As part of the queue refactoring, change the queue callback
function names to have 3 different actions: start, kick & stop.

We can now also remove the STATE_RADIO_RX_ON/STATE_RADIO_RX_OFF
device_state flags, and replace the usage with using the
start_queue/stop_queue callback functions.
This streamlines the RX queue handling to the
similar approach as all other queues.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

As part of the queue refactoring, we now introduce
3 queue commands: start, kick, stop.

 - Start: will enable a queue, for TX this will
   not mean anything, while for beacons and RX
   this will update the registers to enable the queue.
 - Kick: This will kick all pending frames to
   the hardware. This is needed for the TX queue
   to push all frames to the HW after the queue
   has been started
 - Stop: This will stop the queue in the hardware,
   and cancel any pending work (So this doesn't
   mean the queue is empty after a stop!).

Move all code from the drivers into the appropriate
functions, and link those calls to the old rt2x00lib
callback functions (we will fix this later when we
refactor the queue control inside rt2x00lib).
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NJohannes Stezenbach <js@sig21.net>
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When an rt2x00 USB device is unplugged while in use, it reliably
hangs the whole system.  After some time the watchdog prints:

BUG: soft lockup - CPU#0 stuck for 64s! [kworker/u:0:5]
...
[<c01a88d8>] (usb_submit_urb+0x0/0x2ac) from [<bf0e752c>] (rt2x00usb_kick_rx_entry+0xb4/0xe8 [rt2x00usb])
[<bf0e7478>] (rt2x00usb_kick_rx_entry+0x0/0xe8 [rt2x00usb]) from [<bf0e7588>] (rt2x00usb_clear_entry+x28/0x2c [rt2x00usb])
[<bf0e7560>] (rt2x00usb_clear_entry+0x0/0x2c [rt2x00usb]) from [<bf0d5bc4>] (rt2x00lib_rxdone+0x2e0/0x2f8 [rt2x00lib])
[<bf0d58e4>] (rt2x00lib_rxdone+0x0/0x2f8 [rt2x00lib]) from [<bf0e7e00>] (rt2x00usb_work_rxdone+0x54/0x74 [rt2x00usb])
[<bf0e7dac>] (rt2x00usb_work_rxdone+0x0/0x74 [rt2x00usb]) from [<c00542b4>] (process_one_work+0x20c/0x35c)

Clear the DEVICE_STATE_PRESENT flag when usb_submit_urb()
returns -ENODEV to fix this.
Signed-off-by: NJohannes Stezenbach <js@sig21.net>
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

By not scheduling the TX/RX completion worker threads
when Radio is disabled, or hardware has been unplugged,
the queues cannot be completely cleaned.

This causes crashes when the hardware has been unplugged while
the radio is still enabled.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When the TX status handler failed to clear the queue
in rt2x00usb_watchdog_tx_dma() we shouldn't use a failsave
to use the rt2x00usb txdone handler.

If a driver has overriden the txdone handler it must make
sure the txdone handler is capable of cleaning up the queue itself.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Rename rt2x00queue_timeout to rt2x00queue_status_timeout to
better describe what is actually timing out (note that
we already have a rt2x00queue_dma_timeout).
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Acked-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

kill_urb guarentees that when the function returns, the URB has
been fully killed. This means we don't need the extra sleeping
after the call to kill_urb.

kill_urb can however also guarentee the submit_urb to fail, as
a result, we must catch the return value from submit_urb an
correctly mark the entry as owned by the driver, and the
status as broken.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The currently used watchdog functions cannot be applied
to empty queues.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

All access to the queue_entry->flags can be done concurrently,
so all flags must use the atomic operators. On most locations
this was already done, so just fix the last few non-atomic
versions.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

A lot of functions accept a struct rt2x00_dev combined with
either a struct queue_entry or struct data_queue argument.
This can be simplified by only passing on the queue/entry
argument.

In cases where rt2x00_dev and a sk_buff are send together,
we can send the queue_entry instead.

rt2x00usb_alloc_urb and rt2x00usb_free_urb have a bit
of vague naming. Instead they allocate all the data which
belongs to a rt2x00 data queue entry.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

rt2x00usb_watchdog_reset_tx performs the same task
as rt2x00usb_kill_tx_queue, with the only difference
is that it waits for all entries to be returned to
the driver and for all frames the status has been
reported to mac80211.

