cfg80211: allow per interface TX power setting

The TX power setting is currently per wiphy (hardware
device) but with multi-channel capabilities that doesn't
make much sense any more.

Allow drivers (and mac80211) to advertise support for
per-interface TX power configuration. When the TX power
is configured for the wiphy, the wdev will be NULL and
the driver can still handle that, but when a wdev is
given the TX power can be set only for that wdev now.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

11 files changed, 56 insertions, 32 deletions

diff --git a/drivers/net/wireless/ath/ath6kl/cfg80211.c b/drivers/net/wireless/ath/ath6kl/cfg80211.c
index 277089963eb..d615f9f7506 100644
--- a/drivers/net/wireless/ath/ath6kl/cfg80211.c
+++ b/drivers/net/wireless/ath/ath6kl/cfg80211.c
@@ -1384,11 +1384,8 @@ static int ath6kl_cfg80211_set_wiphy_params(struct wiphy *wiphy, u32 changed)
         return 0;
 }
 
-/*
- * The type nl80211_tx_power_setting replaces the following
- * data type from 2.6.36 onwards
-*/
 static int ath6kl_cfg80211_set_txpower(struct wiphy *wiphy,
+                                       struct wireless_dev *wdev,
                                        enum nl80211_tx_power_setting type,
                                        int mbm)
 {
@@ -1423,7 +1420,9 @@ static int ath6kl_cfg80211_set_txpower(struct wiphy *wiphy,
         return 0;
 }
 
-static int ath6kl_cfg80211_get_txpower(struct wiphy *wiphy, int *dbm)
+static int ath6kl_cfg80211_get_txpower(struct wiphy *wiphy,
+                                       struct wireless_dev *wdev,
+                                       int *dbm)
 {
         struct ath6kl *ar = (struct ath6kl *)wiphy_priv(wiphy);
         struct ath6kl_vif *vif;
diff --git a/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c b/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
index cb30feaa565..904c94121c1 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
@@ -1721,7 +1721,7 @@ brcmf_cfg80211_disconnect(struct wiphy *wiphy, struct net_device *ndev,
 }
 
 static s32
-brcmf_cfg80211_set_tx_power(struct wiphy *wiphy,
+brcmf_cfg80211_set_tx_power(struct wiphy *wiphy, struct wireless_dev *wdev,
                             enum nl80211_tx_power_setting type, s32 mbm)
 {
 
@@ -1770,7 +1770,9 @@ done:
         return err;
 }
 
-static s32 brcmf_cfg80211_get_tx_power(struct wiphy *wiphy, s32 *dbm)
+static s32 brcmf_cfg80211_get_tx_power(struct wiphy *wiphy,
+                                       struct wireless_dev *wdev,
+                                       s32 *dbm)
 {
         struct brcmf_cfg80211_info *cfg = wiphy_to_cfg(wiphy);
         struct brcmf_if *ifp = netdev_priv(cfg_to_ndev(cfg));
diff --git a/drivers/net/wireless/mwifiex/cfg80211.c b/drivers/net/wireless/mwifiex/cfg80211.c
index fdb1eb86102..8e829b251d8 100644
--- a/drivers/net/wireless/mwifiex/cfg80211.c
+++ b/drivers/net/wireless/mwifiex/cfg80211.c
@@ -324,6 +324,7 @@ mwifiex_cfg80211_cancel_remain_on_channel(struct wiphy *wiphy,
  */
 static int
 mwifiex_cfg80211_set_tx_power(struct wiphy *wiphy,
+                              struct wireless_dev *wdev,
                               enum nl80211_tx_power_setting type,
                               int mbm)
 {
diff --git a/drivers/net/wireless/rndis_wlan.c b/drivers/net/wireless/rndis_wlan.c
index bd1f0cb5608..5390af36c06 100644
--- a/drivers/net/wireless/rndis_wlan.c
+++ b/drivers/net/wireless/rndis_wlan.c
@@ -490,9 +490,12 @@ static int rndis_scan(struct wiphy *wiphy,
 static int rndis_set_wiphy_params(struct wiphy *wiphy, u32 changed);
 
 static int rndis_set_tx_power(struct wiphy *wiphy,
+                              struct wireless_dev *wdev,
                               enum nl80211_tx_power_setting type,
                               int mbm);
-static int rndis_get_tx_power(struct wiphy *wiphy, int *dbm);
+static int rndis_get_tx_power(struct wiphy *wiphy,
+                              struct wireless_dev *wdev,
+                              int *dbm);
 
 static int rndis_connect(struct wiphy *wiphy, struct net_device *dev,
                                 struct cfg80211_connect_params *sme);
@@ -1903,6 +1906,7 @@ static int rndis_set_wiphy_params(struct wiphy *wiphy, u32 changed)
 }
 
 static int rndis_set_tx_power(struct wiphy *wiphy,
+                              struct wireless_dev *wdev,
                               enum nl80211_tx_power_setting type,
                               int mbm)
 {
@@ -1930,7 +1934,9 @@ static int rndis_set_tx_power(struct wiphy *wiphy,
         return -ENOTSUPP;
 }
 
