drivers/usb/gadget/f_phonet.c

   1 /*
   2  * f_phonet.c -- USB CDC Phonet function
   3  *
   4  * Copyright (C) 2007-2008 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/device.h>
  25
  26 #include <linux/netdevice.h>
  27 #include <linux/if_ether.h>
  28 #include <linux/if_phonet.h>
  29 #include <linux/if_arp.h>
  30
  31 #include <linux/usb/ch9.h>
  32 #include <linux/usb/cdc.h>
  33 #include <linux/usb/composite.h>
  34
  35 #include "u_phonet.h"
  36
  37 #define PN_MEDIA_USB    0x1B
  38
  39 /*-------------------------------------------------------------------------*/
  40
  41 struct phonet_port {
  42         struct f_phonet                 *usb;
  43         spinlock_t                      lock;
  44 };
  45
  46 struct f_phonet {
  47         struct usb_function             function;
  48         struct net_device               *dev;
  49         struct usb_ep                   *in_ep, *out_ep;
  50
  51         struct usb_request              *in_req;
  52         struct usb_request              *out_reqv[0];
  53 };
  54
  55 static int phonet_rxq_size = 2;
  56
  57 static inline struct f_phonet *func_to_pn(struct usb_function *f)
  58 {
  59         return container_of(f, struct f_phonet, function);
  60 }
  61
  62 /*-------------------------------------------------------------------------*/
  63
  64 #define USB_CDC_SUBCLASS_PHONET 0xfe
  65 #define USB_CDC_PHONET_TYPE     0xab
  66
  67 static struct usb_interface_descriptor
  68 pn_control_intf_desc = {
  69         .bLength =              sizeof pn_control_intf_desc,
  70         .bDescriptorType =      USB_DT_INTERFACE,
  71
  72         /* .bInterfaceNumber =  DYNAMIC, */
  73         .bInterfaceClass =      USB_CLASS_COMM,
  74         .bInterfaceSubClass =   USB_CDC_SUBCLASS_PHONET,
  75 };
  76
  77 static const struct usb_cdc_header_desc
  78 pn_header_desc = {
  79         .bLength =              sizeof pn_header_desc,
  80         .bDescriptorType =      USB_DT_CS_INTERFACE,
  81         .bDescriptorSubType =   USB_CDC_HEADER_TYPE,
  82         .bcdCDC =               cpu_to_le16(0x0110),
  83 };
  84
  85 static const struct usb_cdc_header_desc
  86 pn_phonet_desc = {
  87         .bLength =              sizeof pn_phonet_desc,
  88         .bDescriptorType =      USB_DT_CS_INTERFACE,
  89         .bDescriptorSubType =   USB_CDC_PHONET_TYPE,
  90         .bcdCDC =               cpu_to_le16(0x1505), /* ??? */
  91 };
  92
  93 static struct usb_cdc_union_desc
  94 pn_union_desc = {
  95         .bLength =              sizeof pn_union_desc,
  96         .bDescriptorType =      USB_DT_CS_INTERFACE,
  97         .bDescriptorSubType =   USB_CDC_UNION_TYPE,
  98
  99         /* .bMasterInterface0 = DYNAMIC, */
 100         /* .bSlaveInterface0 =  DYNAMIC, */
 101 };
 102
 103 static struct usb_interface_descriptor
 104 pn_data_nop_intf_desc = {
 105         .bLength =              sizeof pn_data_nop_intf_desc,
 106         .bDescriptorType =      USB_DT_INTERFACE,
 107
 108         /* .bInterfaceNumber =  DYNAMIC, */
 109         .bAlternateSetting =    0,
 110         .bNumEndpoints =        0,
 111         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 112 };
 113
 114 static struct usb_interface_descriptor
 115 pn_data_intf_desc = {
 116         .bLength =              sizeof pn_data_intf_desc,
 117         .bDescriptorType =      USB_DT_INTERFACE,
 118
 119         /* .bInterfaceNumber =  DYNAMIC, */
 120         .bAlternateSetting =    1,
 121         .bNumEndpoints =        2,
 122         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 123 };
 124
 125 static struct usb_endpoint_descriptor
 126 pn_fs_sink_desc = {
 127         .bLength =              USB_DT_ENDPOINT_SIZE,
 128         .bDescriptorType =      USB_DT_ENDPOINT,
 129
 130         .bEndpointAddress =     USB_DIR_OUT,
 131         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 132 };
 133
 134 static struct usb_endpoint_descriptor
 135 pn_hs_sink_desc = {
 136         .bLength =              USB_DT_ENDPOINT_SIZE,
 137         .bDescriptorType =      USB_DT_ENDPOINT,
 138
 139         .bEndpointAddress =     USB_DIR_OUT,
