For some reason firmware is sending invalid rates when we try to
query current bitrate from ath6kl_get_station() and a warning is issued:

[ 3810.415720] ath6kl: invalid rate: 1935633515
[ 3811.105493] ath6kl: invalid rate: 1935633515
[ 3811.556063] ath6kl: invalid rate: 1935633515

As the warning happens way too often, convert the warning to a debug
message once we have a proper fix. But to make it easy to follow
how often the problem appears, add a debugfs to print
various statistics about workarounds and make this issue the first WAR.
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

To write a value to register:
echo <register_offset>=<register_value> > <degfs_root>/ieee80211/phyX/ath6kl/reg_write

kvalo: rename file to reg_write to follow the style of other debugfs files
Signed-off-by: NVasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

Firmware initiates roaming only after it reaches a rssi of 20.
This lower rssi threshold can be modified through a wmi command
to modify the roaming behavior.

kvalo: rename debugfs functions and move comment about rssi units next to
ath6kl_wmi_set_roam_lrssi_cmd()
Signed-off-by: NVivek Natarajan <nataraja@qca.qualcomm.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

To dump a particular register:

    echo <reg_addr> > <debugfs_root>/ieee80211/phyX/ath6kl/reg_addr

To dump the entire register set:

    echo 0 > <debugfs_root>/ieee80211/phyX/ath6kl/reg_addr

Register values will be available at:

    cat <debugfs_root>/ieee80211/phyX/ath6kl/reg_dump

kvalo: commit log cleanup, renamed few functions, removed a warning
message
Signed-off-by: NVasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

Firmare sends the logs only when it's internal ring buffer is full. But
if firmware crashes we need to retrieve the latest logs through diagnose
window. This is now done everytime the debugfs file is read.
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

Firmware log parameters can be controlled now with help of fwlog_mask
debugfs file.
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

Firmware sends binary logs with WMIX_DBGLOG_EVENTID event. Create
a buffer which stores the latest logs and which can be copied from
fwlog debugfs file with cp command.

To save memory firmware log support is enabled only when CONFIG_ATH6KL_DEBUG
is enabled.
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

It would be at <dbgfs_root>/ieee80211/phyX/ath6kl/credit_dist_stats.
Signed-off-by: NVasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

It would be at <debugfs_root>/ieee80211/phyX/ath6kl/tgt_stats.
Signed-off-by: NVasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

Just initial debugfs changes. The debugfs directory would
be created at <debugfs_root>/ieee80211/phyX/ath6kl.
Signed-off-by: NVasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

Last May we started working on cleaning up ath6kl driver which is
currently in staging. The work has happened in a separate
ath6kl-cleanup tree:

http://git.kernel.org/?p=linux/kernel/git/kvalo/ath6kl-cleanup.git;a=summary

After over 1100 (!) patches we have now reached a state where I would
like to start discussing about pushing the driver to the wireless
trees and replacing the staging driver.

The driver is now a lot smaller and looks like a proper Linux driver.
The size of the driver (measured with simple wc -l) dropped from 49
kLOC to 18 kLOC and the number of the .c and .h files dropped from 107
to 22. Most importantly the number of subdirectories reduced from 26
to zero :)

There are two remaining checkpatch warnings in the driver which we
decided to omit for now:

drivers/net/wireless/ath/ath6kl/debug.c:31:
  WARNING: printk() should include KERN_ facility level
drivers/net/wireless/ath/ath6kl/sdio.c:527:
  WARNING: msleep < 20ms can sleep for up to 20ms;
  see Documentation/timers/timers-howto.txt

The driver has endian annotations for all the hardware specific
structures and there are no sparse errors. Unfortunately I don't have
any big endian hardware to test that right now.

We have been testing the driver both on x86 and arm platforms. The
code is also compiled with sparc and parisc cross compilers.

Notable missing features compared to the current staging driver are:

o HCI over SDIO support
o nl80211 testmode
o firmware logging
o suspend support

Testmode, firmware logging and suspend support will be added soon. HCI
over SDIO support will be more difficult as the HCI driver needs to
share code with the wifi driver. This is something we need to research
more.

Also I want to point out the changes I did for signed endian support.
As I wasn't able to find any support for signed endian annotations I
decided to follow what NTFS has done and added my own. Grep for sle16
and sle32, especially from wmi.h.

Various people have been working on the cleanup, the hall of
fame based on number of patches is:

   543  Vasanthakumar Thiagarajan
   403  Raja Mani
   252  Kalle Valo
    16  Vivek Natarajan
    12  Suraj Sumangala
     3  Joe Perches
     2  Jouni Malinen
Signed-off-by: NVasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: NRaja Mani <rmani@qca.qualcomm.com>
Signed-off-by: NVivek Natarajan <nataraja@qca.qualcomm.com>
Signed-off-by: NSuraj Sumangala <surajs@qca.qualcomm.com>
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>