[linux-2.6-block.git] / drivers / net / usb / lg-vl600.c

/*
 * Ethernet interface part of the LG VL600 LTE modem (4G dongle)
 *
 * Copyright (C) 2011 Intel Corporation
 * Author: Andrzej Zaborowski <balrogg@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/mii.h>
#include <linux/usb.h>
#include <linux/usb/cdc.h>
#include <linux/usb/usbnet.h>
#include <linux/if_ether.h>
#include <linux/if_arp.h>
#include <linux/inetdevice.h>

/*
 * The device has a CDC ACM port for modem control (it claims to be
 * CDC ACM anyway) and a CDC Ethernet port for actual network data.
 * It will however ignore data on both ports that is not encapsulated
 * in a specific way, any data returned is also encapsulated the same
 * way.  The headers don't seem to follow any popular standard.
 *
 * This driver adds and strips these headers from the ethernet frames
 * sent/received from the CDC Ethernet port.  The proprietary header
 * replaces the standard ethernet header in a packet so only actual
 * ethernet frames are allowed.  The headers allow some form of
 * multiplexing by using non standard values of the .h_proto field.
 * Windows/Mac drivers do send a couple of such frames to the device
 * during initialisation, with protocol set to 0x0906 or 0x0b06 and (what
 * seems to be) a flag in the .dummy_flags.  This doesn't seem necessary
 * for modem operation but can possibly be used for GPS or other funcitons.
 */

struct vl600_frame_hdr {
	__le32 len;
	__le32 serial;
	__le32 pkt_cnt;
	__le32 dummy_flags;
	__le32 dummy;
	__le32 magic;
} __attribute__((packed));

struct vl600_pkt_hdr {
	__le32 dummy[2];
	__le32 len;
	__be16 h_proto;
} __attribute__((packed));

struct vl600_state {
	struct sk_buff *current_rx_buf;
};

static int vl600_bind(struct usbnet *dev, struct usb_interface *intf)
{
	int ret;
	struct vl600_state *s = kzalloc(sizeof(struct vl600_state), GFP_KERNEL);

	if (!s)
		return -ENOMEM;

	ret = usbnet_cdc_bind(dev, intf);
	if (ret) {
		kfree(s);
		return ret;
	}

	dev->driver_priv = s;

	/* ARP packets don't go through, but they're also of no use.  The
	 * subnet has only two hosts anyway: us and the gateway / DHCP
	 * server (probably simulated by modem firmware or network operator)
	 * whose address changes everytime we connect to the intarwebz and
	 * who doesn't bother answering ARP requests either.  So hardware
	 * addresses have no meaning, the destination and the source of every
	 * packet depend only on whether it is on the IN or OUT endpoint.  */
	dev->net->flags |= IFF_NOARP;
	/* IPv6 NDP relies on multicast.  Enable it by default. */
	dev->net->flags |= IFF_MULTICAST;

	return ret;
}

static void vl600_unbind(struct usbnet *dev, struct usb_interface *intf)
{
	struct vl600_state *s = dev->driver_priv;

	if (s->current_rx_buf)
		dev_kfree_skb(s->current_rx_buf);

	kfree(s);

	return usbnet_cdc_unbind(dev, intf);
}

static int vl600_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
{
	struct vl600_frame_hdr *frame;
	struct vl600_pkt_hdr *packet;
	struct ethhdr *ethhdr;
	int packet_len, count;
	struct sk_buff *buf = skb;
	struct sk_buff *clone;
	struct vl600_state *s = dev->driver_priv;

	/* Frame lengths are generally 4B multiplies but every couple of
	 * hours there's an odd number of bytes sized yet correct frame,
	 * so don't require this.  */

