drivers/usb/gadget/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 <m.nazarewicz@samsung.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  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/utsname.h>
  24
  25 /*
  26  * kbuild is not very cooperative with respect to linking separately
  27  * compiled library objects into one module.  So for now we won't use
  28  * separate compilation ... ensuring init/exit sections work to shrink
  29  * the runtime footprint, and giving us at least some parts of what
  30  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
  31  */
  32
  33 #include "composite.c"
  34 #include "usbstring.c"
  35 #include "config.c"
  36 #include "epautoconf.c"
  37
  38 #if defined CONFIG_USB_FUNCTIONFS_ETH || defined CONFIG_USB_FUNCTIONFS_RNDIS
  39 #  if defined USB_ETH_RNDIS
  40 #    undef USB_ETH_RNDIS
  41 #  endif
  42 #  ifdef CONFIG_USB_FUNCTIONFS_RNDIS
  43 #    define USB_ETH_RNDIS y
  44 #  endif
  45
  46 #  include "f_ecm.c"
  47 #  include "f_subset.c"
  48 #  ifdef USB_ETH_RNDIS
  49 #    include "f_rndis.c"
  50 #    include "rndis.c"
  51 #  endif
  52 #  include "u_ether.c"
  53
  54 static u8 gfs_hostaddr[ETH_ALEN];
  55 #  ifdef CONFIG_USB_FUNCTIONFS_ETH
  56 static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
  57 #  endif
  58 #else
  59 #  define gether_cleanup() do { } while (0)
  60 #  define gether_setup(gadget, hostaddr)   ((int)0)
  61 #  define gfs_hostaddr NULL
  62 #endif
  63
  64 #include "f_fs.c"
  65
  66 #define DRIVER_NAME     "g_ffs"
  67 #define DRIVER_DESC     "USB Function Filesystem"
  68 #define DRIVER_VERSION  "24 Aug 2004"
  69
  70 MODULE_DESCRIPTION(DRIVER_DESC);
  71 MODULE_AUTHOR("Michal Nazarewicz");
  72 MODULE_LICENSE("GPL");
  73
  74 #define GFS_VENDOR_ID   0x1d6b  /* Linux Foundation */
  75 #define GFS_PRODUCT_ID  0x0105  /* FunctionFS Gadget */
  76
  77 static struct usb_device_descriptor gfs_dev_desc = {
  78         .bLength                = sizeof gfs_dev_desc,
  79         .bDescriptorType        = USB_DT_DEVICE,
  80
  81         .bcdUSB                 = cpu_to_le16(0x0200),
  82         .bDeviceClass           = USB_CLASS_PER_INTERFACE,
  83
  84         .idVendor               = cpu_to_le16(GFS_VENDOR_ID),
  85         .idProduct              = cpu_to_le16(GFS_PRODUCT_ID),
  86 };
  87
  88 module_param_named(bDeviceClass,    gfs_dev_desc.bDeviceClass,    byte,   0644);
  89 MODULE_PARM_DESC(bDeviceClass, "USB Device class");
  90 module_param_named(bDeviceSubClass, gfs_dev_desc.bDeviceSubClass, byte,   0644);
  91 MODULE_PARM_DESC(bDeviceSubClass, "USB Device subclass");
  92 module_param_named(bDeviceProtocol, gfs_dev_desc.bDeviceProtocol, byte,   0644);
  93 MODULE_PARM_DESC(bDeviceProtocol, "USB Device protocol");
  94
  95 static const struct usb_descriptor_header *gfs_otg_desc[] = {
  96         (const struct usb_descriptor_header *)
  97         &(const struct usb_otg_descriptor) {
  98                 .bLength                = sizeof(struct usb_otg_descriptor),
  99                 .bDescriptorType        = USB_DT_OTG,
 100
 101                 /*
 102                  * REVISIT SRP-only hardware is possible, although
 103                  * it would not be called "OTG" ...
