The new PCU lock is better placed so we can just contend
against that when trying to reset hardware.

This is part of a series of patches which fix stopping
TX DMA completley when requested on the driver.
For more details about this issue refer to this thread:

http://marc.info/?l=linux-wireless&m=128629803703756&w=2Tested-by: NBen Greear <greearb@candelatech.com>
Cc: Kyungwan Nam <kyungwan.nam@atheros.com>
Cc: stable@kernel.org
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

ANI needs the RSSI average only in station mode, and only for tracking
the signal strength of beacons of the AP that it is connected to.
Adjust the code to track on the beacon RSSI, and store the average of that
in the ath_wiphy struct.
With these changes, we can get rid of this extra station lookup in the
rx path, which saves precious CPU cycles.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The real way to lock RX is to contend on the PCU
and reset, this will be fixed in the next patch but for
now just do the renames so that the next patch which changes
the locking order is crystal clear.

This is part of a series that will help resolve the bug:

https://bugzilla.kernel.org/show_bug.cgi?id=14624

For more details about this issue refer to:

http://marc.info/?l=linux-wireless&m=128629803703756&w=2

Cc: stable@kernel.org
Cc: Ben Greear <greearb@candelatech.com>
Cc: Kyungwan Nam <kyungwan.nam@atheros.com>
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Tested-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Set the rate table in the rc module properly based on band and
HT capabilities instead, which was already partially done, but
not for every mode.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Results for the active channel are updated whenever a new survey dump
is requested, the old data is kept to allow multiple processes to
make their own channel utilization averages.
All other channels only contain the data for the last time that the
hardware was on the channel, i.e. the last scan result or other
off-channel activity.
Running a background scan does not clear the data for the active
channel.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drv_config callback is called only after the ack for the nullframe
is received and so driver need not do anything special for this.

So remove NULLFUNC_COMPLETED, PS_ENABLED flags and bf_isnullfunc
flags from ath9k as mac80211 already handles them properly.
Signed-off-by: NSenthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

It is not used anywhere else and can be made static
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

A new aggregation session start can be issued by mac80211, even when the
cleanup of the previous session has not completed yet. Since the data structure
for the session is not recreated, this could corrupt the block ack window
and lock up the aggregation session. Fix this by delaying the new session
until the old one has been cleaned up.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There's no reason to keep pointers to pending tx buffers around, if they're
only used to keep track of which frames are still pending. Use a bitfield
instead.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

ath9k's entire logic with SC_OP_SCANNING is incorrect due to the
way mac80211 currently implements the scan complete callback and
we handle it in ath9k. This patch removes the flag completely in
preference for the SC_OP_OFFCHANNEL which is really what we wanted.

The scanning flag was used to ensure we reset ANI to the old values
when we go back to the home channel, but if we are offchannel we
use some defaults. The flag was also used to re-enable the TX monitor.

Without this patch we simply never re-enabled ANI and the TX monitor
after going offchannel. This means that after one background
scan we are prone to noise issues and if we had a TX hang we would
not recover. To get this to work properly we must enable ANI after
we have configured the beacon timers, otherwise hardware acts really
oddly.

This patch has stable fixes which apply down to [2.6.36+], there
*may* be a to fix this on older kernels but requires a bit of
work since this patch relies on the new mac80211 flag
IEEE80211_CONF_OFFCHANNEL which was introduced as of 2.6.36.

Cc: stable@kernel.org
Cc: Paul Stewart <pstew@google.com>
Cc: Amod Bodas <amod.bodas@atheros.com>
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

At the time the .add_interface driver op is called, the interface has not
been marked as running yet, so ieee80211_iterate_active_interfaces will
not pass it to the iterator function.
Because of this, the calculated BSSID mask is wrong, which breaks multi-BSS
operation.

Additionally, the current way of comparing all addresses against each other
is pointless, as the hardware only uses the hardware MAC address and the BSSID
mask for matching the destination address, so all the address array
reallocation is completely unnecessary.

