1 /*
2 * gmidi.c -- USB MIDI Gadget Driver
3 *
4 * Copyright (C) 2006 Thumtronics Pty Ltd.
5 * Developed for Thumtronics by Grey Innovation
6 * Ben Williamson <ben.williamson@greyinnovation.com>
7 *
8 * This software is distributed under the terms of the GNU General Public
9 * License ("GPL") version 2, as published by the Free Software Foundation.
10 *
11 * This code is based in part on:
12 *
13 * Gadget Zero driver, Copyright (C) 2003-2004 David Brownell.
14 * USB Audio driver, Copyright (C) 2002 by Takashi Iwai.
15 * USB MIDI driver, Copyright (C) 2002-2005 Clemens Ladisch.
16 *
17 * Refer to the USB Device Class Definition for MIDI Devices:
18 * http://www.usb.org/developers/devclass_docs/midi10.pdf
19 */
20
21 /* #define VERBOSE_DEBUG */
22
23 #include <linux/kernel.h>
24 #include <linux/slab.h>
25 #include <linux/utsname.h>
26 #include <linux/module.h>
27 #include <linux/device.h>
28
29 #include <sound/core.h>
30 #include <sound/initval.h>
31 #include <sound/rawmidi.h>
32
33 #include <linux/usb/ch9.h>
34 #include <linux/usb/gadget.h>
35 #include <linux/usb/audio.h>
36 #include <linux/usb/midi.h>
37
38 #include "gadget_chips.h"
39
40 #include "composite.c"
41 #include "usbstring.c"
42 #include "config.c"
43 #include "epautoconf.c"
44 #include "f_midi.c"
45
46 /*-------------------------------------------------------------------------*/
47
48 MODULE_AUTHOR("Ben Williamson");
49 MODULE_LICENSE("GPL v2");
50
51 static const char shortname[] = "g_midi";
52 static const char longname[] = "MIDI Gadget";
53
54 static int index = SNDRV_DEFAULT_IDX1;
55 module_param(index, int, S_IRUGO);
56 MODULE_PARM_DESC(index, "Index value for the USB MIDI Gadget adapter.");
57
58 static char *id = SNDRV_DEFAULT_STR1;
59 module_param(id, charp, S_IRUGO);
60 MODULE_PARM_DESC(id, "ID string for the USB MIDI Gadget adapter.");
61
62 static unsigned int buflen = 256;
63 module_param(buflen, uint, S_IRUGO);
64 MODULE_PARM_DESC(buflen, "MIDI buffer length");
65
66 static unsigned int qlen = 32;
67 module_param(qlen, uint, S_IRUGO);
68 MODULE_PARM_DESC(qlen, "USB read request queue length");
69
70 static unsigned int in_ports = 1;
71 module_param(in_ports, uint, S_IRUGO);
72 MODULE_PARM_DESC(in_ports, "Number of MIDI input ports");
73
74 static unsigned int out_ports = 1;
75 module_param(out_ports, uint, S_IRUGO);
76 MODULE_PARM_DESC(out_ports, "Number of MIDI output ports");
77
78 /* Thanks to Grey Innovation for donating this product ID.
79 *
80 * DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!!
81 * Instead: allocate your own, using normal USB-IF procedures.
