Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 1 | /* |
| 2 | * f_eem.c -- USB CDC Ethernet (EEM) link function driver |
| 3 | * |
| 4 | * Copyright (C) 2003-2005,2008 David Brownell |
| 5 | * Copyright (C) 2008 Nokia Corporation |
| 6 | * Copyright (C) 2009 EF Johnson Technologies |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License as published by |
| 10 | * the Free Software Foundation; either version 2 of the License, or |
| 11 | * (at your option) any later version. |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 12 | */ |
| 13 | |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/device.h> |
| 16 | #include <linux/etherdevice.h> |
| 17 | #include <linux/crc32.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 18 | #include <linux/slab.h> |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 19 | |
| 20 | #include "u_ether.h" |
| 21 | |
| 22 | #define EEM_HLEN 2 |
| 23 | |
| 24 | /* |
| 25 | * This function is a "CDC Ethernet Emulation Model" (CDC EEM) |
| 26 | * Ethernet link. |
| 27 | */ |
| 28 | |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 29 | struct f_eem { |
| 30 | struct gether port; |
| 31 | u8 ctrl_id; |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 32 | }; |
| 33 | |
| 34 | static inline struct f_eem *func_to_eem(struct usb_function *f) |
| 35 | { |
| 36 | return container_of(f, struct f_eem, port.func); |
| 37 | } |
| 38 | |
| 39 | /*-------------------------------------------------------------------------*/ |
| 40 | |
| 41 | /* interface descriptor: */ |
| 42 | |
| 43 | static struct usb_interface_descriptor eem_intf __initdata = { |
| 44 | .bLength = sizeof eem_intf, |
| 45 | .bDescriptorType = USB_DT_INTERFACE, |
| 46 | |
| 47 | /* .bInterfaceNumber = DYNAMIC */ |
| 48 | .bNumEndpoints = 2, |
| 49 | .bInterfaceClass = USB_CLASS_COMM, |
| 50 | .bInterfaceSubClass = USB_CDC_SUBCLASS_EEM, |
| 51 | .bInterfaceProtocol = USB_CDC_PROTO_EEM, |
| 52 | /* .iInterface = DYNAMIC */ |
| 53 | }; |
| 54 | |
| 55 | /* full speed support: */ |
| 56 | |
| 57 | static struct usb_endpoint_descriptor eem_fs_in_desc __initdata = { |
| 58 | .bLength = USB_DT_ENDPOINT_SIZE, |
| 59 | .bDescriptorType = USB_DT_ENDPOINT, |
| 60 | |
| 61 | .bEndpointAddress = USB_DIR_IN, |
| 62 | .bmAttributes = USB_ENDPOINT_XFER_BULK, |
| 63 | }; |
| 64 | |
| 65 | static struct usb_endpoint_descriptor eem_fs_out_desc __initdata = { |
| 66 | .bLength = USB_DT_ENDPOINT_SIZE, |
| 67 | .bDescriptorType = USB_DT_ENDPOINT, |
| 68 | |
| 69 | .bEndpointAddress = USB_DIR_OUT, |
| 70 | .bmAttributes = USB_ENDPOINT_XFER_BULK, |
| 71 | }; |
| 72 | |
| 73 | static struct usb_descriptor_header *eem_fs_function[] __initdata = { |
| 74 | /* CDC EEM control descriptors */ |
| 75 | (struct usb_descriptor_header *) &eem_intf, |
| 76 | (struct usb_descriptor_header *) &eem_fs_in_desc, |
| 77 | (struct usb_descriptor_header *) &eem_fs_out_desc, |
| 78 | NULL, |
| 79 | }; |
| 80 | |
| 81 | /* high speed support: */ |
| 82 | |
| 83 | static struct usb_endpoint_descriptor eem_hs_in_desc __initdata = { |
| 84 | .bLength = USB_DT_ENDPOINT_SIZE, |
