zd1201.c

底层驱动开发

		/* Skip the 4 bytes header (RID length and RID) */
		if(i == 0) {
			pdata += 8;
			actual_length -= 8;
		}
		else {
			pdata += 4;
			actual_length -= 4;
		}
		
		memcpy(riddata, pdata, actual_length);
		riddata += actual_length;
		pdata += actual_length;
		length -= 64;
		i++;
	} while (length > 0);

	return 0;
}

/*
 *	resreq:
 *		byte	type
 *		byte	sequence
 *		u16	reserved
 *		byte	data[12]
 *	total: 16
 */
static int zd1201_setconfig(struct zd1201 *zd, int rid, void *buf, int len, int wait)
{
	int err;
	unsigned char *request;
	int reqlen;
	char seq=0;
	struct urb *urb;
	unsigned int gfp_mask = wait ? GFP_NOIO : GFP_ATOMIC;

	len += 4;			/* first 4 are for header */

	zd->rxdatas = 0;
	zd->rxlen = 0;
	for (seq=0; len > 0; seq++) {
		request = kmalloc(16, gfp_mask);
		if (!request)
			return -ENOMEM;
		urb = usb_alloc_urb(0, gfp_mask);
		if (!urb) {
			kfree(request);
			return -ENOMEM;
		}
		memset(request, 0, 16);
		reqlen = len>12 ? 12 : len;
		request[0] = ZD1201_USB_RESREQ;
		request[1] = seq;
		request[2] = 0;
		request[3] = 0;
		if (request[1] == 0) {
			/* add header */
			*(__le16*)&request[4] = cpu_to_le16((len-2+1)/2);
			*(__le16*)&request[6] = cpu_to_le16(rid);
			memcpy(request+8, buf, reqlen-4);
			buf += reqlen-4;
		} else {
			memcpy(request+4, buf, reqlen);
			buf += reqlen;
		}

		len -= reqlen;

		usb_fill_bulk_urb(urb, zd->usb, usb_sndbulkpipe(zd->usb,
		    zd->endp_out2), request, 16, zd1201_usbfree, zd);
		err = usb_submit_urb(urb, gfp_mask);
		if (err)
			goto err;
	}

	request = kmalloc(16, gfp_mask);
	if (!request)
		return -ENOMEM;
	urb = usb_alloc_urb(0, gfp_mask);
	if (!urb) {
		kfree(request);
		return -ENOMEM;
	}
	*((__le32*)request) = cpu_to_le32(ZD1201_USB_CMDREQ);
	*((__le16*)&request[4]) = 
	    cpu_to_le16(ZD1201_CMDCODE_ACCESS|ZD1201_ACCESSBIT);
	*((__le16*)&request[6]) = cpu_to_le16(rid);
	*((__le16*)&request[8]) = cpu_to_le16(0);
	*((__le16*)&request[10]) = cpu_to_le16(0);
	usb_fill_bulk_urb(urb, zd->usb, usb_sndbulkpipe(zd->usb, zd->endp_out2),
	     request, 16, zd1201_usbfree, zd);
	err = usb_submit_urb(urb, gfp_mask);
	if (err)
		goto err;
	
	if (wait) {
		wait_event_interruptible(zd->rxdataq, zd->rxdatas);
		if (!zd->rxlen || le16_to_cpu(*(__le16*)&zd->rxdata[6]) != rid) {
			dev_dbg(&zd->usb->dev, "wrong or no RID received\n");
		}
	}

	return 0;
err:
	kfree(request);
	usb_free_urb(urb);
	return err;
}

static inline int zd1201_getconfig16(struct zd1201 *zd, int rid, short *val)
{
	int err;
	__le16 zdval;

	err = zd1201_getconfig(zd, rid, &zdval, sizeof(__le16));
	if (err)
		return err;
	*val = le16_to_cpu(zdval);
	return 0;
}

