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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /sound/core/vmaster.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'sound/core/vmaster.c')
-rw-r--r--sound/core/vmaster.c522
1 files changed, 522 insertions, 0 deletions
diff --git a/sound/core/vmaster.c b/sound/core/vmaster.c
new file mode 100644
index 000000000..d0f11f378
--- /dev/null
+++ b/sound/core/vmaster.c
@@ -0,0 +1,522 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Virtual master and follower controls
+ *
+ * Copyright (c) 2008 by Takashi Iwai <tiwai@suse.de>
+ */
+
+#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 follower 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 followers.
+ */
+struct link_master {
+ struct list_head followers;
+ 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 follower - this contains a follower control element
+ *
+ * It fakes the control callbacks with additional attenuation by the
+ * master control. A follower may have either one or two channels.
+ */
+
+struct link_follower {
+ 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 follower; /* the copy of original control entry */
+};
+
+static int follower_update(struct link_follower *follower)
+{
+ struct snd_ctl_elem_value *uctl;
+ int err, ch;
+
+ uctl = kzalloc(sizeof(*uctl), GFP_KERNEL);
+ if (!uctl)
+ return -ENOMEM;
+ uctl->id = follower->follower.id;
+ err = follower->follower.get(&follower->follower, uctl);
+ if (err < 0)
+ goto error;
+ for (ch = 0; ch < follower->info.count; ch++)
+ follower->vals[ch] = uctl->value.integer.value[ch];
+ error:
+ kfree(uctl);
+ return err < 0 ? err : 0;
+}
+
+/* get the follower ctl info and save the initial values */
+static int follower_init(struct link_follower *follower)
+{
+ struct snd_ctl_elem_info *uinfo;
+ int err;
+
+ if (follower->info.count) {
+ /* already initialized */
+ if (follower->flags & SND_CTL_FOLLOWER_NEED_UPDATE)
+ return follower_update(follower);
+ return 0;
+ }
+
+ uinfo = kmalloc(sizeof(*uinfo), GFP_KERNEL);
+ if (!uinfo)
+ return -ENOMEM;
+ uinfo->id = follower->follower.id;
+ err = follower->follower.info(&follower->follower, uinfo);
+ if (err < 0) {
+ kfree(uinfo);
+ return err;
+ }
+ follower->info.type = uinfo->type;
+ follower->info.count = uinfo->count;
+ if (follower->info.count > 2 ||
+ (follower->info.type != SNDRV_CTL_ELEM_TYPE_INTEGER &&
+ follower->info.type != SNDRV_CTL_ELEM_TYPE_BOOLEAN)) {
+ pr_err("ALSA: vmaster: invalid follower element\n");
+ kfree(uinfo);
+ return -EINVAL;
+ }
+ follower->info.min_val = uinfo->value.integer.min;
+ follower->info.max_val = uinfo->value.integer.max;
+ kfree(uinfo);
+
+ return follower_update(follower);
+}
+
+/* initialize master volume */
+static int master_init(struct link_master *master)
+{
+ struct link_follower *follower;
+
+ if (master->info.count)
+ return 0; /* already initialized */
+
+ list_for_each_entry(follower, &master->followers, list) {
+ int err = follower_init(follower);
+ if (err < 0)
+ return err;
+ master->info = follower->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 follower_get_val(struct link_follower *follower,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ int err, ch;
+
+ err = follower_init(follower);
+ if (err < 0)
+ return err;
+ for (ch = 0; ch < follower->info.count; ch++)
+ ucontrol->value.integer.value[ch] = follower->vals[ch];
+ return 0;
+}
+
+static int follower_put_val(struct link_follower *follower,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ int err, ch, vol;
+
+ err = master_init(follower->master);
+ if (err < 0)
+ return err;
+
+ switch (follower->info.type) {
+ case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
+ for (ch = 0; ch < follower->info.count; ch++)
+ ucontrol->value.integer.value[ch] &=
+ !!follower->master->val;
+ break;
+ case SNDRV_CTL_ELEM_TYPE_INTEGER:
+ for (ch = 0; ch < follower->info.count; ch++) {
+ /* max master volume is supposed to be 0 dB */
+ vol = ucontrol->value.integer.value[ch];
+ vol += follower->master->val - follower->master->info.max_val;
+ if (vol < follower->info.min_val)
+ vol = follower->info.min_val;
+ else if (vol > follower->info.max_val)
+ vol = follower->info.max_val;
+ ucontrol->value.integer.value[ch] = vol;
+ }
+ break;
+ }
+ return follower->follower.put(&follower->follower, ucontrol);
+}
+
+/*
+ * ctl callbacks for followers
+ */
+static int follower_info(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_info *uinfo)
+{
+ struct link_follower *follower = snd_kcontrol_chip(kcontrol);
+ return follower->follower.info(&follower->follower, uinfo);
+}
+
+static int follower_get(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct link_follower *follower = snd_kcontrol_chip(kcontrol);
+ return follower_get_val(follower, ucontrol);
+}
+
+static int follower_put(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct link_follower *follower = snd_kcontrol_chip(kcontrol);
