text: // SPDX-License-Identifier: GPL-2.0-only
  /*
   * cec-adap.c - HDMI Consumer Electronics Control framework - CEC adapter
   *
   * Copyright 2016 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
   */
  
  #include <linux/errno.h>
  #include <linux/init.h>
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/kmod.h>
  #include <linux/ktime.h>
  #include <linux/slab.h>
  #include <linux/mm.h>
  #include <linux/string.h>
  #include <linux/types.h>
  
  #include <drm/drm_connector.h>
  #include <drm/drm_device.h>
  #include <drm/drm_edid.h>
  #include <drm/drm_file.h>
  
  #include "cec-priv.h"
  
  static void cec_fill_msg_report_features(struct cec_adapter *adap,
  					 struct cec_msg *msg,
  					 unsigned int la_idx);
  
  /*
   * 400 ms is the time it takes for one 16 byte message to be
   * transferred and 5 is the maximum number of retries. Add
   * another 100 ms as a margin. So if the transmit doesn't
   * finish before that time something is really wrong and we
   * have to time out.
   *
   * This is a sign that something it really wrong and a warning
   * will be issued.
   */
  #define CEC_XFER_TIMEOUT_MS (5 * 400 + 100)
  
  #define call_op(adap, op, arg...) \
  	(adap->ops->op ? adap->ops->op(adap, ## arg) : 0)
  
  #define call_void_op(adap, op, arg...)			\
  	do {						\
  		if (adap->ops->op)			\
  			adap->ops->op(adap, ## arg);	\
  	} while (0)
  
  static int cec_log_addr2idx(const struct cec_adapter *adap, u8 log_addr)
  {
  	int i;
  
  	for (i = 0; i < adap->log_addrs.num_log_addrs; i++)
  		if (adap->log_addrs.log_addr[i] == log_addr)
  			return i;
  	return -1;
  }
  
  static unsigned int cec_log_addr2dev(const struct cec_adapter *adap, u8 log_addr)
  {
  	int i = cec_log_addr2idx(adap, log_addr);
  
  	return adap->log_addrs.primary_device_type[i < 0 ? 0 : i];
  }
  
  u16 cec_get_edid_phys_addr(const u8 *edid, unsigned int size,
  			   unsigned int *offset)
  {
  	unsigned int loc = cec_get_edid_spa_location(edid, size);
  
  	if (offset)
  		*offset = loc;
  	if (loc == 0)
  		return CEC_PHYS_ADDR_INVALID;
  	return (edid[loc] << 8) | edid[loc + 1];
  }
  EXPORT_SYMBOL_GPL(cec_get_edid_phys_addr);
  
  void cec_fill_conn_info_from_drm(struct cec_connector_info *conn_info,
  				 const struct drm_connector *connector)
  {
  	memset(conn_info, 0, sizeof(*conn_info));
  	conn_info->type = CEC_CONNECTOR_TYPE_DRM;
  	conn_info->drm.card_no = connector->dev->primary->index;
  	conn_info->drm.connector_id = connector->base.id;
  }
  EXPORT_SYMBOL_GPL(cec_fill_conn_info_from_drm);
  
  /*
   * Queue a new event for this filehandle. If ts == 0, then set it
   * to the current time.
   *
   * We keep a queue of at most max_event events where max_event differs
   * per event. If the queue becomes full, then drop the oldest event and
   * keep track of how many events we've dropped.
   */
  void cec_queue_event_fh(struct cec_fh *fh,
  			const struct cec_event *new_ev, u64 ts)
  {
  	static const u16 max_events[CEC_NUM_EVENTS] = {
  		1, 1, 800, 800, 8, 8, 8, 8
  	};
  	struct cec_event_entry *entry;
  	unsigned int ev_idx = new_ev->event - 1;
  
  	if (WARN_ON(ev_idx >= ARRAY_SIZE(fh->events)))
  		return;
  
  	if (ts == 0)
  		ts = ktime_get_ns();
  
