linux/sound/core/vmaster.c
Takashi Iwai 1ba65ae4bd ALSA: vmaster: Fix the regression of missing vmaster hook call
The commit [1ca2f2ec: ALSA: vmaster: Add snd_ctl_sync_vmaster() helper
function] changed master_put() function and the check for the required
vmaster hook call is wrongly performed now, which results in the
missing hook call upon "Master Playback Switch" value changes.
This patch corrects the check logic.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-07-03 14:01:32 +02:00

487 lines
13 KiB
C

/*
* Virtual master and slave controls
*
* Copyright (c) 2008 by Takashi Iwai <tiwai@suse.de>
*
* 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, version 2.
*
*/
#include <linux/slab.h>
#include <linux/export.h>
#include <sound/core.h>
#include <sound/control.h>
#include <sound/tlv.h>
/*
* a subset of information returned via ctl info callback
*/
struct link_ctl_info {
snd_ctl_elem_type_t type; /* value type */
int count; /* item count */
int min_val, max_val; /* min, max values */
};
/*
* link master - this contains a list of slave controls that are
* identical types, i.e. info returns the same value type and value
* ranges, but may have different number of counts.
*
* The master control is so far only mono volume/switch for simplicity.
* The same value will be applied to all slaves.
*/
struct link_master {
struct list_head slaves;
struct link_ctl_info info;
int val; /* the master value */
unsigned int tlv[4];
void (*hook)(void *private_data, int);
void *hook_private_data;
};
/*
* link slave - this contains a slave control element
*
* It fakes the control callbacsk with additional attenuation by the
* master control. A slave may have either one or two channels.
*/
struct link_slave {
struct list_head list;
struct link_master *master;
struct link_ctl_info info;
int vals[2]; /* current values */
unsigned int flags;
struct snd_kcontrol *kctl; /* original kcontrol pointer */
struct snd_kcontrol slave; /* the copy of original control entry */
};
static int slave_update(struct link_slave *slave)
{
struct snd_ctl_elem_value *uctl;
int err, ch;
uctl = kmalloc(sizeof(*uctl), GFP_KERNEL);
if (!uctl)
return -ENOMEM;
uctl->id = slave->slave.id;
err = slave->slave.get(&slave->slave, uctl);
for (ch = 0; ch < slave->info.count; ch++)
slave->vals[ch] = uctl->value.integer.value[ch];
kfree(uctl);
return 0;
}
/* get the slave ctl info and save the initial values */
static int slave_init(struct link_slave *slave)
{
struct snd_ctl_elem_info *uinfo;
int err;
if (slave->info.count) {
/* already initialized */
if (slave->flags & SND_CTL_SLAVE_NEED_UPDATE)
return slave_update(slave);
return 0;
}
uinfo = kmalloc(sizeof(*uinfo), GFP_KERNEL);
if (!uinfo)
return -ENOMEM;
uinfo->id = slave->slave.id;
err = slave->slave.info(&slave->slave, uinfo);
if (err < 0) {
kfree(uinfo);
return err;
}
slave->info.type = uinfo->type;
slave->info.count = uinfo->count;
if (slave->info.count > 2 ||
(slave->info.type != SNDRV_CTL_ELEM_TYPE_INTEGER &&
slave->info.type != SNDRV_CTL_ELEM_TYPE_BOOLEAN)) {
snd_printk(KERN_ERR "invalid slave element\n");
kfree(uinfo);
return -EINVAL;
}
slave->info.min_val = uinfo->value.integer.min;
slave->info.max_val = uinfo->value.integer.max;
kfree(uinfo);
return slave_update(slave);
}
/* initialize master volume */
static int master_init(struct link_master *master)
{
struct link_slave *slave;
if (master->info.count)
return 0; /* already initialized */
list_for_each_entry(slave, &master->slaves, list) {
int err = slave_init(slave);
if (err < 0)
return err;
master->info = slave->info;
master->info.count = 1; /* always mono */
/* set full volume as default (= no attenuation) */
master->val = master->info.max_val;
if (master->hook)
master->hook(master->hook_private_data, master->val);
return 1;
}
return -ENOENT;
}
static int slave_get_val(struct link_slave *slave,
struct snd_ctl_elem_value *ucontrol)
{
int err, ch;
err = slave_init(slave);
if (err < 0)
return err;
for (ch = 0; ch < slave->info.count; ch++)
ucontrol->value.integer.value[ch] = slave->vals[ch];
return 0;
}
static int slave_put_val(struct link_slave *slave,
struct snd_ctl_elem_value *ucontrol)
{
int err, ch, vol;
err = master_init(slave->master);
if (err < 0)
return err;
switch (slave->info.type) {
case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
for (ch = 0; ch < slave->info.count; ch++)
ucontrol->value.integer.value[ch] &=
!!slave->master->val;
break;
case SNDRV_CTL_ELEM_TYPE_INTEGER:
for (ch = 0; ch < slave->info.count; ch++) {
/* max master volume is supposed to be 0 dB */
vol = ucontrol->value.integer.value[ch];
vol += slave->master->val - slave->master->info.max_val;
if (vol < slave->info.min_val)
vol = slave->info.min_val;
else if (vol > slave->info.max_val)
vol = slave->info.max_val;
ucontrol->value.integer.value[ch] = vol;
}
break;
}
return slave->slave.put(&slave->slave, ucontrol);
}
/*
* ctl callbacks for slaves
