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
25static 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
34static __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, wait_address: &fh->wait, p: 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(lock: &adap->lock);
53 return res;
54}
55
56static 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
75static 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(to: parg, from: &caps, n: sizeof(caps)))
87 return -EFAULT;
88 return 0;
89}
90
91static 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(lock: &adap->lock);
99 if (copy_to_user(to: parg, from: &phys_addr, n: sizeof(phys_addr)))
100 return -EFAULT;
101 return 0;
102}
103
104static 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
121static 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(to: &phys_addr, from: parg, n: 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(lock: &adap->lock);
141 return err;
142}
143
144static 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(lock: &adap->lock);
161
162 if (copy_to_user(to: parg, from: &log_addrs, n: sizeof(log_addrs)))
163 return -EFAULT;
164 return 0;
165}
166
167static 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(to: &log_addrs, from: parg, n: 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_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: &log_addrs, block);
185 if (!err)
186 log_addrs = adap->log_addrs;
187 }
188 mutex_unlock(lock: &adap->lock);
189 if (err)
190 return err;
191 if (copy_to_user(to: parg, from: &log_addrs, n: sizeof(log_addrs)))
192 return -EFAULT;
193 return 0;
194}
195
196static 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(to: parg, from: &adap->conn_info, n: sizeof(adap->conn_info)))
206 ret = -EFAULT;
207 mutex_unlock(lock: &adap->lock);
208 return ret;
209}
210
211static 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(to: &msg, from: parg, n: 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: &msg, fh, block);
231 mutex_unlock(lock: &adap->lock);
232 if (err)
233 return err;
234 if (copy_to_user(to: parg, from: &msg, n: sizeof(msg)))
235 return -EFAULT;
236 return 0;
237}
238
239/* Called by CEC_RECEIVE: wait for a message to arrive */
240static 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: &entry->list);
255 *msg = entry->msg;
256 kfree(objp: entry);
257 fh->queued_msgs--;
258 mutex_unlock(lock: &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(lock: &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
290static 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(to: &msg, from: parg, n: sizeof(msg)))
297 return -EFAULT;
298
299 err = cec_receive_msg(fh, msg: &msg, block);
300 if (err)
301 return err;
302 msg.flags = 0;
303 if (copy_to_user(to: parg, from: &msg, n: sizeof(msg)))
304 return -EFAULT;
305 return 0;
306}
307
308static 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(lock: &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(entry: &ev->list);
345
346 if (copy_to_user(to: parg, from: &ev->ev, n: sizeof(ev->ev)))
347 err = -EFAULT;
348 if (ev_idx >= CEC_NUM_CORE_EVENTS)
349 kfree(objp: ev);
350 fh->queued_events[ev_idx]--;
351 fh->total_queued_events--;
352
353unlock:
354 mutex_unlock(lock: &fh->lock);
355 return err;
356}
357
358static 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(to: parg, from: &mode, n: sizeof(mode)))
364 return -EFAULT;
365 return 0;
366}
367
368static 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(to: &mode, from: parg, n: 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(lock: &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, new_ev: &ev, ts: 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(lock: &adap->lock);
501 return 0;
502}
503
504static 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
553static 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(size: 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(list: &fh->msgs);
574 INIT_LIST_HEAD(list: &fh->xfer_list);
575 for (i = 0; i < CEC_NUM_EVENTS; i++)
576 INIT_LIST_HEAD(list: &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(objp: 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, new_ev: &ev, ts: 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, new_ev: &ev, ts: 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, new_ev: &ev, ts: 0);
614 }
615 }
616#endif
617
618 mutex_lock(&devnode->lock);
619 mutex_lock(&devnode->lock_fhs);
620 list_add(new: &fh->list, head: &devnode->fhs);
621 mutex_unlock(lock: &devnode->lock_fhs);
622 mutex_unlock(lock: &devnode->lock);
623
624 return 0;
625}
626
627/* Override for the release function */
628static 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(lock: &adap->lock);
649
650 mutex_lock(&devnode->lock);
651 mutex_lock(&devnode->lock_fhs);
652 list_del(entry: &fh->list);
653 mutex_unlock(lock: &devnode->lock_fhs);
654 mutex_unlock(lock: &devnode->lock);
655
656 /* Unhook pending transmits from this filehandle. */
657 mutex_lock(&adap->lock);
658 while (!list_empty(head: &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(entry: &data->xfer_list);
665 }
666 mutex_unlock(lock: &adap->lock);
667 while (!list_empty(head: &fh->msgs)) {
668 struct cec_msg_entry *entry =
669 list_first_entry(&fh->msgs, struct cec_msg_entry, list);
670
671 list_del(entry: &entry->list);
672 kfree(objp: entry);
673 }
674 for (i = CEC_NUM_CORE_EVENTS; i < CEC_NUM_EVENTS; i++) {
675 while (!list_empty(head: &fh->events[i])) {
676 struct cec_event_entry *entry =
677 list_first_entry(&fh->events[i],
678 struct cec_event_entry, list);
679
680 list_del(entry: &entry->list);
681 kfree(objp: entry);
682 }
683 }
684 kfree(objp: fh);
685
686 cec_put_device(devnode);
687 filp->private_data = NULL;
688 return 0;
689}
690
691const struct file_operations cec_devnode_fops = {
692 .owner = THIS_MODULE,
693 .open = cec_open,
694 .unlocked_ioctl = cec_ioctl,
695 .compat_ioctl = cec_ioctl,
696 .release = cec_release,
697 .poll = cec_poll,
698 .llseek = no_llseek,
699};
700

source code of linux/drivers/media/cec/core/cec-api.c