Add USB support for ar6004. Currently only firmware can be booted,
no commands can be sent to firmware yet as HTC layer doesn't work
with USB yet.

Based on patches by Kevin Fang.
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

SDIO and USB have different maximum sizes for BMI commands so make that
configurable.
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

In preparation for USB support which has it's own method for bmi.

Based on code by Kevin Fang.
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

The benefit from this is that user space can control hardware's power state
by putting interface up and down. This is handy if firmware gets to some
weird state.

The downside will be that putting interface up takes a bit longer,
I was measuring ~500 ms during interface up.
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

aht6kl core code will call the cleanup function when the device is removed.
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

Brent reported that ath6kl busy loops if firmware doesn't boot for some
reason (in this case he was using an older firmware which wasn't supported
by ath6kl).

Investigation revealed that this was even on purpose,
ath6kl_bmi_get_rx_lkahd() had a parameter to disable the timeout check,
which is extremely evil. I didn't find any reason why the timeout needs
to be disabled so I just removed the feature. The function already busyloops
a maximum of one second if it doesn't get an answer, even that's too long.
If something takes longer than that a more friendly approach is needed.
Reported-by: NBrent Taylor <btaylor1@motorolasolutions.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>