1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * cec-api.c - HDMI Consumer Electronics Control framework - API 4 * 5 * Copyright 2016 Cisco Systems, Inc. and/or its affiliates. All rights reserved. 6 */ 7 8 #include <linux/errno.h> 9 #include <linux/init.h> 10 #include <linux/module.h> 11 #include <linux/kernel.h> 12 #include <linux/kmod.h> 13 #include <linux/ktime.h> 14 #include <linux/slab.h> 15 #include <linux/mm.h> 16 #include <linux/string.h> 17 #include <linux/types.h> 18 #include <linux/uaccess.h> 19 #include <linux/version.h> 20 21 #include <media/cec-pin.h> 22 #include "cec-priv.h" 23 #include "cec-pin-priv.h" 24 25 static inline struct cec_devnode *cec_devnode_data(struct file *filp) 26 { 27 struct cec_fh *fh = filp->private_data; 28 29 return &fh->adap->devnode; 30 } 31 32 /* CEC file operations */ 33 34 static __poll_t cec_poll(struct file *filp, 35 struct poll_table_struct *poll) 36 { 37 struct cec_fh *fh = filp->private_data; 38 struct cec_adapter *adap = fh->adap; 39 __poll_t res = 0; 40 41 poll_wait(filp, &fh->wait, poll); 42 if (!cec_is_registered(adap)) 43 return EPOLLERR | EPOLLHUP | EPOLLPRI; 44 mutex_lock(&adap->lock); 45 if (adap->is_configured && 46 adap->transmit_queue_sz < CEC_MAX_MSG_TX_QUEUE_SZ) 47 res |= EPOLLOUT | EPOLLWRNORM; 48 if (fh->queued_msgs) 49 res |= EPOLLIN | EPOLLRDNORM; 50 if (fh->total_queued_events) 51 res |= EPOLLPRI; 52 mutex_unlock(&adap->lock); 53 return res; 54 } 55 56 static bool cec_is_busy(const struct cec_adapter *adap, 57 const struct cec_fh *fh) 58 { 59 bool valid_initiator = adap->cec_initiator && adap->cec_initiator == fh; 60 bool valid_follower = adap->cec_follower && adap->cec_follower == fh; 61 62 /* 63 * Exclusive initiators and followers can always access the CEC adapter 64 */ 65 if (valid_initiator || valid_follower) 66 return false; 67 /* 68 * All others can only access the CEC adapter if there is no 69 * exclusive initiator and they are in INITIATOR mode. 70 */ 71 return adap->cec_initiator || 72 fh->mode_initiator == CEC_MODE_NO_INITIATOR; 73 } 74 75 static long cec_adap_g_caps(struct cec_adapter *adap, 76 struct cec_caps __user *parg) 77 { 78 struct cec_caps caps = {}; 79 80 strscpy(caps.driver, adap->devnode.dev.parent->driver->name, 81 sizeof(caps.driver)); 82 strscpy(caps.name, adap->name, sizeof(caps.name)); 83 caps.available_log_addrs = adap->available_log_addrs; 84 caps.capabilities = adap->capabilities; 85 caps.version = LINUX_VERSION_CODE; 86 if (copy_to_user(parg, &caps, sizeof(caps))) 87 return -EFAULT; 88 return 0; 89 } 90 91 static long cec_adap_g_phys_addr(struct cec_adapter *adap, 92 __u16 __user *parg) 93 { 94 u16 phys_addr; 95 96 mutex_lock(&adap->lock); 97 phys_addr = adap->phys_addr; 98 mutex_unlock(&adap->lock); 99 if (copy_to_user(parg, &phys_addr, sizeof(phys_addr))) 100 return -EFAULT; 101 return 0; 102 } 103 104 static int cec_validate_phys_addr(u16 phys_addr) 105 { 106 int i; 107 108 if (phys_addr == CEC_PHYS_ADDR_INVALID) 109 return 0; 110 for (i = 0; i < 16; i += 4) 111 if (phys_addr & (0xf << i)) 112 break; 113 if (i == 16) 114 return 0; 115 for (i += 4; i < 16; i += 4) 116 if ((phys_addr & (0xf << i)) == 0) 117 return -EINVAL; 118 return 0; 119 } 120 121 static long cec_adap_s_phys_addr(struct cec_adapter *adap, struct cec_fh *fh, 122 bool block, __u16 __user *parg) 123 { 124 u16 phys_addr; 125 long err; 126 127 if (!