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linux-next/drivers/net/usb/cdc_ncm.c
Bjørn Mork 67a366064a net: cdc_ncm: demote "unexpected notification" to debug level
Receiving unhandled notifications is most certainly not an error
and should not be logged as one.  Knowing that the device sends
notifications we don't handle is useful for developers, but there
is very little a user can do about this.  The message is therefore
just annoying noise to most users with devices sending unhandled
notifications like e.g. USB_CDC_NOTIFY_RESPONSE_AVAILABLE

Cc: Alexey Orishko <alexey.orishko@stericsson.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-08 16:55:28 -04:00

1285 lines
36 KiB
C

/*
* cdc_ncm.c
*
* Copyright (C) ST-Ericsson 2010-2012
* Contact: Alexey Orishko <alexey.orishko@stericsson.com>
* Original author: Hans Petter Selasky <hans.petter.selasky@stericsson.com>
*
* USB Host Driver for Network Control Model (NCM)
* http://www.usb.org/developers/devclass_docs/NCM10.zip
*
* The NCM encoding, decoding and initialization logic
* derives from FreeBSD 8.x. if_cdce.c and if_cdcereg.h
*
* This software is available to you under a choice of one of two
* licenses. You may choose this file to be licensed under the terms
* of the GNU General Public License (GPL) Version 2 or the 2-clause
* BSD license listed below:
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/ctype.h>
#include <linux/ethtool.h>
#include <linux/workqueue.h>
#include <linux/mii.h>
#include <linux/crc32.h>
#include <linux/usb.h>
#include <linux/hrtimer.h>
#include <linux/atomic.h>
#include <linux/usb/usbnet.h>
#include <linux/usb/cdc.h>
#include <linux/usb/cdc_ncm.h>
#define DRIVER_VERSION "14-Mar-2012"
#if IS_ENABLED(CONFIG_USB_NET_CDC_MBIM)
static bool prefer_mbim = true;
#else
static bool prefer_mbim;
#endif
module_param(prefer_mbim, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(prefer_mbim, "Prefer MBIM setting on dual NCM/MBIM functions");
static void cdc_ncm_txpath_bh(unsigned long param);
static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
static struct usb_driver cdc_ncm_driver;
static void
cdc_ncm_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *info)
{
struct usbnet *dev = netdev_priv(net);
strlcpy(info->driver, dev->driver_name, sizeof(info->driver));
strlcpy(info->version, DRIVER_VERSION, sizeof(info->version));
strlcpy(info->fw_version, dev->driver_info->description,
sizeof(info->fw_version));
usb_make_path(dev->udev, info->bus_info, sizeof(info->bus_info));
}
static u8 cdc_ncm_setup(struct cdc_ncm_ctx *ctx)
{
u32 val;
u8 flags;
u8 iface_no;
int err;
int eth_hlen;
u16 ntb_fmt_supported;
u32 min_dgram_size;
u32 min_hdr_size;
struct usbnet *dev = netdev_priv(ctx->netdev);
iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
err = usbnet_read_cmd(dev, USB_CDC_GET_NTB_PARAMETERS,
USB_TYPE_CLASS | USB_DIR_IN
|USB_RECIP_INTERFACE,
0, iface_no, &ctx->ncm_parm,
sizeof(ctx->ncm_parm));
if (err < 0) {
pr_debug("failed GET_NTB_PARAMETERS\n");
return 1;
}
/* read correct set of parameters according to device mode */
ctx->rx_max = le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize);
ctx->tx_max = le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize);
ctx->tx_remainder = le16_to_cpu(ctx->ncm_parm.wNdpOutPayloadRemainder);
ctx->tx_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutDivisor);
ctx->tx_ndp_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutAlignment);
/* devices prior to NCM Errata shall set this field to zero */
ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
ntb_fmt_supported = le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported);
eth_hlen = ETH_HLEN;
min_dgram_size = CDC_NCM_MIN_DATAGRAM_SIZE;
min_hdr_size = CDC_NCM_MIN_HDR_SIZE;
if (ctx->mbim_desc != NULL) {
flags = ctx->mbim_desc->bmNetworkCapabilities;
eth_hlen = 0;
min_dgram_size = CDC_MBIM_MIN_DATAGRAM_SIZE;
min_hdr_size = 0;
} else if (ctx->func_desc != NULL) {
flags = ctx->func_desc->bmNetworkCapabilities;
} else {
flags = 0;
}
pr_debug("dwNtbInMaxSize=%u dwNtbOutMaxSize=%u "
"wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u "
"wNdpOutAlignment=%u wNtbOutMaxDatagrams=%u flags=0x%x\n",
