linux/include/sound/control.h
Richard Fitzgerald 08ea486a61
ALSA: control: Introduce snd_ctl_find_id_mixer_locked()
Adds wrapper function snd_ctl_find_id_mixer_locked(). This is
identical to snd_ctl_find_id_mixer() except that it can be called
from code that is already holding controls_rwsem.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Link: https://msgid.link/r/20240401100210.61277-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-04-02 15:54:47 +01:00

345 lines
12 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef __SOUND_CONTROL_H
#define __SOUND_CONTROL_H
/*
* Header file for control interface
* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
*/
#include <linux/wait.h>
#include <linux/nospec.h>
#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, /* SNDRV_CTL_TLV_OP_XXX */
unsigned int size,
unsigned int __user *tlv);
/* internal flag for skipping validations */
#ifdef CONFIG_SND_CTL_DEBUG
#define SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK (1 << 24)
#define snd_ctl_skip_validation(info) \
((info)->access & SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK)
#else
#define SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK 0
#define snd_ctl_skip_validation(info) true
#endif
/* kernel only - LED bits */
#define SNDRV_CTL_ELEM_ACCESS_LED_SHIFT 25
#define SNDRV_CTL_ELEM_ACCESS_LED_MASK (7<<25) /* kernel three bits - LED group */
#define SNDRV_CTL_ELEM_ACCESS_SPK_LED (1<<25) /* kernel speaker (output) LED flag */
#define SNDRV_CTL_ELEM_ACCESS_MIC_LED (2<<25) /* kernel microphone (input) LED flag */
enum {
SNDRV_CTL_TLV_OP_READ = 0,
SNDRV_CTL_TLV_OP_WRITE = 1,
SNDRV_CTL_TLV_OP_CMD = -1,
};
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 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[]; /* 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;
enum {
SND_CTL_SUBDEV_PCM,
SND_CTL_SUBDEV_RAWMIDI,
SND_CTL_SUBDEV_ITEMS,
};
struct snd_ctl_file {
struct list_head list; /* list of all control files */
struct snd_card *card;
struct pid *pid;
int preferred_subdevice[SND_CTL_SUBDEV_ITEMS];
wait_queue_head_t change_sleep;
spinlock_t read_lock;
struct snd_fasync *fasync;
int subscribed; /* read interface is activated */
struct list_head events; /* waiting events for read */
};
struct snd_ctl_layer_ops {
struct snd_ctl_layer_ops *next;
const char *module_name;
void (*lregister)(struct snd_card *card);
void (*ldisconnect)(struct snd_card *card);
void (*lnotify)(struct snd_card *card, unsigned int mask, struct snd_kcontrol *kctl, unsigned int ioff);
};
#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);
void snd_ctl_notify_one(struct snd_card * card, unsigned int mask, struct snd_kcontrol * kctl, unsigned int ioff);
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);
void snd_ctl_rename(struct snd_card *card, struct snd_kcontrol *kctl, const char *name);
int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id, int active);
struct snd_kcontrol *snd_ctl_find_numid_locked(struct snd_card *card, unsigned int numid);
struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid);
struct snd_kcontrol *snd_ctl_find_id_locked(struct snd_card *card, const struct snd_ctl_elem_id *id);
struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card, const struct snd_ctl_elem_id *id);
/**
* snd_ctl_find_id_mixer - find the control instance with the given name string
* @card: the card instance
* @name: the name string
*
* Finds the control instance with the given name and
* @SNDRV_CTL_ELEM_IFACE_MIXER. Other fields are set to zero.
*
* This is merely a wrapper to snd_ctl_find_id().
*
* Return: The pointer of the instance if found, or %NULL if not.
*/
static inline struct snd_kcontrol *
snd_ctl_find_id_mixer(struct snd_card *card, const char *name)
{
struct snd_ctl_elem_id id = {};
id.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
strscpy(id.name, name, sizeof(id.name));
return snd_ctl_find_id(card, &id);
}
/**
* snd_ctl_find_id_mixer_locked - find the control instance with the given name string
* @card: the card instance
* @name: the name string
*
* Finds the control instance with the given name and
* @SNDRV_CTL_ELEM_IFACE_MIXER. Other fields are set to zero.
