LXR linux/drivers/usb/gadget/legacy/gmidi.c

   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/module.h>
  25
  26#include <sound/initval.h>
  27
  28#include <linux/usb/composite.h>
  29#include <linux/usb/gadget.h>
  30
  31#include "u_midi.h"
  32
  33/*-------------------------------------------------------------------------*/
  34
  35MODULE_AUTHOR("Ben Williamson");
  36MODULE_LICENSE("GPL v2");
  37
  38static const char longname[] = "MIDI Gadget";
  39
  40USB_GADGET_COMPOSITE_OPTIONS();
  41
  42static int index = SNDRV_DEFAULT_IDX1;
  43module_param(index, int, S_IRUGO);
  44MODULE_PARM_DESC(index, "Index value for the USB MIDI Gadget adapter.");
  45
  46static char *id = SNDRV_DEFAULT_STR1;
  47module_param(id, charp, S_IRUGO);
  48MODULE_PARM_DESC(id, "ID string for the USB MIDI Gadget adapter.");
  49
  50static unsigned int buflen = 256;
  51module_param(buflen, uint, S_IRUGO);
  52MODULE_PARM_DESC(buflen, "MIDI buffer length");
  53
  54static unsigned int qlen = 32;
  55module_param(qlen, uint, S_IRUGO);
  56MODULE_PARM_DESC(qlen, "USB read and write request queue length");
  57
  58static unsigned int in_ports = 1;
  59module_param(in_ports, uint, S_IRUGO);
  60MODULE_PARM_DESC(in_ports, "Number of MIDI input ports");
  61
  62static unsigned int out_ports = 1;
  63module_param(out_ports, uint, S_IRUGO);
  64MODULE_PARM_DESC(out_ports, "Number of MIDI output ports");
  65
  66/* Thanks to Grey Innovation for donating this product ID.
  67 *
  68 * DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
  69 * Instead:  allocate your own, using normal USB-IF procedures.
  70 */
  71#define DRIVER_VENDOR_NUM       0x17b3          /* Grey Innovation */
  72#define DRIVER_PRODUCT_NUM      0x0004          /* Linux-USB "MIDI Gadget" */
  73
  74/* string IDs are assigned dynamically */
  75
  76#define STRING_DESCRIPTION_IDX          USB_GADGET_FIRST_AVAIL_IDX
  77
  78static struct usb_device_descriptor device_desc = {
  79        .bLength =              USB_DT_DEVICE_SIZE,
  80        .bDescriptorType =      USB_DT_DEVICE,
  81        /* .bcdUSB = DYNAMIC */
  82        .bDeviceClass =         USB_CLASS_PER_INTERFACE,
  83        .idVendor =             cpu_to_le16(DRIVER_VENDOR_NUM),
  84        .idProduct =            cpu_to_le16(DRIVER_PRODUCT_NUM),
  85        /* .iManufacturer =     DYNAMIC */
  86        /* .iProduct =          DYNAMIC */
  87        .bNumConfigurations =   1,
  88};
  89
  90static struct usb_string strings_dev[] = {
  91        [USB_GADGET_MANUFACTURER_IDX].s = "Grey Innovation",
  92        [USB_GADGET_PRODUCT_IDX].s      = "MIDI Gadget",
  93        [USB_GADGET_SERIAL_IDX].s       = "",
  94        [STRING_DESCRIPTION_IDX].s      = "MIDI",
  95        {  } /* end of list */
  96};
  97
  98static struct usb_gadget_strings stringtab_dev = {
  99        .language       = 0x0409,       /* en-us */
 100        .strings        = strings_dev,
 101};
 102
 103static struct usb_gadget_strings *dev_strings[] = {
 104        &stringtab_dev,
 105        NULL,
 106};
 107
 108static struct usb_function_instance *fi_midi;
 109static struct usb_function *f_midi;
 110
 111static int midi_unbind(struct usb_composite_dev *dev)
 112{
 113        usb_put_function(f_midi);
 114        usb_put_function_instance(fi_midi);
 115        return 0;
 116}
 117
 118static struct usb_configuration midi_config = {
 119        .label          = "MIDI Gadget",
 120        .bConfigurationValue = 1,
 121        /* .iConfiguration = DYNAMIC */
 122        .bmAttributes   = USB_CONFIG_ATT_ONE,
 123        .MaxPower       = CONFIG_USB_GADGET_VBUS_DRAW,
 124};
 125
 126static int midi_bind_config(struct usb_configuration *c)
 127{
 128        int status;
 129
 130        f_midi = usb_get_function(fi_midi);
 131        if (IS_ERR(f_midi))
 132                return PTR_ERR(f_midi);
 133
 134        status = usb_add_function(c, f_midi);
 135        if (status < 0) {
 136                usb_put_function(f_midi);
 137                return status;
 138        }
 139
 140        return 0;
 141}
 142
 143static int midi_bind(struct usb_composite_dev *cdev)
 144{
 145        struct f_midi_opts *midi_opts;
 146        int status;
 147
 148        fi_midi = usb_get_function_instance("midi");
 149        if (IS_ERR(fi_midi))
 150                return PTR_ERR(fi_midi);
 151
 152        midi_opts = container_of(fi_midi, struct f_midi_opts, func_inst);
 153        midi_opts->index = index;
 154        midi_opts->id = id;
 155        midi_opts->in_ports = in_ports;
 156        midi_opts->out_ports = out_ports;
 157        midi_opts->buflen = buflen;
 158        midi_opts->qlen = qlen;
 159
 160        status = usb_string_ids_tab(cdev, strings_dev);
 161        if (status < 0)
 162                goto put;
 163        device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 164        device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 165        midi_config.iConfiguration = strings_dev[STRING_DESCRIPTION_IDX].id;
 166
 167        status = usb_add_config(cdev, &midi_config, midi_bind_config);
 168        if (status < 0)
 169                goto put;
 170        usb_composite_overwrite_options(cdev, &coverwrite);
 171        pr_info("%s\n", longname);
 172        return 0;
 173put:
 174        usb_put_function_instance(fi_midi);
 175        return status;
 176}
 177
 178static struct usb_composite_driver midi_driver = {
 179        .name           = (char *) longname,
 180        .dev            = &device_desc,
 181        .strings        = dev_strings,
 182        .max_speed      = USB_SPEED_HIGH,
 183        .bind           = midi_bind,
 184        .unbind         = midi_unbind,
 185};
 186
 187module_usb_composite_driver(midi_driver);
 188