/*
* f_rndis.c -- RNDIS link function driver
*
* Copyright (C) 2003-2005,2008 David Brownell
* Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
* Copyright (C) 2008 Nokia Corporation
*
* 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
*/
/* #define VERBOSE_DEBUG */
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/etherdevice.h>
#include <asm/atomic.h>
#include "u_ether.h"
#include "rndis.h"
/*
* This function is an RNDIS Ethernet port -- a Microsoft protocol that's
* been promoted instead of the standard CDC Ethernet. The published RNDIS
* spec is ambiguous, incomplete, and needlessly complex. Variants such as
* ActiveSync have even worse status in terms of specification.
*
* In short: it's a protocol controlled by (and for) Microsoft, not for an
* Open ecosystem or markets. Linux supports it *only* because Microsoft
* doesn't support the CDC Ethernet standard.
*
* The RNDIS data transfer model is complex, with multiple Ethernet packets
* per USB message, and out of band data. The control model is built around
* what's essentially an "RNDIS RPC" protocol. It's all wrapped in a CDC ACM
* (modem, not Ethernet) veneer, with those ACM descriptors being entirely
* useless (they're ignored). RNDIS expects to be the only function in its
* configuration, so it's no real help if you need composite devices; and
* it expects to be the first configuration too.
*
* There is a single technical advantage of RNDIS over CDC Ethernet, if you
* discount the fluff that its RPC can be made to deliver: it doesn't need
* a NOP altsetting for the data interface. That lets it work on some of the
* "so smart it's stupid" hardware which takes over configuration changes
* from the software, and adds restrictions like "no altsettings".
*
* Unfortunately MSFT's RNDIS drivers are buggy. They hang or oops, and
* have all sorts of contrary-to-specification oddities that can prevent
* them from working sanely. Since bugfixes (or accurate specs, letting
* Linux work around those bugs) are unlikely to ever come from MSFT, you
* may want to avoid using RNDIS on purely operational grounds.
*
* Omissions from the RNDIS 1.0 specification include:
*
* - Power management ... references data that's scattered around lots
* of other documentation, which is incorrect/incomplete there too.
*
* - There are various undocumented protocol requirements, like the need
* to send garbage in some control-OUT messages.
*
* - MS-Windows drivers sometimes emit undocumented requests.
*/
struct rndis_ep_descs {
struct usb_endpoint_descriptor *in;
struct usb_endpoint_descriptor *out;
struct usb_endpoint_descriptor *notify;
};
struct f_rndis {
struct gether port;
u8 ctrl_id, data_id;
u8 ethaddr[ETH_ALEN];
int config;
struct rndis_ep_descs fs;
struct rndis_ep_descs hs;
struct usb_ep *notify;
struct usb_endpoint_descriptor *notify_desc;
struct usb_request *notify_req;
atomic_t notify_count;
};
static inline struct f_rndis *func_to_rndis(struct usb_function *f)
{
return container_of(f, struct f_rndis, port.func);
}
/* peak (theoretical) bulk transfer rate in bits-per-second */
static unsigned int bitrate(struct usb_gadget *g)
{
if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
return 13 * 512 * 8 * 1000 * 8;
else
return 19 * 64 * 1 * 1000 * 8;
}
/*-------------------------------------------------------------------------*/
/*
*/
#define LOG2_STATUS_INTERVAL_MSEC 5 /* 1 << 5 == 32 msec */
#define STATUS_BYTECOUNT 8 /* 8 bytes data */
/* interface descriptor: */
static struct usb_interface_descriptor rndis_control_intf __initdata = {
.bLength = sizeof rndis_control_intf,
.bDescriptorType = USB_DT_INTERFACE,