We can easily split this task by calling rt2x00usb_kill_tx_queue,
sleep for a short period and invoke the TX status reporting
function. By adding the sleep() to the kill_entry we make sure
that even during shutdown we guarentee the entry has been killed when
the function returns. To make this work correctly the interrupt
handlers have to be updated to prevent checking for the RADIO_ENABLED
flag too early which prevents the ownership of the entry to be reset.
Additionally a check for the DEVICE_PRESENT flag is not required but
is nice to prevent race conditions when the device was unplugged.

Additionally rather then calling rt2x00usb_work_txdone() for
status reporting we let the driver perform the TX status reporting
first. If this is not sufficient then rt2x00usb_work_txdone() will
still be used to cleanup the mess.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The watchdog for rt2800usb triggers frequently causing all URB's
to be canceled often enough to interrupt the normal TX flow.
More research indicated that not the URB upload to the USB host
were hanging, but instead the TX status reports.

To correctly detect what is going on, we introduce Q_INDEX_DMA_DONE
which is an index counter between Q_INDEX_DONE and Q_INDEX and indicates
if the frame has been transfered to the device.

This also requires the rt2x00queue timeout functions to be updated
to differentiate between a DMA timeout (time between Q_INDEX and
Q_INDEX_DMA_DONE timeout) and a STATUS timeout (time between
Q_INDEX_DMA_DONE and Q_INDEX_DONE timeout)

All Q_INDEX_DMA_DONE code was taken from the RFC from
Helmut Schaa <helmut.schaa@googlemail.com> for the implementation
for watchdog for rt2800pci.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

All access to queue->entries through the Q_INDEX/Q_INDEX_DONE
variables must be done using spinlock protection. It is best
to manage this completely from rt2x00queue.c.

For safely looping through all entries in the queue, the function
rt2x00queue_for_each_entry is added which will walk from from a index
range in a safe manner.

This also fixes rt2x00usb which walked the entries list from
0 to length to kill each entry (killing entries must be done
from Q_INDEX_DONE to Q_INDEX to enforce TX status reporting to
occur in the correct order.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Cosmetic change, reduce indenting.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Acked-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

write_tx_desc shouldn't pass a rt2x00dev and skb pointer,
instead it should use the same format as other TX frame
callback functions, which is passing the data_entry pointer
which contains all the information which is needed to work
on a TX frame.

Most callers of the kick_tx_queue and kill_tx_queue already
have the data_queue pointer, so rather then sending the QID
with the given function, when the driver requests a new
pointer to the data_queue, it is more efficient to just
send the data_queue pointer directly.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

At some points, some drivers can't report the full TX status
information. This can happen for the UNKNOWN state, or the
FAILURE state (in case the URB failed).
Add a wrapper function to simplify reporting the
empty TX information.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Move all TX and RX completion handling into a work structure,
which is handeled on the mac80211 workqueue. This simplifies
the code in rt2x00lib since it no longer needs to check if the
device is USB or PCI to decide which mac80211 function should be used.

In the watchdog some changes are needed since it can no longer rely
on the TX completion function to be run while looping through the
entries. (Both functions now work on the same workqueue, so this
would deadlock). So the watchdog now waits for the URB to return,
and handle the TX status report directly.

As a side-effect, the debugfs entry for the RX queue now correctly
displays the positions of the INDEX and INDEX_DONE counters. This
also implies that it is not possible to perform checks like queue_empty()
and queue_full() on the RX queue.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Implement watchdog monitoring for USB devices (PCI support can
be added later). This will determine if URBs being uploaded to
the hardware are actually returning. Both rt2500usb and rt2800usb
have shown that URBs being uploaded can remain hanging without
being released by the hardware.
By using this watchdog, a queue can be reset when this occurs.
For rt2800usb it has been tested that the connection is preserved
even though this interruption.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Now that the write_tx_data functions are merged, also merge the relevant
parts of the txdone handling into common code, rather than {usb,pci}
specific code.
Signed-off-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Now that rt2x00pci_write_tx_data and rt2x00usb_write_tx_data are similar
we can merge them in a single function in rt2x00queue.c.
Signed-off-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There is no need to fill the TX URB this early, and moving it to the
rt2x00usb_kick_tx_entry function allows us to merge the PCI and USB
variants of the write_tx_data function.
Signed-off-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We forgot to clear the SKBDESC_DESC_IN_SKB when the descriptor was removed
from the front of the skb.
Signed-off-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There is no need to force the separation between a buffer USB vendor
request that does fit the CSR cache and one that doesn't onto the
callers. This is something that the rt2x00usb_vendor_request_buff
function can figure out by itself.
Combine the rt2x00usb_vendor_request_buff and
rt2x00usb_vendor_request_large_buff functions into a single one, as
both of them were equivalent for small buffers anyway.
Signed-off-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>