82 */
83 #define DRIVER_VENDOR_NUM 0x17b3 /* Grey Innovation */
84 #define DRIVER_PRODUCT_NUM 0x0004 /* Linux-USB "MIDI Gadget" */
85
86 /* string IDs are assigned dynamically */
87
88 #define STRING_MANUFACTURER_IDX 0
89 #define STRING_PRODUCT_IDX 1
90 #define STRING_DESCRIPTION_IDX 2
91
92 static struct usb_device_descriptor device_desc = {
93 .bLength = USB_DT_DEVICE_SIZE,
94 .bDescriptorType = USB_DT_DEVICE,
95 .bcdUSB = __constant_cpu_to_le16(0x0200),
96 .bDeviceClass = USB_CLASS_PER_INTERFACE,
97 .idVendor = __constant_cpu_to_le16(DRIVER_VENDOR_NUM),
98 .idProduct = __constant_cpu_to_le16(DRIVER_PRODUCT_NUM),
99 /* .iManufacturer = DYNAMIC */
100 /* .iProduct = DYNAMIC */
101 .bNumConfigurations = 1,
102 };
103
104 static struct usb_string strings_dev[] = {
105 [STRING_MANUFACTURER_IDX].s = "Grey Innovation",
106 [STRING_PRODUCT_IDX].s = "MIDI Gadget",
107 [STRING_DESCRIPTION_IDX].s = "MIDI",
108 { } /* end of list */
109 };
110
111 static struct usb_gadget_strings stringtab_dev = {
112 .language = 0x0409, /* en-us */
113 .strings = strings_dev,
114 };
115
116 static struct usb_gadget_strings *dev_strings[] = {
117 &stringtab_dev,
118 NULL,
119 };
120
midi_unbind(struct usb_composite_dev * dev)121 static int __exit midi_unbind(struct usb_composite_dev *dev)
122 {
123 return 0;
124 }
125
126 static struct usb_configuration midi_config = {
127 .label = "MIDI Gadget",
128 .bConfigurationValue = 1,
129 /* .iConfiguration = DYNAMIC */
130 .bmAttributes = USB_CONFIG_ATT_ONE,
131 .bMaxPower = CONFIG_USB_GADGET_VBUS_DRAW / 2,
132 };
133
midi_bind_config(struct usb_configuration * c)134 static int __init midi_bind_config(struct usb_configuration *c)
135 {
136 return f_midi_bind_config(c, index, id,
137 in_ports, out_ports,
138 buflen, qlen);
139 }
140
midi_bind(struct usb_composite_dev * cdev)141 static int __init midi_bind(struct usb_composite_dev *cdev)
142 {
143 struct usb_gadget *gadget = cdev->gadget;
144 int gcnum, status;
145
146 status = usb_string_id(cdev);
147 if (status < 0)
148 return status;
149 strings_dev[STRING_MANUFACTURER_IDX].id = status;
150 device_desc.iManufacturer = status;
151
152 status = usb_string_id(cdev);
153 if (status < 0)
154 return status;
155 strings_dev[STRING_PRODUCT_IDX].id = status;
156 device_desc.iProduct = status;
157
158 /* config description */
159 status = usb_string_id(cdev);
160 if (status < 0)
161 return status;
162 strings_dev[STRING_DESCRIPTION_IDX].id = status;
163
164 midi_config.iConfiguration = status;
165
166 gcnum = usb_gadget_controller_number(gadget);
167 if (gcnum < 0) {
168 /* gmidi is so simple (no altsettings) that
169 * it SHOULD NOT have problems with bulk-capable hardware.
170 * so warn about unrecognized controllers, don't panic.
171 */
172 pr_warning("%s: controller '%s' not recognized\n",
173 __func__, gadget->name);
174 device_desc.bcdDevice = cpu_to_le16(0x9999);
175 } else {
176 device_desc.bcdDevice = cpu_to_le16(0x0200 + gcnum);
177 }
178
179 status = usb_add_config(cdev, &midi_config, midi_bind_config);
180 if (status < 0)
181 return status;
182
183 pr_info("%s\n", longname);
184 return 0;
185 }
186
187 static struct usb_composite_driver midi_driver = {
188 .name = (char *) longname,
189 .dev = &device_desc,
190 .strings = dev_strings,
191 .max_speed = USB_SPEED_HIGH,
192 .unbind = __exit_p(midi_unbind),
193 };
194
midi_init(void)195 static int __init midi_init(void)
196 {
197 return usb_composite_probe(&midi_driver, midi_bind);
198 }
199 module_init(midi_init);
200
midi_cleanup(void)201 static void __exit midi_cleanup(void)
202 {
203 usb_composite_unregister(&midi_driver);
204 }
205 module_exit(midi_cleanup);
206
207