rsi: Add support for configuring tx power

TX power can be configured from iwconfig, iw or from mac80211 when
regulatory changes are done. Hence support for configuring tx power
to device is added using the RADIO_PARAMS_UPDATE command frame.

Signed-off-by: Prameela Rani Garnepudi <[e-mail]>
Signed-off-by: Kalle Valo <[e-mail]>

drivers/net/wireless/rsi/rsi_91x_mac80211.c

···
 }
 
 /**
+ * rsi_config_power() - This function configures tx power to device
+ * @hw: Pointer to the ieee80211_hw structure.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+static int rsi_config_power(struct ieee80211_hw *hw)
+{
+	struct rsi_hw *adapter = hw->priv;
+	struct rsi_common *common = adapter->priv;
+	struct ieee80211_conf *conf = &hw->conf;
+
+	if (adapter->sc_nvifs <= 0) {
+		rsi_dbg(ERR_ZONE, "%s: No virtual interface found\n", __func__);
+		return -EINVAL;
+	}
+
+	rsi_dbg(INFO_ZONE,
+		"%s: Set tx power: %d dBM\n", __func__, conf->power_level);
+
+	if (conf->power_level == common->tx_power)
+		return 0;
+
+	common->tx_power = conf->power_level;
+
+	return rsi_send_radio_params_update(common);
+}
+
+/**
  * rsi_mac80211_config() - This function is a handler for configuration
  *			   requests. The stack calls this function to
  *			   change hardware configuration, e.g., channel.
···
 
 	if (changed & IEEE80211_CONF_CHANGE_CHANNEL)
 		status = rsi_channel_change(hw);
+
+	/* tx power */
+	if (changed & IEEE80211_CONF_CHANGE_POWER) {
+		rsi_dbg(INFO_ZONE, "%s: Configuring Power\n", __func__);
+		status = rsi_config_power(hw);
+	}
 
 	mutex_unlock(&common->mutex);
 

drivers/net/wireless/rsi/rsi_91x_mgmt.c

···
 }
 
 /**
+ * rsi_send_radio_params_update() - This function sends the radio
+ *				parameters update to device
+ * @common: Pointer to the driver private structure.
+ * @channel: Channel value to be set.
+ *
+ * Return: 0 on success, corresponding error code on failure.
+ */
+int rsi_send_radio_params_update(struct rsi_common *common)
+{
+	struct rsi_mac_frame *cmd_frame;
+	struct sk_buff *skb = NULL;
+
+	rsi_dbg(MGMT_TX_ZONE,
+		"%s: Sending Radio Params update frame\n", __func__);
+
+	skb = dev_alloc_skb(FRAME_DESC_SZ);
+	if (!skb) {
+		rsi_dbg(ERR_ZONE, "%s: Failed in allocation of skb\n",
+			__func__);
+		return -ENOMEM;
+	}
+
+	memset(skb->data, 0, FRAME_DESC_SZ);
+	cmd_frame = (struct rsi_mac_frame *)skb->data;
+
+	cmd_frame->desc_word[0] = cpu_to_le16(RSI_WIFI_MGMT_Q << 12);
+	cmd_frame->desc_word[1] = cpu_to_le16(RADIO_PARAMS_UPDATE);
+	cmd_frame->desc_word[3] = cpu_to_le16(BIT(0));
+
+	cmd_frame->desc_word[3] |= cpu_to_le16(common->tx_power << 8);
+
+	skb_put(skb, FRAME_DESC_SZ);
+
+	return rsi_send_internal_mgmt_frame(common, skb);
+}
+
+/**
  * rsi_compare() - This function is used to compare two integers
  * @a: pointer to the first integer
  * @b: pointer to the second integer

drivers/net/wireless/rsi/rsi_main.h

···
 	struct cqm_info cqm_info;
 
 	bool hw_data_qs_blocked;
+	
+	int tx_power;
 };
 
 struct rsi_hw {

drivers/net/wireless/rsi/rsi_mgmt.h

···
 	BG_SCAN_PARAMS,
 	BG_SCAN_PROBE_REQ,
 	CW_MODE_REQ,
-	PER_CMD_PKT
+	PER_CMD_PKT,
+	RADIO_PARAMS_UPDATE = 0x29
 };
 
 struct rsi_mac_frame {
···
 int rsi_send_data_pkt(struct rsi_common *common, struct sk_buff *skb);
 int rsi_band_check(struct rsi_common *common);
 int rsi_send_rx_filter_frame(struct rsi_common *common, u16 rx_filter_word);
+int rsi_send_radio_params_update(struct rsi_common *common);
 #endif