1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Hardware dependent layer 4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz> 5 */ 6 7 #include <linux/major.h> 8 #include <linux/init.h> 9 #include <linux/slab.h> 10 #include <linux/time.h> 11 #include <linux/mutex.h> 12 #include <linux/module.h> 13 #include <linux/sched/signal.h> 14 #include <sound/core.h> 15 #include <sound/control.h> 16 #include <sound/minors.h> 17 #include <sound/hwdep.h> 18 #include <sound/info.h> 19 20 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>"); 21 MODULE_DESCRIPTION("Hardware dependent layer"); 22 MODULE_LICENSE("GPL"); 23 24 static LIST_HEAD(snd_hwdep_devices); 25 static DEFINE_MUTEX(register_mutex); 26 27 static int snd_hwdep_dev_free(struct snd_device *device); 28 static int snd_hwdep_dev_register(struct snd_device *device); 29 static int snd_hwdep_dev_disconnect(struct snd_device *device); 30 31 32 static struct snd_hwdep *snd_hwdep_search(struct snd_card *card, int device) 33 { 34 struct snd_hwdep *hwdep; 35 36 list_for_each_entry(hwdep, &snd_hwdep_devices, list) 37 if (hwdep->card == card && hwdep->device == device) 38 return hwdep; 39 return NULL; 40 } 41 42 static loff_t snd_hwdep_llseek(struct file * file, loff_t offset, int orig) 43 { 44 struct snd_hwdep *hw = file->private_data; 45 if (hw->ops.llseek) 46 return hw->ops.llseek(hw, file, offset, orig); 47 return -ENXIO; 48 } 49 50 static ssize_t snd_hwdep_read(struct file * file, char __user *buf, 51 size_t count, loff_t *offset) 52 { 53 struct snd_hwdep *hw = file->private_data; 54 if (hw->ops.read) 55 return hw->ops.read(hw, buf, count, offset); 56 return -ENXIO; 57 } 58 59 static ssize_t snd_hwdep_write(struct file * file, const char __user *buf, 60 size_t count, loff_t *offset) 61 { 62 struct snd_hwdep *hw = file->private_data; 63 if (hw->ops.write) 64 return hw->ops.write(hw, buf, count, offset); 65 return -ENXIO; 66 } 67 68 static int snd_hwdep_open(struct inode *inode, struct file * file) 69 { 70 int major = imajor(inode); 71 struct snd_hwdep *hw; 72 int err; 73 wait_queue_entry_t wait; 74 75 if (major == snd_major) { 76 hw = snd_lookup_minor_data(iminor(inode), 77 SNDRV_DEVICE_TYPE_HWDEP); 78 #ifdef CONFIG_SND_OSSEMUL 79 } else if (major == SOUND_MAJOR) { 80 hw = snd_lookup_oss_minor_data(iminor(inode), 81 SNDRV_OSS_DEVICE_TYPE_DMFM); 82 #endif 83 } else 84 return -ENXIO; 85 if (hw == NULL) 86 return -ENODEV; 87 88 if (!try_module_get(hw->card->module)) { 89 snd_card_unref(hw->card); 90 return -EFAULT; 91 } 92 93 init_waitqueue_entry(&wait, current); 94 add_wait_queue(&hw->open_wait, &wait); 95 mutex_lock(&hw->open_mutex); 96 while (1) { 97 if (hw->exclusive && hw->used > 0) { 98 err = -EBUSY; 99 break; 100 } 101 if (!hw->ops.open) { 102 err = 0; 103 break; 104 } 105 err = hw->ops.open(hw, file); 106 if (err >= 0) 107 break; 108 if (err == -EAGAIN) { 109 if (file->f_flags & O_NONBLOCK) { 110 err = -EBUSY; 111 break; 112 } 113 } else 114 break; 115 set_current_state(TASK_INTERRUPTIBLE); 116 mutex_unlock(&hw->open_mutex); 117 schedule(); 118 mutex_lock(&hw->open_mutex); 119 if (hw->card->shutdown) { 120 err = -ENODEV; 121 break; 122 } 123 if (signal_pending(current)) { 124 err = -ERESTARTSYS; 125 break; 126 } 127 } 128 remove_wait_queue(&hw->open_wait, &wait); 129 if (err >= 0) { 130 err = snd_card_file_add(hw->card, file); 131 if (err >= 0) { 132 file->private_data = hw; 133 hw->used++; 134 } else { 135 if (hw->ops.release) 136 hw->ops.release(hw, file); 137 } 138 } 139 mutex_unlock(&hw->open_mutex); 140 if (err < 0) 141 