  	mutex_lock(&fh->lock);
  	if (ev_idx < CEC_NUM_CORE_EVENTS)
  		entry = &fh->core_events[ev_idx];
  	else
  		entry = kmalloc(sizeof(*entry), GFP_KERNEL);
  	if (entry) {
  		if (new_ev->event == CEC_EVENT_LOST_MSGS &&
  		    fh->queued_events[ev_idx]) {
  			entry->ev.lost_msgs.lost_msgs +=
  				new_ev->lost_msgs.lost_msgs;
  			goto unlock;
  		}
  		entry->ev = *new_ev;
  		entry->ev.ts = ts;
  
  		if (fh->queued_events[ev_idx] < max_events[ev_idx]) {
  			/* Add new msg at the end of the queue */
  			list_add_tail(&entry->list, &fh->events[ev_idx]);
  			fh->queued_events[ev_idx]++;
  			fh->total_queued_events++;
  			goto unlock;
  		}
  
  		if (ev_idx >= CEC_NUM_CORE_EVENTS) {
  			list_add_tail(&entry->list, &fh->events[ev_idx]);
  			/* drop the oldest event */
  			entry = list_first_entry(&fh->events[ev_idx],
  						 struct cec_event_entry, list);
  			list_del(&entry->list);
  			kfree(entry);
  		}
  	}
  	/* Mark that events were lost */
  	entry = list_first_entry_or_null(&fh->events[ev_idx],
  					 struct cec_event_entry, list);
  	if (entry)
  		entry->ev.flags |= CEC_EVENT_FL_DROPPED_EVENTS;
  
  unlock:
  	mutex_unlock(&fh->lock);
  	wake_up_interruptible(&fh->wait);
  }
  
  /* Queue a new event for all open filehandles. */
  static void cec_queue_event(struct cec_adapter *adap,
  			    const struct cec_event *ev)
  {
  	u64 ts = ktime_get_ns();
  	struct cec_fh *fh;
  
  	mutex_lock(&adap->devnode.lock);
  	list_for_each_entry(fh, &adap->devnode.fhs, list)
  		cec_queue_event_fh(fh, ev, ts);
  	mutex_unlock(&adap->devnode.lock);
  }
  
  /* Notify userspace that the CEC pin changed state at the given time. */
  void cec_queue_pin_cec_event(struct cec_adapter *adap, bool is_high,
  			     bool dropped_events, ktime_t ts)
  {
  	struct cec_event ev = {
  		.event = is_high ? CEC_EVENT_PIN_CEC_HIGH :
  				   CEC_EVENT_PIN_CEC_LOW,
  		.flags = dropped_events ? CEC_EVENT_FL_DROPPED_EVENTS : 0,
  	};
  	struct cec_fh *fh;
  
  	mutex_lock(&adap->devnode.lock);
  	list_for_each_entry(fh, &adap->devnode.fhs, list)
  		if (fh->mode_follower == CEC_MODE_MONITOR_PIN)
  			cec_queue_event_fh(fh, &ev, ktime_to_ns(ts));
  	mutex_unlock(&adap->devnode.lock);
  }
  EXPORT_SYMBOL_GPL(cec_queue_pin_cec_event);
  
  /* Notify userspace that the HPD pin changed state at the given time. */
  void cec_queue_pin_hpd_event(struct cec_adapter *adap, bool is_high, ktime_t ts)
  {
  	struct cec_event ev = {
  		.event = is_high ? CEC_EVENT_PIN_HPD_HIGH :
  				   CEC_EVENT_PIN_HPD_LOW,
  	};
  	struct cec_fh *fh;
  
  	mutex_lock(&adap->devnode.lock);
  	list_for_each_entry(fh, &adap->devnode.fhs, list)
  		cec_queue_event_fh(fh, &ev, ktime_to_ns(ts));
  	mutex_unlock(&adap->devnode.lock);
  }
  EXPORT_SYMBOL_GPL(cec_queue_pin_hpd_event);
  
  /* Notify userspace that the 5V pin changed state at the given time. */
  void cec_queue_pin_5v_event(struct cec_adapter *adap, bool is_high, ktime_t ts)
  {
  	struct cec_event ev = {
  		.event = is_high ? CEC_EVENT_PIN_5V_HIGH :
  				   CEC_EVENT_PIN_5V_LOW,
  	};
  	struct cec_fh *fh;
  
  	mutex_lock(&adap->devnode.lock);
  	list_for_each_entry(fh, &adap->devnode.fhs, list)
  		cec_queue_event_fh(fh, &ev, ktime_to_ns(ts));
  	mutex_unlock(&adap->devnode.lock);
  }
  EXPORT_SYMBOL_GPL(cec_queue_pin_5v_event);
  
