e.g.

usb 1-7: rx_urb_complete() *** first fragment ***
usb 1-7: rx_urb_complete() *** second fragment ***
drivers/net/wireless/zd1211rw/zd_mac.c:1063 ASSERT
(((current_thread_info()->preempt_count) & (((1UL << (12))-1) << ((0 +
8) + 8)))) VIOLATED!
 [<f0299448>] zd_mac_rx+0x3e7/0x47a [zd1211rw]
 [<f029badc>] rx_urb_complete+0x22d/0x24a [zd1211rw]
 [<b028a22f>] urb_destroy+0x0/0x5
 [<b01f0930>] kref_put+0x65/0x72
 [<b0288cdf>] usb_hcd_giveback_urb+0x28/0x57
 [<b02950c4>] qh_completions+0x296/0x2f6
 [<b0294b21>] ehci_urb_done+0x70/0x7a
 [<b0294ea1>] qh_completions+0x73/0x2f6
 [<b02951bc>] ehci_work+0x98/0x538

Remove the bogus assertion, and use dev_kfree_skb_any as pointed out by
Ulrich Kunitz.
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This adds zd1211rw driver support for the softmac functionality I
added a while back. We now obey changes in basic rates, use short
preamble if it is available (but long if the AP says it's not),
and send self-CTS in the proper situations.

Locking fixed and improved by Ulrich Kunitz.
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

These controlset rate constants are also applicable in places outside
the controlset, such as in the RTS/CTS control register.
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Bit-field constants in zd_chip.h are now defined using a shift expression.
The value 0x08 is now (1 << 3). The fix is intended to improve readability.

Remove misleading comment in zd_mac.c: The function already returns -EPERM
in managed mode (IW_MODE_INFRA).

Remove unused code in zd_mac.c: The unused code intended for debugging
rx_status values is no longer useful.

Added dump_stack() to ZD_ASSERT macro: Output of the stack helps to debug
assertions. Keep in mind that the ZD_ASSERT() macro only results in code,
if DEBUG is defined.

Improved comments for filter_rx()

zd_usb.c: Added driver name to module init and exit functions
Signed-off-by: NUlrich Kunitz <kune@deine-taler.de>
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

http://bugzilla.kernel.org/show_bug.cgi?id=7399

zd1211rw's support for IW_FREQ_AUTO is broken: when specified, the driver
tries to change to a channel specified in an uninitialized integer. As
IW_FREQ_AUTO is hard to implement properly, the solution (at least for now)
is to drop support for it and start ignoring the flags like all other wireless
drivers do.

This has the added advantage that kismet also starts working with zd1211rw,
even though kismet requesting IW_FREQ_AUTO is also a bug (fixed in their svn)
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This reverts commit 4e1bbd84.

Quoth Daniel Drake <dsd@gentoo.org>:

"A user reported that commit 4e1bbd84
(Remove unneeded packed attributes) breaks the zd1211rw driver on ARM."
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The break was caused by 7c28ad2d.
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch includes a big cleanup of the existing unused LED code,
and adds support for controlling the LED.

The link LED will blink if the device is not associated. The LED
switches between 2 seconds on and 1 second off. If the device is
associated the LED is switched on.

The link LED also indicates packet TX. I do a little bit more led
resetting than the vendor driver, but the device works now as
expected for single LED and double LED devices.
Signed-off-by: NUlrich Kunitz <kune@deine-taler.de>
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Inspired by an e-mail by Stephen Hemminger I decided to remove all
unneeded packed attributes from the code where the member variables are
already aligned. This avoids horrible code being generated on some
architectures.
Signed-off-by: NUlrich Kunitz <kune@deine-taler.de>
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Caused by a documentation issue I mixed up fields of the zd_status
structure. This patch fixes it and improves also the average
computation, which is now using only measurements of packets sent
by the access point.
Signed-off-by: NUlrich Kunitz <kune@deine-taler.de>
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add static to 2 internal functions. Thanks goes to Adrian Bunk, who found that.

Also made some modifications to the clear functions:

After a discussion on the mailing list, I implemented this code to
have on the one hand sufficient test in debug mode, but on the
other hand reduce the overhead for structure clearing to a
minimum.

A new macro ZD_MEMCLEAR is introduced, which produces code if
DEBUG is set. Locks are not set anymore for structure clearing,
but in debug mode, there is a verification, that the locks have
not been set.

Finally, removed a misleading comment regarding locking in the disconnect
path.
Signed-off-by: NUlrich Kunitz <kune@deine-taler.de>
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

I had problems with my AVM Fritz!Box access point. It appeared
that the AP deauthorized me and the softmac didn't reconnect me.
This patch handles the problem.
Signed-off-by: NUlrich Kunitz <kune@deine-taler.de>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Apparently the ZD1211 doesn't mind, but the ZD1211B absolutely must be
told that encryption is happening in software.
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NUlrich Kunitz <kune@deine-taler.de>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We'll be needing these at some point...
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NUlrich Kunitz <kune@deine-taler.de>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There has been a problem in the radiotap header. Monitor mode
works now with tcpdump 3.94 + libpcap 0.9.4. ethereal 0.99.0 +
libpcap 0.9.4 is broken, because it doesn't find the right offset
for the IEEE 802.11 header.
Signed-off-by: NUlrich Kunitz <kune@deine-taler.de>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This avoids some potential races.
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There are 60+ USB wifi adapters available on the market based on the ZyDAS
ZD1211 chip.

Unlike the predecessor (ZD1201), ZD1211 does not have a hardware MAC, so most
data operations are coordinated by the device driver. The ZD1211 chip sits
alongside an RF transceiver which is also controlled by the driver. Our driver
currently supports 2 RF types, we know of one other available in a few marketed
products which we will be supporting soon.

Our driver also supports the newer revision of ZD1211, called ZD1211B. The
initialization and RF operations are slightly different for the new revision,
but the main difference is 802.11e support. Our driver does not support the
QoS features yet, but we think we know how to use them.

This driver is based on ZyDAS's own GPL driver available from www.zydas.com.tw.
ZyDAS engineers have been responsive and supportive of our efforts, so thumbs
up to them. Additionally, the firmware is redistributable and they have
provided device specs.

This driver has been written primarily by Ulrich Kunitz and myself. Graham
Gower, Greg KH, Remco and Bryan Rittmeyer have also contributed. The
developers of ieee80211 and softmac have made our lives so much easier- thanks!

We maintain a small info-page: http://zd1211.ath.cx/wiki/DriverRewrite

If there is enough time for review, we would like to aim for inclusion in
2.6.18. The driver works nicely as a STA, and can connect to both open and
encrypted networks (we are using software-based encryption for now). We will
work towards supporting more advanced features in the future (ad-hoc, master
mode, 802.11a, ...).
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>