[PATCH wireless-next 02/18] wifi: nl80211: Define Seamless Mobility Domain (SMD) device capability

[Pooventhiran G]

From: Sidhanta Sahu <sidhanta.sahu@xxxxxxxxxxxxxxxx>

Per IEEE P802.11bn/D2.0, Aug 2026, subclause 37.16, an AP MLD can be
managed by a Seamless Mobility Domain Management Entity (SMD-ME) along
with partner AP MLDs to enable seamless transition of an associated
non-AP MLD from the current AP MLD to a target AP MLD. A non-AP MLD
advertising SMD supports association to an SMD-ME and SMD BSS
Transition between AP MLDs within an SMD.

Subclause 37.16.11 defines an optional capability for the current AP
MLD to forward buffered downlink (DL) data frames for the non-AP MLD to
the target AP MLD.

Userspace needs a way to be aware of the driver's SMD capabilities so that
it can enable SMD configuration and operation only on capable devices.

Define two extended feature flags
 - NL80211_EXT_FEATURE_SMD for SMD management and BSS Transition
   capability
 - NL80211_EXT_FEATURE_SMD_DL_PKT_FORWARDING for DL data forwarding
   capability

so that userspace can gate SMD setup and data forwarding configuration
on driver support.

Signed-off-by: Sidhanta Sahu <sidhanta.sahu@xxxxxxxxxxxxxxxx>
Signed-off-by: Pooventhiran G <pooventhiran.g@xxxxxxxxxxxxxxxx>
---
 include/uapi/linux/nl80211.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index d8fefefc11a9..d9ce185b0ef1 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -7114,6 +7114,15 @@ enum nl80211_feature_flags {
  * @NL80211_EXT_FEATURE_PROBE_AP: Driver supports probing the associated AP
  *	in STA mode using @NL80211_CMD_PROBE_PEER.
  *
+ * @NL80211_EXT_FEATURE_SMD: Driver supports Seamless Mobility Domain (SMD)
+ *	and is managed by an SMD-ME to support SMD BSS Transition in AP mode
+ *	and supports association to an SMD-ME and SMD BSS transition in
+ *	non-AP STA mode.
+ *
+ * @NL80211_EXT_FEATURE_SMD_DL_PKT_FORWARDING: Driver supports forwarding of
+ *	buffered downlink (DL) data packets in AP mode to the non-AP STA during
+ *	SMD BSS Transition.
+ *
  * @NUM_NL80211_EXT_FEATURES: number of extended features.
  * @MAX_NL80211_EXT_FEATURES: highest extended feature index.
  */
@@ -7196,6 +7205,8 @@ enum nl80211_ext_feature_index {
 	NL80211_EXT_FEATURE_ROC_ADDR_FILTER,
 	NL80211_EXT_FEATURE_SET_KEY_LTF_SEED,
 	NL80211_EXT_FEATURE_PROBE_AP,
+	NL80211_EXT_FEATURE_SMD,
+	NL80211_EXT_FEATURE_SMD_DL_PKT_FORWARDING,
 
 	/* add new features before the definition below */
 	NUM_NL80211_EXT_FEATURES,

-- 
2.34.1