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 unsigned long flags; 103 104 switch (status) { 105 case 0: 106 dev->stats.tx_bytes += skb->len; 107 break; 108 109 case -ENOENT: 110 case -ECONNRESET: 111 case -ESHUTDOWN: 112 dev->stats.tx_aborted_errors++; 113 /* fall through */ 114 default: 115 dev->stats.tx_errors++; 116 dev_dbg(&dev->dev, "TX error (%d)\n", status); 117 } 118 dev->stats.tx_packets++; 119 120 spin_lock_irqsave(&pnd->tx_lock, flags); 121 pnd->tx_queue--; 122 netif_wake_queue(dev); 123 spin_unlock_irqrestore(&pnd->tx_lock, flags); 124 125 dev_kfree_skb_any(skb); 126 usb_free_urb(req); 127 } 128 129 static int rx_submit(struct usbpn_dev *pnd, struct urb *req, gfp_t gfp_flags) 130 { 131 struct net_device *dev = pnd->dev; 132 struct page *page; 133 int err; 134 135 page = __dev_alloc_page(gfp_flags | __GFP_NOMEMALLOC); 136 if (!page) 137 return -ENOMEM; 138 139 usb_fill_bulk_urb(req, pnd->usb, pnd->rx_pipe, page_address(page), 140 PAGE_SIZE, rx_complete, dev); 141 req->transfer_flags = 0; 142 err = usb_submit_urb(req, gfp_flags); 143 if (unlikely(err)) { 144 dev_dbg(&dev->dev, "RX submit error (%d)\n", err); 145 put_page(page); 146 } 147 return err; 148 } 149 150 static void rx_complete(struct urb *req) 151 { 152 struct net_device *dev = req->context; 153 struct usbpn_dev *pnd = netdev_priv(dev); 154 struct page *page = virt_to_page(req->transfer_buffer); 155 struct sk_buff *skb; 156 unsigned long flags; 157 int status = req->status; 158 159 switch (status) { 160 case 0: 161 spin_lock_irqsave(&pnd->rx_lock, flags); 162 skb = pnd->rx_skb; 163 if (!skb) { 164 skb = pnd->rx_skb = netdev_alloc_skb(dev, 12); 165 if (likely(skb)) { 166 /* Can't use pskb_pull() on page in IRQ */ 167 skb_put_data(skb, page_address(page), 1); 168 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, 169 page, 1, req->actual_length, 170 PAGE_SIZE); 171 page = NULL; 172 } 173 } else { 174 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, 175 page, 0, req->actual_length, 176 PAGE_SIZE); 177 page = NULL; 178 } 179 if (req->actual_length < PAGE_SIZE) 180 pnd->rx_skb = NULL; /* Last fragment */ 181 else 182 skb = NULL; 183 spin_unlock_irqrestore(&pnd->rx_lock, flags); 184 if (skb) { 185 skb->protocol = htons(ETH_P_PHONET); 186 skb_reset_mac_header(skb); 187 __skb_pull(skb, 1); 188 skb->dev = dev; 189 dev->stats.rx_packets++; 190 dev->stats.rx_bytes += skb->len; 191 192 netif_rx(skb); 193 } 194 goto resubmit; 195 196 case -ENOENT: 197 case -ECONNRESET: 198 case -ESHUTDOWN: 199 req = NULL; 200 break; 201 202 case -EOVERFLOW: 203 dev->stats.rx_over_errors++; 204 dev_dbg(&dev->dev, "RX overflow\n"); 205 break; 206 207 case -EILSEQ: 208 dev->stats.rx_crc_errors++; 209 break; 210 } 211 212 dev->stats.rx_errors++; 213 resubmit: 214 if (page) 215 put_page(page); 216 if (req) 217 rx_submit(pnd, req, GFP_ATOMIC); 218 } 219 220 static int usbpn_close(struct net_device *dev); 221 222 static int usbpn_open(struct net_device *dev) 223 { 224 struct usbpn_dev *pnd = netdev_priv(dev); 