linux/include/sound/control.h
Jaroslav Kysela 22d8de62f1 ALSA: control - add generic LED trigger module as the new control layer
The recent laptops have usually two LEDs assigned to reflect
the speaker and microphone mute state. This implementation
adds a tiny layer on top of the control API which calculates
the state for those LEDs using the driver callbacks.

Two new access flags are introduced to describe the controls
which affects the audio path settings (an easy code change
for drivers).

The LED resource can be shared with multiple sound cards with
this code. The user space controls may be added to the state
chain on demand, too.

This code should replace the LED code in the HDA driver and
add a possibility to easy extend the other drivers (ASoC
codecs etc.).

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20210317172945.842280-4-perex@perex.cz
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-03-30 15:33:58 +02:00

294 lines
9.7 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_VALIDATION
#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 fasync_struct *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);
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
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);
}
/**
* 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 */