/**
 * Copyright (c) 2014 Redpine Signals Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <linux/etherdevice.h>
#include "rsi_mgmt.h"
#include "rsi_common.h"

static struct bootup_params boot_params_20 = {
	.magic_number = cpu_to_le16(0x5aa5),
	.crystal_good_time = 0x0,
	.valid = cpu_to_le32(VALID_20),
	.reserved_for_valids = 0x0,
	.bootup_mode_info = 0x0,
	.digital_loop_back_params = 0x0,
	.rtls_timestamp_en = 0x0,
	.host_spi_intr_cfg = 0x0,
	.device_clk_info = {{
		.pll_config_g = {
			.tapll_info_g = {
				.pll_reg_1 = cpu_to_le16((TA_PLL_N_VAL_20 << 8)|
					      (TA_PLL_M_VAL_20)),
				.pll_reg_2 = cpu_to_le16(TA_PLL_P_VAL_20),
			},
			.pll960_info_g = {
				.pll_reg_1 = cpu_to_le16((PLL960_P_VAL_20 << 8)|
							 (PLL960_N_VAL_20)),
				.pll_reg_2 = cpu_to_le16(PLL960_M_VAL_20),
				.pll_reg_3 = 0x0,
			},
			.afepll_info_g = {
				.pll_reg = cpu_to_le16(0x9f0),
			}
		},
		.switch_clk_g = {
			.switch_clk_info = cpu_to_le16(BIT(3)),
			.bbp_lmac_clk_reg_val = cpu_to_le16(0x121),
			.umac_clock_reg_config = 0x0,
			.qspi_uart_clock_reg_config = 0x0
		}
	},
	{
		.pll_config_g = {
			.tapll_info_g = {
				.pll_reg_1 = cpu_to_le16((TA_PLL_N_VAL_20 << 8)|
							 (TA_PLL_M_VAL_20)),
				.pll_reg_2 = cpu_to_le16(TA_PLL_P_VAL_20),
			},
			.pll960_info_g = {
				.pll_reg_1 = cpu_to_le16((PLL960_P_VAL_20 << 8)|
							 (PLL960_N_VAL_20)),
				.pll_reg_2 = cpu_to_le16(PLL960_M_VAL_20),
				.pll_reg_3 = 0x0,
			},
			.afepll_info_g = {
				.pll_reg = cpu_to_le16(0x9f0),
			}
		},
		.switch_clk_g = {
			.switch_clk_info = 0x0,
			.bbp_lmac_clk_reg_val = 0x0,
			.umac_clock_reg_config = 0x0,
			.qspi_uart_clock_reg_config = 0x0
		}
	},
	{
		.pll_config_g = {
			.tapll_info_g = {
				.pll_reg_1 = cpu_to_le16((TA_PLL_N_VAL_20 << 8)|
							 (TA_PLL_M_VAL_20)),
				.pll_reg_2 = cpu_to_le16(TA_PLL_P_VAL_20),
			},
			.pll960_info_g = {
				.pll_reg_1 = cpu_to_le16((PLL960_P_VAL_20 << 8)|
							 (PLL960_N_VAL_20)),
				.pll_reg_2 = cpu_to_le16(PLL960_M_VAL_20),
				.pll_reg_3 = 0x0,
			},
			.afepll_info_g = {
				.pll_reg = cpu_to_le16(0x9f0),
			}
		},
		.switch_clk_g = {
			.switch_clk_info = 0x0,
			.bbp_lmac_clk_reg_val = 0x0,
			.umac_clock_reg_config = 0x0,
			.qspi_uart_clock_reg_config = 0x0
		}
	} },
	.buckboost_wakeup_cnt = 0x0,
	.pmu_wakeup_wait = 0x0,
	.shutdown_wait_time = 0x0,
	.pmu_slp_clkout_sel = 0x0,
	.wdt_prog_value = 0x0,
	.wdt_soc_rst_delay = 0x0,
	.dcdc_operation_mode = 0x0,
	.soc_reset_wait_cnt = 0x0
};

static struct bootup_params boot_params_40 = {
	.magic_number = cpu_to_le16(0x5aa5),
	.crystal_good_time = 0x0,
	.valid = cpu_to_le32(VALID_40),
	.reserved_for_valids = 0x0,
	.bootup_mode_info = 0x0,
	.digital_loop_back_params = 0x0,
	.rtls_timestamp_en = 0x0,
	.host_spi_intr_cfg = 0x0,
	.device_clk_info = {{
		.pll_config_g = {
			.tapll_info_g = {
				.pll_reg_1 = cpu_to_le16((TA_PLL_N_VAL_40 << 8)|
							 (TA_PLL_M_VAL_40)),
				.pll_reg_2 = cpu_to_le16(TA_PLL_P_VAL_40),
			},
			.pll960_info_g = {
				.pll_reg_1 = cpu_to_le16((PLL960_P_VAL_40 << 8)|
							 (PLL960_N_VAL_40)),
				.pll_reg_2 = cpu_to_le16(PLL960_M_VAL_40),
				.pll_reg_3 = 0x0,
			},
			.afepll_info_g = {
				.pll_reg = cpu_to_le16(0x9f0),
			}
		},
		.switch_clk_g = {
			.switch_clk_info = cpu_to_le16(0x09),
			.bbp_lmac_clk_reg_val = cpu_to_le16(0x1121),
			.umac_clock_reg_config = cpu_to_le16(0x48),
			.qspi_uart_clock_reg_config = 0x0
		}
	},
	{
		.pll_config_g = {
			.tapll_info_g = {
				.pll_reg_1 = cpu_to_le16((TA_PLL_N_VAL_40 << 8)|
							 (TA_PLL_M_VAL_40)),
				.pll_reg_2 = cpu_to_le16(TA_PLL_P_VAL_40),
			},
			.pll960_info_g = {
				.pll_reg_1 = cpu_to_le16((PLL960_P_VAL_40 << 8)|
							 (PLL960_N_VAL_40)),
				.pll_reg_2 = cpu_to_le16(PLL960_M_VAL_40),
				.pll_reg_3 = 0x0,
			},
			.afepll_info_g = {
				.pll_reg = cpu_to_le16(0x9f0),
			}
		},
		.switch_clk_g = {
			.switch_clk_info = 0x0,
			.bbp_lmac_clk_reg_val = 0x0,
			.umac_clock_reg_config = 0x0,
			.qspi_uart_clock_reg_config = 0x0
		}
	},
	{
		.pll_config_g = {
			.tapll_info_g = {
				.pll_reg_1 = cpu_to_le16((TA_PLL_N_VAL_40 << 8)|
							 (TA_PLL_M_VAL_40)),
				.pll_reg_2 = cpu_to_le16(TA_PLL_P_VAL_40),
			},
			.pll960_info_g = {
				.pll_reg_1 = cpu_to_le16((PLL960_P_VAL_40 << 8)|
							 (PLL960_N_VAL_40)),
				.pll_reg_2 = cpu_to_le16(PLL960_M_VAL_40),
				.pll_reg_3 = 0x0,
			},
			.afepll_info_g = {
				.pll_reg = cpu_to_le16(0x9f0),
			}
		},
		.switch_clk_g = {
			.switch_clk_info = 0x0,
			.bbp_lmac_clk_reg_val = 0x0,
			.umac_clock_reg_config = 0x0,
			.qspi_uart_clock_reg_config = 0x0
		}
	} },
	.buckboost_wakeup_cnt = 0x0,
	.pmu_wakeup_wait = 0x0,
	.shutdown_wait_time = 0x0,
	.pmu_slp_clkout_sel = 0x0,
	.wdt_prog_value = 0x0,
	.wdt_soc_rst_delay = 0x0,
	.dcdc_operation_mode = 0x0,
	.soc_reset_wait_cnt = 0x0
};