-static int rndis_get_tx_power(struct wiphy *wiphy, int *dbm)
+static int rndis_get_tx_power(struct wiphy *wiphy,
+                              struct wireless_dev *wdev,
+                              int *dbm)
 {
         struct rndis_wlan_private *priv = wiphy_priv(wiphy);
         struct usbnet *usbdev = priv->usbdev;
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index c6964572890..8034a4268fc 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1551,7 +1551,10 @@ struct cfg80211_gtk_rekey_data {
  *      struct wiphy. If returning an error, no value should be changed.
  *
  * @set_tx_power: set the transmit power according to the parameters,
- *      the power passed is in mBm, to get dBm use MBM_TO_DBM().
+ *      the power passed is in mBm, to get dBm use MBM_TO_DBM(). The
+ *      wdev may be %NULL if power was set for the wiphy, and will
+ *      always be %NULL unless the driver supports per-vif TX power
+ *      (as advertised by the nl80211 feature flag.)
  * @get_tx_power: store the current TX power into the dbm variable;
  *      return 0 if successful
  *
@@ -1748,9 +1751,10 @@ struct cfg80211_ops {
 
         int     (*set_wiphy_params)(struct wiphy *wiphy, u32 changed);
 
-        int     (*set_tx_power)(struct wiphy *wiphy,
+        int     (*set_tx_power)(struct wiphy *wiphy, struct wireless_dev *wdev,
                                 enum nl80211_tx_power_setting type, int mbm);
-        int     (*get_tx_power)(struct wiphy *wiphy, int *dbm);
+        int     (*get_tx_power)(struct wiphy *wiphy, struct wireless_dev *wdev,
+                                int *dbm);
 
         int     (*set_wds_peer)(struct wiphy *wiphy, struct net_device *dev,
                                 const u8 *addr);
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 617d0fbfc96..4c5f6748ed7 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -3051,6 +3051,7 @@ enum nl80211_ap_sme_features {
  * @NL80211_FEATURE_LOW_PRIORITY_SCAN: This driver supports low priority scan
  * @NL80211_FEATURE_SCAN_FLUSH: Scan flush is supported
  * @NL80211_FEATURE_AP_SCAN: Support scanning using an AP vif
+ * @NL80211_FEATURE_VIF_TXPOWER: The driver supports per-vif TX power setting
  */
 enum nl80211_feature_flags {
         NL80211_FEATURE_SK_TX_STATUS                    = 1 << 0,
@@ -3062,6 +3063,7 @@ enum nl80211_feature_flags {
         NL80211_FEATURE_LOW_PRIORITY_SCAN               = 1 << 6,
         NL80211_FEATURE_SCAN_FLUSH                      = 1 << 7,
         NL80211_FEATURE_AP_SCAN                         = 1 << 8,
+        NL80211_FEATURE_VIF_TXPOWER                     = 1 << 9,
 };
 
 /**
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 34fd3eba309..a352e4d22dd 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1992,6 +1992,7 @@ static int ieee80211_set_wiphy_params(struct wiphy *wiphy, u32 changed)
 }
 
 static int ieee80211_set_tx_power(struct wiphy *wiphy,
+                                  struct wireless_dev *wdev,
                                   enum nl80211_tx_power_setting type, int mbm)
 {
         struct ieee80211_local *local = wiphy_priv(wiphy);
@@ -2026,7 +2027,9 @@ static int ieee80211_set_tx_power(struct wiphy *wiphy,
         return 0;
 }
 
-static int ieee80211_get_tx_power(struct wiphy *wiphy, int *dbm)
+static int ieee80211_get_tx_power(struct wiphy *wiphy,
+                                  struct wireless_dev *wdev,
+                                  int *dbm)
 {
         struct ieee80211_local *local = wiphy_priv(wiphy);
 
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 879ca620fd6..87d4670ee53 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -1585,9 +1585,13 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
         }
 
         if (info->attrs[NL80211_ATTR_WIPHY_TX_POWER_SETTING]) {
+                struct wireless_dev *txp_wdev = wdev;
                 enum nl80211_tx_power_setting type;
                 int idx, mbm = 0;
 
+                if (!(rdev->wiphy.features & NL80211_FEATURE_VIF_TXPOWER))
+                        txp_wdev = NULL;
+
                 if (!rdev->ops->set_tx_power) {
                         result = -EOPNOTSUPP;
                         goto bad_res;
@@ -1607,7 +1611,7 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
                         mbm = nla_get_u32(info->attrs[idx]);
                 }
 
