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 =               __constant_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 =               __constant_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 =       __constant_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 =       __constant_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         if (netif_carrier_ok(dev))
 192                 netif_wake_queue(dev);
 193         return 0;
 194 }
 195
 196 static int pn_net_close(struct net_device *dev)
 197 {
 198         netif_stop_queue(dev);
 199         return 0;
 200 }
 201
 202 static void pn_tx_complete(struct usb_ep *ep, struct usb_request *req)
 203 {
 204         struct f_phonet *fp = ep->driver_data;
 205         struct net_device *dev = fp->dev;
 206         struct sk_buff *skb = req->context;
 207
 208         switch (req->status) {
 209         case 0:
 210                 dev->stats.tx_packets++;
 211                 dev->stats.tx_bytes += skb->len;
 212                 break;
 213
 214         case -ESHUTDOWN: /* disconnected */
 215         case -ECONNRESET: /* disabled */
 216                 dev->stats.tx_aborted_errors++;
 217         default:
 218                 dev->stats.tx_errors++;
 219         }
 220
 221         dev_kfree_skb_any(skb);
 222         if (netif_carrier_ok(dev))
 223                 netif_wake_queue(dev);
 224 }
 225
 226 static int pn_net_xmit(struct sk_buff *skb, struct net_device *dev)
 227 {
 228         struct phonet_port *port = netdev_priv(dev);
 229         struct f_phonet *fp;
 230         struct usb_request *req;
 231         unsigned long flags;
 232
 233         if (skb->protocol != htons(ETH_P_PHONET))
 234                 goto out;
 235
 236         spin_lock_irqsave(&port->lock, flags);
 237         fp = port->usb;
 238         if (unlikely(!fp)) /* race with carrier loss */
 239                 goto out_unlock;
 240
 241         req = fp->in_req;
 242         req->buf = skb->data;
 243         req->length = skb->len;
 244         req->complete = pn_tx_complete;
 245         req->zero = 1;
 246         req->context = skb;
 247
 248         if (unlikely(usb_ep_queue(fp->in_ep, req, GFP_ATOMIC)))
 249                 goto out_unlock;
 250
 251         netif_stop_queue(dev);
 252         skb = NULL;
 253
 254 out_unlock:
 255         spin_unlock_irqrestore(&port->lock, flags);
 256 out:
 257         if (unlikely(skb)) {
 258                 dev_kfree_skb_any(skb);
 259                 dev->stats.tx_dropped++;
 260         }
 261         return 0;
 262 }
 263
 264 static int pn_net_mtu(struct net_device *dev, int new_mtu)
 265 {
 266         struct phonet_port *port = netdev_priv(dev);
 267         unsigned long flags;
 268         int err = -EBUSY;
 269
 270         if ((new_mtu < PHONET_MIN_MTU) || (new_mtu > PHONET_MAX_MTU))
 271                 return -EINVAL;
 272
 273         spin_lock_irqsave(&port->lock, flags);
 274         if (!netif_carrier_ok(dev)) {
 275                 dev->mtu = new_mtu;
 276                 err = 0;
 277         }
 278         spin_unlock_irqrestore(&port->lock, flags);
 279         return err;
 280 }
 281
 282 static const struct net_device_ops pn_netdev_ops = {
 283         .ndo_open       = pn_net_open,
 284         .ndo_stop       = pn_net_close,
 285         .ndo_start_xmit = pn_net_xmit,
 286         .ndo_change_mtu = pn_net_mtu,
 287 };
 288
 289 static void pn_net_setup(struct net_device *dev)
 290 {
 291         dev->features           = 0;
 292         dev->type               = ARPHRD_PHONET;
 293         dev->flags              = IFF_POINTOPOINT | IFF_NOARP;
 294         dev->mtu                = PHONET_DEV_MTU;
 295         dev->hard_header_len    = 1;
 296         dev->dev_addr[0]        = PN_MEDIA_USB;
