[PATCH v2 mac80211-next 0/6] add offchannel radar chain support

[PATCH v2 mac80211-next 0/6] add offchannel radar chain support

[Lorenzo Bianconi]

Introduce the capability to configure a dedicated chain available for radar
detection on some hw (e.g. mt7915). This chain can't be used to transmit or
receive frames and it is bounded to a running wdev.
Offchannel radar/CAC detection allows to avoid the CAC downtime switching
to a different channel during CAC detection on the selected radar channel.
hostapd will implement the logic to select and configure the monitored
channel.

Changes since v1:
- introduce offchanel chain ownership through offchan_radar_wdev pointer
- spilt patch 1/5 in cfg80211 and mac80211 part
- move cac work from driver code to cfg80211

Changes since rfc:
- rely on NL80211_CMD_RADAR_DETECT netlink msg to configure offchannel radar
  chain

Lorenzo Bianconi (6):
  cfg80211: introduce set_radar_offchan callback
  mac80211: introduce set_radar_offchan callback
  cfg80211: introduce the capability to configure offchannel CAC
    detection
  cfg80211: introduce cfg80211_cac_offchan_event routine
  cfg80211: introduce offchannel cac delayed work
  cfg80211: introduce NL80211_EXT_FEATURE_RADAR_OFFCHAN feature flag

 include/net/cfg80211.h       |  24 +++++++
 include/net/mac80211.h       |  10 +++
 include/uapi/linux/nl80211.h |  13 ++++
 net/mac80211/cfg.c           |  13 ++++
 net/wireless/ap.c            |   2 +
 net/wireless/core.c          |   2 +
 net/wireless/core.h          |  15 +++++
 net/wireless/mlme.c          | 117 +++++++++++++++++++++++++++++++++++
 net/wireless/nl80211.c       |  17 +++--
 net/wireless/rdev-ops.h      |  18 ++++++
 net/wireless/trace.h         |  19 ++++++
 11 files changed, 244 insertions(+), 6 deletions(-)

-- 
2.31.1

[PATCH v2 mac80211-next 1/6] cfg80211: introduce set_radar_offchan callback

[Lorenzo Bianconi]

Introduce set_radar_offchan callback in cfg80211_ops in order to
configure a dedicated offchannel chain available for radar/CAC
detection on some hw. This chain can't be used to transmit
or receive frames and it is bounded to a running wdev.
Offchannel radar/CAC detection allows to avoid the CAC downtime
switching on a different channel during CAC detection on the selected
radar channel.

Tested-by: Evelyn Tsai <evelyn.tsai@mediatek.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 include/net/cfg80211.h  | 11 +++++++++++
 net/wireless/rdev-ops.h | 18 ++++++++++++++++++
 net/wireless/trace.h    | 19 +++++++++++++++++++
 3 files changed, 48 insertions(+)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 7c9d5db4f0e6..3bb76835f4b1 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -4072,6 +4072,15 @@ struct mgmt_frame_regs {
  * @set_fils_aad: Set FILS AAD data to the AP driver so that the driver can use
  *	those to decrypt (Re)Association Request and encrypt (Re)Association
  *	Response frame.
+ *
+ * @set_radar_offchan: Configure dedicated offchannel chain available for
+ *	radar/CAC detection on some hw. This chain can't be used to transmit
+ *	or receive frames and it is bounded to a running wdev.
+ *	Offchannel radar/CAC detection allows to avoid the CAC downtime
+ *	switching to a different channel during CAC detection on the selected
+ *	radar channel.
+ *	The caller is expected to set chandef pointer to NULL in order to
+ *	disable offchannel CAC/radar detection.
  */
 struct cfg80211_ops {
 	int	(*suspend)(struct wiphy *wiphy, struct cfg80211_wowlan *wow);
@@ -4404,6 +4413,8 @@ struct cfg80211_ops {
 				struct cfg80211_color_change_settings *params);
 	int     (*set_fils_aad)(struct wiphy *wiphy, struct net_device *dev,
 				struct cfg80211_fils_aad *fils_aad);
+	int	(*set_radar_offchan)(struct wiphy *wiphy,
+				     struct cfg80211_chan_def *chandef);
 };
 