*/
static int slave_info(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_info *uinfo)
{
struct link_slave *slave = snd_kcontrol_chip(kcontrol);
return slave->slave.info(&slave->slave, uinfo);
}
static int slave_get(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *ucontrol)
{
struct link_slave *slave = snd_kcontrol_chip(kcontrol);
return slave_get_val(slave, ucontrol);
}
static int slave_put(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *ucontrol)
{
struct link_slave *slave = snd_kcontrol_chip(kcontrol);
int err, ch, changed = 0;
err = slave_init(slave);
if (err < 0)
return err;
for (ch = 0; ch < slave->info.count; ch++) {
if (slave->vals[ch] != ucontrol->value.integer.value[ch]) {
changed = 1;
slave->vals[ch] = ucontrol->value.integer.value[ch];
}
}
if (!changed)
return 0;
err = slave_put_val(slave, ucontrol);
if (err < 0)
return err;
return 1;
}
static int slave_tlv_cmd(struct snd_kcontrol *kcontrol,
int op_flag, unsigned int size,
unsigned int __user *tlv)
{
struct link_slave *slave = snd_kcontrol_chip(kcontrol);
/* FIXME: this assumes that the max volume is 0 dB */
return slave->slave.tlv.c(&slave->slave, op_flag, size, tlv);
}
static void slave_free(struct snd_kcontrol *kcontrol)
{
struct link_slave *slave = snd_kcontrol_chip(kcontrol);
if (slave->slave.private_free)
slave->slave.private_free(&slave->slave);
if (slave->master)
list_del(&slave->list);
kfree(slave);
}
/*
* Add a slave control to the group with the given master control
*
* All slaves 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), no linear volume
* - master can only attenuate the volume, no gain
*/
int _snd_ctl_add_slave(struct snd_kcontrol *master, struct snd_kcontrol *slave,
unsigned int flags)
{
struct link_master *master_link = snd_kcontrol_chip(master);
struct link_slave *srec;
srec = kzalloc(sizeof(*srec) +
slave->count * sizeof(*slave->vd), GFP_KERNEL);
if (!srec)
return -ENOMEM;
srec->kctl = slave;
srec->slave = *slave;
memcpy(srec->slave.vd, slave->vd, slave->count * sizeof(*slave->vd));
srec->master = master_link;
srec->flags = flags;
/* override callbacks */
slave->info = slave_info;
slave->get = slave_get;
slave->put = slave_put;
if (slave->vd[0].access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK)
slave->tlv.c = slave_tlv_cmd;
slave->private_data = srec;
slave->private_free = slave_free;
list_add_tail(&srec->list, &master_link->slaves);
return 0;
}
EXPORT_SYMBOL(_snd_ctl_add_slave);
/*
* ctl callbacks for master controls
*/
static int master_info(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_info *uinfo)
{
struct link_master *master = snd_kcontrol_chip(kcontrol);
int ret;
ret = master_init(master);
if (ret < 0)
return ret;
uinfo->type = master->info.type;
uinfo->count = master->info.count;
uinfo->value.integer.min = master->info.min_val;
uinfo->value.integer.max = master->info.max_val;
return 0;
}
static int master_get(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *ucontrol)
{
struct link_master *master = snd_kcontrol_chip(kcontrol);
int err = master_init(master);
if (err < 0)
return err;
ucontrol->value.integer.value[0] = master->val;
return 0;
}
static int sync_slaves(struct link_master *master, int old_val, int new_val)
{
struct link_slave *slave;
struct snd_ctl_elem_value *uval;
uval = kmalloc(sizeof(*uval), GFP_KERNEL);
if (!uval)
return -ENOMEM;
list_for_each_entry(slave, &master->slaves, list) {
master->val = old_val;
uval->id = slave->slave.id;
slave_get_val(slave, uval);
master->val = new_val;
slave_put_val(slave, uval);
}
kfree(uval);
return 0;
}
static int master_put(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *ucontrol)
{
struct link_master *master = snd_kcontrol_chip(kcontrol);
int err, new_val, old_val;
bool first_init;
err = master_init(master);
if (err < 0)
return err;
first_init = err;
old_val = master->val;
new_val = ucontrol->value.integer.value[0];
if (new_val == old_val)
return 0;
err = sync_slaves(master, old_val, new_val);
if (err < 0)
return err;
if (master->hook && !first_init)
master->hook(master->hook_private_data, master->val);
return 1;
}
static void master_free(struct snd_kcontrol *kcontrol)
{
struct link_master *master = snd_kcontrol_chip(kcontrol);
struct link_slave *slave, *n;
/* free all slave links and retore the original slave kctls */
list_for_each_entry_safe(slave, n, &master->slaves, list) {
struct snd_kcontrol *sctl = slave->kctl;
struct list_head olist = sctl->list;
memcpy(sctl, &slave->slave, sizeof(*sctl));
memcpy(sctl->vd, slave->slave.vd,
sctl->count * sizeof(*sctl->vd));
sctl->list = olist; /* keep the current linked-list */
kfree(slave);
}
kfree(master);
}
/**
* snd_ctl_make_virtual_master - Create a virtual master control
* @name: name string of the control element to create
* @tlv: optional TLV int array for dB information
*
* Creates a virtual master control with the given name string.
