atmel.c

linux-2.4.29操作系统的源码

	
	if (priv->do_rx_crc) {
		u32 netcrc;
		crc = crc32_le(crc, skbp + 12, msdu_size);
		atmel_copy_to_host(priv->dev, (void *)&netcrc, rx_packet_loc + 30 + msdu_size, 4);
		if ((crc ^ 0xffffffff) != netcrc) {
			priv->stats.rx_crc_errors++;
			dev_kfree_skb(skb);
			return;
		}
	}
	
	memcpy(skbp, header->addr1, 6); /* destination address */
	if (le16_to_cpu(header->frame_ctl) & IEEE802_11_FCTL_FROMDS) 
		memcpy(&skbp[6], header->addr3, 6);
	else
		memcpy(&skbp[6], header->addr2, 6); /* source address */
	
	priv->dev->last_rx=jiffies;
	skb->dev = priv->dev;
	skb->protocol = eth_type_trans(skb, priv->dev);
	skb->ip_summed = CHECKSUM_NONE;	
	netif_rx(skb);
	priv->stats.rx_bytes += 12 + msdu_size;
	priv->stats.rx_packets++;
}

/* Test to see if the packet in card memory at packet_loc has a valid CRC
   It doesn't matter that this is slow: it is only used to proble the first few packets. */
static int probe_crc(struct atmel_private *priv, u16 packet_loc, u16 msdu_size)
{
	int i = msdu_size - 4;
	u32 netcrc, crc = 0xffffffff;

	if (msdu_size < 4)
		return 0;

	atmel_copy_to_host(priv->dev, (void *)&netcrc, packet_loc + i, 4);
	
	atmel_writeAR(priv->dev, packet_loc);
	while (i--) {
		u8 octet = atmel_read8(priv->dev, DR);
		crc = crc32_le(crc, &octet, 1);
	}

	return (crc ^ 0xffffffff) == netcrc;
}

static void frag_rx_path(struct atmel_private *priv, struct ieee802_11_hdr *header, 
			 u16 msdu_size, u16 rx_packet_loc, u32 crc, u16 seq_no, u8 frag_no, int more_frags)
{
	u8 mac4[6]; 
	u8 source[6];
	struct sk_buff *skb;

	if (le16_to_cpu(header->frame_ctl) & IEEE802_11_FCTL_FROMDS) 
		memcpy(source, header->addr3, 6);
	else
		memcpy(source, header->addr2, 6); 
	
	rx_packet_loc += 24; /* skip header */
	
	if (priv->do_rx_crc)
		msdu_size -= 4;

	if (frag_no == 0) { /* first fragment */
		atmel_copy_to_host(priv->dev, mac4, rx_packet_loc, 6);
		msdu_size -= 6;
		rx_packet_loc += 6;

		if (priv->do_rx_crc) 
			crc = crc32_le(crc, mac4, 6);
	       
		priv->frag_seq = seq_no;
		priv->frag_no = 1;
		priv->frag_len = msdu_size;
		memcpy(priv->frag_source, source, 6); 
		memcpy(&priv->rx_buf[6], source, 6);
		memcpy(priv->rx_buf, header->addr1, 6);
				
		atmel_copy_to_host(priv->dev, &priv->rx_buf[12], rx_packet_loc, msdu_size);

		if (priv->do_rx_crc) {
			u32 netcrc;
			crc = crc32_le(crc, &priv->rx_buf[12], msdu_size);
			atmel_copy_to_host(priv->dev, (void *)&netcrc, rx_packet_loc + msdu_size, 4);
			if ((crc ^ 0xffffffff) != netcrc) {
				priv->stats.rx_crc_errors++;
				memset(priv->frag_source, 0xff, 6);
			}
		}
		
	} else if (priv->frag_no == frag_no &&
		   priv->frag_seq == seq_no &&
		   memcmp(priv->frag_source, source, 6) == 0) {
		
		atmel_copy_to_host(priv->dev, &priv->rx_buf[12 + priv->frag_len], 
				   rx_packet_loc, msdu_size);
		if (priv->do_rx_crc) {
			u32 netcrc;
			crc = crc32_le(crc, 
				       &priv->rx_buf[12 + priv->frag_len], 
				       msdu_size);
			atmel_copy_to_host(priv->dev, (void *)&netcrc, rx_packet_loc + msdu_size, 4);
			if ((crc ^ 0xffffffff) != netcrc) {
				priv->stats.rx_crc_errors++;
				memset(priv->frag_source, 0xff, 6);
				more_frags = 1; /* don't send broken assembly */
			}
		}
		
