271 lines
10 KiB
C
271 lines
10 KiB
C
/***************************************************************************
|
|
* __________ __ ___.
|
|
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
|
|
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
|
|
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
|
|
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
|
|
* \/ \/ \/ \/ \/
|
|
*
|
|
* Copyright (C) 2016 Amaury Pouly
|
|
*
|
|
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
|
|
* KIND, either express or implied.
|
|
*
|
|
****************************************************************************/
|
|
#include "alsa-controls.h"
|
|
#include "panic.h"
|
|
#include "debug.h"
|
|
#include <stdlib.h>
|
|
|
|
/* alsa control handle, we keep it open at all times */
|
|
static snd_ctl_t *alsa_ctl;
|
|
/* list of all controls, we allocate and fill it once, so we can easily lookup */
|
|
static snd_ctl_elem_list_t *alsa_ctl_list;
|
|
static unsigned alsa_ctl_count;
|
|
/* for each control, we store some info to avoid constantly using ALSA's horrible lookup functions */
|
|
static struct ctl_t
|
|
{
|
|
snd_ctl_elem_id_t *id; /* ID associated with the control */
|
|
const char *name; /* name of the control */
|
|
snd_ctl_elem_type_t type; /* control type (boolean, enum, ...) */
|
|
unsigned count; /* dimension of the control */
|
|
unsigned items; /* number of items (for enums) */
|
|
const char **enum_name; /* names of the enum, indexed by ALSA index */
|
|
} *alsa_ctl_info;
|
|
|
|
#if defined(DEBUG)
|
|
static const char *alsa_ctl_type_name(snd_ctl_elem_type_t type)
|
|
{
|
|
switch(type)
|
|
{
|
|
case SND_CTL_ELEM_TYPE_BOOLEAN: return "BOOLEAN";
|
|
case SND_CTL_ELEM_TYPE_INTEGER: return "INTEGER";
|
|
case SND_CTL_ELEM_TYPE_ENUMERATED: return "ENUMERATED";
|
|
default: return "???";
|
|
}
|
|
}
|
|
#endif
|
|
|
|
void alsa_controls_init(const char *name)
|
|
{
|
|
/* allocate list on heap because it is used it is used in other functions */
|
|
snd_ctl_elem_list_malloc(&alsa_ctl_list);
|
|
/* there is only one card and "default" always works */
|
|
if(snd_ctl_open(&alsa_ctl, name, 0) < 0)
|
|
panicf("Cannot open ctl\n");
|
|
/* ALSA is braindead: first "get" the list -> only retrieve count */
|
|
if(snd_ctl_elem_list(alsa_ctl, alsa_ctl_list) < 0)
|
|
panicf("Cannot get element list\n");
|
|
/* now we can allocate the list since the know the size */
|
|
alsa_ctl_count = snd_ctl_elem_list_get_count(alsa_ctl_list);
|
|
if(snd_ctl_elem_list_alloc_space(alsa_ctl_list, alsa_ctl_count) < 0)
|
|
panicf("Cannot allocate space for element list\n");
|
|
/* ... and get the list again! */
|
|
if(snd_ctl_elem_list(alsa_ctl, alsa_ctl_list) < 0)
|
|
panicf("Cannot get element list\n");
|
|
/* now cache the info */
|
|
alsa_ctl_info = malloc(sizeof(struct ctl_t) * alsa_ctl_count);
|
|
snd_ctl_elem_info_t *info;
|
|
snd_ctl_elem_info_malloc(&info);
|
|
for(unsigned i = 0; i < alsa_ctl_count; i++)
|
|
{
|
|
/* allocate the ID and retrieve it */
|
|
snd_ctl_elem_id_malloc(&alsa_ctl_info[i].id);
|
|
snd_ctl_elem_list_get_id(alsa_ctl_list, i, alsa_ctl_info[i].id);
|
|
/* NOTE: name is valid as long as the ID lives; since we keep both, no need to copy */
|
|
alsa_ctl_info[i].name = snd_ctl_elem_id_get_name(alsa_ctl_info[i].id);