ctx->rx_max, ctx->tx_max, ctx->tx_remainder, ctx->tx_modulus,
ctx->tx_ndp_modulus, ctx->tx_max_datagrams, flags);
/* max count of tx datagrams */
if ((ctx->tx_max_datagrams == 0) ||
(ctx->tx_max_datagrams > CDC_NCM_DPT_DATAGRAMS_MAX))
ctx->tx_max_datagrams = CDC_NCM_DPT_DATAGRAMS_MAX;
/* verify maximum size of received NTB in bytes */
if (ctx->rx_max < USB_CDC_NCM_NTB_MIN_IN_SIZE) {
pr_debug("Using min receive length=%d\n",
USB_CDC_NCM_NTB_MIN_IN_SIZE);
ctx->rx_max = USB_CDC_NCM_NTB_MIN_IN_SIZE;
}
if (ctx->rx_max > CDC_NCM_NTB_MAX_SIZE_RX) {
pr_debug("Using default maximum receive length=%d\n",
CDC_NCM_NTB_MAX_SIZE_RX);
ctx->rx_max = CDC_NCM_NTB_MAX_SIZE_RX;
}
/* inform device about NTB input size changes */
if (ctx->rx_max != le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize)) {
__le32 dwNtbInMaxSize = cpu_to_le32(ctx->rx_max);
err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_INPUT_SIZE,
USB_TYPE_CLASS | USB_DIR_OUT
| USB_RECIP_INTERFACE,
0, iface_no, &dwNtbInMaxSize, 4);
if (err < 0)
pr_debug("Setting NTB Input Size failed\n");
}
/* verify maximum size of transmitted NTB in bytes */
if ((ctx->tx_max <
(min_hdr_size + min_dgram_size)) ||
(ctx->tx_max > CDC_NCM_NTB_MAX_SIZE_TX)) {
pr_debug("Using default maximum transmit length=%d\n",
CDC_NCM_NTB_MAX_SIZE_TX);
ctx->tx_max = CDC_NCM_NTB_MAX_SIZE_TX;
}
/*
* verify that the structure alignment is:
* - power of two
* - not greater than the maximum transmit length
* - not less than four bytes
*/
val = ctx->tx_ndp_modulus;
if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
(val != ((-val) & val)) || (val >= ctx->tx_max)) {
pr_debug("Using default alignment: 4 bytes\n");
ctx->tx_ndp_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
}
/*
* verify that the payload alignment is:
* - power of two
* - not greater than the maximum transmit length
* - not less than four bytes
*/
val = ctx->tx_modulus;
if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
(val != ((-val) & val)) || (val >= ctx->tx_max)) {
pr_debug("Using default transmit modulus: 4 bytes\n");
ctx->tx_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
}
/* verify the payload remainder */
if (ctx->tx_remainder >= ctx->tx_modulus) {
pr_debug("Using default transmit remainder: 0 bytes\n");
ctx->tx_remainder = 0;
}
/* adjust TX-remainder according to NCM specification. */
ctx->tx_remainder = ((ctx->tx_remainder - eth_hlen) &
(ctx->tx_modulus - 1));
/* additional configuration */
/* set CRC Mode */
if (flags & USB_CDC_NCM_NCAP_CRC_MODE) {
err = usbnet_write_cmd(dev, USB_CDC_SET_CRC_MODE,
USB_TYPE_CLASS | USB_DIR_OUT
| USB_RECIP_INTERFACE,
USB_CDC_NCM_CRC_NOT_APPENDED,
iface_no, NULL, 0);
if (err < 0)
pr_debug("Setting CRC mode off failed\n");
}
/* set NTB format, if both formats are supported */
if (ntb_fmt_supported & USB_CDC_NCM_NTH32_SIGN) {
err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
USB_TYPE_CLASS | USB_DIR_OUT
| USB_RECIP_INTERFACE,
USB_CDC_NCM_NTB16_FORMAT,
iface_no, NULL, 0);
if (err < 0)
pr_debug("Setting NTB format to 16-bit failed\n");
}
ctx->max_datagram_size = min_dgram_size;
/* set Max Datagram Size (MTU) */
if (flags & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE) {
__le16 max_datagram_size;
u16 eth_max_sz;
if (ctx->ether_desc != NULL)
eth_max_sz = le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
else if (ctx->mbim_desc != NULL)
eth_max_sz = le16_to_cpu(ctx->mbim_desc->wMaxSegmentSize);
else
goto max_dgram_err;
err = usbnet_read_cmd(dev, USB_CDC_GET_MAX_DATAGRAM_SIZE,
USB_TYPE_CLASS | USB_DIR_IN
| USB_RECIP_INTERFACE,
0, iface_no, &max_datagram_size, 2);
if (err < 0) {
pr_debug("GET_MAX_DATAGRAM_SIZE failed, use size=%u\n",
min_dgram_size);
} else {
ctx->max_datagram_size =
le16_to_cpu(max_datagram_size);
/* Check Eth descriptor value */
if (ctx->max_datagram_size > eth_max_sz)
ctx->max_datagram_size = eth_max_sz;
if (ctx->max_datagram_size > CDC_NCM_MAX_DATAGRAM_SIZE)
ctx->max_datagram_size = CDC_NCM_MAX_DATAGRAM_SIZE;
if (ctx->max_datagram_size < min_dgram_size)
ctx->max_datagram_size = min_dgram_size;
/* if value changed, update device */
if (ctx->max_datagram_size !=
le16_to_cpu(max_datagram_size)) {
