linux/drivers/net/usb/cdc_mbim.c

626 lines
17 KiB
C

/*
* Copyright (c) 2012 Smith Micro Software, Inc.
* Copyright (c) 2012 Bjørn Mork <bjorn@mork.no>
*
* This driver is based on and reuse most of cdc_ncm, which is
* Copyright (C) ST-Ericsson 2010-2012
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/ethtool.h>
#include <linux/if_vlan.h>
#include <linux/ip.h>
#include <linux/mii.h>
#include <linux/usb.h>
#include <linux/usb/cdc.h>
#include <linux/usb/usbnet.h>
#include <linux/usb/cdc-wdm.h>
#include <linux/usb/cdc_ncm.h>
#include <net/ipv6.h>
#include <net/addrconf.h>
/* alternative VLAN for IP session 0 if not untagged */
#define MBIM_IPS0_VID 4094
/* driver specific data - must match cdc_ncm usage */
struct cdc_mbim_state {
struct cdc_ncm_ctx *ctx;
atomic_t pmcount;
struct usb_driver *subdriver;
unsigned long _unused;
unsigned long flags;
};
/* flags for the cdc_mbim_state.flags field */
enum cdc_mbim_flags {
FLAG_IPS0_VLAN = 1 << 0, /* IP session 0 is tagged */
};
/* using a counter to merge subdriver requests with our own into a combined state */
static int cdc_mbim_manage_power(struct usbnet *dev, int on)
{
struct cdc_mbim_state *info = (void *)&dev->data;
int rv = 0;
dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(&info->pmcount), on);
if ((on && atomic_add_return(1, &info->pmcount) == 1) || (!on && atomic_dec_and_test(&info->pmcount))) {
/* need autopm_get/put here to ensure the usbcore sees the new value */
rv = usb_autopm_get_interface(dev->intf);
dev->intf->needs_remote_wakeup = on;
if (!rv)
usb_autopm_put_interface(dev->intf);
}
return 0;
}
static int cdc_mbim_wdm_manage_power(struct usb_interface *intf, int status)
{
struct usbnet *dev = usb_get_intfdata(intf);
/* can be called while disconnecting */
if (!dev)
return 0;
return cdc_mbim_manage_power(dev, status);
}
static int cdc_mbim_rx_add_vid(struct net_device *netdev, __be16 proto, u16 vid)
{
struct usbnet *dev = netdev_priv(netdev);
struct cdc_mbim_state *info = (void *)&dev->data;
/* creation of this VLAN is a request to tag IP session 0 */
if (vid == MBIM_IPS0_VID)
info->flags |= FLAG_IPS0_VLAN;
else
if (vid >= 512) /* we don't map these to MBIM session */
return -EINVAL;
return 0;
}
static int cdc_mbim_rx_kill_vid(struct net_device *netdev, __be16 proto, u16 vid)
{
struct usbnet *dev = netdev_priv(netdev);
struct cdc_mbim_state *info = (void *)&dev->data;
/* this is a request for an untagged IP session 0 */
if (vid == MBIM_IPS0_VID)
info->flags &= ~FLAG_IPS0_VLAN;
return 0;
}
static const struct net_device_ops cdc_mbim_netdev_ops = {
.ndo_open = usbnet_open,
.ndo_stop = usbnet_stop,
.ndo_start_xmit = usbnet_start_xmit,
.ndo_tx_timeout = usbnet_tx_timeout,
.ndo_change_mtu = usbnet_change_mtu,
.ndo_set_mac_address = eth_mac_addr,
.ndo_validate_addr = eth_validate_addr,
.ndo_vlan_rx_add_vid = cdc_mbim_rx_add_vid,
.ndo_vlan_rx_kill_vid = cdc_mbim_rx_kill_vid,
};
/* Change the control interface altsetting and update the .driver_info
* pointer if the matching entry after changing class codes points to
* a different struct
*/
static int cdc_mbim_set_ctrlalt(struct usbnet *dev, struct usb_interface *intf, u8 alt)
{