/* .bInterfaceNumber = DYNAMIC */
/* status endpoint is optional; this could be patched later */
.bNumEndpoints = 1,
.bInterfaceClass = USB_CLASS_COMM,
.bInterfaceSubClass = USB_CDC_SUBCLASS_ACM,
.bInterfaceProtocol = USB_CDC_ACM_PROTO_VENDOR,
/* .iInterface = DYNAMIC */
};
static struct usb_cdc_header_desc header_desc __initdata = {
.bLength = sizeof header_desc,
.bDescriptorType = USB_DT_CS_INTERFACE,
.bDescriptorSubType = USB_CDC_HEADER_TYPE,
.bcdCDC = __constant_cpu_to_le16(0x0110),
};
static struct usb_cdc_call_mgmt_descriptor call_mgmt_descriptor __initdata = {
.bLength = sizeof call_mgmt_descriptor,
.bDescriptorType = USB_DT_CS_INTERFACE,
.bDescriptorSubType = USB_CDC_CALL_MANAGEMENT_TYPE,
.bmCapabilities = 0x00,
.bDataInterface = 0x01,
};
static struct usb_cdc_acm_descriptor acm_descriptor __initdata = {
.bLength = sizeof acm_descriptor,
.bDescriptorType = USB_DT_CS_INTERFACE,
.bDescriptorSubType = USB_CDC_ACM_TYPE,
.bmCapabilities = 0x00,
};
static struct usb_cdc_union_desc rndis_union_desc __initdata = {
.bLength = sizeof(rndis_union_desc),
.bDescriptorType = USB_DT_CS_INTERFACE,
.bDescriptorSubType = USB_CDC_UNION_TYPE,
/* .bMasterInterface0 = DYNAMIC */
/* .bSlaveInterface0 = DYNAMIC */
};
/* the data interface has two bulk endpoints */
static struct usb_interface_descriptor rndis_data_intf __initdata = {
.bLength = sizeof rndis_data_intf,
.bDescriptorType = USB_DT_INTERFACE,
/* .bInterfaceNumber = DYNAMIC */
.bNumEndpoints = 2,
.bInterfaceClass = USB_CLASS_CDC_DATA,
.bInterfaceSubClass = 0,
.bInterfaceProtocol = 0,
/* .iInterface = DYNAMIC */
};
/* full speed support: */
static struct usb_endpoint_descriptor fs_notify_desc __initdata = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = __constant_cpu_to_le16(STATUS_BYTECOUNT),
.bInterval = 1 << LOG2_STATUS_INTERVAL_MSEC,
};
static struct usb_endpoint_descriptor fs_in_desc __initdata = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
};
static struct usb_endpoint_descriptor fs_out_desc __initdata = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
};
static struct usb_descriptor_header *eth_fs_function[] __initdata = {
/* control interface matches ACM, not Ethernet */
(struct usb_descriptor_header *) &rndis_control_intf,
(struct usb_descriptor_header *) &header_desc,
(struct usb_descriptor_header *) &call_mgmt_descriptor,
(struct usb_descriptor_header *) &acm_descriptor,
(struct usb_descriptor_header *) &rndis_union_desc,
(struct usb_descriptor_header *) &fs_notify_desc,
/* data interface has no altsetting */
(struct usb_descriptor_header *) &rndis_data_intf,
(struct usb_descriptor_header *) &fs_in_desc,
(struct usb_descriptor_header *) &fs_out_desc,
NULL,
};
/* high speed support: */
static struct usb_endpoint_descriptor hs_notify_desc __initdata = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_INT,
.wMaxPacketSize = __constant_cpu_to_le16(STATUS_BYTECOUNT),
.bInterval = LOG2_STATUS_INTERVAL_MSEC + 4,
};
static struct usb_endpoint_descriptor hs_in_desc __initdata = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = __constant_cpu_to_le16(512),
};
static struct usb_endpoint_descriptor hs_out_desc __initdata = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = __constant_cpu_to_le16(512),
};
static struct usb_descriptor_header *eth_hs_function[] __initdata = {
/* control interface matches ACM, not Ethernet */
(struct usb_descriptor_header *) &rndis_control_intf,
(struct usb_descriptor_header *) &header_desc,
(struct usb_descriptor_header *) &call_mgmt_descriptor,
(struct usb_descriptor_header *) &acm_descriptor,
(struct usb_descriptor_header *) &rndis_union_desc,