err = usbnet_write_cmd(dev,
USB_CDC_SET_MAX_DATAGRAM_SIZE,
USB_TYPE_CLASS | USB_DIR_OUT
| USB_RECIP_INTERFACE,
0,
iface_no, &max_datagram_size,
2);
if (err < 0)
pr_debug("SET_MAX_DGRAM_SIZE failed\n");
}
}
}
max_dgram_err:
if (ctx->netdev->mtu != (ctx->max_datagram_size - eth_hlen))
ctx->netdev->mtu = ctx->max_datagram_size - eth_hlen;
return 0;
}
static void
cdc_ncm_find_endpoints(struct cdc_ncm_ctx *ctx, struct usb_interface *intf)
{
struct usb_host_endpoint *e;
u8 ep;
for (ep = 0; ep < intf->cur_altsetting->desc.bNumEndpoints; ep++) {
e = intf->cur_altsetting->endpoint + ep;
switch (e->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
case USB_ENDPOINT_XFER_INT:
if (usb_endpoint_dir_in(&e->desc)) {
if (ctx->status_ep == NULL)
ctx->status_ep = e;
}
break;
case USB_ENDPOINT_XFER_BULK:
if (usb_endpoint_dir_in(&e->desc)) {
if (ctx->in_ep == NULL)
ctx->in_ep = e;
} else {
if (ctx->out_ep == NULL)
ctx->out_ep = e;
}
break;
default:
break;
}
}
}
static void cdc_ncm_free(struct cdc_ncm_ctx *ctx)
{
if (ctx == NULL)
return;
if (ctx->tx_rem_skb != NULL) {
dev_kfree_skb_any(ctx->tx_rem_skb);
ctx->tx_rem_skb = NULL;
}
if (ctx->tx_curr_skb != NULL) {
dev_kfree_skb_any(ctx->tx_curr_skb);
ctx->tx_curr_skb = NULL;
}
kfree(ctx);
}
static const struct ethtool_ops cdc_ncm_ethtool_ops = {
.get_drvinfo = cdc_ncm_get_drvinfo,
.get_link = usbnet_get_link,
.get_msglevel = usbnet_get_msglevel,
.set_msglevel = usbnet_set_msglevel,
.get_settings = usbnet_get_settings,
.set_settings = usbnet_set_settings,
.nway_reset = usbnet_nway_reset,
};
int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_altsetting)
{
struct cdc_ncm_ctx *ctx;
struct usb_driver *driver;
u8 *buf;
int len;
int temp;
u8 iface_no;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
ctx->bh.data = (unsigned long)ctx;
ctx->bh.func = cdc_ncm_txpath_bh;
atomic_set(&ctx->stop, 0);
spin_lock_init(&ctx->mtx);
ctx->netdev = dev->net;
/* store ctx pointer in device data field */
dev->data[0] = (unsigned long)ctx;
/* get some pointers */
driver = driver_of(intf);
buf = intf->cur_altsetting->extra;
len = intf->cur_altsetting->extralen;
ctx->udev = dev->udev;
ctx->intf = intf;
/* parse through descriptors associated with control interface */
while ((len > 0) && (buf[0] > 2) && (buf[0] <= len)) {
if (buf[1] != USB_DT_CS_INTERFACE)
goto advance;
switch (buf[2]) {
case USB_CDC_UNION_TYPE:
if (buf[0] < sizeof(*(ctx->union_desc)))
break;
ctx->union_desc =
(const struct usb_cdc_union_desc *)buf;
ctx->control = usb_ifnum_to_if(dev->udev,
ctx->union_desc->bMasterInterface0);
ctx->data = usb_ifnum_to_if(dev->udev,
ctx->union_desc->bSlaveInterface0);
break;
case USB_CDC_ETHERNET_TYPE:
if (buf[0] < sizeof(*(ctx->ether_desc)))
break;
ctx->ether_desc =
(const struct usb_cdc_ether_desc *)buf;
dev->hard_mtu =
le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
if (dev->hard_mtu < CDC_NCM_MIN_DATAGRAM_SIZE)
dev->hard_mtu = CDC_NCM_MIN_DATAGRAM_SIZE;
else if (dev->hard_mtu > CDC_NCM_MAX_DATAGRAM_SIZE)
dev->hard_mtu = CDC_NCM_MAX_DATAGRAM_SIZE;
break;
case USB_CDC_NCM_TYPE:
if (buf[0] < sizeof(*(ctx->func_desc)))
break;
ctx->func_desc = (const struct usb_cdc_ncm_desc *)buf;
break;
case USB_CDC_MBIM_TYPE:
if (buf[0] < sizeof(*(ctx->mbim_desc)))
break;
ctx->mbim_desc = (const struct usb_cdc_mbim_desc *)buf;
break;
default:
break;
}
advance:
/* advance to next descriptor */
temp = buf[0];
buf += temp;
len -= temp;
}
/* some buggy devices have an IAD but no CDC Union */
if (!ctx->union_desc && intf->intf_assoc && intf->intf_assoc->bInterfaceCount == 2) {
ctx->control = intf;
ctx->data = usb_ifnum_to_if(dev->udev, intf->cur_altsetting->desc.bInterfaceNumber + 1);
dev_dbg(&intf->dev, "CDC Union missing - got slave from IAD\n");
}
/* check if we got everything */
if ((ctx->control == NULL) || (ctx->data == NULL) ||
((!ctx->mbim_desc) && ((ctx->ether_desc == NULL) || (ctx->control != intf))))
goto error;
/* claim data interface, if different from control */
if (ctx->data != ctx->control) {
temp = usb_driver_claim_interface(driver, ctx->data, dev);
if (temp)
goto error;
}
iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber;
/* reset data interface */