static u16 mcs[] = {13, 26, 39, 52, 78, 104, 117, 130};

/**
 * rsi_set_default_parameters() - This function sets default parameters.
 * @common: Pointer to the driver private structure.
 *
 * Return: none
 */
static void rsi_set_default_parameters(struct rsi_common *common)
{
	common->band = IEEE80211_BAND_2GHZ;
	common->channel_width = BW_20MHZ;
	common->rts_threshold = IEEE80211_MAX_RTS_THRESHOLD;
	common->channel = 1;
	common->min_rate = 0xffff;
	common->fsm_state = FSM_CARD_NOT_READY;
	common->iface_down = true;
}

/**
 * rsi_set_contention_vals() - This function sets the contention values for the
 *			       backoff procedure.
 * @common: Pointer to the driver private structure.
 *
 * Return: None.
 */
static void rsi_set_contention_vals(struct rsi_common *common)
{
	u8 ii = 0;

	for (; ii < NUM_EDCA_QUEUES; ii++) {
		common->tx_qinfo[ii].wme_params =
			(((common->edca_params[ii].cw_min / 2) +
			  (common->edca_params[ii].aifs)) *
			  WMM_SHORT_SLOT_TIME + SIFS_DURATION);
		common->tx_qinfo[ii].weight = common->tx_qinfo[ii].wme_params;
		common->tx_qinfo[ii].pkt_contended = 0;
	}
}

/**
 * rsi_send_internal_mgmt_frame() - This function sends management frames to
 *				    firmware.Also schedules packet to queue
 *				    for transmission.
 * @common: Pointer to the driver private structure.
 * @skb: Pointer to the socket buffer structure.
 *
 * Return: 0 on success, -1 on failure.
 */
static int rsi_send_internal_mgmt_frame(struct rsi_common *common,
					struct sk_buff *skb)
{
	struct skb_info *tx_params;

	if (skb == NULL) {
		rsi_dbg(ERR_ZONE, "%s: Unable to allocate skb\n", __func__);
		return -ENOMEM;
	}
	tx_params = (struct skb_info *)&IEEE80211_SKB_CB(skb)->driver_data;
	tx_params->flags |= INTERNAL_MGMT_PKT;
	skb_queue_tail(&common->tx_queue[MGMT_SOFT_Q], skb);
	rsi_set_event(&common->tx_thread.event);
	return 0;
}

/**
 * rsi_load_radio_caps() - This function is used to send radio capabilities
 *			   values to firmware.
 * @common: Pointer to the driver private structure.
 *
 * Return: 0 on success, corresponding negative error code on failure.
 */
static int rsi_load_radio_caps(struct rsi_common *common)
{
	struct rsi_radio_caps *radio_caps;
	struct rsi_hw *adapter = common->priv;
	struct ieee80211_hw *hw = adapter->hw;
	u16 inx = 0;
	u8 ii;
	u8 radio_id = 0;
	u16 gc[20] = {0xf0, 0xf0, 0xf0, 0xf0,
		      0xf0, 0xf0, 0xf0, 0xf0,
		      0xf0, 0xf0, 0xf0, 0xf0,
		      0xf0, 0xf0, 0xf0, 0xf0,
		      0xf0, 0xf0, 0xf0, 0xf0};
	struct ieee80211_conf *conf = &hw->conf;
	struct sk_buff *skb;

	rsi_dbg(INFO_ZONE, "%s: Sending rate symbol req frame\n", __func__);

	skb = dev_alloc_skb(sizeof(struct rsi_radio_caps));

	if (!skb) {
		rsi_dbg(ERR_ZONE, "%s: Failed in allocation of skb\n",
			__func__);
		return -ENOMEM;
	}

	memset(skb->data, 0, sizeof(struct rsi_radio_caps));
	radio_caps = (struct rsi_radio_caps *)skb->data;

	radio_caps->desc_word[1] = cpu_to_le16(RADIO_CAPABILITIES);
	radio_caps->desc_word[4] = cpu_to_le16(RSI_RF_TYPE << 8);