 140         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 141         .wMaxPacketSize =       cpu_to_le16(512),
 142 };
 143
 144 static struct usb_endpoint_descriptor
 145 pn_fs_source_desc = {
 146         .bLength =              USB_DT_ENDPOINT_SIZE,
 147         .bDescriptorType =      USB_DT_ENDPOINT,
 148
 149         .bEndpointAddress =     USB_DIR_IN,
 150         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 151 };
 152
 153 static struct usb_endpoint_descriptor
 154 pn_hs_source_desc = {
 155         .bLength =              USB_DT_ENDPOINT_SIZE,
 156         .bDescriptorType =      USB_DT_ENDPOINT,
 157
 158         .bEndpointAddress =     USB_DIR_IN,
 159         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 160         .wMaxPacketSize =       cpu_to_le16(512),
 161 };
 162
 163 static struct usb_descriptor_header *fs_pn_function[] = {
 164         (struct usb_descriptor_header *) &pn_control_intf_desc,
 165         (struct usb_descriptor_header *) &pn_header_desc,
 166         (struct usb_descriptor_header *) &pn_phonet_desc,
 167         (struct usb_descriptor_header *) &pn_union_desc,
 168         (struct usb_descriptor_header *) &pn_data_nop_intf_desc,
 169         (struct usb_descriptor_header *) &pn_data_intf_desc,
 170         (struct usb_descriptor_header *) &pn_fs_sink_desc,
 171         (struct usb_descriptor_header *) &pn_fs_source_desc,
 172         NULL,
 173 };
 174
 175 static struct usb_descriptor_header *hs_pn_function[] = {
 176         (struct usb_descriptor_header *) &pn_control_intf_desc,
 177         (struct usb_descriptor_header *) &pn_header_desc,
 178         (struct usb_descriptor_header *) &pn_phonet_desc,
 179         (struct usb_descriptor_header *) &pn_union_desc,
 180         (struct usb_descriptor_header *) &pn_data_nop_intf_desc,
 181         (struct usb_descriptor_header *) &pn_data_intf_desc,
 182         (struct usb_descriptor_header *) &pn_hs_sink_desc,
 183         (struct usb_descriptor_header *) &pn_hs_source_desc,
 184         NULL,
 185 };
 186
 187 /*-------------------------------------------------------------------------*/
 188
 189 static int pn_net_open(struct net_device *dev)
 190 {
 191         netif_wake_queue(dev);
 192         return 0;
 193 }
 194
 195 static int pn_net_close(struct net_device *dev)
 196 {
 197         netif_stop_queue(dev);
 198         return 0;
 199 }
 200
 201 static void pn_tx_complete(struct usb_ep *ep, struct usb_request *req)
 202 {
 203         struct f_phonet *fp = ep->driver_data;
 204         struct net_device *dev = fp->dev;
 205         struct sk_buff *skb = req->context;
 206
 207         switch (req->status) {
 208         case 0:
 209                 dev->stats.tx_packets++;
 210                 dev->stats.tx_bytes += skb->len;
 211                 break;
 212
 213         case -ESHUTDOWN: /* disconnected */
 214         case -ECONNRESET: /* disabled */
 215                 dev->stats.tx_aborted_errors++;
 216         default:
 217                 dev->stats.tx_errors++;
 218         }
 219
 220         dev_kfree_skb_any(skb);
 221         netif_wake_queue(dev);
 222 }
 223
 224 static int pn_net_xmit(struct sk_buff *skb, struct net_device *dev)
 225 {
 226         struct phonet_port *port = netdev_priv(dev);
 227         struct f_phonet *fp;
 228         struct usb_request *req;
 229         unsigned long flags;
 230
 231         if (skb->protocol != htons(ETH_P_PHONET))
 232                 goto out;
 233
 234         spin_lock_irqsave(&port->lock, flags);
 235         fp = port->usb;
 236         if (unlikely(!fp)) /* race with carrier loss */
 237                 goto out_unlock;
 238
 239         req = fp->in_req;
 240         req->buf = skb->data;
 241         req->length = skb->len;
 242         req->complete = pn_tx_complete;
 243         req->zero = 1;
 244         req->context = skb;
 245
 246         if (unlikely(usb_ep_queue(fp->in_ep, req, GFP_ATOMIC)))
 247                 goto out_unlock;
 248
 249         netif_stop_queue(dev);
 250         skb = NULL;
 251
 252 out_unlock:
 253         spin_unlock_irqrestore(&port->lock, flags);
 254 out:
 255         if (unlikely(skb)) {