struct usb_driver *driver = to_usb_driver(intf->dev.driver);
const struct usb_device_id *id;
struct driver_info *info;
int ret;
ret = usb_set_interface(dev->udev,
intf->cur_altsetting->desc.bInterfaceNumber,
alt);
if (ret)
return ret;
id = usb_match_id(intf, driver->id_table);
if (!id)
return -ENODEV;
info = (struct driver_info *)id->driver_info;
if (info != dev->driver_info) {
dev_dbg(&intf->dev, "driver_info updated to '%s'\n",
info->description);
dev->driver_info = info;
}
return 0;
}
static int cdc_mbim_bind(struct usbnet *dev, struct usb_interface *intf)
{
struct cdc_ncm_ctx *ctx;
struct usb_driver *subdriver = ERR_PTR(-ENODEV);
int ret = -ENODEV;
u8 data_altsetting = 1;
struct cdc_mbim_state *info = (void *)&dev->data;
/* should we change control altsetting on a NCM/MBIM function? */
if (cdc_ncm_select_altsetting(intf) == CDC_NCM_COMM_ALTSETTING_MBIM) {
data_altsetting = CDC_NCM_DATA_ALTSETTING_MBIM;
ret = cdc_mbim_set_ctrlalt(dev, intf, CDC_NCM_COMM_ALTSETTING_MBIM);
if (ret)
goto err;
ret = -ENODEV;
}
/* we will hit this for NCM/MBIM functions if prefer_mbim is false */
if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
goto err;
ret = cdc_ncm_bind_common(dev, intf, data_altsetting, 0);
if (ret)
goto err;
ctx = info->ctx;
/* The MBIM descriptor and the status endpoint are required */
if (ctx->mbim_desc && dev->status)
subdriver = usb_cdc_wdm_register(ctx->control,
&dev->status->desc,
le16_to_cpu(ctx->mbim_desc->wMaxControlMessage),
cdc_mbim_wdm_manage_power);
if (IS_ERR(subdriver)) {
ret = PTR_ERR(subdriver);
cdc_ncm_unbind(dev, intf);
goto err;
}
/* can't let usbnet use the interrupt endpoint */
dev->status = NULL;
info->subdriver = subdriver;
/* MBIM cannot do ARP */
dev->net->flags |= IFF_NOARP;
/* no need to put the VLAN tci in the packet headers */
dev->net->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_FILTER;
/* monitor VLAN additions and removals */
dev->net->netdev_ops = &cdc_mbim_netdev_ops;
err:
return ret;
}
static void cdc_mbim_unbind(struct usbnet *dev, struct usb_interface *intf)
{
struct cdc_mbim_state *info = (void *)&dev->data;
struct cdc_ncm_ctx *ctx = info->ctx;
/* disconnect subdriver from control interface */
if (info->subdriver && info->subdriver->disconnect)
info->subdriver->disconnect(ctx->control);
info->subdriver = NULL;
/* let NCM unbind clean up both control and data interface */
cdc_ncm_unbind(dev, intf);
}
/* verify that the ethernet protocol is IPv4 or IPv6 */
static bool is_ip_proto(__be16 proto)
{
switch (proto) {
case htons(ETH_P_IP):
case htons(ETH_P_IPV6):
return true;
}
return false;
}
static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
{
struct sk_buff *skb_out;
struct cdc_mbim_state *info = (void *)&dev->data;
struct cdc_ncm_ctx *ctx = info->ctx;
__le32 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN);
u16 tci = 0;
bool is_ip;
u8 *c;
if (!ctx)
goto error;
if (skb) {
if (skb->len <= ETH_HLEN)
goto error;
/* Some applications using e.g. packet sockets will
* bypass the VLAN acceleration and create tagged
* ethernet frames directly. We primarily look for
* the accelerated out-of-band tag, but fall back if
* required
*/
