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