | | | | | | | | | This feature is to mitigate the problem of certain 3 stream chips that exceed the PCIe power requirements.An EEPROM flag controls which chips have APM enabled which is basically read from miscellaneous configuration element of the EEPROM header. This workaround will reduce power consumption by using 2 Tx chains for Single and Double stream rates (5 GHz only).All self generated frames (regardless of rate) are sent on 2 chains when this feature is enabled(Chip Limitation). Cc: Paul Shaw <paul.shaw@atheros.com> Signed-off-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com> Tested-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: clean up code duplication around ath_tx_startFelix Fietkau2010-11-17
| | | | | | | | Merge initial processing for the CAB queue and regular tx. Also move ath_tx_cabq() to beacon.c and make it static. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: rework tx queue selection and fix queue stopping/wakingFelix Fietkau2010-11-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current ath9k tx queue handling code showed a few issues that could lead to locking issues, tx stalls due to stopped queues, and maybe even DMA issues. The main source of these issues is that in some places the queue is selected via skb queue mapping in places where this mapping may no longer be valid. One such place is when data frames are transmitted via the CAB queue (for powersave buffered frames). This is made even worse by a lookup WMM AC values from the assigned tx queue (which is undefined for the CAB queue). This messed up the pending frame counting, which in turn caused issues with queues getting stopped, but not woken again. To fix these issues, this patch removes an unnecessary abstraction separating a driver internal queue number from the skb queue number (not to be confused with the hardware queue number). It seems that this abstraction may have been necessary because of tx queue preinitialization from the initvals. This patch avoids breakage here by pushing the software <-> hardware queue mapping to the function that assigns the tx queues and redefining the WMM AC definitions to match the numbers used by mac80211 (also affects ath9k_htc). To ensure consistency wrt. pending frame count tracking, these counters are moved to the ath_txq struct, updated with the txq lock held, but only where the tx queue selected by the skb queue map actually matches the tx queue used by the driver for the frame. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Reported-by: Björn Smedman <bjorn.smedman@venatech.se> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k_hw: optimize interrupt mask changesFelix Fietkau2010-11-09
| | | | | | | | | | | | | | | OProfile showed that ath9k was spending way too much time in ath9k_hw_set_interrupts. Since most of the interrupt mask changes only need to globally enable/disable interrupts, it makes sense to split this part into separate functions, replacing all calls to ath9k_hw_set_interrupts(ah, 0) with ath9k_hw_disable_interrupts(ah). ath9k_hw_set_interrupts(ah, ah->imask) only gets changed to ath9k_hw_enable_interrupts(ah), whenever ah->imask was not changed since the point where interrupts were disabled. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: resume aggregation immediately after a hardware resetFelix Fietkau2010-10-25
| | | | | | | | | | | | Since aggregation is usually triggered by tx completion, a hardware reset (because of beacon stuck, tx hang or baseband hang) can significantly delay the transmission of the next AMPDU (until the next tx completion event). Fix this by rescheduling aggregation after such a reset. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Cc: stable@kernel.org Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Null out references to stale pointers.Ben Greear2010-10-15
| | | | | | | | | This doesn't fix any problem that I'm aware of, but should make it harder to add use-after-free type bugs in the future. Signed-off-by: Ben Greear <greearb@candelatech.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Remove bf_dmacontext.Ben Greear2010-10-15
| | | | | | | | | The bf_dmacontext seems to be totally useless and duplicated by bf_buf_addr. Remove it entirely, use bf_buf_addr in its place. Signed-off-by: Ben Greear <greearb@candelatech.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: use AP beacon miss as a trigger for fast recalibrationFelix Fietkau2010-08-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* ath9k: add a separate debug level for stuck beaconsFelix Fietkau2010-08-16
| | | | | | | | | | 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>
