On 24-12-15 13:19, Arend van Spriel wrote:

This patch series adds support for configuration of BSS selection done by
the driver and/or firmware. It allows user-space to pass selection criteria
with the NL80211_CMD_CONNECT using NL80211_ATTR_BSS_SELECT. When user-space
does provide this attribute and no explicit BSSID is provided it will pass
the BSS selection criteria to the driver if the driver supports it.

When multiple BSS-es are found belonging to the same ESS, ie. Infra-BSS with
same SSID, the criteria can be used to select a BSS. The criteria defined are:

1. select BSS in specific band regardless RSSI level.

Not really regardless, but band would take precedence. So if there are
two BSS-es in the specified band it will still select the one with
highest RSSI.

2. adjust RSSI level for BSS-es in specified band.

I defined the attribute as unsigned, but maybe there are scenarios that
justify a signed value here. People may prefer using 5G band as it is
usually more quiet and channels are further apart. However, range can be
limited so people may use a penalty on RSSI, ie. a negative value.

Gr. AvS

Open issue:
-----------
* NL80211_CMD_CONNECT support ATTR_MAC and ATTR_MAC_HINT. When ATTR_MAC is
  used BSS selection criteria are ignored. What about ATTR_MAC_HINT?

Arend van Spriel (2):
  nl80211: add extended feature for BSS selection support
  brcmfmac: add support for nl80211 BSS_SELECT feature

 drivers/net/wireless/brcm80211/brcmfmac/cfg80211.c | 47 ++++++++++++++++++++++
 drivers/net/wireless/brcm80211/brcmfmac/common.c   | 38 ++++++++++-------
 drivers/net/wireless/brcm80211/brcmfmac/core.h     |  1 +
 include/net/cfg80211.h                             | 17 ++++++++
 include/uapi/linux/nl80211.h                       | 35 ++++++++++++++++
 net/wireless/nl80211.c                             | 46 +++++++++++++++++++++
 6 files changed, 169 insertions(+), 15 deletions(-)