(adap->capabilities & CEC_CAP_PHYS_ADDR)) 128 return -ENOTTY; 129 if (copy_from_user(&phys_addr, parg, sizeof(phys_addr))) 130 return -EFAULT; 131 132 err = cec_validate_phys_addr(phys_addr); 133 if (err) 134 return err; 135 mutex_lock(&adap->lock); 136 if (cec_is_busy(adap, fh)) 137 err = -EBUSY; 138 else 139 __cec_s_phys_addr(adap, phys_addr, block); 140 mutex_unlock(&adap->lock); 141 return err; 142 } 143 144 static long cec_adap_g_log_addrs(struct cec_adapter *adap, 145 struct cec_log_addrs __user *parg) 146 { 147 struct cec_log_addrs log_addrs; 148 149 mutex_lock(&adap->lock); 150 /* 151 * We use memcpy here instead of assignment since there is a 152 * hole at the end of struct cec_log_addrs that an assignment 153 * might ignore. So when we do copy_to_user() we could leak 154 * one byte of memory. 155 */ 156 memcpy(&log_addrs, &adap->log_addrs, sizeof(log_addrs)); 157 if (!adap->is_configured) 158 memset(log_addrs.log_addr, CEC_LOG_ADDR_INVALID, 159 sizeof(log_addrs.log_addr)); 160 mutex_unlock(&adap->lock); 161 162 if (copy_to_user(parg, &log_addrs, sizeof(log_addrs))) 163 return -EFAULT; 164 return 0; 165 } 166 167 static long cec_adap_s_log_addrs(struct cec_adapter *adap, struct cec_fh *fh, 168 bool block, struct cec_log_addrs __user *parg) 169 { 170 struct cec_log_addrs log_addrs; 171 long err = -EBUSY; 172 173 if (!(adap->capabilities & CEC_CAP_LOG_ADDRS)) 174 return -ENOTTY; 175 if (copy_from_user(&log_addrs, parg, sizeof(log_addrs))) 176 return -EFAULT; 177 log_addrs.flags &= CEC_LOG_ADDRS_FL_ALLOW_UNREG_FALLBACK | 178 CEC_LOG_ADDRS_FL_ALLOW_RC_PASSTHRU | 179 CEC_LOG_ADDRS_FL_CDC_ONLY; 180 mutex_lock(&adap->lock); 181 if (!adap->is_claiming_log_addrs && !adap->is_configuring && 182 (!log_addrs.num_log_addrs || !adap->is_configured) && 183 !cec_is_busy(adap, fh)) { 184 err = __cec_s_log_addrs(adap, &log_addrs, block); 185 if (!err) 186 log_addrs = adap->log_addrs; 187 } 188 mutex_unlock(&adap->lock); 189 if (err) 190 return err; 191 if (copy_to_user(parg, &log_addrs, sizeof(log_addrs))) 192 return -EFAULT; 193 return 0; 194 } 195 196 static long cec_adap_g_connector_info(struct cec_adapter *adap, 197 struct cec_log_addrs __user *parg) 198 { 199 int ret = 0; 200 201 if (!(adap->capabilities & CEC_CAP_CONNECTOR_INFO)) 202 return -ENOTTY; 203 204 mutex_lock(&adap->lock); 205 if (copy_to_user(parg, &adap->conn_info, sizeof(adap->conn_info))) 206 ret = -EFAULT; 207 mutex_unlock(&adap->lock); 208 return ret; 209 } 210 211 static long cec_transmit(struct cec_adapter *adap, struct cec_fh *fh, 212 bool block, struct cec_msg __user *parg) 213 { 214 struct cec_msg msg = {}; 215 long err = 0; 216 217 if (!