		priv->frag_len += msdu_size;
		priv->frag_no++;

		if (!more_frags) { /* last one */
			memset(priv->frag_source, 0xff, 6);
			if (!(skb = dev_alloc_skb(priv->frag_len + 14))) {
				priv->stats.rx_dropped++;
			} else {
				skb_reserve(skb, 2);
				memcpy(skb_put(skb, priv->frag_len + 12), 
				       priv->rx_buf,
				       priv->frag_len + 12);
				priv->dev->last_rx = jiffies;
				skb->dev = priv->dev;
				skb->protocol = eth_type_trans(skb, priv->dev);
				skb->ip_summed = CHECKSUM_NONE;	
				netif_rx(skb);
				priv->stats.rx_bytes += priv->frag_len + 12;
				priv->stats.rx_packets++;
			}
		}
		
	} else
		priv->wstats.discard.fragment++;
}
		
static void rx_done_irq(struct atmel_private *priv)
{
	int i;
	struct ieee802_11_hdr header;
	
	for (i = 0; 
	     atmel_rmem8(priv, atmel_rx(priv, RX_DESC_FLAGS_OFFSET, priv->rx_desc_head)) == RX_DESC_FLAG_VALID &&
		     i < priv->host_info.rx_desc_count;
	     i++) {
				
		u16 msdu_size, rx_packet_loc, frame_ctl, seq_control;
		u8 status = atmel_rmem8(priv, atmel_rx(priv, RX_DESC_STATUS_OFFSET, priv->rx_desc_head));
		u32 crc = 0xffffffff;
		
		if (status != RX_STATUS_SUCCESS) {
			if (status == 0xc1) /* determined by experiment */
				priv->wstats.discard.nwid++;
			else
				priv->stats.rx_errors++; 
			goto next;
		}

		msdu_size = atmel_rmem16(priv, atmel_rx(priv, RX_DESC_MSDU_SIZE_OFFSET, priv->rx_desc_head));
		rx_packet_loc = atmel_rmem16(priv, atmel_rx(priv, RX_DESC_MSDU_POS_OFFSET, priv->rx_desc_head));
		
		if (msdu_size < 30) {
			priv->stats.rx_errors++; 
			goto next;
		}
		
		/* Get header as far as end of seq_ctl */
		atmel_copy_to_host(priv->dev, (char *)&header, rx_packet_loc, 24);
		frame_ctl = le16_to_cpu(header.frame_ctl);
		seq_control = le16_to_cpu(header.seq_ctl);

		/* probe for CRC use here if needed  once five packets have arrived with
		   the same crc status, we assume we know what's happening and stop probing */
		if (priv->probe_crc) {
			if (!priv->wep.wep_is_on || !(frame_ctl & IEEE802_11_FCTL_WEP)) {
				priv->do_rx_crc = probe_crc(priv, rx_packet_loc, msdu_size);
			} else {
				priv->do_rx_crc = probe_crc(priv, rx_packet_loc + 24, msdu_size - 24);
			}
			if (priv->do_rx_crc) {
				if (priv->crc_ok_cnt++ > 5)
					priv->probe_crc = 0;
			} else {
				if (priv->crc_ko_cnt++ > 5)
					priv->probe_crc = 0;
			}
		}
		    
		/* don't CRC header when WEP in use */
		if (priv->do_rx_crc && (!priv->wep.wep_is_on || !(frame_ctl & IEEE802_11_FCTL_WEP))) {
			crc = crc32_le(0xffffffff, (unsigned char *)&header, 24);
		}
		msdu_size -= 24; /* header */

		if ((frame_ctl & IEEE802_11_FCTL_FTYPE) == IEEE802_11_FTYPE_DATA) { 
			
			int more_fragments = frame_ctl & IEEE802_11_FCTL_MOREFRAGS;
			u8 packet_fragment_no = seq_control & IEEE802_11_SCTL_FRAG;
			u16 packet_sequence_no = (seq_control & IEEE802_11_SCTL_SEQ) >> 4;
			
			if (!more_fragments && packet_fragment_no == 0 ) {
				fast_rx_path(priv, &header, msdu_size, rx_packet_loc, crc);
			} else {
				frag_rx_path(priv, &header, msdu_size, rx_packet_loc, crc,
					     packet_sequence_no, packet_fragment_no, more_fragments);
			}
		}
		
		if ((frame_ctl & IEEE802_11_FCTL_FTYPE) == IEEE802_11_FTYPE_MGMT) {
			/* copy rest of packet into buffer */
			atmel_copy_to_host(priv->dev, (unsigned char *)&priv->rx_buf, rx_packet_loc + 24, msdu_size);
			