 104                  */
 105                 .bmAttributes           = USB_OTG_SRP | USB_OTG_HNP,
 106         },
 107
 108         NULL
 109 };
 110
 111 /* String IDs are assigned dynamically */
 112 static struct usb_string gfs_strings[] = {
 113 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
 114         { .s = "FunctionFS + RNDIS" },
 115 #endif
 116 #ifdef CONFIG_USB_FUNCTIONFS_ETH
 117         { .s = "FunctionFS + ECM" },
 118 #endif
 119 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
 120         { .s = "FunctionFS" },
 121 #endif
 122         {  } /* end of list */
 123 };
 124
 125 static struct usb_gadget_strings *gfs_dev_strings[] = {
 126         &(struct usb_gadget_strings) {
 127                 .language       = 0x0409,       /* en-us */
 128                 .strings        = gfs_strings,
 129         },
 130         NULL,
 131 };
 132
 133 struct gfs_configuration {
 134         struct usb_configuration c;
 135         int (*eth)(struct usb_configuration *c, u8 *ethaddr);
 136 } gfs_configurations[] = {
 137 #ifdef CONFIG_USB_FUNCTIONFS_RNDIS
 138         {
 139                 .eth            = rndis_bind_config,
 140         },
 141 #endif
 142
 143 #ifdef CONFIG_USB_FUNCTIONFS_ETH
 144         {
 145                 .eth            = eth_bind_config,
 146         },
 147 #endif
 148
 149 #ifdef CONFIG_USB_FUNCTIONFS_GENERIC
 150         {
 151         },
 152 #endif
 153 };
 154
 155 static int gfs_bind(struct usb_composite_dev *cdev);
 156 static int gfs_unbind(struct usb_composite_dev *cdev);
 157 static int gfs_do_config(struct usb_configuration *c);
 158
 159 static struct usb_composite_driver gfs_driver = {
 160         .name           = DRIVER_NAME,
 161         .dev            = &gfs_dev_desc,
 162         .strings        = gfs_dev_strings,
 163         .unbind         = gfs_unbind,
 164         .iProduct       = DRIVER_DESC,
 165 };
 166
 167 static struct ffs_data *gfs_ffs_data;
 168 static unsigned long gfs_registered;
 169
 170 static int  gfs_init(void)
 171 {
 172         ENTER();
 173
 174         return functionfs_init();
 175 }
 176 module_init(gfs_init);
 177
 178 static void  gfs_exit(void)
 179 {
 180         ENTER();
 181
 182         if (test_and_clear_bit(0, &gfs_registered))
 183                 usb_composite_unregister(&gfs_driver);
 184
 185         functionfs_cleanup();
 186 }
 187 module_exit(gfs_exit);
 188
 189 static int functionfs_ready_callback(struct ffs_data *ffs)
 190 {
 191         int ret;
 192
 193         ENTER();
 194
 195         if (WARN_ON(test_and_set_bit(0, &gfs_registered)))
 196                 return -EBUSY;
 197
 198         gfs_ffs_data = ffs;
 199         ret = usb_composite_probe(&gfs_driver, gfs_bind);
 200         if (unlikely(ret < 0))
 201                 clear_bit(0, &gfs_registered);
 202         return ret;
 203 }
 204
 205 static void functionfs_closed_callback(struct ffs_data *ffs)
 206 {
 207         ENTER();
 208
 209         if (test_and_clear_bit(0, &gfs_registered))
 210                 usb_composite_unregister(&gfs_driver);
 211 }
 212
 213 static int functionfs_check_dev_callback(const char *dev_name)
 214 {
 215         return 0;
 216 }
 217
 218 static int gfs_bind(struct usb_composite_dev *cdev)
 219 {
 220         int ret, i;
 221
 222         ENTER();
 223
 224         if (WARN_ON(!gfs_ffs_data))
 225                 return -ENODEV;
 226
 227         ret = gether_setup(cdev->gadget, gfs_hostaddr);
 228         if (unlikely(ret < 0))
 229                 goto error_quick;
 230
 231         ret = usb_string_ids_tab(cdev, gfs_strings);
 232         if (unlikely(ret < 0))
