linux-toradex.git/drivers/net/wireless/rt2x00/rt2x00dev.c, branch v3.0.53 Linux kernel for Apalis and Colibri modules rt2x00: fix random stalls 2012-03-19T15:57:44+00:00 Stanislaw Gruszka sgruszka@redhat.com 2012-03-09T11:39:54+00:00 60d3a450571b3d92f5f9f78f2898a7f425031b51 commit 3780d038fdf4b5ef26ead10b0604ab1f46dd9510 upstream. Is possible that we stop queue and then do not wake up it again, especially when packets are transmitted fast. That can be easily reproduced with modified tx queue entry_num to some small value e.g. 16. If mac80211 already hold local->queue_stop_reason_lock, then we can wait on that lock in both rt2x00queue_pause_queue() and rt2x00queue_unpause_queue(). After drooping ->queue_stop_reason_lock is possible that __ieee80211_wake_queue() will be performed before __ieee80211_stop_queue(), hence we stop queue and newer wake up it again. Another race condition is possible when between rt2x00queue_threshold() check and rt2x00queue_pause_queue() we will process all pending tx buffers on different cpu. This might happen if for example interrupt will be triggered on cpu performing rt2x00mac_tx(). To prevent race conditions serialize pause/unpause by queue->tx_lock. Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Acked-by: Gertjan van Wingerde <gwingerde@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3780d038fdf4b5ef26ead10b0604ab1f46dd9510 upstream.

Is possible that we stop queue and then do not wake up it again,
especially when packets are transmitted fast. That can be easily
reproduced with modified tx queue entry_num to some small value e.g. 16.

If mac80211 already hold local->queue_stop_reason_lock, then we can wait
on that lock in both rt2x00queue_pause_queue() and
rt2x00queue_unpause_queue(). After drooping ->queue_stop_reason_lock
is possible that __ieee80211_wake_queue() will be performed before
__ieee80211_stop_queue(), hence we stop queue and newer wake up it
again.

Another race condition is possible when between rt2x00queue_threshold()
check and rt2x00queue_pause_queue() we will process all pending tx
buffers on different cpu. This might happen if for example interrupt
will be triggered on cpu performing rt2x00mac_tx().

To prevent race conditions serialize pause/unpause by queue->tx_lock.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rt2x00: Fix sleep-while-atomic bug in powersaving code. 2011-11-26T17:09:54+00:00 Gertjan van Wingerde gwingerde@gmail.com 2011-11-12T18:10:44+00:00 11885cd854b27c1dcf35ab44d4899e8d20e08290 commit ed66ba472a742cd8df37d7072804b2111cdb1014 upstream. The generic powersaving code that determines after reception of a frame whether the device should go back to sleep or whether is could stay awake was calling rt2x00lib_config directly from RX tasklet context. On a number of the devices this call can actually sleep, due to having to confirm that the sleeping commands have been executed successfully. Fix this by moving the call to rt2x00lib_config to a workqueue call. This fixes bug https://bugzilla.redhat.com/show_bug.cgi?id=731672 Tested-by: Tomas Trnka <tomastrnka@gmx.com> Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com> Acked-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit ed66ba472a742cd8df37d7072804b2111cdb1014 upstream.

The generic powersaving code that determines after reception of a frame
whether the device should go back to sleep or whether is could stay
awake was calling rt2x00lib_config directly from RX tasklet context.
On a number of the devices this call can actually sleep, due to having
to confirm that the sleeping commands have been executed successfully.

Fix this by moving the call to rt2x00lib_config to a workqueue call.

