From 7a635ea989991d7f12d57a12f2ba7cb6d211e083 Mon Sep 17 00:00:00 2001 From: Andrzej Zaborowski Date: Mon, 28 Mar 2011 12:56:33 +0000 Subject: [PATCH] net/usb: Ethernet quirks for the LG-VL600 4G modem This adds a driver for the CDC Ethernet part of this modem. The device's ID is blacklisted in cdc_ether.c and is white-listed in this new driver because of the quirks needed to make it useful. The modem's firmware exposes a CDC ACM port for modem control and a CDC Ethernet port for network data. The descriptors look fine but both ports actually are some sort of multiplexers requiring non- standard headers added/removed from every packet or they get ignored. All information is based on a usb traffic log from a Windows machine. On the Verizon 4G network I've seen speeds up to 1.1MB/s so far with this driver, a speed-o-meter site reports 16.2Mbps/10.5Mbps. Userspace scripts are required to talk to the CDC ACM port. Signed-off-by: Andrzej Zaborowski Signed-off-by: David S. Miller --- drivers/net/usb/Kconfig | 15 ++ drivers/net/usb/Makefile | 1 + drivers/net/usb/cdc_ether.c | 21 ++- drivers/net/usb/lg-vl600.c | 346 ++++++++++++++++++++++++++++++++++++ drivers/net/usb/usbnet.c | 10 +- include/linux/usb/usbnet.h | 3 + 6 files changed, 387 insertions(+), 9 deletions(-) create mode 100644 drivers/net/usb/lg-vl600.c diff --git a/drivers/net/usb/Kconfig b/drivers/net/usb/Kconfig index 6f600cced6e1..3ec22c307797 100644 --- a/drivers/net/usb/Kconfig +++ b/drivers/net/usb/Kconfig @@ -433,4 +433,19 @@ config USB_SIERRA_NET To compile this driver as a module, choose M here: the module will be called sierra_net. +config USB_VL600 + tristate "LG VL600 modem dongle" + depends on USB_NET_CDCETHER + select USB_ACM + help + Select this if you want to use an LG Electronics 4G/LTE usb modem + called VL600. This driver only handles the ethernet + interface exposed by the modem firmware. To establish a connection + you will first need a userspace program that sends the right + command to the modem through its CDC ACM port, and most + likely also a DHCP client. See this thread about using the + 4G modem from Verizon: + + http://ubuntuforums.org/showpost.php?p=10589647&postcount=17 + endmenu diff --git a/drivers/net/usb/Makefile b/drivers/net/usb/Makefile index cac170301187..c7ec8a5f0a90 100644 --- a/drivers/net/usb/Makefile +++ b/drivers/net/usb/Makefile @@ -27,4 +27,5 @@ obj-$(CONFIG_USB_IPHETH) += ipheth.o obj-$(CONFIG_USB_SIERRA_NET) += sierra_net.o obj-$(CONFIG_USB_NET_CX82310_ETH) += cx82310_eth.o obj-$(CONFIG_USB_NET_CDC_NCM) += cdc_ncm.o +obj-$(CONFIG_USB_VL600) += lg-vl600.o diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c index 9a60e415d76b..51c259b69278 100644 --- a/drivers/net/usb/cdc_ether.c +++ b/drivers/net/usb/cdc_ether.c @@ -378,7 +378,7 @@ static void dumpspeed(struct usbnet *dev, __le32 *speeds) __le32_to_cpu(speeds[1]) / 1000); } -static void cdc_status(struct usbnet *dev, struct urb *urb) +void usbnet_cdc_status(struct usbnet *dev, struct urb *urb) { struct usb_cdc_notification *event; @@ -418,8 +418,9 @@ static void cdc_status(struct usbnet *dev, struct urb *urb) break; } } +EXPORT_SYMBOL_GPL(usbnet_cdc_status); -static int cdc_bind(struct usbnet *dev, struct usb_interface *intf) +int usbnet_cdc_bind(struct usbnet *dev, struct usb_interface *intf) { int status; struct cdc_state *info = (void *) &dev->data; @@ -441,6 +442,7 @@ static int cdc_bind(struct usbnet *dev, struct usb_interface *intf) */ return 0; } +EXPORT_SYMBOL_GPL(usbnet_cdc_bind); static int