|
|
/* get info */
|
|
snd_ctl_elem_info_set_id(info, alsa_ctl_info[i].id);
|
|
if(snd_ctl_elem_info(alsa_ctl, info) < 0)
|
|
panicf("Cannot get control '%s' info", alsa_ctl_info[i].name);
|
|
alsa_ctl_info[i].type = snd_ctl_elem_info_get_type(info);
|
|
alsa_ctl_info[i].count = snd_ctl_elem_info_get_count(info);
|
|
if(alsa_ctl_info[i].type == SND_CTL_ELEM_TYPE_ENUMERATED)
|
|
{
|
|
alsa_ctl_info[i].items = snd_ctl_elem_info_get_items(info);
|
|
alsa_ctl_info[i].enum_name = malloc(sizeof(char *) * alsa_ctl_info[i].items);
|
|
for(unsigned j = 0; j < alsa_ctl_info[i].items; j++)
|
|
{
|
|
snd_ctl_elem_info_set_item(info, j);
|
|
if(snd_ctl_elem_info(alsa_ctl, info) < 0)
|
|
panicf("Cannot get control '%s' info for item %u", alsa_ctl_info[i].name, j);
|
|
/* NOTE: copy string because it becomes invalid after info is freed */
|
|
alsa_ctl_info[i].enum_name[j] = strdup(snd_ctl_elem_info_get_item_name(info));
|
|
}
|
|
}
|
|
else
|
|
alsa_ctl_info[i].items = 0;
|
|
}
|
|
snd_ctl_elem_info_free(info);
|
|
|
|
DEBUGF("ALSA controls:\n");
|
|
for(unsigned i = 0; i < alsa_ctl_count; i++)
|
|
{
|
|
DEBUGF("- name='%s', type=%s, count=%u\n", alsa_ctl_info[i].name,
|
|
alsa_ctl_type_name(alsa_ctl_info[i].type), alsa_ctl_info[i].count);
|
|
if(alsa_ctl_info[i].type == SND_CTL_ELEM_TYPE_ENUMERATED)
|
|
{
|
|
DEBUGF(" items:");
|
|
for(unsigned j = 0; j < alsa_ctl_info[i].items; j++)
|
|
{
|
|
if(j != 0)
|
|
DEBUGF(",");
|
|
DEBUGF(" '%s'", alsa_ctl_info[i].enum_name[j]);
|
|
}
|
|
DEBUGF("\n");
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
void alsa_controls_close(void)
|
|
{
|
|
snd_ctl_close(alsa_ctl);
|
|
}
|
|
|
|
/* find a control element ID by name, return -1 of not found or index into array */
|
|
int alsa_controls_find(const char *name)
|
|
{
|
|
/* enumerate controls */
|
|
for(unsigned i = 0; i < alsa_ctl_count; i++)
|
|
if(strcmp(alsa_ctl_info[i].name, name) == 0)
|
|
return i;
|
|
/* not found */
|
|
return -1;
|
|
}
|
|
|
|
bool alsa_has_control(const char *name)
|
|
{
|
|
return alsa_controls_find(name) >= 0;
|
|
}
|
|
|
|
/* find a control element enum index by name, return -1 if not found */
|
|
int alsa_controls_find_enum(const char *name, const char *enum_name)
|
|
{
|
|
/* find control */
|
|
int idx = alsa_controls_find(name);
|
|
if(idx < 0)
|
|
panicf("Cannot find control '%s'", name);
|
|
/* list items */
|
|
for(unsigned i = 0; i < alsa_ctl_info[idx].items; i++)
|
|
{
|
|
if(strcmp(alsa_ctl_info[idx].enum_name[i], enum_name) == 0)
|
|
return i;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
/* set/get a control, potentially supports several values */
|
|
void alsa_controls_get_set(bool get, const char *name, snd_ctl_elem_type_t type,
|
|
unsigned nr_values, long *val)
|
|
{
|
|
snd_ctl_elem_value_t *value;
|
|
/* allocate things on stack to speedup */
|
|
snd_ctl_elem_value_alloca(&value);
|
|
/* find control */
|
|
int idx = alsa_controls_find(name);
|
|
if(idx < 0)
|
|
panicf("Cannot find control '%s'", name);
|
|
/* check the type of the control */
|
|
if(alsa_ctl_info[idx].type != type)
|
|
panicf("Control '%s' has wrong type (got %d, expected %d", name,
|
|
alsa_ctl_info[idx].type, type);
|
|
if(alsa_ctl_info[idx].count != nr_values)
|
|