225 int err; 226 unsigned i; 227 unsigned num = pnd->data_intf->cur_altsetting->desc.bInterfaceNumber; 228 229 err = usb_set_interface(pnd->usb, num, pnd->active_setting); 230 if (err) 231 return err; 232 233 for (i = 0; i < rxq_size; i++) { 234 struct urb *req = usb_alloc_urb(0, GFP_KERNEL); 235 236 if (!req || rx_submit(pnd, req, GFP_KERNEL)) { 237 usb_free_urb(req); 238 usbpn_close(dev); 239 return -ENOMEM; 240 } 241 pnd->urbs[i] = req; 242 } 243 244 netif_wake_queue(dev); 245 return 0; 246 } 247 248 static int usbpn_close(struct net_device *dev) 249 { 250 struct usbpn_dev *pnd = netdev_priv(dev); 251 unsigned i; 252 unsigned num = pnd->data_intf->cur_altsetting->desc.bInterfaceNumber; 253 254 netif_stop_queue(dev); 255 256 for (i = 0; i < rxq_size; i++) { 257 struct urb *req = pnd->urbs[i]; 258 259 if (!req) 260 continue; 261 usb_kill_urb(req); 262 usb_free_urb(req); 263 pnd->urbs[i] = NULL; 264 } 265 266 return usb_set_interface(pnd->usb, num, !pnd->active_setting); 267 } 268 269 static int usbpn_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 270 { 271 struct if_phonet_req *req = (struct if_phonet_req *)ifr; 272 273 switch (cmd) { 274 case SIOCPNGAUTOCONF: 275 req->ifr_phonet_autoconf.device = PN_DEV_PC; 276 return 0; 277 } 278 return -ENOIOCTLCMD; 279 } 280 281 static const struct net_device_ops usbpn_ops = { 282 .ndo_open = usbpn_open, 283 .ndo_stop = usbpn_close, 284 .ndo_start_xmit = usbpn_xmit, 285 .ndo_do_ioctl = usbpn_ioctl, 286 }; 287 288 static void usbpn_setup(struct net_device *dev) 289 { 290 dev->features = 0; 291 dev->netdev_ops = &usbpn_ops, 292 dev->header_ops = &phonet_header_ops; 293 dev->type = ARPHRD_PHONET; 294 dev->flags = IFF_POINTOPOINT | IFF_NOARP; 295 dev->mtu = PHONET_MAX_MTU; 296 dev->min_mtu = PHONET_MIN_MTU; 297 dev->max_mtu = PHONET_MAX_MTU; 298 dev->hard_header_len = 1; 299 dev->dev_addr[0] = PN_MEDIA_USB; 300 dev->addr_len = 1; 301 dev->tx_queue_len = 3; 302 303 dev->needs_free_netdev = true; 304 } 305 306 /* 307 * USB driver callbacks 308 */ 309 static const struct usb_device_id usbpn_ids[] = { 310 { 311 .match_flags = USB_DEVICE_ID_MATCH_VENDOR 312 | USB_DEVICE_ID_MATCH_INT_CLASS 313 | USB_DEVICE_ID_MATCH_INT_SUBCLASS, 314 .idVendor = 0x0421, /* Nokia */ 315 .bInterfaceClass = USB_CLASS_COMM, 316 .bInterfaceSubClass = 0xFE, 317 }, 318 { }, 319 }; 320 321 MODULE_DEVICE_TABLE(usb, usbpn_ids); 322 323 static struct usb_driver usbpn_driver; 324 325 static int usbpn_probe(struct usb_interface *intf, const struct usb_device_id *id) 326 { 327 static const char ifname[] = "usbpn%d"; 328 const struct usb_cdc_union_desc *union_header = NULL; 329 const struct usb_host_interface *data_desc; 330 struct usb_interface *data_intf; 331 struct usb_device *usbdev = interface_to_usbdev(intf); 332 struct net_device *dev; 333 struct usbpn_dev *pnd; 334 u8 *data; 335 int phonet = 0; 336 int len, err; 337 struct usb_cdc_parsed_header hdr; 338 339 data = intf->altsetting->extra; 340 len = intf->altsetting->extralen; 341 