 256                 dev_kfree_skb(skb);
 257                 dev->stats.tx_dropped++;
 258         }
 259         return 0;
 260 }
 261
 262 static int pn_net_mtu(struct net_device *dev, int new_mtu)
 263 {
 264         struct phonet_port *port = netdev_priv(dev);
 265         unsigned long flags;
 266         int err = -EBUSY;
 267
 268         if ((new_mtu < PHONET_MIN_MTU) || (new_mtu > PHONET_MAX_MTU))
 269                 return -EINVAL;
 270
 271         spin_lock_irqsave(&port->lock, flags);
 272         if (!netif_carrier_ok(dev)) {
 273                 dev->mtu = new_mtu;
 274                 err = 0;
 275         }
 276         spin_unlock_irqrestore(&port->lock, flags);
 277         return err;
 278 }
 279
 280 static const struct net_device_ops pn_netdev_ops = {
 281         .ndo_open       = pn_net_open,
 282         .ndo_stop       = pn_net_close,
 283         .ndo_start_xmit = pn_net_xmit,
 284         .ndo_change_mtu = pn_net_mtu,
 285 };
 286
 287 static void pn_net_setup(struct net_device *dev)
 288 {
 289         dev->features           = 0;
 290         dev->type               = ARPHRD_PHONET;
 291         dev->flags              = IFF_POINTOPOINT | IFF_NOARP;
 292         dev->mtu                = PHONET_DEV_MTU;
 293         dev->hard_header_len    = 1;
 294         dev->dev_addr[0]        = PN_MEDIA_USB;
 295         dev->addr_len           = 1;
 296         dev->tx_queue_len       = 1;
 297
 298         dev->netdev_ops         = &pn_netdev_ops;
 299         dev->destructor         = free_netdev;
 300         dev->header_ops         = &phonet_header_ops;
 301 }
 302
 303 /*-------------------------------------------------------------------------*/
 304
 305 /*
 306  * Queue buffer for data from the host
 307  */
 308 static int
 309 pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags)
 310 {
 311         struct sk_buff *skb;
 312         const size_t size = fp->dev->mtu;
 313         int err;
 314
 315         skb = alloc_skb(size, gfp_flags);
 316         if (!skb)
 317                 return -ENOMEM;
 318
 319         req->buf = skb->data;
 320         req->length = size;
 321         req->context = skb;
 322
 323         err = usb_ep_queue(fp->out_ep, req, gfp_flags);
 324         if (unlikely(err))
 325                 dev_kfree_skb_any(skb);
 326         return err;
 327 }
 328
 329 static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
 330 {
 331         struct f_phonet *fp = ep->driver_data;
 332         struct net_device *dev = fp->dev;
 333         struct sk_buff *skb = req->context;
 334         int status = req->status;
 335
 336         switch (status) {
 337         case 0:
 338                 if (unlikely(!netif_running(dev)))
 339                         break;
 340                 if (unlikely(req->actual < 1))
 341                         break;
 342                 skb_put(skb, req->actual);
 343                 skb->protocol = htons(ETH_P_PHONET);
 344                 skb_reset_mac_header(skb);
 345                 __skb_pull(skb, 1);
 346                 skb->dev = dev;
 347                 dev->stats.rx_packets++;
 348                 dev->stats.rx_bytes += skb->len;
 349
 350                 netif_rx(skb);
 351                 skb = NULL;
 352                 break;
 353
 354         /* Do not resubmit in these cases: */
 355         case -ESHUTDOWN: /* disconnect */
 356         case -ECONNABORTED: /* hw reset */
 357         case -ECONNRESET: /* dequeued (unlink or netif down) */
 358                 req = NULL;
 359                 break;
 360
 361         /* Do resubmit in these cases: */
 362         case -EOVERFLOW: /* request buffer overflow */
 363                 dev->stats.rx_over_errors++;
 364         default:
 365                 dev->stats.rx_errors++;
 366                 break;
 367         }
 368
 369         if (skb)
 370                 dev_kfree_skb_any(skb);
 371         if (req)
 372                 pn_rx_submit(fp, req, GFP_ATOMIC);
 373 }
 374
 375 /*-------------------------------------------------------------------------*/
 376
 377 static void __pn_reset(struct usb_function *f)
 378 {
 379         struct f_phonet *fp = func_to_pn(f);