temp = usb_set_interface(dev->udev, iface_no, 0);
if (temp)
goto error2;
/* initialize data interface */
if (cdc_ncm_setup(ctx))
goto error2;
/* configure data interface */
temp = usb_set_interface(dev->udev, iface_no, data_altsetting);
if (temp)
goto error2;
cdc_ncm_find_endpoints(ctx, ctx->data);
cdc_ncm_find_endpoints(ctx, ctx->control);
if ((ctx->in_ep == NULL) || (ctx->out_ep == NULL) ||
(ctx->status_ep == NULL))
goto error2;
dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
usb_set_intfdata(ctx->data, dev);
usb_set_intfdata(ctx->control, dev);
usb_set_intfdata(ctx->intf, dev);
if (ctx->ether_desc) {
temp = usbnet_get_ethernet_addr(dev, ctx->ether_desc->iMACAddress);
if (temp)
goto error2;
dev_info(&dev->udev->dev, "MAC-Address: %pM\n", dev->net->dev_addr);
}
dev->in = usb_rcvbulkpipe(dev->udev,
ctx->in_ep->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
dev->out = usb_sndbulkpipe(dev->udev,
ctx->out_ep->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
dev->status = ctx->status_ep;
dev->rx_urb_size = ctx->rx_max;
ctx->tx_speed = ctx->rx_speed = 0;
return 0;
error2:
usb_set_intfdata(ctx->control, NULL);
usb_set_intfdata(ctx->data, NULL);
if (ctx->data != ctx->control)
usb_driver_release_interface(driver, ctx->data);
error:
cdc_ncm_free((struct cdc_ncm_ctx *)dev->data[0]);
dev->data[0] = 0;
dev_info(&dev->udev->dev, "bind() failure\n");
return -ENODEV;
}
EXPORT_SYMBOL_GPL(cdc_ncm_bind_common);
void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf)
{
struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
struct usb_driver *driver = driver_of(intf);
if (ctx == NULL)
return; /* no setup */
atomic_set(&ctx->stop, 1);
if (hrtimer_active(&ctx->tx_timer))
hrtimer_cancel(&ctx->tx_timer);
tasklet_kill(&ctx->bh);
/* handle devices with combined control and data interface */
if (ctx->control == ctx->data)
ctx->data = NULL;
/* disconnect master --> disconnect slave */
if (intf == ctx->control && ctx->data) {
usb_set_intfdata(ctx->data, NULL);
usb_driver_release_interface(driver, ctx->data);
ctx->data = NULL;
} else if (intf == ctx->data && ctx->control) {
usb_set_intfdata(ctx->control, NULL);
usb_driver_release_interface(driver, ctx->control);
ctx->control = NULL;
}
usb_set_intfdata(ctx->intf, NULL);
cdc_ncm_free(ctx);
}
EXPORT_SYMBOL_GPL(cdc_ncm_unbind);
/* Select the MBIM altsetting iff it is preferred and available,
* returning the number of the corresponding data interface altsetting
*/
u8 cdc_ncm_select_altsetting(struct usbnet *dev, struct usb_interface *intf)
{
struct usb_host_interface *alt;
/* The MBIM spec defines a NCM compatible default altsetting,
* which we may have matched:
*
* "Functions that implement both NCM 1.0 and MBIM (an
* “NCM/MBIM function”) according to this recommendation
* shall provide two alternate settings for the
* Communication Interface. Alternate setting 0, and the
* associated class and endpoint descriptors, shall be
* constructed according to the rules given for the
* Communication Interface in section 5 of [USBNCM10].
* Alternate setting 1, and the associated class and
* endpoint descriptors, shall be constructed according to
* the rules given in section 6 (USB Device Model) of this
* specification."
*/
if (prefer_mbim && intf->num_altsetting == 2) {
alt = usb_altnum_to_altsetting(intf, CDC_NCM_COMM_ALTSETTING_MBIM);
if (alt && cdc_ncm_comm_intf_is_mbim(alt) &&
!usb_set_interface(dev->udev,
intf->cur_altsetting->desc.bInterfaceNumber,
CDC_NCM_COMM_ALTSETTING_MBIM))
return CDC_NCM_DATA_ALTSETTING_MBIM;
}
return CDC_NCM_DATA_ALTSETTING_NCM;
}
EXPORT_SYMBOL_GPL(cdc_ncm_select_altsetting);
static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf)
{
int ret;
/* MBIM backwards compatible function? */
cdc_ncm_select_altsetting(dev, intf);
if (cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
return -ENODEV;
/* NCM data altsetting is always 1 */
ret = cdc_ncm_bind_common(dev, intf, 1);
/*
* We should get an event when network connection is "connected" or
* "disconnected". Set network connection in "disconnected" state
* (carrier is OFF) during attach, so the IP network stack does not
* start IPv6 negotiation and more.
