drivers/net/wireless/marvell/libertas/tx.c

Source file repositories/reference/linux-study-clean/drivers/net/wireless/marvell/libertas/tx.c

File Facts

System
Linux kernel
Corpus path
drivers/net/wireless/marvell/libertas/tx.c
Extension
.c
Size
5528 bytes
Lines
207
Domain
Driver Families
Bucket
drivers/net
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/*
 * This file contains the handling of TX in wlan driver.
 */
#include <linux/hardirq.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/sched.h>
#include <linux/export.h>
#include <net/cfg80211.h>

#include "host.h"
#include "radiotap.h"
#include "decl.h"
#include "defs.h"
#include "dev.h"
#include "mesh.h"

/**
 * convert_radiotap_rate_to_mv - converts Tx/Rx rates from IEEE80211_RADIOTAP_RATE
 * units (500 Kb/s) into Marvell WLAN format (see Table 8 in Section 3.2.1)
 *
 * @rate:	Input rate
 * returns:	Output Rate (0 if invalid)
 */
static u32 convert_radiotap_rate_to_mv(u8 rate)
{
	switch (rate) {
	case 2:		/*   1 Mbps */
		return 0 | (1 << 4);
	case 4:		/*   2 Mbps */
		return 1 | (1 << 4);
	case 11:		/* 5.5 Mbps */
		return 2 | (1 << 4);
	case 22:		/*  11 Mbps */
		return 3 | (1 << 4);
	case 12:		/*   6 Mbps */
		return 4 | (1 << 4);
	case 18:		/*   9 Mbps */
		return 5 | (1 << 4);
	case 24:		/*  12 Mbps */
		return 6 | (1 << 4);
	case 36:		/*  18 Mbps */
		return 7 | (1 << 4);
	case 48:		/*  24 Mbps */
		return 8 | (1 << 4);
	case 72:		/*  36 Mbps */
		return 9 | (1 << 4);
	case 96:		/*  48 Mbps */
		return 10 | (1 << 4);
	case 108:		/*  54 Mbps */
		return 11 | (1 << 4);
	}
	return 0;
}

/**
 * lbs_hard_start_xmit - checks the conditions and sends packet to IF
 * layer if everything is ok
 *
 * @skb:	A pointer to skb which includes TX packet
 * @dev:	A pointer to the &struct net_device
 * returns:	0 or -1
 */
netdev_tx_t lbs_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	unsigned long flags;
	struct lbs_private *priv = dev->ml_priv;
	struct txpd *txpd;
	char *p802x_hdr;
	uint16_t pkt_len;
	netdev_tx_t ret = NETDEV_TX_OK;

	/* We need to protect against the queues being restarted before
	   we get round to stopping them */
	spin_lock_irqsave(&priv->driver_lock, flags);

	if (priv->surpriseremoved)
		goto free;

	if (!skb->len || (skb->len > MRVDRV_ETH_TX_PACKET_BUFFER_SIZE)) {
		lbs_deb_tx("tx err: skb length %d 0 or > %zd\n",
		       skb->len, MRVDRV_ETH_TX_PACKET_BUFFER_SIZE);
		/* We'll never manage to send this one; drop it and return 'OK' */

		dev->stats.tx_dropped++;
		dev->stats.tx_errors++;
		goto free;
	}

Annotation

Implementation Notes