drivers/usb/gadget/ncm.c

   1 /*
   2  * ncm.c -- NCM gadget driver
   3  *
   4  * Copyright (C) 2010 Nokia Corporation
   5  * Contact: Yauheni Kaliuta <yauheni.kaliuta@nokia.com>
   6  *
   7  * The driver borrows from ether.c which is:
   8  *
   9  * Copyright (C) 2003-2005,2008 David Brownell
  10  * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
  11  * Copyright (C) 2008 Nokia Corporation
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  26  */
  27
  28 /* #define DEBUG */
  29 /* #define VERBOSE_DEBUG */
  30
  31 #include <linux/kernel.h>
  32 #include <linux/utsname.h>
  33
  34
  35 #include "u_ether.h"
  36
  37 #define DRIVER_DESC             "NCM Gadget"
  38
  39 /*-------------------------------------------------------------------------*/
  40
  41 /*
  42  * Kbuild is not very cooperative with respect to linking separately
  43  * compiled library objects into one module.  So for now we won't use
  44  * separate compilation ... ensuring init/exit sections work to shrink
  45  * the runtime footprint, and giving us at least some parts of what
  46  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
  47  */
  48 #include "composite.c"
  49 #include "usbstring.c"
  50 #include "config.c"
  51 #include "epautoconf.c"
  52
  53 #include "f_ncm.c"
  54 #include "u_ether.c"
  55
  56 /*-------------------------------------------------------------------------*/
  57
  58 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  59  * Instead:  allocate your own, using normal USB-IF procedures.
  60  */
  61
  62 /* Thanks to NetChip Technologies for donating this product ID.
  63  * It's for devices with only CDC Ethernet configurations.
  64  */
  65 #define CDC_VENDOR_NUM          0x0525  /* NetChip */
  66 #define CDC_PRODUCT_NUM         0xa4a1  /* Linux-USB Ethernet Gadget */
  67
  68 /*-------------------------------------------------------------------------*/
  69
  70 static struct usb_device_descriptor device_desc = {
  71         .bLength =              sizeof device_desc,
  72         .bDescriptorType =      USB_DT_DEVICE,
  73
  74         .bcdUSB =               cpu_to_le16 (0x0200),
  75
  76         .bDeviceClass =         USB_CLASS_COMM,
  77         .bDeviceSubClass =      0,
  78         .bDeviceProtocol =      0,
  79         /* .bMaxPacketSize0 = f(hardware) */
  80
  81         /* Vendor and product id defaults change according to what configs
  82          * we support.  (As does bNumConfigurations.)  These values can
  83          * also be overridden by module parameters.
  84          */
  85         .idVendor =             cpu_to_le16 (CDC_VENDOR_NUM),
  86         .idProduct =            cpu_to_le16 (CDC_PRODUCT_NUM),
  87         /* .bcdDevice = f(hardware) */
  88         /* .iManufacturer = DYNAMIC */
  89         /* .iProduct = DYNAMIC */
  90         /* NO SERIAL NUMBER */
  91         .bNumConfigurations =   1,
  92 };
  93
  94 static struct usb_otg_descriptor otg_descriptor = {
  95         .bLength =              sizeof otg_descriptor,
  96         .bDescriptorType =      USB_DT_OTG,
  97
  98         /* REVISIT SRP-only hardware is possible, although
  99          * it would not be called "OTG" ...