*/
netif_carrier_off(dev->net);
return ret;
}
static void cdc_ncm_align_tail(struct sk_buff *skb, size_t modulus, size_t remainder, size_t max)
{
size_t align = ALIGN(skb->len, modulus) - skb->len + remainder;
if (skb->len + align > max)
align = max - skb->len;
if (align && skb_tailroom(skb) >= align)
memset(skb_put(skb, align), 0, align);
}
/* return a pointer to a valid struct usb_cdc_ncm_ndp16 of type sign, possibly
* allocating a new one within skb
*/
static struct usb_cdc_ncm_ndp16 *cdc_ncm_ndp(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign, size_t reserve)
{
struct usb_cdc_ncm_ndp16 *ndp16 = NULL;
struct usb_cdc_ncm_nth16 *nth16 = (void *)skb->data;
size_t ndpoffset = le16_to_cpu(nth16->wNdpIndex);
/* follow the chain of NDPs, looking for a match */
while (ndpoffset) {
ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb->data + ndpoffset);
if (ndp16->dwSignature == sign)
return ndp16;
ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
}
/* align new NDP */
cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_max);
/* verify that there is room for the NDP and the datagram (reserve) */
if ((ctx->tx_max - skb->len - reserve) < CDC_NCM_NDP_SIZE)
return NULL;
/* link to it */
if (ndp16)
ndp16->wNextNdpIndex = cpu_to_le16(skb->len);
else
nth16->wNdpIndex = cpu_to_le16(skb->len);
/* push a new empty NDP */
ndp16 = (struct usb_cdc_ncm_ndp16 *)memset(skb_put(skb, CDC_NCM_NDP_SIZE), 0, CDC_NCM_NDP_SIZE);
ndp16->dwSignature = sign;
ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16) + sizeof(struct usb_cdc_ncm_dpe16));
return ndp16;
}
struct sk_buff *
cdc_ncm_fill_tx_frame(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign)
{
struct usb_cdc_ncm_nth16 *nth16;
struct usb_cdc_ncm_ndp16 *ndp16;
struct sk_buff *skb_out;
u16 n = 0, index, ndplen;
u8 ready2send = 0;
/* if there is a remaining skb, it gets priority */
if (skb != NULL) {
swap(skb, ctx->tx_rem_skb);
swap(sign, ctx->tx_rem_sign);
} else {
ready2send = 1;
}
/* check if we are resuming an OUT skb */
skb_out = ctx->tx_curr_skb;
/* allocate a new OUT skb */
if (!skb_out) {
skb_out = alloc_skb((ctx->tx_max + 1), GFP_ATOMIC);
if (skb_out == NULL) {
if (skb != NULL) {
dev_kfree_skb_any(skb);
ctx->netdev->stats.tx_dropped++;
}
goto exit_no_skb;
}
/* fill out the initial 16-bit NTB header */
nth16 = (struct usb_cdc_ncm_nth16 *)memset(skb_put(skb_out, sizeof(struct usb_cdc_ncm_nth16)), 0, sizeof(struct usb_cdc_ncm_nth16));
nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
nth16->wSequence = cpu_to_le16(ctx->tx_seq++);
/* count total number of frames in this NTB */
ctx->tx_curr_frame_num = 0;
}
for (n = ctx->tx_curr_frame_num; n < ctx->tx_max_datagrams; n++) {
/* send any remaining skb first */
if (skb == NULL) {
skb = ctx->tx_rem_skb;
sign = ctx->tx_rem_sign;
ctx->tx_rem_skb = NULL;
/* check for end of skb */
if (skb == NULL)
break;
}
/* get the appropriate NDP for this skb */
ndp16 = cdc_ncm_ndp(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
/* align beginning of next frame */
cdc_ncm_align_tail(skb_out, ctx->tx_modulus, ctx->tx_remainder, ctx->tx_max);
/* check if we had enough room left for both NDP and frame */
if (!ndp16 || skb_out->len + skb->len > ctx->tx_max) {
if (n == 0) {
/* won't fit, MTU problem? */
dev_kfree_skb_any(skb);
skb = NULL;
ctx->netdev->stats.tx_dropped++;
} else {
/* no room for skb - store for later */
if (ctx->tx_rem_skb != NULL) {
dev_kfree_skb_any(ctx->tx_rem_skb);
ctx->netdev->stats.tx_dropped++;
}
ctx->tx_rem_skb = skb;
ctx->tx_rem_sign = sign;
skb = NULL;
ready2send = 1;
}
break;
}
/* calculate frame number withing this NDP */
ndplen = le16_to_cpu(ndp16->wLength);
index = (ndplen - sizeof(struct usb_cdc_ncm_ndp16)) / sizeof(struct usb_cdc_ncm_dpe16) - 1;
/* OK, add this skb */
ndp16->dpe16[index].wDatagramLength = cpu_to_le16(skb->len);
ndp16->dpe16[index].wDatagramIndex = cpu_to_le16(skb_out->len);
ndp16->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe16));
memcpy(skb_put(skb_out, skb->len), skb->data, skb->len);
dev_kfree_skb_any(skb);
skb = NULL;
/* send now if this NDP is full */
if (index >= CDC_NCM_DPT_DATAGRAMS_MAX) {
ready2send = 1;
break;
}
}
/* free up any dangling skb */
if (skb != NULL) {
dev_kfree_skb_any(skb);
skb = NULL;
ctx->netdev->stats.tx_dropped++;
}
ctx->tx_curr_frame_num = n;
if (n == 0) {
/* wait for more frames */
/* push variables */
ctx->tx_curr_skb = skb_out;
goto exit_no_skb;
} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0)) {
/* wait for more frames */
/* push variables */
ctx->tx_curr_skb = skb_out;
/* set the pending count */
if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
ctx->tx_timer_pending = CDC_NCM_TIMER_PENDING_CNT;
goto exit_no_skb;
} else {
/* frame goes out */
/* variables will be reset at next call */
}
/*
* If collected data size is less or equal CDC_NCM_MIN_TX_PKT bytes,
* we send buffers as it is. If we get more data, it would be more
* efficient for USB HS mobile device with DMA engine to receive a full
* size NTB, than canceling DMA transfer and receiving a short packet.