  /*
   * Queue a new message for this filehandle.
   *
   * We keep a queue of at most CEC_MAX_MSG_RX_QUEUE_SZ messages. If the
   * queue becomes full, then drop the oldest message and keep track
   * of how many messages we've dropped.
   */
  static void cec_queue_msg_fh(struct cec_fh *fh, const struct cec_msg *msg)
  {
  	static const struct cec_event ev_lost_msgs = {
  		.event = CEC_EVENT_LOST_MSGS,
  		.flags = 0,
  		{
  			.lost_msgs = { 1 },
  		},
  	};
  	struct cec_msg_entry *entry;
  
  	mutex_lock(&fh->lock);
  	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
  	if (entry) {
  		entry->msg = *msg;
  		/* Add new msg at the end of the queue */
  		list_add_tail(&entry->list, &fh->msgs);
  
  		if (fh->queued_msgs < CEC_MAX_MSG_RX_QUEUE_SZ) {
  			/* All is fine if there is enough room */
  			fh->queued_msgs++;
  			mutex_unlock(&fh->lock);
  			wake_up_interruptible(&fh->wait);
  			return;
  		}
  
  		/*
  		 * if the message queue is full, then drop the oldest one and
  		 * send a lost message event.
  		 */
  		entry = list_first_entry(&fh->msgs, struct cec_msg_entry, list);
  		list_del(&entry->list);
  		kfree(entry);
  	}
  	mutex_unlock(&fh->lock);
  
  	/*
  	 * We lost a message, either because kmalloc failed or the queue
  	 * was full.
  	 */
  	cec_queue_event_fh(fh, &ev_lost_msgs, ktime_get_ns());
  }
  
  /*
   * Queue the message for those filehandles that are in monitor mode.
   * If valid_la is true (this message is for us or was sent by us),
   * then pass it on to any monitoring filehandle. If this message
   * isn't for us or from us, then only give it to filehandles that
   * are in MONITOR_ALL mode.
   *
   * This can only happen if the CEC_CAP_MONITOR_ALL capability is
   * set and the CEC adapter was placed in 'monitor all' mode.
   */
  static void cec_queue_msg_monitor(struct cec_adapter *adap,
  				  const struct cec_msg *msg,
  				  bool valid_la)
  {
  	struct cec_fh *fh;
  	u32 monitor_mode = valid_la ? CEC_MODE_MONITOR :
  				      CEC_MODE_MONITOR_ALL;
  
  	mutex_lock(&adap->devnode.lock);
  	list_for_each_entry(fh, &adap->devnode.fhs, list) {
  		if (fh->mode_follower >= monitor_mode)
  			cec_queue_msg_fh(fh, msg);
  	}
  	mutex_unlock(&adap->devnode.lock);
  }
  
  /*
   * Queue the message for follower filehandles.
   */
  static void cec_queue_msg_followers(struct cec_adapter *adap,
  				    const struct cec_msg *msg)
  {
  	struct cec_fh *fh;
  
  	mutex_lock(&adap->devnode.lock);
  	list_for_each_entry(fh, &adap->devnode.fhs, list) {
  		if (fh->mode_follower == CEC_MODE_FOLLOWER)
  			cec_queue_msg_fh(fh, msg);
  	}
  	mutex_unlock(&adap->devnode.lock);
  }
  
  /* Notify userspace of an adapter state change. */
  static void cec_post_state_event(struct cec_adapter *adap)
  {
  	struct cec_event ev = {
  		.event = CEC_EVENT_STATE_CHANGE,
  	};
  
  	ev.state_change.phys_addr = adap->phys_addr;
  	ev.state_change.log_addr_mask = adap->log_addrs.log_addr_mask;
  	ev.state_change.have_conn_info =
  		adap->conn_info.type != CEC_CONNECTOR_TYPE_NO_CONNECTOR;
  	cec_queue_event(adap, &ev);
  }
  