(struct usb_descriptor_header *) &hs_notify_desc,
/* data interface has no altsetting */
(struct usb_descriptor_header *) &rndis_data_intf,
(struct usb_descriptor_header *) &hs_in_desc,
(struct usb_descriptor_header *) &hs_out_desc,
NULL,
};
/* string descriptors: */
static struct usb_string rndis_string_defs[] = {
[0].s = "RNDIS Communications Control",
[1].s = "RNDIS Ethernet Data",
{ } /* end of list */
};
static struct usb_gadget_strings rndis_string_table = {
.language = 0x0409, /* en-us */
.strings = rndis_string_defs,
};
static struct usb_gadget_strings *rndis_strings[] = {
&rndis_string_table,
NULL,
};
/*-------------------------------------------------------------------------*/
static struct sk_buff *rndis_add_header(struct sk_buff *skb)
{
skb = skb_realloc_headroom(skb, sizeof(struct rndis_packet_msg_type));
if (skb)
rndis_add_hdr(skb);
return skb;
}
static void rndis_response_available(void *_rndis)
{
struct f_rndis *rndis = _rndis;
struct usb_request *req = rndis->notify_req;
struct usb_composite_dev *cdev = rndis->port.func.config->cdev;
__le32 *data = req->buf;
int status;
if (atomic_inc_return(&rndis->notify_count) != 1)
return;
/* Send RNDIS RESPONSE_AVAILABLE notification; a
* USB_CDC_NOTIFY_RESPONSE_AVAILABLE "should" work too
*
* This is the only notification defined by RNDIS.
*/
data[0] = cpu_to_le32(1);
data[1] = cpu_to_le32(0);
status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC);
if (status) {
atomic_dec(&rndis->notify_count);
DBG(cdev, "notify/0 --> %d\n", status);
}
}
static void rndis_response_complete(struct usb_ep *ep, struct usb_request *req)
{
struct f_rndis *rndis = req->context;
struct usb_composite_dev *cdev = rndis->port.func.config->cdev;
int status = req->status;
/* after TX:
* - USB_CDC_GET_ENCAPSULATED_RESPONSE (ep0/control)
* - RNDIS_RESPONSE_AVAILABLE (status/irq)
*/
switch (status) {
case -ECONNRESET:
case -ESHUTDOWN:
/* connection gone */
atomic_set(&rndis->notify_count, 0);
break;
default:
DBG(cdev, "RNDIS %s response error %d, %d/%d\n",
ep->name, status,
req->actual, req->length);
/* FALLTHROUGH */
case 0:
if (ep != rndis->notify)
break;
/* handle multiple pending RNDIS_RESPONSE_AVAILABLE
* notifications by resending until we're done
*/
if (atomic_dec_and_test(&rndis->notify_count))
break;
status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC);
if (status) {
atomic_dec(&rndis->notify_count);
DBG(cdev, "notify/1 --> %d\n", status);
}
break;
}
}
static void rndis_command_complete(struct usb_ep *ep, struct usb_request *req)
{
struct f_rndis *rndis = req->context;
struct usb_composite_dev *cdev = rndis->port.func.config->cdev;
int status;
/* received RNDIS command from USB_CDC_SEND_ENCAPSULATED_COMMAND */
// spin_lock(&dev->lock);
status = rndis_msg_parser(rndis->config, (u8 *) req->buf);
if (status < 0)
ERROR(cdev, "RNDIS command error %d, %d/%d\n",
status, req->actual, req->length);
// spin_unlock(&dev->lock);
}
static int
rndis_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
{
struct f_rndis *rndis = func_to_rndis(f);
struct usb_composite_dev *cdev = f->config->cdev;
struct usb_request *req = cdev->req;
int value = -EOPNOTSUPP;
u16 w_index = le16_to_cpu(ctrl->wIndex);
u16 w_value = le16_to_cpu(ctrl->wValue);
u16 w_length = le16_to_cpu(ctrl->wLength);
/* composite driver infrastructure handles everything except
* CDC class messages; interface activation uses set_alt().
*/
switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
/* RNDIS uses the CDC command encapsulation mechanism to implement
* an RPC scheme, with much getting/setting of attributes by OID.