	/* Allow a packet (or multiple packets batched together) to be
	 * split across many frames.  We don't allow a new batch to
	 * begin in the same frame another one is ending however, and no
	 * leading or trailing pad bytes.  */
	if (s->current_rx_buf) {
		frame = (struct vl600_frame_hdr *) s->current_rx_buf->data;
		if (skb->len + s->current_rx_buf->len >
				le32_to_cpup(&frame->len)) {
			netif_err(dev, ifup, dev->net, "Fragment too long\n");
			dev->net->stats.rx_length_errors++;
			goto error;
		}

		buf = s->current_rx_buf;
		memcpy(skb_put(buf, skb->len), skb->data, skb->len);
	} else if (skb->len < 4) {
		netif_err(dev, ifup, dev->net, "Frame too short\n");
		dev->net->stats.rx_length_errors++;
		goto error;
	}

	frame = (struct vl600_frame_hdr *) buf->data;
	/* NOTE: Should check that frame->magic == 0x53544448?
	 * Otherwise if we receive garbage at the beginning of the frame
	 * we may end up allocating a huge buffer and saving all the
	 * future incoming data into it.  */

	if (buf->len < sizeof(*frame) ||
			buf->len != le32_to_cpup(&frame->len)) {
		/* Save this fragment for later assembly */
		if (s->current_rx_buf)
			return 0;

		s->current_rx_buf = skb_copy_expand(skb, 0,
				le32_to_cpup(&frame->len), GFP_ATOMIC);
		if (!s->current_rx_buf) {
			netif_err(dev, ifup, dev->net, "Reserving %i bytes "
					"for packet assembly failed.\n",
					le32_to_cpup(&frame->len));
			dev->net->stats.rx_errors++;
		}

		return 0;
	}

	count = le32_to_cpup(&frame->pkt_cnt);

	skb_pull(buf, sizeof(*frame));

	while (count--) {
		if (buf->len < sizeof(*packet)) {
			netif_err(dev, ifup, dev->net, "Packet too short\n");
			goto error;
		}

		packet = (struct vl600_pkt_hdr *) buf->data;
		packet_len = sizeof(*packet) + le32_to_cpup(&packet->len);
		if (packet_len > buf->len) {
			netif_err(dev, ifup, dev->net,
					"Bad packet length stored in header\n");
			goto error;
		}

		/* Packet header is same size as the ethernet header
		 * (sizeof(*packet) == sizeof(*ethhdr)), additionally
		 * the h_proto field is in the same place so we just leave it
		 * alone and fill in the remaining fields.
		 */
		ethhdr = (struct ethhdr *) skb->data;
		if (be16_to_cpup(&ethhdr->h_proto) == ETH_P_ARP &&
				buf->len > 0x26) {
			/* Copy the addresses from packet contents */
			memcpy(ethhdr->h_source,
					&buf->data[sizeof(*ethhdr) + 0x8],
					ETH_ALEN);
			memcpy(ethhdr->h_dest,
					&buf->data[sizeof(*ethhdr) + 0x12],
					ETH_ALEN);
		} else {
			memset(ethhdr->h_source, 0, ETH_ALEN);
			memcpy(ethhdr->h_dest, dev->net->dev_addr, ETH_ALEN);

			/* Inbound IPv6 packets have an IPv4 ethertype (0x800)
			 * for some reason.  Peek at the L3 header to check
			 * for IPv6 packets, and set the ethertype to IPv6
			 * (0x86dd) so Linux can understand it.
			 */
			if ((buf->data[sizeof(*ethhdr)] & 0xf0) == 0x60)
				ethhdr->h_proto = __constant_htons(ETH_P_IPV6);
		}

		if (count) {
			/* Not the last packet in this batch */
			clone = skb_clone(buf, GFP_ATOMIC);
			if (!clone)
				goto error;

			skb_trim(clone, packet_len);
			usbnet_skb_return(dev, clone);

			skb_pull(buf, (packet_len + 3) & ~3);
		} else {
			skb_trim(buf, packet_len);

			if (s->current_rx_buf) {
				usbnet_skb_return(dev, buf);
				s->current_rx_buf = NULL;
				return 0;
			}

