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