module_put(hw->card->module); 142 snd_card_unref(hw->card); 143 return err; 144 } 145 146 static int snd_hwdep_release(struct inode *inode, struct file * file) 147 { 148 int err = 0; 149 struct snd_hwdep *hw = file->private_data; 150 struct module *mod = hw->card->module; 151 152 mutex_lock(&hw->open_mutex); 153 if (hw->ops.release) 154 err = hw->ops.release(hw, file); 155 if (hw->used > 0) 156 hw->used--; 157 mutex_unlock(&hw->open_mutex); 158 wake_up(&hw->open_wait); 159 160 snd_card_file_remove(hw->card, file); 161 module_put(mod); 162 return err; 163 } 164 165 static __poll_t snd_hwdep_poll(struct file * file, poll_table * wait) 166 { 167 struct snd_hwdep *hw = file->private_data; 168 if (hw->ops.poll) 169 return hw->ops.poll(hw, file, wait); 170 return 0; 171 } 172 173 static int snd_hwdep_info(struct snd_hwdep *hw, 174 struct snd_hwdep_info __user *_info) 175 { 176 struct snd_hwdep_info info; 177 178 memset(&info, 0, sizeof(info)); 179 info.card = hw->card->number; 180 strlcpy(info.id, hw->id, sizeof(info.id)); 181 strlcpy(info.name, hw->name, sizeof(info.name)); 182 info.iface = hw->iface; 183 if (copy_to_user(_info, &info, sizeof(info))) 184 return -EFAULT; 185 return 0; 186 } 187 188 static int snd_hwdep_dsp_status(struct snd_hwdep *hw, 189 struct snd_hwdep_dsp_status __user *_info) 190 { 191 struct snd_hwdep_dsp_status info; 192 int err; 193 194 if (! hw->ops.dsp_status) 195 return -ENXIO; 196 memset(&info, 0, sizeof(info)); 197 info.dsp_loaded = hw->dsp_loaded; 198 if ((err = hw->ops.dsp_status(hw, &info)) < 0) 199 return err; 200 if (copy_to_user(_info, &info, sizeof(info))) 201 return -EFAULT; 202 return 0; 203 } 204 205 static int snd_hwdep_dsp_load(struct snd_hwdep *hw, 206 struct snd_hwdep_dsp_image *info) 207 { 208 int err; 209 210 if (! hw->ops.dsp_load) 211 return -ENXIO; 212 if (info->index >= 32) 213 return -EINVAL; 214 /* check whether the dsp was already loaded */ 215 if (hw->dsp_loaded & (1u << info->index)) 216 return -EBUSY; 217 err = hw->ops.dsp_load(hw, info); 218 if (err < 0) 219 return err; 220 hw->dsp_loaded |= (1u << info->index); 221 return 0; 222 } 223 224 static int snd_hwdep_dsp_load_user(struct snd_hwdep *hw, 225 struct snd_hwdep_dsp_image __user *_info) 226 { 227 struct snd_hwdep_dsp_image info = {}; 228 229 if (copy_from_user(&info, _info, sizeof(info))) 230 return -EFAULT; 231 return snd_hwdep_dsp_load(hw, &info); 232 } 233 234 235 static long snd_hwdep_ioctl(struct file * file, unsigned int cmd, 236 unsigned long arg) 237 { 238 struct snd_hwdep *hw = file->private_data; 239 void __user *argp = (void __user *)arg; 240 switch (cmd) { 241 case SNDRV_HWDEP_IOCTL_PVERSION: 242 return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp); 243 case SNDRV_HWDEP_IOCTL_INFO: 244 return snd_hwdep_info(hw, argp); 245 case SNDRV_HWDEP_IOCTL_DSP_STATUS: 246 return snd_hwdep_dsp_status(hw, argp); 247 case SNDRV_HWDEP_IOCTL_DSP_LOAD: 248 return snd_hwdep_dsp_load_user(hw, argp); 249 } 250 if (hw->ops.ioctl) 251 return hw->ops.ioctl(hw, file, cmd, arg); 252 return -ENOTTY; 253 } 254 255 static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma) 256 { 257 struct snd_hwdep *hw = file->private_data; 258 if (hw->ops.mmap) 259 return hw->ops.mmap(hw, file, vma); 260 return -ENXIO; 261 } 262 263 static int snd_hwdep_control_ioctl(struct snd_card *card, 264 struct snd_ctl_file * control, 265 unsigned int cmd, unsigned long arg) 266 { 267 switch (cmd) { 268 case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE: 269 { 270 int device; 271 272 if (get_user(device, (int __user *)arg)) 