	if (common->channel_width == BW_40MHZ) {
		radio_caps->desc_word[7] |= cpu_to_le16(RSI_LMAC_CLOCK_80MHZ);
		radio_caps->desc_word[7] |= cpu_to_le16(RSI_ENABLE_40MHZ);
		if (common->channel_width) {
			radio_caps->desc_word[5] =
				cpu_to_le16(common->channel_width << 12);
			radio_caps->desc_word[5] |= cpu_to_le16(FULL40M_ENABLE);
		}

		if (conf_is_ht40_minus(conf)) {
			radio_caps->desc_word[5] = 0;
			radio_caps->desc_word[5] |=
				cpu_to_le16(LOWER_20_ENABLE);
			radio_caps->desc_word[5] |=
				cpu_to_le16(LOWER_20_ENABLE >> 12);
		}

		if (conf_is_ht40_plus(conf)) {
			radio_caps->desc_word[5] = 0;
			radio_caps->desc_word[5] |=
				cpu_to_le16(UPPER_20_ENABLE);
			radio_caps->desc_word[5] |=
				cpu_to_le16(UPPER_20_ENABLE >> 12);
		}
	}

	radio_caps->desc_word[7] |= cpu_to_le16(radio_id << 8);

	for (ii = 0; ii < MAX_HW_QUEUES; ii++) {
		radio_caps->qos_params[ii].cont_win_min_q = cpu_to_le16(3);
		radio_caps->qos_params[ii].cont_win_max_q = cpu_to_le16(0x3f);
		radio_caps->qos_params[ii].aifsn_val_q = cpu_to_le16(2);
		radio_caps->qos_params[ii].txop_q = 0;
	}

	for (ii = 0; ii < MAX_HW_QUEUES - 4; ii++) {
		radio_caps->qos_params[ii].cont_win_min_q =
			cpu_to_le16(common->edca_params[ii].cw_min);
		radio_caps->qos_params[ii].cont_win_max_q =
			cpu_to_le16(common->edca_params[ii].cw_max);
		radio_caps->qos_params[ii].aifsn_val_q =
			cpu_to_le16((common->edca_params[ii].aifs) << 8);
		radio_caps->qos_params[ii].txop_q =
			cpu_to_le16(common->edca_params[ii].txop);
	}

	memcpy(&common->rate_pwr[0], &gc[0], 40);
	for (ii = 0; ii < 20; ii++)
		radio_caps->gcpd_per_rate[inx++] =
			cpu_to_le16(common->rate_pwr[ii]  & 0x00FF);

	radio_caps->desc_word[0] = cpu_to_le16((sizeof(struct rsi_radio_caps) -
						FRAME_DESC_SZ) |
					       (RSI_WIFI_MGMT_Q << 12));


	skb_put(skb, (sizeof(struct rsi_radio_caps)));

	return rsi_send_internal_mgmt_frame(common, skb);
}

/**
 * rsi_mgmt_pkt_to_core() - This function is the entry point for Mgmt module.
 * @common: Pointer to the driver private structure.
 * @msg: Pointer to received packet.
 * @msg_len: Length of the recieved packet.
 * @type: Type of recieved packet.
 *
 * Return: 0 on success, -1 on failure.
 */
static int rsi_mgmt_pkt_to_core(struct rsi_common *common,
				u8 *msg,
				s32 msg_len,
				u8 type)
{
	struct rsi_hw *adapter = common->priv;
	struct ieee80211_tx_info *info;
	struct skb_info *rx_params;
	u8 pad_bytes = msg[4];
	u8 pkt_recv;
	struct sk_buff *skb;
	char *buffer;

	if (type == RX_DOT11_MGMT) {
		if (!adapter->sc_nvifs)
			return -ENOLINK;

		msg_len -= pad_bytes;
		if ((msg_len <= 0) || (!msg)) {
			rsi_dbg(MGMT_RX_ZONE,
				"%s: Invalid rx msg of len = %d\n",
				__func__, msg_len);
			return -EINVAL;
		}

		skb = dev_alloc_skb(msg_len);
		if (!skb) {
			rsi_dbg(ERR_ZONE, "%s: Failed to allocate skb\n",
				__func__);
			return -ENOMEM;
		}

		buffer = skb_put(skb, msg_len);

		memcpy(buffer,
		       (u8 *)(msg +  FRAME_DESC_SZ + pad_bytes),
		       msg_len);

		pkt_recv = buffer[0];

		info = IEEE80211_SKB_CB(skb);
		rx_params = (struct skb_info *)info->driver_data;
		rx_params->rssi = rsi_get_rssi(msg);
		rx_params->channel = rsi_get_channel(msg);
		rsi_indicate_pkt_to_os(common, skb);
	} else {
		rsi_dbg(MGMT_TX_ZONE, "%s: Internal Packet\n", __func__);
	}

	return 0;
}

/**
 * rsi_hal_send_sta_notify_frame() - This function sends the station notify
 *				     frame to firmware.
 * @common: Pointer to the driver private structure.
 * @opmode: Operating mode of device.
 * @notify_event: Notification about station connection.
 * @bssid: bssid.
 * @qos_enable: Qos is enabled.
 * @aid: Aid (unique for all STA).
 *
 * Return: status: 0 on success, corresponding negative error code on failure.
 */
static int rsi_hal_send_sta_notify_frame(struct rsi_common *common,
					 u8 opmode,
					 u8 notify_event,
					 const unsigned char *bssid,
					 u8 qos_enable,
					 u16 aid)
{
	struct sk_buff *skb = NULL;
	struct rsi_peer_notify *peer_notify;
	u16 vap_id = 0;
	int status;

	rsi_dbg(MGMT_TX_ZONE, "%s: Sending sta notify frame\n", __func__);

	skb = dev_alloc_skb(sizeof(struct rsi_peer_notify));

	if (!skb) {
		rsi_dbg(ERR_ZONE, "%s: Failed in allocation of skb\n",
			__func__);
		return -ENOMEM;
	}

	memset(skb->data, 0, sizeof(struct rsi_peer_notify));
	peer_notify = (struct rsi_peer_notify *)skb->data;

	peer_notify->command = cpu_to_le16(opmode << 1);