 /*
diff --git a/net/wireless/rdev-ops.h b/net/wireless/rdev-ops.h
index cc1efec4b27b..980f1403e000 100644
--- a/net/wireless/rdev-ops.h
+++ b/net/wireless/rdev-ops.h
@@ -1395,4 +1395,22 @@ rdev_set_fils_aad(struct cfg80211_registered_device *rdev,
 	return ret;
 }
 
+static inline int
+rdev_set_radar_offchan(struct cfg80211_registered_device *rdev,
+		       struct cfg80211_chan_def *chandef)
+{
+	struct wiphy *wiphy = &rdev->wiphy;
+	int ret;
+
+	if (!rdev->ops->set_radar_offchan)
+		return -EOPNOTSUPP;
+
+	if (chandef)
+		trace_rdev_set_radar_offchan(wiphy, chandef);
+	ret = rdev->ops->set_radar_offchan(wiphy, chandef);
+	trace_rdev_return_int(wiphy, ret);
+
+	return ret;
+}
+
 #endif /* __CFG80211_RDEV_OPS */
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index ad6c16a06bcb..0b27eaa14a18 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -3674,6 +3674,25 @@ TRACE_EVENT(cfg80211_bss_color_notify,
 		  __entry->color_bitmap)
 );
 
+TRACE_EVENT(rdev_set_radar_offchan,
+	TP_PROTO(struct wiphy *wiphy, struct cfg80211_chan_def *chandef),
+
+	TP_ARGS(wiphy, chandef),
+
+	TP_STRUCT__entry(
+		WIPHY_ENTRY
+		CHAN_DEF_ENTRY
+	),
+
+	TP_fast_assign(
+		WIPHY_ASSIGN;
+		CHAN_DEF_ASSIGN(chandef)
+	),
+
+	TP_printk(WIPHY_PR_FMT ", " CHAN_DEF_PR_FMT,
+		  WIPHY_PR_ARG, CHAN_DEF_PR_ARG)
+);
+
 #endif /* !__RDEV_OPS_TRACE || TRACE_HEADER_MULTI_READ */
 
 #undef TRACE_INCLUDE_PATH
-- 
2.31.1

[PATCH v2 mac80211-next 2/6] mac80211: introduce set_radar_offchan callback

[Lorenzo Bianconi]

Similar to cfg80211, introduce set_radar_offchan callback in mac80211_ops
in order to configure a dedicated offchannel chain available on some hw
(e.g. mt7915) to perform offchannel CAC detection and avoid tx/rx downtime.

Tested-by: Evelyn Tsai <evelyn.tsai@mediatek.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 include/net/mac80211.h | 10 ++++++++++
 net/mac80211/cfg.c     | 13 +++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index dd757f0987b0..775dbb982654 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -3944,6 +3944,14 @@ struct ieee80211_prep_tx_info {
  *	twt structure.
  * @twt_teardown_request: Update the hw with TWT teardown request received
  *	from the peer.
+ * @set_radar_offchan: Configure dedicated offchannel chain available for
+ *	radar/CAC detection on some hw. This chain can't be used to transmit
+ *	or receive frames and it is bounded to a running wdev.
+ *	Offchannel radar/CAC detection allows to avoid the CAC downtime
+ *	switching to a different channel during CAC detection on the selected
+ *	radar channel.
+ *	The caller is expected to set chandef pointer to NULL in order to
+ *	disable offchannel CAC/radar detection.
  */
 struct ieee80211_ops {
 	void (*tx)(struct ieee80211_hw *hw,
@@ -4272,6 +4280,8 @@ struct ieee80211_ops {
 			      struct ieee80211_twt_setup *twt);
 	void (*twt_teardown_request)(struct ieee80211_hw *hw,
 				     struct ieee80211_sta *sta, u8 flowid);
+	int (*set_radar_offchan)(struct ieee80211_hw *hw,
+				 struct cfg80211_chan_def *chandef);
 };
 