  /*
   * A CEC transmit (and a possible wait for reply) completed.
   * If this was in blocking mode, then complete it, otherwise
   * queue the message for userspace to dequeue later.
   *
   * This function is called with adap->lock held.
   */
  static void cec_data_completed(struct cec_data *data)
  {
  	/*
  	 * Delete this transmit from the filehandle's xfer_list since
  	 * we're done with it.
  	 *
  	 * Note that if the filehandle is closed before this transmit
  	 * finished, then the release() function will set data->fh to NULL.
  	 * Without that we would be referring to a closed filehandle.
  	 */
  	if (data->fh)
  		list_del(&data->xfer_list);
  
  	if (data->blocking) {
  		/*
  		 * Someone is blocking so mark the message as completed
  		 * and call complete.
  		 */
  		data->completed = true;
  		complete(&data->c);
  	} else {
  		/*
  		 * No blocking, so just queue the message if needed and
  		 * free the memory.
  		 */
  		if (data->fh)
  			cec_queue_msg_fh(data->fh, &data->msg);
  		kfree(data);
  	}
  }
  
  /*
   * A pending CEC transmit needs to be cancelled, either because the CEC
   * adapter is disabled or the transmit takes an impossibly long time to
   * finish.
   *
   * This function is called with adap->lock held.
   */
  static void cec_data_cancel(struct cec_data *data, u8 tx_status)
  {
  	/*
  	 * It's either the current transmit, or it is a pending
  	 * transmit. Take the appropriate action to clear it.
  	 */
  	if (data->adap->transmitting == data) {
  		data->adap->transmitting = NULL;
  	} else {
  		list_del_init(&data->list);
  		if (!(data->msg.tx_status & CEC_TX_STATUS_OK))
  			if (!WARN_ON(!data->adap->transmit_queue_sz))
  				data->adap->transmit_queue_sz--;
  	}
  
  	if (data->msg.tx_status & CEC_TX_STATUS_OK) {
  		data->msg.rx_ts = ktime_get_ns();
  		data->msg.rx_status = CEC_RX_STATUS_ABORTED;
  	} else {
  		data->msg.tx_ts = ktime_get_ns();
  		data->msg.tx_status |= tx_status |
  				       CEC_TX_STATUS_MAX_RETRIES;
  		data->msg.tx_error_cnt++;
  		data->attempts = 0;
  	}
  
  	/* Queue transmitted message for monitoring purposes */
  	cec_queue_msg_monitor(data->adap, &data->msg, 1);
  
  	cec_data_completed(data);
  }
  
  /*
   * Flush all pending transmits and cancel any pending timeout work.
   *
   * This function is called with adap->lock held.
   */
  static void cec_flush(struct cec_adapter *adap)
  {
  	struct cec_data *data, *n;
  
  	/*
  	 * If the adapter is disabled, or we're asked to stop,
  	 * then cancel any pending transmits.
  	 */
  	while (!list_empty(&adap->transmit_queue)) {
  		data = list_first_entry(&adap->transmit_queue,
  					struct cec_data, list);
  		cec_data_cancel(data, CEC_TX_STATUS_ABORTED);
  	}
  	if (adap->transmitting)
  		cec_data_cancel(adap->transmitting, CEC_TX_STATUS_ABORTED);
  
  	/* Cancel the pending timeout work. */
  	list_for_each_entry_safe(data, n, &adap->wait_queue, list) {
  		if (cancel_delayed_work(&data->work))
  			cec_data_cancel(data, CEC_TX_STATUS_OK);
  		/*
  		 * If cancel_delayed_work returned false, then
  		 * the cec_wait_timeout function is running,
  		 * which will call cec_data_completed. So no
  		 * need to do anything special in that case.
  		 */
  	}
  	/*
  	 * If something went wrong and this counter isn't what it should
  	 * be, then this will reset it back to 0. Warn if it is not 0,
  	 * since it indicates a bug, either in this framework or in a
  	 * CEC driver.
  	 */
  	if (WARN_ON(adap->transmit_queue_sz))
  		adap->transmit_queue_sz = 0;
  }
  
