[PATCH 1/2] nl80211: add support to enable/disable bss color collision detection

[Rameshkumar Sundaram <quic_ramess@quicinc.com>]

As per 802.11ax-2021, STAs shall process BSS Color Change Announcement
(BCCA) from AP and switch to new color, but some STAs aren't processing
BCCA from AP and not doing color switch, causing them to drop data
frames from AP post color change.

Provide an option to disable color collision detection and therefore
not to do BCCA to mitigate the same from AP. If it's required in case
where STA supports BCCA handling, then it can enabled in AP using this
option.

Signed-off-by: Rameshkumar Sundaram <quic_ramess@quicinc.com>
---
 include/net/cfg80211.h       | 2 ++
 include/uapi/linux/nl80211.h | 3 +++
 net/mac80211/rx.c            | 3 ++-
 net/wireless/nl80211.c       | 3 +++
 4 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 03d4f4deadae..153a05a25d91 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -304,11 +304,13 @@ struct ieee80211_he_obss_pd {
  * @color: the current color.
  * @enabled: HE BSS color is used
  * @partial: define the AID equation.
+ * @collision_detection_enabled: HE BSS color collision detection is enabled.
  */
 struct cfg80211_he_bss_color {
 	u8 color;
 	bool enabled;
 	bool partial;
+	bool collision_detection_enabled;
 };
 
 /**
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index c14a91bbca7c..ec514669d203 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -7440,6 +7440,8 @@ enum nl80211_obss_pd_attributes {
  * @NL80211_HE_BSS_COLOR_ATTR_COLOR: the current BSS Color.
  * @NL80211_HE_BSS_COLOR_ATTR_DISABLED: is BSS coloring disabled.
  * @NL80211_HE_BSS_COLOR_ATTR_PARTIAL: the AID equation to be used..
+ * @NL80211_HE_BSS_COLOR_ATTR_COLLISION_DETECTION_DISABLED: is BSS
+ * color collision detection disabled.
  *
  * @__NL80211_HE_BSS_COLOR_ATTR_LAST: Internal
  * @NL80211_HE_BSS_COLOR_ATTR_MAX: highest BSS Color attribute.
@@ -7450,6 +7452,7 @@ enum nl80211_bss_color_attributes {
 	NL80211_HE_BSS_COLOR_ATTR_COLOR,
 	NL80211_HE_BSS_COLOR_ATTR_DISABLED,
 	NL80211_HE_BSS_COLOR_ATTR_PARTIAL,
+	NL80211_HE_BSS_COLOR_ATTR_COLLISION_DETECTION_DISABLED,
 
 	/* keep last */
 	__NL80211_HE_BSS_COLOR_ATTR_LAST,
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 7e3ab6e1b28f..382f467f0e31 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -3195,7 +3195,8 @@ ieee80211_rx_check_bss_color_collision(struct ieee80211_rx_data *rx)
 	if (ieee80211_hw_check(&rx->local->hw, DETECTS_COLOR_COLLISION))
 		return;
 
-	if (rx->sdata->vif.bss_conf.csa_active)
+	if (rx->sdata->vif.bss_conf.csa_active ||
+	    !rx->sdata->vif.bss_conf.he_bss_color.collision_detection_enabled)
 		return;
 
 	baselen = mgmt->u.beacon.variable - rx->skb->data;
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 33a82ecab9d5..8db437995e53 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -377,6 +377,7 @@ he_bss_color_policy[NL80211_HE_BSS_COLOR_ATTR_MAX + 1] = {
 	[NL80211_HE_BSS_COLOR_ATTR_COLOR] = NLA_POLICY_RANGE(NLA_U8, 1, 63),
 	[NL80211_HE_BSS_COLOR_ATTR_DISABLED] = { .type = NLA_FLAG },
 	[NL80211_HE_BSS_COLOR_ATTR_PARTIAL] = { .type = NLA_FLAG },
+	[NL80211_HE_BSS_COLOR_ATTR_COLLISION_DETECTION_DISABLED] = { .type = NLA_FLAG },
 };
 
 static const struct nla_policy nl80211_txattr_policy[NL80211_TXRATE_MAX + 1] = {
@@ -5414,6 +5415,8 @@ static int nl80211_parse_he_bss_color(struct nlattr *attrs,
 		!nla_get_flag(tb[NL80211_HE_BSS_COLOR_ATTR_DISABLED]);
 	he_bss_color->partial =
 		nla_get_flag(tb[NL80211_HE_BSS_COLOR_ATTR_PARTIAL]);
+	he_bss_color->collision_detection_enabled =
+		!nla_get_flag(tb[NL80211_HE_BSS_COLOR_ATTR_COLLISION_DETECTION_DISABLED]);
 
 	return 0;
 }

base-commit: 44bacbdf9066c590423259dbd6d520baac99c1a8
-- 
2.17.1