*
* After creating a vmaster element, you can add the slave controls
* via snd_ctl_add_slave() or snd_ctl_add_slave_uncached().
*
* The optional argument @tlv can be used to specify the TLV information
* for dB scale of the master control. It should be a single element
* with #SNDRV_CTL_TLVT_DB_SCALE, #SNDRV_CTL_TLV_DB_MINMAX or
* #SNDRV_CTL_TLVT_DB_MINMAX_MUTE type, and should be the max 0dB.
*
* Return: The created control element, or %NULL for errors (ENOMEM).
*/
struct snd_kcontrol *snd_ctl_make_virtual_master(char *name,
const unsigned int *tlv)
{
struct link_master *master;
struct snd_kcontrol *kctl;
struct snd_kcontrol_new knew;
memset(&knew, 0, sizeof(knew));
knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
knew.name = name;
knew.info = master_info;
master = kzalloc(sizeof(*master), GFP_KERNEL);
if (!master)
return NULL;
INIT_LIST_HEAD(&master->slaves);
kctl = snd_ctl_new1(&knew, master);
if (!kctl) {
kfree(master);
return NULL;
}
/* override some callbacks */
kctl->info = master_info;
kctl->get = master_get;
kctl->put = master_put;
kctl->private_free = master_free;
/* additional (constant) TLV read */
if (tlv &&
(tlv[0] == SNDRV_CTL_TLVT_DB_SCALE ||
tlv[0] == SNDRV_CTL_TLVT_DB_MINMAX ||
tlv[0] == SNDRV_CTL_TLVT_DB_MINMAX_MUTE)) {
kctl->vd[0].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ;
memcpy(master->tlv, tlv, sizeof(master->tlv));
kctl->tlv.p = master->tlv;
}
return kctl;
}
EXPORT_SYMBOL(snd_ctl_make_virtual_master);
/**
* snd_ctl_add_vmaster_hook - Add a hook to a vmaster control
* @kcontrol: vmaster kctl element
* @hook: the hook function
* @private_data: the private_data pointer to be saved
*
* Adds the given hook to the vmaster control element so that it's called
* at each time when the value is changed.
*
* Return: Zero.
*/
int snd_ctl_add_vmaster_hook(struct snd_kcontrol *kcontrol,
void (*hook)(void *private_data, int),
void *private_data)
{
struct link_master *master = snd_kcontrol_chip(kcontrol);
master->hook = hook;
master->hook_private_data = private_data;
return 0;
}
EXPORT_SYMBOL_GPL(snd_ctl_add_vmaster_hook);
/**
* snd_ctl_sync_vmaster - Sync the vmaster slaves and hook
* @kcontrol: vmaster kctl element
* @hook_only: sync only the hook
*
* Forcibly call the put callback of each slave and call the hook function
* to synchronize with the current value of the given vmaster element.
* NOP when NULL is passed to @kcontrol.
*/
void snd_ctl_sync_vmaster(struct snd_kcontrol *kcontrol, bool hook_only)
{
struct link_master *master;
bool first_init = false;
if (!kcontrol)
return;
master = snd_kcontrol_chip(kcontrol);
if (!hook_only) {
int err = master_init(master);
if (err < 0)
return;
first_init = err;
err = sync_slaves(master, master->val, master->val);
if (err < 0)
return;
}
if (master->hook && !first_init)
master->hook(master->hook_private_data, master->val);
}
EXPORT_SYMBOL_GPL(snd_ctl_sync_vmaster);