-                result = rdev_set_tx_power(rdev, type, mbm);
+                result = rdev_set_tx_power(rdev, txp_wdev, type, mbm);
                 if (result)
                         goto bad_res;
         }
diff --git a/net/wireless/rdev-ops.h b/net/wireless/rdev-ops.h
index eb5f8974e14..6e5fa659068 100644
--- a/net/wireless/rdev-ops.h
+++ b/net/wireless/rdev-ops.h
@@ -476,21 +476,22 @@ rdev_set_wiphy_params(struct cfg80211_registered_device *rdev, u32 changed)
 }
 
 static inline int rdev_set_tx_power(struct cfg80211_registered_device *rdev,
+                                    struct wireless_dev *wdev,
                                     enum nl80211_tx_power_setting type, int mbm)
 {
         int ret;
-        trace_rdev_set_tx_power(&rdev->wiphy, type, mbm);
-        ret = rdev->ops->set_tx_power(&rdev->wiphy, type, mbm);
+        trace_rdev_set_tx_power(&rdev->wiphy, wdev, type, mbm);
+        ret = rdev->ops->set_tx_power(&rdev->wiphy, wdev, type, mbm);
         trace_rdev_return_int(&rdev->wiphy, ret);
         return ret;
 }
 
 static inline int rdev_get_tx_power(struct cfg80211_registered_device *rdev,
-                                    int *dbm)
+                                    struct wireless_dev *wdev, int *dbm)
 {
         int ret;
-        trace_rdev_get_tx_power(&rdev->wiphy);
-        ret = rdev->ops->get_tx_power(&rdev->wiphy, dbm);
+        trace_rdev_get_tx_power(&rdev->wiphy, wdev);
+        ret = rdev->ops->get_tx_power(&rdev->wiphy, wdev, dbm);
         trace_rdev_return_int_int(&rdev->wiphy, ret, *dbm);
         return ret;
 }
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index 0ca71caf85f..8e03c6382a8 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -26,7 +26,7 @@
 #define WIPHY_PR_ARG MAC_PR_ARG(wiphy_mac)
 
 #define WDEV_ENTRY __field(u32, id)
-#define WDEV_ASSIGN (__entry->id) = (wdev->identifier)
+#define WDEV_ASSIGN (__entry->id) = (wdev ? wdev->identifier : 0)
 #define WDEV_PR_FMT ", wdev id: %u"
 #define WDEV_PR_ARG (__entry->id)
 
@@ -260,11 +260,6 @@ DEFINE_EVENT(wiphy_only_evt, rdev_get_antenna,
         TP_ARGS(wiphy)
 );
 
-DEFINE_EVENT(wiphy_only_evt, rdev_get_tx_power,
-        TP_PROTO(struct wiphy *wiphy),
-        TP_ARGS(wiphy)
-);
-
 DEFINE_EVENT(wiphy_only_evt, rdev_rfkill_poll,
         TP_PROTO(struct wiphy *wiphy),
         TP_ARGS(wiphy)
@@ -1230,22 +1225,29 @@ TRACE_EVENT(rdev_set_wiphy_params,
                   WIPHY_PR_ARG, __entry->changed)
 );
 
+DEFINE_EVENT(wiphy_wdev_evt, rdev_get_tx_power,
+        TP_PROTO(struct wiphy *wiphy, struct wireless_dev *wdev),
+        TP_ARGS(wiphy, wdev)
+);
+
 TRACE_EVENT(rdev_set_tx_power,
-        TP_PROTO(struct wiphy *wiphy, enum nl80211_tx_power_setting type,
-                 int mbm),
-        TP_ARGS(wiphy, type, mbm),
+        TP_PROTO(struct wiphy *wiphy, struct wireless_dev *wdev,
+                 enum nl80211_tx_power_setting type, int mbm),
+        TP_ARGS(wiphy, wdev, type, mbm),
         TP_STRUCT__entry(
                 WIPHY_ENTRY
+                WDEV_ENTRY
                 __field(enum nl80211_tx_power_setting, type)
                 __field(int, mbm)
         ),
         TP_fast_assign(
                 WIPHY_ASSIGN;
+                WDEV_ASSIGN;
                 __entry->type = type;
                 __entry->mbm = mbm;
         ),
-        TP_printk(WIPHY_PR_FMT ", type: %d, mbm: %d",
-                  WIPHY_PR_ARG, __entry->type, __entry->mbm)
+        TP_printk(WIPHY_PR_FMT WDEV_PR_FMT ", type: %d, mbm: %d",
+                  WIPHY_PR_ARG, WDEV_PR_ARG,__entry->type, __entry->mbm)
 );
 
 TRACE_EVENT(rdev_return_int_int,
diff --git a/net/wireless/wext-compat.c b/net/wireless/wext-compat.c
index 6488d2dbc1d..742ab6ec4c9 100644
--- a/net/wireless/wext-compat.c
+++ b/net/wireless/wext-compat.c
@@ -895,7 +895,7 @@ static int cfg80211_wext_siwtxpower(struct net_device *dev,
                 return 0;
         }
 
-        return rdev_set_tx_power(rdev, type, DBM_TO_MBM(dbm));
+        return rdev_set_tx_power(rdev, wdev, type, DBM_TO_MBM(dbm));
 }
 
 static int cfg80211_wext_giwtxpower(struct net_device *dev,
@@ -914,7 +914,7 @@ static int cfg80211_wext_giwtxpower(struct net_device *dev,
         if (!rdev->ops->get_tx_power)
                 return -EOPNOTSUPP;
 
-        err = rdev_get_tx_power(rdev, &val);
+        err = rdev_get_tx_power(rdev, wdev, &val);
         if (err)
                 return err;