*/
case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
| USB_CDC_SEND_ENCAPSULATED_COMMAND:
if (w_length > req->length || w_value
|| w_index != rndis->ctrl_id)
goto invalid;
/* read the request; process it later */
value = w_length;
req->complete = rndis_command_complete;
req->context = rndis;
/* later, rndis_response_available() sends a notification */
break;
case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
| USB_CDC_GET_ENCAPSULATED_RESPONSE:
if (w_value || w_index != rndis->ctrl_id)
goto invalid;
else {
u8 *buf;
u32 n;
/* return the result */
buf = rndis_get_next_response(rndis->config, &n);
if (buf) {
memcpy(req->buf, buf, n);
req->complete = rndis_response_complete;
rndis_free_response(rndis->config, buf);
value = n;
}
/* else stalls ... spec says to avoid that */
}
break;
default:
invalid:
VDBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
ctrl->bRequestType, ctrl->bRequest,
w_value, w_index, w_length);
}
/* respond with data transfer or status phase? */
if (value >= 0) {
DBG(cdev, "rndis req%02x.%02x v%04x i%04x l%d\n",
ctrl->bRequestType, ctrl->bRequest,
w_value, w_index, w_length);
req->zero = 0;
req->length = value;
value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
if (value < 0)
ERROR(cdev, "rndis response on err %d\n", value);
}
/* device either stalls (value < 0) or reports success */
return value;
}
static int rndis_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
{
struct f_rndis *rndis = func_to_rndis(f);
struct usb_composite_dev *cdev = f->config->cdev;
/* we know alt == 0 */
if (intf == rndis->ctrl_id) {
if (rndis->notify->driver_data) {
VDBG(cdev, "reset rndis control %d\n", intf);
usb_ep_disable(rndis->notify);
} else {
VDBG(cdev, "init rndis ctrl %d\n", intf);
rndis->notify_desc = ep_choose(cdev->gadget,
rndis->hs.notify,
rndis->fs.notify);
}
usb_ep_enable(rndis->notify, rndis->notify_desc);
rndis->notify->driver_data = rndis;
} else if (intf == rndis->data_id) {
struct net_device *net;
if (rndis->port.in_ep->driver_data) {
DBG(cdev, "reset rndis\n");
gether_disconnect(&rndis->port);
} else {
DBG(cdev, "init rndis\n");
rndis->port.in = ep_choose(cdev->gadget,
rndis->hs.in, rndis->fs.in);
rndis->port.out = ep_choose(cdev->gadget,
rndis->hs.out, rndis->fs.out);
}
/* Avoid ZLPs; they can be troublesome. */
rndis->port.is_zlp_ok = false;
/* RNDIS should be in the "RNDIS uninitialized" state,
* either never activated or after rndis_uninit().
*
* We don't want data to flow here until a nonzero packet
* filter is set, at which point it enters "RNDIS data
* initialized" state ... but we do want the endpoints
* to be activated. It's a strange little state.
*
* REVISIT the RNDIS gadget code has done this wrong for a
* very long time. We need another call to the link layer
* code -- gether_updown(...bool) maybe -- to do it right.
*/
rndis->port.cdc_filter = 0;
DBG(cdev, "RNDIS RX/TX early activation ... \n");
net = gether_connect(&rndis->port);
if (IS_ERR(net))
return PTR_ERR(net);
rndis_set_param_dev(rndis->config, net,
&rndis->port.cdc_filter);
} else
goto fail;
return 0;
fail:
return -EINVAL;
}
static void rndis_disable(struct usb_function *f)
{
struct f_rndis *rndis = func_to_rndis(f);
struct usb_composite_dev *cdev = f->config->cdev;
if (!rndis->notify->driver_data)
return;
DBG(cdev, "rndis deactivated\n");
rndis_uninit(rndis->config);
gether_disconnect(&rndis->port);
usb_ep_disable(rndis->notify);
rndis->notify->driver_data = NULL;
}
/*-------------------------------------------------------------------------*/
/*
* This isn't quite the same mechanism as CDC Ethernet, since the
* notification scheme passes less data, but the same set of link
* states must be tested. A key difference is that altsettings are
* not used to tell whether the link should send packets or not.