			return 1;
		}
	}

error:
	if (s->current_rx_buf) {
		dev_kfree_skb_any(s->current_rx_buf);
		s->current_rx_buf = NULL;
	}
	dev->net->stats.rx_errors++;
	return 0;
}

static struct sk_buff *vl600_tx_fixup(struct usbnet *dev,
		struct sk_buff *skb, gfp_t flags)
{
	struct sk_buff *ret;
	struct vl600_frame_hdr *frame;
	struct vl600_pkt_hdr *packet;
	static uint32_t serial = 1;
	int orig_len = skb->len - sizeof(struct ethhdr);
	int full_len = (skb->len + sizeof(struct vl600_frame_hdr) + 3) & ~3;

	frame = (struct vl600_frame_hdr *) skb->data;
	if (skb->len > sizeof(*frame) && skb->len == le32_to_cpup(&frame->len))
		return skb; /* Already encapsulated? */

	if (skb->len < sizeof(struct ethhdr))
		/* Drop, device can only deal with ethernet packets */
		return NULL;

	if (!skb_cloned(skb)) {
		int headroom = skb_headroom(skb);
		int tailroom = skb_tailroom(skb);

		if (tailroom >= full_len - skb->len - sizeof(*frame) &&
				headroom >= sizeof(*frame))
			/* There's enough head and tail room */
			goto encapsulate;

		if (headroom + tailroom + skb->len >= full_len) {
			/* There's enough total room, just readjust */
			skb->data = memmove(skb->head + sizeof(*frame),
					skb->data, skb->len);
			skb_set_tail_pointer(skb, skb->len);
			goto encapsulate;
		}
	}

	/* Alloc a new skb with the required size */
	ret = skb_copy_expand(skb, sizeof(struct vl600_frame_hdr), full_len -
			skb->len - sizeof(struct vl600_frame_hdr), flags);
	dev_kfree_skb_any(skb);
	if (!ret)
		return ret;
	skb = ret;

encapsulate:
	/* Packet header is same size as ethernet packet header
	 * (sizeof(*packet) == sizeof(struct ethhdr)), additionally the
	 * h_proto field is in the same place so we just leave it alone and
	 * overwrite the remaining fields.
	 */
	packet = (struct vl600_pkt_hdr *) skb->data;
	memset(&packet->dummy, 0, sizeof(packet->dummy));
	packet->len = cpu_to_le32(orig_len);

	frame = (struct vl600_frame_hdr *) skb_push(skb, sizeof(*frame));
	memset(frame, 0, sizeof(*frame));
	frame->len = cpu_to_le32(full_len);
	frame->serial = cpu_to_le32(serial++);
	frame->pkt_cnt = cpu_to_le32(1);

	if (skb->len < full_len) /* Pad */
		skb_put(skb, full_len - skb->len);

	/* The VL600 wants IPv6 packets to have an IPv4 ethertype
	 * Check if this is an IPv6 packet, and set the ethertype
	 * to 0x800
	 */
	if ((skb->data[sizeof(struct vl600_pkt_hdr *) + 0x22] & 0xf0) == 0x60) {
		skb->data[sizeof(struct vl600_pkt_hdr *) + 0x20] = 0x08;
		skb->data[sizeof(struct vl600_pkt_hdr *) + 0x21] = 0;
	}

	return skb;
}

static const struct driver_info	vl600_info = {
	.description	= "LG VL600 modem",
	.flags		= FLAG_ETHER | FLAG_RX_ASSEMBLE,
	.bind		= vl600_bind,
	.unbind		= vl600_unbind,
	.status		= usbnet_cdc_status,
	.rx_fixup	= vl600_rx_fixup,
	.tx_fixup	= vl600_tx_fixup,
};