*/
if (skb_out->len > CDC_NCM_MIN_TX_PKT)
/* final zero padding */
memset(skb_put(skb_out, ctx->tx_max - skb_out->len), 0, ctx->tx_max - skb_out->len);
/* do we need to prevent a ZLP? */
if (((skb_out->len % le16_to_cpu(ctx->out_ep->desc.wMaxPacketSize)) == 0) &&
(skb_out->len < le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize)) && skb_tailroom(skb_out))
*skb_put(skb_out, 1) = 0; /* force short packet */
/* set final frame length */
nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
nth16->wBlockLength = cpu_to_le16(skb_out->len);
/* return skb */
ctx->tx_curr_skb = NULL;
ctx->netdev->stats.tx_packets += ctx->tx_curr_frame_num;
return skb_out;
exit_no_skb:
/* Start timer, if there is a remaining skb */
if (ctx->tx_curr_skb != NULL)
cdc_ncm_tx_timeout_start(ctx);
return NULL;
}
EXPORT_SYMBOL_GPL(cdc_ncm_fill_tx_frame);
static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx)
{
/* start timer, if not already started */
if (!(hrtimer_active(&ctx->tx_timer) || atomic_read(&ctx->stop)))
hrtimer_start(&ctx->tx_timer,
ktime_set(0, CDC_NCM_TIMER_INTERVAL),
HRTIMER_MODE_REL);
}
static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
{
struct cdc_ncm_ctx *ctx =
container_of(timer, struct cdc_ncm_ctx, tx_timer);
if (!atomic_read(&ctx->stop))
tasklet_schedule(&ctx->bh);
return HRTIMER_NORESTART;
}
static void cdc_ncm_txpath_bh(unsigned long param)
{
struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)param;
spin_lock_bh(&ctx->mtx);
if (ctx->tx_timer_pending != 0) {
ctx->tx_timer_pending--;
cdc_ncm_tx_timeout_start(ctx);
spin_unlock_bh(&ctx->mtx);
} else if (ctx->netdev != NULL) {
spin_unlock_bh(&ctx->mtx);
netif_tx_lock_bh(ctx->netdev);
usbnet_start_xmit(NULL, ctx->netdev);
netif_tx_unlock_bh(ctx->netdev);
} else {
spin_unlock_bh(&ctx->mtx);
}
}
static struct sk_buff *
cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
{
struct sk_buff *skb_out;
struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
/*
* The Ethernet API we are using does not support transmitting
* multiple Ethernet frames in a single call. This driver will
* accumulate multiple Ethernet frames and send out a larger
* USB frame when the USB buffer is full or when a single jiffies
* timeout happens.