 /**
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index e2b791c37591..1ab84830a38f 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -4379,6 +4379,18 @@ ieee80211_color_change(struct wiphy *wiphy, struct net_device *dev,
 	return err;
 }
 
+static int
+ieee80211_set_radar_offchan(struct wiphy *wiphy,
+			    struct cfg80211_chan_def *chandef)
+{
+	struct ieee80211_local *local = wiphy_priv(wiphy);
+
+	if (!local->ops->set_radar_offchan)
+		return -EOPNOTSUPP;
+
+	return local->ops->set_radar_offchan(&local->hw, chandef);
+}
+
 const struct cfg80211_ops mac80211_config_ops = {
 	.add_virtual_intf = ieee80211_add_iface,
 	.del_virtual_intf = ieee80211_del_iface,
@@ -4483,4 +4495,5 @@ const struct cfg80211_ops mac80211_config_ops = {
 	.reset_tid_config = ieee80211_reset_tid_config,
 	.set_sar_specs = ieee80211_set_sar_specs,
 	.color_change = ieee80211_color_change,
+	.set_radar_offchan = ieee80211_set_radar_offchan,
 };
-- 
2.31.1

[PATCH v2 mac80211-next 3/6] cfg80211: introduce the capability to configure offchannel CAC detection

[Lorenzo Bianconi]

Introduce NL80211_ATTR_RADAR_OFFCHAN netlink attribute in order to
configure a offchannel radar chain if supported by the underlay driver.
Since the offchannel chain is commonly shared between multiple wireless
devices, offchan_radar_wdev pointer refers to the current owner of the
chain. Offchannel can't be used by multiple wdev at the same time.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 include/uapi/linux/nl80211.h |  9 ++++++++
 net/wireless/ap.c            |  2 ++
 net/wireless/core.c          |  1 +
 net/wireless/core.h          | 11 ++++++++++
 net/wireless/mlme.c          | 40 ++++++++++++++++++++++++++++++++++++
 net/wireless/nl80211.c       | 17 +++++++++------
 6 files changed, 74 insertions(+), 6 deletions(-)

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 61cab81e920d..87ece3e68b8b 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2639,6 +2639,13 @@ enum nl80211_commands {
  *	Mandatory parameter for the transmitting interface to enable MBSSID.
  *	Optional for the non-transmitting interfaces.
  *
+ * @NL80211_ATTR_RADAR_OFFCHAN: Configure dedicated offchannel chain available for
+ *	radar/CAC detection on some hw. This chain can't be used to transmit
+ *	or receive frames and it is bounded to a running wdev.
+ *	Offchannel radar/CAC detection allows to avoid the CAC downtime
+ *	switching on a different channel during CAC detection on the selected
+ *	radar channel.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -3145,6 +3152,8 @@ enum nl80211_attrs {
 	NL80211_ATTR_MBSSID_CONFIG,
 	NL80211_ATTR_MBSSID_ELEMS,
 
+	NL80211_ATTR_RADAR_OFFCHAN,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
diff --git a/net/wireless/ap.c b/net/wireless/ap.c
index 550ac9d827fe..608fe3447158 100644
--- a/net/wireless/ap.c
+++ b/net/wireless/ap.c
@@ -25,6 +25,8 @@ int __cfg80211_stop_ap(struct cfg80211_registered_device *rdev,
 	if (!wdev->beacon_interval)
 		return -ENOENT;
 
