drivers/usb/gadget/legacy/g_ffs.c

   1 /*
   2  * g_ffs.c -- user mode file system API for USB composite function controllers
   3  *
   4  * Copyright (C) 2010 Samsung Electronics
   5  * Author: Michal Nazarewicz <mina86@mina86.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  */
  12
  13 #define pr_fmt(fmt) "g_ffs: " fmt
  14
  15 #include <linux/module.h>
  16
  17 #if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
  18 #include <linux/netdevice.h>
  19
  20 #  if defined USB_ETH_RNDIS
  21 #    undef USB_ETH_RNDIS
  22 #  endif
  23 #  ifdef CONFIG_USB_FUNCTIONFS_RNDIS
  24 #    define USB_ETH_RNDIS y
  25 #  endif
  26
  27 #  include "u_ecm.h"
  28 #  include "u_gether.h"
  29 #  ifdef USB_ETH_RNDIS
  30 #    include "u_rndis.h"
  31 #    include "rndis.h"
  32 #  endif
  33 #  include "u_ether.h"
  34
  35 USB_ETHERNET_MODULE_PARAMETERS();
  36
  37 #  ifdef CONFIG_USB_FUNCTIONFS_ETH
  38 static int eth_bind_config(struct usb_configuration *c);
  39 static struct usb_function_instance *fi_ecm;
  40 static struct usb_function *f_ecm;
  41 static struct usb_function_instance *fi_geth;
  42 static struct usb_function *f_geth;
  43 #  endif
  44 #  ifdef CONFIG_USB_FUNCTIONFS_RNDIS
  45 static int bind_rndis_config(struct usb_configuration *c);
  46 static struct usb_function_instance *fi_rndis;
  47 static struct usb_function *f_rndis;
  48 #  endif
  49 #endif
  50
  51 #include "u_fs.h"
  52
  53 #define DRIVER_NAME     "g_ffs"
  54 #define DRIVER_DESC     "USB Function Filesystem"
  55 #define DRIVER_VERSION  "24 Aug 2004"
  56
  57 MODULE_DESCRIPTION(DRIVER_DESC);
  58 MODULE_AUTHOR("Michal Nazarewicz");
  59 MODULE_LICENSE("GPL");
  60
  61 #define GFS_VENDOR_ID   0x1d6b  /* Linux Foundation */
  62 #define GFS_PRODUCT_ID  0x0105  /* FunctionFS Gadget */
  63
  64 #define GFS_MAX_DEVS    10
  65
  66 USB_GADGET_COMPOSITE_OPTIONS();
  67
  68 static struct usb_device_descriptor gfs_dev_desc = {
  69         .bLength                = sizeof gfs_dev_desc,
  70         .bDescriptorType        = USB_DT_DEVICE,
  71
  72         /* .bcdUSB = DYNAMIC */
  73         .bDeviceClass           = USB_CLASS_PER_INTERFACE,
  74
  75         .idVendor               = cpu_to_le16(GFS_VENDOR_ID),
  76         .idProduct              = cpu_to_le16(GFS_PRODUCT_ID),
  77 };
  78
  79 static char *func_names[GFS_MAX_DEVS];
  80 static unsigned int func_num;
  81
  82 module_param_named(bDeviceClass,    gfs_dev_desc.bDeviceClass,    byte,   0644);
  83 MODULE_PARM_DESC(bDeviceClass, "USB Device class");
  84 module_param_named(bDeviceSubClass, gfs_dev_desc.bDeviceSubClass, byte,   0644);
  85 MODULE_PARM_DESC(bDeviceSubClass, "USB Device subclass");
  86 module_param_named(bDeviceProtocol, gfs_dev_desc.bDeviceProtocol, byte,   0644);
  87 MODULE_PARM_DESC(bDeviceProtocol, "USB Device protocol");
  88 module_param_array_named(functions, func_names, charp, &func_num, 0);
  89 MODULE_PARM_DESC(functions, "USB Functions list");
  90
  91 static const struct usb_descriptor_header *gfs_otg_desc[2];
  92
  93 /* String IDs are assigned dynamically */
  94 static struct usb_string gfs_strings[] = {
  95         [USB_GADGET_MANUFACTURER_IDX].s = "",
  96         [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
  97         [USB_GADGET_SERIAL_IDX].s = "",
  98 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
  99         { .s = "FunctionFS + RNDIS" },
 100 #endif
 101 #ifdef CONFIG_USB_FUNCTIONFS_ETH
 102         { .s = "FunctionFS + ECM" },
 103 #endif
 104 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
 105         { .s = "FunctionFS" },
 106 #endif
 107         {  } /* end of list */
 108 };
 109
 110 static struct usb_gadget_strings *gfs_dev_strings[] = {
 111         &(struct usb_gadget_strings) {
 112                 .language       = 0x0409,       /* en-us */
 113                 .strings        = gfs_strings,
 114         },
 115         NULL,