This fixes bug https://bugzilla.redhat.com/show_bug.cgi?id=731672

Tested-by: Tomas Trnka <tomastrnka@gmx.com>
Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
rt2x00: fix rmmod crash 2011-06-06T19:24:18+00:00 Stanislaw Gruszka stf_xl@wp.pl 2011-06-04T14:48:54+00:00 3bb42a64960253353278876ca8da6b0a7d3bea87 Avoid queue and run autowakeup_work when device is not present anymore. That prevent rmmod and device remove crash introduced by: commit 1c0bcf89d85cc97a0d9ce4cd909351a81fa4fdde Author: Ivo van Doorn <ivdoorn@gmail.com> Date: Sat Apr 30 17:18:18 2011 +0200 rt2x00: Add autowake support for USB hardware Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl> Acked-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> 
Avoid queue and run autowakeup_work when device is not present anymore.
That prevent rmmod and device remove crash introduced by:

commit 1c0bcf89d85cc97a0d9ce4cd909351a81fa4fdde
Author: Ivo van Doorn <ivdoorn@gmail.com>
Date:   Sat Apr 30 17:18:18 2011 +0200

    rt2x00: Add autowake support for USB hardware

Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
rt2x00: Fix rmmod hang of rt2800pci 2011-05-10T19:54:48+00:00 Gertjan van Wingerde gwingerde@gmail.com 2011-05-07T15:27:46+00:00 9a24af1136e6d08c73010205caa282f46223aed5 txstatus_timer should only be deleted for USB devices, as it is only initialized for USB devices. Reported-by: Andreas Hartmann <andihartmann@01019freenet.de> Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com> Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> 
txstatus_timer should only be deleted for USB devices, as it is only
initialized for USB devices.

Reported-by: Andreas Hartmann <andihartmann@01019freenet.de>
Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
rt2x00: Add autowake support for USB hardware 2011-05-02T18:49:19+00:00 Ivo van Doorn ivdoorn@gmail.com 2011-04-30T15:18:18+00:00 1c0bcf89d85cc97a0d9ce4cd909351a81fa4fdde The USB drivers don't support automatically waking up when in powersaving mode, add a work object which will wakeup the device in time to receive the next beacon. Based on that beacon, we either go back into powersaving mode, or we remain awake to receive the buffered frames for our station. Some part of the code, especially rt2x00lib_find_ie and rt2x00lib_rxdone_check_ps are inspired on the code from carl9170. Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> 
The USB drivers don't support automatically waking up when in powersaving mode,
add a work object which will wakeup the device in time to receive the next beacon.
Based on that beacon, we either go back into powersaving mode, or we remain awake
to receive the buffered frames for our station.

Some part of the code, especially rt2x00lib_find_ie and rt2x00lib_rxdone_check_ps
are inspired on the code from carl9170.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
rt2800usb: add timer to handle TX_STA_FIFO 2011-04-19T19:39:35+00:00 Johannes Stezenbach js@sig21.net 2011-04-18T13:30:36+00:00 f0187a1987ed6524518ff2a533eaf8394ac1a500 TX status is reported by the hardware when a packet has been sent (or after TX failed after possible retries), which is some time after the DMA completion. Since the rt2800usb hardware can not signal interrupts we have to use a timer, otherwise the TX status would only be read by the next packet's TX DMA completion, or by the watchdog thread. Signed-off-by: Johannes Stezenbach <js@sig21.net> Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> 
TX status is reported by the hardware when a packet has been
sent (or after TX failed after possible retries), which is some
time after the DMA completion.  Since the rt2800usb hardware can
not signal interrupts we have to use a timer, otherwise the
TX status would only be read by the next packet's TX DMA
completion, or by the watchdog thread.

Signed-off-by: Johannes Stezenbach <js@sig21.net>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
rt2x00: fix queue timeout checks 2011-04-19T19:39:30+00:00 Johannes Stezenbach js@sig21.net 2011-04-18T13:29:38+00:00 75256f0348d38f414b7ac50ac78d4a4532bb6762 Add a timestamp to each queue entry which is updated whenever the status of the entry changes, and remove the per-queue timestamps. The previous check was incorrect and caused both false positives and false negatives. With the corrected check it comes apparent that the TX status usually times out on rt2800usb unless there is sufficient traffic (i.e. the next TX will complete the previous TX status). Signed-off-by: Johannes Stezenbach <js@sig21.net> Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> 
Add a timestamp to each queue entry which is updated whenever
the status of the entry changes, and remove the per-queue
timestamps.  The previous check was incorrect and caused both
false positives and false negatives.