	switch (notify_event) {
	case STA_CONNECTED:
		peer_notify->command |= cpu_to_le16(RSI_ADD_PEER);
		break;
	case STA_DISCONNECTED:
		peer_notify->command |= cpu_to_le16(RSI_DELETE_PEER);
		break;
	default:
		break;
	}

	peer_notify->command |= cpu_to_le16((aid & 0xfff) << 4);
	ether_addr_copy(peer_notify->mac_addr, bssid);

	peer_notify->sta_flags = cpu_to_le32((qos_enable) ? 1 : 0);

	peer_notify->desc_word[0] =
		cpu_to_le16((sizeof(struct rsi_peer_notify) - FRAME_DESC_SZ) |
			    (RSI_WIFI_MGMT_Q << 12));
	peer_notify->desc_word[1] = cpu_to_le16(PEER_NOTIFY);
	peer_notify->desc_word[7] |= cpu_to_le16(vap_id << 8);

	skb_put(skb, sizeof(struct rsi_peer_notify));

	status = rsi_send_internal_mgmt_frame(common, skb);

	if (!status && qos_enable) {
		rsi_set_contention_vals(common);
		status = rsi_load_radio_caps(common);
	}
	return status;
}

/**
 * rsi_send_aggregation_params_frame() - This function sends the ampdu
 *					 indication frame to firmware.
 * @common: Pointer to the driver private structure.
 * @tid: traffic identifier.
 * @ssn: ssn.
 * @buf_size: buffer size.
 * @event: notification about station connection.
 *
 * Return: 0 on success, corresponding negative error code on failure.
 */
int rsi_send_aggregation_params_frame(struct rsi_common *common,
				      u16 tid,
				      u16 ssn,
				      u8 buf_size,
				      u8 event)
{
	struct sk_buff *skb = NULL;
	struct rsi_mac_frame *mgmt_frame;
	u8 peer_id = 0;

	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);
	mgmt_frame = (struct rsi_mac_frame *)skb->data;

	rsi_dbg(MGMT_TX_ZONE, "%s: Sending AMPDU indication frame\n", __func__);

	mgmt_frame->desc_word[0] = cpu_to_le16(RSI_WIFI_MGMT_Q << 12);
	mgmt_frame->desc_word[1] = cpu_to_le16(AMPDU_IND);

	if (event == STA_TX_ADDBA_DONE) {
		mgmt_frame->desc_word[4] = cpu_to_le16(ssn);
		mgmt_frame->desc_word[5] = cpu_to_le16(buf_size);
		mgmt_frame->desc_word[7] =
		cpu_to_le16((tid | (START_AMPDU_AGGR << 4) | (peer_id << 8)));
	} else if (event == STA_RX_ADDBA_DONE) {
		mgmt_frame->desc_word[4] = cpu_to_le16(ssn);
		mgmt_frame->desc_word[7] = cpu_to_le16(tid |
						       (START_AMPDU_AGGR << 4) |
						       (RX_BA_INDICATION << 5) |
						       (peer_id << 8));
	} else if (event == STA_TX_DELBA) {
		mgmt_frame->desc_word[7] = cpu_to_le16(tid |
						       (STOP_AMPDU_AGGR << 4) |
						       (peer_id << 8));
	} else if (event == STA_RX_DELBA) {
		mgmt_frame->desc_word[7] = cpu_to_le16(tid |
						       (STOP_AMPDU_AGGR << 4) |
						       (RX_BA_INDICATION << 5) |
						       (peer_id << 8));
	}

	skb_put(skb, FRAME_DESC_SZ);

	return rsi_send_internal_mgmt_frame(common, skb);
}

/**
 * rsi_program_bb_rf() - This function starts base band and RF programming.
 *			 This is called after initial configurations are done.
 * @common: Pointer to the driver private structure.
 *
 * Return: 0 on success, corresponding negative error code on failure.
 */
static int rsi_program_bb_rf(struct rsi_common *common)
{
	struct sk_buff *skb;
	struct rsi_mac_frame *mgmt_frame;

	rsi_dbg(MGMT_TX_ZONE, "%s: Sending program BB/RF 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);
	mgmt_frame = (struct rsi_mac_frame *)skb->data;

	mgmt_frame->desc_word[0] = cpu_to_le16(RSI_WIFI_MGMT_Q << 12);
	mgmt_frame->desc_word[1] = cpu_to_le16(BBP_PROG_IN_TA);
	mgmt_frame->desc_word[4] = cpu_to_le16(common->endpoint << 8);

	if (common->rf_reset) {
		mgmt_frame->desc_word[7] =  cpu_to_le16(RF_RESET_ENABLE);
		rsi_dbg(MGMT_TX_ZONE, "%s: ===> RF RESET REQUEST SENT <===\n",
			__func__);
		common->rf_reset = 0;
	}
	common->bb_rf_prog_count = 1;
	mgmt_frame->desc_word[7] |= cpu_to_le16(PUT_BBP_RESET |
				     BBP_REG_WRITE | (RSI_RF_TYPE << 4));
	skb_put(skb, FRAME_DESC_SZ);

	return rsi_send_internal_mgmt_frame(common, skb);
}

/**
 * rsi_set_vap_capabilities() - This function send vap capability to firmware.
 * @common: Pointer to the driver private structure.
 * @opmode: Operating mode of device.
 *
 * Return: 0 on success, corresponding negative error code on failure.
 */
int rsi_set_vap_capabilities(struct rsi_common *common, enum opmode mode)
{
	struct sk_buff *skb = NULL;
	struct rsi_vap_caps *vap_caps;
	u16 vap_id = 0;

	rsi_dbg(MGMT_TX_ZONE, "%s: Sending VAP capabilities frame\n", __func__);

	skb = dev_alloc_skb(sizeof(struct rsi_vap_caps));
	if (!skb) {
		rsi_dbg(ERR_ZONE, "%s: Failed in allocation of skb\n",
			__func__);
		return -ENOMEM;
	}

	memset(skb->data, 0, sizeof(struct rsi_vap_caps));
	vap_caps = (struct rsi_vap_caps *)skb->data;

