1 /* mixer.c 2 ** 3 ** Copyright 2011, The Android Open Source Project 4 ** 5 ** Redistribution and use in source and binary forms, with or without 6 ** modification, are permitted provided that the following conditions are met: 7 ** * Redistributions of source code must retain the above copyright 8 ** notice, this list of conditions and the following disclaimer. 9 ** * Redistributions in binary form must reproduce the above copyright 10 ** notice, this list of conditions and the following disclaimer in the 11 ** documentation and/or other materials provided with the distribution. 12 ** * Neither the name of The Android Open Source Project nor the names of 13 ** its contributors may be used to endorse or promote products derived 14 ** from this software without specific prior written permission. 15 ** 16 ** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND 17 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 ** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE 20 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 22 ** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 23 ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 26 ** DAMAGE. 27 */ 28 29 #include <stdio.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <unistd.h> 33 #include <fcntl.h> 34 #include <errno.h> 35 #include <ctype.h> 36 37 #include <linux/ioctl.h> 38 #define __force 39 #define __bitwise 40 #define __user 41 #include <sound/asound.h> 42 43 #include <tinyalsa/asoundlib.h> 44 45 struct mixer_ctl { 46 struct mixer *mixer; 47 struct snd_ctl_elem_info *info; 48 char **ename; 49 }; 50 51 struct mixer { 52 int fd; 53 struct snd_ctl_elem_info *info; 54 struct mixer_ctl *ctl; 55 unsigned int count; 56 }; 57 58 void mixer_close(struct mixer *mixer) 59 { 60 unsigned int n,m; 61 62 if (!mixer) 63 return; 64 65 if (mixer->fd >= 0) 66 close(mixer->fd); 67 68 if (mixer->ctl) { 69 for (n = 0; n < mixer->count; n++) { 70 if (mixer->ctl[n].ename) { 71 unsigned int max = mixer->ctl[n].info->value.enumerated.items; 72 for (m = 0; m < max; m++) 73 free(mixer->ctl[n].ename[m]); 74 free(mixer->ctl[n].ename); 75 } 76 } 77 free(mixer->ctl); 78 } 79 80 if (mixer->info) 81 free(mixer->info); 82 83 free(mixer); 84 85 /* TODO: verify frees */ 86 } 87 88 struct mixer *mixer_open(unsigned int card) 89 { 90 struct snd_ctl_elem_list elist; 91 struct snd_ctl_elem_info tmp; 92 struct snd_ctl_elem_id *eid = NULL; 93 struct mixer *mixer = NULL; 94 unsigned int n, m; 95 int fd; 96 char fn[256]; 97 98 snprintf(fn, sizeof(fn), "/dev/snd/controlC%u", card); 99 fd = open(fn, O_RDWR); 100 if (fd < 0) 101 return 0; 102 103 memset(&elist, 0, sizeof(elist)); 104 if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &elist) < 0) 105 goto fail; 106 107 mixer = calloc(1, sizeof(*mixer)); 108 if (!mixer) 109 goto fail; 110 111 mixer->ctl = calloc(elist.count, sizeof(struct mixer_ctl)); 112 mixer->info = calloc(elist.count, sizeof(struct snd_ctl_elem_info)); 113 if (!mixer->ctl || !mixer->info) 114 goto fail; 115 116 eid = calloc(elist.count, sizeof(struct snd_ctl_elem_id)); 117 if (!eid) 118 goto fail; 119 120 mixer->count = elist.count; 121 mixer->fd = fd; 122 elist.space = mixer->count; 123 elist.pids = eid; 124 if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &elist) < 0) 125 goto fail; 126 127 for (n = 0; n < mixer->count; n++) { 128 struct snd_ctl_elem_info *ei = mixer->info + n; 129 ei->id.numid = eid[n].numid; 130 if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, ei) < 0) 131 goto fail; 132 mixer->ctl[n].info = ei; 133 mixer->ctl[n].mixer = mixer; 134 if (ei->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) { 135 char **enames = calloc(ei->value.enumerated.items, sizeof(char*)); 136 if (!enames) 137 goto fail; 138 mixer->ctl[n].ename = enames; 139 for (m = 0; m < ei->value.enumerated.items; m++) { 140 memset(&tmp, 0, sizeof(tmp)); 141 tmp.id.numid = ei->id.numid; 142 tmp.value.enumerated.item = m; 143 if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, &tmp) < 0) 144 goto fail; 145 enames[m] = strdup(tmp.value.enumerated.name); 146 if (!enames[m]) 147 goto fail; 148 } 149 } 150 } 151 152 free(eid); 153 return mixer; 154 155 fail: 156 /* TODO: verify frees in failure case */ 157 if (eid) 158 free(eid); 159 if (mixer) 160 mixer_close(mixer); 161 else if (fd >= 0) 162 close(fd); 163 return 0; 164 } 165 166 unsigned int mixer_get_num_ctls(struct mixer *mixer) 167 { 168 if (!mixer) 169 return 0; 170 171 return mixer->count; 172 } 173 174 struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id) 175 { 176 if (mixer && (id < mixer->count)) 177 return mixer->ctl + id; 178 179 return NULL; 180 } 181 182 struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name) 183 { 184 unsigned int n; 185 186 if (!mixer) 187 return NULL; 188 189 for (n = 0; n < mixer->count; n++) 190 if (!strcmp(name, (char*) mixer->info[n].id.name)) 191 return mixer->ctl + n; 192 193 return NULL; 194 } 195 196 const char *mixer_ctl_get_name(struct mixer_ctl *ctl) 197 { 198 if (!ctl) 199 return NULL; 200 201 return (const char *)ctl->info->id.name; 202 } 203 204 enum mixer_ctl_type mixer_ctl_get_type(struct mixer_ctl *ctl) 205 { 206 if (!ctl) 207 return MIXER_CTL_TYPE_UNKNOWN; 208 209 switch (ctl->info->type) { 210 case SNDRV_CTL_ELEM_TYPE_BOOLEAN: return MIXER_CTL_TYPE_BOOL; 211 case SNDRV_CTL_ELEM_TYPE_INTEGER: return MIXER_CTL_TYPE_INT; 212 case SNDRV_CTL_ELEM_TYPE_ENUMERATED: return MIXER_CTL_TYPE_ENUM; 213 case SNDRV_CTL_ELEM_TYPE_BYTES: return MIXER_CTL_TYPE_BYTE; 214 case SNDRV_CTL_ELEM_TYPE_IEC958: return MIXER_CTL_TYPE_IEC958; 215 case SNDRV_CTL_ELEM_TYPE_INTEGER64: return MIXER_CTL_TYPE_INT64; 216 default: return MIXER_CTL_TYPE_UNKNOWN; 217 }; 218 } 219 220 const char *mixer_ctl_get_type_string(struct mixer_ctl *ctl) 221 { 222 if (!ctl) 223 return ""; 224 225 switch (ctl->info->type) { 226 case SNDRV_CTL_ELEM_TYPE_BOOLEAN: return "BOOL"; 227 case SNDRV_CTL_ELEM_TYPE_INTEGER: return "INT"; 228 case SNDRV_CTL_ELEM_TYPE_ENUMERATED: return "ENUM"; 229 case SNDRV_CTL_ELEM_TYPE_BYTES: return "BYTE"; 230 case SNDRV_CTL_ELEM_TYPE_IEC958: return "IEC958"; 231 case SNDRV_CTL_ELEM_TYPE_INTEGER64: return "INT64"; 232 default: return "Unknown"; 233 }; 234 } 235 236 unsigned int mixer_ctl_get_num_values(struct mixer_ctl *ctl) 237 { 238 if (!ctl) 239 return 0; 240 241 return ctl->info->count; 242 } 243 244 static int percent_to_int(struct snd_ctl_elem_info *ei, int percent) 245 { 246 int range; 247 248 if (percent > 100) 249 percent = 100; 250 else if (percent < 0) 251 percent = 0; 252 253 range = (ei->value.integer.max - ei->value.integer.min); 254 255 return ei->value.integer.min + (range * percent) / 100; 256 } 257 258 static int int_to_percent(struct snd_ctl_elem_info *ei, int value) 259 { 260 int range = (ei->value.integer.max - ei->value.integer.min); 261 262 if (range == 0) 263 return 0; 264 265 return ((value - ei->value.integer.min) / range) * 100; 266 } 267 268 int mixer_ctl_get_percent(struct mixer_ctl *ctl, unsigned int id) 269 { 270 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER)) 