  /*
   * Main CEC state machine
   *
   * Wait until the thread should be stopped, or we are not transmitting and
   * a new transmit message is queued up, in which case we start transmitting
   * that message. When the adapter finished transmitting the message it will
   * call cec_transmit_done().
   *
   * If the adapter is disabled, then remove all queued messages instead.
   *
   * If the current transmit times out, then cancel that transmit.
   */
  int cec_thread_func(void *_adap)
  {
  	struct cec_adapter *adap = _adap;
  
  	for (;;) {
  		unsigned int signal_free_time;
  		struct cec_data *data;
  		bool timeout = false;
  		u8 attempts;
  
  		if (adap->transmit_in_progress) {
  			int err;
  
  			/*
  			 * We are transmitting a message, so add a timeout
  			 * to prevent the state machine to get stuck waiting
  			 * for this message to finalize and add a check to
  			 * see if the adapter is disabled in which case the
  			 * transmit should be canceled.
  			 */
  			err = wait_event_interruptible_timeout(adap->kthread_waitq,
  				(adap->needs_hpd &&
  				 (!adap->is_configured && !adap->is_configuring)) ||
  				kthread_should_stop() ||
  				(!adap->transmit_in_progress &&
  				 !list_empty(&adap->transmit_queue)),
  				msecs_to_jiffies(CEC_XFER_TIMEOUT_MS));
  			timeout = err == 0;
  		} else {
  			/* Otherwise we just wait for something to happen. */
  			wait_event_interruptible(adap->kthread_waitq,
  				kthread_should_stop() ||
  				(!adap->transmit_in_progress &&
  				 !list_empty(&adap->transmit_queue)));
  		}
  
  		mutex_lock(&adap->lock);
  
  		if ((adap->needs_hpd &&
  		     (!adap->is_configured && !adap->is_configuring)) ||
  		    kthread_should_stop()) {
  			cec_flush(adap);
  			goto unlock;
  		}
  
  		if (adap->transmit_in_progress && timeout) {
  			/*
  			 * If we timeout, then log that. Normally this does
  			 * not happen and it is an indication of a faulty CEC
  			 * adapter driver, or the CEC bus is in some weird
  			 * state. On rare occasions it can happen if there is
  			 * so much traffic on the bus that the adapter was
  			 * unable to transmit for CEC_XFER_TIMEOUT_MS (2.1s).
  			 */
  			if (adap->transmitting) {
  				pr_warn("cec-%s: message %*ph timed out\n", adap->name,
  					adap->transmitting->msg.len,
  					adap->transmitting->msg.msg);
  				/* Just give up on this. */
  				cec_data_cancel(adap->transmitting,
  						CEC_TX_STATUS_TIMEOUT);
  			} else {
  				pr_warn("cec-%s: transmit timed out\n", adap->name);
  			}
  			adap->transmit_in_progress = false;
  			adap->tx_timeouts++;
  			goto unlock;
  		}
  
  		/*
  		 * If we are still transmitting, or there is nothing new to
  		 * transmit, then just continue waiting.
  		 */
  		if (adap->transmit_in_progress || list_empty(&adap->transmit_queue))
  			goto unlock;
  
  		/* Get a new message to transmit */
  		data = list_first_entry(&adap->transmit_queue,
  					struct cec_data, list);
  		list_del_init(&data->list);
  		if (!WARN_ON(!data->adap->transmit_queue_sz))
  			adap->transmit_queue_sz--;
  
  		/* Make this the current transmitting message */
  		adap->transmitting = data;
  
  		/*
  		 * Suggested number of attempts as per the CEC 2.0 spec:
  		 * 4 attempts is the default, except for 'secondary poll
  		 * messages', i.e. poll messages not sent during the adapter
  		 * configuration phase when it allocates logical addresses.
  		 */
  		if (data->msg.len == 1 && adap->is_configured)
  			attempts = 2;
  		else
  			attempts = 4;
  
  		/* Set the suggested signal free time */
  		if (data->attempts) {
  			/* should be >= 3 data bit periods for a retry */
  			signal_free_time = CEC_SIGNAL_FREE_TIME_RETRY;
  		} else if (adap->last_initiator !=
  			   cec_msg_initiator(&data->msg)) {
  			/* should be >= 5 data bit periods for new initiator */
  			signal_free_time = CEC_SIGNAL_FREE_TIME_NEW_INITIATOR;
  			adap->last_initiator = cec_msg_initiator(&data->msg);
  		} else {
  			/*
  			 * should be >= 7 data bit periods for sending another
  			 * frame immediately after another.
  			 */
  			signal_free_time = CEC_SIGNAL_FREE_TIME_NEXT_XFER;
  		}
  		if (data->attempts == 0)
  			data->attempts = attempts;
  