| 85 | .bDescriptorType = USB_DT_ENDPOINT, |
| 86 | |
| 87 | .bEndpointAddress = USB_DIR_IN, |
| 88 | .bmAttributes = USB_ENDPOINT_XFER_BULK, |
| 89 | .wMaxPacketSize = cpu_to_le16(512), |
| 90 | }; |
| 91 | |
| 92 | static struct usb_endpoint_descriptor eem_hs_out_desc __initdata = { |
| 93 | .bLength = USB_DT_ENDPOINT_SIZE, |
| 94 | .bDescriptorType = USB_DT_ENDPOINT, |
| 95 | |
| 96 | .bEndpointAddress = USB_DIR_OUT, |
| 97 | .bmAttributes = USB_ENDPOINT_XFER_BULK, |
| 98 | .wMaxPacketSize = cpu_to_le16(512), |
| 99 | }; |
| 100 | |
| 101 | static struct usb_descriptor_header *eem_hs_function[] __initdata = { |
| 102 | /* CDC EEM control descriptors */ |
| 103 | (struct usb_descriptor_header *) &eem_intf, |
| 104 | (struct usb_descriptor_header *) &eem_hs_in_desc, |
| 105 | (struct usb_descriptor_header *) &eem_hs_out_desc, |
| 106 | NULL, |
| 107 | }; |
| 108 | |
Paul Zimmerman | 04617db | 2011-06-27 14:13:18 -0700 | [diff] [blame] | 109 | /* super speed support: */ |
| 110 | |
| 111 | static struct usb_endpoint_descriptor eem_ss_in_desc __initdata = { |
| 112 | .bLength = USB_DT_ENDPOINT_SIZE, |
| 113 | .bDescriptorType = USB_DT_ENDPOINT, |
| 114 | |
| 115 | .bEndpointAddress = USB_DIR_IN, |
| 116 | .bmAttributes = USB_ENDPOINT_XFER_BULK, |
| 117 | .wMaxPacketSize = cpu_to_le16(1024), |
| 118 | }; |
| 119 | |
| 120 | static struct usb_endpoint_descriptor eem_ss_out_desc __initdata = { |
| 121 | .bLength = USB_DT_ENDPOINT_SIZE, |
| 122 | .bDescriptorType = USB_DT_ENDPOINT, |
| 123 | |
| 124 | .bEndpointAddress = USB_DIR_OUT, |
| 125 | .bmAttributes = USB_ENDPOINT_XFER_BULK, |
| 126 | .wMaxPacketSize = cpu_to_le16(1024), |
| 127 | }; |
| 128 | |
| 129 | static struct usb_ss_ep_comp_descriptor eem_ss_bulk_comp_desc __initdata = { |
| 130 | .bLength = sizeof eem_ss_bulk_comp_desc, |
| 131 | .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, |
| 132 | |
| 133 | /* the following 2 values can be tweaked if necessary */ |
| 134 | /* .bMaxBurst = 0, */ |
| 135 | /* .bmAttributes = 0, */ |
| 136 | }; |
| 137 | |
| 138 | static struct usb_descriptor_header *eem_ss_function[] __initdata = { |
| 139 | /* CDC EEM control descriptors */ |
| 140 | (struct usb_descriptor_header *) &eem_intf, |
| 141 | (struct usb_descriptor_header *) &eem_ss_in_desc, |
| 142 | (struct usb_descriptor_header *) &eem_ss_bulk_comp_desc, |
| 143 | (struct usb_descriptor_header *) &eem_ss_out_desc, |
| 144 | (struct usb_descriptor_header *) &eem_ss_bulk_comp_desc, |
| 145 | NULL, |
| 146 | }; |
| 147 | |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 148 | /* string descriptors: */ |
| 149 | |
| 150 | static struct usb_string eem_string_defs[] = { |
| 151 | [0].s = "CDC Ethernet Emulation Model (EEM)", |
| 152 | { } /* end of list */ |
| 153 | }; |
| 154 | |
| 155 | static struct usb_gadget_strings eem_string_table = { |
| 156 | .language = 0x0409, /* en-us */ |
| 157 | .strings = eem_string_defs, |
| 158 | }; |
| 159 | |
| 160 | static struct usb_gadget_strings *eem_strings[] = { |
| 161 | &eem_string_table, |
| 162 | NULL, |