*/
if (ctx == NULL)
goto error;
spin_lock_bh(&ctx->mtx);
skb_out = cdc_ncm_fill_tx_frame(ctx, skb, cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN));
spin_unlock_bh(&ctx->mtx);
return skb_out;
error:
if (skb != NULL)
dev_kfree_skb_any(skb);
return NULL;
}
/* verify NTB header and return offset of first NDP, or negative error */
int cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in)
{
struct usb_cdc_ncm_nth16 *nth16;
int len;
int ret = -EINVAL;
if (ctx == NULL)
goto error;
if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth16) +
sizeof(struct usb_cdc_ncm_ndp16))) {
pr_debug("frame too short\n");
goto error;
}
nth16 = (struct usb_cdc_ncm_nth16 *)skb_in->data;
if (le32_to_cpu(nth16->dwSignature) != USB_CDC_NCM_NTH16_SIGN) {
pr_debug("invalid NTH16 signature <%u>\n",
le32_to_cpu(nth16->dwSignature));
goto error;
}
len = le16_to_cpu(nth16->wBlockLength);
if (len > ctx->rx_max) {
pr_debug("unsupported NTB block length %u/%u\n", len,
ctx->rx_max);
goto error;
}
if ((ctx->rx_seq + 1) != le16_to_cpu(nth16->wSequence) &&
(ctx->rx_seq || le16_to_cpu(nth16->wSequence)) &&
!((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth16->wSequence))) {
pr_debug("sequence number glitch prev=%d curr=%d\n",
ctx->rx_seq, le16_to_cpu(nth16->wSequence));
}
ctx->rx_seq = le16_to_cpu(nth16->wSequence);
ret = le16_to_cpu(nth16->wNdpIndex);
error:
return ret;
}
EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_nth16);
/* verify NDP header and return number of datagrams, or negative error */
int cdc_ncm_rx_verify_ndp16(struct sk_buff *skb_in, int ndpoffset)
{
struct usb_cdc_ncm_ndp16 *ndp16;
int ret = -EINVAL;
if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) {
pr_debug("invalid NDP offset <%u>\n", ndpoffset);
goto error;
}
ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) {
pr_debug("invalid DPT16 length <%u>\n",
le32_to_cpu(ndp16->dwSignature));
goto error;
}
ret = ((le16_to_cpu(ndp16->wLength) -
sizeof(struct usb_cdc_ncm_ndp16)) /
sizeof(struct usb_cdc_ncm_dpe16));
ret--; /* we process NDP entries except for the last one */
if ((sizeof(struct usb_cdc_ncm_ndp16) + ret * (sizeof(struct usb_cdc_ncm_dpe16))) >
skb_in->len) {
pr_debug("Invalid nframes = %d\n", ret);
ret = -EINVAL;
}
error:
return ret;
}
EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_ndp16);
static int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
{
struct sk_buff *skb;
struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
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 */
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);
if (le32_to_cpu(ndp16->dwSignature) != USB_CDC_NCM_NDP16_NOCRC_SIGN) {
pr_debug("invalid DPT16 signature <%u>\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) || (len < ETH_HLEN)) {
pr_debug("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 = skb_clone(skb_in, GFP_ATOMIC);
if (!skb)
goto error;
skb->len = len;
skb->data = ((u8 *)skb_in->data) + offset;
skb_set_tail_pointer(skb, len);
usbnet_skb_return(dev, skb);
}
}
err_ndp:
/* are there more NDPs to process? */
ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
if (ndpoffset && loopcount--)
goto next_ndp;
return 1;
error:
return 0;
}
static void
cdc_ncm_speed_change(struct cdc_ncm_ctx *ctx,
struct usb_cdc_speed_change *data)
{
uint32_t rx_speed = le32_to_cpu(data->DLBitRRate);
uint32_t tx_speed = le32_to_cpu(data->ULBitRate);
/*
* Currently the USB-NET API does not support reporting the actual
* device speed. Do print it instead.
*/
if ((tx_speed != ctx->tx_speed) || (rx_speed != ctx->rx_speed)) {
ctx->tx_speed = tx_speed;
ctx->rx_speed = rx_speed;
if ((tx_speed > 1000000) && (rx_speed > 1000000)) {
printk(KERN_INFO KBUILD_MODNAME
": %s: %u mbit/s downlink "
"%u mbit/s uplink\n",
ctx->netdev->name,
(unsigned int)(rx_speed / 1000000U),
(unsigned int)(tx_speed / 1000000U));
} else {
printk(KERN_INFO KBUILD_MODNAME
": %s: %u kbit/s downlink "
"%u kbit/s uplink\n",
ctx->netdev->name,
(unsigned int)(rx_speed / 1000U),
(unsigned int)(tx_speed / 1000U));
}
}
}
static void cdc_ncm_status(struct usbnet *dev, struct urb *urb)
{
struct cdc_ncm_ctx *ctx;
struct usb_cdc_notification *event;
ctx = (struct cdc_ncm_ctx *)dev->data[0];
if (urb->actual_length < sizeof(*event))
return;
/* test for split data in 8-byte chunks */
if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
cdc_ncm_speed_change(ctx,
(struct usb_cdc_speed_change *)urb->transfer_buffer);
return;
}
event = urb->transfer_buffer;
switch (event->bNotificationType) {
case USB_CDC_NOTIFY_NETWORK_CONNECTION:
/*
* According to the CDC NCM specification ch.7.1
* USB_CDC_NOTIFY_NETWORK_CONNECTION notification shall be
* sent by device after USB_CDC_NOTIFY_SPEED_CHANGE.
