drivers/net/usb/cdc-phonet.c

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