*/
static void rndis_open(struct gether *geth)
{
struct f_rndis *rndis = func_to_rndis(&geth->func);
struct usb_composite_dev *cdev = geth->func.config->cdev;
DBG(cdev, "%s\n", __func__);
rndis_set_param_medium(rndis->config, NDIS_MEDIUM_802_3,
bitrate(cdev->gadget) / 100);
rndis_signal_connect(rndis->config);
}
static void rndis_close(struct gether *geth)
{
struct f_rndis *rndis = func_to_rndis(&geth->func);
DBG(geth->func.config->cdev, "%s\n", __func__);
rndis_set_param_medium(rndis->config, NDIS_MEDIUM_802_3, 0);
rndis_signal_disconnect(rndis->config);
}
/*-------------------------------------------------------------------------*/
/* ethernet function driver setup/binding */
static int __init
rndis_bind(struct usb_configuration *c, struct usb_function *f)
{
struct usb_composite_dev *cdev = c->cdev;
struct f_rndis *rndis = func_to_rndis(f);
int status;
struct usb_ep *ep;
/* allocate instance-specific interface IDs */
status = usb_interface_id(c, f);
if (status < 0)
goto fail;
rndis->ctrl_id = status;
rndis_control_intf.bInterfaceNumber = status;
rndis_union_desc.bMasterInterface0 = status;
status = usb_interface_id(c, f);
if (status < 0)
goto fail;
rndis->data_id = status;
rndis_data_intf.bInterfaceNumber = status;
rndis_union_desc.bSlaveInterface0 = status;
status = -ENODEV;
/* allocate instance-specific endpoints */
ep = usb_ep_autoconfig(cdev->gadget, &fs_in_desc);
if (!ep)
goto fail;
rndis->port.in_ep = ep;
ep->driver_data = cdev; /* claim */
ep = usb_ep_autoconfig(cdev->gadget, &fs_out_desc);
if (!ep)
goto fail;
rndis->port.out_ep = ep;
ep->driver_data = cdev; /* claim */
/* NOTE: a status/notification endpoint is, strictly speaking,
* optional. We don't treat it that way though! It's simpler,
* and some newer profiles don't treat it as optional.
*/
ep = usb_ep_autoconfig(cdev->gadget, &fs_notify_desc);
if (!ep)
goto fail;
rndis->notify = ep;
ep->driver_data = cdev; /* claim */
status = -ENOMEM;
/* allocate notification request and buffer */
rndis->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
if (!rndis->notify_req)
goto fail;
rndis->notify_req->buf = kmalloc(STATUS_BYTECOUNT, GFP_KERNEL);
if (!rndis->notify_req->buf)
goto fail;
rndis->notify_req->length = STATUS_BYTECOUNT;
rndis->notify_req->context = rndis;
rndis->notify_req->complete = rndis_response_complete;
/* copy descriptors, and track endpoint copies */
f->descriptors = usb_copy_descriptors(eth_fs_function);
if (!f->descriptors)
goto fail;
rndis->fs.in = usb_find_endpoint(eth_fs_function,
f->descriptors, &fs_in_desc);
rndis->fs.out = usb_find_endpoint(eth_fs_function,
f->descriptors, &fs_out_desc);
rndis->fs.notify = usb_find_endpoint(eth_fs_function,
f->descriptors, &fs_notify_desc);
/* support all relevant hardware speeds... we expect that when
* hardware is dual speed, all bulk-capable endpoints work at
* both speeds
*/
if (gadget_is_dualspeed(c->cdev->gadget)) {
hs_in_desc.bEndpointAddress =
fs_in_desc.bEndpointAddress;
hs_out_desc.bEndpointAddress =
fs_out_desc.bEndpointAddress;
/* copy descriptors, and track endpoint copies */
f->hs_descriptors = usb_copy_descriptors(eth_hs_function);
if (!f->hs_descriptors)
goto fail;
rndis->hs.in = usb_find_endpoint(eth_hs_function,
f->hs_descriptors, &hs_in_desc);
rndis->hs.out = usb_find_endpoint(eth_hs_function,
f->hs_descriptors, &hs_out_desc);
}
rndis->port.open = rndis_open;
rndis->port.close = rndis_close;
status = rndis_register(rndis_response_available, rndis);
if (status < 0)
goto fail;
rndis->config = status;
rndis_set_param_medium(rndis->config, NDIS_MEDIUM_802_3, 0);
rndis_set_host_mac(rndis->config, rndis->ethaddr);
#if 0
// FIXME
if (rndis_set_param_vendor(rndis->config, vendorID,
manufacturer))
goto fail0;
#endif
/* NOTE: all that is done without knowing or caring about
* the network link ... which is unavailable to this code
* until we're activated via set_alt().
