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