Instead of fiddling with the skb->data pointer and thereby risking
out of bounds accesses, properly reserve the space needed in an
skb for descriptors.
Signed-off-by: NGertjan van Wingerde <gwingerde@gmail.com>
Acked-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>

For rt2800 reverse the calling order of rt2x00pci_write_data and
rt2800pci_write_data. Currently rt2800pci_write_data calls rt2x00pci_write_data
as there can be only 1 driver callback function specified by the driver.
Reverse this calling order by introducing a new driver callback function,
called write_tx_datadesc, which is called from the bus-specific write_tx_data
functions.
Preparation for futher cleanups in the skb data handling of rt2x00.
Signed-off-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>

The handling of tx descriptors for beacons can be simplified by updating
write_tx_desc implementations of each driver to write directly to the
queue entry descriptor instead of to a provided memory area.
This is also a preparation for further clean ups where descriptors are
properly reserved in the skb instead of fiddling with the skb data
pointer.
Signed-off-by: NGertjan van Wingerde <gwingerde@gmail.com>
Acked-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Extend the write_tx_data callback with a txdesc parameter to allow
access to the tx desciptor while preparing the tx data.
Signed-off-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Acked-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

As mentioned on the linux-wireless mailing list, the current copyright
statements in the rt2x00 are meaningless, as the rt2x00 project is
not even a formal legal entity. Therefore it is better to replace
the existing copyright statements with copyright statements for the
people that actually wrote the code.

Note: Updated to the best of my knowledge with respect to who
contributed considerable amounts of code.
Signed-off-by: NGertjan van Wingerde <gwingerde@gmail.com>
Acked-by: NIvo van Doorn <IvDoorn@gmail.com>
CC: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Make sure all drivers can benefit of the assignment of the interface
type of an adapter, instead of keeping it for rt2800 only.
Signed-off-by: NGertjan van Wingerde <gwingerde@gmail.com>
Acked-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add const to 'field' argument of rt2x00usb_regbusy_read()
(all arguments match rt2x00pci_regbusy_read() ones now).
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Acked-by: NIvo van Doorn <IvDoorn@gmail.com>
Acked-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This prevents the rt2x00 driver from queueing ieee80211 work after the  
USB card has been removed, preventing a kernel panic.
Signed-off-by: NSean Cross <sean@chumby.com>
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

After suspend & resume the rt2x00 devices won't wakeup
anymore due to a broken register information setup.
The most important problem is the release of the EEPROM
buffer which is completely cleared and never read again
after the suspend.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

provide rt2x00lib the possibility to kill a particular TX queue.
This can be useful when disabling the radio, but more importantly
will allow beaconing to be disabled when mac80211 requests this
(during scanning for example)
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The queue_end() macro points to 1 position after the
queue, which means that if we want to know if queue
is at the end of the queue we should first increment
the position and then check if it is a valid entry.

This fixes a segmentation fault which only occurs when
the device has enough endpoints to provide a dedicated
endpoint for all TX queues (which likely won't happen
for rt2500usb and rt73usb, but will happen for rt2800usb).
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Instead of hardcoding the used in/out endpoints
we should detect them by walking through all
available endpoints.

rt2800usb will gain the most out of this, because
the legacy drivers indicate that there are multiple
endpoints available.
However this code might benefit at least rt73usb as
well for the MIMO queues, and if we are really lucky
rt2500usb will benefit because for the TX and PRIO
queues.

Even if rt2500usb and rt73usb do not get better performance
after this patch, the endpoint detection still belongs to
rt2x00usb, and it shouldn't hurt to always try to detect
the available endpoints.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

rt2500usb and rt73usb have different register word sizes,
for that reason the register access wrappers were never
moved into rt2x00usb.
With rt2800usb on its way, we should favor the 32bit
register access and move those wrappers into rt2x00usb.
That saves duplicate code, since only rt2500usb will
need the special 16bit wrappers.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Indirect registers require multiple calls to the CSR
register in order to access the indirect registers.
This must be protected under a lock to prevent race
conditions which could cause invalid data to
be returned when reading from the indirect register or silent
failures when writing data to the indirect register.

USB drivers where already protected under a mutex,
so rename the mutex and make PCI drivers use the mutex
as well.
This now means that BBP and RF registers are no longer
accessible in interrupt context. That is not a bad
situation since the slow behavior of accessing
those registers means we don't _want_ to access them
in interrupt context either.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>