1. 根目录:
2. drivers
3. net
4. wireless
5. mwifiex
6. txrx.c

/*
 * Marvell Wireless LAN device driver: generic TX/RX data handling
 *
 * Copyright (C) 2011, Marvell International Ltd.
 *
 * This software file (the "File") is distributed by Marvell International
 * Ltd. under the terms of the GNU General Public License Version 2, June 1991
 * (the "License").  You may use, redistribute and/or modify this File in
 * accordance with the terms and conditions of the License, a copy of which
 * is available by writing to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or on the
 * worldwide web at http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
 *
 * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
 * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
 * this warranty disclaimer.
 */

#include "decl.h"
#include "ioctl.h"
#include "util.h"
#include "fw.h"
#include "main.h"
#include "wmm.h"

/*
 * This function processes the received buffer.
 *
 * Main responsibility of this function is to parse the RxPD to
 * identify the correct interface this packet is headed for and
 * forwarding it to the associated handling function, where the
 * packet will be further processed and sent to kernel/upper layer
 * if required.
 */
int mwifiex_handle_rx_packet(struct mwifiex_adapter *adapter,
			     struct sk_buff *skb)
{
	struct mwifiex_private *priv =
		mwifiex_get_priv(adapter, MWIFIEX_BSS_ROLE_ANY);
	struct rxpd *local_rx_pd;
	struct mwifiex_rxinfo *rx_info = MWIFIEX_SKB_RXCB(skb);
	int ret;

	local_rx_pd = (struct rxpd *) (skb->data);
	/* Get the BSS number from rxpd, get corresponding priv */
	priv = mwifiex_get_priv_by_id(adapter, local_rx_pd->bss_num &
				      BSS_NUM_MASK, local_rx_pd->bss_type);
	if (!priv)
		priv = mwifiex_get_priv(adapter, MWIFIEX_BSS_ROLE_ANY);

	if (!priv) {
		dev_err(adapter->dev, "data: priv not found. Drop RX packet\n");
		dev_kfree_skb_any(skb);
		return -1;
	}

	rx_info->bss_num = priv->bss_num;
	rx_info->bss_type = priv->bss_type;

	if (priv->bss_role == MWIFIEX_BSS_ROLE_UAP)
		ret = mwifiex_process_uap_rx_packet(priv, skb);
	else
		ret = mwifiex_process_sta_rx_packet(priv, skb);

	/* Decrement RX pending counter for each packet */
	if (adapter->if_ops.data_complete)
		adapter->if_ops.data_complete(adapter);

	return ret;
}
EXPORT_SYMBOL_GPL(mwifiex_handle_rx_packet);

/*
 * This function sends a packet to device.
 *
 * It processes the packet to add the TxPD, checks condition and
 * sends the processed packet to firmware for transmission.
 *
 * On successful completion, the function calls the completion callback
 * and logs the time.
 */
int mwifiex_process_tx(struct mwifiex_private *priv, struct sk_buff *skb,
		       struct mwifiex_tx_param *tx_param)
{
	int ret = -1;
	struct mwifiex_adapter *adapter = priv->adapter;
	u8 *head_ptr;
	struct txpd *local_tx_pd = NULL;

	if (priv->bss_role == MWIFIEX_BSS_ROLE_UAP)
		head_ptr = mwifiex_process_uap_txpd(priv, skb);
	else
		head_ptr = mwifiex_process_sta_txpd(priv, skb);

	if (head_ptr) {
		if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA)
			local_tx_pd =
				(struct txpd *) (head_ptr + INTF_HEADER_LEN);
		if (adapter->iface_type == MWIFIEX_USB) {
			adapter->data_sent = true;
			skb_pull(skb, INTF_HEADER_LEN);
			ret = adapter->if_ops.host_to_card(adapter,
							   MWIFIEX_USB_EP_DATA,
							   skb, NULL);
		} else {
			ret = adapter->if_ops.host_to_card(adapter,
							   MWIFIEX_TYPE_DATA,
							   skb, tx_param);
		}
	}

	switch (ret) {
	case -ENOSR:
		dev_dbg(adapter->dev, "data: -ENOSR is returned\n");
		break;
	case -EBUSY:
		if ((GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA) &&
		    (adapter->pps_uapsd_mode) && (adapter->tx_lock_flag)) {
				priv->adapter->tx_lock_flag = false;
				if (local_tx_pd)
					local_tx_pd->flags = 0;
		}
		dev_dbg(adapter->dev, "data: -EBUSY is returned\n");
		break;
	case -1:
		if (adapter->iface_type != MWIFIEX_PCIE)
			adapter->data_sent = false;
		dev_err(adapter->dev, "mwifiex_write_data_async failed: 0x%X\n",
			ret);
		adapter->dbg.num_tx_host_to_card_failure++;
		mwifiex_write_data_complete(adapter, skb, 0, ret);
		break;
	case -EINPROGRESS:
		if (adapter->iface_type != MWIFIEX_PCIE)
			adapter->data_sent = false;
		break;
	case 0:
		mwifiex_write_data_complete(adapter, skb, 0, ret);
		break;
	default:
		break;
	}

	return ret;
}

/*
 * Packet send completion callback handler.
 *
 * It either frees the buffer directly or forwards it to another
 * completion callback which checks conditions, updates statistics,
 * wakes up stalled traffic queue if required, and then frees the buffer.
 */
int mwifiex_write_data_complete(struct mwifiex_adapter *adapter,
				struct sk_buff *skb, int aggr, int status)
{
	struct mwifiex_private *priv;
	struct mwifiex_txinfo *tx_info;
	struct netdev_queue *txq;
	int index;

	if (!skb)
		return 0;

	tx_info = MWIFIEX_SKB_TXCB(skb);
	priv = mwifiex_get_priv_by_id(adapter, tx_info->bss_num,
				      tx_info->bss_type);
	if (!priv)
		goto done;

	if (adapter->iface_type == MWIFIEX_USB)
		adapter->data_sent = false;

	mwifiex_set_trans_start(priv->netdev);
	if (!status) {
		priv->stats.tx_packets++;
		priv->stats.tx_bytes += tx_info->pkt_len;
		if (priv->tx_timeout_cnt)
			priv->tx_timeout_cnt = 0;
	} else {
		priv->stats.tx_errors++;
	}

	if (tx_info->flags & MWIFIEX_BUF_FLAG_BRIDGED_PKT)
		atomic_dec_return(&adapter->pending_bridged_pkts);

	if (aggr)
		/* For skb_aggr, do not wake up tx queue */
		goto done;

	atomic_dec(&adapter->tx_pending);

	index = mwifiex_1d_to_wmm_queue[skb->priority];
	if (atomic_dec_return(&priv->wmm_tx_pending[index]) < LOW_TX_PENDING) {
		txq = netdev_get_tx_queue(priv->netdev, index);
		if (netif_tx_queue_stopped(txq)) {
			netif_tx_wake_queue(txq);
			dev_dbg(adapter->dev, "wake queue: %d\n", index);
		}
	}
done:
	dev_kfree_skb_any(skb);

	return 0;
}
EXPORT_SYMBOL_GPL(mwifiex_write_data_complete);