(adap->capabilities & CEC_CAP_TRANSMIT)) 218 return -ENOTTY; 219 if (copy_from_user(&msg, parg, sizeof(msg))) 220 return -EFAULT; 221 222 mutex_lock(&adap->lock); 223 if (adap->log_addrs.num_log_addrs == 0) 224 err = -EPERM; 225 else if (adap->is_configuring) 226 err = -ENONET; 227 else if (cec_is_busy(adap, fh)) 228 err = -EBUSY; 229 else 230 err = cec_transmit_msg_fh(adap, &msg, fh, block); 231 mutex_unlock(&adap->lock); 232 if (err) 233 return err; 234 if (copy_to_user(parg, &msg, sizeof(msg))) 235 return -EFAULT; 236 return 0; 237 } 238 239 /* Called by CEC_RECEIVE: wait for a message to arrive */ 240 static int cec_receive_msg(struct cec_fh *fh, struct cec_msg *msg, bool block) 241 { 242 u32 timeout = msg->timeout; 243 int res; 244 245 do { 246 mutex_lock(&fh->lock); 247 /* Are there received messages queued up? */ 248 if (fh->queued_msgs) { 249 /* Yes, return the first one */ 250 struct cec_msg_entry *entry = 251 list_first_entry(&fh->msgs, 252 struct cec_msg_entry, list); 253 254 list_del(&entry->list); 255 *msg = entry->msg; 256 kfree(entry); 257 fh->queued_msgs--; 258 mutex_unlock(&fh->lock); 259 /* restore original timeout value */ 260 msg->timeout = timeout; 261 return 0; 262 } 263 264 /* No, return EAGAIN in non-blocking mode or wait */ 265 mutex_unlock(&fh->lock); 266 267 /* Return when in non-blocking mode */ 268 if (!block) 269 return -EAGAIN; 270 271 if (msg->timeout) { 272 /* The user specified a timeout */ 273 res = wait_event_interruptible_timeout(fh->wait, 274 fh->queued_msgs, 275 msecs_to_jiffies(msg->timeout)); 276 if (res == 0) 277 res = -ETIMEDOUT; 278 else if (res > 0) 279 res = 0; 280 } else { 281 /* Wait indefinitely */ 282 res = wait_event_interruptible(fh->wait, 283 fh->queued_msgs); 284 } 285 /* Exit on error, otherwise loop to get the new message */ 286 } while (!res); 287 return res; 288 } 289 290 static long cec_receive(struct cec_adapter *adap, struct cec_fh *fh, 291 bool block, struct cec_msg __user *parg) 292 { 293 struct cec_msg msg = {}; 294 long err; 295 296 if (copy_from_user(&msg, parg, sizeof(msg))) 297 return -EFAULT; 298 299 err = cec_receive_msg(fh, &msg, block); 300 if (err) 301 return err; 302 msg.flags = 0; 303 if (copy_to_user(parg, &msg, sizeof(msg))) 304 return -EFAULT; 305 return 0; 306 } 307 308 static long cec_dqevent(struct cec_adapter *adap, struct cec_fh *fh, 309 bool block, struct cec_event __user *parg) 310 { 311 struct cec_event_entry *ev = NULL; 312 u64 ts = ~0ULL; 313 unsigned int i; 314 unsigned int ev_idx; 315 long err = 0; 316 317 mutex_lock(&fh->lock); 318 while (!fh->total_queued_events && block) { 319 mutex_unlock(&fh->lock); 320 err = wait_event_interruptible(fh->wait, 321 fh->total_queued_events); 322 if (err) 323 return err; 324 mutex_lock(&fh->lock); 325 } 326 327 /* Find the oldest event */ 328 for (i = 0; i < CEC_NUM_EVENTS; i++) { 329 struct cec_event_entry *entry = 330 list_first_entry_or_null(&fh->events[i], 331 struct cec_event_entry, list); 332 333 if (entry && entry->ev.ts <= ts) { 334 ev = entry; 335 ev_idx = i; 336 ts = ev->ev.ts; 337 } 338 } 339 340 if (!ev) { 341 err = -EAGAIN; 342 goto unlock; 343 } 344 list_del(&ev->list); 345 346 if (copy_to_user(parg, &ev->ev, sizeof(ev->ev))) 347 err = -EFAULT; 348 if (ev_idx >= CEC_NUM_CORE_EVENTS) 349 kfree(ev); 350 fh->queued_events[ev_idx]--; 351 fh->total_queued_events--; 352 353 unlock: 354 mutex_unlock(&fh->lock); 355 return err; 356 } 357 358 static long cec_g_mode(struct cec_adapter *adap, struct cec_fh *fh, 359 u32 __user *parg) 360 { 361 u32 mode = fh->mode_initiator | fh->mode_follower; 362 363 