+	cfg80211_stop_offchan_radar_detection(rdev);
+
 	err = rdev_stop_ap(rdev, dev);
 	if (!err) {
 		wdev->conn_owner_nlportid = 0;
diff --git a/net/wireless/core.c b/net/wireless/core.c
index 45be124a98f1..385c3654b385 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -498,6 +498,7 @@ struct wiphy *wiphy_new_nm(const struct cfg80211_ops *ops, int sizeof_priv,
 	}
 
 	mutex_init(&rdev->wiphy.mtx);
+	mutex_init(&rdev->offchan_mutex);
 	INIT_LIST_HEAD(&rdev->wiphy.wdev_list);
 	INIT_LIST_HEAD(&rdev->beacon_registrations);
 	spin_lock_init(&rdev->beacon_registrations_lock);
diff --git a/net/wireless/core.h b/net/wireless/core.h
index b35d0db12f1d..6e4d18fb93b1 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -84,6 +84,9 @@ struct cfg80211_registered_device {
 
 	struct delayed_work dfs_update_channels_wk;
 
+	struct mutex offchan_mutex; /* protect offchan_radar_wdev */
+	struct wireless_dev *offchan_radar_wdev;
+
 	/* netlink port which started critical protocol (0 means not started) */
 	u32 crit_proto_nlportid;
 
@@ -489,6 +492,14 @@ cfg80211_chandef_dfs_cac_time(struct wiphy *wiphy,
 
 void cfg80211_sched_dfs_chan_update(struct cfg80211_registered_device *rdev);
 
+int
+cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev,
+				       struct wireless_dev *wdev,
+				       struct cfg80211_chan_def *chandef);
+
+int
+cfg80211_stop_offchan_radar_detection(struct cfg80211_registered_device *rdev);
+
 bool cfg80211_any_wiphy_oper_chan(struct wiphy *wiphy,
 				  struct ieee80211_channel *chan);
 
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 3aa69b375a10..053293f51188 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -968,3 +968,43 @@ void cfg80211_cac_event(struct net_device *netdev,
 	nl80211_radar_notify(rdev, chandef, event, netdev, gfp);
 }
 EXPORT_SYMBOL(cfg80211_cac_event);
+
+int
+cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev,
+				       struct wireless_dev *wdev,
+				       struct cfg80211_chan_def *chandef)
+{
+	int err = -EBUSY;
+
+	mutex_lock(&rdev->offchan_mutex);
+	if (rdev->offchan_radar_wdev)
+		goto out;
+
+	err = rdev_set_radar_offchan(rdev, chandef);
+	if (err)
+		goto out;
+
+	rdev->offchan_radar_wdev = wdev;
+out:
+	mutex_unlock(&rdev->offchan_mutex);
+	return err;
+}
+
+int
+cfg80211_stop_offchan_radar_detection(struct cfg80211_registered_device *rdev)
+{
+	int err = 0;
+
+	mutex_lock(&rdev->offchan_mutex);
+	if (!rdev->offchan_radar_wdev)
+		goto out;
+
+	err = rdev_set_radar_offchan(rdev, NULL);
+	if (err)
+		goto out;
+
+	rdev->offchan_radar_wdev = NULL;
+out:
+	mutex_unlock(&rdev->offchan_mutex);
+	return err;
+}
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 81232b73df8f..25ee16558dfa 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -776,6 +776,7 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[NL80211_ATTR_MBSSID_CONFIG] =
 			NLA_POLICY_NESTED(nl80211_mbssid_config_policy),
 	[NL80211_ATTR_MBSSID_ELEMS] = { .type = NLA_NESTED },
+	[NL80211_ATTR_RADAR_OFFCHAN] = { .type = NLA_FLAG },
 };
 
 /* policy for the key attributes */
@@ -9280,12 +9281,6 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
 	if (err)
 		return err;
 
-	if (netif_carrier_ok(dev))
-		return -EBUSY;
-
-	if (wdev->cac_started)
-		return -EBUSY;
-
 	err = cfg80211_chandef_dfs_required(wiphy, &chandef, wdev->iftype);
 	if (err < 0)
 		return err;
@@ -9296,6 +9291,16 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
 	if (!cfg80211_chandef_dfs_usable(wiphy, &chandef))
 		return -EINVAL;
 
