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
  35 MODULE_AUTHOR("Ben Williamson");
  36 MODULE_LICENSE("GPL v2");
  37
  38 static const char longname[] = "MIDI Gadget";
  39
  40 USB_GADGET_COMPOSITE_OPTIONS();
  41
  42 static int index = SNDRV_DEFAULT_IDX1;
  43 module_param(index, int, S_IRUGO);
  44 MODULE_PARM_DESC(index, "Index value for the USB MIDI Gadget adapter.");
  45
  46 static char *id = SNDRV_DEFAULT_STR1;
  47 module_param(id, charp, S_IRUGO);
  48 MODULE_PARM_DESC(id, "ID string for the USB MIDI Gadget adapter.");
  49
  50 static unsigned int buflen = 512;
  51 module_param(buflen, uint, S_IRUGO);
  52 MODULE_PARM_DESC(buflen, "MIDI buffer length");
  53
  54 static unsigned int qlen = 32;
  55 module_param(qlen, uint, S_IRUGO);
  56 MODULE_PARM_DESC(qlen, "USB read and write request queue length");
  57
  58 static unsigned int in_ports = 1;
  59 module_param(in_ports, uint, S_IRUGO);
  60 MODULE_PARM_DESC(in_ports, "Number of MIDI input ports");
  61
  62 static unsigned int out_ports = 1;
  63 module_param(out_ports, uint, S_IRUGO);
  64 MODULE_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
  78 static 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
  90 static 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
  98 static struct usb_gadget_strings stringtab_dev = {
  99         .language       = 0x0409,       /* en-us */
 100         .strings        = strings_dev,
 101 };
 102
 103 static struct usb_gadget_strings *dev_strings[] = {
 104         &stringtab_dev,
 105         NULL,
 106 };
 107
 108 static struct usb_function_instance *fi_midi;
 109 static struct usb_function *f_midi;
 110
 111 static 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
 118 static 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
 126 static 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
 143 static 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;
 173 put:
 174         usb_put_function_instance(fi_midi);
 175         return status;
 176 }
 177
 178 static 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
 187 module_usb_composite_driver(midi_driver);