This patch fixes a regression introduced in
"ath9k: avoid the copy skb->cb on every RX'd skb"

With that change, the rx status in skb->cb was left uninitialized
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Jumbograms are frames put together linked together through
more than one descriptor. For example ath9k_htc will use this
to send from the target a large frame split up into 2 or more
segments. The driver then would be in charge of putting the
frame back together.

When jumbograms are constructed the rx_stats->rs_more will
bet set and rx_stats->rs_status will not have any valid content
as the actual status will only be avialable at the end of
the chained descriptors.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This is now deprecated and unused within mac80211, so time
to remove it as otherwise we'd be doing some unecessary
computations for nothing.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

ath9k and ath9k_htc share a lot of common hardware characteristics.
They only differ in that ath9k_htc works with a target CPU and ath9k
works directly with the hardware. ath9k_htc will do *some* things in
the firmware, but a lot of others on the host.

The common 802.11n hardware code is already shared through the ath9k_hw
module. Common helpers amongst all Atheros drivers can use the ath module,
this includes ath5k and ar9170 as users. But there is some common driver
specific helpers which are not exactly hardware code which ath9k and
ath9k_htc can share. We'll be using ath9k_common for this to avoid
bloating the ath module and the common 802.11n hardware module ath9k_hw.

We start by sharing skb pre and post processing in preparation for a hand
off to mac80211.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>