273 return -EFAULT; 274 mutex_lock(®ister_mutex); 275 276 if (device < 0) 277 device = 0; 278 else if (device < SNDRV_MINOR_HWDEPS) 279 device++; 280 else 281 device = SNDRV_MINOR_HWDEPS; 282 283 while (device < SNDRV_MINOR_HWDEPS) { 284 if (snd_hwdep_search(card, device)) 285 break; 286 device++; 287 } 288 if (device >= SNDRV_MINOR_HWDEPS) 289 device = -1; 290 mutex_unlock(®ister_mutex); 291 if (put_user(device, (int __user *)arg)) 292 return -EFAULT; 293 return 0; 294 } 295 case SNDRV_CTL_IOCTL_HWDEP_INFO: 296 { 297 struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg; 298 int device, err; 299 struct snd_hwdep *hwdep; 300 301 if (get_user(device, &info->device)) 302 return -EFAULT; 303 mutex_lock(®ister_mutex); 304 hwdep = snd_hwdep_search(card, device); 305 if (hwdep) 306 err = snd_hwdep_info(hwdep, info); 307 else 308 err = -ENXIO; 309 mutex_unlock(®ister_mutex); 310 return err; 311 } 312 } 313 return -ENOIOCTLCMD; 314 } 315 316 #ifdef CONFIG_COMPAT 317 #include "hwdep_compat.c" 318 #else 319 #define snd_hwdep_ioctl_compat NULL 320 #endif 321 322 /* 323 324 */ 325 326 static const struct file_operations snd_hwdep_f_ops = 327 { 328 .owner = THIS_MODULE, 329 .llseek = snd_hwdep_llseek, 330 .read = snd_hwdep_read, 331 .write = snd_hwdep_write, 332 .open = snd_hwdep_open, 333 .release = snd_hwdep_release, 334 .poll = snd_hwdep_poll, 335 .unlocked_ioctl = snd_hwdep_ioctl, 336 .compat_ioctl = snd_hwdep_ioctl_compat, 337 .mmap = snd_hwdep_mmap, 338 }; 339 340 static void release_hwdep_device(struct device *dev) 341 { 342 kfree(container_of(dev, struct snd_hwdep, dev)); 343 } 344 345 /** 346 * snd_hwdep_new - create a new hwdep instance 347 * @card: the card instance 348 * @id: the id string 349 * @device: the device index (zero-based) 350 * @rhwdep: the pointer to store the new hwdep instance 351 * 352 * Creates a new hwdep instance with the given index on the card. 353 * The callbacks (hwdep->ops) must be set on the returned instance 354 * after this call manually by the caller. 355 * 356 * Return: Zero if successful, or a negative error code on failure. 357 */ 358 int snd_hwdep_new(struct snd_card *card, char *id, int device, 359 struct snd_hwdep **rhwdep) 360 { 361 struct snd_hwdep *hwdep; 362 int err; 363 static const struct snd_device_ops ops = { 364 .dev_free = snd_hwdep_dev_free, 365 .dev_register = snd_hwdep_dev_register, 366 .dev_disconnect = snd_hwdep_dev_disconnect, 367 }; 368 369 if (snd_BUG_ON(!card)) 370 return -ENXIO; 371 if (rhwdep) 372 *rhwdep = NULL; 373 hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL); 374 if (!hwdep) 375 return -ENOMEM; 376 377 init_waitqueue_head(&hwdep->open_wait); 378 mutex_init(&hwdep->open_mutex); 379 hwdep->card = card; 380 hwdep->device = device; 381 if (id) 382 strlcpy(hwdep->id, id, sizeof(hwdep->id)); 383 384 snd_device_initialize(&hwdep->dev, card); 385 hwdep->dev.release = release_hwdep_device; 386 dev_set_name(&hwdep->dev, "hwC%iD%i", card->number, device); 387 #ifdef CONFIG_SND_OSSEMUL 388 hwdep->oss_type = -1; 389 #endif 390 391 err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops); 392 if (err < 0) { 393 put_device(&hwdep->dev); 394 return err; 395 } 396 397 if (rhwdep) 398 *rhwdep = hwdep; 399 return 0; 400 } 401 EXPORT_SYMBOL(snd_hwdep_new); 402 403 static int snd_hwdep_dev_free(struct snd_device *device) 404 { 405 struct snd_hwdep *hwdep = device->device_data; 406 if (!hwdep) 407 return 0; 408 if (hwdep->private_free) 409 hwdep->private_free(hwdep); 410 put_device(&hwdep->dev); 411 return 0; 412 } 413 414 static int