| 163 | }; |
| 164 | |
| 165 | /*-------------------------------------------------------------------------*/ |
| 166 | |
| 167 | static int eem_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl) |
| 168 | { |
| 169 | struct usb_composite_dev *cdev = f->config->cdev; |
| 170 | int value = -EOPNOTSUPP; |
| 171 | u16 w_index = le16_to_cpu(ctrl->wIndex); |
| 172 | u16 w_value = le16_to_cpu(ctrl->wValue); |
| 173 | u16 w_length = le16_to_cpu(ctrl->wLength); |
| 174 | |
| 175 | DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n", |
| 176 | ctrl->bRequestType, ctrl->bRequest, |
| 177 | w_value, w_index, w_length); |
| 178 | |
| 179 | /* device either stalls (value < 0) or reports success */ |
| 180 | return value; |
| 181 | } |
| 182 | |
| 183 | |
| 184 | static int eem_set_alt(struct usb_function *f, unsigned intf, unsigned alt) |
| 185 | { |
| 186 | struct f_eem *eem = func_to_eem(f); |
| 187 | struct usb_composite_dev *cdev = f->config->cdev; |
| 188 | struct net_device *net; |
| 189 | |
| 190 | /* we know alt == 0, so this is an activation or a reset */ |
| 191 | if (alt != 0) |
| 192 | goto fail; |
| 193 | |
| 194 | if (intf == eem->ctrl_id) { |
| 195 | |
| 196 | if (eem->port.in_ep->driver_data) { |
| 197 | DBG(cdev, "reset eem\n"); |
| 198 | gether_disconnect(&eem->port); |
| 199 | } |
| 200 | |
Tatyana Brokhman | ea2a1df | 2011-06-28 16:33:50 +0300 | [diff] [blame] | 201 | if (!eem->port.in_ep->desc || !eem->port.out_ep->desc) { |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 202 | DBG(cdev, "init eem\n"); |
Tatyana Brokhman | ea2a1df | 2011-06-28 16:33:50 +0300 | [diff] [blame] | 203 | if (config_ep_by_speed(cdev->gadget, f, |
| 204 | eem->port.in_ep) || |
| 205 | config_ep_by_speed(cdev->gadget, f, |
| 206 | eem->port.out_ep)) { |
| 207 | eem->port.in_ep->desc = NULL; |
| 208 | eem->port.out_ep->desc = NULL; |
| 209 | goto fail; |
| 210 | } |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 211 | } |
| 212 | |
| 213 | /* zlps should not occur because zero-length EEM packets |
| 214 | * will be inserted in those cases where they would occur |
| 215 | */ |
| 216 | eem->port.is_zlp_ok = 1; |
| 217 | eem->port.cdc_filter = DEFAULT_FILTER; |
| 218 | DBG(cdev, "activate eem\n"); |
| 219 | net = gether_connect(&eem->port); |
| 220 | if (IS_ERR(net)) |
| 221 | return PTR_ERR(net); |
| 222 | } else |
| 223 | goto fail; |
| 224 | |
| 225 | return 0; |
| 226 | fail: |
| 227 | return -EINVAL; |
| 228 | } |
| 229 | |
| 230 | static void eem_disable(struct usb_function *f) |
| 231 | { |
| 232 | struct f_eem *eem = func_to_eem(f); |
| 233 | struct usb_composite_dev *cdev = f->config->cdev; |
| 234 | |
| 235 | DBG(cdev, "eem deactivated\n"); |
| 236 | |
| 237 | if (eem->port.in_ep->driver_data) |
| 238 | gether_disconnect(&eem->port); |
| 239 | } |
| 240 | |
| 241 | /*-------------------------------------------------------------------------*/ |
| 242 | |
| 243 | /* EEM function driver setup/binding */ |
| 244 | |
| 245 | static int __init |
| 246 | eem_bind(struct usb_configuration *c, struct usb_function *f) |
| 247 | { |
