mac80211: add support for driver tx power reporting

The configured tx power is often limited by hardware capabilities,
channel settings, antenna configuration, etc.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[fix tracing compilation]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

4 files changed, 49 insertions, 0 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 1614b2fc3bf6..03edbf6f6230 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -2857,6 +2857,9 @@ enum ieee80211_roc_type {
  * @get_expected_throughput: extract the expected throughput towards the
  *      specified station. The returned value is expressed in Kbps. It returns 0
  *      if the RC algorithm does not have proper data to provide.
+ *
+ * @get_txpower: get current maximum tx power (in dBm) based on configuration
+ *      and hardware limits.
  */
 struct ieee80211_ops {
         void (*tx)(struct ieee80211_hw *hw,
@@ -3065,6 +3068,8 @@ struct ieee80211_ops {
         int (*join_ibss)(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
         void (*leave_ibss)(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
         u32 (*get_expected_throughput)(struct ieee80211_sta *sta);
+        int (*get_txpower)(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
+                           int *dbm);
 };
 
 /**
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index fbcc209687c8..b9659b8b70f8 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -2133,6 +2133,9 @@ static int ieee80211_get_tx_power(struct wiphy *wiphy,
         struct ieee80211_local *local = wiphy_priv(wiphy);
         struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
 
+        if (local->ops->get_txpower)
+                return drv_get_txpower(local, sdata, dbm);
+
         if (!local->use_chanctx)
                 *dbm = local->hw.conf.power_level;
         else
diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index 3df28e0fa045..d1e128e5db41 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -1279,4 +1279,18 @@ static inline u32 drv_get_expected_throughput(struct ieee80211_local *local,
         return ret;
 }
 
+static inline int drv_get_txpower(struct ieee80211_local *local,
+                                  struct ieee80211_sub_if_data *sdata, int *dbm)
+{
+        int ret;
+
+        if (!local->ops->get_txpower)
+                return -EOPNOTSUPP;
+
+        ret = local->ops->get_txpower(&local->hw, &sdata->vif, dbm);
+        trace_drv_get_txpower(local, sdata, *dbm, ret);
+
+        return ret;
+}
+
 #endif /* __MAC80211_DRIVER_OPS */
diff --git a/net/mac80211/trace.h b/net/mac80211/trace.h
index 976606aebac9..aeeace5ba47b 100644
--- a/net/mac80211/trace.h
+++ b/net/mac80211/trace.h
@@ -2150,6 +2150,33 @@ DEFINE_EVENT(local_sdata_evt, drv_post_channel_switch,
              TP_ARGS(local, sdata)
 );
 
+TRACE_EVENT(drv_get_txpower,
+        TP_PROTO(struct ieee80211_local *local,
+                 struct ieee80211_sub_if_data *sdata,
+                 int dbm, int ret),
+
+        TP_ARGS(local, sdata, dbm, ret),
+
+        TP_STRUCT__entry(
+                LOCAL_ENTRY
+                VIF_ENTRY
+                __field(int, dbm)
+                __field(int, ret)
+        ),
+
+        TP_fast_assign(
+                LOCAL_ASSIGN;
+                VIF_ASSIGN;
+                __entry->dbm = dbm;
+                __entry->ret = ret;
+        ),
+
+        TP_printk(
+                LOCAL_PR_FMT VIF_PR_FMT " dbm:%d ret:%d",
+                LOCAL_PR_ARG, VIF_PR_ARG, __entry->dbm, __entry->ret
+        )
+);
+
 
 #ifdef CONFIG_MAC80211_MESSAGE_TRACING
 #undef TRACE_SYSTEM