static const struct usb_device_id products[] = {
	{
		USB_DEVICE_AND_INTERFACE_INFO(0x1004, 0x61aa, USB_CLASS_COMM,
				USB_CDC_SUBCLASS_ETHERNET, USB_CDC_PROTO_NONE),
		.driver_info	= (unsigned long) &vl600_info,
	},
	{},	/* End */
};
MODULE_DEVICE_TABLE(usb, products);

static struct usb_driver lg_vl600_driver = {
	.name		= "lg-vl600",
	.id_table	= products,
	.probe		= usbnet_probe,
	.disconnect	= usbnet_disconnect,
	.suspend	= usbnet_suspend,
	.resume		= usbnet_resume,
};

static int __init vl600_init(void)
{
	return usb_register(&lg_vl600_driver);
}
module_init(vl600_init);

static void __exit vl600_exit(void)
{
	usb_deregister(&lg_vl600_driver);
}
module_exit(vl600_exit);

MODULE_AUTHOR("Anrzej Zaborowski");
MODULE_DESCRIPTION("LG-VL600 modem's ethernet link");
MODULE_LICENSE("GPL");
Commit	Line	Data
7a635ea9 AZ	1	/*
	2	* Ethernet interface part of the LG VL600 LTE modem (4G dongle)
	3	*
	4	* Copyright (C) 2011 Intel Corporation
	5	* Author: Andrzej Zaborowski <balrogg@gmail.com>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*/
	21	#include <linux/etherdevice.h>
	22	#include <linux/ethtool.h>
	23	#include <linux/mii.h>
	24	#include <linux/usb.h>
	25	#include <linux/usb/cdc.h>
	26	#include <linux/usb/usbnet.h>
	27	#include <linux/if_ether.h>
	28	#include <linux/if_arp.h>
	29	#include <linux/inetdevice.h>
	30
	31	/*
	32	* The device has a CDC ACM port for modem control (it claims to be
	33	* CDC ACM anyway) and a CDC Ethernet port for actual network data.
	34	* It will however ignore data on both ports that is not encapsulated
	35	* in a specific way, any data returned is also encapsulated the same
	36	* way. The headers don't seem to follow any popular standard.
	37	*
	38	* This driver adds and strips these headers from the ethernet frames
	39	* sent/received from the CDC Ethernet port. The proprietary header
	40	* replaces the standard ethernet header in a packet so only actual
	41	* ethernet frames are allowed. The headers allow some form of
	42	* multiplexing by using non standard values of the .h_proto field.
	43	* Windows/Mac drivers do send a couple of such frames to the device
	44	* during initialisation, with protocol set to 0x0906 or 0x0b06 and (what
	45	* seems to be) a flag in the .dummy_flags. This doesn't seem necessary
	46	* for modem operation but can possibly be used for GPS or other funcitons.
	47	*/
	48
	49	struct vl600_frame_hdr {
	50	__le32 len;
	51	__le32 serial;
	52	__le32 pkt_cnt;
	53	__le32 dummy_flags;
	54	__le32 dummy;
	55	__le32 magic;
	56	} __attribute__((packed));
	57
	58	struct vl600_pkt_hdr {
	59	__le32 dummy[2];
	60	__le32 len;
	61	__be16 h_proto;
	62	} __attribute__((packed));
	63
	64	struct vl600_state {
65	struct sk_buff *current_rx_buf;
66	};
67
68	static int vl600_bind(struct usbnet dev, struct usb_interface intf)
69	{
70	int ret;
71	struct vl600_state *s = kzalloc(sizeof(struct vl600_state), GFP_KERNEL);
72
73	if (!s)
74	return -ENOMEM;
75
76	ret = usbnet_cdc_bind(dev, intf);
77	if (ret) {
78	kfree(s);
79	return ret;
80	}
81
