git: 37ea95328ca6 - main - net80211: document where to find the HT TX width action frame.

The branch main has been updated by adrian:

URL: https://cgit.FreeBSD.org/src/commit/?id=37ea95328ca65ffc7368e4d842c28cbd87777b7a

commit 37ea95328ca65ffc7368e4d842c28cbd87777b7a
Author:     Adrian Chadd <adrian@FreeBSD.org>
AuthorDate: 2025-05-01 04:08:40 +0000
Commit:     Adrian Chadd <adrian@FreeBSD.org>
CommitDate: 2025-05-03 15:38:04 +0000

    net80211: document where to find the HT TX width action frame.
    
    This came up when understanding the what ni_chw was doing.
    
    Differential Revision:  https://reviews.freebsd.org/D50095
    Reviewed by:    bz
---
 sys/net80211/ieee80211_ht.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/sys/net80211/ieee80211_ht.c b/sys/net80211/ieee80211_ht.c
index 08912dc8fca2..d4e84ce92531 100644
--- a/sys/net80211/ieee80211_ht.c
+++ b/sys/net80211/ieee80211_ht.c
@@ -2592,6 +2592,11 @@ ht_recv_action_ba_delba(struct ieee80211_node *ni,
 	return 0;
 }
 
+/*
+ * Handle the HT channel width action frame.
+ *
+ * 802.11-2020 9.6.11.2 (Notify Channel Width frame format).
+ */
 static int
 ht_recv_action_ht_txchwidth(struct ieee80211_node *ni,
 	const struct ieee80211_frame *wh __unused,
@@ -2603,6 +2608,11 @@ ht_recv_action_ht_txchwidth(struct ieee80211_node *ni,
 	if ((ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40) == 0)
 		return (0);
 
+	/*
+	 * The supported values are either 0 (any supported width)
+	 * or 1 (HT20).  80, 160, etc MHz widths are not represented
+	 * here.
+	 */
 	chw = (frm[2] == IEEE80211_A_HT_TXCHWIDTH_2040) ?
 	    IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;