static inline int zd1201_setconfig16(struct zd1201 *zd, int rid, short val)
{
	__le16 zdval = cpu_to_le16(val);
	return (zd1201_setconfig(zd, rid, &zdval, sizeof(__le16), 1));
}

static int zd1201_drvr_start(struct zd1201 *zd)
{
	int err, i;
	short max;
	__le16 zdmax;
	unsigned char *buffer;
	
	buffer = kmalloc(ZD1201_RXSIZE, GFP_KERNEL);
	if (!buffer)
		return -ENOMEM;
	memset(buffer, 0, ZD1201_RXSIZE);

	usb_fill_bulk_urb(zd->rx_urb, zd->usb, 
	    usb_rcvbulkpipe(zd->usb, zd->endp_in), buffer, ZD1201_RXSIZE,
	    zd1201_usbrx, zd);

	err = usb_submit_urb(zd->rx_urb, GFP_KERNEL);
	if (err)
		goto err_buffer;
	
	err = zd1201_docmd(zd, ZD1201_CMDCODE_INIT, 0, 0, 0);
	if (err)
		goto err_urb;

	err = zd1201_getconfig(zd, ZD1201_RID_CNFMAXTXBUFFERNUMBER, &zdmax,
	    sizeof(__le16));
	if (err)
		goto err_urb;

	max = le16_to_cpu(zdmax);
	for (i=0; i<max; i++) {
		err = zd1201_docmd(zd, ZD1201_CMDCODE_ALLOC, 1514, 0, 0);
		if (err)
			goto err_urb;
	}

	return 0;

err_urb:
	usb_kill_urb(zd->rx_urb);
	return err;
err_buffer:
	kfree(buffer);
	return err;
}

/*	Magic alert: The firmware doesn't seem to like the MAC state being
 *	toggled in promisc (aka monitor) mode.
 *	(It works a number of times, but will halt eventually)
 *	So we turn it of before disabling and on after enabling if needed.
 */
static int zd1201_enable(struct zd1201 *zd)
{
	int err;

	if (zd->mac_enabled)
		return 0;

	err = zd1201_docmd(zd, ZD1201_CMDCODE_ENABLE, 0, 0, 0);
	if (!err)
		zd->mac_enabled = 1;

	if (zd->monitor)
		err = zd1201_setconfig16(zd, ZD1201_RID_PROMISCUOUSMODE, 1);

	return err;
}

static int zd1201_disable(struct zd1201 *zd)
{
	int err;
	
	if (!zd->mac_enabled)
		return 0;
	if (zd->monitor) {
		err = zd1201_setconfig16(zd, ZD1201_RID_PROMISCUOUSMODE, 0);
		if (err)
			return err;
	}

	err = zd1201_docmd(zd, ZD1201_CMDCODE_DISABLE, 0, 0, 0);
	if (!err)
		zd->mac_enabled = 0;
	return err;
}

static int zd1201_mac_reset(struct zd1201 *zd)
{
	if (!zd->mac_enabled)
		return 0;
	zd1201_disable(zd);
	return zd1201_enable(zd);
}

static int zd1201_join(struct zd1201 *zd, char *essid, int essidlen)
{
	int err, val;
	char buf[IW_ESSID_MAX_SIZE+2];

	err = zd1201_disable(zd);
	if (err)
		return err;

	val = ZD1201_CNFAUTHENTICATION_OPENSYSTEM;
	val |= ZD1201_CNFAUTHENTICATION_SHAREDKEY;
	err = zd1201_setconfig16(zd, ZD1201_RID_CNFAUTHENTICATION, val);
	if (err)
		return err;

