Implement a utility function to return the current TX power cap for

the given node.

This takes into account the per-node cap, the ic cap and the
per-channel regulatory caps.

This is designed to replace references to ni_txpower in various net80211
drivers - ni_txpower doesn't necessarily reflect the actual cap for
the given node (eg if the node has the default value of 50dBm (100) and
the administrator has manually configured a lower TX power.)

1 files changed, 22 insertions, 0 deletions

diff --git a/sys/net80211/ieee80211_var.h b/sys/net80211/ieee80211_var.h
index 2e8f58b..9593ffe 100644
--- a/sys/net80211/ieee80211_var.h
+++ b/sys/net80211/ieee80211_var.h
@@ -822,6 +822,28 @@ ieee80211_htchanflags(const struct ieee80211_channel *c)
 }
 
 /*
+ * Fetch the current TX power (cap) for the given node.
+ *
+ * This includes the node and ic/vap TX power limit as needed,
+ * but it doesn't take into account any per-rate limit.
+ */
+static __inline uint16_t
+ieee80211_get_node_txpower(struct ieee80211_node *ni)
+{
+	struct ieee80211com *ic = ni->ni_ic;
+	uint16_t txpower;
+
+	txpower = ni->ni_txpower;
+	txpower = MIN(txpower, ic->ic_txpowlimit);
+	if (ic->ic_curchan != NULL) {
+		txpower = MIN(txpower, 2 * ic->ic_curchan->ic_maxregpower);
+		txpower = MIN(txpower, ic->ic_curchan->ic_maxpower);
+	}
+
+	return (txpower);
+}
+
+/*
  * Debugging facilities compiled in when IEEE80211_DEBUG is defined.
  *
  * The intent is that any problem in the net80211 layer can be