			/* we use the same buffer for frag reassembly and control packets */
			memset(priv->frag_source, 0xff, 6);
			
			if (priv->do_rx_crc) {
				/* last 4 octets is crc */
				msdu_size -= 4;
				crc = crc32_le(crc, (unsigned char *)&priv->rx_buf, msdu_size);
				if ((crc ^ 0xffffffff) != (*((u32 *)&priv->rx_buf[msdu_size]))) {
					priv->stats.rx_crc_errors++;
					goto next;
				}
			}

			atmel_management_frame(priv, &header, msdu_size,
					       atmel_rmem8(priv, atmel_rx(priv, RX_DESC_RSSI_OFFSET, priv->rx_desc_head)));
		} 

	next:
		/* release descriptor */
		atmel_wmem8(priv, atmel_rx(priv, RX_DESC_FLAGS_OFFSET, priv->rx_desc_head), RX_DESC_FLAG_CONSUMED);  
		
		if (priv->rx_desc_head < (priv->host_info.rx_desc_count - 1))
			priv->rx_desc_head++;					
		else
			priv->rx_desc_head = 0;
	}
}	

static void reset_irq_status(struct atmel_private *priv, u8 mask)
{
	u8 isr;
	
	atmel_lock_mac(priv);
	isr = atmel_rmem8(priv, atmel_hi(priv, IFACE_INT_STATUS_OFFSET));
	isr ^= mask;
	atmel_wmem8(priv, atmel_hi(priv, IFACE_INT_STATUS_OFFSET), isr);
	atmel_wmem8(priv, atmel_hi(priv, IFACE_LOCKOUT_MAC_OFFSET), 0);
}

static void service_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	struct net_device *dev = (struct net_device *) dev_id;
	struct atmel_private *priv = (struct atmel_private *) dev->priv;
	u8 isr;
	
	if (priv->card && priv->present_callback && 
	    !(*priv->present_callback)(priv->card))
		return;
     	
	atmel_clear_gcr(dev, GCR_ENINT); /* disable interrupts */
	
	while (1) {
		if (!atmel_lock_mac(priv)) {
			printk(KERN_ALERT "%s: MAC gone away in ISR.\n", dev->name);
			/* bad things - don't re-enable interrupts */
			return;
		}
			
		isr = atmel_rmem8(priv, atmel_hi(priv, IFACE_INT_STATUS_OFFSET));
		atmel_wmem8(priv, atmel_hi(priv, IFACE_LOCKOUT_MAC_OFFSET), 0);
		if (isr)
			atmel_set_gcr(dev, GCR_ACKINT); /* acknowledge interrupt */
		else
			break; /* no pending irqs */

		if (isr & ISR_OUT_OF_RANGE) {
			reset_irq_status(priv, ISR_OUT_OF_RANGE);
			if(priv->operating_mode == IW_MODE_INFRA && 
			   priv->station_state == STATION_STATE_READY) {
				priv->station_is_associated = 0;
				atmel_scan(priv, 1);
			}
		} else if (isr & ISR_RxCOMPLETE) {
			reset_irq_status(priv, ISR_RxCOMPLETE);
			rx_done_irq(priv); 
		} else if (isr & ISR_TxCOMPLETE) {
			reset_irq_status(priv, ISR_TxCOMPLETE);
			tx_done_irq(priv); 
		} else if (isr & ISR_RxFRAMELOST) {
			reset_irq_status(priv, ISR_RxFRAMELOST);
			priv->wstats.discard.misc++;
			rx_done_irq(priv);
		} else if (isr & ISR_FATAL_ERROR) {
			reset_irq_status(priv, ISR_FATAL_ERROR);
			printk(KERN_ALERT "%s: *** FATAL error interrupt ***\n", dev->name);
			atmel_enter_state(priv, STATION_STATE_MGMT_ERROR);
		} else if (isr & ISR_COMMAND_COMPLETE) {
			reset_irq_status(priv, ISR_COMMAND_COMPLETE);
			atmel_command_irq(priv);	
		} else if (isr & ISR_IBSS_MERGE) {
			reset_irq_status(priv, ISR_IBSS_MERGE);
			atmel_get_mib(priv, Mac_Mgmt_Mib_Type, MAC_MGMT_MIB_CUR_BSSID_POS, 
				      priv->CurrentBSSID, 6);
		} else if (isr & ISR_GENERIC_IRQ) {
			reset_irq_status(priv, ISR_GENERIC_IRQ);
			printk(KERN_INFO "%s: Generic_irq recieved.\n", dev->name);
		}
	}	