This patch simplifies the logic by setting the initial mask bytes to 0xff
and removing all bits in the iterator call that don't match the hardware MAC
address. It also calls the iterator for the vif that was passed to
add_interface()
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Tested-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This algorithm chooses the best main and alt lna out of
LNA1, LNA2, LNA1+LNA2 and LNA1-LNA2 to improve rx for single
chain chips(AR9285). This would greatly improve rx when there
is only one antenna is connected with AR9285.
Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NVivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When the noise floor limits are being bypassed because of strong
interference, sensitivity is also reduced.
In order to recover from this as quickly as possible, trigger a
long periodic calibration every second instead of every 30 seconds,
until the NF median is within limits again. This is especially important
if the interference lasts for a while, since it takes multiple clean
NF calibrations to bring the median back to normal.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The noise floor history buffer is currently not kept per channel, which
can lead to problems when changing channels from a clean channel to a
noisy one. Also when switching from HT20 to HT40, the noise floor
history buffer is full of measurements, but none of them contain data
for the extension channel, which it needs quite a bit of time to recover
from.

This patch puts all the per-channel calibration data into a single data
structure, and gives the the driver control over whether that is used
per-channel or even not used for some channels.

For ath9k_htc, I decided to keep this per-channel in order to avoid
creating regressions.

For ath9k, the data is kept only for the operating channel, which saves
some space. ath9k_hw takes care of wiping old data when the operating
channel or its channel flags change.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Previously the software scan callback was used to indicate to the hardware,
when it was safe to calibrate. This didn't really work properly, because it
depends on a specific order of software scan callbacks vs. channel changes.
Also, software scans are not the only thing that triggers off-channel
activity, so it's better to use the newly added indication from mac80211 for
this and not use the software scan callback for anything calibration related.

This fixes at least some of the invalid noise floor readings that I've seen
in AP mode on AR9160
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Sometimes txq state(txq->stopped) can be marked as started but the actual
queue may not be started (in ATH_WIPHY_SCAN state, for example). Fix this.
Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

ath9k_hw_check_alive() occasionally returns false, as the hardware
is still processing data in a specific state. Fix this issue by
repeating the test a few times with longer delay inbetween attempts.
This gets rid of excessive hardware resets that appear frequently on
some AR9132 based devices, but could also happen on AR9280.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Reported-by: NBjörn Smedman <bjorn.smedman@venatech.se>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

It is possbile that the transmission of paprd test frame
might not get completed in 100ms if tx is stuck. Freeing
this skb upon timeout in ath_paprd_calibrate() will result
in accessing already freed memory when the associated pending
buffer is drained in txq. This patch fixes this issue.
Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There are few places where ANI is started without checking
if it is right to start. This might lead to a case where ani
timer would be left undeleted and cause improper memory acccess
during module unload. This bug is clearly exposed with
paprd support where the driver detects tx hang and does a
chip reset. During this reset ani is (re)started without checking
if it needs to be started. This would leave a timer scheduled
even after all the resources are freed and cause a panic.

This patch introduces a bit in sc_flags to indicate if ani
needs to be started in sw_scan_start() and ath_reset().
This would fix the following panic. This issue is easily seen
with ar9003 + paprd.

 BUG: unable to handle kernel paging request at 0000000000003f38
[<ffffffff81075391>] ? __queue_work+0x41/0x50
[<ffffffff8106afaa>] run_timer_softirq+0x17a/0x370
[<ffffffff81088be8>] ? tick_dev_program_event+0x48/0x110
[<ffffffff81061f69>] __do_softirq+0xb9/0x1f0
[<ffffffff810ba060>] ? handle_IRQ_event+0x50/0x160
[<ffffffff8100af5c>] call_softirq+0x1c/0x30
[<ffffffff8100c9f5>] do_softirq+0x65/0xa0
[<ffffffff81061e25>] irq_exit+0x85/0x90
[<ffffffff8155e095>] do_IRQ+0x75/0xf0
[<ffffffff815570d3>] ret_from_intr+0x0/0x11
<EOI>
[<ffffffff812fd67b>] ? acpi_idle_enter_simple+0xe4/0x119
[<ffffffff812fd674>] ? acpi_idle_enter_simple+0xdd/0x119
[<ffffffff81441c87>] cpuidle_idle_call+0xa7/0x140
[<ffffffff81008da3>] cpu_idle+0xb3/0x110
[<ffffffff81550722>] start_secondary+0x1ee/0x1f5
Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Some vendors require the LED to be ON always irrespective of any
radio activity. Introducing a module parameter to disable blinking,
so that one can choose between always on or led blink during
activity.
Signed-off-by: NVivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

ath9k tries to prevent WMM queue tx buffer starvation caused by
traffic on different queues by limiting the number of pending frames
in a tx queue (tracked in the ath_buf structure). This had a leak
issue, because the a skb can be reassigned to a different ath_buf
in the tx path, causing the pending frame counter to become inaccurate.

