drivers/usb/gadget/cdc2.c

   1 /*
   2  * cdc2.c -- CDC Composite driver, with ECM and ACM support
   3  *
   4  * Copyright (C) 2008 David Brownell
   5  * Copyright (C) 2008 Nokia Corporation
   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 #include <linux/kernel.h>
  14 #include <linux/utsname.h>
  15 #include <linux/module.h>
  16
  17 #include "u_ether.h"
  18 #include "u_serial.h"
  19
  20
  21 #define DRIVER_DESC             "CDC Composite Gadget"
  22 #define DRIVER_VERSION          "King Kamehameha Day 2008"
  23
  24 /*-------------------------------------------------------------------------*/
  25
  26 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  27  * Instead:  allocate your own, using normal USB-IF procedures.
  28  */
  29
  30 /* Thanks to NetChip Technologies for donating this product ID.
  31  * It's for devices with only this composite CDC configuration.
  32  */
  33 #define CDC_VENDOR_NUM          0x0525  /* NetChip */
  34 #define CDC_PRODUCT_NUM         0xa4aa  /* CDC Composite: ECM + ACM */
  35
  36 /*-------------------------------------------------------------------------*/
  37
  38 /*
  39  * Kbuild is not very cooperative with respect to linking separately
  40  * compiled library objects into one module.  So for now we won't use
  41  * separate compilation ... ensuring init/exit sections work to shrink
  42  * the runtime footprint, and giving us at least some parts of what
  43  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
  44  */
  45
  46 #include "composite.c"
  47 #include "u_serial.c"
  48 #include "f_acm.c"
  49 #include "f_ecm.c"
  50 #include "u_ether.c"
  51
  52 /*-------------------------------------------------------------------------*/
  53
  54 static struct usb_device_descriptor device_desc = {
  55         .bLength =              sizeof device_desc,
  56         .bDescriptorType =      USB_DT_DEVICE,
  57
  58         .bcdUSB =               cpu_to_le16(0x0200),
  59
  60         .bDeviceClass =         USB_CLASS_COMM,
  61         .bDeviceSubClass =      0,
  62         .bDeviceProtocol =      0,
  63         /* .bMaxPacketSize0 = f(hardware) */
  64
  65         /* Vendor and product id can be overridden by module parameters.  */
  66         .idVendor =             cpu_to_le16(CDC_VENDOR_NUM),
  67         .idProduct =            cpu_to_le16(CDC_PRODUCT_NUM),
  68         /* .bcdDevice = f(hardware) */
  69         /* .iManufacturer = DYNAMIC */
  70         /* .iProduct = DYNAMIC */
  71         /* NO SERIAL NUMBER */
  72         .bNumConfigurations =   1,
  73 };
  74
  75 static struct usb_otg_descriptor otg_descriptor = {
  76         .bLength =              sizeof otg_descriptor,
  77         .bDescriptorType =      USB_DT_OTG,
  78
  79         /* REVISIT SRP-only hardware is possible, although
  80          * it would not be called "OTG" ...
  81          */
  82         .bmAttributes =         USB_OTG_SRP | USB_OTG_HNP,
  83 };
  84
  85 static const struct usb_descriptor_header *otg_desc[] = {
  86         (struct usb_descriptor_header *) &otg_descriptor,
  87         NULL,
  88 };
  89
  90
  91 /* string IDs are assigned dynamically */
  92
  93 #define STRING_MANUFACTURER_IDX         0
  94 #define STRING_PRODUCT_IDX              1
  95
  96 static char manufacturer[50];
  97
  98 static struct usb_string strings_dev[] = {
  99         [STRING_MANUFACTURER_IDX].s = manufacturer,
 100         [STRING_PRODUCT_IDX].s = DRIVER_DESC,
 101         {  } /* end of list */
 102 };
 103
 104 static struct usb_gadget_strings stringtab_dev = {
 105         .language       = 0x0409,       /* en-us */
 106         .strings        = strings_dev,
 107 };
 108
 109 static struct usb_gadget_strings *dev_strings[] = {
 110         &stringtab_dev,
 111         NULL,
 112 };
 113
 114 static u8 hostaddr[ETH_ALEN];
 115
 116 /*-------------------------------------------------------------------------*/
 117
 118 /*
 119  * We _always_ have both CDC ECM and CDC ACM functions.