	vap_caps->desc_word[0] = cpu_to_le16((sizeof(struct rsi_vap_caps) -
					     FRAME_DESC_SZ) |
					     (RSI_WIFI_MGMT_Q << 12));
	vap_caps->desc_word[1] = cpu_to_le16(VAP_CAPABILITIES);
	vap_caps->desc_word[4] = cpu_to_le16(mode |
					     (common->channel_width << 8));
	vap_caps->desc_word[7] = cpu_to_le16((vap_id << 8) |
					     (common->mac_id << 4) |
					     common->radio_id);

	memcpy(vap_caps->mac_addr, common->mac_addr, IEEE80211_ADDR_LEN);
	vap_caps->keep_alive_period = cpu_to_le16(90);
	vap_caps->frag_threshold = cpu_to_le16(IEEE80211_MAX_FRAG_THRESHOLD);

	vap_caps->rts_threshold = cpu_to_le16(common->rts_threshold);
	vap_caps->default_mgmt_rate = 0;
	if (conf_is_ht40(&common->priv->hw->conf)) {
		vap_caps->default_ctrl_rate =
				cpu_to_le32(RSI_RATE_6 | FULL40M_ENABLE << 16);
	} else {
		vap_caps->default_ctrl_rate = cpu_to_le32(RSI_RATE_6);
	}
	vap_caps->default_data_rate = 0;
	vap_caps->beacon_interval = cpu_to_le16(200);
	vap_caps->dtim_period = cpu_to_le16(4);

	skb_put(skb, sizeof(*vap_caps));

	return rsi_send_internal_mgmt_frame(common, skb);
}

/**
 * rsi_hal_load_key() - This function is used to load keys within the firmware.
 * @common: Pointer to the driver private structure.
 * @data: Pointer to the key data.
 * @key_len: Key length to be loaded.
 * @key_type: Type of key: GROUP/PAIRWISE.
 * @key_id: Key index.
 * @cipher: Type of cipher used.
 *
 * Return: 0 on success, -1 on failure.
 */
int rsi_hal_load_key(struct rsi_common *common,
		     u8 *data,
		     u16 key_len,
		     u8 key_type,
		     u8 key_id,
		     u32 cipher)
{
	struct sk_buff *skb = NULL;
	struct rsi_set_key *set_key;
	u16 key_descriptor = 0;

	rsi_dbg(MGMT_TX_ZONE, "%s: Sending load key frame\n", __func__);

	skb = dev_alloc_skb(sizeof(struct rsi_set_key));
	if (!skb) {
		rsi_dbg(ERR_ZONE, "%s: Failed in allocation of skb\n",
			__func__);
		return -ENOMEM;
	}

	memset(skb->data, 0, sizeof(struct rsi_set_key));
	set_key = (struct rsi_set_key *)skb->data;

	if ((cipher == WLAN_CIPHER_SUITE_WEP40) ||
	    (cipher == WLAN_CIPHER_SUITE_WEP104)) {
		key_len += 1;
		key_descriptor |= BIT(2);
		if (key_len >= 13)
			key_descriptor |= BIT(3);
	} else if (cipher != KEY_TYPE_CLEAR) {
		key_descriptor |= BIT(4);
		if (key_type == RSI_PAIRWISE_KEY)
			key_id = 0;
		if (cipher == WLAN_CIPHER_SUITE_TKIP)
			key_descriptor |= BIT(5);
	}
	key_descriptor |= (key_type | BIT(13) | (key_id << 14));

	set_key->desc_word[0] = cpu_to_le16((sizeof(struct rsi_set_key) -
					    FRAME_DESC_SZ) |
					    (RSI_WIFI_MGMT_Q << 12));
	set_key->desc_word[1] = cpu_to_le16(SET_KEY_REQ);
	set_key->desc_word[4] = cpu_to_le16(key_descriptor);

	if ((cipher == WLAN_CIPHER_SUITE_WEP40) ||
	    (cipher == WLAN_CIPHER_SUITE_WEP104)) {
		memcpy(&set_key->key[key_id][1],
		       data,
		       key_len * 2);
	} else {
		memcpy(&set_key->key[0][0], data, key_len);
	}

	memcpy(set_key->tx_mic_key, &data[16], 8);
	memcpy(set_key->rx_mic_key, &data[24], 8);

	skb_put(skb, sizeof(struct rsi_set_key));

	return rsi_send_internal_mgmt_frame(common, skb);
}

/*
 * rsi_load_bootup_params() - This function send bootup params to the firmware.
 * @common: Pointer to the driver private structure.
 *
 * Return: 0 on success, corresponding error code on failure.
 */
static int rsi_load_bootup_params(struct rsi_common *common)
{
	struct sk_buff *skb;
	struct rsi_boot_params *boot_params;

	rsi_dbg(MGMT_TX_ZONE, "%s: Sending boot params frame\n", __func__);
	skb = dev_alloc_skb(sizeof(struct rsi_boot_params));
	if (!skb) {
		rsi_dbg(ERR_ZONE, "%s: Failed in allocation of skb\n",
			__func__);
		return -ENOMEM;
	}

	memset(skb->data, 0, sizeof(struct rsi_boot_params));
	boot_params = (struct rsi_boot_params *)skb->data;

	rsi_dbg(MGMT_TX_ZONE, "%s:\n", __func__);

	if (common->channel_width == BW_40MHZ) {
		memcpy(&boot_params->bootup_params,
		       &boot_params_40,
		       sizeof(struct bootup_params));
		rsi_dbg(MGMT_TX_ZONE, "%s: Packet 40MHZ <=== %d\n", __func__,
			UMAC_CLK_40BW);
		boot_params->desc_word[7] = cpu_to_le16(UMAC_CLK_40BW);
	} else {
		memcpy(&boot_params->bootup_params,
		       &boot_params_20,
		       sizeof(struct bootup_params));
		if (boot_params_20.valid != cpu_to_le32(VALID_20)) {
			boot_params->desc_word[7] = cpu_to_le16(UMAC_CLK_20BW);
			rsi_dbg(MGMT_TX_ZONE,
				"%s: Packet 20MHZ <=== %d\n", __func__,
				UMAC_CLK_20BW);
		} else {
			boot_params->desc_word[7] = cpu_to_le16(UMAC_CLK_40MHZ);
			rsi_dbg(MGMT_TX_ZONE,
				"%s: Packet 20MHZ <=== %d\n", __func__,
				UMAC_CLK_40MHZ);
		}
	}

