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 "config.c"
  31 #include "epautoconf.c"
  32
  33 /* string IDs are assigned dynamically */
  34
  35 #define STRING_MANUFACTURER_IDX         0
  36 #define STRING_PRODUCT_IDX              1
  37
  38 static char manufacturer[50];
  39
  40 static struct usb_string strings_dev[] = {
  41         [STRING_MANUFACTURER_IDX].s = manufacturer,
  42         [STRING_PRODUCT_IDX].s = DRIVER_DESC,
  43         {  } /* end of list */
  44 };
  45
  46 static struct usb_gadget_strings stringtab_dev = {
  47         .language = 0x0409,     /* en-us */
  48         .strings = strings_dev,
  49 };
  50
  51 static struct usb_gadget_strings *audio_strings[] = {
  52         &stringtab_dev,
  53         NULL,
  54 };
  55
  56 #ifdef CONFIG_GADGET_UAC1
  57 #include "u_uac1.h"
  58 #include "u_uac1.c"
  59 #include "f_uac1.c"
  60 #else
  61 #include "f_uac2.c"
  62 #endif
  63
  64 /*-------------------------------------------------------------------------*/
  65
  66 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  67  * Instead:  allocate your own, using normal USB-IF procedures.
  68  */
  69
  70 /* Thanks to Linux Foundation for donating this product ID. */
  71 #define AUDIO_VENDOR_NUM                0x1d6b  /* Linux Foundation */
  72 #define AUDIO_PRODUCT_NUM               0x0101  /* Linux-USB Audio Gadget */
  73
  74 /*-------------------------------------------------------------------------*/
  75
  76 static struct usb_device_descriptor device_desc = {
  77         .bLength =              sizeof device_desc,
  78         .bDescriptorType =      USB_DT_DEVICE,
  79
  80         .bcdUSB =               __constant_cpu_to_le16(0x200),
  81
  82 #ifdef CONFIG_GADGET_UAC1
  83         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
  84         .bDeviceSubClass =      0,
  85         .bDeviceProtocol =      0,
  86 #else
  87         .bDeviceClass =         USB_CLASS_MISC,
  88         .bDeviceSubClass =      0x02,
  89         .bDeviceProtocol =      0x01,
  90 #endif
  91         /* .bMaxPacketSize0 = f(hardware) */
  92
  93         /* Vendor and product id defaults change according to what configs
  94          * we support.  (As does bNumConfigurations.)  These values can
  95          * also be overridden by module parameters.
  96          */
  97         .idVendor =             __constant_cpu_to_le16(AUDIO_VENDOR_NUM),
  98         .idProduct =            __constant_cpu_to_le16(AUDIO_PRODUCT_NUM),
  99         /* .bcdDevice = f(hardware) */
 100         /* .iManufacturer = DYNAMIC */
 101         /* .iProduct = DYNAMIC */
 102         /* NO SERIAL NUMBER */
 103         .bNumConfigurations =   1,
 104 };
 105
 106 static struct usb_otg_descriptor otg_descriptor = {
 107         .bLength =              sizeof otg_descriptor,
 108         .bDescriptorType =      USB_DT_OTG,
 109
 110         /* REVISIT SRP-only hardware is possible, although
 111          * it would not be called "OTG" ...
 112          */
 113         .bmAttributes =         USB_OTG_SRP | USB_OTG_HNP,
 114 };
 115
 116 static const struct usb_descriptor_header *otg_desc[] = {
 117         (struct usb_descriptor_header *) &otg_descriptor,
 118         NULL,
 119 };
 120
 121 /*-------------------------------------------------------------------------*/
 122
 123 static int __init audio_do_config(struct usb_configuration *c)
 124 {
 125         /* FIXME alloc iConfiguration string, set it in c->strings */
 126
 127         if (gadget_is_otg(c->cdev->gadget)) {
 128                 c->descriptors = otg_desc;
 129                 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 130         }
 131
 132         audio_bind_config(c);
 133
 134         return 0;
 135 }
 136
 137 static struct usb_configuration audio_config_driver = {
 138         .label                  = DRIVER_DESC,
 139         .bConfigurationValue    = 1,
 140         /* .iConfiguration = DYNAMIC */
 141         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
 142 #ifndef CONFIG_GADGET_UAC1
 143         .unbind                 = uac2_unbind_config,
 144 #endif
 145 };
 146
 147 /*-------------------------------------------------------------------------*/
 148
 149 static int __init audio_bind(struct usb_composite_dev *cdev)
 150 {
 151         int                     gcnum;
 152         int                     status;
 153
 154         gcnum = usb_gadget_controller_number(cdev->gadget);
 155         if (gcnum >= 0)
 156                 device_desc.bcdDevice = cpu_to_le16(0x0300 | gcnum);
 157         else {
 158                 ERROR(cdev, "controller '%s' not recognized; trying %s\n",
 159                         cdev->gadget->name,
 160                         audio_config_driver.label);
 161                 device_desc.bcdDevice =
 162                         __constant_cpu_to_le16(0x0300 | 0x0099);
 163         }
 164
 165         /* device descriptor strings: manufacturer, product */
 166         snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
 167                 init_utsname()->sysname, init_utsname()->release,
 168                 cdev->gadget->name);
 169         status = usb_string_id(cdev);
 170         if (status < 0)
 171                 goto fail;
 172         strings_dev[STRING_MANUFACTURER_IDX].id = status;
 173         device_desc.iManufacturer = status;
 174
 175         status = usb_string_id(cdev);
 176         if (status < 0)
 177                 goto fail;
 178         strings_dev[STRING_PRODUCT_IDX].id = status;
 179         device_desc.iProduct = status;
 180
 181         status = usb_add_config(cdev, &audio_config_driver, audio_do_config);
 182         if (status < 0)
 183                 goto fail;
 184
 185         INFO(cdev, "%s, version: %s\n", DRIVER_DESC, DRIVER_VERSION);
 186         return 0;
 187
 188 fail:
 189         return status;
 190 }
 191
 192 static int __exit audio_unbind(struct usb_composite_dev *cdev)
 193 {
 194 #ifdef CONFIG_GADGET_UAC1
 195         gaudio_cleanup();
 196 #endif
 197         return 0;
 198 }
 199
 200 static __refdata struct usb_composite_driver audio_driver = {
 201         .name           = "g_audio",
 202         .dev            = &device_desc,
 203         .strings        = audio_strings,
 204         .max_speed      = USB_SPEED_HIGH,
 205         .bind           = audio_bind,
 206         .unbind         = __exit_p(audio_unbind),
 207 };
 208
 209 static int __init init(void)
 210 {
 211         return usb_composite_probe(&audio_driver);
 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