The return value of the tx operation is commonly
misused by drivers, leading to errors. All drivers
will drop frames if they fail to TX the frame, and
they must also properly manage the queues (if they
didn't, mac80211 would already warn).

Removing the ability for drivers to return a BUSY
value also allows significant cleanups of the TX
TX handling code in mac80211.

Note that this also fixes a bug in ath9k_htc, the
old "return -1" there was wrong.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Tested-by: Sedat Dilek <sedat.dilek@googlemail.com> [ath5k]
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com> [rt2x00]
Acked-by: Larry Finger <Larry.Finger@lwfinger.net> [b43, rtl8187, rtlwifi]
Acked-by: Luciano Coelho <coelho@ti.com> [wl12xx]
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When op_flush() is called with no drop (drop=false), the driver
tries to tx as many frames as possible in about 100ms on every
hw queue. During this time period frames from sw queue are also
scheduled on to respective hw queue.
Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The DMA latency issue is observed only in Intel pinetrail platforms
but in the driver we had a default PM-QOS value of 55. This caused
unnecessary power consumption and battery drain in other platforms.

Remove the pm-qos thing in the driver code and address the throughput
issue in Intel pinetrail platfroms in user space using any one of
the scripts in below links:

http://www.kernel.org/pub/linux/kernel/people/mcgrof/scripts/cpudmalatency.c
http://johannes.sipsolutions.net/files/netlatency.c.txt

More details can be found in the following bugzilla link:

https://bugzilla.kernel.org/show_bug.cgi?id=27532

This reverts the following commits:

	98c316e3
	4dc3530d
	10598c12Signed-off-by: NMohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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 57c4d7b4.
Signed-off-by: NSteve Brown <sbrown@cortland.com>
Reviewed-by: NMohammed Shafi <shafi.ath9k@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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

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

Since even with the latest changes the false positive issue of the baseband
hang check is not fully solved yet, additional checks are needed.
If the baseband hang occurs, the rx_clear signal will be stuck to high, so
we can use the cycle counters to confirm it.
With this patch, a hardware reset is only triggered if the baseband hang
check returned true three times in a row, with a beacon interval between
each check and if the busy time was also 99% or more during the check
intervals.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch reverts the following commit
ath9k: remove bfs_paprd_timestamp from struct ath_buf_state

Under high interference/noisy environment conditions where PAPRD frames
fails heavily introduces a possibility of double freeing skb's and causes
kernel panic after some time.This patch reverts back to the original approach
of using paprd_timestamp before freeing the PAPRD frame skb's