  		/* Tell the adapter to transmit, cancel on error */
  		if (adap->ops->adap_transmit(adap, data->attempts,
  					     signal_free_time, &data->msg))
  			cec_data_cancel(data, CEC_TX_STATUS_ABORTED);
  		else
  			adap->transmit_in_progress = true;
  
  unlock:
  		mutex_unlock(&adap->lock);
  
  		if (kthread_should_stop())
  			break;
  	}
  	return 0;
  }
  
  /*
   * Called by the CEC adapter if a transmit finished.
   */
  void cec_transmit_done_ts(struct cec_adapter *adap, u8 status,
  			  u8 arb_lost_cnt, u8 nack_cnt, u8 low_drive_cnt,
  			  u8 error_cnt, ktime_t ts)
  {
  	struct cec_data *data;
  	struct cec_msg *msg;
  	unsigned int attempts_made = arb_lost_cnt + nack_cnt +
  				     low_drive_cnt + error_cnt;
  
  	dprintk(2, "%s: status 0x%02x\n", __func__, status);
  	if (attempts_made < 1)
  		attempts_made = 1;
  
  	mutex_lock(&adap->lock);
  	data = adap->transmitting;
  	if (!data) {
  		/*
  		 * This might happen if a transmit was issued and the cable is
  		 * unplugged while the transmit is ongoing. Ignore this
  		 * transmit in that case.
  		 */
  		if (!adap->transmit_in_progress)
  			dprintk(1, "%s was called without an ongoing transmit!\n",
  				__func__);
  		adap->transmit_in_progress = false;
  		goto wake_thread;
  	}
  	adap->transmit_in_progress = false;
  
  	msg = &data->msg;
  
  	/* Drivers must fill in the status! */
  	WARN_ON(status == 0);
  	msg->tx_ts = ktime_to_ns(ts);
  	msg->tx_status |= status;
  	msg->tx_arb_lost_cnt += arb_lost_cnt;
  	msg->tx_nack_cnt += nack_cnt;
  	msg->tx_low_drive_cnt += low_drive_cnt;
  	msg->tx_error_cnt += error_cnt;
  
  	/* Mark that we're done with this transmit */
  	adap->transmitting = NULL;
  
  	/*
  	 * If there are still retry attempts left and there was an error and
  	 * the hardware didn't signal that it retried itself (by setting
  	 * CEC_TX_STATUS_MAX_RETRIES), then we will retry ourselves.
  	 */
  	if (data->attempts > attempts_made &&
  	    !(status & (CEC_TX_STATUS_MAX_RETRIES | CEC_TX_STATUS_OK))) {
  		/* Retry this message */
  		data->attempts -= attempts_made;
  		if (msg->timeout)
  			dprintk(2, "retransmit: %*ph (attempts: %d, wait for 0x%02x)\n",
  				msg->len, msg->msg, data->attempts, msg->reply);
  		else
  			dprintk(2, "retransmit: %*ph (attempts: %d)\n",
  				msg->len, msg->msg, data->attempts);
  		/* Add the message in front of the transmit queue */
  		list_add(&data->list, &adap->transmit_queue);
  		adap->transmit_queue_sz++;
  		goto wake_thread;
  	}
  
  	data->attempts = 0;
  
  	/* Always set CEC_TX_STATUS_MAX_RETRIES on error */
  	if (!(status & CEC_TX_STATUS_OK))
  		msg->tx_status |= CEC_TX_STATUS_MAX_RETRIES;
  
