diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2020-05-28 21:34:35 +0200 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2020-05-31 11:26:50 +0200 |
| commit | 2a333a0db24e37daa2e4eb9a542c07deda44ca5a (patch) | |
| tree | 9a7540d90e9ab588e4574b6acf78083a6efdc029 /net/mac80211/util.c | |
| parent | 607ca9ea3462719e256b60b24286f984e0d48c9b (diff) | |
mac80211: avoid using ext NSS high BW if not supported
If the AP advertises inconsistent data, namely it has CCFS1 or CCFS2,
but doesn't advertise support for 160/80+80 bandwidth or "Extended NSS
BW Support", then we cannot use any MCSes in the the higher bandwidth.
Thus, avoid connecting with higher bandwidth since it's less efficient
that way.
Link: https://lore.kernel.org/r/20200528213443.0e55d40c3ccc.I6fd0b4708ebd087e5e46466c3e91f6efbcbef668@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'net/mac80211/util.c')
| -rw-r--r-- | net/mac80211/util.c | 49 |
1 files changed, 45 insertions, 4 deletions
diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 87dd003dbdf2..e6104829fa1c 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -3120,7 +3120,7 @@ bool ieee80211_chandef_ht_oper(const struct ieee80211_ht_operation *ht_oper, return true; } -bool ieee80211_chandef_vht_oper(struct ieee80211_hw *hw, +bool ieee80211_chandef_vht_oper(struct ieee80211_hw *hw, u32 vht_cap_info, const struct ieee80211_vht_operation *oper, const struct ieee80211_ht_operation *htop, struct cfg80211_chan_def *chandef) @@ -3132,6 +3132,10 @@ bool ieee80211_chandef_vht_oper(struct ieee80211_hw *hw, u32 vht_cap; bool support_80_80 = false; bool support_160 = false; + u8 ext_nss_bw_supp = u32_get_bits(vht_cap_info, + IEEE80211_VHT_CAP_EXT_NSS_BW_MASK); + u8 supp_chwidth = u32_get_bits(vht_cap_info, + IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK); if (!oper || !htop) return false; @@ -3151,11 +3155,48 @@ bool ieee80211_chandef_vht_oper(struct ieee80211_hw *hw, IEEE80211_HT_OP_MODE_CCFS2_MASK) >> IEEE80211_HT_OP_MODE_CCFS2_SHIFT; - /* when parsing (and we know how to) CCFS1 and CCFS2 are equivalent */ ccf0 = ccfs0; - ccf1 = ccfs1; - if (!ccfs1 && ieee80211_hw_check(hw, SUPPORTS_VHT_EXT_NSS_BW)) + + /* if not supported, parse as though we didn't understand it */ + if (!ieee80211_hw_check(hw, SUPPORTS_VHT_EXT_NSS_BW)) + ext_nss_bw_supp = 0; + + /* + * Cf. IEEE 802.11 Table 9-250 + * + * We really just consider that because it's inefficient to connect + * at a higher bandwidth than we'll actually be able to use. + */ + switch ((supp_chwidth << 4) | ext_nss_bw_supp) { + default: + case 0x00: + ccf1 = 0; + support_160 = false; + support_80_80 = false; + break; + case 0x01: + support_80_80 = false; + /* fall through */ + case 0x02: + case 0x03: ccf1 = ccfs2; + break; + case 0x10: + ccf1 = ccfs1; + break; + case 0x11: + case 0x12: + if (!ccfs1) + ccf1 = ccfs2; + else + ccf1 = ccfs1; + break; + case 0x13: + case 0x20: + case 0x23: + ccf1 = ccfs1; + break; + } cf0 = ieee80211_channel_to_frequency(ccf0, chandef->chan->band); cf1 = ieee80211_channel_to_frequency(ccf1, chandef->chan->band); |