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
39 static char manufacturer[50];
40
41 static struct usb_string strings_dev[] = {
42 [STRING_MANUFACTURER_IDX].s = manufacturer,
43 [STRING_PRODUCT_IDX].s = DRIVER_DESC,
44 { } /* end of list */
45 };
46
47 static struct usb_gadget_strings stringtab_dev = {
48 .language = 0x0409, /* en-us */
49 .strings = strings_dev,
50 };
51
52 static 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
77 static 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
107 static 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
117 static const struct usb_descriptor_header *otg_desc[] = {
118 (struct usb_descriptor_header *) &otg_descriptor,
119 NULL,
120 };
121
122 /*-------------------------------------------------------------------------*/
123
audio_do_config(struct usb_configuration * c)124 static 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
138 static 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
audio_bind(struct usb_composite_dev * cdev)150 static 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
189 fail:
190 return status;
191 }
192
audio_unbind(struct usb_composite_dev * cdev)193 static 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
201 static 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
init(void)209 static int __init init(void)
210 {
211 return usb_composite_probe(&audio_driver, audio_bind);
212 }
213 module_init(init);
214
cleanup(void)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
225