To fix this, track the number of frames in an array in the softc,
using the mac80211 queue mapping as index.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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

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

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

ath_get_mac80211_qnum() expects the queue 'subtype'
(internal ID for the WMM AC) as argument when looking up
the mac80211 queue, however ath_wake_mac80211_queue provides
txq->axq_qnum instead, which contains the hardware queue
number. Fix this by keeping track of the WMM class ID in
the txq data structure.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This adds support for ANI for AR9003. The implementation for
ANI for AR9003 is slightly different than the one used for
the older chipset families. It can technically be used for
the older families as well but this is not yet fully tested
so we only enable the new ANI for the AR5008, AR9001 and AR9002
families with a module parameter, force_new_ani.

The old ANI implementation is left intact.

Details of the new ANI implemention:

  * ANI adjustment logic is now table driven so that each ANI level
    setting is parameterized. This makes adjustments much more
    deterministic than the old procedure based logic and allows
    adjustments to be made incrementally to several parameters per
    level.

  * ANI register settings are now relative to INI values; so ANI
    param zero level == INI value. Appropriate floor and ceiling
    values are obeyed when adjustments are combined with INI values.

  * ANI processing is done once per second rather that every 100ms.
    The poll interval is now a set upon hardware initialization and
    can be picked up by the core driver.

  * OFDM error and CCK error processing are made in a round robin
    fashion rather than allowing all OFDM adjustments to be made
    before CCK adjustments.

  * ANI adjusts MRC CCK off in the presence of high CCK errors

  * When adjusting spur immunity (SI) and OFDM weak signal detection,
    ANI now sets register values for the extension channel too

  * When adjusting FIR step (ST), ANI now sets register for FIR step
    low too

  * FIR step adjustments now allow for an extra level of immunity for
    extremely noisy environments

  * The old Noise immunity setting (NI), which changes coarse low, size
    desired, etc have been removed. Changing these settings could affect
    up RIFS RX as well.

  * CCK weak signal adjustment is no longer used

  * ANI no longer enables phy error interrupts; in all cases phy hw
    counting registers are used instead

  * The phy error count (overflow) interrupts are also no longer used
    for ANI adjustments. All ANI adjustments are made via the polling
    routine and no adjustments are possible in the ISR context anymore

  * A history settings buffer is now correctly used for each channel;
    channel settings are initialized with the defaults but later
    changes are restored when returning back to that channel

  * When scanning, ANI is disabled settings are returned to (INI) defaults.

  * OFDM phy error thresholds are now 400 & 1000 (errors/second units) for
    low/high water marks, providing increased stability/hysteresis when
    changing levels.

  * Similarly CCK phy error thresholds are now 300 & 600 (errors/second)
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Because there is a limited number of tx buffers available, once the
queue has been filled to a certain point, ath9k needs to stop accepting
new frames from mac80211. In order to prevent a full WMM queue from
stopping another queue with fewer frames, this patch limits the number
of queued frames to a quarter of the total available tx buffers, minus
some reserved frames to be used for other purposes (e.g. beacons).

Because tx buffers are reserved for frames when they're staged in
software queues as well, the actual queue depth cannot be used for
this, so this patch stores a reference to the tx queue in the ath_buf
struct and keeps track of the total number of pending frames.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

A bunch of data structures are present in the
common module, which are internal to ath9k.
Move them to ath9k.h
Signed-off-by: NSujith <Sujith.Manoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Also add a function to clean up tx status ring.
Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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: NPavel Roskin <proski@gnu.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch passes in a pointer to the ath_tx_status data structure for
functions that need it, instead of letting them grab it directly from
the ath_desc struct. This is useful for making it possible to allocate
the intermediate tx status data separately.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The TIM timer interrupt is enabled even before the ACK of nullqos
is received which is unnecessary.

Also clean up the CONF_PS part of config callback properly for
better readability.
Signed-off-by: NSenthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Calling ath_bus_cleanup() after ieee80211_free_hw() resulted in access
to common->bus_ops, which is already freed as part of the device data.

Remove the cleanup field in struct ath_bus_ops, as it was never used
properly.  Remove ath_bus_cleanup().  Merge cleanup functions in place
of the ath_bus_cleanup() calls.  Take care not to use any device data
after ieee80211_free_hw().
Signed-off-by: NPavel Roskin <proski@gnu.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>