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 20MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>"); 21MODULE_DESCRIPTION("Hardware dependent layer"); 22MODULE_LICENSE("GPL"); 23 24static LIST_HEAD(snd_hwdep_devices); 25static DEFINE_MUTEX(register_mutex); 26 27static int snd_hwdep_dev_free(struct snd_device *device); 28static int snd_hwdep_dev_register(struct snd_device *device); 29static int snd_hwdep_dev_disconnect(struct snd_device *device); 30 31 32static 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 42static 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 50static 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 59static 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 68static 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 146static 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 165static __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 173static 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 strscpy(info.id, hw->id, sizeof(info.id)); 181 strscpy(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 188static 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 err = hw->ops.dsp_status(hw, &info); 199 if (err < 0) 200 return err; 201 if (copy_to_user(_info, &info, sizeof(info))) 202 return -EFAULT; 203 return 0; 204} 205 206static int snd_hwdep_dsp_load(struct snd_hwdep *hw, 207 struct snd_hwdep_dsp_image *info) 208{ 209 int err; 210 211 if (! hw->ops.dsp_load) 212 return -ENXIO; 213 if (info->index >= 32) 214 return -EINVAL; 215 /* check whether the dsp was already loaded */ 216 if (hw->dsp_loaded & (1u << info->index)) 217 return -EBUSY; 218 err = hw->ops.dsp_load(hw, info); 219 if (err < 0) 220 return err; 221 hw->dsp_loaded |= (1u << info->index); 222 return 0; 223} 224 225static int snd_hwdep_dsp_load_user(struct snd_hwdep *hw, 226 struct snd_hwdep_dsp_image __user *_info) 227{ 228 struct snd_hwdep_dsp_image info = {}; 229 230 if (copy_from_user(&info, _info, sizeof(info))) 231 return -EFAULT; 232 return snd_hwdep_dsp_load(hw, &info); 233} 234 235 236static long snd_hwdep_ioctl(struct file * file, unsigned int cmd, 237 unsigned long arg) 238{ 239 struct snd_hwdep *hw = file->private_data; 240 void __user *argp = (void __user *)arg; 241 switch (cmd) { 242 case SNDRV_HWDEP_IOCTL_PVERSION: 243 return put_user(SNDRV_HWDEP_VERSION, (int __user *)argp); 244 case SNDRV_HWDEP_IOCTL_INFO: 245 return snd_hwdep_info(hw, argp); 246 case SNDRV_HWDEP_IOCTL_DSP_STATUS: 247 return snd_hwdep_dsp_status(hw, argp); 248 case SNDRV_HWDEP_IOCTL_DSP_LOAD: 249 return snd_hwdep_dsp_load_user(hw, argp); 250 } 251 if (hw->ops.ioctl) 252 return hw->ops.ioctl(hw, file, cmd, arg); 253 return -ENOTTY; 254} 255 256static int snd_hwdep_mmap(struct file * file, struct vm_area_struct * vma) 257{ 258 struct snd_hwdep *hw = file->private_data; 259 if (hw->ops.mmap) 260 return hw->ops.mmap(hw, file, vma); 261 return -ENXIO; 262} 263 264static int snd_hwdep_control_ioctl(struct snd_card *card, 265 struct snd_ctl_file * control, 266 unsigned int cmd, unsigned long arg) 267{ 268 switch (cmd) { 269 case SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE: 270 { 271 int device; 272 273 if (get_user(device, (int __user *)arg)) 274 return -EFAULT; 275 mutex_lock(®ister_mutex); 276 277 if (device < 0) 278 device = 0; 279 else if (device < SNDRV_MINOR_HWDEPS) 280 device++; 281 else 282 device = SNDRV_MINOR_HWDEPS; 283 