On 5/16/2022 1:39 AM, Maxime Bizon wrote:
A PHY supporting 160Mhz with a reduced number of NSS may not have any
note correct abbreviation is: MHz
and it is suggested to use a space to separate the value from the units
of the IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK bits set.
For exemple, the QCA9984 is 4x4, but can only do 2x2 VHT160 or
s/exemple/example/
80+80. The corresponding VHT capabilities should be:
- IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK == 0
- Extended NSS BW == 2
If we use that hardware in AP mode, and a 160Mhz 2x2 STA without NSS
restriction connects to it, then that STA will set
IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK to 1.
The usual logic of using bitwise-and with our own capabilities does
not work here, the current code clears the SUPP_CHAN_WIDTH bits and
resolve STA bandwidth to 80Mhz instead of 160Mhz, fix this.
Signed-off-by: Maxime Bizon <mbizon@xxxxxxxxxx>
---
net/mac80211/vht.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/net/mac80211/vht.c b/net/mac80211/vht.c
index e856f9092137..7ef93adc4f24 100644
--- a/net/mac80211/vht.c
+++ b/net/mac80211/vht.c
@@ -230,9 +230,11 @@ ieee80211_vht_cap_ie_to_sta_vht_cap(struct ieee80211_sub_if_data *sdata,
sizeof(struct ieee80211_vht_mcs_info));
/* copy EXT_NSS_BW Support value or remove the capability */
- if (ieee80211_hw_check(&sdata->local->hw, SUPPORTS_VHT_EXT_NSS_BW))
+ if (ieee80211_hw_check(&sdata->local->hw, SUPPORTS_VHT_EXT_NSS_BW)) {
+ vht_cap->cap |= cap_info &
+ IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
vht_cap->cap |= (cap_info & IEEE80211_VHT_CAP_EXT_NSS_BW_MASK);
- else
+ } else
per the coding style when you use braces on any leg of if/else, use them
on all legs
vht_cap->vht_mcs.tx_highest &=
~cpu_to_le16(IEEE80211_VHT_EXT_NSS_BW_CAPABLE);