skb_reset_mac_header(skb);
if (vlan_get_tag(skb, &tci) < 0 && skb->len > VLAN_ETH_HLEN &&
__vlan_get_tag(skb, &tci) == 0) {
is_ip = is_ip_proto(vlan_eth_hdr(skb)->h_vlan_encapsulated_proto);
skb_pull(skb, VLAN_ETH_HLEN);
} else {
is_ip = is_ip_proto(eth_hdr(skb)->h_proto);
skb_pull(skb, ETH_HLEN);
}
/* Is IP session <0> tagged too? */
if (info->flags & FLAG_IPS0_VLAN) {
/* drop all untagged packets */
if (!tci)
goto error;
/* map MBIM_IPS0_VID to IPS<0> */
if (tci == MBIM_IPS0_VID)
tci = 0;
}
/* mapping VLANs to MBIM sessions:
* no tag => IPS session <0> if !FLAG_IPS0_VLAN
* 1 - 255 => IPS session <vlanid>
* 256 - 511 => DSS session <vlanid - 256>
* 512 - 4093 => unsupported, drop
* 4094 => IPS session <0> if FLAG_IPS0_VLAN
*/
switch (tci & 0x0f00) {
case 0x0000: /* VLAN ID 0 - 255 */
if (!is_ip)
goto error;
c = (u8 *)&sign;
c[3] = tci;
break;
case 0x0100: /* VLAN ID 256 - 511 */
if (is_ip)
goto error;
sign = cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN);
c = (u8 *)&sign;
c[3] = tci;
break;
default:
netif_err(dev, tx_err, dev->net,
"unsupported tci=0x%04x\n", tci);
goto error;
}
}
spin_lock_bh(&ctx->mtx);
skb_out = cdc_ncm_fill_tx_frame(dev, skb, sign);
spin_unlock_bh(&ctx->mtx);
return skb_out;
error:
if (skb)
dev_kfree_skb_any(skb);
return NULL;
}
/* Some devices are known to send Neigbor Solicitation messages and
* require Neigbor Advertisement replies. The IPv6 core will not
* respond since IFF_NOARP is set, so we must handle them ourselves.
*/
static void do_neigh_solicit(struct usbnet *dev, u8 *buf, u16 tci)
{
struct ipv6hdr *iph = (void *)buf;
struct nd_msg *msg = (void *)(iph + 1);
struct net_device *netdev;
struct inet6_dev *in6_dev;
bool is_router;
/* we'll only respond to requests from unicast addresses to
* our solicited node addresses.
*/
if (!ipv6_addr_is_solict_mult(&iph->daddr) ||
!(ipv6_addr_type(&iph->saddr) & IPV6_ADDR_UNICAST))
return;
/* need to send the NA on the VLAN dev, if any */
rcu_read_lock();
if (tci) {
netdev = __vlan_find_dev_deep_rcu(dev->net, htons(ETH_P_8021Q),
tci);
if (!netdev) {
rcu_read_unlock();
return;
}
} else {
netdev = dev->net;
}
dev_hold(netdev);
rcu_read_unlock();
in6_dev = in6_dev_get(netdev);
if (!in6_dev)
goto out;
is_router = !!in6_dev->cnf.forwarding;
in6_dev_put(in6_dev);
/* ipv6_stub != NULL if in6_dev_get returned an inet6_dev */
ipv6_stub->ndisc_send_na(netdev, &iph->saddr, &msg->target,
is_router /* router */,
true /* solicited */,
false /* override */,
true /* inc_opt */);
out:
dev_put(netdev);
}
static bool is_neigh_solicit(u8 *buf, size_t len)
{
struct ipv6hdr *iph = (void *)buf;
struct nd_msg *msg = (void *)(iph + 1);
return (len >= sizeof(struct ipv6hdr) + sizeof(struct nd_msg) &&
iph->nexthdr == IPPROTO_ICMPV6 &&
msg->icmph.icmp6_code == 0 &&
msg->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION);
}
static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_t len, u16 tci)
{
__be16 proto = htons(ETH_P_802_3);
struct sk_buff *skb = NULL;
if (tci < 256 || tci == MBIM_IPS0_VID) { /* IPS session? */
if (len < sizeof(struct iphdr))
goto err;
switch (*buf & 0xf0) {
case 0x40:
proto = htons(ETH_P_IP);
break;
case 0x60:
