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
 48MODULE_AUTHOR("Ben Williamson");
 49MODULE_LICENSE("GPL v2");
 50
 51static const char shortname[] = "g_midi";
 52static const char longname[] = "MIDI Gadget";
 53
 54static int index = SNDRV_DEFAULT_IDX1;
 55module_param(index, int, S_IRUGO);
 56MODULE_PARM_DESC(index, "Index value for the USB MIDI Gadget adapter.");
 57
 58static char *id = SNDRV_DEFAULT_STR1;
 59module_param(id, charp, S_IRUGO);
 60MODULE_PARM_DESC(id, "ID string for the USB MIDI Gadget adapter.");
 61
 62static unsigned int buflen = 256;
 63module_param(buflen, uint, S_IRUGO);
 64MODULE_PARM_DESC(buflen, "MIDI buffer length");
 65
 66static unsigned int qlen = 32;
 67module_param(qlen, uint, S_IRUGO);
 68MODULE_PARM_DESC(qlen, "USB read request queue length");
 69
 70static unsigned int in_ports = 1;
 71module_param(in_ports, uint, S_IRUGO);
 72MODULE_PARM_DESC(in_ports, "Number of MIDI input ports");
 73
 74static unsigned int out_ports = 1;
 75module_param(out_ports, uint, S_IRUGO);
 76MODULE_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
 92static 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
104static 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
111static struct usb_gadget_strings stringtab_dev = {
112	.language	= 0x0409,	/* en-us */
113	.strings	= strings_dev,
114};
115
116static struct usb_gadget_strings *dev_strings[] = {
117	&stringtab_dev,
118	NULL,
119};
120
121static int __exit midi_unbind(struct usb_composite_dev *dev)
122{
123	return 0;
124}
125
126static 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
134static 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
141static 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
187static 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
195static int __init midi_init(void)
196{
197	return usb_composite_probe(&midi_driver, midi_bind);
198}
199module_init(midi_init);
200
201static void __exit midi_cleanup(void)
202{
203	usb_composite_unregister(&midi_driver);
204}
205module_exit(midi_cleanup);
206