sound/pci/hda/vmaster.c

   1 /*
   2  * Virtual master and slave controls
   3  *
   4  *  Copyright (c) 2008 by Takashi Iwai <tiwai@suse.de>
   5  *
   6  *  This program is free software; you can redistribute it and/or
   7  *  modify it under the terms of the GNU General Public License as
   8  *  published by the Free Software Foundation, version 2.
   9  *
  10  */
  11
  12 #include <linux/slab.h>
  13 #include <sound/core.h>
  14 #include <sound/control.h>
  15
  16 /*
  17  * a subset of information returned via ctl info callback
  18  */
  19 struct link_ctl_info {
  20         int type;               /* value type */
  21         int count;              /* item count */
  22         int min_val, max_val;   /* min, max values */
  23 };
  24
  25 /*
  26  * link master - this contains a list of slave controls that are
  27  * identical types, i.e. info returns the same value type and value
  28  * ranges, but may have different number of counts.
  29  *
  30  * The master control is so far only mono volume/switch for simplicity.
  31  * The same value will be applied to all slaves.
  32  */
  33 struct link_master {
  34         struct list_head slaves;
  35         struct link_ctl_info info;
  36         int val;                /* the master value */
  37 };
  38
  39 /*
  40  * link slave - this contains a slave control element
  41  *
  42  * It fakes the control callbacsk with additional attenuation by the
  43  * master control.  A slave may have either one or two channels.
  44  */
  45
  46 struct link_slave {
  47         struct list_head list;
  48         struct link_master *master;
  49         struct link_ctl_info info;
  50         int vals[2];            /* current values */
  51         struct snd_kcontrol slave; /* the copy of original control entry */
  52 };
  53
  54 /* get the slave ctl info and save the initial values */
  55 static int slave_init(struct link_slave *slave)
  56 {
  57         struct snd_ctl_elem_info *uinfo;
  58         struct snd_ctl_elem_value *uctl;
  59         int err, ch;
  60
  61         if (slave->info.count)
  62                 return 0; /* already initialized */
  63
  64         uinfo = kmalloc(sizeof(*uinfo), GFP_KERNEL);
  65         if (!uinfo)
  66                 return -ENOMEM;
  67         uinfo->id = slave->slave.id;
  68         err = slave->slave.info(&slave->slave, uinfo);
  69         if (err < 0) {
  70                 kfree(uinfo);
  71                 return err;
  72         }
  73         slave->info.type = uinfo->type;
  74         slave->info.count = uinfo->count;
  75         if (slave->info.count > 2  ||
  76             (slave->info.type != SNDRV_CTL_ELEM_TYPE_INTEGER &&
  77              slave->info.type != SNDRV_CTL_ELEM_TYPE_BOOLEAN)) {
  78                 snd_printk(KERN_ERR "invalid slave element\n");
  79                 kfree(uinfo);
  80                 return -EINVAL;
  81         }
  82         slave->info.min_val = uinfo->value.integer.min;
  83         slave->info.max_val = uinfo->value.integer.max;
  84         kfree(uinfo);
  85
  86         uctl = kmalloc(sizeof(*uctl), GFP_KERNEL);
  87         if (!uctl)
  88                 return -ENOMEM;
  89         uctl->id = slave->slave.id;
  90         err = slave->slave.get(&slave->slave, uctl);
  91         for (ch = 0; ch < slave->info.count; ch++)
  92                 slave->vals[ch] = uctl->value.integer.value[ch];
  93         kfree(uctl);
  94         return 0;
  95 }
  96
  97 /* initialize master volume */
  98 static int master_init(struct link_master *master)
  99 {
 100         struct link_slave *slave;
 101
 102         if (master->info.count)
 103                 return 0; /* already initialized */
 104
 105         list_for_each_entry(slave, &master->slaves, list) {
 106                 int err = slave_init(slave);
 107                 if (err < 0)
 108                         return err;
 109                 master->info = slave->info;
 110                 master->info.count = 1; /* always mono */
 111                 /* set full volume as default (= no attenuation) */
 112                 master->val = master->info.max_val;
 113                 return 0;
 114         }
 115         return -ENOENT;
