1 /* 2 * phonet.c -- USB CDC Phonet host driver 3 * 4 * Copyright (C) 2008-2009 Nokia Corporation. All rights reserved. 5 * 6 * Author: Rémi Denis-Courmont 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * version 2 as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, but 13 * WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 20 * 02110-1301 USA 21 */ 22 23 #include <linux/kernel.h> 24 #include <linux/mm.h> 25 #include <linux/module.h> 26 #include <linux/gfp.h> 27 #include <linux/usb.h> 28 #include <linux/usb/cdc.h> 29 #include <linux/netdevice.h> 30 #include <linux/if_arp.h> 31 #include <linux/if_phonet.h> 32 #include <linux/phonet.h> 33 34 #define PN_MEDIA_USB 0x1B 35 36 static const unsigned rxq_size = 17; 37 38 struct usbpn_dev { 39 struct net_device *dev; 40 41 struct usb_interface *intf, *data_intf; 42 struct usb_device *usb; 43 unsigned int tx_pipe, rx_pipe; 44 u8 active_setting; 45 u8 disconnected; 46 47 unsigned tx_queue; 48 spinlock_t tx_lock; 49 50 spinlock_t rx_lock; 51 struct sk_buff *rx_skb; 52 struct urb *urbs[0]; 53 }; 54 55 static void tx_complete(struct urb *req); 56 static void rx_complete(struct urb *req); 57 58 /* 59 * Network device callbacks 60 */ 61 static netdev_tx_t usbpn_xmit(struct sk_buff *skb, struct net_device *dev) 62 { 63 struct usbpn_dev *pnd = netdev_priv(dev); 64 struct urb *req = NULL; 65 unsigned long flags; 66 int err; 67 68 if (skb->protocol != htons(ETH_P_PHONET)) 69 goto drop; 70 71 req = usb_alloc_urb(0, GFP_ATOMIC); 72 if (!req) 73 goto drop; 74 usb_fill_bulk_urb(req, pnd->usb, pnd->tx_pipe, skb->data, skb->len, 75 tx_complete, skb); 76 req->transfer_flags = URB_ZERO_PACKET; 77 err = usb_submit_urb(req, GFP_ATOMIC); 78 if (err) { 79 usb_free_urb(req); 80 goto drop; 81 } 82 83 spin_lock_irqsave(&pnd->tx_lock, flags); 84 pnd->tx_queue++; 85 if (pnd->tx_queue >= dev->tx_queue_len) 86 netif_stop_queue(dev); 87 spin_unlock_irqrestore(&pnd->tx_lock, flags); 88 return NETDEV_TX_OK; 89 90 drop: 91 dev_kfree_skb(skb); 92 dev->stats.tx_dropped++; 93 return NETDEV_TX_OK; 94 } 95 96 static void tx_complete(struct urb *req) 97 { 98 struct sk_buff *skb = req->context; 99 struct net_device *dev = skb->dev; 100 struct usbpn_dev *pnd = netdev_priv(dev); 101 int status = req->status; 102 103 switch (status) { 104 case 0: 105 dev->stats.tx_bytes += skb->len; 106 break; 107 108 case -ENOENT: 109 case -ECONNRESET: 110 case -ESHUTDOWN: 111 dev->stats.tx_aborted_errors++; 112 default: 113 dev->stats.tx_errors++; 114 dev_dbg(&dev->dev, "TX error (%d)\n", status); 115 } 116 dev->stats.tx_packets++; 117 118 spin_lock(&pnd->tx_lock); 119 pnd->tx_queue--; 120 netif_wake_queue(dev); 121 spin_unlock(&pnd->tx_lock); 122 123 dev_kfree_skb_any(skb); 124 usb_free_urb(req); 125 } 126 127 static int rx_submit(struct usbpn_dev *pnd, struct urb *req, gfp_t gfp_flags) 128 { 129 struct net_device *dev = pnd->dev; 130 struct page *page; 131 int err; 132 133 page = __netdev_alloc_page(dev, gfp_flags); 