if (is_neigh_solicit(buf, len))
do_neigh_solicit(dev, buf, tci);
proto = htons(ETH_P_IPV6);
break;
default:
goto err;
}
}
skb = netdev_alloc_skb_ip_align(dev->net, len + ETH_HLEN);
if (!skb)
goto err;
/* add an ethernet header */
skb_put(skb, ETH_HLEN);
skb_reset_mac_header(skb);
eth_hdr(skb)->h_proto = proto;
eth_zero_addr(eth_hdr(skb)->h_source);
memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
/* add datagram */
memcpy(skb_put(skb, len), buf, len);
/* map MBIM session to VLAN */
if (tci)
__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), tci);
err:
return skb;
}
static int cdc_mbim_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
{
struct sk_buff *skb;
struct cdc_mbim_state *info = (void *)&dev->data;
struct cdc_ncm_ctx *ctx = info->ctx;
int len;
int nframes;
int x;
int offset;
struct usb_cdc_ncm_ndp16 *ndp16;
struct usb_cdc_ncm_dpe16 *dpe16;
int ndpoffset;
int loopcount = 50; /* arbitrary max preventing infinite loop */
u32 payload = 0;
u8 *c;
u16 tci;
ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
if (ndpoffset < 0)
goto error;
next_ndp:
nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
if (nframes < 0)
goto error;
ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
switch (ndp16->dwSignature & cpu_to_le32(0x00ffffff)) {
case cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN):
c = (u8 *)&ndp16->dwSignature;
tci = c[3];
/* tag IPS<0> packets too if MBIM_IPS0_VID exists */
if (!tci && info->flags & FLAG_IPS0_VLAN)
tci = MBIM_IPS0_VID;
break;
case cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN):
c = (u8 *)&ndp16->dwSignature;
tci = c[3] + 256;
break;
default:
netif_dbg(dev, rx_err, dev->net,
"unsupported NDP signature <0x%08x>\n",
le32_to_cpu(ndp16->dwSignature));
goto err_ndp;
}
dpe16 = ndp16->dpe16;
for (x = 0; x < nframes; x++, dpe16++) {
offset = le16_to_cpu(dpe16->wDatagramIndex);
len = le16_to_cpu(dpe16->wDatagramLength);
/*
* CDC NCM ch. 3.7
* All entries after first NULL entry are to be ignored
*/
if ((offset == 0) || (len == 0)) {
if (!x)
goto err_ndp; /* empty NTB */
break;
}
/* sanity checking */
if (((offset + len) > skb_in->len) || (len > ctx->rx_max)) {
netif_dbg(dev, rx_err, dev->net,
"invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
x, offset, len, skb_in);
if (!x)
goto err_ndp;
break;
} else {
skb = cdc_mbim_process_dgram(dev, skb_in->data + offset, len, tci);
if (!skb)
goto error;
usbnet_skb_return(dev, skb);
payload += len; /* count payload bytes in this NTB */
}
}
err_ndp:
/* are there more NDPs to process? */
ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
if (ndpoffset && loopcount--)
goto next_ndp;
/* update stats */
ctx->rx_overhead += skb_in->len - payload;
ctx->rx_ntbs++;
return 1;
error:
return 0;
}
static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message)
{
int ret = -ENODEV;
struct usbnet *dev = usb_get_intfdata(intf);
struct cdc_mbim_state *info = (void *)&dev->data;
struct cdc_ncm_ctx *ctx = info->ctx;
if (!ctx)
goto error;
/*
* Both usbnet_suspend() and subdriver->suspend() MUST return 0
* in system sleep context, otherwise, the resume callback has
* to recover device from previous suspend failure.