snd_hwdep_dev_register(struct snd_device *device) 415 { 416 struct snd_hwdep *hwdep = device->device_data; 417 struct snd_card *card = hwdep->card; 418 int err; 419 420 mutex_lock(®ister_mutex); 421 if (snd_hwdep_search(card, hwdep->device)) { 422 mutex_unlock(®ister_mutex); 423 return -EBUSY; 424 } 425 list_add_tail(&hwdep->list, &snd_hwdep_devices); 426 err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP, 427 hwdep->card, hwdep->device, 428 &snd_hwdep_f_ops, hwdep, &hwdep->dev); 429 if (err < 0) { 430 dev_err(&hwdep->dev, "unable to register\n"); 431 list_del(&hwdep->list); 432 mutex_unlock(®ister_mutex); 433 return err; 434 } 435 436 #ifdef CONFIG_SND_OSSEMUL 437 hwdep->ossreg = 0; 438 if (hwdep->oss_type >= 0) { 439 if (hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM && 440 hwdep->device) 441 dev_warn(&hwdep->dev, 442 "only hwdep device 0 can be registered as OSS direct FM device!\n"); 443 else if (snd_register_oss_device(hwdep->oss_type, 444 card, hwdep->device, 445 &snd_hwdep_f_ops, hwdep) < 0) 446 dev_warn(&hwdep->dev, 447 "unable to register OSS compatibility device\n"); 448 else 449 hwdep->ossreg = 1; 450 } 451 #endif 452 mutex_unlock(®ister_mutex); 453 return 0; 454 } 455 456 static int snd_hwdep_dev_disconnect(struct snd_device *device) 457 { 458 struct snd_hwdep *hwdep = device->device_data; 459 460 if (snd_BUG_ON(!hwdep)) 461 return -ENXIO; 462 mutex_lock(®ister_mutex); 463 if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) { 464 mutex_unlock(®ister_mutex); 465 return -EINVAL; 466 } 467 mutex_lock(&hwdep->open_mutex); 468 wake_up(&hwdep->open_wait); 469 #ifdef CONFIG_SND_OSSEMUL 470 if (hwdep->ossreg) 471 snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device); 472 #endif 473 snd_unregister_device(&hwdep->dev); 474 list_del_init(&hwdep->list); 475 mutex_unlock(&hwdep->open_mutex); 476 mutex_unlock(®ister_mutex); 477 return 0; 478 } 479 480 #ifdef CONFIG_SND_PROC_FS 481 /* 482 * Info interface 483 */ 484 485 static void snd_hwdep_proc_read(struct snd_info_entry *entry, 486 struct snd_info_buffer *buffer) 487 { 488 struct snd_hwdep *hwdep; 489 490 mutex_lock(®ister_mutex); 491 list_for_each_entry(hwdep, &snd_hwdep_devices, list) 492 snd_iprintf(buffer, "%02i-%02i: %s\n", 493 hwdep->card->number, hwdep->device, hwdep->name); 494 mutex_unlock(®ister_mutex); 495 } 496 497 static struct snd_info_entry *snd_hwdep_proc_entry; 498 499 static void __init snd_hwdep_proc_init(void) 500 { 501 struct snd_info_entry *entry; 502 503 if ((entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL)) != NULL) { 504 entry->c.text.read = snd_hwdep_proc_read; 505 if (snd_info_register(entry) < 0) { 506 snd_info_free_entry(entry); 507 entry = NULL; 508 } 509 } 510 snd_hwdep_proc_entry = entry; 511 } 512 513 static void __exit snd_hwdep_proc_done(void) 514 { 515 snd_info_free_entry(snd_hwdep_proc_entry); 516 } 517 #else /* !CONFIG_SND_PROC_FS */ 518 #define snd_hwdep_proc_init() 519 #define snd_hwdep_proc_done() 520 #endif /* CONFIG_SND_PROC_FS */ 521 522 523 /* 524 * ENTRY functions 525 */ 526 527 static int __init alsa_hwdep_init(void) 528 { 529 snd_hwdep_proc_init(); 530 snd_ctl_register_ioctl(snd_hwdep_control_ioctl); 531 snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl); 532 return 0; 533 } 534 535 static void __exit alsa_hwdep_exit(void) 536 { 537 snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl); 538 snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl); 539 snd_hwdep_proc_done(); 540 } 541 542 module_init(alsa_hwdep_init) 543 module_exit(alsa_hwdep_exit) 544