summaryrefslogtreecommitdiffstats
path: root/drivers/usb/gadget/audio.c
blob: 9d89ae4765a92c867410601cd3d89c445c96175e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
/*
 * audio.c -- Audio gadget driver
 *
 * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
 * Copyright (C) 2008 Analog Devices, Inc
 *
 * Enter bugs at http://blackfin.uclinux.org/
 *
 * Licensed under the GPL-2 or later.
 */

/* #define VERBOSE_DEBUG */

#include <linux/kernel.h>
#include <linux/utsname.h>

#include "u_audio.h"

#define DRIVER_DESC		"Linux USB Audio Gadget"
#define DRIVER_VERSION		"Dec 18, 2008"

/*-------------------------------------------------------------------------*/

/*
 * Kbuild is not very cooperative with respect to linking separately
 * compiled library objects into one module.  So for now we won't use
 * separate compilation ... ensuring init/exit sections work to shrink
 * the runtime footprint, and giving us at least some parts of what
 * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
 */
#include "composite.c"
#include "usbstring.c"
#include "config.c"
#include "epautoconf.c"

#include "u_audio.c"
#include "f_audio.c"

/*-------------------------------------------------------------------------*/

/* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
 * Instead:  allocate your own, using normal USB-IF procedures.
 */

/* Thanks to Linux Foundation for donating this product ID. */
#define AUDIO_VENDOR_NUM		0x1d6b	/* Linux Foundation */
#define AUDIO_PRODUCT_NUM		0x0101	/* Linux-USB Audio Gadget */

/*-------------------------------------------------------------------------*/

static struct usb_device_descriptor device_desc = {
	.bLength =		sizeof device_desc,
	.bDescriptorType =	USB_DT_DEVICE,

	.bcdUSB =		__constant_cpu_to_le16(0x200),

	.bDeviceClass =		USB_CLASS_PER_INTERFACE,
	.bDeviceSubClass =	0,
	.bDeviceProtocol =	0,
	/* .bMaxPacketSize0 = f(hardware) */

	/* Vendor and product id defaults change according to what configs
	 * we support.  (As does bNumConfigurations.)  These values can
	 * also be overridden by module parameters.
	 */
	.idVendor =		__constant_cpu_to_le16(AUDIO_VENDOR_NUM),
	.idProduct =		__constant_cpu_to_le16(AUDIO_PRODUCT_NUM),
	/* .bcdDevice = f(hardware) */
	/* .iManufacturer = DYNAMIC */
	/* .iProduct = DYNAMIC */
	/* NO SERIAL NUMBER */
	.bNumConfigurations =	1,
};

static struct usb_otg_descriptor otg_descriptor = {
	.bLength =		sizeof otg_descriptor,
	.bDescriptorType =	USB_DT_OTG,

	/* REVISIT SRP-only hardware is possible, although
	 * it would not be called "OTG" ...
	 */
	.bmAttributes =		USB_OTG_SRP | USB_OTG_HNP,
};

static const struct usb_descriptor_header *otg_desc[] = {
	(struct usb_descriptor_header *) &otg_descriptor,
	NULL,
};

/*-------------------------------------------------------------------------*/

static int __init audio_do_config(struct usb_configuration *c)
{
	/* FIXME alloc iConfiguration string, set it in c->strings */

	if (gadget_is_otg(c->cdev->gadget)) {
		c->descriptors = otg_desc;
		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
	}

	audio_bind_config(c);

	return 0;
}

static struct usb_configuration audio_config_driver = {
	.label			= DRIVER_DESC,
	.bConfigurationValue	= 1,
	/* .iConfiguration = DYNAMIC */
	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
};

/*-------------------------------------------------------------------------*/

static int __init audio_bind(struct usb_composite_dev *cdev)
{
	int			gcnum;
	int			status;

	gcnum = usb_gadget_controller_number(cdev->gadget);
	if (gcnum >= 0)
		device_desc.bcdDevice = cpu_to_le16(0x0300 | gcnum);
	else {
		ERROR(cdev, "controller '%s' not recognized; trying %s\n",
			cdev->gadget->name,
			audio_config_driver.label);
		device_desc.bcdDevice =
			__constant_cpu_to_le16(0x0300 | 0x0099);
	}

	/* device descriptor strings: manufacturer, product */
	snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
		init_utsname()->sysname, init_utsname()->release,
		cdev->gadget->name);
	status = usb_string_id(cdev);
	if (status < 0)
		goto fail;
	strings_dev[STRING_MANUFACTURER_IDX].id = status;
	device_desc.iManufacturer = status;

	status = usb_string_id(cdev);
	if (status < 0)
		goto fail;
	strings_dev[STRING_PRODUCT_IDX].id = status;
	device_desc.iProduct = status;

	status = usb_add_config(cdev, &audio_config_driver, audio_do_config);
	if (status < 0)
		goto fail;

	INFO(cdev, "%s, version: %s\n", DRIVER_DESC, DRIVER_VERSION);
	return 0;

fail:
	return status;
}

static int __exit audio_unbind(struct usb_composite_dev *cdev)
{
	gaudio_cleanup();
	return 0;
}

static struct usb_composite_driver audio_driver = {
	.name		= "g_audio",
	.dev		= &device_desc,
	.strings	= audio_strings,
	.max_speed	= USB_SPEED_HIGH,
	.unbind		= __exit_p(audio_unbind),
};

static int __init init(void)
{
	return usb_composite_probe(&audio_driver, audio_bind);
}
module_init(init);

static void __exit cleanup(void)
{
	usb_composite_unregister(&audio_driver);
}
module_exit(cleanup);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Bryan Wu <cooloney@kernel.org>");
MODULE_LICENSE("GPL");

OpenPOWER on IntegriCloud