[  194.193705] Pid: 0, comm: swapper Tainted: G      D WC
2.6.35-22-generic #33-Ubuntu
[  194.193712] Call Trace:
[  194.193722]  [<c05c6468>] ? printk+0x2d/0x35
[  194.193732]  [<c05c63c3>] panic+0x5a/0xd2
[  194.193741]  [<c05ca3ed>] oops_end+0xcd/0xd0
[  194.193750]  [<c0105f74>] die+0x54/0x80
[  194.193758]  [<c05c9a16>] do_trap+0x96/0xc0
[  194.193837]  [<c0103fb0>] ? do_invalid_op+0x0/0xa0
[  194.193846]  [<c010403b>] do_invalid_op+0x8b/0xa0
[  194.193856]  [<c020bd4c>] ? kfree+0xec/0xf0
[  194.193866]  [<c012ce18>] ? default_spin_lock_flags+0x8/0x10
[  194.193877]  [<c01de47a>] ? free_one_page+0x12a/0x2d0
[  194.193888]  [<c01e04dc>] ? __free_pages+0x1c/0x40
[  194.193897]  [<c05c97a7>] error_code+0x73/0x78
[  194.193906]  [<c020bd4c>] ? kfree+0xec/0xf0
[  194.193915]  [<c04ecdd0>] ? skb_release_data+0x70/0xa0
[  194.193924]  [<c04ecdd0>] skb_release_data+0x70/0xa0
[  194.193933]  [<c04ec997>] __kfree_skb+0x17/0x90
[  194.193941]  [<c04eca31>] consume_skb+0x21/0x40
[  194.193964]  [<f85e0b70>] ieee80211_tx_status+0x760/0x860 [mac80211]
[  194.193979]  [<f85caddf>] ath_tx_complete_buf+0x1bf/0x2c0 [ath9k]
[  194.193988]  [<c05c8b9f>] ? _raw_spin_lock_irqsave+0x2f/0x50
[  194.193997]  [<c04ec40e>] ? skb_queue_tail+0x3e/0x50
[  194.194010]  [<f85cc803>] ath_tx_complete_aggr+0x823/0x940 [ath9k]
[  194.194021]  [<c0108a28>] ? sched_clock+0x8/0x10
[  194.194030]  [<c016bf14>] ? sched_clock_local+0xa4/0x180
[  194.194040]  [<c0139f57>] ? enqueue_sleeper+0x1e7/0x2b0
[  194.194051]  [<c013a194>] ? enqueue_entity+0x174/0x200
[  194.194064]  [<f85ce83d>] ath_tx_edma_tasklet+0x2bd/0x3b0 [ath9k]
[  194.194074]  [<c05c8b9f>] ? _raw_spin_lock_irqsave+0x2f/0x50
[  194.194088]  [<f85c7b9f>] ath9k_tasklet+0x9f/0x190 [ath9k]
[  194.194097]  [<c01505d7>] tasklet_action+0xa7/0xb0
[  194.194107]  [<c015127c>] __do_softirq+0x9c/0x1b0
[  194.194117]  [<c01a7f64>] ? irq_to_desc+0x14/0x20
[  194.194126]  [<c0124fc4>] ? ack_apic_level+0x64/0x1f0
[  194.194136]  [<c01513d5>] do_softirq+0x45/0x50
[  194.194145]  [<c0151545>] irq_exit+0x65/0x70
[  194.194153]  [<c05cf665>] do_IRQ+0x55/0xc0
[  194.194162]  [<c016a6c7>] ? hrtimer_start+0x27/0x30
[  194.194171]  [<c0103630>] common_interrupt+0x30/0x38
[  194.194181]  [<c012c21a>] ? native_safe_halt+0xa/0x10
[  194.194268]  [<c010a2f9>] default_idle+0x49/0xb0
[  194.194277]  [<c0101fcc>] cpu_idle+0x8c/0xd0
[  194.194286]  [<c05b2431>] rest_init+0x71/0x80
[  194.194295]  [<c081981a>] start_kernel+0x36e/0x374
[  194.194305]  [<c08199dd>] ? pass_all_bootoptions+0x0/0xa
[  194.194314]  [<c08190d7>] i386_start_kernel+0xd7/0xdf
[  194.194364] panic occurred, switching back to text console
Signed-off-by: NMohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The beaconing vif addition is based on max beacon slot
available. So it is better to reserve a beacon slot
on interface addition and let it be configured properly
on bss_info change.
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The opmode recalculation is accessing hw registers.
When it is called from remove interface callback and
if there are no vifs present then hw is moved to FULL SLEEP
by radio disable. So use power save wrappers before
accessing hw registers in calculating opmode state.
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

move ath_update_txpow to common to remove code duplication
in both ath9k & ath9k_htc.
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

free the skb's when the Tx of PAPRD frames fails and also add a debug
message indicating that.
Signed-off-by: NMohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

free the skb's when the Tx of PAPRD frames fails and also add a debug
message indicating that.
Signed-off-by: NMohammed Shafi Shajakhan <mshajakhan@atheros.com>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When this PLL hang issue is seen, both Rx and Tx fail to work.
The sqsum_dvc needs to be below 2000 for a good chip. During
this issue the sqsum_dvc value is beyond 80000 and only a
full reset can solve this problem.
Signed-off-by: NVivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

With this change, less CPU time is spent trying to look for consecutive
pages for rx skbs. This also reduces the socket memory required for IP/UDP
reassembly.
Only two buffers per frame are supported. Frames spanning more buffers
will be dropped, but the buffer size is enough to handle the required
AMSDU size.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.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>

Instead of spreading ath_wake_mac80211_queue() calls over multiple places
in the tx path that process the tx queue for completion, call it only
where the pending frames counter gets decremented, eliminating some
redundant checks.
To prevent queue draining from waking the queues prematurely (e.g. during
a hardware reset), reset the queue stop state when draining all queues,
as the caller in main.c will run ieee80211_wake_queues(hw) anyway.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

While unloading the driver, the ps_usecount is incremented
before configuring gpio registers in deinit_device.
But it is failed to restore the ps_usecount after that.
The problem is that the chip is forcibly moved to FULL SLEEP
by radio_disable when mac80211 is reporting as idle
though ps_usecount is not zero.

This patch retores ps_usecount properly and ensures that
the chip is always moved to full sleep only if ps usage
count is zero which also helps in debugging deadbeef on
multivif case. And also fixes the following warning.

ath: DMA failed to stop in 10 ms AR_CR=0xdeadbeef AR_DIAG_SW=0xdeadbeef
ath: Could not stop RX, we could be confusing the DMA engine when we
start RX up
------------[ cut here ]------------
WARNING: at drivers/net/wireless/ath/ath9k/recv.c:536
ath_stoprecv+0xf4/0x100 [ath9k]()

Cc: stable@kernel.org
Cc: Paul Stewart <pstew@google.com>
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We do not kill any scheduled tasklets when stopping device, that may
cause usage of resources after free. Moreover we enable interrupts
in tasklet function, so we could potentially end with interrupts
enabled when driver is not ready to receive them.