	/**
	 * Bit{0:11} indicates length of the Packet
	 * Bit{12:15} indicates host queue number
	 */
	boot_params->desc_word[0] = cpu_to_le16(sizeof(struct bootup_params) |
				    (RSI_WIFI_MGMT_Q << 12));
	boot_params->desc_word[1] = cpu_to_le16(BOOTUP_PARAMS_REQUEST);

	skb_put(skb, sizeof(struct rsi_boot_params));

	return rsi_send_internal_mgmt_frame(common, skb);
}

/**
 * rsi_send_reset_mac() - This function prepares reset MAC request and sends an
 *			  internal management frame to indicate it to firmware.
 * @common: Pointer to the driver private structure.
 *
 * Return: 0 on success, corresponding error code on failure.
 */
static int rsi_send_reset_mac(struct rsi_common *common)
{
	struct sk_buff *skb;
	struct rsi_mac_frame *mgmt_frame;

	rsi_dbg(MGMT_TX_ZONE, "%s: Sending reset MAC 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);
	mgmt_frame = (struct rsi_mac_frame *)skb->data;

	mgmt_frame->desc_word[0] = cpu_to_le16(RSI_WIFI_MGMT_Q << 12);
	mgmt_frame->desc_word[1] = cpu_to_le16(RESET_MAC_REQ);
	mgmt_frame->desc_word[4] = cpu_to_le16(RETRY_COUNT << 8);

	skb_put(skb, FRAME_DESC_SZ);

	return rsi_send_internal_mgmt_frame(common, skb);
}

/**
 * rsi_set_channel() - This function programs the channel.
 * @common: Pointer to the driver private structure.
 * @channel: Channel value to be set.
 *
 * Return: 0 on success, corresponding error code on failure.
 */
int rsi_set_channel(struct rsi_common *common, u16 channel)
{
	struct sk_buff *skb = NULL;
	struct rsi_mac_frame *mgmt_frame;

	rsi_dbg(MGMT_TX_ZONE,
		"%s: Sending scan req frame\n", __func__);

	if (common->band == IEEE80211_BAND_5GHZ) {
		if ((channel >= 36) && (channel <= 64))
			channel = ((channel - 32) / 4);
		else if ((channel > 64) && (channel <= 140))
			channel = ((channel - 102) / 4) + 8;
		else if (channel >= 149)
			channel = ((channel - 151) / 4) + 18;
		else
			return -EINVAL;
	} else {
		if (channel > 14) {
			rsi_dbg(ERR_ZONE, "%s: Invalid chno %d, band = %d\n",
				__func__, channel, common->band);
			return -EINVAL;
		}
	}

	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);
	mgmt_frame = (struct rsi_mac_frame *)skb->data;

	mgmt_frame->desc_word[0] = cpu_to_le16(RSI_WIFI_MGMT_Q << 12);
	mgmt_frame->desc_word[1] = cpu_to_le16(SCAN_REQUEST);
	mgmt_frame->desc_word[4] = cpu_to_le16(channel);

	mgmt_frame->desc_word[7] = cpu_to_le16(PUT_BBP_RESET |
					       BBP_REG_WRITE |
					       (RSI_RF_TYPE << 4));

	mgmt_frame->desc_word[5] = cpu_to_le16(0x01);

	if (common->channel_width == BW_40MHZ)
		mgmt_frame->desc_word[5] |= cpu_to_le16(0x1 << 8);

	common->channel = channel;

	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
 *
 * Return: 0 if both are equal, -1 if the first is smaller, else 1
 */
static int rsi_compare(const void *a, const void *b)
{
	u16 _a = *(const u16 *)(a);
	u16 _b = *(const u16 *)(b);

	if (_a > _b)
		return -1;

	if (_a < _b)
		return 1;

	return 0;
}

/**
 * rsi_map_rates() - This function is used to map selected rates to hw rates.
 * @rate: The standard rate to be mapped.
 * @offset: Offset that will be returned.
 *
 * Return: 0 if it is a mcs rate, else 1
 */
static bool rsi_map_rates(u16 rate, int *offset)
{
	int kk;
	for (kk = 0; kk < ARRAY_SIZE(rsi_mcsrates); kk++) {
		if (rate == mcs[kk]) {
			*offset = kk;
			return false;
		}
	}

	for (kk = 0; kk < ARRAY_SIZE(rsi_rates); kk++) {
		if (rate == rsi_rates[kk].bitrate / 5) {
			*offset = kk;
			break;
		}
	}
	return true;
}

/**
 * rsi_send_auto_rate_request() - This function is to set rates for connection
 *				  and send autorate request to firmware.
 * @common: Pointer to the driver private structure.
 *
 * Return: 0 on success, corresponding error code on failure.
 */
static int rsi_send_auto_rate_request(struct rsi_common *common)
{
	struct sk_buff *skb;
	struct rsi_auto_rate *auto_rate;
	int ii = 0, jj = 0, kk = 0;
	struct ieee80211_hw *hw = common->priv->hw;
	u8 band = hw->conf.chandef.chan->band;
	u8 num_supported_rates = 0;
	u8 rate_offset = 0;
	u32 rate_bitmap = common->bitrate_mask[band];

	u16 *selected_rates, min_rate;

	skb = dev_alloc_skb(sizeof(struct rsi_auto_rate));
	if (!skb) {
		rsi_dbg(ERR_ZONE, "%s: Failed in allocation of skb\n",
			__func__);
		return -ENOMEM;
	}