 297         dev->addr_len           = 1;
 298         dev->tx_queue_len       = 1;
 299
 300         dev->netdev_ops         = &pn_netdev_ops;
 301         dev->destructor         = free_netdev;
 302         dev->header_ops         = &phonet_header_ops;
 303 }
 304
 305 /*-------------------------------------------------------------------------*/
 306
 307 /*
 308  * Queue buffer for data from the host
 309  */
 310 static int
 311 pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags)
 312 {
 313         struct sk_buff *skb;
 314         const size_t size = fp->dev->mtu;
 315         int err;
 316
 317         skb = alloc_skb(size, gfp_flags);
 318         if (!skb)
 319                 return -ENOMEM;
 320
 321         req->buf = skb->data;
 322         req->length = size;
 323         req->context = skb;
 324
 325         err = usb_ep_queue(fp->out_ep, req, gfp_flags);
 326         if (unlikely(err))
 327                 dev_kfree_skb_any(skb);
 328         return err;
 329 }
 330
 331 static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
 332 {
 333         struct f_phonet *fp = ep->driver_data;
 334         struct net_device *dev = fp->dev;
 335         struct sk_buff *skb = req->context;
 336         int status = req->status;
 337
 338         switch (status) {
 339         case 0:
 340                 if (unlikely(!netif_running(dev)))
 341                         break;
 342                 if (unlikely(req->actual < 1))
 343                         break;
 344                 skb_put(skb, req->actual);
 345                 skb->protocol = htons(ETH_P_PHONET);
 346                 skb_reset_mac_header(skb);
 347                 __skb_pull(skb, 1);
 348                 skb->dev = dev;
 349                 dev->stats.rx_packets++;
 350                 dev->stats.rx_bytes += skb->len;
 351
 352                 netif_rx(skb);
 353                 skb = NULL;
 354                 break;
 355
 356         /* Do not resubmit in these cases: */
 357         case -ESHUTDOWN: /* disconnect */
 358         case -ECONNABORTED: /* hw reset */
 359         case -ECONNRESET: /* dequeued (unlink or netif down) */
 360                 req = NULL;
 361                 break;
 362
 363         /* Do resubmit in these cases: */
 364         case -EOVERFLOW: /* request buffer overflow */
 365                 dev->stats.rx_over_errors++;
 366         default:
 367                 dev->stats.rx_errors++;
 368                 break;
 369         }
 370
 371         if (skb)
 372                 dev_kfree_skb_any(skb);
 373         if (req)
 374                 pn_rx_submit(fp, req, GFP_ATOMIC);
 375 }
 376
 377 /*-------------------------------------------------------------------------*/
 378
 379 static void __pn_reset(struct usb_function *f)
 380 {
 381         struct f_phonet *fp = func_to_pn(f);
 382         struct net_device *dev = fp->dev;
 383         struct phonet_port *port = netdev_priv(dev);
 384
 385         netif_carrier_off(dev);
 386         netif_stop_queue(dev);
 387         port->usb = NULL;
 388
 389         usb_ep_disable(fp->out_ep);
 390         usb_ep_disable(fp->in_ep);
 391 }
 392
 393 static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 394 {
 395         struct f_phonet *fp = func_to_pn(f);
 396         struct usb_gadget *gadget = fp->function.config->cdev->gadget;
 397
 398         if (intf == pn_control_intf_desc.bInterfaceNumber)
 399                 /* control interface, no altsetting */
 400                 return (alt > 0) ? -EINVAL : 0;
 401
 402         if (intf == pn_data_intf_desc.bInterfaceNumber) {
 403                 struct net_device *dev = fp->dev;
 404                 struct phonet_port *port = netdev_priv(dev);
 405
 406                 /* data intf (0: inactive, 1: active) */
 407                 if (alt > 1)