panicf("Control '%s' has wrong count (got %u, expected %u)",
|
|
name, alsa_ctl_info[idx].count, nr_values);
|
|
snd_ctl_elem_value_set_id(value, alsa_ctl_info[idx].id);
|
|
/* set value */
|
|
if(get)
|
|
{
|
|
/* read value */
|
|
if(snd_ctl_elem_read(alsa_ctl, value) < 0)
|
|
panicf("Cannot read control '%s'", name);
|
|
for(unsigned i = 0; i < nr_values; i++)
|
|
{
|
|
/* ALSA is braindead: there are "typed" setters but they all take long anyway */
|
|
if(type == SND_CTL_ELEM_TYPE_BOOLEAN)
|
|
val[i] = snd_ctl_elem_value_get_boolean(value, i);
|
|
else if(type == SND_CTL_ELEM_TYPE_INTEGER)
|
|
val[i] = snd_ctl_elem_value_get_integer(value, i);
|
|
else if(type == SND_CTL_ELEM_TYPE_ENUMERATED)
|
|
val[i] = snd_ctl_elem_value_get_enumerated(value, i);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
for(unsigned i = 0; i < nr_values; i++)
|
|
{
|
|
/* ALSA is braindead: there are "typed" setters but they all take long anyway */
|
|
if(type == SND_CTL_ELEM_TYPE_BOOLEAN)
|
|
snd_ctl_elem_value_set_boolean(value, i, val[i]);
|
|
else if(type == SND_CTL_ELEM_TYPE_INTEGER)
|
|
snd_ctl_elem_value_set_integer(value, i, val[i]);
|
|
else if(type == SND_CTL_ELEM_TYPE_ENUMERATED)
|
|
snd_ctl_elem_value_set_enumerated(value, i, val[i]);
|
|
}
|
|
/* write value */
|
|
if(snd_ctl_elem_write(alsa_ctl, value) < 0)
|
|
panicf("Cannot write control '%s'", name);
|
|
}
|
|
}
|
|
|
|
/* set a control, potentially supports several values */
|
|
void alsa_controls_set(const char *name, snd_ctl_elem_type_t type,
|
|
unsigned nr_values, long *val)
|
|
{
|
|
return alsa_controls_get_set(false, name, type, nr_values, val);
|
|
}
|
|
|
|
/* get a control, potentially supports several values */
|
|
void alsa_controls_get(const char *name, snd_ctl_elem_type_t type,
|
|
unsigned nr_values, long *val)
|
|
{
|
|
return alsa_controls_get_set(true, name, type, nr_values, val);
|
|
}
|
|
|
|
/* get control information */
|
|
void alsa_controls_get_info(const char *name, int *out_count)
|
|
{
|
|
/* find control */
|
|
int idx = alsa_controls_find(name);
|
|
if(idx < 0)
|
|
panicf("Cannot find control '%s'", name);
|
|
/* get info */
|
|
*out_count = alsa_ctl_info[idx].count;
|
|
}
|
|
|
|
/* helper function: set a control with a single boolean value */
|
|
void alsa_controls_set_bool(const char *name, bool val)
|
|
{
|
|
long lval = val;
|
|
alsa_controls_set(name, SND_CTL_ELEM_TYPE_BOOLEAN, 1, &lval);
|
|
}
|
|
|
|
/* helper function: set a control with a single enum value */
|
|
void alsa_controls_set_enum(const char *name, const char *enum_name)
|
|
{
|
|
long idx = alsa_controls_find_enum(name, enum_name);
|
|
if(idx < 0)
|
|
panicf("Cannot find enum '%s' for control '%s'", enum_name, name);
|
|
alsa_controls_set(name, SND_CTL_ELEM_TYPE_ENUMERATED, 1, &idx);
|
|
}
|
|
|
|
/* helper function: set a control with one or more integers */
|
|
void alsa_controls_set_ints(const char *name, int count, long *val)
|
|
{
|
|
return alsa_controls_set(name, SND_CTL_ELEM_TYPE_INTEGER, count, val);
|
|
}
|
|
|
|
/* helper function: get a control with a single boolean value */
|
|
bool alsa_controls_get_bool(const char *name)
|
|
{
|
|
long lval = 0;
|
|
alsa_controls_get(name, SND_CTL_ELEM_TYPE_BOOLEAN, 1, &lval);
|
|
return lval != 0;
|
|
}
|