	selected_rates = kmalloc(2 * RSI_TBL_SZ, GFP_KERNEL);
	if (!selected_rates) {
		rsi_dbg(ERR_ZONE, "%s: Failed in allocation of mem\n",
			__func__);
		dev_kfree_skb(skb);
		return -ENOMEM;
	}

	memset(skb->data, 0, sizeof(struct rsi_auto_rate));
	memset(selected_rates, 0, 2 * RSI_TBL_SZ);

	auto_rate = (struct rsi_auto_rate *)skb->data;

	auto_rate->aarf_rssi = cpu_to_le16(((u16)3 << 6) | (u16)(18 & 0x3f));
	auto_rate->collision_tolerance = cpu_to_le16(3);
	auto_rate->failure_limit = cpu_to_le16(3);
	auto_rate->initial_boundary = cpu_to_le16(3);
	auto_rate->max_threshold_limt = cpu_to_le16(27);

	auto_rate->desc_word[1] = cpu_to_le16(AUTO_RATE_IND);

	if (common->channel_width == BW_40MHZ)
		auto_rate->desc_word[7] |= cpu_to_le16(1);

	if (band == IEEE80211_BAND_2GHZ)
		min_rate = STD_RATE_01;
	else
		min_rate = STD_RATE_06;

	for (ii = 0, jj = 0; ii < ARRAY_SIZE(rsi_rates); ii++) {
		if (rate_bitmap & BIT(ii)) {
			selected_rates[jj++] = (rsi_rates[ii].bitrate / 5);
			rate_offset++;
		}
	}
	num_supported_rates = jj;

	if (common->vif_info[0].is_ht) {
		for (ii = 0; ii < ARRAY_SIZE(mcs); ii++)
			selected_rates[jj++] = mcs[ii];
		num_supported_rates += ARRAY_SIZE(mcs);
		rate_offset += ARRAY_SIZE(mcs);
	}

	if (rate_offset < (RSI_TBL_SZ / 2) - 1) {
		for (ii = jj; ii < (RSI_TBL_SZ / 2); ii++) {
			selected_rates[jj++] = min_rate;
			rate_offset++;
		}
	}

	sort(selected_rates, jj, sizeof(u16), &rsi_compare, NULL);

	/* mapping the rates to RSI rates */
	for (ii = 0; ii < jj; ii++) {
		if (rsi_map_rates(selected_rates[ii], &kk)) {
			auto_rate->supported_rates[ii] =
				cpu_to_le16(rsi_rates[kk].hw_value);
		} else {
			auto_rate->supported_rates[ii] =
				cpu_to_le16(rsi_mcsrates[kk]);
		}
	}

	/* loading HT rates in the bottom half of the auto rate table */
	if (common->vif_info[0].is_ht) {
		if (common->vif_info[0].sgi)
			auto_rate->supported_rates[rate_offset++] =
				cpu_to_le16(RSI_RATE_MCS7_SG);

		for (ii = rate_offset, kk = ARRAY_SIZE(rsi_mcsrates) - 1;
		     ii < rate_offset + 2 * ARRAY_SIZE(rsi_mcsrates); ii++) {
			if (common->vif_info[0].sgi)
				auto_rate->supported_rates[ii++] =
					cpu_to_le16(rsi_mcsrates[kk] | BIT(9));
			auto_rate->supported_rates[ii] =
				cpu_to_le16(rsi_mcsrates[kk--]);
		}

		for (; ii < RSI_TBL_SZ; ii++) {
			auto_rate->supported_rates[ii] =
				cpu_to_le16(rsi_mcsrates[0]);
		}
	}

	auto_rate->num_supported_rates = cpu_to_le16(num_supported_rates * 2);
	auto_rate->moderate_rate_inx = cpu_to_le16(num_supported_rates / 2);
	auto_rate->desc_word[7] |= cpu_to_le16(0 << 8);
	num_supported_rates *= 2;

	auto_rate->desc_word[0] = cpu_to_le16((sizeof(*auto_rate) -
					       FRAME_DESC_SZ) |
					       (RSI_WIFI_MGMT_Q << 12));

	skb_put(skb,
		sizeof(struct rsi_auto_rate));
	kfree(selected_rates);

	return rsi_send_internal_mgmt_frame(common, skb);
}

/**
 * rsi_inform_bss_status() - This function informs about bss status with the
 *			     help of sta notify params by sending an internal
 *			     management frame to firmware.
 * @common: Pointer to the driver private structure.
 * @status: Bss status type.
 * @bssid: Bssid.
 * @qos_enable: Qos is enabled.
 * @aid: Aid (unique for all STAs).
 *
 * Return: None.
 */
void rsi_inform_bss_status(struct rsi_common *common,
			   u8 status,
			   const unsigned char *bssid,
			   u8 qos_enable,
			   u16 aid)
{
	if (status) {
		rsi_hal_send_sta_notify_frame(common,
					      NL80211_IFTYPE_STATION,
					      STA_CONNECTED,
					      bssid,
					      qos_enable,
					      aid);
		if (common->min_rate == 0xffff)
			rsi_send_auto_rate_request(common);
	} else {
		rsi_hal_send_sta_notify_frame(common,
					      NL80211_IFTYPE_STATION,
					      STA_DISCONNECTED,
					      bssid,
					      qos_enable,
					      aid);
	}
}

/**
 * rsi_eeprom_read() - This function sends a frame to read the mac address
 *		       from the eeprom.
 * @common: Pointer to the driver private structure.
 *
 * Return: 0 on success, -1 on failure.
 */
static int rsi_eeprom_read(struct rsi_common *common)
{
	struct rsi_mac_frame *mgmt_frame;
	struct sk_buff *skb;

	rsi_dbg(MGMT_TX_ZONE, "%s: Sending EEPROM read req 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);
	mgmt_frame = (struct rsi_mac_frame *)skb->data;

