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
  19 /* #define DEBUG */
  20 /* #define VERBOSE_DEBUG */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/usb/composite.h>
  25
  26 #include "u_ether.h"
  27
  28 #define DRIVER_DESC             "NCM Gadget"
  29
  30 /*-------------------------------------------------------------------------*/
  31
  32 /*
  33  * Kbuild is not very cooperative with respect to linking separately
  34  * compiled library objects into one module.  So for now we won't use
  35  * separate compilation ... ensuring init/exit sections work to shrink
  36  * the runtime footprint, and giving us at least some parts of what
  37  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
  38  */
  39 #include "f_ncm.c"
  40
  41 /*-------------------------------------------------------------------------*/
  42
  43 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  44  * Instead:  allocate your own, using normal USB-IF procedures.
  45  */
  46
  47 /* Thanks to NetChip Technologies for donating this product ID.
  48  * It's for devices with only CDC Ethernet configurations.
  49  */
  50 #define CDC_VENDOR_NUM          0x0525  /* NetChip */
  51 #define CDC_PRODUCT_NUM         0xa4a1  /* Linux-USB Ethernet Gadget */
  52
  53 /*-------------------------------------------------------------------------*/
  54 USB_GADGET_COMPOSITE_OPTIONS();
  55
  56 USB_ETHERNET_MODULE_PARAMETERS();
  57
  58 static struct usb_device_descriptor device_desc = {
  59         .bLength =              sizeof device_desc,
  60         .bDescriptorType =      USB_DT_DEVICE,
  61
  62         .bcdUSB =               cpu_to_le16 (0x0200),
  63
  64         .bDeviceClass =         USB_CLASS_COMM,
  65         .bDeviceSubClass =      0,
  66         .bDeviceProtocol =      0,
  67         /* .bMaxPacketSize0 = f(hardware) */
  68
  69         /* Vendor and product id defaults change according to what configs
  70          * we support.  (As does bNumConfigurations.)  These values can
  71          * also be overridden by module parameters.
  72          */
  73         .idVendor =             cpu_to_le16 (CDC_VENDOR_NUM),
  74         .idProduct =            cpu_to_le16 (CDC_PRODUCT_NUM),
  75         /* .bcdDevice = f(hardware) */
  76         /* .iManufacturer = DYNAMIC */
  77         /* .iProduct = DYNAMIC */
  78         /* NO SERIAL NUMBER */
  79         .bNumConfigurations =   1,
  80 };
  81
  82 static struct usb_otg_descriptor otg_descriptor = {
  83         .bLength =              sizeof otg_descriptor,
  84         .bDescriptorType =      USB_DT_OTG,
  85
  86         /* REVISIT SRP-only hardware is possible, although
  87          * it would not be called "OTG" ...
  88          */
  89         .bmAttributes =         USB_OTG_SRP | USB_OTG_HNP,
  90 };
  91
  92 static const struct usb_descriptor_header *otg_desc[] = {
  93         (struct usb_descriptor_header *) &otg_descriptor,
  94         NULL,
  95 };
  96
  97 /* string IDs are assigned dynamically */
  98 static struct usb_string strings_dev[] = {
  99         [USB_GADGET_MANUFACTURER_IDX].s = "",
 100         [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
 101         [USB_GADGET_SERIAL_IDX].s = "",
 102         {  } /* end of list */
 103 };
 104
 105 static struct usb_gadget_strings stringtab_dev = {
 106         .language       = 0x0409,       /* en-us */
 107         .strings        = strings_dev,
 108 };
 109
 110 static struct usb_gadget_strings *dev_strings[] = {
 111         &stringtab_dev,
 112         NULL,
 113 };
 114
 115 struct eth_dev *the_dev;
 116 static u8 host_mac[ETH_ALEN];
 117
 118 /*-------------------------------------------------------------------------*/
 119
 120 static int __init ncm_do_config(struct usb_configuration *c)
 121 {
 122         /* FIXME alloc iConfiguration string, set it in c->strings */
 123
 124         if (gadget_is_otg(c->cdev->gadget)) {
 125                 c->descriptors = otg_desc;
 126                 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 127         }
 128
 129         return ncm_bind_config(c, host_mac, the_dev);
 130 }
 131
 132 static struct usb_configuration ncm_config_driver = {
 133         /* .label = f(hardware) */
 134         .label                  = "CDC Ethernet (NCM)",
 135         .bConfigurationValue    = 1,
 136         /* .iConfiguration = DYNAMIC */
 137         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
 138 };
 139
 140 /*-------------------------------------------------------------------------*/
 141
 142 static int __init gncm_bind(struct usb_composite_dev *cdev)
 143 {
 144         struct usb_gadget       *gadget = cdev->gadget;
 145         int                     status;
 146
 147         /* set up network link layer */
 148         the_dev = gether_setup(cdev->gadget, dev_addr, host_addr, host_mac,
 149                                qmult);
 150         if (IS_ERR(the_dev))
 151                 return PTR_ERR(the_dev);
 152
 153         /* Allocate string descriptor numbers ... note that string
 154          * contents can be overridden by the composite_dev glue.
 155          */
 156
 157         status = usb_string_ids_tab(cdev, strings_dev);
 158         if (status < 0)
 159                 goto fail;
 160         device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 161         device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 162
 163         status = usb_add_config(cdev, &ncm_config_driver,
 164                                 ncm_do_config);
 165         if (status < 0)
 166                 goto fail;
 167
 168         usb_composite_overwrite_options(cdev, &coverwrite);
 169         dev_info(&gadget->dev, "%s\n", DRIVER_DESC);
 170
 171         return 0;
 172
 173 fail:
 174         gether_cleanup(the_dev);
 175         return status;
 176 }
 177
 178 static int __exit gncm_unbind(struct usb_composite_dev *cdev)
 179 {
 180         gether_cleanup(the_dev);
 181         return 0;
 182 }
 183
 184 static __refdata struct usb_composite_driver ncm_driver = {
 185         .name           = "g_ncm",
 186         .dev            = &device_desc,
 187         .strings        = dev_strings,
 188         .max_speed      = USB_SPEED_HIGH,
 189         .bind           = gncm_bind,
 190         .unbind         = __exit_p(gncm_unbind),
 191 };
 192
 193 MODULE_DESCRIPTION(DRIVER_DESC);
 194 MODULE_AUTHOR("Yauheni Kaliuta");
 195 MODULE_LICENSE("GPL");
 196
 197 static int __init init(void)
 198 {
 199         return usb_composite_probe(&ncm_driver);
 200 }
 201 module_init(init);
 202
 203 static void __exit cleanup(void)
 204 {
 205         usb_composite_unregister(&ncm_driver);
 206 }
 207 module_exit(cleanup);