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/module.h>
 26#include <linux/device.h>
 27
 28#include <sound/core.h>
 29#include <sound/initval.h>
 30#include <sound/rawmidi.h>
 31
 32#include <linux/usb/ch9.h>
 33#include <linux/usb/composite.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 "f_midi.c"
 41
 42/*-------------------------------------------------------------------------*/
 43
 44MODULE_AUTHOR("Ben Williamson");
 45MODULE_LICENSE("GPL v2");
 46
 47static const char shortname[] = "g_midi";
 48static const char longname[] = "MIDI Gadget";
 49
 50USB_GADGET_COMPOSITE_OPTIONS();
 51
 52static int index = SNDRV_DEFAULT_IDX1;
 53module_param(index, int, S_IRUGO);
 54MODULE_PARM_DESC(index, "Index value for the USB MIDI Gadget adapter.");
 55
 56static char *id = SNDRV_DEFAULT_STR1;
 57module_param(id, charp, S_IRUGO);
 58MODULE_PARM_DESC(id, "ID string for the USB MIDI Gadget adapter.");
 59
 60static unsigned int buflen = 256;
 61module_param(buflen, uint, S_IRUGO);
 62MODULE_PARM_DESC(buflen, "MIDI buffer length");
 63
 64static unsigned int qlen = 32;
 65module_param(qlen, uint, S_IRUGO);
 66MODULE_PARM_DESC(qlen, "USB read request queue length");
 67
 68static unsigned int in_ports = 1;
 69module_param(in_ports, uint, S_IRUGO);
 70MODULE_PARM_DESC(in_ports, "Number of MIDI input ports");
 71
 72static unsigned int out_ports = 1;
 73module_param(out_ports, uint, S_IRUGO);
 74MODULE_PARM_DESC(out_ports, "Number of MIDI output ports");
 75
 76/* Thanks to Grey Innovation for donating this product ID.
 77 *
 78 * DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
 79 * Instead:  allocate your own, using normal USB-IF procedures.
 80 */
 81#define DRIVER_VENDOR_NUM	0x17b3		/* Grey Innovation */
 82#define DRIVER_PRODUCT_NUM	0x0004		/* Linux-USB "MIDI Gadget" */
 83
 84/* string IDs are assigned dynamically */
 85
 86#define STRING_DESCRIPTION_IDX		USB_GADGET_FIRST_AVAIL_IDX
 87
 88static struct usb_device_descriptor device_desc = {
 89	.bLength =		USB_DT_DEVICE_SIZE,
 90	.bDescriptorType =	USB_DT_DEVICE,
 91	.bcdUSB =		__constant_cpu_to_le16(0x0200),
 92	.bDeviceClass =		USB_CLASS_PER_INTERFACE,
 93	.idVendor =		__constant_cpu_to_le16(DRIVER_VENDOR_NUM),
 94	.idProduct =		__constant_cpu_to_le16(DRIVER_PRODUCT_NUM),
 95	/* .iManufacturer =	DYNAMIC */
 96	/* .iProduct =		DYNAMIC */
 97	.bNumConfigurations =	1,
 98};
 99
100static struct usb_string strings_dev[] = {
101	[USB_GADGET_MANUFACTURER_IDX].s	= "Grey Innovation",
102	[USB_GADGET_PRODUCT_IDX].s	= "MIDI Gadget",
103	[USB_GADGET_SERIAL_IDX].s	= "",
104	[STRING_DESCRIPTION_IDX].s	= "MIDI",
105	{  } /* end of list */
106};
107
108static struct usb_gadget_strings stringtab_dev = {
109	.language	= 0x0409,	/* en-us */
110	.strings	= strings_dev,
111};
112
113static struct usb_gadget_strings *dev_strings[] = {
114	&stringtab_dev,
115	NULL,
116};
117
118static int __exit midi_unbind(struct usb_composite_dev *dev)
119{
120	return 0;
121}
122
123static struct usb_configuration midi_config = {
124	.label		= "MIDI Gadget",
125	.bConfigurationValue = 1,
126	/* .iConfiguration = DYNAMIC */
127	.bmAttributes	= USB_CONFIG_ATT_ONE,
128	.MaxPower	= CONFIG_USB_GADGET_VBUS_DRAW,
129};
130
131static int __init midi_bind_config(struct usb_configuration *c)
132{
133	return f_midi_bind_config(c, index, id,
134				  in_ports, out_ports,
135				  buflen, qlen);
136}
137
138static int __init midi_bind(struct usb_composite_dev *cdev)
139{
140	int status;
141
142	status = usb_string_ids_tab(cdev, strings_dev);
143	if (status < 0)
144		return status;
145	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
146	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
147	midi_config.iConfiguration = strings_dev[STRING_DESCRIPTION_IDX].id;
148
149	status = usb_add_config(cdev, &midi_config, midi_bind_config);
150	if (status < 0)
151		return status;
152	usb_composite_overwrite_options(cdev, &coverwrite);
153	pr_info("%s\n", longname);
154	return 0;
155}
156
157static __refdata struct usb_composite_driver midi_driver = {
158	.name		= (char *) longname,
159	.dev		= &device_desc,
160	.strings	= dev_strings,
161	.max_speed	= USB_SPEED_HIGH,
162	.bind		= midi_bind,
163	.unbind		= __exit_p(midi_unbind),
164};
165
166static int __init midi_init(void)
167{
168	return usb_composite_probe(&midi_driver);
169}
170module_init(midi_init);
171
172static void __exit midi_cleanup(void)
173{
174	usb_composite_unregister(&midi_driver);
175}
176module_exit(midi_cleanup);
177