	/* FrameType */
	mgmt_frame->desc_word[1] = cpu_to_le16(EEPROM_READ_TYPE);
	mgmt_frame->desc_word[0] = cpu_to_le16(RSI_WIFI_MGMT_Q << 12);
	/* Number of bytes to read */
	mgmt_frame->desc_word[3] = cpu_to_le16(ETH_ALEN +
					       WLAN_MAC_MAGIC_WORD_LEN +
					       WLAN_HOST_MODE_LEN +
					       WLAN_FW_VERSION_LEN);
	/* Address to read */
	mgmt_frame->desc_word[4] = cpu_to_le16(WLAN_MAC_EEPROM_ADDR);

	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.
 *
 * Return: 0 on success, -1 on failure.
 */
static int rsi_handle_ta_confirm_type(struct rsi_common *common,
				      u8 *msg)
{
	u8 sub_type = (msg[15] & 0xff);

	switch (sub_type) {
	case BOOTUP_PARAMS_REQUEST:
		rsi_dbg(FSM_ZONE, "%s: Boot up params confirm received\n",
			__func__);
		if (common->fsm_state == FSM_BOOT_PARAMS_SENT) {
			if (rsi_eeprom_read(common)) {
				common->fsm_state = FSM_CARD_NOT_READY;
				goto out;
			} else {
				common->fsm_state = FSM_EEPROM_READ_MAC_ADDR;
			}
		} else {
			rsi_dbg(ERR_ZONE,
				"%s: Received bootup params cfm in %d state\n",
				 __func__, common->fsm_state);
			return 0;
		}
		break;

	case EEPROM_READ_TYPE:
		if (common->fsm_state == FSM_EEPROM_READ_MAC_ADDR) {
			if (msg[16] == MAGIC_WORD) {
				u8 offset = (FRAME_DESC_SZ + WLAN_HOST_MODE_LEN
					     + WLAN_MAC_MAGIC_WORD_LEN);
				memcpy(common->mac_addr,
				       &msg[offset],
				       ETH_ALEN);
				memcpy(&common->fw_ver,
				       &msg[offset + ETH_ALEN],
				       sizeof(struct version_info));

			} else {
				common->fsm_state = FSM_CARD_NOT_READY;
				break;
			}
			if (rsi_send_reset_mac(common))
				goto out;
			else
				common->fsm_state = FSM_RESET_MAC_SENT;
		} else {
			rsi_dbg(ERR_ZONE,
				"%s: Received eeprom mac addr in %d state\n",
				__func__, common->fsm_state);
			return 0;
		}
		break;

	case RESET_MAC_REQ:
		if (common->fsm_state == FSM_RESET_MAC_SENT) {
			rsi_dbg(FSM_ZONE, "%s: Reset MAC cfm received\n",
				__func__);

			if (rsi_load_radio_caps(common))
				goto out;
			else
				common->fsm_state = FSM_RADIO_CAPS_SENT;
		} else {
			rsi_dbg(ERR_ZONE,
				"%s: Received reset mac cfm in %d state\n",
				 __func__, common->fsm_state);
			return 0;
		}
		break;

	case RADIO_CAPABILITIES:
		if (common->fsm_state == FSM_RADIO_CAPS_SENT) {
			common->rf_reset = 1;
			if (rsi_program_bb_rf(common)) {
				goto out;
			} else {
				common->fsm_state = FSM_BB_RF_PROG_SENT;
				rsi_dbg(FSM_ZONE, "%s: Radio cap cfm received\n",
					__func__);
			}
		} else {
			rsi_dbg(ERR_ZONE,
				"%s: Received radio caps cfm in %d state\n",
				 __func__, common->fsm_state);
			return 0;
		}
		break;

	case BB_PROG_VALUES_REQUEST:
	case RF_PROG_VALUES_REQUEST:
	case BBP_PROG_IN_TA:
		rsi_dbg(FSM_ZONE, "%s: BB/RF cfm received\n", __func__);
		if (common->fsm_state == FSM_BB_RF_PROG_SENT) {
			common->bb_rf_prog_count--;
			if (!common->bb_rf_prog_count) {
				common->fsm_state = FSM_MAC_INIT_DONE;
				return rsi_mac80211_attach(common);
			}
		} else {
			goto out;
		}
		break;

	default:
		rsi_dbg(INFO_ZONE, "%s: Invalid TA confirm pkt received\n",
			__func__);
		break;
	}
	return 0;
out:
	rsi_dbg(ERR_ZONE, "%s: Unable to send pkt/Invalid frame received\n",
		__func__);
	return -EINVAL;
}

/**
 * rsi_mgmt_pkt_recv() - This function processes the management packets
 *			 recieved from the hardware.
 * @common: Pointer to the driver private structure.
 * @msg: Pointer to the received packet.
 *
 * Return: 0 on success, -1 on failure.
 */
int rsi_mgmt_pkt_recv(struct rsi_common *common, u8 *msg)
{
	s32 msg_len = (le16_to_cpu(*(__le16 *)&msg[0]) & 0x0fff);
	u16 msg_type = (msg[2]);
	int ret;

	rsi_dbg(FSM_ZONE, "%s: Msg Len: %d, Msg Type: %4x\n",
		__func__, msg_len, msg_type);

	if (msg_type == TA_CONFIRM_TYPE) {
		return rsi_handle_ta_confirm_type(common, msg);
	} else if (msg_type == CARD_READY_IND) {
		rsi_dbg(FSM_ZONE, "%s: Card ready indication received\n",
			__func__);
		if (common->fsm_state == FSM_CARD_NOT_READY) {
			rsi_set_default_parameters(common);

			ret = rsi_load_bootup_params(common);
			if (ret)
				return ret;
			else
				common->fsm_state = FSM_BOOT_PARAMS_SENT;
		} else {
			return -EINVAL;
		}
	} else if (msg_type == TX_STATUS_IND) {
		if (msg[15] == PROBEREQ_CONFIRM) {
			common->mgmt_q_block = false;
			rsi_dbg(FSM_ZONE, "%s: Probe confirm received\n",
				__func__);
		}
	} else {
		return rsi_mgmt_pkt_to_core(common, msg, msg_len, msg_type);
	}
	return 0;
}