	*(__le16 *)buf = cpu_to_le16(essidlen);
	memcpy(buf+2, essid, essidlen);
	if (!zd->ap) {	/* Normal station */
		err = zd1201_setconfig(zd, ZD1201_RID_CNFDESIREDSSID, buf,
		    IW_ESSID_MAX_SIZE+2, 1);
		if (err)
			return err;
	} else {	/* AP */
		err = zd1201_setconfig(zd, ZD1201_RID_CNFOWNSSID, buf,
		    IW_ESSID_MAX_SIZE+2, 1);
		if (err)
			return err;
	}

	err = zd1201_setconfig(zd, ZD1201_RID_CNFOWNMACADDR, 
	    zd->dev->dev_addr, zd->dev->addr_len, 1);
	if (err)
		return err;

	err = zd1201_enable(zd);
	if (err)
		return err;

	msleep(100);
	return 0;
}

static int zd1201_net_open(struct net_device *dev)
{
	struct zd1201 *zd = (struct zd1201 *)dev->priv;

	/* Start MAC with wildcard if no essid set */
	if (!zd->mac_enabled)
		zd1201_join(zd, zd->essid, zd->essidlen);
	netif_start_queue(dev);

	return 0;
}

static int zd1201_net_stop(struct net_device *dev)
{
	netif_stop_queue(dev);
	
	return 0;
}

/*
	RFC 1042 encapsulates Ethernet frames in 802.11 frames
	by prefixing them with 0xaa, 0xaa, 0x03) followed by a SNAP OID of 0
	(0x00, 0x00, 0x00). Zd requires an additional padding, copy
	of ethernet addresses, length of the standard RFC 1042 packet
	and a command byte (which is nul for tx).
	
	tx frame (from Wlan NG):
	RFC 1042:
		llc		0xAA 0xAA 0x03 (802.2 LLC)
		snap		0x00 0x00 0x00 (Ethernet encapsulated)
		type		2 bytes, Ethernet type field
		payload		(minus eth header)
	Zydas specific:
		padding		1B if (skb->len+8+1)%64==0
		Eth MAC addr	12 bytes, Ethernet MAC addresses
		length		2 bytes, RFC 1042 packet length 
				(llc+snap+type+payload)
		zd		1 null byte, zd1201 packet type
 */
static int zd1201_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct zd1201 *zd = (struct zd1201 *)dev->priv;
	unsigned char *txbuf = zd->txdata;
	int txbuflen, pad = 0, err;
	struct urb *urb = zd->tx_urb;

	if (!zd->mac_enabled || zd->monitor) {
		zd->stats.tx_dropped++;
		kfree_skb(skb);
		return 0;
	}
	netif_stop_queue(dev);

	txbuflen = skb->len + 8 + 1;
	if (txbuflen%64 == 0) {
		pad = 1;
		txbuflen++;
	}
	txbuf[0] = 0xAA;
	txbuf[1] = 0xAA;
	txbuf[2] = 0x03;
	txbuf[3] = 0x00;	/* rfc1042 */
	txbuf[4] = 0x00;
	txbuf[5] = 0x00;

	memcpy(txbuf+6, skb->data+12, skb->len-12);
	if (pad)
		txbuf[skb->len-12+6]=0;
	memcpy(txbuf+skb->len-12+6+pad, skb->data, 12);
	*(__be16*)&txbuf[skb->len+6+pad] = htons(skb->len-12+6);
	txbuf[txbuflen-1] = 0;

	usb_fill_bulk_urb(urb, zd->usb, usb_sndbulkpipe(zd->usb, zd->endp_out),
	    txbuf, txbuflen, zd1201_usbtx, zd);

	err = usb_submit_urb(zd->tx_urb, GFP_ATOMIC);
	if (err) {
		zd->stats.tx_errors++;
		netif_start_queue(dev);
		return err;
	}
	zd->stats.tx_packets++;
	zd->stats.tx_bytes += skb->len;
	dev->trans_start = jiffies;
	kfree_skb(skb);

	return 0;
}

static void zd1201_tx_timeout(struct net_device *dev)
{
	struct zd1201 *zd = (struct zd1201 *)dev->priv;