271 return -EINVAL; 272 273 return int_to_percent(ctl->info, mixer_ctl_get_value(ctl, id)); 274 } 275 276 int mixer_ctl_set_percent(struct mixer_ctl *ctl, unsigned int id, int percent) 277 { 278 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER)) 279 return -EINVAL; 280 281 return mixer_ctl_set_value(ctl, id, percent_to_int(ctl->info, percent)); 282 } 283 284 int mixer_ctl_get_value(struct mixer_ctl *ctl, unsigned int id) 285 { 286 struct snd_ctl_elem_value ev; 287 int ret; 288 289 if (!ctl || (id >= ctl->info->count)) 290 return -EINVAL; 291 292 memset(&ev, 0, sizeof(ev)); 293 ev.id.numid = ctl->info->id.numid; 294 ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev); 295 if (ret < 0) 296 return ret; 297 298 switch (ctl->info->type) { 299 case SNDRV_CTL_ELEM_TYPE_BOOLEAN: 300 return !!ev.value.integer.value[id]; 301 302 case SNDRV_CTL_ELEM_TYPE_INTEGER: 303 return ev.value.integer.value[id]; 304 305 case SNDRV_CTL_ELEM_TYPE_ENUMERATED: 306 return ev.value.enumerated.item[id]; 307 308 case SNDRV_CTL_ELEM_TYPE_BYTES: 309 return ev.value.bytes.data[id]; 310 311 default: 312 return -EINVAL; 313 } 314 315 return 0; 316 } 317 318 int mixer_ctl_set_value(struct mixer_ctl *ctl, unsigned int id, int value) 319 { 320 struct snd_ctl_elem_value ev; 321 int ret; 322 323 if (!ctl || (id >= ctl->info->count)) 324 return -EINVAL; 325 326 memset(&ev, 0, sizeof(ev)); 327 ev.id.numid = ctl->info->id.numid; 328 ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev); 329 if (ret < 0) 330 return ret; 331 332 switch (ctl->info->type) { 333 case SNDRV_CTL_ELEM_TYPE_BOOLEAN: 334 ev.value.integer.value[id] = !!value; 335 break; 336 337 case SNDRV_CTL_ELEM_TYPE_INTEGER: 338 ev.value.integer.value[id] = value; 339 break; 340 341 case SNDRV_CTL_ELEM_TYPE_ENUMERATED: 342 ev.value.enumerated.item[id] = value; 343 break; 344 345 default: 346 return -EINVAL; 347 } 348 349 return ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev); 350 } 351 352 int mixer_ctl_get_range_min(struct mixer_ctl *ctl) 353 { 354 int ret; 355 356 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER)) 357 return -EINVAL; 358 359 return ctl->info->value.integer.min; 360 } 361 362 int mixer_ctl_get_range_max(struct mixer_ctl *ctl) 363 { 364 int ret; 365 366 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_INTEGER)) 367 return -EINVAL; 368 369 return ctl->info->value.integer.max; 370 } 371 372 unsigned int mixer_ctl_get_num_enums(struct mixer_ctl *ctl) 373 { 374 if (!ctl) 375 return 0; 376 377 return ctl->info->value.enumerated.items; 378 } 379 380 const char *mixer_ctl_get_enum_string(struct mixer_ctl *ctl, 381 unsigned int enum_id) 382 { 383 int ret; 384 385 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_ENUMERATED) || 386 (enum_id >= ctl->info->value.enumerated.items)) 387 return NULL; 388 389 return (const char *)ctl->ename[enum_id]; 390 } 391 392 int mixer_ctl_set_enum_by_string(struct mixer_ctl *ctl, const char *string) 393 { 394 unsigned int i, num_enums; 395 struct snd_ctl_elem_value ev; 396 int ret; 397 398 if (!ctl || (ctl->info->type != SNDRV_CTL_ELEM_TYPE_ENUMERATED)) 399 return -EINVAL; 400 401 num_enums = ctl->info->value.enumerated.items; 402 for (i = 0; i < num_enums; i++) { 403 if (!strcmp(string, ctl->ename[i])) { 404 memset(&ev, 0, sizeof(ev)); 405 ev.value.enumerated.item[0] = i; 406 ev.id.numid = ctl->info->id.numid; 407 ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev); 408 if (ret < 0) 409 return ret; 410 return 0; 411 } 412 } 413 414 return -EINVAL; 415 } 416 417