*
* This is merely a wrapper to snd_ctl_find_id_locked().
* The caller must down card->controls_rwsem before calling this function.
*
* Return: The pointer of the instance if found, or %NULL if not.
*/
static inline struct snd_kcontrol *
snd_ctl_find_id_mixer_locked(struct snd_card *card, const char *name)
{
struct snd_ctl_elem_id id = {};
id.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
strscpy(id.name, name, sizeof(id.name));
return snd_ctl_find_id_locked(card, &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
int snd_ctl_request_layer(const char *module_name);
void snd_ctl_register_layer(struct snd_ctl_layer_ops *lops);
void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops *lops);
int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type);
static inline unsigned int snd_ctl_get_ioffnum(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
{
unsigned int ioff = id->numid - kctl->id.numid;
return array_index_nospec(ioff, kctl->count);
}
static inline unsigned int snd_ctl_get_ioffidx(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id)
{
unsigned int ioff = id->index - kctl->id.index;
return array_index_nospec(ioff, kctl->count);
}
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_follower(struct snd_kcontrol *master,
struct snd_kcontrol *follower,
unsigned int flags);
/* optional flags for follower */
#define SND_CTL_FOLLOWER_NEED_UPDATE (1 << 0)
/**
* snd_ctl_add_follower - Add a virtual follower control
* @master: vmaster element
* @follower: follower element to add
*
* Add a virtual follower control to the given master element created via
* snd_ctl_create_virtual_master() beforehand.
*
* All followers must be the same type (returning the same information
* via info callback). The function doesn't check it, so it's your
* responsibility.
*
* Also, some additional limitations:
* at most two channels,
* logarithmic volume control (dB level) thus no linear volume,
* master can only attenuate the volume without gain
*
* Return: Zero if successful or a negative error code.
*/
static inline int
snd_ctl_add_follower(struct snd_kcontrol *master, struct snd_kcontrol *follower)
{
return _snd_ctl_add_follower(master, follower, 0);
}
int snd_ctl_add_followers(struct snd_card *card, struct snd_kcontrol *master,
const char * const *list);
/**
* snd_ctl_add_follower_uncached - Add a virtual follower control
* @master: vmaster element
* @follower: follower element to add
*
* Add a virtual follower control to the given master.
* Unlike snd_ctl_add_follower(), the element added via this function
* is supposed to have volatile values, and get callback is called
* at each time queried from the master.
*
* When the control peeks the hardware values directly and the value
* can be changed by other means than the put callback of the element,
* this function should be used to keep the value always up-to-date.
*
* Return: Zero if successful or a negative error code.
*/
static inline int
snd_ctl_add_follower_uncached(struct snd_kcontrol *master,
struct snd_kcontrol *follower)
{
return _snd_ctl_add_follower(master, follower, SND_CTL_FOLLOWER_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(struct snd_kcontrol *kctl, bool hook_only);
#define snd_ctl_sync_vmaster_hook(kctl) snd_ctl_sync_vmaster(kctl, true)
int snd_ctl_apply_vmaster_followers(struct snd_kcontrol *kctl,
int (*func)(struct snd_kcontrol *vfollower,
struct snd_kcontrol *follower,
void *arg),
void *arg);
/*
* Control LED trigger layer
*/
#define SND_CTL_LAYER_MODULE_LED "snd-ctl-led"
#if IS_MODULE(CONFIG_SND_CTL_LED)
static inline int snd_ctl_led_request(void) { return snd_ctl_request_layer(SND_CTL_LAYER_MODULE_LED); }
#else
static inline int snd_ctl_led_request(void) { return 0; }
#endif
/*
* Helper functions for jack-detection controls
*/
struct snd_kcontrol *
snd_kctl_jack_new(const char *name, struct snd_card *card);
void snd_kctl_jack_report(struct snd_card *card,
struct snd_kcontrol *kctl, bool status);
#endif /* __SOUND_CONTROL_H */