*/
ctx->connected = le16_to_cpu(event->wValue);
printk(KERN_INFO KBUILD_MODNAME ": %s: network connection:"
" %sconnected\n",
ctx->netdev->name, ctx->connected ? "" : "dis");
if (ctx->connected)
netif_carrier_on(dev->net);
else {
netif_carrier_off(dev->net);
ctx->tx_speed = ctx->rx_speed = 0;
}
break;
case USB_CDC_NOTIFY_SPEED_CHANGE:
if (urb->actual_length < (sizeof(*event) +
sizeof(struct usb_cdc_speed_change)))
set_bit(EVENT_STS_SPLIT, &dev->flags);
else
cdc_ncm_speed_change(ctx,
(struct usb_cdc_speed_change *) &event[1]);
break;
default:
dev_dbg(&dev->udev->dev,
"NCM: unexpected notification 0x%02x!\n",
event->bNotificationType);
break;
}
}
static int cdc_ncm_check_connect(struct usbnet *dev)
{
struct cdc_ncm_ctx *ctx;
ctx = (struct cdc_ncm_ctx *)dev->data[0];
if (ctx == NULL)
return 1; /* disconnected */
return !ctx->connected;
}
static int
cdc_ncm_probe(struct usb_interface *udev, const struct usb_device_id *prod)
{
return usbnet_probe(udev, prod);
}
static void cdc_ncm_disconnect(struct usb_interface *intf)
{
struct usbnet *dev = usb_get_intfdata(intf);
if (dev == NULL)
return; /* already disconnected */
usbnet_disconnect(intf);
}
static const struct driver_info cdc_ncm_info = {
.description = "CDC NCM",
.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET,
.bind = cdc_ncm_bind,
.unbind = cdc_ncm_unbind,
.check_connect = cdc_ncm_check_connect,
.manage_power = usbnet_manage_power,
.status = cdc_ncm_status,
.rx_fixup = cdc_ncm_rx_fixup,
.tx_fixup = cdc_ncm_tx_fixup,
};
/* Same as cdc_ncm_info, but with FLAG_WWAN */
static const struct driver_info wwan_info = {
.description = "Mobile Broadband Network Device",
.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
| FLAG_WWAN,
.bind = cdc_ncm_bind,
.unbind = cdc_ncm_unbind,
.check_connect = cdc_ncm_check_connect,
.manage_power = usbnet_manage_power,
.status = cdc_ncm_status,
.rx_fixup = cdc_ncm_rx_fixup,
.tx_fixup = cdc_ncm_tx_fixup,
};
/* Same as wwan_info, but with FLAG_NOARP */
static const struct driver_info wwan_noarp_info = {
.description = "Mobile Broadband Network Device (NO ARP)",
.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
| FLAG_WWAN | FLAG_NOARP,
.bind = cdc_ncm_bind,
.unbind = cdc_ncm_unbind,
.check_connect = cdc_ncm_check_connect,
.manage_power = usbnet_manage_power,
.status = cdc_ncm_status,
.rx_fixup = cdc_ncm_rx_fixup,
.tx_fixup = cdc_ncm_tx_fixup,
};
static const struct usb_device_id cdc_devs[] = {
/* Ericsson MBM devices like F5521gw */
{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
| USB_DEVICE_ID_MATCH_VENDOR,
.idVendor = 0x0bdb,
.bInterfaceClass = USB_CLASS_COMM,
.bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
.bInterfaceProtocol = USB_CDC_PROTO_NONE,
.driver_info = (unsigned long) &wwan_info,
},
/* Dell branded MBM devices like DW5550 */
{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
| USB_DEVICE_ID_MATCH_VENDOR,
.idVendor = 0x413c,
.bInterfaceClass = USB_CLASS_COMM,
.bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
.bInterfaceProtocol = USB_CDC_PROTO_NONE,
.driver_info = (unsigned long) &wwan_info,
},
/* Toshiba branded MBM devices */
{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
| USB_DEVICE_ID_MATCH_VENDOR,
.idVendor = 0x0930,
.bInterfaceClass = USB_CLASS_COMM,
.bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
.bInterfaceProtocol = USB_CDC_PROTO_NONE,
.driver_info = (unsigned long) &wwan_info,
},
/* tag Huawei devices as wwan */
{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1,
USB_CLASS_COMM,
USB_CDC_SUBCLASS_NCM,
USB_CDC_PROTO_NONE),
.driver_info = (unsigned long)&wwan_info,
},
/* Huawei NCM devices disguised as vendor specific */
{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1, 0xff, 0x02, 0x16),
.driver_info = (unsigned long)&wwan_info,
},
{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1, 0xff, 0x02, 0x46),
.driver_info = (unsigned long)&wwan_info,
},
{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1, 0xff, 0x02, 0x76),
.driver_info = (unsigned long)&wwan_info,
},
/* Infineon(now Intel) HSPA Modem platform */
{ USB_DEVICE_AND_INTERFACE_INFO(0x1519, 0x0443,
USB_CLASS_COMM,
USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
.driver_info = (unsigned long)&wwan_noarp_info,
},
/* Generic CDC-NCM devices */
{ USB_INTERFACE_INFO(USB_CLASS_COMM,
USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
.driver_info = (unsigned long)&cdc_ncm_info,
},
{
},
};
MODULE_DEVICE_TABLE(usb, cdc_devs);
static struct usb_driver cdc_ncm_driver = {
.name = "cdc_ncm",
.id_table = cdc_devs,
.probe = cdc_ncm_probe,
.disconnect = cdc_ncm_disconnect,
.suspend = usbnet_suspend,
.resume = usbnet_resume,
.reset_resume = usbnet_resume,
.supports_autosuspend = 1,
.disable_hub_initiated_lpm = 1,
};
module_usb_driver(cdc_ncm_driver);
MODULE_AUTHOR("Hans Petter Selasky");
MODULE_DESCRIPTION("USB CDC NCM host driver");
MODULE_LICENSE("Dual BSD/GPL");