With the corrected check it comes apparent that the TX status
usually times out on rt2800usb unless there is sufficient traffic
(i.e. the next TX will complete the previous TX status).

Signed-off-by: Johannes Stezenbach <js@sig21.net>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
rt2x00: Split rt2x00dev->flags 2011-04-19T19:39:11+00:00 Ivo van Doorn IvDoorn@gmail.com 2011-04-18T13:27:06+00:00 7dab73b37f5e8885cb73efd25e73861f9b4f0246 The number of flags defined for the rt2x00dev->flags field, has been growing over the years. Currently we are approaching the maximum number of bits which are available in the field. A secondary problem, is that one part of the field are initialized only during boot, because the driver requirements are initialized or device requirements are loaded from the EEPROM. In both cases, the flags are fixed and will not change during device operation. The other flags are the device state, and will change frequently. So far this resulted in the fact that for some flags, the atomic bit accessors are used, while for the others the non-atomic variants are used. By splitting the flags up into a "flags" and "cap_flags" we can put all flags which are fixed inside "cap_flags". This field can then be read non-atomically. In the "flags" field we keep the device state, which is going to be read atomically. This adds more room for more flags in the future, and sanitizes the field access methods. Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com> Acked-by: Helmut Schaa <helmut.schaa@googlemail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> 
The number of flags defined for the rt2x00dev->flags field,
has been growing over the years. Currently we are approaching
the maximum number of bits which are available in the field.

A secondary problem, is that one part of the field are initialized only
during boot, because the driver requirements are initialized or device
requirements are loaded from the EEPROM. In both cases, the flags are
fixed and will not change during device operation. The other flags are
the device state, and will change frequently. So far this resulted in the fact
that for some flags, the atomic bit accessors are used, while for the others
the non-atomic variants are used.

By splitting the flags up into a "flags" and "cap_flags" we can put all flags
which are fixed inside "cap_flags". This field can then be read non-atomically.
In the "flags" field we keep the device state, which is going to be read atomically.

This adds more room for more flags in the future, and sanitizes the field access methods.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Acked-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-2.6 2011-04-07T20:45:40+00:00 John W. Linville linville@tuxdriver.com 2011-04-07T20:45:40+00:00 b37e3b6d64358604960b35e8ecbb7aed22e0926e Conflicts: drivers/net/wireless/rtlwifi/efuse.c drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c net/bluetooth/mgmt.c 
Conflicts:
	drivers/net/wireless/rtlwifi/efuse.c
	drivers/net/wireless/rtlwifi/rtl8192c/fw_common.c
	net/bluetooth/mgmt.c
rt2x00: Fix tx aggregation problems with some clients 2011-04-04T20:20:04+00:00 Helmut Schaa helmut.schaa@googlemail.com 2011-03-28T11:35:21+00:00 f16d2db704b873d34cec54f992637f3579e10e08 Some clients seem to rely upon the reception of BlockAckReqs to flush their rx reorder buffer. In order to fix aggregation for these clients rt2x00 should send a BlockAckReq if the transmission of an AMPDU subframe fails. Introduce a new flag TXDONE_AMPDU to indicate that this is an AMPDU subframe and pass IEEE80211_TX_STAT_AMPDU_NO_BACK to mac80211 if an AMPDU subframe failed during transmission. This fixes aggregation problems with Intel 5100 Windows STAs (and maybe others as well). Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com> Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> 
Some clients seem to rely upon the reception of BlockAckReqs to flush
their rx reorder buffer. In order to fix aggregation for these clients
rt2x00 should send a BlockAckReq if the transmission of an AMPDU
subframe fails.

Introduce a new flag TXDONE_AMPDU to indicate that this is an AMPDU
subframe and pass IEEE80211_TX_STAT_AMPDU_NO_BACK to mac80211 if an
AMPDU subframe failed during transmission.

This fixes aggregation problems with Intel 5100 Windows STAs (and maybe
others as well).

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>