| 248 | struct usb_composite_dev *cdev = c->cdev; |
| 249 | struct f_eem *eem = func_to_eem(f); |
| 250 | int status; |
| 251 | struct usb_ep *ep; |
| 252 | |
| 253 | /* allocate instance-specific interface IDs */ |
| 254 | status = usb_interface_id(c, f); |
| 255 | if (status < 0) |
| 256 | goto fail; |
| 257 | eem->ctrl_id = status; |
| 258 | eem_intf.bInterfaceNumber = status; |
| 259 | |
| 260 | status = -ENODEV; |
| 261 | |
| 262 | /* allocate instance-specific endpoints */ |
| 263 | ep = usb_ep_autoconfig(cdev->gadget, &eem_fs_in_desc); |
| 264 | if (!ep) |
| 265 | goto fail; |
| 266 | eem->port.in_ep = ep; |
| 267 | ep->driver_data = cdev; /* claim */ |
| 268 | |
| 269 | ep = usb_ep_autoconfig(cdev->gadget, &eem_fs_out_desc); |
| 270 | if (!ep) |
| 271 | goto fail; |
| 272 | eem->port.out_ep = ep; |
| 273 | ep->driver_data = cdev; /* claim */ |
| 274 | |
| 275 | status = -ENOMEM; |
| 276 | |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 277 | /* support all relevant hardware speeds... we expect that when |
| 278 | * hardware is dual speed, all bulk-capable endpoints work at |
| 279 | * both speeds |
| 280 | */ |
Sebastian Andrzej Siewior | 10287ba | 2012-10-22 22:15:06 +0200 | [diff] [blame] | 281 | eem_hs_in_desc.bEndpointAddress = eem_fs_in_desc.bEndpointAddress; |
| 282 | eem_hs_out_desc.bEndpointAddress = eem_fs_out_desc.bEndpointAddress; |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 283 | |
Sebastian Andrzej Siewior | 10287ba | 2012-10-22 22:15:06 +0200 | [diff] [blame] | 284 | eem_ss_in_desc.bEndpointAddress = eem_fs_in_desc.bEndpointAddress; |
| 285 | eem_ss_out_desc.bEndpointAddress = eem_fs_out_desc.bEndpointAddress; |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 286 | |
Sebastian Andrzej Siewior | 10287ba | 2012-10-22 22:15:06 +0200 | [diff] [blame] | 287 | status = usb_assign_descriptors(f, eem_fs_function, eem_hs_function, |
| 288 | eem_ss_function); |
| 289 | if (status) |
| 290 | goto fail; |
Paul Zimmerman | 04617db | 2011-06-27 14:13:18 -0700 | [diff] [blame] | 291 | |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 292 | DBG(cdev, "CDC Ethernet (EEM): %s speed IN/%s OUT/%s\n", |
Paul Zimmerman | 04617db | 2011-06-27 14:13:18 -0700 | [diff] [blame] | 293 | gadget_is_superspeed(c->cdev->gadget) ? "super" : |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 294 | gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full", |
| 295 | eem->port.in_ep->name, eem->port.out_ep->name); |
| 296 | return 0; |
| 297 | |
| 298 | fail: |
Sebastian Andrzej Siewior | 10287ba | 2012-10-22 22:15:06 +0200 | [diff] [blame] | 299 | usb_free_all_descriptors(f); |
Sebastian Andrzej Siewior | e79cc61 | 2012-10-22 22:15:00 +0200 | [diff] [blame] | 300 | if (eem->port.out_ep) |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 301 | eem->port.out_ep->driver_data = NULL; |
Sebastian Andrzej Siewior | e79cc61 | 2012-10-22 22:15:00 +0200 | [diff] [blame] | 302 | if (eem->port.in_ep) |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 303 | eem->port.in_ep->driver_data = NULL; |
| 304 | |
