kernel/drivers/usb/gadget/legacy/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 #include "u_ncm.h"
  28
  29 #define DRIVER_DESC             "NCM Gadget"
  30
  31 /*-------------------------------------------------------------------------*/
  32
  33 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  34  * Instead:  allocate your own, using normal USB-IF procedures.
  35  */
  36
  37 /* Thanks to NetChip Technologies for donating this product ID.
  38  * It's for devices with only CDC Ethernet configurations.
  39  */
  40 #define CDC_VENDOR_NUM          0x0525  /* NetChip */
  41 #define CDC_PRODUCT_NUM         0xa4a1  /* Linux-USB Ethernet Gadget */
  42
  43 /*-------------------------------------------------------------------------*/
  44 USB_GADGET_COMPOSITE_OPTIONS();
  45
  46 USB_ETHERNET_MODULE_PARAMETERS();
  47
  48 static struct usb_device_descriptor device_desc = {
  49         .bLength =              sizeof device_desc,
  50         .bDescriptorType =      USB_DT_DEVICE,
  51
  52         .bcdUSB =               cpu_to_le16 (0x0200),
  53
  54         .bDeviceClass =         USB_CLASS_COMM,
  55         .bDeviceSubClass =      0,
  56         .bDeviceProtocol =      0,
  57         /* .bMaxPacketSize0 = f(hardware) */
  58
  59         /* Vendor and product id defaults change according to what configs
  60          * we support.  (As does bNumConfigurations.)  These values can
  61          * also be overridden by module parameters.
  62          */
  63         .idVendor =             cpu_to_le16 (CDC_VENDOR_NUM),
  64         .idProduct =            cpu_to_le16 (CDC_PRODUCT_NUM),
  65         /* .bcdDevice = f(hardware) */
  66         /* .iManufacturer = DYNAMIC */
  67         /* .iProduct = DYNAMIC */
  68         /* NO SERIAL NUMBER */
  69         .bNumConfigurations =   1,
  70 };
  71
  72 static const struct usb_descriptor_header *otg_desc[2];
  73
  74 /* string IDs are assigned dynamically */
  75 static struct usb_string strings_dev[] = {
  76         [USB_GADGET_MANUFACTURER_IDX].s = "",
  77         [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
  78         [USB_GADGET_SERIAL_IDX].s = "",
  79         {  } /* end of list */
  80 };
  81
  82 static struct usb_gadget_strings stringtab_dev = {
  83         .language       = 0x0409,       /* en-us */
  84         .strings        = strings_dev,
  85 };
  86
  87 static struct usb_gadget_strings *dev_strings[] = {
  88         &stringtab_dev,
  89         NULL,
  90 };
  91
  92 static struct usb_function_instance *f_ncm_inst;
  93 static struct usb_function *f_ncm;
  94
  95 /*-------------------------------------------------------------------------*/
  96
  97 static int ncm_do_config(struct usb_configuration *c)
  98 {
  99         int status;
 100
 101         /* FIXME alloc iConfiguration string, set it in c->strings */
 102
 103         if (gadget_is_otg(c->cdev->gadget)) {
 104                 c->descriptors = otg_desc;
 105                 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 106         }
 107
 108         f_ncm = usb_get_function(f_ncm_inst);
 109         if (IS_ERR(f_ncm)) {
 110                 status = PTR_ERR(f_ncm);
 111                 return status;
 112         }
 113
 114         status = usb_add_function(c, f_ncm);
 115         if (status < 0) {
 116                 usb_put_function(f_ncm);
 117                 return status;
 118         }
 119
 120         return 0;
 121 }
 122
 123 static struct usb_configuration ncm_config_driver = {
 124         /* .label = f(hardware) */
 125         .label                  = "CDC Ethernet (NCM)",
 126         .bConfigurationValue    = 1,
 127         /* .iConfiguration = DYNAMIC */
 128         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
 129 };
 130
 131 /*-------------------------------------------------------------------------*/
 132
 133 static int gncm_bind(struct usb_composite_dev *cdev)
 134 {
 135         struct usb_gadget       *gadget = cdev->gadget;
 136         struct f_ncm_opts       *ncm_opts;
 137         int                     status;
 138
 139         f_ncm_inst = usb_get_function_instance("ncm");
 140         if (IS_ERR(f_ncm_inst))
 141                 return PTR_ERR(f_ncm_inst);
 142
 143         ncm_opts = container_of(f_ncm_inst, struct f_ncm_opts, func_inst);
 144
 145         gether_set_qmult(ncm_opts->net, qmult);
 146         if (!gether_set_host_addr(ncm_opts->net, host_addr))
 147                 pr_info("using host ethernet address: %s", host_addr);
 148         if (!gether_set_dev_addr(ncm_opts->net, dev_addr))
 149                 pr_info("using self ethernet address: %s", dev_addr);
 150
 151         /* Allocate string descriptor numbers ... note that string
 152          * contents can be overridden by the composite_dev glue.
 153          */
 154
 155         status = usb_string_ids_tab(cdev, strings_dev);
 156         if (status < 0)
 157                 goto fail;
 158         device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 159         device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 160
 161         if (gadget_is_otg(gadget) && !otg_desc[0]) {
 162                 struct usb_descriptor_header *usb_desc;
 163
 164                 usb_desc = usb_otg_descriptor_alloc(gadget);
 165                 if (!usb_desc)
 166                         goto fail;
 167                 usb_otg_descriptor_init(gadget, usb_desc);
 168                 otg_desc[0] = usb_desc;
 169                 otg_desc[1] = NULL;
 170         }
 171
 172         status = usb_add_config(cdev, &ncm_config_driver,
 173                                 ncm_do_config);
 174         if (status < 0)
 175                 goto fail1;
 176
 177         usb_composite_overwrite_options(cdev, &coverwrite);
 178         dev_info(&gadget->dev, "%s\n", DRIVER_DESC);
 179
 180         return 0;
 181
 182 fail1:
 183         kfree(otg_desc[0]);
 184         otg_desc[0] = NULL;
 185 fail:
 186         usb_put_function_instance(f_ncm_inst);
 187         return status;
 188 }
 189
 190 static int gncm_unbind(struct usb_composite_dev *cdev)
 191 {
 192         if (!IS_ERR_OR_NULL(f_ncm))
 193                 usb_put_function(f_ncm);
 194         if (!IS_ERR_OR_NULL(f_ncm_inst))
 195                 usb_put_function_instance(f_ncm_inst);
 196         kfree(otg_desc[0]);
 197         otg_desc[0] = NULL;
 198
 199         return 0;
 200 }
 201
 202 static struct usb_composite_driver ncm_driver = {
 203         .name           = "g_ncm",
 204         .dev            = &device_desc,
 205         .strings        = dev_strings,
 206         .max_speed      = USB_SPEED_HIGH,
 207         .bind           = gncm_bind,
 208         .unbind         = gncm_unbind,
 209 };
 210
 211 module_usb_composite_driver(ncm_driver);
 212
 213 MODULE_DESCRIPTION(DRIVER_DESC);
 214 MODULE_AUTHOR("Yauheni Kaliuta");
 215 MODULE_LICENSE("GPL");