[PATCH v3] ath10k: add support for controlling tx power to a station

[Ashok Raj Nagarajan]

This patch will add the support to control the transmit power for traffic
to a station associated with the AP. Userspace provide the transmit power
value in mBm units. ath10k firmware expects the value to be in dBm and
hence will convert the value from to dBm before passing down to firmware.

Underlying FW will enforce that the maximum tx power will be based on the
regulatory requirements. If the user given transmit power is greater than
the allowed tx power in the given channel, then the FW will use the maximum
tx power in the same channel.

When 0 is sent to the FW as tx power, it will revert to the automatic tx
power for the station.

Signed-off-by: Ashok Raj Nagarajan <arnagara at qti.qualcomm.com>
---
v3:
	- reword commit log
	- remove range check for the input from user. (Ben Greear)

 drivers/net/wireless/ath/ath10k/mac.c | 31 +++++++++++++++++++++++++++++++
 drivers/net/wireless/ath/ath10k/wmi.h |  1 +
 2 files changed, 32 insertions(+)

diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index 9977829..3b91468 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -5985,6 +5985,32 @@ static int ath10k_mac_tdls_vifs_count(struct ieee80211_hw *hw)
 	return num_tdls_vifs;
 }
 
+static int ath10k_sta_set_txpwr(struct ieee80211_hw *hw,
+				struct ieee80211_vif *vif,
+				struct ieee80211_sta *sta)
+{
+	struct ath10k *ar = hw->priv;
+	struct ath10k_vif *arvif = ath10k_vif_to_arvif(vif);
+	int ret = 0;
+	u16 txpwr;
+
+	txpwr = MBM_TO_DBM(sta->txpwr);
+
+	mutex_lock(&ar->conf_mutex);
+
+	ret = ath10k_wmi_peer_set_param(ar, arvif->vdev_id, sta->addr,
+					WMI_PEER_USE_FIXED_PWR, txpwr);
+	if (ret) {
+		ath10k_warn(ar, "failed to set tx power for station ret: %d\n",
+			    ret);
+		goto out;
+	}
+
+out:
+	mutex_unlock(&ar->conf_mutex);
+	return ret;
+}
+
 static int ath10k_sta_state(struct ieee80211_hw *hw,
 			    struct ieee80211_vif *vif,
 			    struct ieee80211_sta *sta,
@@ -7550,6 +7576,7 @@ static void ath10k_mac_op_sta_pre_rcu_remove(struct ieee80211_hw *hw,
 	.set_key			= ath10k_set_key,
 	.set_default_unicast_key        = ath10k_set_default_unicast_key,
 	.sta_state			= ath10k_sta_state,
+	.sta_set_txpwr			= ath10k_sta_set_txpwr,
 	.conf_tx			= ath10k_conf_tx,
 	.remain_on_channel		= ath10k_remain_on_channel,
 	.cancel_remain_on_channel	= ath10k_cancel_remain_on_channel,
@@ -8193,11 +8220,15 @@ int ath10k_mac_register(struct ath10k *ar)
 		ar->hw->wiphy->iface_combinations = ath10k_10x_if_comb;
 		ar->hw->wiphy->n_iface_combinations =
 			ARRAY_SIZE(ath10k_10x_if_comb);
+		wiphy_ext_feature_set(ar->hw->wiphy,
+				      NL80211_EXT_FEATURE_STA_TX_PWR);
 		break;
 	case ATH10K_FW_WMI_OP_VERSION_10_4:
 		ar->hw->wiphy->iface_combinations = ath10k_10_4_if_comb;
 		ar->hw->wiphy->n_iface_combinations =
 			ARRAY_SIZE(ath10k_10_4_if_comb);
+		wiphy_ext_feature_set(ar->hw->wiphy,
+				      NL80211_EXT_FEATURE_STA_TX_PWR);
 		break;
 	case ATH10K_FW_WMI_OP_VERSION_UNSET:
 	case ATH10K_FW_WMI_OP_VERSION_MAX:
diff --git a/drivers/net/wireless/ath/ath10k/wmi.h b/drivers/net/wireless/ath/ath10k/wmi.h
index 861c2d8..1ccb6bf 100644
--- a/drivers/net/wireless/ath/ath10k/wmi.h
+++ b/drivers/net/wireless/ath/ath10k/wmi.h
@@ -5811,6 +5811,7 @@ enum wmi_peer_param {
 	WMI_PEER_CHAN_WIDTH = 0x4,
 	WMI_PEER_NSS        = 0x5,
 	WMI_PEER_USE_4ADDR  = 0x6,
+	WMI_PEER_USE_FIXED_PWR = 0x8,
 	WMI_PEER_DUMMY_VAR  = 0xff, /* dummy parameter for STA PS workaround */
 };
 
-- 
1.9.1