if (copy_to_user(parg, &mode, sizeof(mode))) 364 return -EFAULT; 365 return 0; 366 } 367 368 static long cec_s_mode(struct cec_adapter *adap, struct cec_fh *fh, 369 u32 __user *parg) 370 { 371 u32 mode; 372 u8 mode_initiator; 373 u8 mode_follower; 374 bool send_pin_event = false; 375 long err = 0; 376 377 if (copy_from_user(&mode, parg, sizeof(mode))) 378 return -EFAULT; 379 if (mode & ~(CEC_MODE_INITIATOR_MSK | CEC_MODE_FOLLOWER_MSK)) { 380 dprintk(1, "%s: invalid mode bits set\n", __func__); 381 return -EINVAL; 382 } 383 384 mode_initiator = mode & CEC_MODE_INITIATOR_MSK; 385 mode_follower = mode & CEC_MODE_FOLLOWER_MSK; 386 387 if (mode_initiator > CEC_MODE_EXCL_INITIATOR || 388 mode_follower > CEC_MODE_MONITOR_ALL) { 389 dprintk(1, "%s: unknown mode\n", __func__); 390 return -EINVAL; 391 } 392 393 if (mode_follower == CEC_MODE_MONITOR_ALL && 394 !(adap->capabilities & CEC_CAP_MONITOR_ALL)) { 395 dprintk(1, "%s: MONITOR_ALL not supported\n", __func__); 396 return -EINVAL; 397 } 398 399 if (mode_follower == CEC_MODE_MONITOR_PIN && 400 !(adap->capabilities & CEC_CAP_MONITOR_PIN)) { 401 dprintk(1, "%s: MONITOR_PIN not supported\n", __func__); 402 return -EINVAL; 403 } 404 405 /* Follower modes should always be able to send CEC messages */ 406 if ((mode_initiator == CEC_MODE_NO_INITIATOR || 407 !(adap->capabilities & CEC_CAP_TRANSMIT)) && 408 mode_follower >= CEC_MODE_FOLLOWER && 409 mode_follower <= CEC_MODE_EXCL_FOLLOWER_PASSTHRU) { 410 dprintk(1, "%s: cannot transmit\n", __func__); 411 return -EINVAL; 412 } 413 414 /* Monitor modes require CEC_MODE_NO_INITIATOR */ 415 if (mode_initiator && mode_follower >= CEC_MODE_MONITOR_PIN) { 416 dprintk(1, "%s: monitor modes require NO_INITIATOR\n", 417 __func__); 418 return -EINVAL; 419 } 420 421 /* Monitor modes require CAP_NET_ADMIN */ 422 if (mode_follower >= CEC_MODE_MONITOR_PIN && !capable(CAP_NET_ADMIN)) 423 return -EPERM; 424 425 mutex_lock(&adap->lock); 426 /* 427 * You can't become exclusive follower if someone else already 428 * has that job. 429 */ 430 if ((mode_follower == CEC_MODE_EXCL_FOLLOWER || 431 mode_follower == CEC_MODE_EXCL_FOLLOWER_PASSTHRU) && 432 adap->cec_follower && adap->cec_follower != fh) 433 err = -EBUSY; 434 /* 435 * You can't become exclusive initiator if someone else already 436 * has that job. 437 */ 438 if (mode_initiator == CEC_MODE_EXCL_INITIATOR && 439 adap->cec_initiator && adap->cec_initiator != fh) 440 err = -EBUSY; 441 442 if (!err) { 443 bool old_mon_all = fh->mode_follower == CEC_MODE_MONITOR_ALL; 444 bool new_mon_all = mode_follower == CEC_MODE_MONITOR_ALL; 445 446 if (old_mon_all != new_mon_all) { 447 if (new_mon_all) 448 err = cec_monitor_all_cnt_inc(adap); 449 else 450 cec_monitor_all_cnt_dec(adap); 451 } 452 } 453 454 if (!err) { 455 bool old_mon_pin = fh->mode_follower == CEC_MODE_MONITOR_PIN; 456 bool new_mon_pin = mode_follower == CEC_MODE_MONITOR_PIN; 457 458 if (old_mon_pin != new_mon_pin) { 459 send_pin_event = new_mon_pin; 460 if (new_mon_pin) 461 err = cec_monitor_pin_cnt_inc(adap); 462 else 463 cec_monitor_pin_cnt_dec(adap); 464 } 465 } 466 467 if (err) { 468 mutex_unlock(&adap->lock); 469 return err; 470 } 471 472 if (fh->mode_follower == CEC_MODE_FOLLOWER) 