control.h

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#ifndef __SOUND_CONTROL_H
#define __SOUND_CONTROL_H

/*
 *  Header file for control interface
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <sound/asound.h>

#define snd_kcontrol_chip(kcontrol) ((kcontrol)->private_data)

struct snd_kcontrol;
typedef int (snd_kcontrol_info_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_info * uinfo);
typedef int (snd_kcontrol_get_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
typedef int (snd_kcontrol_put_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
typedef int (snd_kcontrol_tlv_rw_t)(struct snd_kcontrol *kcontrol,
                    int op_flag, /* 0=read,1=write,-1=command */
                    unsigned int size,
                    unsigned int __user *tlv);


struct snd_kcontrol_new {
    snd_ctl_elem_iface_t iface; /* interface identifier */
    unsigned int device;        /* device/client number */
    unsigned int subdevice;     /* subdevice (substream) number */
    const unsigned char *name;  /* ASCII name of item */
    unsigned int index;     /* index of item */
    unsigned int access;        /* access rights */
    unsigned int count;     /* count of same elements */
    snd_kcontrol_info_t *info;
    snd_kcontrol_get_t *get;
    snd_kcontrol_put_t *put;
    union {
        snd_kcontrol_tlv_rw_t *c;
        const unsigned int *p;
    } tlv;
    unsigned long private_value;
};

struct snd_kcontrol_volatile {
    struct snd_ctl_file *owner; /* locked */
    unsigned int access;    /* access rights */
};

struct snd_kcontrol {
    struct list_head list;      /* list of controls */
    struct snd_ctl_elem_id id;
    unsigned int count;     /* count of same elements */
    snd_kcontrol_info_t *info;
    snd_kcontrol_get_t *get;
    snd_kcontrol_put_t *put;
    union {
        snd_kcontrol_tlv_rw_t *c;
        const unsigned int *p;
    } tlv;
    unsigned long private_value;
    void *private_data;
    void (*private_free)(struct snd_kcontrol *kcontrol);
    struct snd_kcontrol_volatile vd[0]; /* volatile data */
};

#define snd_kcontrol(n) list_entry(n, struct snd_kcontrol, list)

struct snd_kctl_event {
    struct list_head list;  /* list of events */
    struct snd_ctl_elem_id id;
    unsigned int mask;
};

#define snd_kctl_event(n) list_entry(n, struct snd_kctl_event, list)

struct pid;

struct snd_ctl_file {
    struct list_head list;      /* list of all control files */
    struct snd_card *card;
    struct pid *pid;
    int prefer_pcm_subdevice;
    int prefer_rawmidi_subdevice;
    wait_queue_head_t change_sleep;
    spinlock_t read_lock;
    struct fasync_struct *fasync;
    int subscribed;         /* read interface is activated */
    struct list_head events;    /* waiting events for read */
};

#define snd_ctl_file(n) list_entry(n, struct snd_ctl_file, list)

typedef int (*snd_kctl_ioctl_func_t) (struct snd_card * card,
                      struct snd_ctl_file * control,
                      unsigned int cmd, unsigned long arg);

void snd_ctl_notify(struct snd_card * card, unsigned int mask, struct snd_ctl_elem_id * id);

struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new * kcontrolnew, void * private_data);
void snd_ctl_free_one(struct snd_kcontrol * kcontrol);
int snd_ctl_add(struct snd_card * card, struct snd_kcontrol * kcontrol);
int snd_ctl_remove(struct snd_card * card, struct snd_kcontrol * kcontrol);
int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol, bool add_on_replace);
int snd_ctl_remove_id(struct snd_card * card, struct snd_ctl_elem_id *id);
int snd_ctl_rename_id(struct snd_card * card, struct snd_ctl_elem_id *src_id, struct snd_ctl_elem_id *dst_id);
int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id,
            int active);
struct snd_kcontrol *snd_ctl_find_numid(struct snd_card * card, unsigned int numid);
struct snd_kcontrol *snd_ctl_find_id(struct snd_card * card, struct snd_ctl_elem_id *id);

int snd_ctl_create(struct snd_card *card);

int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn);
int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn);
#ifdef CONFIG_COMPAT
int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn);
int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn);
#else
#define snd_ctl_register_ioctl_compat(fcn)
#define snd_ctl_unregister_ioctl_compat(fcn)
#endif

static inline unsigned int snd_ctl_get_ioffnum(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
{
    return id->numid - kctl->id.numid;
}

static inline unsigned int snd_ctl_get_ioffidx(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
{
    return id->index - kctl->id.index;
}

static inline unsigned int snd_ctl_get_ioff(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
{
    if (id->numid) {
        return snd_ctl_get_ioffnum(kctl, id);
    } else {
        return snd_ctl_get_ioffidx(kctl, id);
    }
}

static inline struct snd_ctl_elem_id *snd_ctl_build_ioff(struct snd_ctl_elem_id *dst_id,
                            struct snd_kcontrol *src_kctl,
                            unsigned int offset)
{
    *dst_id = src_kctl->id;
    dst_id->index += offset;
    dst_id->numid += offset;
    return dst_id;
}

/*
 * Frequently used control callbacks/helpers
 */
int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
                  struct snd_ctl_elem_info *uinfo);
int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
                struct snd_ctl_elem_info *uinfo);
int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels,
              unsigned int items, const char *const names[]);

/*
 * virtual master control
 */
struct snd_kcontrol *snd_ctl_make_virtual_master(char *name,
                         const unsigned int *tlv);
int _snd_ctl_add_slave(struct snd_kcontrol *master, struct snd_kcontrol *slave,
               unsigned int flags);
/* optional flags for slave */
#define SND_CTL_SLAVE_NEED_UPDATE   (1 << 0)

static inline int
snd_ctl_add_slave(struct snd_kcontrol *master, struct snd_kcontrol *slave)
{
    return _snd_ctl_add_slave(master, slave, 0);
}

static inline int
snd_ctl_add_slave_uncached(struct snd_kcontrol *master,
               struct snd_kcontrol *slave)
{
    return _snd_ctl_add_slave(master, slave, SND_CTL_SLAVE_NEED_UPDATE);
}

int snd_ctl_add_vmaster_hook(struct snd_kcontrol *kctl,
                 void (*hook)(void *private_data, int),
                 void *private_data);
void snd_ctl_sync_vmaster_hook(struct snd_kcontrol *kctl);

/*
 * Helper functions for jack-detection controls
 */
struct snd_kcontrol *
snd_kctl_jack_new(const char *name, int idx, void *private_data);
void snd_kctl_jack_report(struct snd_card *card,
              struct snd_kcontrol *kctl, bool status);

#endif  /* __SOUND_CONTROL_H */