* ath9k: remove duplicate WMM AC definitionsFelix Fietkau2010-06-14
| | | | | Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: remove VEOL support for ad-hocFelix Fietkau2010-05-25
| | | | | | | | | | | With VEOL, Beacon transmission in ad-hoc does not currently work. I believe for larger ad-hoc networks, VEOL is too unreliable, as it can get beacon transmissions stuck during synchronization. Use SWBA based beacon trasmission similar to AP mode instead. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Acked-by: Benoit Papillault <benoit.papillault@free.fr> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: change beacon allocation to prefer the first beacon slotFelix Fietkau2010-05-25
| | | | | | | This fixes IBSS beacon transmissions without VEOL enabled Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k_hw: Define abstraction for tx desc accessVasanthakumar Thiagarajan2010-04-16
| | | | | Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k_hw: Move code which populates ds_data to ath9k_hwVasanthakumar Thiagarajan2010-04-16
| | | | | Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: move imask from sc to ahPavel Roskin2010-04-06
| | | | | | | | Add ah variable in the functions that didn't have it and used sc->imask. Replace sc->sc_ah with ah in those functions. Signed-off-by: Pavel Roskin <proski@gnu.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: fix beacon timer restart after a card resetFelix Fietkau2010-02-19
| | | | | | | | | | | | | | | | | | | | In AP mode, ath_beacon_config_ap only restarts the timer if a TSF restart is requested. Apparently this was added, because this function unconditionally sets the flag for TSF reset. The problem with this is, that ath9k_hw_reset() clobbers the timer registers (specified in the initvals), thus effectively disabling the SWBA interrupt whenever a card reset without TSF reset is issued (happens in a few places in the code). This patch fixes ath_beacon_config_ap to only issue the TSF reset flag when necessary, but reinitialize the timer unconditionally. Tests show, that this is enough to keep the SWBA interrupt going after a call to ath_reset() Signed-off-by: Felix Fietkau <nbd@openwrt.org> Cc: stable@kernel.org Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Use the Beacon TX rate from mac80211Jouni Malinen2010-02-16
| | | | | | | | Instead of hardcoding the lowest rate for Beacon frames, use the rate index specified in the mac80211 TX info in AP mode. Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: configure the beacon only if the STA is associatedSenthil Balasubramanian2010-02-08
| | | | | | | beacons configuration SHOULD be done only if the STA is associated. Signed-off-by: Senthil Balasubramanian <senthilkumar@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: cleanup slot time and ack/cts timeout handlingFelix Fietkau2010-01-15
| | | | | | | | | | | | | Previously ath9k left the initialization of slot timing and ACK/CTS timeout to the mode specific initvals. This does not handle short vs long slot in 2.4 GHz and uses a rather strange value for the 2.4 GHz ACK timeout (64 usec). This patch uses the proper ath9k_hw functions for setting slot time and timeouts and also implements the switch between short and long slot time in 2.4 GHz Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: Ensure a fair beacon distribution in IBSS mode.Vivek Natarajan2009-11-28
| | | | | | | | | | | Update the beacon queue parameters with best effort queue parameters for IBSS mode. This reduces the number of beacons generated by ath9k and ensures a fair beacon distribution when there are multiple IBSS stations. Also CWmin is quadrupled to achieve the expected percentage of distribution. Signed-off-by: Vivek Natarajan <vnatarajan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: properly use the mac80211 rate control apiFelix Fietkau2009-11-28
| | | | | | | | | | | This patch changes ath9k to pass proper MCS indexes and flags between the RC and the rest of the driver code. sc->cur_rate_table remains, as it's used by the RC code internally, but the rest of the driver code no longer uses it, so a potential new RC for ath9k would not have to update it. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* ath9k: rename ath_beaconq_setup() to ath9k_hw_beaconq_setup()Luis R. Rodriguez2009-10-07
| | | | | | | And move it to hw code on mac.c where it belongs. Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
* atheros: move tx/rx chainmask to ath_commonLuis R. Rodriguez2009-10-07
| | | | | Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>