82	dev->driver_priv = s;
83
84	/* ARP packets don't go through, but they're also of no use. The
85	* subnet has only two hosts anyway: us and the gateway / DHCP
86	* server (probably simulated by modem firmware or network operator)
87	* whose address changes everytime we connect to the intarwebz and
88	* who doesn't bother answering ARP requests either. So hardware
89	* addresses have no meaning, the destination and the source of every
90	* packet depend only on whether it is on the IN or OUT endpoint. */
91	dev->net->flags \|= IFF_NOARP;
2ae40ee9 MK	92	/* IPv6 NDP relies on multicast. Enable it by default. */
2ae40ee9 MK	93	dev->net->flags \|= IFF_MULTICAST;
7a635ea9 AZ	94
	95	return ret;
	96	}
	97
	98	static void vl600_unbind(struct usbnet dev, struct usb_interface intf)
	99	{
	100	struct vl600_state *s = dev->driver_priv;
	101
	102	if (s->current_rx_buf)
	103	dev_kfree_skb(s->current_rx_buf);
	104
	105	kfree(s);
	106
	107	return usbnet_cdc_unbind(dev, intf);
	108	}
	109
	110	static int vl600_rx_fixup(struct usbnet dev, struct sk_buff skb)
	111	{
	112	struct vl600_frame_hdr *frame;
	113	struct vl600_pkt_hdr *packet;
	114	struct ethhdr *ethhdr;
	115	int packet_len, count;
	116	struct sk_buff *buf = skb;
	117	struct sk_buff *clone;
	118	struct vl600_state *s = dev->driver_priv;
	119
	120	/* Frame lengths are generally 4B multiplies but every couple of
	121	* hours there's an odd number of bytes sized yet correct frame,
	122	* so don't require this. */
	123
	124	/* Allow a packet (or multiple packets batched together) to be
	125	* split across many frames. We don't allow a new batch to
	126	* begin in the same frame another one is ending however, and no
	127	* leading or trailing pad bytes. */
	128	if (s->current_rx_buf) {
	129	frame = (struct vl600_frame_hdr *) s->current_rx_buf->data;
	130	if (skb->len + s->current_rx_buf->len >
	131	le32_to_cpup(&frame->len)) {
	132	netif_err(dev, ifup, dev->net, "Fragment too long\n");
	133	dev->net->stats.rx_length_errors++;
	134	goto error;
	135	}
	136
	137	buf = s->current_rx_buf;
	138	memcpy(skb_put(buf, skb->len), skb->data, skb->len);
	139	} else if (skb->len < 4) {
	140	netif_err(dev, ifup, dev->net, "Frame too short\n");
	141	dev->net->stats.rx_length_errors++;
	142	goto error;
	143	}
	144
	145	frame = (struct vl600_frame_hdr *) buf->data;
	146	/* NOTE: Should check that frame->magic == 0x53544448?
	147	* Otherwise if we receive garbage at the beginning of the frame
	148	* we may end up allocating a huge buffer and saving all the
	149	* future incoming data into it. */
	150
	151	if (buf->len < sizeof(*frame) \|\|
	152	buf->len != le32_to_cpup(&frame->len)) {
	153	/* Save this fragment for later assembly */
	154	if (s->current_rx_buf)
	155	return 0;
	156
	157	s->current_rx_buf = skb_copy_expand(skb, 0,
158	le32_to_cpup(&frame->len), GFP_ATOMIC);
159	if (!s->current_rx_buf) {
160	netif_err(dev, ifup, dev->net, "Reserving %i bytes "
161	"for packet assembly failed.\n",
162	le32_to_cpup(&frame->len));
163	dev->net->stats.rx_errors++;
164	}