 408                         return -EINVAL;
 409
 410                 spin_lock(&port->lock);
 411                 __pn_reset(f);
 412                 if (alt == 1) {
 413                         struct usb_endpoint_descriptor *out, *in;
 414                         int i;
 415
 416                         out = ep_choose(gadget,
 417                                         &pn_hs_sink_desc,
 418                                         &pn_fs_sink_desc);
 419                         in = ep_choose(gadget,
 420                                         &pn_hs_source_desc,
 421                                         &pn_fs_source_desc);
 422                         usb_ep_enable(fp->out_ep, out);
 423                         usb_ep_enable(fp->in_ep, in);
 424
 425                         port->usb = fp;
 426                         fp->out_ep->driver_data = fp;
 427                         fp->in_ep->driver_data = fp;
 428
 429                         netif_carrier_on(dev);
 430                         if (netif_running(dev))
 431                                 netif_wake_queue(dev);
 432                         for (i = 0; i < phonet_rxq_size; i++)
 433                                 pn_rx_submit(fp, fp->out_reqv[i], GFP_ATOMIC);
 434                 }
 435                 spin_unlock(&port->lock);
 436                 return 0;
 437         }
 438
 439         return -EINVAL;
 440 }
 441
 442 static int pn_get_alt(struct usb_function *f, unsigned intf)
 443 {
 444         struct f_phonet *fp = func_to_pn(f);
 445
 446         if (intf == pn_control_intf_desc.bInterfaceNumber)
 447                 return 0;
 448
 449         if (intf == pn_data_intf_desc.bInterfaceNumber) {
 450                 struct phonet_port *port = netdev_priv(fp->dev);
 451                 u8 alt;
 452
 453                 spin_lock(&port->lock);
 454                 alt = port->usb != NULL;
 455                 spin_unlock(&port->lock);
 456                 return alt;
 457         }
 458
 459         return -EINVAL;
 460 }
 461
 462 static void pn_disconnect(struct usb_function *f)
 463 {
 464         struct f_phonet *fp = func_to_pn(f);
 465         struct phonet_port *port = netdev_priv(fp->dev);
 466         unsigned long flags;
 467
 468         /* remain disabled until set_alt */
 469         spin_lock_irqsave(&port->lock, flags);
 470         __pn_reset(f);
 471         spin_unlock_irqrestore(&port->lock, flags);
 472 }
 473
 474 /*-------------------------------------------------------------------------*/
 475
 476 static __init
 477 int pn_bind(struct usb_configuration *c, struct usb_function *f)
 478 {
 479         struct usb_composite_dev *cdev = c->cdev;
 480         struct usb_gadget *gadget = cdev->gadget;
 481         struct f_phonet *fp = func_to_pn(f);
 482         struct usb_ep *ep;
 483         int status, i;
 484
 485         /* Reserve interface IDs */
 486         status = usb_interface_id(c, f);
 487         if (status < 0)
 488                 goto err;
 489         pn_control_intf_desc.bInterfaceNumber = status;
 490         pn_union_desc.bMasterInterface0 = status;
 491
 492         status = usb_interface_id(c, f);
 493         if (status < 0)
 494                 goto err;
 495         pn_data_nop_intf_desc.bInterfaceNumber = status;
 496         pn_data_intf_desc.bInterfaceNumber = status;
 497         pn_union_desc.bSlaveInterface0 = status;
 498
 499         /* Reserve endpoints */
 500         status = -ENODEV;
 501         ep = usb_ep_autoconfig(gadget, &pn_fs_sink_desc);
 502         if (!ep)
 503                 goto err;
 504         fp->out_ep = ep;
 505         ep->driver_data = fp; /* Claim */
 506
 507         ep = usb_ep_autoconfig(gadget, &pn_fs_source_desc);
 508         if (!ep)
 509                 goto err;
