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/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 "u_midi.h"
  41
  42 /*-------------------------------------------------------------------------*/
  43
  44 MODULE_AUTHOR("Ben Williamson");
  45 MODULE_LICENSE("GPL v2");
  46
  47 static const char shortname[] = "g_midi";
  48 static const char longname[] = "MIDI Gadget";
  49
  50 USB_GADGET_COMPOSITE_OPTIONS();
  51
  52 static int index = SNDRV_DEFAULT_IDX1;
  53 module_param(index, int, S_IRUGO);
  54 MODULE_PARM_DESC(index, "Index value for the USB MIDI Gadget adapter.");
  55
  56 static char *id = SNDRV_DEFAULT_STR1;
  57 module_param(id, charp, S_IRUGO);
  58 MODULE_PARM_DESC(id, "ID string for the USB MIDI Gadget adapter.");
  59
  60 static unsigned int buflen = 256;
  61 module_param(buflen, uint, S_IRUGO);
  62 MODULE_PARM_DESC(buflen, "MIDI buffer length");
  63
  64 static unsigned int qlen = 32;
  65 module_param(qlen, uint, S_IRUGO);
  66 MODULE_PARM_DESC(qlen, "USB read request queue length");
  67
  68 static unsigned int in_ports = 1;
  69 module_param(in_ports, uint, S_IRUGO);
  70 MODULE_PARM_DESC(in_ports, "Number of MIDI input ports");
  71
  72 static unsigned int out_ports = 1;
  73 module_param(out_ports, uint, S_IRUGO);
  74 MODULE_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
  88 static 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
 100 static 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
 108 static struct usb_gadget_strings stringtab_dev = {
 109         .language       = 0x0409,       /* en-us */
 110         .strings        = strings_dev,
 111 };
 112
 113 static struct usb_gadget_strings *dev_strings[] = {
 114         &stringtab_dev,
 115         NULL,
 116 };
 117
 118 static struct usb_function_instance *fi_midi;
 119 static struct usb_function *f_midi;
 120
 121 static int __exit midi_unbind(struct usb_composite_dev *dev)
 122 {
 123         usb_put_function(f_midi);
 124         usb_put_function_instance(fi_midi);
 125         return 0;
 126 }
 127
 128 static struct usb_configuration midi_config = {
 129         .label          = "MIDI Gadget",
 130         .bConfigurationValue = 1,
 131         /* .iConfiguration = DYNAMIC */
 132         .bmAttributes   = USB_CONFIG_ATT_ONE,
 133         .MaxPower       = CONFIG_USB_GADGET_VBUS_DRAW,
 134 };
 135
 136 static int __init midi_bind_config(struct usb_configuration *c)
 137 {
 138         int status;
 139
 140         f_midi = usb_get_function(fi_midi);
 141         if (IS_ERR(f_midi))
 142                 return PTR_ERR(f_midi);
 143
 144         status = usb_add_function(c, f_midi);
 145         if (status < 0) {
 146                 usb_put_function(f_midi);
 147                 return status;
 148         }
 149
 150         return 0;
 151 }
 152
 153 static int __init midi_bind(struct usb_composite_dev *cdev)
 154 {
 155         struct f_midi_opts *midi_opts;
 156         int status;
 157
 158         fi_midi = usb_get_function_instance("midi");
 159         if (IS_ERR(fi_midi))
 160                 return PTR_ERR(fi_midi);
 161
 162         midi_opts = container_of(fi_midi, struct f_midi_opts, func_inst);
 163         midi_opts->index = index;
 164         midi_opts->id = id;
 165         midi_opts->in_ports = in_ports;
 166         midi_opts->out_ports = out_ports;
 167         midi_opts->buflen = buflen;
 168         midi_opts->qlen = qlen;
 169
 170         status = usb_string_ids_tab(cdev, strings_dev);
 171         if (status < 0)
 172                 goto put;
 173         device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 174         device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 175         midi_config.iConfiguration = strings_dev[STRING_DESCRIPTION_IDX].id;
 176
 177         status = usb_add_config(cdev, &midi_config, midi_bind_config);
 178         if (status < 0)
 179                 goto put;
 180         usb_composite_overwrite_options(cdev, &coverwrite);
 181         pr_info("%s\n", longname);
 182         return 0;
 183 put:
 184         usb_put_function_instance(fi_midi);
 185         return status;
 186 }
 187
 188 static __refdata struct usb_composite_driver midi_driver = {
 189         .name           = (char *) longname,
 190         .dev            = &device_desc,
 191         .strings        = dev_strings,
 192         .max_speed      = USB_SPEED_HIGH,
 193         .bind           = midi_bind,
 194         .unbind         = __exit_p(midi_unbind),
 195 };
 196
 197 module_usb_composite_driver(midi_driver);