 233                 goto error;
 234
 235         ret = functionfs_bind(gfs_ffs_data, cdev);
 236         if (unlikely(ret < 0))
 237                 goto error;
 238
 239         for (i = 0; i < ARRAY_SIZE(gfs_configurations); ++i) {
 240                 struct gfs_configuration *c = gfs_configurations + i;
 241
 242                 c->c.label                      = gfs_strings[i].s;
 243                 c->c.iConfiguration             = gfs_strings[i].id;
 244                 c->c.bConfigurationValue        = 1 + i;
 245                 c->c.bmAttributes               = USB_CONFIG_ATT_SELFPOWER;
 246
 247                 ret = usb_add_config(cdev, &c->c, gfs_do_config);
 248                 if (unlikely(ret < 0))
 249                         goto error_unbind;
 250         }
 251
 252         return 0;
 253
 254 error_unbind:
 255         functionfs_unbind(gfs_ffs_data);
 256 error:
 257         gether_cleanup();
 258 error_quick:
 259         gfs_ffs_data = NULL;
 260         return ret;
 261 }
 262
 263 static int gfs_unbind(struct usb_composite_dev *cdev)
 264 {
 265         ENTER();
 266
 267         /*
 268          * We may have been called in an error recovery from
 269          * composite_bind() after gfs_unbind() failure so we need to
 270          * check if gfs_ffs_data is not NULL since gfs_bind() handles
 271          * all error recovery itself.  I'd rather we werent called
 272          * from composite on orror recovery, but what you're gonna
 273          * do...?
 274          */
 275         if (gfs_ffs_data) {
 276                 gether_cleanup();
 277                 functionfs_unbind(gfs_ffs_data);
 278                 gfs_ffs_data = NULL;
 279         }
 280
 281         return 0;
 282 }
 283
 284 static int gfs_do_config(struct usb_configuration *c)
 285 {
 286         struct gfs_configuration *gc =
 287                 container_of(c, struct gfs_configuration, c);
 288         int ret;
 289
 290         if (WARN_ON(!gfs_ffs_data))
 291                 return -ENODEV;
 292
 293         if (gadget_is_otg(c->cdev->gadget)) {
 294                 c->descriptors = gfs_otg_desc;
 295                 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 296         }
 297
 298         if (gc->eth) {
 299                 ret = gc->eth(c, gfs_hostaddr);
 300                 if (unlikely(ret < 0))
 301                         return ret;
 302         }
 303
 304         ret = functionfs_bind_config(c->cdev, c, gfs_ffs_data);
 305         if (unlikely(ret < 0))
 306                 return ret;
 307
 308         /*
 309          * After previous do_configs there may be some invalid
 310          * pointers in c->interface array.  This happens every time
 311          * a user space function with fewer interfaces than a user
 312          * space function that was run before the new one is run.  The
 313          * compasit's set_config() assumes that if there is no more
 314          * then MAX_CONFIG_INTERFACES interfaces in a configuration
 315          * then there is a NULL pointer after the last interface in
 316          * c->interface array.  We need to make sure this is true.
 317          */
 318         if (c->next_interface_id < ARRAY_SIZE(c->interface))
 319                 c->interface[c->next_interface_id] = NULL;
 320
 321         return 0;
 322 }
 323
 324 #ifdef CONFIG_USB_FUNCTIONFS_ETH
 325
 326 static int eth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN])
 327 {
 328         return can_support_ecm(c->cdev->gadget)
 329                 ? ecm_bind_config(c, ethaddr)
 330                 : geth_bind_config(c, ethaddr);
 331 }
 332
 333 #endif