	if (!zd)
		return;
	dev_warn(&zd->usb->dev, "%s: TX timeout, shooting down urb\n",
	    dev->name);
	usb_unlink_urb(zd->tx_urb);
	zd->stats.tx_errors++;
	/* Restart the timeout to quiet the watchdog: */
	dev->trans_start = jiffies;
}

static int zd1201_set_mac_address(struct net_device *dev, void *p)
{
	struct sockaddr *addr = p;
	struct zd1201 *zd = (struct zd1201 *)dev->priv;
	int err;

	if (!zd)
		return -ENODEV;

	err = zd1201_setconfig(zd, ZD1201_RID_CNFOWNMACADDR, 
	    addr->sa_data, dev->addr_len, 1);
	if (err)
		return err;
	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);

	return zd1201_mac_reset(zd);
}

static struct net_device_stats *zd1201_get_stats(struct net_device *dev)
{
	struct zd1201 *zd = (struct zd1201 *)dev->priv;

	return &zd->stats;
}

static struct iw_statistics *zd1201_get_wireless_stats(struct net_device *dev)
{
	struct zd1201 *zd = (struct zd1201 *)dev->priv;

	return &zd->iwstats;
}

static void zd1201_set_multicast(struct net_device *dev)
{
	struct zd1201 *zd = (struct zd1201 *)dev->priv;
	struct dev_mc_list *mc = dev->mc_list;
	unsigned char reqbuf[ETH_ALEN*ZD1201_MAXMULTI];
	int i;

	if (dev->mc_count > ZD1201_MAXMULTI)
		return;

	for (i=0; i<dev->mc_count; i++) {
		memcpy(reqbuf+i*ETH_ALEN, mc->dmi_addr, ETH_ALEN);
		mc = mc->next;
	}
	zd1201_setconfig(zd, ZD1201_RID_CNFGROUPADDRESS, reqbuf,
	    dev->mc_count*ETH_ALEN, 0);
	
}

static int zd1201_config_commit(struct net_device *dev, 
    struct iw_request_info *info, struct iw_point *data, char *essid)
{
	struct zd1201 *zd = (struct zd1201 *)dev->priv;

	return zd1201_mac_reset(zd);
}

static int zd1201_get_name(struct net_device *dev,
    struct iw_request_info *info, char *name, char *extra)
{
	strcpy(name, "IEEE 802.11b");

	return 0;
}

static int zd1201_set_freq(struct net_device *dev,
    struct iw_request_info *info, struct iw_freq *freq, char *extra)
{
	struct zd1201 *zd = (struct zd1201 *)dev->priv;
	short channel = 0;
	int err;

	if (freq->e == 0)
		channel = freq->m;
	else {
		if (freq->m >= 2482)
			channel = 14;
		if (freq->m >= 2407)
			channel = (freq->m-2407)/5;
	}

	err = zd1201_setconfig16(zd, ZD1201_RID_CNFOWNCHANNEL, channel);
	if (err)
		return err;

	zd1201_mac_reset(zd);

	return 0;
}

static int zd1201_get_freq(struct net_device *dev,
    struct iw_request_info *info, struct iw_freq *freq, char *extra)
{
	struct zd1201 *zd = (struct zd1201 *)dev->priv;
	short channel;
	int err;

	err = zd1201_getconfig16(zd, ZD1201_RID_CNFOWNCHANNEL, &channel);
	if (err)
		return err;
	freq->e = 0;
	freq->m = channel;

	return 0;
}

static int zd1201_set_mode(struct net_device *dev,
    struct iw_request_info *info, __u32 *mode, char *extra)
{
	struct zd1201 *zd = (struct zd1201 *)dev->priv;
	short porttype, monitor = 0;
	unsigned char buffer[IW_ESSID_MAX_SIZE+2];
	int err;

	if (zd->ap) {
		if (*mode != IW_MODE_MASTER)
			return -EINVAL;