 116 };
 117
 118 struct gfs_configuration {
 119         struct usb_configuration c;
 120         int (*eth)(struct usb_configuration *c);
 121         int num;
 122 };
 123
 124 static struct gfs_configuration gfs_configurations[] = {
 125 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
 126         {
 127                 .eth            = bind_rndis_config,
 128         },
 129 #endif
 130
 131 #ifdef CONFIG_USB_FUNCTIONFS_ETH
 132         {
 133                 .eth            = eth_bind_config,
 134         },
 135 #endif
 136
 137 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
 138         {
 139         },
 140 #endif
 141 };
 142
 143 static void *functionfs_acquire_dev(struct ffs_dev *dev);
 144 static void functionfs_release_dev(struct ffs_dev *dev);
 145 static int functionfs_ready_callback(struct ffs_data *ffs);
 146 static void functionfs_closed_callback(struct ffs_data *ffs);
 147 static int gfs_bind(struct usb_composite_dev *cdev);
 148 static int gfs_unbind(struct usb_composite_dev *cdev);
 149 static int gfs_do_config(struct usb_configuration *c);
 150
 151
 152 static struct usb_composite_driver gfs_driver = {
 153         .name           = DRIVER_NAME,
 154         .dev            = &gfs_dev_desc,
 155         .strings        = gfs_dev_strings,
 156         .max_speed      = USB_SPEED_HIGH,
 157         .bind           = gfs_bind,
 158         .unbind         = gfs_unbind,
 159 };
 160
 161 static unsigned int missing_funcs;
 162 static bool gfs_registered;
 163 static bool gfs_single_func;
 164 static struct usb_function_instance **fi_ffs;
 165 static struct usb_function **f_ffs[] = {
 166 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
 167         NULL,
 168 #endif
 169
 170 #ifdef CONFIG_USB_FUNCTIONFS_ETH
 171         NULL,
 172 #endif
 173
 174 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
 175         NULL,
 176 #endif
 177 };
 178
 179 #define N_CONF ARRAY_SIZE(f_ffs)
 180
 181 static int __init gfs_init(void)
 182 {
 183         struct f_fs_opts *opts;
 184         int i;
 185         int ret = 0;
 186
 187         ENTER();
 188
 189         if (func_num < 2) {
 190                 gfs_single_func = true;
 191                 func_num = 1;
 192         }
 193
 194         /*
 195          * Allocate in one chunk for easier maintenance
 196          */
 197         f_ffs[0] = kcalloc(func_num * N_CONF, sizeof(*f_ffs), GFP_KERNEL);
 198         if (!f_ffs[0]) {
 199                 ret = -ENOMEM;
 200                 goto no_func;
 201         }
 202         for (i = 1; i < N_CONF; ++i)
 203                 f_ffs[i] = f_ffs[0] + i * func_num;
 204
 205         fi_ffs = kcalloc(func_num, sizeof(*fi_ffs), GFP_KERNEL);
 206         if (!fi_ffs) {
 207                 ret = -ENOMEM;
 208                 goto no_func;
 209         }
 210
 211         for (i = 0; i < func_num; i++) {
 212                 fi_ffs[i] = usb_get_function_instance("ffs");
 213                 if (IS_ERR(fi_ffs[i])) {
 214                         ret = PTR_ERR(fi_ffs[i]);
 215                         --i;
 216                         goto no_dev;
 217                 }
 218                 opts = to_f_fs_opts(fi_ffs[i]);
 219                 if (gfs_single_func)
 220                         ret = ffs_single_dev(opts->dev);
 221                 else
 222                         ret = ffs_name_dev(opts->dev, func_names[i]);
 223                 if (ret)
 224                         goto no_dev;
 225                 opts->dev->ffs_ready_callback = functionfs_ready_callback;
 226                 opts->dev->ffs_closed_callback = functionfs_closed_callback;
 227                 opts->dev->ffs_acquire_dev_callback = functionfs_acquire_dev;
 228                 opts->dev->ffs_release_dev_callback = functionfs_release_dev;
 229                 opts->no_configfs = true;
 230         }
 231
 232         missing_funcs = func_num;