 100          */
 101         .bmAttributes =         USB_OTG_SRP | USB_OTG_HNP,
 102 };
 103
 104 static const struct usb_descriptor_header *otg_desc[] = {
 105         (struct usb_descriptor_header *) &otg_descriptor,
 106         NULL,
 107 };
 108
 109
 110 /* string IDs are assigned dynamically */
 111
 112 #define STRING_MANUFACTURER_IDX         0
 113 #define STRING_PRODUCT_IDX              1
 114
 115 static char manufacturer[50];
 116
 117 static struct usb_string strings_dev[] = {
 118         [STRING_MANUFACTURER_IDX].s = manufacturer,
 119         [STRING_PRODUCT_IDX].s = DRIVER_DESC,
 120         {  } /* end of list */
 121 };
 122
 123 static struct usb_gadget_strings stringtab_dev = {
 124         .language       = 0x0409,       /* en-us */
 125         .strings        = strings_dev,
 126 };
 127
 128 static struct usb_gadget_strings *dev_strings[] = {
 129         &stringtab_dev,
 130         NULL,
 131 };
 132
 133 static u8 hostaddr[ETH_ALEN];
 134
 135 /*-------------------------------------------------------------------------*/
 136
 137 static int __init ncm_do_config(struct usb_configuration *c)
 138 {
 139         /* FIXME alloc iConfiguration string, set it in c->strings */
 140
 141         if (gadget_is_otg(c->cdev->gadget)) {
 142                 c->descriptors = otg_desc;
 143                 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 144         }
 145
 146         return ncm_bind_config(c, hostaddr);
 147 }
 148
 149 static struct usb_configuration ncm_config_driver = {
 150         /* .label = f(hardware) */
 151         .label                  = "CDC Ethernet (NCM)",
 152         .bConfigurationValue    = 1,
 153         /* .iConfiguration = DYNAMIC */
 154         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
 155 };
 156
 157 /*-------------------------------------------------------------------------*/
 158
 159 static int __init gncm_bind(struct usb_composite_dev *cdev)
 160 {
 161         int                     gcnum;
 162         struct usb_gadget       *gadget = cdev->gadget;
 163         int                     status;
 164
 165         /* set up network link layer */
 166         status = gether_setup(cdev->gadget, hostaddr);
 167         if (status < 0)
 168                 return status;
 169
 170         gcnum = usb_gadget_controller_number(gadget);
 171         if (gcnum >= 0)
 172                 device_desc.bcdDevice = cpu_to_le16(0x0300 | gcnum);
 173         else {
 174                 /* We assume that can_support_ecm() tells the truth;
 175                  * but if the controller isn't recognized at all then
 176                  * that assumption is a bit more likely to be wrong.
 177                  */
 178                 dev_warn(&gadget->dev,
 179                          "controller '%s' not recognized; trying %s\n",
 180                          gadget->name,
 181                          ncm_config_driver.label);
 182                 device_desc.bcdDevice =
 183                         cpu_to_le16(0x0300 | 0x0099);
 184         }
 185
 186
 187         /* Allocate string descriptor numbers ... note that string
 188          * contents can be overridden by the composite_dev glue.
 189          */
 190
 191         /* device descriptor strings: manufacturer, product */
 192         snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
 193                 init_utsname()->sysname, init_utsname()->release,
 194                 gadget->name);
 195         status = usb_string_id(cdev);
 196         if (status < 0)
 197                 goto fail;
 198         strings_dev[STRING_MANUFACTURER_IDX].id = status;
 199         device_desc.iManufacturer = status;
 200
 201         status = usb_string_id(cdev);
 202         if (status < 0)
 203                 goto fail;
 204         strings_dev[STRING_PRODUCT_IDX].id = status;
 205         device_desc.iProduct = status;
 206
 207         status = usb_add_config(cdev, &ncm_config_driver,
 208                                 ncm_do_config);
 209         if (status < 0)
 210                 goto fail;
 211
 212         dev_info(&gadget->dev, "%s\n", DRIVER_DESC);
 213
 214         return 0;
 215
 216 fail:
 217         gether_cleanup();
 218         return status;
 219 }
 220
 221 static int __exit gncm_unbind(struct usb_composite_dev *cdev)
 222 {
 223         gether_cleanup();
 224         return 0;
 225 }
 226
 227 static struct usb_composite_driver ncm_driver = {
 228         .name           = "g_ncm",
 229         .dev            = &device_desc,
 230         .strings        = dev_strings,
 231         .unbind         = __exit_p(gncm_unbind),
 232 };
 233
 234 MODULE_DESCRIPTION(DRIVER_DESC);
 235 MODULE_AUTHOR("Yauheni Kaliuta");
 236 MODULE_LICENSE("GPL");
 237
 238 static int __init init(void)
 239 {
 240         return usb_composite_probe(&ncm_driver, gncm_bind);
 241 }
 242 module_init(init);
 243
 244 static void __exit cleanup(void)
 245 {
 246         usb_composite_unregister(&ncm_driver);
 247 }
 248 module_exit(cleanup);