rsi: Add support for antenna selection

RSI 9113 device supports single antenna for tx and rx. Support for using
external is added. This can be configured from user space using iw.

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

drivers/net/wireless/rsi/rsi_91x_mac80211.c

···
 	return 0;
 }
 
+/**
+ * rsi_mac80211_set_antenna() - This function is used to configure
+ *				tx and rx antennas.
+ * @hw: Pointer to the ieee80211_hw structure.
+ * @tx_ant: Bitmap for tx antenna
+ * @rx_ant: Bitmap for rx antenna
+ *
+ * Return: 0 on success, Negative error code on failure.
+ */
+static int rsi_mac80211_set_antenna(struct ieee80211_hw *hw,
+				    u32 tx_ant, u32 rx_ant)
+{
+	struct rsi_hw *adapter = hw->priv;
+	struct rsi_common *common = adapter->priv;
+	u8 antenna = 0;
+
+	if (tx_ant > 1 || rx_ant > 1) {
+		rsi_dbg(ERR_ZONE,
+			"Invalid antenna selection (tx: %d, rx:%d)\n",
+			tx_ant, rx_ant);
+		rsi_dbg(ERR_ZONE,
+			"Use 0 for int_ant, 1 for ext_ant\n");
+		return -EINVAL; 
+	}
+
+	rsi_dbg(INFO_ZONE, "%s: Antenna map Tx %x Rx %d\n",
+			__func__, tx_ant, rx_ant);
+
+	mutex_lock(&common->mutex);
+
+	antenna = tx_ant ? ANTENNA_SEL_UFL : ANTENNA_SEL_INT;
+	if (common->ant_in_use != antenna)
+		if (rsi_set_antenna(common, antenna))
+			goto fail_set_antenna;
+
+	rsi_dbg(INFO_ZONE, "(%s) Antenna path configured successfully\n",
+		tx_ant ? "UFL" : "INT");
+
+	common->ant_in_use = antenna;
+	
+	mutex_unlock(&common->mutex);
+	
+	return 0;
+
+fail_set_antenna:
+	rsi_dbg(ERR_ZONE, "%s: Failed.\n", __func__);
+	mutex_unlock(&common->mutex);
+	return -EINVAL;
+}
+
+/**
+ * rsi_mac80211_get_antenna() - This function is used to configure 
+ * 				tx and rx antennas.
+ *
+ * @hw: Pointer to the ieee80211_hw structure.
+ * @tx_ant: Bitmap for tx antenna
+ * @rx_ant: Bitmap for rx antenna
+ * 
+ * Return: 0 on success, -1 on failure.
+ */
+static int rsi_mac80211_get_antenna(struct ieee80211_hw *hw,
+				    u32 *tx_ant, u32 *rx_ant)
+{
+	struct rsi_hw *adapter = hw->priv;
+	struct rsi_common *common = adapter->priv;
+
+	mutex_lock(&common->mutex);
+
+	*tx_ant = (common->ant_in_use == ANTENNA_SEL_UFL) ? 1 : 0;
+	*rx_ant = 0;
+
+	mutex_unlock(&common->mutex);
+	
+	return 0;	
+}
+
 static struct ieee80211_ops mac80211_ops = {
 	.tx = rsi_mac80211_tx,
 	.start = rsi_mac80211_start,
···
 	.ampdu_action = rsi_mac80211_ampdu_action,
 	.sta_add = rsi_mac80211_sta_add,
 	.sta_remove = rsi_mac80211_sta_remove,
+	.set_antenna = rsi_mac80211_set_antenna,
+	.get_antenna = rsi_mac80211_get_antenna,
 };
 
 /**

drivers/net/wireless/rsi/rsi_91x_mgmt.c

···
 }
 
 /**
+ * rsi_set_antenna() - This fuction send antenna configuration request
+ *		       to device
+ *
+ * @common: Pointer to the driver private structure.
+ * @antenna: bitmap for tx antenna selection
+ *
+ * Return: 0 on Success, negative error code on failure
+ */
+int rsi_set_antenna(struct rsi_common *common, u8 antenna)
+{
+	struct rsi_mac_frame *cmd_frame;
+	struct sk_buff *skb;
+
+	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[1] = cpu_to_le16(ANT_SEL_FRAME);
+	cmd_frame->desc_word[3] = cpu_to_le16(antenna & 0x00ff);
+	cmd_frame->desc_word[0] = cpu_to_le16(RSI_WIFI_MGMT_Q << 12);
+
+	skb_put(skb, FRAME_DESC_SZ);
+
+	return rsi_send_internal_mgmt_frame(common, skb);
+}
+
+/**
  * rsi_handle_ta_confirm_type() - This function handles the confirm frames.
  * @common: Pointer to the driver private structure.
  * @msg: Pointer to received packet.

drivers/net/wireless/rsi/rsi_main.h

···
 	bool hw_data_qs_blocked;
 	
 	int tx_power;
+	u8 ant_in_use;
 };
 
 struct rsi_hw {

drivers/net/wireless/rsi/rsi_mgmt.h

···
 #define RSI_SUPP_FILTERS	(FIF_ALLMULTI | FIF_PROBE_REQ |\
 				 FIF_BCN_PRBRESP_PROMISC)
 
+#define ANTENNA_SEL_INT			0x02 /* RF_OUT_2 / Integerated */
+#define ANTENNA_SEL_UFL			0x03 /* RF_OUT_1 / U.FL */
+
 /* Rx filter word definitions */
 #define PROMISCOUS_MODE			BIT(0)
 #define ALLOW_DATA_ASSOC_PEER		BIT(1)
···
 	BG_SCAN_PROBE_REQ,
 	CW_MODE_REQ,
 	PER_CMD_PKT,
+	ANT_SEL_FRAME = 0x20,
 	RADIO_PARAMS_UPDATE = 0x29
 };
 
···
 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);
+int rsi_set_antenna(struct rsi_common *common, u8 antenna);
 #endif