165
166	return 0;
167	}
168
169	count = le32_to_cpup(&frame->pkt_cnt);
170
171	skb_pull(buf, sizeof(*frame));
172
173	while (count--) {
174	if (buf->len < sizeof(*packet)) {
175	netif_err(dev, ifup, dev->net, "Packet too short\n");
176	goto error;
177	}
178
179	packet = (struct vl600_pkt_hdr *) buf->data;
180	packet_len = sizeof(*packet) + le32_to_cpup(&packet->len);
181	if (packet_len > buf->len) {
182	netif_err(dev, ifup, dev->net,
183	"Bad packet length stored in header\n");
184	goto error;
185	}
186
187	/* Packet header is same size as the ethernet header
188	* (sizeof(packet) == sizeof(ethhdr)), additionally
189	* the h_proto field is in the same place so we just leave it
190	* alone and fill in the remaining fields.
191	*/
192	ethhdr = (struct ethhdr *) skb->data;
193	if (be16_to_cpup(&ethhdr->h_proto) == ETH_P_ARP &&
194	buf->len > 0x26) {
195	/* Copy the addresses from packet contents */
196	memcpy(ethhdr->h_source,
197	&buf->data[sizeof(*ethhdr) + 0x8],
198	ETH_ALEN);
199	memcpy(ethhdr->h_dest,
200	&buf->data[sizeof(*ethhdr) + 0x12],
201	ETH_ALEN);
202	} else {
203	memset(ethhdr->h_source, 0, ETH_ALEN);
204	memcpy(ethhdr->h_dest, dev->net->dev_addr, ETH_ALEN);
2ae40ee9 MK	205
	206	/* Inbound IPv6 packets have an IPv4 ethertype (0x800)
	207	* for some reason. Peek at the L3 header to check
	208	* for IPv6 packets, and set the ethertype to IPv6
	209	* (0x86dd) so Linux can understand it.
	210	*/
	211	if ((buf->data[sizeof(*ethhdr)] & 0xf0) == 0x60)
	212	ethhdr->h_proto = __constant_htons(ETH_P_IPV6);
7a635ea9 AZ	213	}
	214
	215	if (count) {
	216	/* Not the last packet in this batch */
	217	clone = skb_clone(buf, GFP_ATOMIC);
	218	if (!clone)
	219	goto error;
	220
	221	skb_trim(clone, packet_len);
	222	usbnet_skb_return(dev, clone);
	223
	224	skb_pull(buf, (packet_len + 3) & ~3);
	225	} else {
	226	skb_trim(buf, packet_len);
	227
	228	if (s->current_rx_buf) {
	229	usbnet_skb_return(dev, buf);
	230	s->current_rx_buf = NULL;
	231	return 0;
	232	}
	233
	234	return 1;
	235	}
	236	}
	237
	238	error:
	239	if (s->current_rx_buf) {
	240	dev_kfree_skb_any(s->current_rx_buf);
	241	s->current_rx_buf = NULL;
	242	}
	243	dev->net->stats.rx_errors++;
	244	return 0;
	245	}
	246
	247	static struct sk_buff vl600_tx_fixup(struct usbnet dev,
	248	struct sk_buff *skb, gfp_t flags)
	249	{
	250	struct sk_buff *ret;
	251	struct vl600_frame_hdr *frame;
	252	struct vl600_pkt_hdr *packet;
	253	static uint32_t serial = 1;
	254	int orig_len = skb->len - sizeof(struct ethhdr);
	255	int full_len = (skb->len + sizeof(struct vl600_frame_hdr) + 3) & ~3;
	256
	257	frame = (struct vl600_frame_hdr *) skb->data;
	258	if (skb->len > sizeof(*frame) && skb->len == le32_to_cpup(&frame->len))
	259	return skb; /* Already encapsulated? */
	260
	261	if (skb->len < sizeof(struct ethhdr))
	262	/* Drop, device can only deal with ethernet packets */
	263	return NULL;
	264
	265	if (!skb_cloned(skb)) {
	266	int headroom = skb_headroom(skb);
	267	int tailroom = skb_tailroom(skb);
	268
	269	if (tailroom >= full_len - skb->len - sizeof(*frame) &&