134 if (!page) 135 return -ENOMEM; 136 137 usb_fill_bulk_urb(req, pnd->usb, pnd->rx_pipe, page_address(page), 138 PAGE_SIZE, rx_complete, dev); 139 req->transfer_flags = 0; 140 err = usb_submit_urb(req, gfp_flags); 141 if (unlikely(err)) { 142 dev_dbg(&dev->dev, "RX submit error (%d)\n", err); 143 netdev_free_page(dev, page); 144 } 145 return err; 146 } 147 148 static void rx_complete(struct urb *req) 149 { 150 struct net_device *dev = req->context; 151 struct usbpn_dev *pnd = netdev_priv(dev); 152 struct page *page = virt_to_page(req->transfer_buffer); 153 struct sk_buff *skb; 154 unsigned long flags; 155 int status = req->status; 156 157 switch (status) { 158 case 0: 159 spin_lock_irqsave(&pnd->rx_lock, flags); 160 skb = pnd->rx_skb; 161 if (!skb) { 162 skb = pnd->rx_skb = netdev_alloc_skb(dev, 12); 163 if (likely(skb)) { 164 /* Can't use pskb_pull() on page in IRQ */ 165 memcpy(skb_put(skb, 1), page_address(page), 1); 166 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, 167 page, 1, req->actual_length); 168 page = NULL; 169 } 170 } else { 171 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, 172 page, 0, req->actual_length); 173 page = NULL; 174 } 175 if (req->actual_length < PAGE_SIZE) 176 pnd->rx_skb = NULL; /* Last fragment */ 177 else 178 skb = NULL; 179 spin_unlock_irqrestore(&pnd->rx_lock, flags); 180 if (skb) { 181 skb->protocol = htons(ETH_P_PHONET); 182 skb_reset_mac_header(skb); 183 __skb_pull(skb, 1); 184 skb->dev = dev; 185 dev->stats.rx_packets++; 186 dev->stats.rx_bytes += skb->len; 187 188 netif_rx(skb); 189 } 190 goto resubmit; 191 192 case -ENOENT: 193 case -ECONNRESET: 194 case -ESHUTDOWN: 195 req = NULL; 196 break; 197 198 case -EOVERFLOW: 199 dev->stats.rx_over_errors++; 200 dev_dbg(&dev->dev, "RX overflow\n"); 201 break; 202 203 case -EILSEQ: 204 dev->stats.rx_crc_errors++; 205 break; 206 } 207 208 dev->stats.rx_errors++; 209 resubmit: 210 if (page) 211 netdev_free_page(dev, page); 212 if (req) 213 rx_submit(pnd, req, GFP_ATOMIC); 214 } 215 216 static int usbpn_close(struct net_device *dev); 217 218 static int usbpn_open(struct net_device *dev) 219 { 220 struct usbpn_dev *pnd = netdev_priv(dev); 221 int err; 222 unsigned i; 223 unsigned num = pnd->data_intf->cur_altsetting->desc.bInterfaceNumber; 224 225 err = usb_set_interface(pnd->usb, num, pnd->active_setting); 226 if (err) 227 return err; 228 229 for (i = 0; i < rxq_size; i++) { 230 struct urb *req = usb_alloc_urb(0, GFP_KERNEL); 231 232 if (!req || rx_submit(pnd, req, GFP_KERNEL)) { 233 usbpn_close(dev); 234 return -ENOMEM; 235 } 236 pnd->urbs[i] = req; 237 } 238 239 netif_wake_queue(dev); 240 return 0; 241 } 242 243 static int usbpn_close(struct net_device *dev) 244 { 245 struct usbpn_dev *pnd = netdev_priv(dev); 246 unsigned i; 247 unsigned num = pnd->data_intf->cur_altsetting->desc.bInterfaceNumber; 248 249 netif_stop_queue(dev); 250 251 for (i = 0; i < rxq_size; i++) { 252 struct urb *req = pnd->urbs[i]; 253 254 if (!req) 255 continue; 256 usb_kill_urb(req); 257 usb_free_urb(req); 258 pnd->urbs[i] = NULL; 259 } 260 261 return usb_set_interface(pnd->usb, num, !pnd->active_setting); 262 } 263 264 static int usbpn_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 265 { 266 struct if_phonet_req *req = (struct if_phonet_req *)ifr; 267 268 switch (cmd) { 269 case SIOCPNGAUTOCONF: 270 req->ifr_phonet_autoconf.device = PN_DEV_PC; 271 return 0; 272 } 273 return -ENOIOCTLCMD; 274 } 275 276 static int usbpn_set_mtu(struct net_device *dev, int new_mtu) 277 { 278 if ((new_mtu < PHONET_MIN_MTU) || (new_mtu > PHONET_MAX_MTU)) 279 return -EINVAL; 280 281 dev->mtu = new_mtu; 282 return 0; 283 } 284 285 static const struct net_device_ops usbpn_ops = { 286 .ndo_open = usbpn_open, 287 .ndo_stop = usbpn_close, 288 .ndo_start_xmit = usbpn_xmit, 289 .ndo_do_ioctl = usbpn_ioctl, 290 .ndo_change_mtu = usbpn_set_mtu, 291 }; 292 293 static void usbpn_setup(struct net_device *dev) 294 { 295 dev->features = 0; 296 dev->netdev_ops = &usbpn_ops, 297 dev->header_ops = &phonet_header_ops; 298 dev->type = ARPHRD_PHONET; 299 dev->flags = IFF_POINTOPOINT | IFF_NOARP; 300 dev->mtu = PHONET_MAX_MTU; 301 dev->hard_header_len = 1; 302 dev->dev_addr[0] = PN_MEDIA_USB; 303 dev->addr_len = 1; 304 dev->tx_queue_len = 3; 305 306 dev->destructor = free_netdev; 307 } 308 309 /* 310 * USB driver callbacks 311 */ 312 static struct usb_device_id usbpn_ids[] = { 313 { 314 .match_flags = USB_DEVICE_ID_MATCH_VENDOR 315 | USB_DEVICE_ID_MATCH_INT_CLASS 316 | USB_DEVICE_ID_MATCH_INT_SUBCLASS, 317 .idVendor = 0x0421, /* Nokia */ 318 .bInterfaceClass = USB_CLASS_COMM, 319 .bInterfaceSubClass = 0xFE, 320 }, 321 { }, 322 }; 323 324 MODULE_DEVICE_TABLE(usb, usbpn_ids); 325 326 static struct usb_driver usbpn_driver; 327 328 int usbpn_probe(struct usb_interface *intf, const struct usb_device_id *id) 329 { 330 static const char ifname[] = "usbpn%d"; 331 const struct usb_cdc_union_desc *union_header = NULL; 332 const struct usb_host_interface *data_desc; 333 struct usb_interface *data_intf; 334 struct usb_device *usbdev = interface_to_usbdev(intf); 335 struct net_device *dev; 336 struct usbpn_dev *pnd; 337 u8 *data; 338 int phonet = 0; 339 int len, err; 340 341 data = intf->altsetting->extra; 342 len = intf->altsetting->extralen; 343 while (len >= 3) { 344 u8 dlen = data[0]; 345 if (dlen < 3) 346 return -EINVAL; 347 348 /* bDescriptorType */ 349 if (data[1] == USB_DT_CS_INTERFACE) { 350 /* bDescriptorSubType */ 351 switch (data[2]) { 352 case USB_CDC_UNION_TYPE: 353 if (union_header || dlen < 5) 354 break; 355 union_header = 356 (struct usb_cdc_union_desc *)data; 357 break; 358 case 0xAB: 359 phonet = 1; 360 break; 361 } 362 } 363 data += dlen; 364 len -= dlen; 365 } 366 367 if (!union_header || !phonet) 368 return -EINVAL; 369 370 data_intf = usb_ifnum_to_if(usbdev, union_header->bSlaveInterface0); 371 if (data_intf == NULL) 372 return -ENODEV; 