473 adap->follower_cnt--; 474 if (mode_follower == CEC_MODE_FOLLOWER) 475 adap->follower_cnt++; 476 if (send_pin_event) { 477 struct cec_event ev = { 478 .flags = CEC_EVENT_FL_INITIAL_STATE, 479 }; 480 481 ev.event = adap->cec_pin_is_high ? CEC_EVENT_PIN_CEC_HIGH : 482 CEC_EVENT_PIN_CEC_LOW; 483 cec_queue_event_fh(fh, &ev, 0); 484 } 485 if (mode_follower == CEC_MODE_EXCL_FOLLOWER || 486 mode_follower == CEC_MODE_EXCL_FOLLOWER_PASSTHRU) { 487 adap->passthrough = 488 mode_follower == CEC_MODE_EXCL_FOLLOWER_PASSTHRU; 489 adap->cec_follower = fh; 490 } else if (adap->cec_follower == fh) { 491 adap->passthrough = false; 492 adap->cec_follower = NULL; 493 } 494 if (mode_initiator == CEC_MODE_EXCL_INITIATOR) 495 adap->cec_initiator = fh; 496 else if (adap->cec_initiator == fh) 497 adap->cec_initiator = NULL; 498 fh->mode_initiator = mode_initiator; 499 fh->mode_follower = mode_follower; 500 mutex_unlock(&adap->lock); 501 return 0; 502 } 503 504 static long cec_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 505 { 506 struct cec_fh *fh = filp->private_data; 507 struct cec_adapter *adap = fh->adap; 508 bool block = !(filp->f_flags & O_NONBLOCK); 509 void __user *parg = (void __user *)arg; 510 511 if (!cec_is_registered(adap)) 512 return -ENODEV; 513 514 switch (cmd) { 515 case CEC_ADAP_G_CAPS: 516 return cec_adap_g_caps(adap, parg); 517 518 case CEC_ADAP_G_PHYS_ADDR: 519 return cec_adap_g_phys_addr(adap, parg); 520 521 case CEC_ADAP_S_PHYS_ADDR: 522 return cec_adap_s_phys_addr(adap, fh, block, parg); 523 524 case CEC_ADAP_G_LOG_ADDRS: 525 return cec_adap_g_log_addrs(adap, parg); 526 527 case CEC_ADAP_S_LOG_ADDRS: 528 return cec_adap_s_log_addrs(adap, fh, block, parg); 529 530 case CEC_ADAP_G_CONNECTOR_INFO: 531 return cec_adap_g_connector_info(adap, parg); 532 533 case CEC_TRANSMIT: 534 return cec_transmit(adap, fh, block, parg); 535 536 case CEC_RECEIVE: 537 return cec_receive(adap, fh, block, parg); 538 539 case CEC_DQEVENT: 540 return cec_dqevent(adap, fh, block, parg); 541 542 case CEC_G_MODE: 543 return cec_g_mode(adap, fh, parg); 544 545 case CEC_S_MODE: 546 return cec_s_mode(adap, fh, parg); 547 548 default: 549 return -ENOTTY; 550 } 551 } 552 553 static int cec_open(struct inode *inode, struct file *filp) 554 { 555 struct cec_devnode *devnode = 556 container_of(inode->i_cdev, struct cec_devnode, cdev); 557 struct cec_adapter *adap = to_cec_adapter(devnode); 558 struct cec_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL); 559 /* 560 * Initial events that are automatically sent when the cec device is 561 * opened. 562 */ 563 struct cec_event ev = { 564 .event = CEC_EVENT_STATE_CHANGE, 565 .flags = CEC_EVENT_FL_INITIAL_STATE, 566 }; 567 unsigned int i; 568 int err; 569 570 if (!fh) 571 return -ENOMEM; 572 573 INIT_LIST_HEAD(&fh->msgs); 574 INIT_LIST_HEAD(&fh->xfer_list); 575 for (i = 0; i < CEC_NUM_EVENTS; i++) 576 INIT_LIST_HEAD(&fh->events[i]); 577 mutex_init(&fh->lock); 578 init_waitqueue_head(&fh->wait); 579 580 fh->mode_initiator = CEC_MODE_INITIATOR; 581 fh->adap = adap; 582 583 err = cec_get_device(devnode); 584 if (err) { 585 kfree(fh); 586 return err; 587 } 588 589 filp->private_data = fh; 590 591 /* Queue up initial state events */ 592 ev.state_change.phys_addr = adap->phys_addr; 593 ev.state_change.log_addr_mask = adap->log_addrs.log_addr_mask; 594 ev.state_change.have_conn_info = 595 adap->conn_info.type != CEC_CONNECTOR_TYPE_NO_CONNECTOR; 596 cec_queue_event_fh(fh, &ev, 0); 597 #ifdef CONFIG_CEC_PIN 598 if (adap->pin && adap->pin->ops->read_hpd && 599 !adap->devnode.unregistered) { 600 err = adap->pin->ops->read_hpd(adap); 601 if (err >= 0) { 602 ev.event = err ? CEC_EVENT_PIN_HPD_HIGH : 603 CEC_EVENT_PIN_HPD_LOW; 604 cec_queue_event_fh(fh, &ev, 0); 605 } 606 } 607 if (adap->pin && adap->pin->ops->read_5v && 608 !adap->devnode.unregistered) { 609 err = adap->pin->ops->read_5v(adap); 610 if (err >= 0) { 611 ev.event = err ? CEC_EVENT_PIN_5V_HIGH : 612 CEC_EVENT_PIN_5V_LOW; 613 cec_queue_event_fh(fh, &ev, 0); 614 } 615 } 616 #endif 617 618 mutex_lock(&devnode->lock); 619 mutex_lock(&devnode->lock_fhs); 620 list_add(&fh->list, &devnode->fhs); 621 mutex_unlock(&devnode->lock_fhs); 622 mutex_unlock(&devnode->lock); 623 624 return 0; 625 } 626 627 /* Override for the release function */ 628 static int cec_release(struct inode *inode, struct file *filp) 629 { 630 struct cec_devnode *devnode = cec_devnode_data(filp); 631 struct cec_adapter *adap = to_cec_adapter(devnode); 632 struct cec_fh *fh = filp->private_data; 633 unsigned int i; 634 635 mutex_lock(&adap->lock); 636 if (adap->cec_initiator == fh) 637 adap->cec_initiator = NULL; 638 if (adap->cec_follower == fh) { 639 adap->cec_follower = NULL; 640 adap->passthrough = false; 641 } 642 if (fh->mode_follower == CEC_MODE_FOLLOWER) 643 adap->follower_cnt--; 644 if (fh->mode_follower == CEC_MODE_MONITOR_PIN) 645 cec_monitor_pin_cnt_dec(adap); 646 if (fh->mode_follower == CEC_MODE_MONITOR_ALL) 647 cec_monitor_all_cnt_dec(adap); 648 mutex_unlock(&adap->lock); 649 650 mutex_lock(&devnode->lock); 651 mutex_lock(&devnode->lock_fhs); 652 list_del(&fh->list); 653 mutex_unlock(&devnode->lock_fhs); 654 mutex_unlock(&devnode->lock); 655 656 /* Unhook pending transmits from this filehandle. */ 657 mutex_lock(&adap->lock); 658 while (!list_empty(&fh->xfer_list)) { 659 struct cec_data *data = 660 list_first_entry(&fh->xfer_list, struct cec_data, xfer_list); 661 662 data->blocking = false; 663 data->fh = NULL; 664 list_del_init(&data->xfer_list); 665 } 666 mutex_unlock(&adap->lock); 667 668 mutex_lock(&fh->lock); 669 while (!list_empty(&fh->msgs)) { 670 struct cec_msg_entry *entry = 671 list_first_entry(&fh->msgs, struct cec_msg_entry, list); 672 673 list_del(&entry->list); 674 kfree(entry); 675 } 676 for (i = CEC_NUM_CORE_EVENTS; i < CEC_NUM_EVENTS; i++) { 677 while (!list_empty(&fh->events[i])) { 678 struct cec_event_entry *entry = 679 list_first_entry(&fh->events[i], 680 struct cec_event_entry, list); 681 682 list_del(&entry->list); 683 kfree(entry); 684 } 685 } 686 mutex_unlock(&fh->lock); 687 kfree(fh); 688 689 cec_put_device(devnode); 690 filp->private_data = NULL; 691 return 0; 692 } 693 694 const struct file_operations cec_devnode_fops = { 695 .owner = THIS_MODULE, 696 .open = cec_open, 697 .unlocked_ioctl = cec_ioctl, 698 .compat_ioctl = cec_ioctl, 699 .release = cec_release, 700 .poll = cec_poll, 701 .llseek = no_llseek, 702 }; 703