xref: /openbmc/linux/drivers/usb/gadget/legacy/audio.c (revision 3932b9ca)
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/module.h>
16 #include <linux/usb/composite.h>
17 
18 #include "gadget_chips.h"
19 #define DRIVER_DESC		"Linux USB Audio Gadget"
20 #define DRIVER_VERSION		"Feb 2, 2012"
21 
22 USB_GADGET_COMPOSITE_OPTIONS();
23 
24 /* string IDs are assigned dynamically */
25 
26 static struct usb_string strings_dev[] = {
27 	[USB_GADGET_MANUFACTURER_IDX].s = "",
28 	[USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
29 	[USB_GADGET_SERIAL_IDX].s = "",
30 	{  } /* end of list */
31 };
32 
33 static struct usb_gadget_strings stringtab_dev = {
34 	.language = 0x0409,	/* en-us */
35 	.strings = strings_dev,
36 };
37 
38 static struct usb_gadget_strings *audio_strings[] = {
39 	&stringtab_dev,
40 	NULL,
41 };
42 
43 #ifdef CONFIG_GADGET_UAC1
44 #include "u_uac1.h"
45 #include "u_uac1.c"
46 #include "f_uac1.c"
47 #else
48 #include "f_uac2.c"
49 #endif
50 
51 /*-------------------------------------------------------------------------*/
52 
53 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
54  * Instead:  allocate your own, using normal USB-IF procedures.
55  */
56 
57 /* Thanks to Linux Foundation for donating this product ID. */
58 #define AUDIO_VENDOR_NUM		0x1d6b	/* Linux Foundation */
59 #define AUDIO_PRODUCT_NUM		0x0101	/* Linux-USB Audio Gadget */
60 
61 /*-------------------------------------------------------------------------*/
62 
63 static struct usb_device_descriptor device_desc = {
64 	.bLength =		sizeof device_desc,
65 	.bDescriptorType =	USB_DT_DEVICE,
66 
67 	.bcdUSB =		__constant_cpu_to_le16(0x200),
68 
69 #ifdef CONFIG_GADGET_UAC1
70 	.bDeviceClass =		USB_CLASS_PER_INTERFACE,
71 	.bDeviceSubClass =	0,
72 	.bDeviceProtocol =	0,
73 #else
74 	.bDeviceClass =		USB_CLASS_MISC,
75 	.bDeviceSubClass =	0x02,
76 	.bDeviceProtocol =	0x01,
77 #endif
78 	/* .bMaxPacketSize0 = f(hardware) */
79 
80 	/* Vendor and product id defaults change according to what configs
81 	 * we support.  (As does bNumConfigurations.)  These values can
82 	 * also be overridden by module parameters.
83 	 */
84 	.idVendor =		__constant_cpu_to_le16(AUDIO_VENDOR_NUM),
85 	.idProduct =		__constant_cpu_to_le16(AUDIO_PRODUCT_NUM),
86 	/* .bcdDevice = f(hardware) */
87 	/* .iManufacturer = DYNAMIC */
88 	/* .iProduct = DYNAMIC */
89 	/* NO SERIAL NUMBER */
90 	.bNumConfigurations =	1,
91 };
92 
93 static struct usb_otg_descriptor otg_descriptor = {
94 	.bLength =		sizeof otg_descriptor,
95 	.bDescriptorType =	USB_DT_OTG,
96 
97 	/* REVISIT SRP-only hardware is possible, although
98 	 * it would not be called "OTG" ...
99 	 */
100 	.bmAttributes =		USB_OTG_SRP | USB_OTG_HNP,
101 };
102 
103 static const struct usb_descriptor_header *otg_desc[] = {
104 	(struct usb_descriptor_header *) &otg_descriptor,
105 	NULL,
106 };
107 
108 /*-------------------------------------------------------------------------*/
109 
110 static int __init audio_do_config(struct usb_configuration *c)
111 {
112 	/* FIXME alloc iConfiguration string, set it in c->strings */
113 
114 	if (gadget_is_otg(c->cdev->gadget)) {
115 		c->descriptors = otg_desc;
116 		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
117 	}
118 
119 	audio_bind_config(c);
120 
121 	return 0;
122 }
123 
124 static struct usb_configuration audio_config_driver = {
125 	.label			= DRIVER_DESC,
126 	.bConfigurationValue	= 1,
127 	/* .iConfiguration = DYNAMIC */
128 	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
129 #ifndef CONFIG_GADGET_UAC1
130 	.unbind			= uac2_unbind_config,
131 #endif
132 };
133 
134 /*-------------------------------------------------------------------------*/
135 
136 static int __init audio_bind(struct usb_composite_dev *cdev)
137 {
138 	int			status;
139 
140 	status = usb_string_ids_tab(cdev, strings_dev);
141 	if (status < 0)
142 		goto fail;
143 	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
144 	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
145 
146 	status = usb_add_config(cdev, &audio_config_driver, audio_do_config);
147 	if (status < 0)
148 		goto fail;
149 	usb_composite_overwrite_options(cdev, &coverwrite);
150 
151 	INFO(cdev, "%s, version: %s\n", DRIVER_DESC, DRIVER_VERSION);
152 	return 0;
153 
154 fail:
155 	return status;
156 }
157 
158 static int __exit audio_unbind(struct usb_composite_dev *cdev)
159 {
160 #ifdef CONFIG_GADGET_UAC1
161 	gaudio_cleanup();
162 #endif
163 	return 0;
164 }
165 
166 static __refdata struct usb_composite_driver audio_driver = {
167 	.name		= "g_audio",
168 	.dev		= &device_desc,
169 	.strings	= audio_strings,
170 	.max_speed	= USB_SPEED_HIGH,
171 	.bind		= audio_bind,
172 	.unbind		= __exit_p(audio_unbind),
173 };
174 
175 module_usb_composite_driver(audio_driver);
176 
177 MODULE_DESCRIPTION(DRIVER_DESC);
178 MODULE_AUTHOR("Bryan Wu <cooloney@kernel.org>");
179 MODULE_LICENSE("GPL");
180 
181