1 // SPDX-License-Identifier: GPL-2.0
3 * gmidi.c -- USB MIDI Gadget Driver
5 * Copyright (C) 2006 Thumtronics Pty Ltd.
6 * Developed for Thumtronics by Grey Innovation
7 * Ben Williamson <ben.williamson@greyinnovation.com>
9 * This code is based in part on:
11 * Gadget Zero driver, Copyright (C) 2003-2004 David Brownell.
12 * USB Audio driver, Copyright (C) 2002 by Takashi Iwai.
13 * USB MIDI driver, Copyright (C) 2002-2005 Clemens Ladisch.
15 * Refer to the USB Device Class Definition for MIDI Devices:
16 * http://www.usb.org/developers/devclass_docs/midi10.pdf
19 /* #define VERBOSE_DEBUG */
21 #include <linux/kernel.h>
22 #include <linux/module.h>
24 #include <sound/initval.h>
26 #include <linux/usb/composite.h>
27 #include <linux/usb/gadget.h>
31 /*-------------------------------------------------------------------------*/
33 MODULE_AUTHOR("Ben Williamson");
34 MODULE_LICENSE("GPL v2");
36 static const char longname
[] = "MIDI Gadget";
38 USB_GADGET_COMPOSITE_OPTIONS();
40 static int index
= SNDRV_DEFAULT_IDX1
;
41 module_param(index
, int, S_IRUGO
);
42 MODULE_PARM_DESC(index
, "Index value for the USB MIDI Gadget adapter.");
44 static char *id
= SNDRV_DEFAULT_STR1
;
45 module_param(id
, charp
, S_IRUGO
);
46 MODULE_PARM_DESC(id
, "ID string for the USB MIDI Gadget adapter.");
48 static unsigned int buflen
= 512;
49 module_param(buflen
, uint
, S_IRUGO
);
50 MODULE_PARM_DESC(buflen
, "MIDI buffer length");
52 static unsigned int qlen
= 32;
53 module_param(qlen
, uint
, S_IRUGO
);
54 MODULE_PARM_DESC(qlen
, "USB read and write request queue length");
56 static unsigned int in_ports
= 1;
57 module_param(in_ports
, uint
, S_IRUGO
);
58 MODULE_PARM_DESC(in_ports
, "Number of MIDI input ports");
60 static unsigned int out_ports
= 1;
61 module_param(out_ports
, uint
, S_IRUGO
);
62 MODULE_PARM_DESC(out_ports
, "Number of MIDI output ports");
64 /* Thanks to Grey Innovation for donating this product ID.
66 * DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!!
67 * Instead: allocate your own, using normal USB-IF procedures.
69 #define DRIVER_VENDOR_NUM 0x17b3 /* Grey Innovation */
70 #define DRIVER_PRODUCT_NUM 0x0004 /* Linux-USB "MIDI Gadget" */
72 /* string IDs are assigned dynamically */
74 #define STRING_DESCRIPTION_IDX USB_GADGET_FIRST_AVAIL_IDX
76 static struct usb_device_descriptor device_desc
= {
77 .bLength
= USB_DT_DEVICE_SIZE
,
78 .bDescriptorType
= USB_DT_DEVICE
,
79 /* .bcdUSB = DYNAMIC */
80 .bDeviceClass
= USB_CLASS_PER_INTERFACE
,
81 .idVendor
= cpu_to_le16(DRIVER_VENDOR_NUM
),
82 .idProduct
= cpu_to_le16(DRIVER_PRODUCT_NUM
),
83 /* .iManufacturer = DYNAMIC */
84 /* .iProduct = DYNAMIC */
85 .bNumConfigurations
= 1,
88 static struct usb_string strings_dev
[] = {
89 [USB_GADGET_MANUFACTURER_IDX
].s
= "Grey Innovation",
90 [USB_GADGET_PRODUCT_IDX
].s
= "MIDI Gadget",
91 [USB_GADGET_SERIAL_IDX
].s
= "",
92 [STRING_DESCRIPTION_IDX
].s
= "MIDI",
96 static struct usb_gadget_strings stringtab_dev
= {
97 .language
= 0x0409, /* en-us */
98 .strings
= strings_dev
,
101 static struct usb_gadget_strings
*dev_strings
[] = {
106 static struct usb_function_instance
*fi_midi
;
107 static struct usb_function
*f_midi
;
109 static int midi_unbind(struct usb_composite_dev
*dev
)
111 usb_put_function(f_midi
);
112 usb_put_function_instance(fi_midi
);
116 static struct usb_configuration midi_config
= {
117 .label
= "MIDI Gadget",
118 .bConfigurationValue
= 1,
119 /* .iConfiguration = DYNAMIC */
120 .bmAttributes
= USB_CONFIG_ATT_ONE
,
121 .MaxPower
= CONFIG_USB_GADGET_VBUS_DRAW
,
124 static int midi_bind_config(struct usb_configuration
*c
)
128 f_midi
= usb_get_function(fi_midi
);
130 return PTR_ERR(f_midi
);
132 status
= usb_add_function(c
, f_midi
);
134 usb_put_function(f_midi
);
141 static int midi_bind(struct usb_composite_dev
*cdev
)
143 struct f_midi_opts
*midi_opts
;
146 fi_midi
= usb_get_function_instance("midi");
148 return PTR_ERR(fi_midi
);
150 midi_opts
= container_of(fi_midi
, struct f_midi_opts
, func_inst
);
151 midi_opts
->index
= index
;
153 midi_opts
->in_ports
= in_ports
;
154 midi_opts
->out_ports
= out_ports
;
155 midi_opts
->buflen
= buflen
;
156 midi_opts
->qlen
= qlen
;
158 status
= usb_string_ids_tab(cdev
, strings_dev
);
161 device_desc
.iManufacturer
= strings_dev
[USB_GADGET_MANUFACTURER_IDX
].id
;
162 device_desc
.iProduct
= strings_dev
[USB_GADGET_PRODUCT_IDX
].id
;
163 midi_config
.iConfiguration
= strings_dev
[STRING_DESCRIPTION_IDX
].id
;
165 status
= usb_add_config(cdev
, &midi_config
, midi_bind_config
);
168 usb_composite_overwrite_options(cdev
, &coverwrite
);
169 pr_info("%s\n", longname
);
172 usb_put_function_instance(fi_midi
);
176 static struct usb_composite_driver midi_driver
= {
177 .name
= (char *) longname
,
179 .strings
= dev_strings
,
180 .max_speed
= USB_SPEED_HIGH
,
182 .unbind
= midi_unbind
,
185 module_usb_composite_driver(midi_driver
);