	270	headroom >= sizeof(*frame))
	271	/* There's enough head and tail room */
	272	goto encapsulate;
	273
	274	if (headroom + tailroom + skb->len >= full_len) {
	275	/* There's enough total room, just readjust */
	276	skb->data = memmove(skb->head + sizeof(*frame),
277	skb->data, skb->len);
278	skb_set_tail_pointer(skb, skb->len);
279	goto encapsulate;
280	}
281	}
282
283	/* Alloc a new skb with the required size */
284	ret = skb_copy_expand(skb, sizeof(struct vl600_frame_hdr), full_len -
285	skb->len - sizeof(struct vl600_frame_hdr), flags);
286	dev_kfree_skb_any(skb);
287	if (!ret)
288	return ret;
289	skb = ret;
290
291	encapsulate:
292	/* Packet header is same size as ethernet packet header
293	* (sizeof(*packet) == sizeof(struct ethhdr)), additionally the
294	* h_proto field is in the same place so we just leave it alone and
295	* overwrite the remaining fields.
296	*/
297	packet = (struct vl600_pkt_hdr *) skb->data;
298	memset(&packet->dummy, 0, sizeof(packet->dummy));
299	packet->len = cpu_to_le32(orig_len);
300
301	frame = (struct vl600_frame_hdr ) skb_push(skb, sizeof(frame));
302	memset(frame, 0, sizeof(*frame));
303	frame->len = cpu_to_le32(full_len);
304	frame->serial = cpu_to_le32(serial++);
305	frame->pkt_cnt = cpu_to_le32(1);
306
307	if (skb->len < full_len) /* Pad */
308	skb_put(skb, full_len - skb->len);
309
2ae40ee9 MK	310	/* The VL600 wants IPv6 packets to have an IPv4 ethertype
	311	* Check if this is an IPv6 packet, and set the ethertype
	312	* to 0x800
	313	*/
	314	if ((skb->data[sizeof(struct vl600_pkt_hdr *) + 0x22] & 0xf0) == 0x60) {
	315	skb->data[sizeof(struct vl600_pkt_hdr *) + 0x20] = 0x08;
	316	skb->data[sizeof(struct vl600_pkt_hdr *) + 0x21] = 0;
	317	}
	318
7a635ea9 AZ	319	return skb;
	320	}
	321
	322	static const struct driver_info vl600_info = {
	323	.description = "LG VL600 modem",
	324	.flags = FLAG_ETHER \| FLAG_RX_ASSEMBLE,
	325	.bind = vl600_bind,
	326	.unbind = vl600_unbind,
	327	.status = usbnet_cdc_status,
	328	.rx_fixup = vl600_rx_fixup,
	329	.tx_fixup = vl600_tx_fixup,
	330	};
	331
	332	static const struct usb_device_id products[] = {
	333	{
	334	USB_DEVICE_AND_INTERFACE_INFO(0x1004, 0x61aa, USB_CLASS_COMM,
	335	USB_CDC_SUBCLASS_ETHERNET, USB_CDC_PROTO_NONE),
	336	.driver_info = (unsigned long) &vl600_info,
	337	},
	338	{}, /* End */
	339	};
	340	MODULE_DEVICE_TABLE(usb, products);
	341
	342	static struct usb_driver lg_vl600_driver = {
	343	.name = "lg-vl600",
	344	.id_table = products,
	345	.probe = usbnet_probe,
	346	.disconnect = usbnet_disconnect,
	347	.suspend = usbnet_suspend,
	348	.resume = usbnet_resume,
	349	};
	350
	351	static int __init vl600_init(void)
	352	{
	353	return usb_register(&lg_vl600_driver);
	354	}
	355	module_init(vl600_init);
	356
	357	static void __exit vl600_exit(void)
	358	{
	359	usb_deregister(&lg_vl600_driver);
	360	}
	361	module_exit(vl600_exit);
	362
	363	MODULE_AUTHOR("Anrzej Zaborowski");
	364	MODULE_DESCRIPTION("LG-VL600 modem's ethernet link");
	365	MODULE_LICENSE("GPL");