 116 }
 117
 118 static int slave_get_val(struct link_slave *slave,
 119                          struct snd_ctl_elem_value *ucontrol)
 120 {
 121         int err, ch;
 122
 123         err = slave_init(slave);
 124         if (err < 0)
 125                 return err;
 126         for (ch = 0; ch < slave->info.count; ch++)
 127                 ucontrol->value.integer.value[ch] = slave->vals[ch];
 128         return 0;
 129 }
 130
 131 static int slave_put_val(struct link_slave *slave,
 132                          struct snd_ctl_elem_value *ucontrol)
 133 {
 134         int err, ch, vol;
 135
 136         err = master_init(slave->master);
 137         if (err < 0)
 138                 return err;
 139
 140         switch (slave->info.type) {
 141         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 142                 for (ch = 0; ch < slave->info.count; ch++)
 143                         ucontrol->value.integer.value[ch] &=
 144                                 !!slave->master->val;
 145                 break;
 146         case SNDRV_CTL_ELEM_TYPE_INTEGER:
 147                 for (ch = 0; ch < slave->info.count; ch++) {
 148                         /* max master volume is supposed to be 0 dB */
 149                         vol = ucontrol->value.integer.value[ch];
 150                         vol += slave->master->val - slave->master->info.max_val;
 151                         if (vol < slave->info.min_val)
 152                                 vol = slave->info.min_val;
 153                         else if (vol > slave->info.max_val)
 154                                 vol = slave->info.max_val;
 155                         ucontrol->value.integer.value[ch] = vol;
 156                 }
 157                 break;
 158         }
 159         return slave->slave.put(&slave->slave, ucontrol);
 160 }
 161
 162 /*
 163  * ctl callbacks for slaves
 164  */
 165 static int slave_info(struct snd_kcontrol *kcontrol,
 166                       struct snd_ctl_elem_info *uinfo)
 167 {
 168         struct link_slave *slave = snd_kcontrol_chip(kcontrol);
 169         return slave->slave.info(&slave->slave, uinfo);
 170 }
 171
 172 static int slave_get(struct snd_kcontrol *kcontrol,
 173                      struct snd_ctl_elem_value *ucontrol)
 174 {
 175         struct link_slave *slave = snd_kcontrol_chip(kcontrol);
 176         return slave_get_val(slave, ucontrol);
 177 }
 178
 179 static int slave_put(struct snd_kcontrol *kcontrol,
 180                      struct snd_ctl_elem_value *ucontrol)
 181 {
 182         struct link_slave *slave = snd_kcontrol_chip(kcontrol);
 183         int err, ch, changed = 0;
 184
 185         err = slave_init(slave);
 186         if (err < 0)
 187                 return err;
 188         for (ch = 0; ch < slave->info.count; ch++) {
 189                 if (slave->vals[ch] != ucontrol->value.integer.value[ch]) {
 190                         changed = 1;
 191                         slave->vals[ch] = ucontrol->value.integer.value[ch];
 192                 }
 193         }
 194         if (!changed)
 195                 return 0;
 196         return slave_put_val(slave, ucontrol);
 197 }
 198
 199 static int slave_tlv_cmd(struct snd_kcontrol *kcontrol,
 200                          int op_flag, unsigned int size,
 201                          unsigned int __user *tlv)
 202 {
 203         struct link_slave *slave = snd_kcontrol_chip(kcontrol);
 204         /* FIXME: this assumes that the max volume is 0 dB */
 205         return slave->slave.tlv.c(&slave->slave, op_flag, size, tlv);
 206 }
 207
 208 static void slave_free(struct snd_kcontrol *kcontrol)
 209 {
 210         struct link_slave *slave = snd_kcontrol_chip(kcontrol);
 211         if (slave->slave.private_free)
 212                 slave->slave.private_free(&slave->slave);
 213         if (slave->master)
 214                 list_del(&slave->list);
 215         kfree(slave);
 216 }
 217
 218 /*
 219  * Add a slave control to the group with the given master control
 220  *
 221  * All slaves must be the same type (returning the same information
 222  * via info callback).  The fucntion doesn't check it, so it's your
 223  * responsibility.
