Re: [RFC 0/2] nl80211: allow configuration of BSS selection

[Arend van Spriel <aspriel@gmail.com>]

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(-)
>