| 305 | ERROR(cdev, "%s: can't bind, err %d\n", f->name, status); |
| 306 | |
| 307 | return status; |
| 308 | } |
| 309 | |
| 310 | static void |
| 311 | eem_unbind(struct usb_configuration *c, struct usb_function *f) |
| 312 | { |
| 313 | struct f_eem *eem = func_to_eem(f); |
| 314 | |
| 315 | DBG(c->cdev, "eem unbind\n"); |
| 316 | |
Sebastian Andrzej Siewior | 10287ba | 2012-10-22 22:15:06 +0200 | [diff] [blame] | 317 | usb_free_all_descriptors(f); |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 318 | kfree(eem); |
| 319 | } |
| 320 | |
| 321 | static void eem_cmd_complete(struct usb_ep *ep, struct usb_request *req) |
| 322 | { |
Yauheni Kaliuta | 505d1f6 | 2011-04-05 16:55:25 +0300 | [diff] [blame] | 323 | struct sk_buff *skb = (struct sk_buff *)req->context; |
| 324 | |
| 325 | dev_kfree_skb_any(skb); |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 326 | } |
| 327 | |
| 328 | /* |
| 329 | * Add the EEM header and ethernet checksum. |
| 330 | * We currently do not attempt to put multiple ethernet frames |
| 331 | * into a single USB transfer |
| 332 | */ |
| 333 | static struct sk_buff *eem_wrap(struct gether *port, struct sk_buff *skb) |
| 334 | { |
| 335 | struct sk_buff *skb2 = NULL; |
| 336 | struct usb_ep *in = port->in_ep; |
| 337 | int padlen = 0; |
| 338 | u16 len = skb->len; |
| 339 | |
| 340 | if (!skb_cloned(skb)) { |
| 341 | int headroom = skb_headroom(skb); |
| 342 | int tailroom = skb_tailroom(skb); |
| 343 | |
| 344 | /* When (len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) is 0, |
| 345 | * stick two bytes of zero-length EEM packet on the end. |
| 346 | */ |
| 347 | if (((len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) == 0) |
| 348 | padlen += 2; |
| 349 | |
| 350 | if ((tailroom >= (ETH_FCS_LEN + padlen)) && |
| 351 | (headroom >= EEM_HLEN)) |
| 352 | goto done; |
| 353 | } |
| 354 | |
| 355 | skb2 = skb_copy_expand(skb, EEM_HLEN, ETH_FCS_LEN + padlen, GFP_ATOMIC); |
| 356 | dev_kfree_skb_any(skb); |
| 357 | skb = skb2; |
| 358 | if (!skb) |
| 359 | return skb; |
| 360 | |
| 361 | done: |
| 362 | /* use the "no CRC" option */ |
| 363 | put_unaligned_be32(0xdeadbeef, skb_put(skb, 4)); |
| 364 | |
| 365 | /* EEM packet header format: |
| 366 | * b0..13: length of ethernet frame |
| 367 | * b14: bmCRC (0 == sentinel CRC) |
| 368 | * b15: bmType (0 == data) |
| 369 | */ |
| 370 | len = skb->len; |
Brian Niebuhr | 31e5d4a | 2010-01-25 14:45:40 -0600 | [diff] [blame] | 371 | put_unaligned_le16(len & 0x3FFF, skb_push(skb, 2)); |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 372 | |
| 373 | /* add a zero-length EEM packet, if needed */ |
| 374 | if (padlen) |
| 375 | put_unaligned_le16(0, skb_put(skb, 2)); |
| 376 | |
| 377 | return skb; |
| 378 | } |
| 379 | |
| 380 | /* |
| 381 | * Remove the EEM header. Note that there can be many EEM packets in a single |
| 382 | * USB transfer, so we need to break them out and handle them independently. |
| 383 | */ |
| 384 | static int eem_unwrap(struct gether *port, |
| 385 | struct sk_buff *skb, |
| 386 | struct sk_buff_head *list) |