+	if (nla_get_flag(info->attrs[NL80211_ATTR_RADAR_OFFCHAN]))
+		return cfg80211_start_offchan_radar_detection(rdev, wdev,
+							      &chandef);
+
+	if (netif_carrier_ok(dev))
+		return -EBUSY;
+
+	if (wdev->cac_started)
+		return -EBUSY;
+
 	/* CAC start is offloaded to HW and can't be started manually */
 	if (wiphy_ext_feature_isset(wiphy, NL80211_EXT_FEATURE_DFS_OFFLOAD))
 		return -EOPNOTSUPP;
-- 
2.31.1

[PATCH v2 mac80211-next 4/6] cfg80211: introduce cfg80211_cac_offchan_event routine

[Lorenzo Bianconi]

Introduce cfg80211_cac_offchan_event routine in order to notify
userland when a Channel Availability Check (CAC) is finished, started
or aborted by a offchannel dedicated chain.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 include/net/cfg80211.h | 13 ++++++++++
 net/wireless/mlme.c    | 57 ++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 68 insertions(+), 2 deletions(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 3bb76835f4b1..8d075e11a1f8 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -7646,6 +7646,19 @@ void cfg80211_cac_event(struct net_device *netdev,
 			const struct cfg80211_chan_def *chandef,
 			enum nl80211_radar_event event, gfp_t gfp);
 
+/**
+ * cfg80211_offchan_cac_event - Channel Availability Check (CAC) offchan event
+ * @wiphy: the wiphy
+ * @chandef: chandef for the current channel
+ * @event: type of event
+ * @gfp: context flags
+ *
+ * This function is called when a Channel Availability Check (CAC) is finished,
+ * started or aborted by a offchannel dedicated chain.
+ */
+void cfg80211_offchan_cac_event(struct wiphy *wiphy,
+				const struct cfg80211_chan_def *chandef,
+				enum nl80211_radar_event event, gfp_t gfp);
 
 /**
  * cfg80211_gtk_rekey_notify - notify userspace about driver rekeying
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 053293f51188..9f379a91d7fd 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -969,6 +969,57 @@ void cfg80211_cac_event(struct net_device *netdev,
 }
 EXPORT_SYMBOL(cfg80211_cac_event);
 
+static void
+__cfg80211_offchan_cac_event(struct cfg80211_registered_device *rdev,
+			     struct wireless_dev *wdev,
+			     const struct cfg80211_chan_def *chandef,
+			     enum nl80211_radar_event event, gfp_t gfp)
+{
+	struct wiphy *wiphy = &rdev->wiphy;
+	struct net_device *netdev;
+
+	lockdep_assert_held(&rdev->offchan_mutex);
+
+	if (event != NL80211_RADAR_CAC_STARTED && !rdev->offchan_radar_wdev)
+		return;
+
+	switch (event) {
+	case NL80211_RADAR_CAC_FINISHED:
+		cfg80211_set_dfs_state(wiphy, chandef, NL80211_DFS_AVAILABLE);
+		memcpy(&rdev->cac_done_chandef, chandef, sizeof(*chandef));
+		queue_work(cfg80211_wq, &rdev->propagate_cac_done_wk);
+		cfg80211_sched_dfs_chan_update(rdev);
+		wdev = rdev->offchan_radar_wdev;
+		rdev->offchan_radar_wdev = NULL;
+		break;
+	case NL80211_RADAR_CAC_ABORTED:
+		wdev = rdev->offchan_radar_wdev;
+		rdev->offchan_radar_wdev = NULL;
+		break;
+	case NL80211_RADAR_CAC_STARTED:
+		WARN_ON(!wdev);
+		rdev->offchan_radar_wdev = wdev;
+		break;
+	default:
+		return;
+	}
+
+	netdev = wdev ? wdev->netdev : NULL;
+	nl80211_radar_notify(rdev, chandef, event, netdev, gfp);
+}
+
+void cfg80211_offchan_cac_event(struct wiphy *wiphy,
+				const struct cfg80211_chan_def *chandef,
+				enum nl80211_radar_event event, gfp_t gfp)
+{
+	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
+
+	mutex_lock(&rdev->offchan_mutex);
+	__cfg80211_offchan_cac_event(rdev, NULL, chandef, event, gfp);
+	mutex_unlock(&rdev->offchan_mutex);
+}
+EXPORT_SYMBOL(cfg80211_offchan_cac_event);
+
 int
 cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev,
 				       struct wireless_dev *wdev,
@@ -984,7 +1035,8 @@ cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev,
 	if (err)
 		goto out;
 
