Use TXOP_HTTXOP for beacons to stay in sync with the legacy drivers.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-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>

For STBC transmissions rt2x00 used the number of RxSTBC streams the
destination STA indicates in its HT capabilities as STBC value in
the TXWI.

However, the legacy drivers and our own comment in rt2800.h suggest
that the STBC field in the TXWI only allows a value of 0 or 1.
The values 2 and 3 are reserved (probably for future devices).

And indeed, STBC transmissions to STAs indicating more then 1
RxSTBC stream fail when the STBC field is set to something >1.

Fix this by only setting the STBC field to 1 when STBC should be
used.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-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>

ieee80211_get_tx_rate is not valid for HT rates. Hence, restructure the
TX desciptor creation to be aware of MCS rates. The generic TX desciptor
creation now cares about the rate_mode (CCK, OFDM, MCS, GF).

As a result, ieee80211_get_tx_rate gets only called for legacy rates.

Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
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>

HT and no-HT rt2x00 devices use a partly different TX descriptor.
Optimize the tx desciptor memory layout by putting the PLCP and HT
substructs into a union and introduce a new driver flag to decide which
TX desciptor format is used by the device.

This saves us the expensive PLCP calculation fOr HT devices and the HT
descriptor setup on no-HT devices.

Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
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>

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-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>

The tx desciptor already gets initialized to 0. Hence, there's no need
to explicitly assign 0 to mpdu_density here.

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>

In order to lower the impact of probe rates don't send a frame as AMPDU
if the rate control algorithm sets IEEE80211_TX_CTL_RATE_CTRL_PROBE.
Otherwise a whole aggregate would be send with a probe rate which might
lead to numerous retries.

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>

Make use of the IEEE80211_TX_RC_DUP_DATA flag to duplicate a
transmission with legacy rates to both 20Mhz channels if set.
Also update the related comment in rt2800.h to describe the
behavior of the BW_40 flag for legacy rates.

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>

Fix a check for dynamic SM PS mode in the STAs HT caps. Since a
value of 3 means "SM PS disabled" the previous check assumed in
that case that "dynamic SM PS" was enabled and as such prefixed
every MCS>7 frame with a unnecessary RTS/CTS exchange. Also,
the bit shift was done in the wrong direction.

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>

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>

In case of mcs rates txrate->idx contains the mcs index to be used for
transmission. Previously the mcs values dedicated for legacy rates where
used for mcs transmissions which resulted in the use of mcs 0 in a number
of cases (e.g. for all mcs rates >= 15 as rt2x00 does not register legacy
rates with indexes >= 15).

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>

Use the IEEE80211_TX_CTL_STBC flag to determine the
correct value to be used for the STBC field in the
TX descriptor

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>

Closer inspection of the legacy Ralink driver reveals that in case of HT40+
or HT40- we must adjust the frequency settings that we program to the device.
Implement the same adjustment in the rt2x00 code.

With this HT40 seems to work for all devices supported by rt2800pci and
rt2800usb.

Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>

rt2800 devices use a different enumeration to specify what IFS values should
be used on frame transmission compared to the other rt2x00 devices. Hence,
create a new enum called txop that contains the valid values.

Furthermore use the appropriate txop values as found in the ralink drivers:
- TXOP_BACKOFF for management frames
- TXOP_SIFS for subsequent fragments in a burst
- TXOP_HTTXOP for all data frames

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.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: Gertjan van Wingerde <gwingerde@gmail.com>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
CC: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Extend rt2x00lib capabilities to support 802.11n,
it still lacks aggregation support, but that can
be added in the future.

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