cdc_parse_cdc_header(&hdr, intf, data, len); 342 union_header = hdr.usb_cdc_union_desc; 343 phonet = hdr.phonet_magic_present; 344 345 if (!union_header || !phonet) 346 return -EINVAL; 347 348 data_intf = usb_ifnum_to_if(usbdev, union_header->bSlaveInterface0); 349 if (data_intf == NULL) 350 return -ENODEV; 351 /* Data interface has one inactive and one active setting */ 352 if (data_intf->num_altsetting != 2) 353 return -EINVAL; 354 if (data_intf->altsetting[0].desc.bNumEndpoints == 0 && 355 data_intf->altsetting[1].desc.bNumEndpoints == 2) 356 data_desc = data_intf->altsetting + 1; 357 else 358 if (data_intf->altsetting[0].desc.bNumEndpoints == 2 && 359 data_intf->altsetting[1].desc.bNumEndpoints == 0) 360 data_desc = data_intf->altsetting; 361 else 362 return -EINVAL; 363 364 dev = alloc_netdev(struct_size(pnd, urbs, rxq_size), ifname, 365 NET_NAME_UNKNOWN, usbpn_setup); 366 if (!dev) 367 return -ENOMEM; 368 369 pnd = netdev_priv(dev); 370 SET_NETDEV_DEV(dev, &intf->dev); 371 372 pnd->dev = dev; 373 pnd->usb = usbdev; 374 pnd->intf = intf; 375 pnd->data_intf = data_intf; 376 spin_lock_init(&pnd->tx_lock); 377 spin_lock_init(&pnd->rx_lock); 378 /* Endpoints */ 379 if (usb_pipein(data_desc->endpoint[0].desc.bEndpointAddress)) { 380 pnd->rx_pipe = usb_rcvbulkpipe(usbdev, 381 data_desc->endpoint[0].desc.bEndpointAddress); 382 pnd->tx_pipe = usb_sndbulkpipe(usbdev, 383 data_desc->endpoint[1].desc.bEndpointAddress); 384 } else { 385 pnd->rx_pipe = usb_rcvbulkpipe(usbdev, 386 data_desc->endpoint[1].desc.bEndpointAddress); 387 pnd->tx_pipe = usb_sndbulkpipe(usbdev, 388 data_desc->endpoint[0].desc.bEndpointAddress); 389 } 390 pnd->active_setting = data_desc - data_intf->altsetting; 391 392 err = usb_driver_claim_interface(&usbpn_driver, data_intf, pnd); 393 if (err) 394 goto out; 395 396 /* Force inactive mode until the network device is brought UP */ 397 usb_set_interface(usbdev, union_header->bSlaveInterface0, 398 !pnd->active_setting); 399 usb_set_intfdata(intf, pnd); 400 401 err = register_netdev(dev); 402 if (err) { 403 usb_driver_release_interface(&usbpn_driver, data_intf); 404 goto out; 405 } 406 407 dev_dbg(&dev->dev, "USB CDC Phonet device found\n"); 408 return 0; 409 410 out: 411 usb_set_intfdata(intf, NULL); 412 free_netdev(dev); 413 return err; 414 } 415 416 static void usbpn_disconnect(struct usb_interface *intf) 417 { 418 struct usbpn_dev *pnd = usb_get_intfdata(intf); 419 420 if (pnd->disconnected) 421 return; 422 423 pnd->disconnected = 1; 424 usb_driver_release_interface(&usbpn_driver, 425 (pnd->intf == intf) ? pnd->data_intf : pnd->intf); 426 unregister_netdev(pnd->dev); 427 } 428 429 static struct usb_driver usbpn_driver = { 430 .name = "cdc_phonet", 431 .probe = usbpn_probe, 432 .disconnect = usbpn_disconnect, 433 .id_table = usbpn_ids, 434 .disable_hub_initiated_lpm = 1, 435 }; 436 437 module_usb_driver(usbpn_driver); 438 439 MODULE_AUTHOR("Remi Denis-Courmont"); 440 MODULE_DESCRIPTION("USB CDC Phonet host interface"); 441 MODULE_LICENSE("GPL"); 442