drivers/usb/gadget/audio.c

   1 /*
   2  * audio.c -- Audio gadget driver
   3  *
   4  * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
   5  * Copyright (C) 2008 Analog Devices, Inc
   6  *
   7  * Enter bugs at http://blackfin.uclinux.org/
   8  *
   9  * Licensed under the GPL-2 or later.
  10  */
  11
  12 /* #define VERBOSE_DEBUG */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/utsname.h>
  16
  17 #define DRIVER_DESC             "Linux USB Audio Gadget"
  18 #define DRIVER_VERSION          "Feb 2, 2012"
  19
  20 /*-------------------------------------------------------------------------*/
  21
  22 /*
  23  * Kbuild is not very cooperative with respect to linking separately
  24  * compiled library objects into one module.  So for now we won't use
  25  * separate compilation ... ensuring init/exit sections work to shrink
  26  * the runtime footprint, and giving us at least some parts of what
  27  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
  28  */
  29 #include "composite.c"
  30 #include "usbstring.c"
  31 #include "config.c"
  32 #include "epautoconf.c"
  33
  34 /* string IDs are assigned dynamically */
  35
  36 #define STRING_MANUFACTURER_IDX         0
  37 #define STRING_PRODUCT_IDX              1
  38
  39 static char manufacturer[50];
  40
  41 static struct usb_string strings_dev[] = {
  42         [STRING_MANUFACTURER_IDX].s = manufacturer,
  43         [STRING_PRODUCT_IDX].s = DRIVER_DESC,
  44         {  } /* end of list */
  45 };
  46
  47 static struct usb_gadget_strings stringtab_dev = {
  48         .language = 0x0409,     /* en-us */
  49         .strings = strings_dev,
  50 };
  51
  52 static struct usb_gadget_strings *audio_strings[] = {
  53         &stringtab_dev,
  54         NULL,
  55 };
  56
  57 #ifdef CONFIG_GADGET_UAC1
  58 #include "u_uac1.h"
  59 #include "u_uac1.c"
  60 #include "f_uac1.c"
  61 #else
  62 #include "f_uac2.c"
  63 #endif
  64
  65 /*-------------------------------------------------------------------------*/
  66
  67 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  68  * Instead:  allocate your own, using normal USB-IF procedures.
  69  */
  70
  71 /* Thanks to Linux Foundation for donating this product ID. */
  72 #define AUDIO_VENDOR_NUM                0x1d6b  /* Linux Foundation */
  73 #define AUDIO_PRODUCT_NUM               0x0101  /* Linux-USB Audio Gadget */
  74
  75 /*-------------------------------------------------------------------------*/
  76
  77 static struct usb_device_descriptor device_desc = {
  78         .bLength =              sizeof device_desc,
  79         .bDescriptorType =      USB_DT_DEVICE,
  80
  81         .bcdUSB =               __constant_cpu_to_le16(0x200),
  82
  83 #ifdef CONFIG_GADGET_UAC1
  84         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
  85         .bDeviceSubClass =      0,
  86         .bDeviceProtocol =      0,
  87 #else
  88         .bDeviceClass =         USB_CLASS_MISC,
  89         .bDeviceSubClass =      0x02,
  90         .bDeviceProtocol =      0x01,
  91 #endif
  92         /* .bMaxPacketSize0 = f(hardware) */
  93
  94         /* Vendor and product id defaults change according to what configs
  95          * we support.  (As does bNumConfigurations.)  These values can
  96          * also be overridden by module parameters.
  97          */
  98         .idVendor =             __constant_cpu_to_le16(AUDIO_VENDOR_NUM),
  99         .idProduct =            __constant_cpu_to_le16(AUDIO_PRODUCT_NUM),
 100         /* .bcdDevice = f(hardware) */
 101         /* .iManufacturer = DYNAMIC */
 102         /* .iProduct = DYNAMIC */
 103         /* NO SERIAL NUMBER */
 104         .bNumConfigurations =   1,
 105 };
 106
 107 static struct usb_otg_descriptor otg_descriptor = {
 108         .bLength =              sizeof otg_descriptor,
 109         .bDescriptorType =      USB_DT_OTG,
 110
 111         /* REVISIT SRP-only hardware is possible, although
 112          * it would not be called "OTG" ...