 510         fp->in_ep = ep;
 511         ep->driver_data = fp; /* Claim */
 512
 513         pn_hs_sink_desc.bEndpointAddress =
 514                 pn_fs_sink_desc.bEndpointAddress;
 515         pn_hs_source_desc.bEndpointAddress =
 516                 pn_fs_source_desc.bEndpointAddress;
 517
 518         /* Do not try to bind Phonet twice... */
 519         fp->function.descriptors = fs_pn_function;
 520         fp->function.hs_descriptors = hs_pn_function;
 521
 522         /* Incoming USB requests */
 523         status = -ENOMEM;
 524         for (i = 0; i < phonet_rxq_size; i++) {
 525                 struct usb_request *req;
 526
 527                 req = usb_ep_alloc_request(fp->out_ep, GFP_KERNEL);
 528                 if (!req)
 529                         goto err;
 530
 531                 req->complete = pn_rx_complete;
 532                 fp->out_reqv[i] = req;
 533         }
 534
 535         /* Outgoing USB requests */
 536         fp->in_req = usb_ep_alloc_request(fp->in_ep, GFP_KERNEL);
 537         if (!fp->in_req)
 538                 goto err;
 539
 540         INFO(cdev, "USB CDC Phonet function\n");
 541         INFO(cdev, "using %s, OUT %s, IN %s\n", cdev->gadget->name,
 542                 fp->out_ep->name, fp->in_ep->name);
 543         return 0;
 544
 545 err:
 546         if (fp->out_ep)
 547                 fp->out_ep->driver_data = NULL;
 548         if (fp->in_ep)
 549                 fp->in_ep->driver_data = NULL;
 550         ERROR(cdev, "USB CDC Phonet: cannot autoconfigure\n");
 551         return status;
 552 }
 553
 554 static void
 555 pn_unbind(struct usb_configuration *c, struct usb_function *f)
 556 {
 557         struct f_phonet *fp = func_to_pn(f);
 558         int i;
 559
 560         /* We are already disconnected */
 561         if (fp->in_req)
 562                 usb_ep_free_request(fp->in_ep, fp->in_req);
 563         for (i = 0; i < phonet_rxq_size; i++)
 564                 if (fp->out_reqv[i])
 565                         usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
 566
 567         kfree(fp);
 568 }
 569
 570 /*-------------------------------------------------------------------------*/
 571
 572 static struct net_device *dev;
 573
 574 int __init phonet_bind_config(struct usb_configuration *c)
 575 {
 576         struct f_phonet *fp;
 577         int err;
 578
 579         fp = kzalloc(sizeof(*fp), GFP_KERNEL);
 580         if (!fp)
 581                 return -ENOMEM;
 582
 583         fp->dev = dev;
 584         fp->function.name = "phonet";
 585         fp->function.bind = pn_bind;
 586         fp->function.unbind = pn_unbind;
 587         fp->function.set_alt = pn_set_alt;
 588         fp->function.get_alt = pn_get_alt;
 589         fp->function.disable = pn_disconnect;
 590
 591         err = usb_add_function(c, &fp->function);
 592         if (err)
 593                 kfree(fp);
 594         return err;
 595 }
 596
 597 int __init gphonet_setup(struct usb_gadget *gadget)
 598 {
 599         struct phonet_port *port;
 600         int err;
 601
 602         /* Create net device */
 603         BUG_ON(dev);
 604         dev = alloc_netdev(sizeof(*port)
 605                 + (phonet_rxq_size * sizeof(struct usb_request *)),
 606                                 "upnlink%d", pn_net_setup);
 607         if (!dev)
 608                 return -ENOMEM;
 609
 610         port = netdev_priv(dev);
 611         spin_lock_init(&port->lock);
 612         netif_carrier_off(dev);
 613         netif_stop_queue(dev);
 614         SET_NETDEV_DEV(dev, &gadget->dev);
 615
 616         err = register_netdev(dev);
 617         if (err)
 618                 free_netdev(dev);
 619         return err;
 620 }
 621
 622 void gphonet_cleanup(void)
 623 {
 624         unregister_netdev(dev);
 625 }