| 387 | { |
| 388 | struct usb_composite_dev *cdev = port->func.config->cdev; |
| 389 | int status = 0; |
| 390 | |
| 391 | do { |
| 392 | struct sk_buff *skb2; |
| 393 | u16 header; |
| 394 | u16 len = 0; |
| 395 | |
| 396 | if (skb->len < EEM_HLEN) { |
| 397 | status = -EINVAL; |
| 398 | DBG(cdev, "invalid EEM header\n"); |
| 399 | goto error; |
| 400 | } |
| 401 | |
| 402 | /* remove the EEM header */ |
| 403 | header = get_unaligned_le16(skb->data); |
| 404 | skb_pull(skb, EEM_HLEN); |
| 405 | |
| 406 | /* EEM packet header format: |
| 407 | * b0..14: EEM type dependent (data or command) |
| 408 | * b15: bmType (0 == data, 1 == command) |
| 409 | */ |
| 410 | if (header & BIT(15)) { |
| 411 | struct usb_request *req = cdev->req; |
| 412 | u16 bmEEMCmd; |
| 413 | |
| 414 | /* EEM command packet format: |
| 415 | * b0..10: bmEEMCmdParam |
| 416 | * b11..13: bmEEMCmd |
| 417 | * b14: reserved (must be zero) |
| 418 | * b15: bmType (1 == command) |
| 419 | */ |
| 420 | if (header & BIT(14)) |
| 421 | continue; |
| 422 | |
| 423 | bmEEMCmd = (header >> 11) & 0x7; |
| 424 | switch (bmEEMCmd) { |
| 425 | case 0: /* echo */ |
| 426 | len = header & 0x7FF; |
| 427 | if (skb->len < len) { |
| 428 | status = -EOVERFLOW; |
| 429 | goto error; |
| 430 | } |
| 431 | |
| 432 | skb2 = skb_clone(skb, GFP_ATOMIC); |
| 433 | if (unlikely(!skb2)) { |
| 434 | DBG(cdev, "EEM echo response error\n"); |
| 435 | goto next; |
| 436 | } |
| 437 | skb_trim(skb2, len); |
| 438 | put_unaligned_le16(BIT(15) | BIT(11) | len, |
| 439 | skb_push(skb2, 2)); |
Yauheni Kaliuta | 505d1f6 | 2011-04-05 16:55:25 +0300 | [diff] [blame] | 440 | skb_copy_bits(skb2, 0, req->buf, skb2->len); |
| 441 | req->length = skb2->len; |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 442 | req->complete = eem_cmd_complete; |
| 443 | req->zero = 1; |
Yauheni Kaliuta | 505d1f6 | 2011-04-05 16:55:25 +0300 | [diff] [blame] | 444 | req->context = skb2; |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 445 | if (usb_ep_queue(port->in_ep, req, GFP_ATOMIC)) |
| 446 | DBG(cdev, "echo response queue fail\n"); |
| 447 | break; |
| 448 | |
| 449 | case 1: /* echo response */ |
| 450 | case 2: /* suspend hint */ |
| 451 | case 3: /* response hint */ |
| 452 | case 4: /* response complete hint */ |
| 453 | case 5: /* tickle */ |
| 454 | default: /* reserved */ |
| 455 | continue; |
| 456 | } |
| 457 | } else { |
| 458 | u32 crc, crc2; |
| 459 | struct sk_buff *skb3; |
| 460 | |
| 461 | /* check for zero-length EEM packet */ |
| 462 | if (header == 0) |
| 463 | continue; |
| 464 | |
| 465 | /* EEM data packet format: |
| 466 | * b0..13: length of ethernet frame |
| 467 | * b14: bmCRC (0 == sentinel, 1 == calculated) |
| 468 | * b15: bmType (0 == data) |
| 469 | */ |
| 470 | len = header & 0x3FFF; |
| 471 | if ((skb->len < len) |
| 472 | || (len < (ETH_HLEN + ETH_FCS_LEN))) { |
| 473 | status = -EINVAL; |
| 474 | goto error; |
| 475 | } |
| 476 | |
| 477 | /* validate CRC */ |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 478 | if (header & BIT(14)) { |
