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Definitions for the USB audio driver files


This file is part of Open Sound System.

Copyright (C) 4Front Technologies 1996-2008.

This this source file is released under GPL v2 license (no other versions). See the COPYING file included in the main directory of this source distribution for the license terms and conditions.

#ifndef __OSUSB_H_
#define __OSUSB_H_

#include "udi.h"
#include "midi_core.h"

#define CS_DEVICE                0x21
#define CS_CONFIG                0x22
#define CS_STRING                0x23
#define CS_INTERFACE             0x24
#define CS_ENDPOINT              0x25

#define AC_HEADER		0x01
#define AC_INPUT_TERMINAL	0x02
#define AC_MIXER_UNIT		0x04
#define AC_SELECTOR_UNIT	0x05
#define AC_FEATURE_UNIT		0x06
#define AC_EXTENSION_UNIT	0x08

#define AS_GENERAL		0x01
#define AS_FORMAT_TYPE		0x02

#define SET_CUR    0x01
#define SET_MEM    0x05
#define GET_CUR    0x81
#define GET_MIN    0x82
#define GET_MAX    0x83
#define GET_RES    0x84
#define GET_MEM    0x85
#define GET_STAT   0xff

#define USB_RECIP_MASK                  0x1f
#define USB_RECIP_DEVICE                0x00
#define USB_RECIP_INTERFACE             0x01
#define USB_RECIP_ENDPOINT              0x02
#define USB_RECIP_OTHER                 0x03
#define USB_VENDOR_REQUEST		0x40

#define USB_TYPE_CLASS                  0x20

Unit types

Note that TY_OUTPUT is actually PCM input and TY_INPUT is actually PCM output. Unit types are defined as seen as the USB control interface. Input terminals listen to the output streaming interfases and output terminals feed the input streaming interfaces. Confusing it is.

#define TY_INPUT		0
#define TY_OUTPUT		1
#define TY_MIXER		2
#define TY_SELECT		3
#define TY_FEAT			4
#define TY_PROC			5
#define TY_EXT			6
// Remember to inclease size of devc->unit_counters[] if adding more unit types

#define USBCLASS_AUDIO			1
#define USBCLASS_HID			3

#define MAX_IFACE 10

typedef struct
  int num;
  int typ;			// TY_*
  int subtyp;
  char name[16];
  unsigned char *desc;
  int desclen;
  int mixnum;
  int target;
  int source;
  int ctl_avail;
  int control_count;
  int channels;
  int chmask;
} usb_audio_unit_t;

#define MAX_UNIT 40
#define MAX_CONTROLS	100
#define MAX_PORTC	8	/* Max audio streaming interfaces per device */
#define MAX_MIDIC	16	/* Max MIDI streaming interfaces per device */

typedef struct
  usb_audio_unit_t *unit;
  int index;
  int flags;
  int min_ch, max_ch;
  int global;
  int chmask;
  int value;
  int min, max, scale;
  int exttype;
} usb_control_t;

typedef struct ossusb_devc ossusb_devc;

typedef struct
  ossusb_devc *devc;
  int disabled;
  int if_number;
  void *endpoint_desc, *orig_endpoint_desc;
  udi_endpoint_handle_t *endpoint_handle;
  int audio_dev;
  int open_mode;
  int permitted_modes;
  int prepared_modes;
  int stopping;

  int speed;
  int bytes_per_sample;
  int terminal_link;
  udi_usb_devc *usbdev;
  int num_settings;
  int act_setting;

#define NR_DATAPIPES	2
  udi_usb_request_t *datapipe[NR_DATAPIPES];
  int curr_datapipe;
  int fragment_size;		/* Bytes per (1ms) USB tick */
  int overflow_samples, overflow_size;
  int convert_3byte;
  int pipeline_delay;
  unsigned char *tmp_buf[2];
  int use_tmpbuf;
  oss_dma_handle_t tmpbuf_dma_handle[2];
} ossusb_portc;

typedef struct
  struct ossusb_devc *devc;
  oss_device_t *osdev;
  udi_usb_devc *usbdev;

  void *in_endpoint_desc, *out_endpoint_desc;
  udi_endpoint_handle_t *in_endpoint_handle, *out_endpoint_handle;
  int portnum;
  int midi_dev;
  int open_mode;
  // int output_endpoint;
  oss_midi_inputbyte_t midi_input_intr;
  oss_midi_outputintr_t midi_output_intr;
} ossusb_midic;

typedef void *(*special_driver_t) (ossusb_devc * devc);
typedef void (*special_unload_t) (void *devc);

struct ossusb_devc
  special_unload_t unload_func;
  oss_device_t *osdev;
  oss_device_t *main_osdev;
  oss_mutex_t mutex;
  int num_interfaces;
  udi_usb_devc *usbdev[MAX_IFACE], *last_usbdev;
  int inum[MAX_IFACE];
  int vendor, product;
  char *dev_name, devpath[32];
  int nports;
  int disabled;


  usb_audio_unit_t units[MAX_UNIT];
  int nunits;
  char unit_counters[7];	// For TY_* identifiers

Mixer stuff

  int mixer_dev;
  void *mixer_usbdev;
  int devmask, recmask, stereodevs, recsrc;

  int rec_unit;
  int num_recdevs;
  int recdevs[32];

  int *levels;

  usb_control_t controls[MAX_CONTROLS];
  int ncontrols;

/* Audio stuff */
  int num_audio_engines, num_inputs, num_outputs;
  ossusb_portc portc[MAX_PORTC];

/* MIDI stuff */
  int num_mididevs;
  ossusb_midic midic[MAX_MIDIC];

  unsigned char *playbuf;
  oss_dma_handle_t playbuf_dma_handle;
  udi_usb_request_t *output_pipe;
  int output_busy;
#define Q_MAX 4096
  unsigned char queue[Q_MAX];
  int q_nbytes;

  unsigned char *recbuf;
  oss_dma_handle_t recbuf_dma_handle;
  udi_usb_request_t *input_pipe;
  udi_endpoint_handle_t *input_endpoint_handle;

extern int usb_trace, usb_quiet;

#define UDB(x) {if (usb_trace) x;}

extern ossusb_devc *ossusb_init_audiostream (ossusb_devc * devc,
					     udi_usb_devc * usbdev, int inum,
					     int reinit);
extern ossusb_devc *ossusb_init_midistream (ossusb_devc * devc,
					    udi_usb_devc * usbdev, int inum,
					    int reinit);
extern void ossusb_disconnect_midistream (ossusb_devc * devc);
extern void ossusb_dump_desc (unsigned char *desc, int cfg_len);
extern unsigned int ossusb_get_int (unsigned char *p, int nbytes);
extern int ossusb_change_altsetting (int dev, int ctrl, unsigned int cmd,
				     int value);
extern void ossusb_create_altset_control(int dev, int portc_num, int nalt, char *name);

Copyright (C) 4Front Technologies, 2007. All rights reserved.

Back to index OSS web site

Copyright (C) 4Front Technologies, 2007. All rights reserved.
Back to index OSS web site