284 while (device < SNDRV_MINOR_HWDEPS) { 285 if (snd_hwdep_search(card, device)) 286 break; 287 device++; 288 } 289 if (device >= SNDRV_MINOR_HWDEPS) 290 device = -1; 291 mutex_unlock(®ister_mutex); 292 if (put_user(device, (int __user *)arg)) 293 return -EFAULT; 294 return 0; 295 } 296 case SNDRV_CTL_IOCTL_HWDEP_INFO: 297 { 298 struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg; 299 int device, err; 300 struct snd_hwdep *hwdep; 301 302 if (get_user(device, &info->device)) 303 return -EFAULT; 304 mutex_lock(®ister_mutex); 305 hwdep = snd_hwdep_search(card, device); 306 if (hwdep) 307 err = snd_hwdep_info(hwdep, info); 308 else 309 err = -ENXIO; 310 mutex_unlock(®ister_mutex); 311 return err; 312 } 313 } 314 return -ENOIOCTLCMD; 315} 316 317#ifdef CONFIG_COMPAT 318#include "hwdep_compat.c" 319#else 320#define snd_hwdep_ioctl_compat NULL 321#endif 322 323/* 324 325 */ 326 327static const struct file_operations snd_hwdep_f_ops = 328{ 329 .owner = THIS_MODULE, 330 .llseek = snd_hwdep_llseek, 331 .read = snd_hwdep_read, 332 .write = snd_hwdep_write, 333 .open = snd_hwdep_open, 334 .release = snd_hwdep_release, 335 .poll = snd_hwdep_poll, 336 .unlocked_ioctl = snd_hwdep_ioctl, 337 .compat_ioctl = snd_hwdep_ioctl_compat, 338 .mmap = snd_hwdep_mmap, 339}; 340 341static void snd_hwdep_free(struct snd_hwdep *hwdep) 342{ 343 if (!hwdep) 344 return; 345 if (hwdep->private_free) 346 hwdep->private_free(hwdep); 347 put_device(hwdep->dev); 348 kfree(hwdep); 349} 350 351/** 352 * snd_hwdep_new - create a new hwdep instance 353 * @card: the card instance 354 * @id: the id string 355 * @device: the device index (zero-based) 356 * @rhwdep: the pointer to store the new hwdep instance 357 * 358 * Creates a new hwdep instance with the given index on the card. 359 * The callbacks (hwdep->ops) must be set on the returned instance 360 * after this call manually by the caller. 361 * 362 * Return: Zero if successful, or a negative error code on failure. 363 */ 364int snd_hwdep_new(struct snd_card *card, char *id, int device, 365 struct snd_hwdep **rhwdep) 366{ 367 struct snd_hwdep *hwdep; 368 int err; 369 static const struct snd_device_ops ops = { 370 .dev_free = snd_hwdep_dev_free, 371 .dev_register = snd_hwdep_dev_register, 372 .dev_disconnect = snd_hwdep_dev_disconnect, 373 }; 374 375 if (snd_BUG_ON(!card)) 376 return -ENXIO; 377 if (rhwdep) 378 *rhwdep = NULL; 379 hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL); 380 if (!hwdep) 381 return -ENOMEM; 382 383 init_waitqueue_head(&hwdep->open_wait); 384 mutex_init(&hwdep->open_mutex); 385 hwdep->card = card; 386 hwdep->device = device; 387 if (id) 388 strscpy(hwdep->id, id, sizeof(hwdep->id)); 389 390 err = snd_device_alloc(&hwdep->dev, card); 391 if (err < 0) { 392 snd_hwdep_free(hwdep); 393 return err; 394 } 395 396 dev_set_name(hwdep->dev, "hwC%iD%i", card->number, device); 397#ifdef CONFIG_SND_OSSEMUL 398 hwdep->oss_type = -1; 399#endif 400 401 err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops); 402 if (err < 0) { 403 snd_hwdep_free(hwdep); 404 return err; 405 } 406 407 if (rhwdep) 408 *rhwdep = hwdep; 409 return 0; 410} 411EXPORT_SYMBOL(snd_hwdep_new); 412 413static int snd_hwdep_dev_free(struct snd_device *device) 414{ 415 snd_hwdep_free(device->device_data); 416 return 0; 417} 418 419static int snd_hwdep_dev_register(struct snd_device *device) 420{ 421 struct snd_hwdep *hwdep = device->device_data; 