cfg80211: regulatory introduce maximum bandwidth calculation

In case we will get regulatory request with rule
where max_bandwidth_khz is set to 0 handle this
case as a special one.

If max_bandwidth_khz == 0 we should calculate maximum
available bandwidth base on all frequency contiguous rules.
In case we need auto calculation we just have to set:

country PL: DFS-ETSI
        (2402 - 2482 @ 40), (N/A, 20)
        (5170 - 5250 @ AUTO), (N/A, 20)
        (5250 - 5330 @ AUTO), (N/A, 20), DFS
        (5490 - 5710 @ 80), (N/A, 27), DFS

This mean we will calculate maximum bw for rules where
AUTO (N/A) were set, 160MHz (5330 - 5170) in example above.
So we will get:
        (5170 - 5250 @ 160), (N/A, 20)
        (5250 - 5330 @ 160), (N/A, 20), DFS

In other case:
country FR: DFS-ETSI
        (2402 - 2482 @ 40), (N/A, 20)
        (5170 - 5250 @ AUTO), (N/A, 20)
        (5250 - 5330 @ 80), (N/A, 20), DFS
        (5490 - 5710 @ 80), (N/A, 27), DFS

We will get 80MHz (5250 - 5170):
        (5170 - 5250 @ 80), (N/A, 20)
        (5250 - 5330 @ 80), (N/A, 20), DFS

Base on this calculations we will set correct channel
bandwidth flags (eg. IEEE80211_CHAN_NO_80MHZ).

We don't need any changes in CRDA or internal regulatory.

Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
[extend nl80211 description a bit, fix typo]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Janusz Dziedzic 2014-01-30 09:52:20 +01:00 committed by Johannes Berg
commit 9752482083
4 changed files with 130 additions and 22 deletions

View file

@ -2437,7 +2437,10 @@ enum nl80211_reg_type {
* in KHz. This is not a center a frequency but an actual regulatory
* band edge.
* @NL80211_ATTR_FREQ_RANGE_MAX_BW: maximum allowed bandwidth for this
* frequency range, in KHz.
* frequency range, in KHz. If not present or 0, maximum available
* bandwidth should be calculated base on contiguous rules and wider
* channels will be allowed to cross multiple contiguous/overlapping
* frequency ranges.
* @NL80211_ATTR_POWER_RULE_MAX_ANT_GAIN: the maximum allowed antenna gain
* for a given frequency range. The value is in mBi (100 * dBi).
* If you don't have one then don't send this.