	atmel_set_gcr(dev, GCR_ENINT); /* enable interrupts */
	return;
}


static struct net_device_stats *atmel_get_stats (struct net_device *dev)
{
	struct atmel_private *priv = (struct atmel_private *)dev->priv;
	return &priv->stats;
}

static struct iw_statistics *atmel_get_wireless_stats (struct net_device *dev)
{
	struct atmel_private *priv = (struct atmel_private *)dev->priv;

	/* update the link quality here in case we are seeing no beacons 
	   at all to drive the process */
	atmel_smooth_qual(priv);
	
	priv->wstats.status = priv->station_state;

	if (priv->operating_mode == IW_MODE_INFRA) {
		if (priv->station_state != STATION_STATE_READY) {
			priv->wstats.qual.qual = 0;
			priv->wstats.qual.level	= 0;
		}
		priv->wstats.qual.noise = 0;
		priv->wstats.qual.updated = 7;
	} else {
		// Quality levels cannot be determined in ad-hoc mode,
		// because we can 'hear' more than one remote station.
		priv->wstats.qual.qual = 0;
		priv->wstats.qual.level	= 0;
		priv->wstats.qual.noise	= 0;
		priv->wstats.qual.updated = 0;
		priv->wstats.miss.beacon = 0;
	}
	
	return (&priv->wstats);
}

static int atmel_change_mtu(struct net_device *dev, int new_mtu)
{
        if ((new_mtu < 68) || (new_mtu > 2312))
                return -EINVAL;
        dev->mtu = new_mtu;
        return 0;
}

static int atmel_set_mac_address(struct net_device *dev, void *p)
{
	struct sockaddr *addr = p;
        
        memcpy (dev->dev_addr, addr->sa_data, dev->addr_len);
	reset_atmel_card(dev);
	return 0;
}

static int atmel_open (struct net_device *dev)
{
	struct atmel_private *priv = (struct atmel_private *) dev->priv;
	priv->station_state = STATION_STATE_INITIALIZING;
	if (!reset_atmel_card(dev)) {
		priv->station_state = STATION_STATE_DOWN;
		return -EAGAIN;
	}
	return 0;
}

static int atmel_close (struct net_device *dev)
{
	struct atmel_private *priv = (struct atmel_private *) dev->priv;
		
	if (netif_running(dev))
		netif_stop_queue(dev);
	
	priv->station_state = STATION_STATE_DOWN;
	if (priv->bus_type == BUS_TYPE_PCCARD) 
		atmel_write16(dev, GCR, 0x0060);
	atmel_write16(dev, GCR, 0x0040);
	return 0;
}

static int atmel_proc_output (char *buf, struct atmel_private *priv)
{
	char *p = buf;
	char *s, *r, *c;
	
	p += sprintf(p, "Driver version:\t\t%d.%d\n", DRIVER_MAJOR, DRIVER_MINOR);
	
	if (priv->station_state != STATION_STATE_DOWN) {
		p += sprintf(p, "Firmware version:\t%d.%d build %d ", 
			     priv->host_info.major_version,
			     priv->host_info.minor_version,
			     priv->host_info.build_version);
		
		if (priv->card_type != CARD_TYPE_EEPROM) 
			p += sprintf(p, "[built-in]\n");
		else if (priv->firmware) 
			p += sprintf(p, "[%s loaded by host]\n", priv->firmware_id);
		else
			p += sprintf(p, "[%s loaded by hotplug]\n", priv->firmware_id);
		
		switch(priv->card_type) {
		case CARD_TYPE_PARALLEL_FLASH: c = "Parallel flash"; break;
		case CARD_TYPE_SPI_FLASH: c = "SPI flash\n"; break;
		case CARD_TYPE_EEPROM: c = "EEPROM"; break;
		default: c = "<unknown>";
		}

		switch (priv->reg_domain) {
		case REG_DOMAIN_FCC: r = "USA"; break;