cdc_manage_power(struct usbnet *dev, int on) { @@ -452,18 +454,18 @@ static const struct driver_info cdc_info = { .description = "CDC Ethernet Device", .flags = FLAG_ETHER, // .check_connect = cdc_check_connect, - .bind = cdc_bind, + .bind = usbnet_cdc_bind, .unbind = usbnet_cdc_unbind, - .status = cdc_status, + .status = usbnet_cdc_status, .manage_power = cdc_manage_power, }; static const struct driver_info mbm_info = { .description = "Mobile Broadband Network Device", .flags = FLAG_WWAN, - .bind = cdc_bind, + .bind = usbnet_cdc_bind, .unbind = usbnet_cdc_unbind, - .status = cdc_status, + .status = usbnet_cdc_status, .manage_power = cdc_manage_power, }; @@ -560,6 +562,13 @@ static const struct usb_device_id products [] = { .driver_info = 0, }, +/* LG Electronics VL600 wants additional headers on every frame */ +{ + USB_DEVICE_AND_INTERFACE_INFO(0x1004, 0x61aa, USB_CLASS_COMM, + USB_CDC_SUBCLASS_ETHERNET, USB_CDC_PROTO_NONE), + .driver_info = 0, +}, + /* * WHITELIST!!! * diff --git a/drivers/net/usb/lg-vl600.c b/drivers/net/usb/lg-vl600.c new file mode 100644 index 000000000000..1d83ccfd7277 --- /dev/null +++ b/drivers/net/usb/lg-vl600.c @@ -0,0 +1,346 @@ +/* + * Ethernet interface part of the LG VL600 LTE modem (4G dongle) + * + * Copyright (C) 2011 Intel Corporation + * Author: Andrzej Zaborowski + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * 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; + + 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(ðhdr->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); + } + + 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); + + 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"); diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index 95c41d56631c..cf58b7682565 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -387,8 +387,12 @@ static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags) static inline void rx_process (struct usbnet *dev, struct sk_buff *skb) { if (dev->driver_info->rx_fixup && - !dev->driver_info->rx_fixup (dev, skb)) - goto error; + !dev->driver_info->rx_fixup (dev, skb)) { + /* With RX_ASSEMBLE, rx_fixup() must update counters */ + if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE)) + dev->net->stats.rx_errors++; + goto done; + } // else network stack removes extra byte if we forced a short packet if (skb->len) { @@ -401,8 +405,8 @@ static inline void rx_process (struct usbnet *dev, struct sk_buff *skb) } netif_dbg(dev, rx_err, dev->net, "drop\n"); -error: dev->net->stats.rx_errors++; +done: skb_queue_tail(&dev->done, skb); } diff --git a/include/linux/usb/usbnet.h b/include/linux/usb/usbnet.h index 44842c8d38c0..201f2228f731 100644 --- a/include/linux/usb/usbnet.h +++ b/include/linux/usb/usbnet.h @@ -102,6 +102,7 @@ struct driver_info { * Affects statistic (counters) and short packet handling. */ #define FLAG_MULTI_PACKET 0x1000 +#define FLAG_RX_ASSEMBLE 0x2000 /* rx packets may span >1 frames */ /* init device ... can sleep, or cause probe() failure */ int (*bind)(struct usbnet *, struct usb_interface *); @@ -172,7 +173,9 @@ struct cdc_state { }; extern int usbnet_generic_cdc_bind(struct usbnet *, struct usb_interface *); +extern int usbnet_cdc_bind(struct usbnet *, struct usb_interface *); extern void usbnet_cdc_unbind(struct usbnet *, struct usb_interface *); +extern void usbnet_cdc_status(struct usbnet *, struct urb *); /* CDC and RNDIS support the same host-chosen packet filters for IN transfers */ #define DEFAULT_FILTER (USB_CDC_PACKET_TYPE_BROADCAST \ -- 2.20.1