+ int err, ch, changed = 0;
+
+ err = follower_init(follower);
+ if (err < 0)
+ return err;
+ for (ch = 0; ch < follower->info.count; ch++) {
+ if (follower->vals[ch] != ucontrol->value.integer.value[ch]) {
+ changed = 1;
+ follower->vals[ch] = ucontrol->value.integer.value[ch];
+ }
+ }
+ if (!changed)
+ return 0;
+ err = follower_put_val(follower, ucontrol);
+ if (err < 0)
+ return err;
+ return 1;
+}
+
+static int follower_tlv_cmd(struct snd_kcontrol *kcontrol,
+ int op_flag, unsigned int size,
+ unsigned int __user *tlv)
+{
+ struct link_follower *follower = snd_kcontrol_chip(kcontrol);
+ /* FIXME: this assumes that the max volume is 0 dB */
+ return follower->follower.tlv.c(&follower->follower, op_flag, size, tlv);
+}
+
+static void follower_free(struct snd_kcontrol *kcontrol)
+{
+ struct link_follower *follower = snd_kcontrol_chip(kcontrol);
+ if (follower->follower.private_free)
+ follower->follower.private_free(&follower->follower);
+ if (follower->master)
+ list_del(&follower->list);
+ kfree(follower);
+}
+
+/*
+ * Add a follower control to the group with the given master control
+ *
+ * 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), no linear volume
+ * - master can only attenuate the volume, no gain
+ */
+int _snd_ctl_add_follower(struct snd_kcontrol *master,
+ struct snd_kcontrol *follower,
+ unsigned int flags)
+{
+ struct link_master *master_link = snd_kcontrol_chip(master);
+ struct link_follower *srec;
+
+ srec = kzalloc(struct_size(srec, follower.vd, follower->count),
+ GFP_KERNEL);
+ if (!srec)
+ return -ENOMEM;
+ srec->kctl = follower;
+ srec->follower = *follower;
+ memcpy(srec->follower.vd, follower->vd, follower->count * sizeof(*follower->vd));
+ srec->master = master_link;
+ srec->flags = flags;
+
+ /* override callbacks */
+ follower->info = follower_info;
+ follower->get = follower_get;
+ follower->put = follower_put;
+ if (follower->vd[0].access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK)
+ follower->tlv.c = follower_tlv_cmd;
+ follower->private_data = srec;
+ follower->private_free = follower_free;
+
+ list_add_tail(&srec->list, &master_link->followers);
+ return 0;
+}
+EXPORT_SYMBOL(_snd_ctl_add_follower);
+
+/*
+ * 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_followers(struct link_master *master, int old_val, int new_val)
+{
+ struct link_follower *follower;
+ struct snd_ctl_elem_value *uval;
+
+ uval = kmalloc(sizeof(*uval), GFP_KERNEL);
+ if (!uval)
+ return -ENOMEM;
+ list_for_each_entry(follower, &master->followers, list) {
+ master->val = old_val;
+ uval->id = follower->follower.id;
+ follower_get_val(follower, uval);
+ master->val = new_val;
+ follower_put_val(follower, 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_followers(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_follower *follower, *n;
+
+ /* free all follower links and retore the original follower kctls */
+ list_for_each_entry_safe(follower, n, &master->followers, list) {
+ struct snd_kcontrol *sctl = follower->kctl;
+ struct list_head olist = sctl->list;
+ memcpy(sctl, &follower->follower, sizeof(*sctl));
+ memcpy(sctl->vd, follower->follower.vd,
+ sctl->count * sizeof(*sctl->vd));
+ sctl->list = olist; /* keep the current linked-list */
+ kfree(follower);
+ }
+ 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 follower controls
+ * via snd_ctl_add_follower() or snd_ctl_add_follower_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->followers);
+
+ 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) {
+ unsigned int type = tlv[SNDRV_CTL_TLVO_TYPE];
+ if (type == SNDRV_CTL_TLVT_DB_SCALE ||
+ type == SNDRV_CTL_TLVT_DB_MINMAX ||
+ type == 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 followers and hook
+ * @kcontrol: vmaster kctl element
+ * @hook_only: sync only the hook
+ *
+ * Forcibly call the put callback of each follower 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_followers(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);
+
+/**
+ * snd_ctl_apply_vmaster_followers - Apply function to each vmaster follower
+ * @kctl: vmaster kctl element
+ * @func: function to apply
+ * @arg: optional function argument
+ *
+ * Apply the function @func to each follower kctl of the given vmaster kctl.
+ *
+ * Return: 0 if successful, or a negative error code
+ */
+int snd_ctl_apply_vmaster_followers(struct snd_kcontrol *kctl,
+ int (*func)(struct snd_kcontrol *vfollower,
+ struct snd_kcontrol *follower,
+ void *arg),
+ void *arg)
+{
+ struct link_master *master;
+ struct link_follower *follower;
+ int err;
+
+ master = snd_kcontrol_chip(kctl);
+ err = master_init(master);
+ if (err < 0)
+ return err;
+ list_for_each_entry(follower, &master->followers, list) {
+ err = func(follower->kctl, &follower->follower, arg);
+ if (err < 0)
+ return err;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(snd_ctl_apply_vmaster_followers);