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/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 module_usb_driver(usbpn_driver);
 461
 462 MODULE_AUTHOR("Remi Denis-Courmont");
 463 MODULE_DESCRIPTION("USB CDC Phonet host interface");
 464 MODULE_LICENSE("GPL");