I think patch should fix Ben's kernel crash from:
http://marc.info/?l=linux-wireless&m=129438358921501&w=2

Cc: stable@kernel.org
Signed-off-by: NStanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The stations hold the ath_node, which holds the tid
and other xmit logic structures.  In order to debug
stuck xmit logic, we need a way to print out the tid
state for the stations.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There are several places where ath_reset() was called without proper
calls to ath9k_ps_wakeup/ath9k_ps_restore. To fix this, add those calls
directly to ath_reset and drop them from callers where it makes sense.

Also add them to the config callback around ath_update_txpow to fix a
crash that happens when the tx power changed before any vif is brought up.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The aggregation code currently doesn't implement the
buffer size negotiation. It will always request a max
buffer size (which is fine, if a little pointless, as
the mac80211 code doesn't know and might just use 0
instead), but if the peer requests a smaller size it
isn't possible to honour this request.

In order to fix this, look at the buffer size in the
addBA response frame, keep track of it and pass it to
the driver in the ampdu_action callback when called
with the IEEE80211_AMPDU_TX_OPERATIONAL action. That
way the driver can limit the number of subframes in
aggregates appropriately.

Note that this doesn't fix any drivers apart from the
addition of the new argument -- they all need to be
updated separately to use this variable!
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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

Since baseband hangs are rare, but the hang check function has a high
false positive rate in some situations, we need to add more reliable
indicators.

In AP mode we can use blocked beacon transmissions as an indicator,
they should be rare enough.

In station mode, we can skip the hang check entirely, since a true
hang will trigger beacon loss detection, and mac80211 will rescan,
which leads to a hw reset that will bring the hardware back to life.

To make this more reliable, we need to skip fast channel changes
if the hardware appears to be stuck.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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

Restart the beacon timers only if the beacon
was already configured. Otherwise beacons timers
are restarted unnecessarily in unassociated state too.

Cc: stable@kernel.org
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Disabling BH is not required while running from a tasklet context
and so replace spin_lock_bh with just spin_lock.
Signed-off-by: NSenthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There is a missing unlock when we hit the "No beacon slot available"
error condition.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

ath9k supports its own set of virtual wiphys, and it uses
the mac80211 idle notifications to know when a device needs
to be idle or not. We recently changed ath9k to force idle
on driver stop() and on resume but forgot to take into account
ath9k's own virtual wiphy idle states. These are used internally
by ath9k to check if the device's radio should be powered down
on each idle call. Without this change its possible that the
device could have been forced off but the virtual wiphy idle
was left on.

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>

Restricting the chainmask to 1 for legacy mode disables useful features
such as MRC, and it reduces the available transmit power.
I can't think of a good reason to do this in legacy mode, so let's just
get rid of that code.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Target Tx power available in eeprom is for PAPRD. If PAPRD
fails, paprd scale factor needs to be detected from this
target tx power.
Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

PM-QOS value can be user specified via module parameter.
This patch adds few comments regarding this in the driver
code.
Signed-off-by: NMohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch allows the pm-qos value to be user configurable by making it as
a module parameter.This will help our customers to configure the pm-qos
value according to the effect in throughput due to the DMA latency problem
which was observed in Intel Pinetrail platforms.
	The tested value of '55' will be filled as the default
pm-qos-value incase the user does not specifies pm-qos value as a
module parameter.
example usage: sudo modprobe ath9k pmqos=65

Cc: Senthilkumar Balasubramanian <Senthilkumar.Balasubramanian@Atheros.com>
Signed-off-by: NMohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The EEPROM contains scale factors for the tx power, which define
the range of allowable difference between target power and training
power. If the difference is too big, PA predistortion cannot be used.
For 2.4 GHz there is only one scale factor, for 5 GHz there are
three, depending on the specific frequency range.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

To be able to measure the thermal values correctly for PAPRD, we need
to send training frames before setting up the gain table for the measurement,
and then again afterwards for the actual training.

For further improvement, send training frames at MCS0 instead of 54 MBit/s
legacy. That way we can use the No-ACK flag for the transmission, which
speeds up PAPRD training in general, as the hardware won't have to
retransmit and wait for ACK timeout (was previously set to 4 * 6
transmission attempts).
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The HW has to be awake when accessing registers.
Signed-off-by: NSujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>