 224  *
 225  * Also, some additional limitations:
 226  * - at most two channels
 227  * - logarithmic volume control (dB level), no linear volume
 228  * - master can only attenuate the volume, no gain
 229  */
 230 int snd_ctl_add_slave(struct snd_kcontrol *master, struct snd_kcontrol *slave)
 231 {
 232         struct link_master *master_link = snd_kcontrol_chip(master);
 233         struct link_slave *srec;
 234
 235         srec = kzalloc(sizeof(*srec) +
 236                        slave->count * sizeof(*slave->vd), GFP_KERNEL);
 237         if (!srec)
 238                 return -ENOMEM;
 239         srec->slave = *slave;
 240         memcpy(srec->slave.vd, slave->vd, slave->count * sizeof(*slave->vd));
 241         srec->master = master_link;
 242
 243         /* override callbacks */
 244         slave->info = slave_info;
 245         slave->get = slave_get;
 246         slave->put = slave_put;
 247         if (slave->vd[0].access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK)
 248                 slave->tlv.c = slave_tlv_cmd;
 249         slave->private_data = srec;
 250         slave->private_free = slave_free;
 251
 252         list_add_tail(&srec->list, &master_link->slaves);
 253         return 0;
 254 }
 255
 256 /*
 257  * ctl callbacks for master controls
 258  */
 259 static int master_info(struct snd_kcontrol *kcontrol,
 260                       struct snd_ctl_elem_info *uinfo)
 261 {
 262         struct link_master *master = snd_kcontrol_chip(kcontrol);
 263         int ret;
 264
 265         ret = master_init(master);
 266         if (ret < 0)
 267                 return ret;
 268         uinfo->type = master->info.type;
 269         uinfo->count = master->info.count;
 270         uinfo->value.integer.min = master->info.min_val;
 271         uinfo->value.integer.max = master->info.max_val;
 272         return 0;
 273 }
 274
 275 static int master_get(struct snd_kcontrol *kcontrol,
 276                       struct snd_ctl_elem_value *ucontrol)
 277 {
 278         struct link_master *master = snd_kcontrol_chip(kcontrol);
 279         int err = master_init(master);
 280         if (err < 0)
 281                 return err;
 282         ucontrol->value.integer.value[0] = master->val;
 283         return 0;
 284 }
 285
 286 static int master_put(struct snd_kcontrol *kcontrol,
 287                       struct snd_ctl_elem_value *ucontrol)
 288 {
 289         struct link_master *master = snd_kcontrol_chip(kcontrol);
 290         struct link_slave *slave;
 291         struct snd_ctl_elem_value *uval;
 292         int err, old_val;
 293
 294         err = master_init(master);
 295         if (err < 0)
 296                 return err;
 297         old_val = master->val;
 298         if (ucontrol->value.integer.value[0] == old_val)
 299                 return 0;
 300
 301         uval = kmalloc(sizeof(*uval), GFP_KERNEL);
 302         if (!uval)
 303                 return -ENOMEM;
 304         list_for_each_entry(slave, &master->slaves, list) {
 305                 master->val = old_val;
 306                 uval->id = slave->slave.id;
 307                 slave_get_val(slave, uval);
 308                 master->val = ucontrol->value.integer.value[0];
 309                 slave_put_val(slave, uval);
 310         }
 311         kfree(uval);
 312         return 1;
 313 }
 314
 315 static void master_free(struct snd_kcontrol *kcontrol)
 316 {
 317         struct link_master *master = snd_kcontrol_chip(kcontrol);
 318         struct link_slave *slave;
 319
 320         list_for_each_entry(slave, &master->slaves, list)
 321                 slave->master = NULL;
 322         kfree(master);
 323 }
 324
 325
 326 /*
 327  * Create a virtual master control with the given name
 328  */
 329 struct snd_kcontrol *snd_ctl_make_virtual_master(char *name,
 330                                                  const unsigned int *tlv)
 331 {
 332         struct link_master *master;
 333         struct snd_kcontrol *kctl;
 334         struct snd_kcontrol_new knew;
 335
 336         memset(&knew, 0, sizeof(knew));
 337         knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
 338         knew.name = name;
 339         knew.info = master_info;
 340
 341         master = kzalloc(sizeof(*master), GFP_KERNEL);
 342         if (!master)
 343                 return NULL;
 344         INIT_LIST_HEAD(&master->slaves);
 345
 346         kctl = snd_ctl_new1(&knew, master);
 347         if (!kctl) {
 348                 kfree(master);
 349                 return NULL;
 350         }
 351         /* override some callbacks */
 352         kctl->info = master_info;
 353         kctl->get = master_get;
 354         kctl->put = master_put;
 355         kctl->private_free = master_free;
 356
 357         /* additional (constant) TLV read */
 358         if (tlv) {
 359                 /* FIXME: this assumes that the max volume is 0 dB */
 360                 kctl->vd[0].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ;
 361                 kctl->tlv.p = tlv;
 362         }
 363         return kctl;
 364 }