 233
 234         return 0;
 235 no_dev:
 236         while (i >= 0)
 237                 usb_put_function_instance(fi_ffs[i--]);
 238         kfree(fi_ffs);
 239 no_func:
 240         kfree(f_ffs[0]);
 241         return ret;
 242 }
 243 module_init(gfs_init);
 244
 245 static void __exit gfs_exit(void)
 246 {
 247         int i;
 248
 249         ENTER();
 250
 251         if (gfs_registered)
 252                 usb_composite_unregister(&gfs_driver);
 253         gfs_registered = false;
 254
 255         kfree(f_ffs[0]);
 256
 257         for (i = 0; i < func_num; i++)
 258                 usb_put_function_instance(fi_ffs[i]);
 259
 260         kfree(fi_ffs);
 261 }
 262 module_exit(gfs_exit);
 263
 264 static void *functionfs_acquire_dev(struct ffs_dev *dev)
 265 {
 266         if (!try_module_get(THIS_MODULE))
 267                 return ERR_PTR(-ENOENT);
 268
 269         return NULL;
 270 }
 271
 272 static void functionfs_release_dev(struct ffs_dev *dev)
 273 {
 274         module_put(THIS_MODULE);
 275 }
 276
 277 /*
 278  * The caller of this function takes ffs_lock
 279  */
 280 static int functionfs_ready_callback(struct ffs_data *ffs)
 281 {
 282         int ret = 0;
 283
 284         if (--missing_funcs)
 285                 return 0;
 286
 287         if (gfs_registered)
 288                 return -EBUSY;
 289
 290         gfs_registered = true;
 291
 292         ret = usb_composite_probe(&gfs_driver);
 293         if (unlikely(ret < 0)) {
 294                 ++missing_funcs;
 295                 gfs_registered = false;
 296         }
 297
 298         return ret;
 299 }
 300
 301 /*
 302  * The caller of this function takes ffs_lock
 303  */
 304 static void functionfs_closed_callback(struct ffs_data *ffs)
 305 {
 306         missing_funcs++;
 307
 308         if (gfs_registered)
 309                 usb_composite_unregister(&gfs_driver);
 310         gfs_registered = false;
 311 }
 312
 313 /*
 314  * It is assumed that gfs_bind is called from a context where ffs_lock is held
 315  */
 316 static int gfs_bind(struct usb_composite_dev *cdev)
 317 {
 318 #if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
 319         struct net_device *net;
 320 #endif
 321         int ret, i;
 322
 323         ENTER();
 324
 325         if (missing_funcs)
 326                 return -ENODEV;
 327 #if defined CONFIG_USB_FUNCTIONFS_ETH
 328         if (can_support_ecm(cdev->gadget)) {
 329                 struct f_ecm_opts *ecm_opts;
 330
 331                 fi_ecm = usb_get_function_instance("ecm");
 332                 if (IS_ERR(fi_ecm))
 333                         return PTR_ERR(fi_ecm);
 334                 ecm_opts = container_of(fi_ecm, struct f_ecm_opts, func_inst);
 335                 net = ecm_opts->net;
 336         } else {
 337                 struct f_gether_opts *geth_opts;
 338
 339                 fi_geth = usb_get_function_instance("geth");
 340                 if (IS_ERR(fi_geth))
 341                         return PTR_ERR(fi_geth);
 342                 geth_opts = container_of(fi_geth, struct f_gether_opts,
 343                                          func_inst);
 344                 net = geth_opts->net;
 345         }
 346 #endif
 347
 348 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
 349         {
 350                 fi_rndis = usb_get_function_instance("rndis");
 351                 if (IS_ERR(fi_rndis)) {
 352                         ret = PTR_ERR(fi_rndis);
 353                         goto error;
 354                 }
 355 #ifndef CONFIG_USB_FUNCTIONFS_ETH
 356                 net = container_of(fi_rndis, struct f_rndis_opts,
 357                                    func_inst)->net;
 358 #endif
 359         }
 360 #endif
 361
 362 #if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
 363         gether_set_qmult(net, qmult);
 364         if (!gether_set_host_addr(net, host_addr))