 380         struct net_device *dev = fp->dev;
 381         struct phonet_port *port = netdev_priv(dev);
 382
 383         netif_carrier_off(dev);
 384         port->usb = NULL;
 385
 386         usb_ep_disable(fp->out_ep);
 387         usb_ep_disable(fp->in_ep);
 388 }
 389
 390 static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 391 {
 392         struct f_phonet *fp = func_to_pn(f);
 393         struct usb_gadget *gadget = fp->function.config->cdev->gadget;
 394
 395         if (intf == pn_control_intf_desc.bInterfaceNumber)
 396                 /* control interface, no altsetting */
 397                 return (alt > 0) ? -EINVAL : 0;
 398
 399         if (intf == pn_data_intf_desc.bInterfaceNumber) {
 400                 struct net_device *dev = fp->dev;
 401                 struct phonet_port *port = netdev_priv(dev);
 402
 403                 /* data intf (0: inactive, 1: active) */
 404                 if (alt > 1)
 405                         return -EINVAL;
 406
 407                 spin_lock(&port->lock);
 408                 __pn_reset(f);
 409                 if (alt == 1) {
 410                         struct usb_endpoint_descriptor *out, *in;
 411                         int i;
 412
 413                         out = ep_choose(gadget,
 414                                         &pn_hs_sink_desc,
 415                                         &pn_fs_sink_desc);
 416                         in = ep_choose(gadget,
 417                                         &pn_hs_source_desc,
 418                                         &pn_fs_source_desc);
 419                         usb_ep_enable(fp->out_ep, out);
 420                         usb_ep_enable(fp->in_ep, in);
 421
 422                         port->usb = fp;
 423                         fp->out_ep->driver_data = fp;
 424                         fp->in_ep->driver_data = fp;
 425
 426                         netif_carrier_on(dev);
 427                         for (i = 0; i < phonet_rxq_size; i++)
 428                                 pn_rx_submit(fp, fp->out_reqv[i], GFP_ATOMIC);
 429                 }
 430                 spin_unlock(&port->lock);
 431                 return 0;
 432         }
 433
 434         return -EINVAL;
 435 }
 436
 437 static int pn_get_alt(struct usb_function *f, unsigned intf)
 438 {
 439         struct f_phonet *fp = func_to_pn(f);
 440
 441         if (intf == pn_control_intf_desc.bInterfaceNumber)
 442                 return 0;
 443
 444         if (intf == pn_data_intf_desc.bInterfaceNumber) {
 445                 struct phonet_port *port = netdev_priv(fp->dev);
 446                 u8 alt;
 447
 448                 spin_lock(&port->lock);
 449                 alt = port->usb != NULL;
 450                 spin_unlock(&port->lock);
 451                 return alt;
 452         }
 453
 454         return -EINVAL;
 455 }
 456
 457 static void pn_disconnect(struct usb_function *f)
 458 {
 459         struct f_phonet *fp = func_to_pn(f);
 460         struct phonet_port *port = netdev_priv(fp->dev);
 461         unsigned long flags;
 462
 463         /* remain disabled until set_alt */
 464         spin_lock_irqsave(&port->lock, flags);
 465         __pn_reset(f);
 466         spin_unlock_irqrestore(&port->lock, flags);
 467 }
 468
 469 /*-------------------------------------------------------------------------*/
 470
 471 static __init
 472 int pn_bind(struct usb_configuration *c, struct usb_function *f)
 473 {
 474         struct usb_composite_dev *cdev = c->cdev;
 475         struct usb_gadget *gadget = cdev->gadget;
 476         struct f_phonet *fp = func_to_pn(f);
 477         struct usb_ep *ep;
 478         int status, i;
 479
 480         /* Reserve interface IDs */
 481         status = usb_interface_id(c, f);
 482         if (status < 0)
 483                 goto err;
 484         pn_control_intf_desc.bInterfaceNumber = status;
 485         pn_union_desc.bMasterInterface0 = status;
 486
 487         status = usb_interface_id(c, f);
 488         if (status < 0)
 489                 goto err;
 490         pn_data_nop_intf_desc.bInterfaceNumber = status;
 491         pn_data_intf_desc.bInterfaceNumber = status;