422 struct snd_card *card = hwdep->card; 423 int err; 424 425 mutex_lock(®ister_mutex); 426 if (snd_hwdep_search(card, hwdep->device)) { 427 mutex_unlock(®ister_mutex); 428 return -EBUSY; 429 } 430 list_add_tail(&hwdep->list, &snd_hwdep_devices); 431 err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP, 432 hwdep->card, hwdep->device, 433 &snd_hwdep_f_ops, hwdep, hwdep->dev); 434 if (err < 0) { 435 dev_err(hwdep->dev, "unable to register\n"); 436 list_del(&hwdep->list); 437 mutex_unlock(®ister_mutex); 438 return err; 439 } 440 441#ifdef CONFIG_SND_OSSEMUL 442 hwdep->ossreg = 0; 443 if (hwdep->oss_type >= 0) { 444 if (hwdep->oss_type == SNDRV_OSS_DEVICE_TYPE_DMFM && 445 hwdep->device) 446 dev_warn(hwdep->dev, 447 "only hwdep device 0 can be registered as OSS direct FM device!\n"); 448 else if (snd_register_oss_device(hwdep->oss_type, 449 card, hwdep->device, 450 &snd_hwdep_f_ops, hwdep) < 0) 451 dev_warn(hwdep->dev, 452 "unable to register OSS compatibility device\n"); 453 else 454 hwdep->ossreg = 1; 455 } 456#endif 457 mutex_unlock(®ister_mutex); 458 return 0; 459} 460 461static int snd_hwdep_dev_disconnect(struct snd_device *device) 462{ 463 struct snd_hwdep *hwdep = device->device_data; 464 465 if (snd_BUG_ON(!hwdep)) 466 return -ENXIO; 467 mutex_lock(®ister_mutex); 468 if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) { 469 mutex_unlock(®ister_mutex); 470 return -EINVAL; 471 } 472 mutex_lock(&hwdep->open_mutex); 473 wake_up(&hwdep->open_wait); 474#ifdef CONFIG_SND_OSSEMUL 475 if (hwdep->ossreg) 476 snd_unregister_oss_device(hwdep->oss_type, hwdep->card, hwdep->device); 477#endif 478 snd_unregister_device(hwdep->dev); 479 list_del_init(&hwdep->list); 480 mutex_unlock(&hwdep->open_mutex); 481 mutex_unlock(®ister_mutex); 482 return 0; 483} 484 485#ifdef CONFIG_SND_PROC_FS 486/* 487 * Info interface 488 */ 489 490static void snd_hwdep_proc_read(struct snd_info_entry *entry, 491 struct snd_info_buffer *buffer) 492{ 493 struct snd_hwdep *hwdep; 494 495 mutex_lock(®ister_mutex); 496 list_for_each_entry(hwdep, &snd_hwdep_devices, list) 497 snd_iprintf(buffer, "%02i-%02i: %s\n", 498 hwdep->card->number, hwdep->device, hwdep->name); 499 mutex_unlock(®ister_mutex); 500} 501 502static struct snd_info_entry *snd_hwdep_proc_entry; 503 504static void __init snd_hwdep_proc_init(void) 505{ 506 struct snd_info_entry *entry; 507 508 entry = snd_info_create_module_entry(THIS_MODULE, "hwdep", NULL); 509 if (entry) { 510 entry->c.text.read = snd_hwdep_proc_read; 511 if (snd_info_register(entry) < 0) { 512 snd_info_free_entry(entry); 513 entry = NULL; 514 } 515 } 516 snd_hwdep_proc_entry = entry; 517} 518 519static void __exit snd_hwdep_proc_done(void) 520{ 521 snd_info_free_entry(snd_hwdep_proc_entry); 522} 523#else /* !CONFIG_SND_PROC_FS */ 524#define snd_hwdep_proc_init() 525#define snd_hwdep_proc_done() 526#endif /* CONFIG_SND_PROC_FS */ 527 528 529/* 530 * ENTRY functions 531 */ 532 533static int __init alsa_hwdep_init(void) 534{ 535 snd_hwdep_proc_init(); 536 snd_ctl_register_ioctl(snd_hwdep_control_ioctl); 537 snd_ctl_register_ioctl_compat(snd_hwdep_control_ioctl); 538 return 0; 539} 540 541static void __exit alsa_hwdep_exit(void) 542{ 543 snd_ctl_unregister_ioctl(snd_hwdep_control_ioctl); 544 snd_ctl_unregister_ioctl_compat(snd_hwdep_control_ioctl); 545 snd_hwdep_proc_done(); 546} 547 548module_init(alsa_hwdep_init) 549module_exit(alsa_hwdep_exit) 550