 365                 pr_info("using host ethernet address: %s", host_addr);
 366         if (!gether_set_dev_addr(net, dev_addr))
 367                 pr_info("using self ethernet address: %s", dev_addr);
 368 #endif
 369
 370 #if defined CONFIG_USB_FUNCTIONFS_RNDIS && defined CONFIG_USB_FUNCTIONFS_ETH
 371         gether_set_gadget(net, cdev->gadget);
 372         ret = gether_register_netdev(net);
 373         if (ret)
 374                 goto error_rndis;
 375
 376         if (can_support_ecm(cdev->gadget)) {
 377                 struct f_ecm_opts *ecm_opts;
 378
 379                 ecm_opts = container_of(fi_ecm, struct f_ecm_opts, func_inst);
 380                 ecm_opts->bound = true;
 381         } else {
 382                 struct f_gether_opts *geth_opts;
 383
 384                 geth_opts = container_of(fi_geth, struct f_gether_opts,
 385                                          func_inst);
 386                 geth_opts->bound = true;
 387         }
 388
 389         rndis_borrow_net(fi_rndis, net);
 390 #endif
 391
 392         /* TODO: gstrings_attach? */
 393         ret = usb_string_ids_tab(cdev, gfs_strings);
 394         if (unlikely(ret < 0))
 395                 goto error_rndis;
 396         gfs_dev_desc.iProduct = gfs_strings[USB_GADGET_PRODUCT_IDX].id;
 397
 398         if (gadget_is_otg(cdev->gadget) && !gfs_otg_desc[0]) {
 399                 struct usb_descriptor_header *usb_desc;
 400
 401                 usb_desc = usb_otg_descriptor_alloc(cdev->gadget);
 402                 if (!usb_desc)
 403                         goto error_rndis;
 404                 usb_otg_descriptor_init(cdev->gadget, usb_desc);
 405                 gfs_otg_desc[0] = usb_desc;
 406                 gfs_otg_desc[1] = NULL;
 407         }
 408
 409         for (i = 0; i < ARRAY_SIZE(gfs_configurations); ++i) {
 410                 struct gfs_configuration *c = gfs_configurations + i;
 411                 int sid = USB_GADGET_FIRST_AVAIL_IDX + i;
 412
 413                 c->c.label                      = gfs_strings[sid].s;
 414                 c->c.iConfiguration             = gfs_strings[sid].id;
 415                 c->c.bConfigurationValue        = 1 + i;
 416                 c->c.bmAttributes               = USB_CONFIG_ATT_SELFPOWER;
 417
 418                 c->num = i;
 419
 420                 ret = usb_add_config(cdev, &c->c, gfs_do_config);
 421                 if (unlikely(ret < 0))
 422                         goto error_unbind;
 423         }
 424         usb_composite_overwrite_options(cdev, &coverwrite);
 425         return 0;
 426
 427 /* TODO */
 428 error_unbind:
 429         kfree(gfs_otg_desc[0]);
 430         gfs_otg_desc[0] = NULL;
 431 error_rndis:
 432 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
 433         usb_put_function_instance(fi_rndis);
 434 error:
 435 #endif
 436 #if defined CONFIG_USB_FUNCTIONFS_ETH
 437         if (can_support_ecm(cdev->gadget))
 438                 usb_put_function_instance(fi_ecm);
 439         else
 440                 usb_put_function_instance(fi_geth);
 441 #endif
 442         return ret;
 443 }
 444
 445 /*
 446  * It is assumed that gfs_unbind is called from a context where ffs_lock is held
 447  */
 448 static int gfs_unbind(struct usb_composite_dev *cdev)
 449 {
 450         int i;
 451
 452         ENTER();
 453
 454
 455 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
 456         usb_put_function(f_rndis);
 457         usb_put_function_instance(fi_rndis);
 458 #endif
 459
 460 #if defined CONFIG_USB_FUNCTIONFS_ETH
 461         if (can_support_ecm(cdev->gadget)) {
 462                 usb_put_function(f_ecm);
 463                 usb_put_function_instance(fi_ecm);
 464         } else {
 465                 usb_put_function(f_geth);
 466                 usb_put_function_instance(fi_geth);
 467         }
 468 #endif
 469         for (i = 0; i < N_CONF * func_num; ++i)