-	rdev->offchan_radar_wdev = wdev;
+	__cfg80211_offchan_cac_event(rdev, wdev, chandef,
+				     NL80211_RADAR_CAC_STARTED, GFP_KERNEL);
 out:
 	mutex_unlock(&rdev->offchan_mutex);
 	return err;
@@ -1003,7 +1055,8 @@ cfg80211_stop_offchan_radar_detection(struct cfg80211_registered_device *rdev)
 	if (err)
 		goto out;
 
-	rdev->offchan_radar_wdev = NULL;
+	__cfg80211_offchan_cac_event(rdev, NULL, NULL,
+				     NL80211_RADAR_CAC_ABORTED, GFP_KERNEL);
 out:
 	mutex_unlock(&rdev->offchan_mutex);
 	return err;
-- 
2.31.1

[PATCH v2 mac80211-next 5/6] cfg80211: introduce offchannel cac delayed work

[Lorenzo Bianconi]

Introduce cac delayed work in order to report NL80211_RADAR_CAC_FINISHED
to userspace.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 net/wireless/core.c |  1 +
 net/wireless/core.h |  4 ++++
 net/wireless/mlme.c | 20 ++++++++++++++++++++
 3 files changed, 25 insertions(+)

diff --git a/net/wireless/core.c b/net/wireless/core.c
index 385c3654b385..57e825bc37ea 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -545,6 +545,7 @@ struct wiphy *wiphy_new_nm(const struct cfg80211_ops *ops, int sizeof_priv,
 	INIT_WORK(&rdev->rfkill_block, cfg80211_rfkill_block_work);
 	INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
 	INIT_WORK(&rdev->event_work, cfg80211_event_work);
+	INIT_DELAYED_WORK(&rdev->offchan_cac_work, cfg80211_offchan_cac_work);
 
 	init_waitqueue_head(&rdev->dev_wait);
 
diff --git a/net/wireless/core.h b/net/wireless/core.h
index 6e4d18fb93b1..c129311834a0 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -86,6 +86,8 @@ struct cfg80211_registered_device {
 
 	struct mutex offchan_mutex; /* protect offchan_radar_wdev */
 	struct wireless_dev *offchan_radar_wdev;
+	struct cfg80211_chan_def offchan_radar_chandef;
+	struct delayed_work offchan_cac_work;
 
 	/* netlink port which started critical protocol (0 means not started) */
 	u32 crit_proto_nlportid;
@@ -500,6 +502,8 @@ cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev,
 int
 cfg80211_stop_offchan_radar_detection(struct cfg80211_registered_device *rdev);
 
+void cfg80211_offchan_cac_work(struct work_struct *work);
+
 bool cfg80211_any_wiphy_oper_chan(struct wiphy *wiphy,
 				  struct ieee80211_channel *chan);
 
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 9f379a91d7fd..532df85d1c26 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -969,6 +969,17 @@ void cfg80211_cac_event(struct net_device *netdev,
 }
 EXPORT_SYMBOL(cfg80211_cac_event);
 