*/
DBG(cdev, "RNDIS: %s speed IN/%s OUT/%s NOTIFY/%s\n",
gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
rndis->port.in_ep->name, rndis->port.out_ep->name,
rndis->notify->name);
return 0;
fail:
if (gadget_is_dualspeed(c->cdev->gadget) && f->hs_descriptors)
usb_free_descriptors(f->hs_descriptors);
if (f->descriptors)
usb_free_descriptors(f->descriptors);
if (rndis->notify_req) {
kfree(rndis->notify_req->buf);
usb_ep_free_request(rndis->notify, rndis->notify_req);
}
/* we might as well release our claims on endpoints */
if (rndis->notify)
rndis->notify->driver_data = NULL;
if (rndis->port.out)
rndis->port.out_ep->driver_data = NULL;
if (rndis->port.in)
rndis->port.in_ep->driver_data = NULL;
ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
return status;
}
static void
rndis_unbind(struct usb_configuration *c, struct usb_function *f)
{
struct f_rndis *rndis = func_to_rndis(f);
rndis_deregister(rndis->config);
rndis_exit();
if (gadget_is_dualspeed(c->cdev->gadget))
usb_free_descriptors(f->hs_descriptors);
usb_free_descriptors(f->descriptors);
kfree(rndis->notify_req->buf);
usb_ep_free_request(rndis->notify, rndis->notify_req);
kfree(rndis);
}
/* Some controllers can't support RNDIS ... */
static inline bool can_support_rndis(struct usb_configuration *c)
{
/* only two endpoints on sa1100 */
if (gadget_is_sa1100(c->cdev->gadget))
return false;
/* everything else is *presumably* fine */
return true;
}
/**
* rndis_bind_config - add RNDIS network link to a configuration
* @c: the configuration to support the network link
* @ethaddr: a buffer in which the ethernet address of the host side
* side of the link was recorded
* Context: single threaded during gadget setup
*
* Returns zero on success, else negative errno.
*
* Caller must have called @gether_setup(). Caller is also responsible
* for calling @gether_cleanup() before module unload.
*/
int __init rndis_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN])
{
struct f_rndis *rndis;
int status;
if (!can_support_rndis(c) || !ethaddr)
return -EINVAL;
/* maybe allocate device-global string IDs */
if (rndis_string_defs[0].id == 0) {
/* ... and setup RNDIS itself */
status = rndis_init();
if (status < 0)
return status;
/* control interface label */
status = usb_string_id(c->cdev);
if (status < 0)
return status;
rndis_string_defs[0].id = status;
rndis_control_intf.iInterface = status;
/* data interface label */
status = usb_string_id(c->cdev);
if (status < 0)
return status;
rndis_string_defs[1].id = status;
rndis_data_intf.iInterface = status;
}
/* allocate and initialize one new instance */
status = -ENOMEM;
rndis = kzalloc(sizeof *rndis, GFP_KERNEL);
if (!rndis)
goto fail;
memcpy(rndis->ethaddr, ethaddr, ETH_ALEN);
/* RNDIS activates when the host changes this filter */
rndis->port.cdc_filter = 0;
/* RNDIS has special (and complex) framing */
rndis->port.header_len = sizeof(struct rndis_packet_msg_type);
rndis->port.wrap = rndis_add_header;
rndis->port.unwrap = rndis_rm_hdr;
rndis->port.func.name = "rndis";
rndis->port.func.strings = rndis_strings;
/* descriptors are per-instance copies */
rndis->port.func.bind = rndis_bind;
rndis->port.func.unbind = rndis_unbind;
rndis->port.func.set_alt = rndis_set_alt;
rndis->port.func.setup = rndis_setup;
rndis->port.func.disable = rndis_disable;
status = usb_add_function(c, &rndis->port.func);
if (status) {
kfree(rndis);
fail:
rndis_exit();
}
return status;
}