 470                 usb_put_function(*(f_ffs[0] + i));
 471
 472         kfree(gfs_otg_desc[0]);
 473         gfs_otg_desc[0] = NULL;
 474
 475         return 0;
 476 }
 477
 478 /*
 479  * It is assumed that gfs_do_config is called from a context where
 480  * ffs_lock is held
 481  */
 482 static int gfs_do_config(struct usb_configuration *c)
 483 {
 484         struct gfs_configuration *gc =
 485                 container_of(c, struct gfs_configuration, c);
 486         int i;
 487         int ret;
 488
 489         if (missing_funcs)
 490                 return -ENODEV;
 491
 492         if (gadget_is_otg(c->cdev->gadget)) {
 493                 c->descriptors = gfs_otg_desc;
 494                 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 495         }
 496
 497         if (gc->eth) {
 498                 ret = gc->eth(c);
 499                 if (unlikely(ret < 0))
 500                         return ret;
 501         }
 502
 503         for (i = 0; i < func_num; i++) {
 504                 f_ffs[gc->num][i] = usb_get_function(fi_ffs[i]);
 505                 if (IS_ERR(f_ffs[gc->num][i])) {
 506                         ret = PTR_ERR(f_ffs[gc->num][i]);
 507                         goto error;
 508                 }
 509                 ret = usb_add_function(c, f_ffs[gc->num][i]);
 510                 if (ret < 0) {
 511                         usb_put_function(f_ffs[gc->num][i]);
 512                         goto error;
 513                 }
 514         }
 515
 516         /*
 517          * After previous do_configs there may be some invalid
 518          * pointers in c->interface array.  This happens every time
 519          * a user space function with fewer interfaces than a user
 520          * space function that was run before the new one is run.  The
 521          * compasit's set_config() assumes that if there is no more
 522          * then MAX_CONFIG_INTERFACES interfaces in a configuration
 523          * then there is a NULL pointer after the last interface in
 524          * c->interface array.  We need to make sure this is true.
 525          */
 526         if (c->next_interface_id < ARRAY_SIZE(c->interface))
 527                 c->interface[c->next_interface_id] = NULL;
 528
 529         return 0;
 530 error:
 531         while (--i >= 0) {
 532                 if (!IS_ERR(f_ffs[gc->num][i]))
 533                         usb_remove_function(c, f_ffs[gc->num][i]);
 534                 usb_put_function(f_ffs[gc->num][i]);
 535         }
 536         return ret;
 537 }
 538
 539 #ifdef CONFIG_USB_FUNCTIONFS_ETH
 540
 541 static int eth_bind_config(struct usb_configuration *c)
 542 {
 543         int status = 0;
 544
 545         if (can_support_ecm(c->cdev->gadget)) {
 546                 f_ecm = usb_get_function(fi_ecm);
 547                 if (IS_ERR(f_ecm))
 548                         return PTR_ERR(f_ecm);
 549
 550                 status = usb_add_function(c, f_ecm);
 551                 if (status < 0)
 552                         usb_put_function(f_ecm);
 553
 554         } else {
 555                 f_geth = usb_get_function(fi_geth);
 556                 if (IS_ERR(f_geth))
 557                         return PTR_ERR(f_geth);
 558
 559                 status = usb_add_function(c, f_geth);
 560                 if (status < 0)
 561                         usb_put_function(f_geth);
 562         }
 563         return status;
 564 }
 565
 566 #endif
 567
 568 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
 569
 570 static int bind_rndis_config(struct usb_configuration *c)
 571 {
 572         int status = 0;
 573
 574         f_rndis = usb_get_function(fi_rndis);
 575         if (IS_ERR(f_rndis))
 576                 return PTR_ERR(f_rndis);
 577
 578         status = usb_add_function(c, f_rndis);
 579         if (status < 0)
 580                 usb_put_function(f_rndis);
 581
 582         return status;
 583 }
 584
 585 #endif