 113          */
 114         .bmAttributes =         USB_OTG_SRP | USB_OTG_HNP,
 115 };
 116
 117 static const struct usb_descriptor_header *otg_desc[] = {
 118         (struct usb_descriptor_header *) &otg_descriptor,
 119         NULL,
 120 };
 121
 122 /*-------------------------------------------------------------------------*/
 123
 124 static int __init audio_do_config(struct usb_configuration *c)
 125 {
 126         /* FIXME alloc iConfiguration string, set it in c->strings */
 127
 128         if (gadget_is_otg(c->cdev->gadget)) {
 129                 c->descriptors = otg_desc;
 130                 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 131         }
 132
 133         audio_bind_config(c);
 134
 135         return 0;
 136 }
 137
 138 static struct usb_configuration audio_config_driver = {
 139         .label                  = DRIVER_DESC,
 140         .bConfigurationValue    = 1,
 141         /* .iConfiguration = DYNAMIC */
 142         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
 143 #ifndef CONFIG_GADGET_UAC1
 144         .unbind                 = uac2_unbind_config,
 145 #endif
 146 };
 147
 148 /*-------------------------------------------------------------------------*/
 149
 150 static int __init audio_bind(struct usb_composite_dev *cdev)
 151 {
 152         int                     gcnum;
 153         int                     status;
 154
 155         gcnum = usb_gadget_controller_number(cdev->gadget);
 156         if (gcnum >= 0)
 157                 device_desc.bcdDevice = cpu_to_le16(0x0300 | gcnum);
 158         else {
 159                 ERROR(cdev, "controller '%s' not recognized; trying %s\n",
 160                         cdev->gadget->name,
 161                         audio_config_driver.label);
 162                 device_desc.bcdDevice =
 163                         __constant_cpu_to_le16(0x0300 | 0x0099);
 164         }
 165
 166         /* device descriptor strings: manufacturer, product */
 167         snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
 168                 init_utsname()->sysname, init_utsname()->release,
 169                 cdev->gadget->name);
 170         status = usb_string_id(cdev);
 171         if (status < 0)
 172                 goto fail;
 173         strings_dev[STRING_MANUFACTURER_IDX].id = status;
 174         device_desc.iManufacturer = status;
 175
 176         status = usb_string_id(cdev);
 177         if (status < 0)
 178                 goto fail;
 179         strings_dev[STRING_PRODUCT_IDX].id = status;
 180         device_desc.iProduct = status;
 181
 182         status = usb_add_config(cdev, &audio_config_driver, audio_do_config);
 183         if (status < 0)
 184                 goto fail;
 185
 186         INFO(cdev, "%s, version: %s\n", DRIVER_DESC, DRIVER_VERSION);
 187         return 0;
 188
 189 fail:
 190         return status;
 191 }
 192
 193 static int __exit audio_unbind(struct usb_composite_dev *cdev)
 194 {
 195 #ifdef CONFIG_GADGET_UAC1
 196         gaudio_cleanup();
 197 #endif
 198         return 0;
 199 }
 200
 201 static struct usb_composite_driver audio_driver = {
 202         .name           = "g_audio",
 203         .dev            = &device_desc,
 204         .strings        = audio_strings,
 205         .max_speed      = USB_SPEED_HIGH,
 206         .unbind         = __exit_p(audio_unbind),
 207 };
 208
 209 static int __init init(void)
 210 {
 211         return usb_composite_probe(&audio_driver, audio_bind);
 212 }
 213 module_init(init);
 214
 215 static void __exit cleanup(void)
 216 {
 217         usb_composite_unregister(&audio_driver);
 218 }
 219 module_exit(cleanup);
 220
 221 MODULE_DESCRIPTION(DRIVER_DESC);
 222 MODULE_AUTHOR("Bryan Wu <cooloney@kernel.org>");
 223 MODULE_LICENSE("GPL");
 224