+void cfg80211_offchan_cac_work(struct work_struct *work)
+{
+	struct delayed_work *delayed_work = to_delayed_work(work);
+	struct cfg80211_registered_device *rdev;
+
+	rdev = container_of(delayed_work, struct cfg80211_registered_device,
+			    offchan_cac_work);
+	cfg80211_offchan_cac_event(&rdev->wiphy, &rdev->offchan_radar_chandef,
+				   NL80211_RADAR_CAC_FINISHED, GFP_KERNEL);
+}
+
 static void
 __cfg80211_offchan_cac_event(struct cfg80211_registered_device *rdev,
 			     struct wireless_dev *wdev,
@@ -993,6 +1004,7 @@ __cfg80211_offchan_cac_event(struct cfg80211_registered_device *rdev,
 		rdev->offchan_radar_wdev = NULL;
 		break;
 	case NL80211_RADAR_CAC_ABORTED:
+		cancel_delayed_work(&rdev->offchan_cac_work);
 		wdev = rdev->offchan_radar_wdev;
 		rdev->offchan_radar_wdev = NULL;
 		break;
@@ -1025,6 +1037,7 @@ cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev,
 				       struct wireless_dev *wdev,
 				       struct cfg80211_chan_def *chandef)
 {
+	unsigned int cac_time_ms;
 	int err = -EBUSY;
 
 	mutex_lock(&rdev->offchan_mutex);
@@ -1035,8 +1048,15 @@ cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev,
 	if (err)
 		goto out;
 
+	cac_time_ms = cfg80211_chandef_dfs_cac_time(&rdev->wiphy, chandef);
+	if (!cac_time_ms)
+		cac_time_ms = IEEE80211_DFS_MIN_CAC_TIME_MS;
+
+	rdev->offchan_radar_chandef = *chandef;
 	__cfg80211_offchan_cac_event(rdev, wdev, chandef,
 				     NL80211_RADAR_CAC_STARTED, GFP_KERNEL);
+	queue_delayed_work(cfg80211_wq, &rdev->offchan_cac_work,
+			   msecs_to_jiffies(cac_time_ms));
 out:
 	mutex_unlock(&rdev->offchan_mutex);
 	return err;
-- 
2.31.1

[PATCH v2 mac80211-next 6/6] cfg80211: introduce NL80211_EXT_FEATURE_RADAR_OFFCHAN feature flag

[Lorenzo Bianconi]

Introduce NL80211_EXT_FEATURE_RADAR_OFFCHAN feature flag in order to
notify userland the underlay hw supports offchannel radar/CAC detection.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 include/uapi/linux/nl80211.h | 4 ++++
 net/wireless/mlme.c          | 4 ++++
 2 files changed, 8 insertions(+)

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 87ece3e68b8b..3e734826792f 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -6060,6 +6060,9 @@ enum nl80211_feature_flags {
  *	frames. Userspace has to share FILS AAD details to the driver by using
  *	@NL80211_CMD_SET_FILS_AAD.
  *
+ * @NL80211_EXT_FEATURE_RADAR_OFFCHAN: Device supports offchannel radar/CAC
+ *	detection.
+ *
  * @NUM_NL80211_EXT_FEATURES: number of extended features.
  * @MAX_NL80211_EXT_FEATURES: highest extended feature index.
  */
@@ -6126,6 +6129,7 @@ enum nl80211_ext_feature_index {
 	NL80211_EXT_FEATURE_PROT_RANGE_NEGO_AND_MEASURE,
 	NL80211_EXT_FEATURE_BSS_COLOR,
 	NL80211_EXT_FEATURE_FILS_CRYPTO_OFFLOAD,
+	NL80211_EXT_FEATURE_RADAR_OFFCHAN,
 
 	/* add new features before the definition below */
 	NUM_NL80211_EXT_FEATURES,
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 532df85d1c26..247ee0a01e8b 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -1040,6 +1040,10 @@ cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev,
 	unsigned int cac_time_ms;
 	int err = -EBUSY;
 
+	if (!wiphy_ext_feature_isset(&rdev->wiphy,
+				     NL80211_EXT_FEATURE_RADAR_OFFCHAN))
+		return -EOPNOTSUPP;
+
 	mutex_lock(&rdev->offchan_mutex);
 	if (rdev->offchan_radar_wdev)
 		goto out;
-- 
2.31.1