 120  */
 121 static int __init cdc_do_config(struct usb_configuration *c)
 122 {
 123         int     status;
 124
 125         if (gadget_is_otg(c->cdev->gadget)) {
 126                 c->descriptors = otg_desc;
 127                 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 128         }
 129
 130         status = ecm_bind_config(c, hostaddr);
 131         if (status < 0)
 132                 return status;
 133
 134         status = acm_bind_config(c, 0);
 135         if (status < 0)
 136                 return status;
 137
 138         return 0;
 139 }
 140
 141 static struct usb_configuration cdc_config_driver = {
 142         .label                  = "CDC Composite (ECM + ACM)",
 143         .bConfigurationValue    = 1,
 144         /* .iConfiguration = DYNAMIC */
 145         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
 146 };
 147
 148 /*-------------------------------------------------------------------------*/
 149
 150 static int __init cdc_bind(struct usb_composite_dev *cdev)
 151 {
 152         int                     gcnum;
 153         struct usb_gadget       *gadget = cdev->gadget;
 154         int                     status;
 155
 156         if (!can_support_ecm(cdev->gadget)) {
 157                 dev_err(&gadget->dev, "controller '%s' not usable\n",
 158                                 gadget->name);
 159                 return -EINVAL;
 160         }
 161
 162         /* set up network link layer */
 163         status = gether_setup(cdev->gadget, hostaddr);
 164         if (status < 0)
 165                 return status;
 166
 167         /* set up serial link layer */
 168         status = gserial_setup(cdev->gadget, 1);
 169         if (status < 0)
 170                 goto fail0;
 171
 172         gcnum = usb_gadget_controller_number(gadget);
 173         if (gcnum >= 0)
 174                 device_desc.bcdDevice = cpu_to_le16(0x0300 | gcnum);
 175         else {
 176                 /* We assume that can_support_ecm() tells the truth;
 177                  * but if the controller isn't recognized at all then
 178                  * that assumption is a bit more likely to be wrong.
 179                  */
 180                 WARNING(cdev, "controller '%s' not recognized; trying %s\n",
 181                                 gadget->name,
 182                                 cdc_config_driver.label);
 183                 device_desc.bcdDevice =
 184                         cpu_to_le16(0x0300 | 0x0099);
 185         }
 186
 187
 188         /* Allocate string descriptor numbers ... note that string
 189          * contents can be overridden by the composite_dev glue.
 190          */
 191
 192         /* device descriptor strings: manufacturer, product */
 193         snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
 194                 init_utsname()->sysname, init_utsname()->release,
 195                 gadget->name);
 196         status = usb_string_ids_tab(cdev, strings_dev);
 197         if (status < 0)
 198                 goto fail1;
 199         device_desc.iManufacturer = strings_dev[STRING_MANUFACTURER_IDX].id;
 200         device_desc.iProduct = strings_dev[STRING_PRODUCT_IDX].id;
 201
 202         /* register our configuration */
 203         status = usb_add_config(cdev, &cdc_config_driver, cdc_do_config);
 204         if (status < 0)
 205                 goto fail1;
 206
 207         dev_info(&gadget->dev, "%s, version: " DRIVER_VERSION "\n",
 208                         DRIVER_DESC);
 209
 210         return 0;
 211
 212 fail1:
 213         gserial_cleanup();
 214 fail0:
 215         gether_cleanup();
 216         return status;
 217 }
 218
 219 static int __exit cdc_unbind(struct usb_composite_dev *cdev)
 220 {
 221         gserial_cleanup();
 222         gether_cleanup();
 223         return 0;
 224 }
 225
 226 static __refdata struct usb_composite_driver cdc_driver = {
 227         .name           = "g_cdc",
 228         .dev            = &device_desc,
 229         .strings        = dev_strings,
 230         .max_speed      = USB_SPEED_HIGH,
 231         .bind           = cdc_bind,
 232         .unbind         = __exit_p(cdc_unbind),
 233 };
 234
 235 MODULE_DESCRIPTION(DRIVER_DESC);
 236 MODULE_AUTHOR("David Brownell");
 237 MODULE_LICENSE("GPL");
 238
 239 static int __init init(void)
 240 {
 241         return usb_composite_probe(&cdc_driver);
 242 }
 243 module_init(init);
 244
 245 static void __exit cleanup(void)
 246 {
 247         usb_composite_unregister(&cdc_driver);
 248 }
 249 module_exit(cleanup);