| 479 | crc = get_unaligned_le32(skb->data + len |
| 480 | - ETH_FCS_LEN); |
| 481 | crc2 = ~crc32_le(~0, |
Jiri Pinkava | 03ab746 | 2010-06-20 20:05:52 +0200 | [diff] [blame] | 482 | skb->data, len - ETH_FCS_LEN); |
Brian Niebuhr | 9b39e9d | 2009-08-14 10:04:22 -0500 | [diff] [blame] | 483 | } else { |
| 484 | crc = get_unaligned_be32(skb->data + len |
| 485 | - ETH_FCS_LEN); |
| 486 | crc2 = 0xdeadbeef; |
| 487 | } |
| 488 | if (crc != crc2) { |
| 489 | DBG(cdev, "invalid EEM CRC\n"); |
| 490 | goto next; |
| 491 | } |
| 492 | |
| 493 | skb2 = skb_clone(skb, GFP_ATOMIC); |
| 494 | if (unlikely(!skb2)) { |
| 495 | DBG(cdev, "unable to unframe EEM packet\n"); |
| 496 | continue; |
| 497 | } |
| 498 | skb_trim(skb2, len - ETH_FCS_LEN); |
| 499 | |
| 500 | skb3 = skb_copy_expand(skb2, |
| 501 | NET_IP_ALIGN, |
| 502 | 0, |
| 503 | GFP_ATOMIC); |
| 504 | if (unlikely(!skb3)) { |
| 505 | DBG(cdev, "unable to realign EEM packet\n"); |
| 506 | dev_kfree_skb_any(skb2); |
| 507 | continue; |
| 508 | } |
| 509 | dev_kfree_skb_any(skb2); |
| 510 | skb_queue_tail(list, skb3); |
| 511 | } |
| 512 | next: |
| 513 | skb_pull(skb, len); |
| 514 | } while (skb->len); |
| 515 | |
| 516 | error: |
| 517 | dev_kfree_skb_any(skb); |
| 518 | return status; |
| 519 | } |
| 520 | |
| 521 | /** |
| 522 | * eem_bind_config - add CDC Ethernet (EEM) network link to a configuration |
| 523 | * @c: the configuration to support the network link |
| 524 | * Context: single threaded during gadget setup |
| 525 | * |
| 526 | * Returns zero on success, else negative errno. |
| 527 | * |
| 528 | * Caller must have called @gether_setup(). Caller is also responsible |
| 529 | * for calling @gether_cleanup() before module unload. |
| 530 | */ |
| 531 | int __init eem_bind_config(struct usb_configuration *c) |
| 532 | { |
| 533 | struct f_eem *eem; |
| 534 | int status; |
| 535 | |
| 536 | /* maybe allocate device-global string IDs */ |
| 537 | if (eem_string_defs[0].id == 0) { |
| 538 | |
| 539 | /* control interface label */ |
| 540 | status = usb_string_id(c->cdev); |
| 541 | if (status < 0) |
| 542 | return status; |
| 543 | eem_string_defs[0].id = status; |
| 544 | eem_intf.iInterface = status; |
| 545 | } |
| 546 | |
| 547 | /* allocate and initialize one new instance */ |
| 548 | eem = kzalloc(sizeof *eem, GFP_KERNEL); |
| 549 | if (!eem) |
| 550 | return -ENOMEM; |
| 551 | |
| 552 | eem->port.cdc_filter = DEFAULT_FILTER; |
| 553 | |
| 554 | eem->port.func.name = "cdc_eem"; |
| 555 | eem->port.func.strings = eem_strings; |
| 556 | /* descriptors are per-instance copies */ |
| 557 | eem->port.func.bind = eem_bind; |
| 558 | eem->port.func.unbind = eem_unbind; |
| 559 | eem->port.func.set_alt = eem_set_alt; |
| 560 | eem->port.func.setup = eem_setup; |
| 561 | eem->port.func.disable = eem_disable; |
| 562 | eem->port.wrap = eem_wrap; |
| 563 | eem->port.unwrap = eem_unwrap; |
| 564 | eem->port.header_len = EEM_HLEN; |
| 565 | |
| 566 | status = usb_add_function(c, &eem->port.func); |
| 567 | if (status) |
| 568 | kfree(eem); |
| 569 | return status; |
| 570 | } |
| 571 | |