[PATCH rtw-next v4 0/2] wifi: rtw88: channel switch in AP mode

[Mehmet Fide <mehmet.fide@gmail.com>]

From: Mehmet Fide <mehmet.fide@screeningeagle.com>

An rtw88 AP cannot change its channel: the driver does not announce
channel switch support, so hostapd's CHAN_SWITCH is refused and the
only way is to tear the AP down. The series fixes the beacon download
the reserved page build makes twice, then implements
channel_switch_beacon on top of the firmware's beacon page.

v4:
- 1/2: Reviewed-by from Luka
- 2/2: the countdown work is back in the device, initialised once,
  with csa_vif naming the interface; no interface iteration and no
  lookup through the reserved page any more (Ping-Ke)
- 2/2: the countdown is cancelled before a firmware recovery restarts
  the hardware, instead of guarding the work with flags (Ping-Ke)
- 2/2: the page download on association skips a running countdown,
  like the TIM update and the PG backup (Luka)
- 2/2: the scan refusal comes before the scan offload test, so that
  firmware without scan offload does not fall back to a software scan
  during a countdown (Luka)
- tested on an RTL8821CU and an RTL8822CU as AP (counts 1 to 5,
  switches aborted and restarted, 50 switches with a station attached)
  and as IBSS

v3:
- 1/2: the beacon out-pointer is initialised in the caller (Luka)
- 2/2: the countdown work lives in the interface, remove_interface
  cancels it unconditionally, the queue wrapper and the comments are
  gone (Ping-Ke)
- 2/2: the TIM update and the PG backup on set_key skip the page
  download while a switch is announced; every beacon fetch advances
  the countdown (Luka)
- 2/2: the commit message names the refused hardware scan (Ping-Ke)
- the hardware scan path ran on an RTL8822CU, whose firmware has scan
  offload: a scan with the AP up keeps the beacon and the station, a
  scan during a countdown is refused

v2:
- 2/2: a hardware scan is refused while a switch is announced
- the rtw89 mention is gone from the cover

Mehmet Fide (2):
  wifi: rtw88: download the beacon the reserved page was built with
  wifi: rtw88: support channel switch in AP mode

 drivers/net/wireless/realtek/rtw88/fw.c       | 96 ++++++++++++++++---
 drivers/net/wireless/realtek/rtw88/fw.h       |  4 +
 drivers/net/wireless/realtek/rtw88/mac80211.c | 47 +++++++--
 drivers/net/wireless/realtek/rtw88/main.c     |  9 +-
 drivers/net/wireless/realtek/rtw88/main.h     |  2 +
 5 files changed, 136 insertions(+), 22 deletions(-)

-- 
2.55.0