373 /* Data interface has one inactive and one active setting */ 374 if (data_intf->num_altsetting != 2) 375 return -EINVAL; 376 if (data_intf->altsetting[0].desc.bNumEndpoints == 0 && 377 data_intf->altsetting[1].desc.bNumEndpoints == 2) 378 data_desc = data_intf->altsetting + 1; 379 else 380 if (data_intf->altsetting[0].desc.bNumEndpoints == 2 && 381 data_intf->altsetting[1].desc.bNumEndpoints == 0) 382 data_desc = data_intf->altsetting; 383 else 384 return -EINVAL; 385 386 dev = alloc_netdev(sizeof(*pnd) + sizeof(pnd->urbs[0]) * rxq_size, 387 ifname, usbpn_setup); 388 if (!dev) 389 return -ENOMEM; 390 391 pnd = netdev_priv(dev); 392 SET_NETDEV_DEV(dev, &intf->dev); 393 394 pnd->dev = dev; 395 pnd->usb = usb_get_dev(usbdev); 396 pnd->intf = intf; 397 pnd->data_intf = data_intf; 398 spin_lock_init(&pnd->tx_lock); 399 spin_lock_init(&pnd->rx_lock); 400 /* Endpoints */ 401 if (usb_pipein(data_desc->endpoint[0].desc.bEndpointAddress)) { 402 pnd->rx_pipe = usb_rcvbulkpipe(usbdev, 403 data_desc->endpoint[0].desc.bEndpointAddress); 404 pnd->tx_pipe = usb_sndbulkpipe(usbdev, 405 data_desc->endpoint[1].desc.bEndpointAddress); 406 } else { 407 pnd->rx_pipe = usb_rcvbulkpipe(usbdev, 408 data_desc->endpoint[1].desc.bEndpointAddress); 409 pnd->tx_pipe = usb_sndbulkpipe(usbdev, 410 data_desc->endpoint[0].desc.bEndpointAddress); 411 } 412 pnd->active_setting = data_desc - data_intf->altsetting; 413 414 err = usb_driver_claim_interface(&usbpn_driver, data_intf, pnd); 415 if (err) 416 goto out; 417 418 /* Force inactive mode until the network device is brought UP */ 419 usb_set_interface(usbdev, union_header->bSlaveInterface0, 420 !pnd->active_setting); 421 usb_set_intfdata(intf, pnd); 422 423 err = register_netdev(dev); 424 if (err) { 425 usb_driver_release_interface(&usbpn_driver, data_intf); 426 goto out; 427 } 428 429 dev_dbg(&dev->dev, "USB CDC Phonet device found\n"); 430 return 0; 431 432 out: 433 usb_set_intfdata(intf, NULL); 434 free_netdev(dev); 435 return err; 436 } 437 438 static void usbpn_disconnect(struct usb_interface *intf) 439 { 440 struct usbpn_dev *pnd = usb_get_intfdata(intf); 441 struct usb_device *usb = pnd->usb; 442 443 if (pnd->disconnected) 444 return; 445 446 pnd->disconnected = 1; 447 usb_driver_release_interface(&usbpn_driver, 448 (pnd->intf == intf) ? pnd->data_intf : pnd->intf); 449 unregister_netdev(pnd->dev); 450 usb_put_dev(usb); 451 } 452 453 static struct usb_driver usbpn_driver = { 454 .name = "cdc_phonet", 455 .probe = usbpn_probe, 456 .disconnect = usbpn_disconnect, 457 .id_table = usbpn_ids, 458 }; 459 460 static int __init usbpn_init(void) 461 { 462 return usb_register(&usbpn_driver); 463 } 464 465 static void __exit usbpn_exit(void) 466 { 467 usb_deregister(&usbpn_driver); 468 } 469 470 module_init(usbpn_init); 471 module_exit(usbpn_exit); 472 473 MODULE_AUTHOR("Remi Denis-Courmont"); 474 MODULE_DESCRIPTION("USB CDC Phonet host interface"); 475 MODULE_LICENSE("GPL"); 476