linux-zen-server/sound/firewire/cmp.h

54 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef SOUND_FIREWIRE_CMP_H_INCLUDED
#define SOUND_FIREWIRE_CMP_H_INCLUDED
#include <linux/mutex.h>
#include <linux/types.h>
#include "iso-resources.h"
struct fw_unit;
enum cmp_direction {
CMP_INPUT = 0,
CMP_OUTPUT,
};
/**
* struct cmp_connection - manages an isochronous connection to a device
* @speed: the connection's actual speed
*
* This structure manages (using CMP) an isochronous stream between the local
* computer and a device's input plug (iPCR) and output plug (oPCR).
*
* There is no corresponding oPCR created on the local computer, so it is not
* possible to overlay connections on top of this one.
*/
struct cmp_connection {
int speed;
/* private: */
bool connected;
struct mutex mutex;
struct fw_iso_resources resources;
__be32 last_pcr_value;
unsigned int pcr_index;
unsigned int max_speed;
enum cmp_direction direction;
};
int cmp_connection_init(struct cmp_connection *connection,
struct fw_unit *unit,
enum cmp_direction direction,
unsigned int pcr_index);
int cmp_connection_check_used(struct cmp_connection *connection, bool *used);
void cmp_connection_destroy(struct cmp_connection *connection);
int cmp_connection_reserve(struct cmp_connection *connection,
unsigned int max_payload);
void cmp_connection_release(struct cmp_connection *connection);
int cmp_connection_establish(struct cmp_connection *connection);
int cmp_connection_update(struct cmp_connection *connection);
void cmp_connection_break(struct cmp_connection *connection);
#endif