 492         pn_union_desc.bSlaveInterface0 = status;
 493
 494         /* Reserve endpoints */
 495         status = -ENODEV;
 496         ep = usb_ep_autoconfig(gadget, &pn_fs_sink_desc);
 497         if (!ep)
 498                 goto err;
 499         fp->out_ep = ep;
 500         ep->driver_data = fp; /* Claim */
 501
 502         ep = usb_ep_autoconfig(gadget, &pn_fs_source_desc);
 503         if (!ep)
 504                 goto err;
 505         fp->in_ep = ep;
 506         ep->driver_data = fp; /* Claim */
 507
 508         pn_hs_sink_desc.bEndpointAddress =
 509                 pn_fs_sink_desc.bEndpointAddress;
 510         pn_hs_source_desc.bEndpointAddress =
 511                 pn_fs_source_desc.bEndpointAddress;
 512
 513         /* Do not try to bind Phonet twice... */
 514         fp->function.descriptors = fs_pn_function;
 515         fp->function.hs_descriptors = hs_pn_function;
 516
 517         /* Incoming USB requests */
 518         status = -ENOMEM;
 519         for (i = 0; i < phonet_rxq_size; i++) {
 520                 struct usb_request *req;
 521
 522                 req = usb_ep_alloc_request(fp->out_ep, GFP_KERNEL);
 523                 if (!req)
 524                         goto err;
 525
 526                 req->complete = pn_rx_complete;
 527                 fp->out_reqv[i] = req;
 528         }
 529
 530         /* Outgoing USB requests */
 531         fp->in_req = usb_ep_alloc_request(fp->in_ep, GFP_KERNEL);
 532         if (!fp->in_req)
 533                 goto err;
 534
 535         INFO(cdev, "USB CDC Phonet function\n");
 536         INFO(cdev, "using %s, OUT %s, IN %s\n", cdev->gadget->name,
 537                 fp->out_ep->name, fp->in_ep->name);
 538         return 0;
 539
 540 err:
 541         if (fp->out_ep)
 542                 fp->out_ep->driver_data = NULL;
 543         if (fp->in_ep)
 544                 fp->in_ep->driver_data = NULL;
 545         ERROR(cdev, "USB CDC Phonet: cannot autoconfigure\n");
 546         return status;
 547 }
 548
 549 static void
 550 pn_unbind(struct usb_configuration *c, struct usb_function *f)
 551 {
 552         struct f_phonet *fp = func_to_pn(f);
 553         int i;
 554
 555         /* We are already disconnected */
 556         if (fp->in_req)
 557                 usb_ep_free_request(fp->in_ep, fp->in_req);
 558         for (i = 0; i < phonet_rxq_size; i++)
 559                 if (fp->out_reqv[i])
 560                         usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
 561
 562         kfree(fp);
 563 }
 564
 565 /*-------------------------------------------------------------------------*/
 566
 567 static struct net_device *dev;
 568
 569 int __init phonet_bind_config(struct usb_configuration *c)
 570 {
 571         struct f_phonet *fp;
 572         int err, size;
 573
 574         size = sizeof(*fp) + (phonet_rxq_size * sizeof(struct usb_request *));
 575         fp = kzalloc(size, GFP_KERNEL);
 576         if (!fp)
 577                 return -ENOMEM;
 578
 579         fp->dev = dev;
 580         fp->function.name = "phonet";
 581         fp->function.bind = pn_bind;
 582         fp->function.unbind = pn_unbind;
 583         fp->function.set_alt = pn_set_alt;
 584         fp->function.get_alt = pn_get_alt;
 585         fp->function.disable = pn_disconnect;
 586
 587         err = usb_add_function(c, &fp->function);
 588         if (err)
 589                 kfree(fp);
 590         return err;
 591 }
 592
 593 int __init gphonet_setup(struct usb_gadget *gadget)
 594 {
 595         struct phonet_port *port;
 596         int err;
 597
 598         /* Create net device */
 599         BUG_ON(dev);
 600         dev = alloc_netdev(sizeof(*port), "upnlink%d", pn_net_setup);
 601         if (!dev)
 602                 return -ENOMEM;
 603
 604         port = netdev_priv(dev);
 605         spin_lock_init(&port->lock);
 606         netif_carrier_off(dev);
 607         SET_NETDEV_DEV(dev, &gadget->dev);
 608
 609         err = register_netdev(dev);
 610         if (err)
 611                 free_netdev(dev);
 612         return err;
 613 }
 614
 615 void gphonet_cleanup(void)
 616 {
 617         unregister_netdev(dev);
 618 }