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
 39static char manufacturer[50];
 40
 41static struct usb_string strings_dev[] = {
 42	[STRING_MANUFACTURER_IDX].s = manufacturer,
 43	[STRING_PRODUCT_IDX].s = DRIVER_DESC,
 44	{  } /* end of list */
 45};
 46
 47static struct usb_gadget_strings stringtab_dev = {
 48	.language = 0x0409,	/* en-us */
 49	.strings = strings_dev,
 50};
 51
 52static 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
 77static 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
107static 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
117static const struct usb_descriptor_header *otg_desc[] = {
118	(struct usb_descriptor_header *) &otg_descriptor,
119	NULL,
120};
121
122/*-------------------------------------------------------------------------*/
123
124static 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
138static 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
150static 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
189fail:
190	return status;
191}
192
193static 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
201static 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
209static int __init init(void)
210{
211	return usb_composite_probe(&audio_driver, audio_bind);
212}
213module_init(init);
214
215static void __exit cleanup(void)
216{
217	usb_composite_unregister(&audio_driver);
218}
219module_exit(cleanup);
220
221MODULE_DESCRIPTION(DRIVER_DESC);
222MODULE_AUTHOR("Bryan Wu <cooloney@kernel.org>");
223MODULE_LICENSE("GPL");
224