diff options
Diffstat (limited to 'drivers/usb/gadget/f_rndis.c')
| -rw-r--r-- | drivers/usb/gadget/f_rndis.c | 825 |
1 files changed, 825 insertions, 0 deletions
diff --git a/drivers/usb/gadget/f_rndis.c b/drivers/usb/gadget/f_rndis.c new file mode 100644 index 00000000000..659b3d9671c --- /dev/null +++ b/drivers/usb/gadget/f_rndis.c @@ -0,0 +1,825 @@ +/* + * 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 */ + .bAlternateSetting = 1, + .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)) + 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; +} |