*/
ret = usbnet_suspend(intf, message);
if (ret < 0)
goto error;
if (intf == ctx->control && info->subdriver && info->subdriver->suspend)
ret = info->subdriver->suspend(intf, message);
if (ret < 0)
usbnet_resume(intf);
error:
return ret;
}
static int cdc_mbim_resume(struct usb_interface *intf)
{
int ret = 0;
struct usbnet *dev = usb_get_intfdata(intf);
struct cdc_mbim_state *info = (void *)&dev->data;
struct cdc_ncm_ctx *ctx = info->ctx;
bool callsub = (intf == ctx->control && info->subdriver && info->subdriver->resume);
if (callsub)
ret = info->subdriver->resume(intf);
if (ret < 0)
goto err;
ret = usbnet_resume(intf);
if (ret < 0 && callsub)
info->subdriver->suspend(intf, PMSG_SUSPEND);
err:
return ret;
}
static const struct driver_info cdc_mbim_info = {
.description = "CDC MBIM",
.flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
.bind = cdc_mbim_bind,
.unbind = cdc_mbim_unbind,
.manage_power = cdc_mbim_manage_power,
.rx_fixup = cdc_mbim_rx_fixup,
.tx_fixup = cdc_mbim_tx_fixup,
};
/* MBIM and NCM devices should not need a ZLP after NTBs with
* dwNtbOutMaxSize length. Nevertheless, a number of devices from
* different vendor IDs will fail unless we send ZLPs, forcing us
* to make this the default.
*
* This default may cause a performance penalty for spec conforming
* devices wanting to take advantage of optimizations possible without
* ZLPs. A whitelist is added in an attempt to avoid this for devices
* known to conform to the MBIM specification.
*
* All known devices supporting NCM compatibility mode are also
* conforming to the NCM and MBIM specifications. For this reason, the
* NCM subclass entry is also in the ZLP whitelist.
*/
static const struct driver_info cdc_mbim_info_zlp = {
.description = "CDC MBIM",
.flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
.bind = cdc_mbim_bind,
.unbind = cdc_mbim_unbind,
.manage_power = cdc_mbim_manage_power,
.rx_fixup = cdc_mbim_rx_fixup,
.tx_fixup = cdc_mbim_tx_fixup,
};
static const struct usb_device_id mbim_devs[] = {
/* This duplicate NCM entry is intentional. MBIM devices can
* be disguised as NCM by default, and this is necessary to
* allow us to bind the correct driver_info to such devices.
*
* bind() will sort out this for us, selecting the correct
* entry and reject the other
*/
{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
.driver_info = (unsigned long)&cdc_mbim_info,
},
/* ZLP conformance whitelist: All Ericsson MBIM devices */
{ USB_VENDOR_AND_INTERFACE_INFO(0x0bdb, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
.driver_info = (unsigned long)&cdc_mbim_info,
},
/* default entry */
{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
.driver_info = (unsigned long)&cdc_mbim_info_zlp,
},
{
},
};
MODULE_DEVICE_TABLE(usb, mbim_devs);
static struct usb_driver cdc_mbim_driver = {
.name = "cdc_mbim",
.id_table = mbim_devs,
.probe = usbnet_probe,
.disconnect = usbnet_disconnect,
.suspend = cdc_mbim_suspend,
.resume = cdc_mbim_resume,
.reset_resume = cdc_mbim_resume,
.supports_autosuspend = 1,
.disable_hub_initiated_lpm = 1,
};
module_usb_driver(cdc_mbim_driver);
MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>");
MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
MODULE_DESCRIPTION("USB CDC MBIM host driver");
MODULE_LICENSE("GPL");