  	/* Queue transmitted message for monitoring purposes */
  	cec_queue_msg_monitor(adap, msg, 1);
  
  	if ((status & CEC_TX_STATUS_OK) && adap->is_configured &&
  	    msg->timeout) {
  		/*
  		 * Queue the message into the wait queue if we want to wait
  		 * for a reply.
  		 */
  		list_add_tail(&data->list, &adap->wait_queue);
  		schedule_delayed_work(&data->work,
  				      msecs_to_jiffies(msg->timeout));
  	} else {
  		/* Otherwise we're done */
  		cec_data_completed(data);
  	}
  
  wake_thread:
  	/*
  	 * Wake up the main thread to see if another message is ready
  	 * for transmitting or to retry the current message.
  	 */
  	wake_up_interruptible(&adap->kthread_waitq);
  	mutex_unlock(&adap->lock);
  }
  EXPORT_SYMBOL_GPL(cec_transmit_done_ts);
  
  void cec_transmit_attempt_done_ts(struct cec_adapter *adap,
  				  u8 status, ktime_t ts)
  {
  	switch (status & ~CEC_TX_STATUS_MAX_RETRIES) {
  	case CEC_TX_STATUS_OK:
  		cec_transmit_done_ts(adap, status, 0, 0, 0, 0, ts);
  		return;
  	case CEC_TX_STATUS_ARB_LOST:
  		cec_transmit_done_ts(adap, status, 1, 0, 0, 0, ts);
  		return;
  	case CEC_TX_STATUS_NACK:
  		cec_transmit_done_ts(adap, status, 0, 1, 0, 0, ts);
  		return;
  	case CEC_TX_STATUS_LOW_DRIVE:
  		cec_transmit_done_ts(adap, status, 0, 0, 1, 0, ts);
  		return;
  	case CEC_TX_STATUS_ERROR:
  		cec_transmit_done_ts(adap, status, 0, 0, 0, 1, ts);
  		return;
  	default:
  		/* Should never happen */
  		WARN(1, "cec-%s: invalid status 0x%02x\n", adap->name, status);
  		return;
  	}
  }
  EXPORT_SYMBOL_GPL(cec_transmit_attempt_done_ts);
  
  /*
   * Called when waiting for a reply times out.
   */
  static void cec_wait_timeout(struct work_struct *work)
  {
  	struct cec_data *data = container_of(work, struct cec_data, work.work);
  	struct cec_adapter *adap = data->adap;
  
  	mutex_lock(&adap->lock);
  	/*
  	 * Sanity check in case the timeout and the arrival of the message
  	 * happened at the same time.
  	 */
  	if (list_empty(&data->list))
  		goto unlock;
  
  	/* Mark the message as timed out */
  	list_del_init(&data->list);
  	data->msg.rx_ts = ktime_get_ns();
  	data->msg.rx_status = CEC_RX_STATUS_TIMEOUT;
  	cec_data_completed(data);
  unlock:
  	mutex_unlock(&adap->lock);
  }
  
  /*
   * Transmit a message. The fh argument may be NULL if the transmit is not
   * associated with a specific filehandle.
   *
   * This function is called with adap->lock held.
   */
  int cec_transmit_msg_fh(struct cec_adapter *adap, struct cec_msg *msg,
  			struct cec_fh *fh, bool block)
  {
  	struct cec_data *data;
  	bool is_raw = msg_is_raw(msg);
  
  	if (adap->devnode.unregistered)
  		return -ENODEV;
  
  	msg->rx_ts = 0;
  	msg->tx_ts = 0;
  	msg->rx_status = 0;
  	msg->tx_status = 0;
  	msg->tx_arb_lost_cnt = 0;
  	msg->tx_nack_cnt = 0;
  	msg->tx_low_drive_cnt = 0;
  	msg->tx_error_cnt = 0;
  	msg->sequence = 0;
  
  	if (msg->reply && msg->timeout == 0) {
  		/* Make sure the timeout isn't 0. */
  		msg->timeout = 1000;
  	}
  	msg->flags &= CEC_MSG_FL_REPLY_TO_FOLLOWERS | CEC_MSG_FL_RAW;
  
  	if (!msg->timeout)
  		msg->flags &= ~CEC_MSG_FL_REPLY_TO_FOLLOWERS;
  
  	/* Sanity checks */
  	if (msg->len == 0 || msg->len > CEC_MAX_MSG_SIZE) {
  		dprintk(1, "%s: invalid length %d\n", __func__, msg->len);
  		return -EINVAL;
  	}
  
  	memset(msg->msg + msg->len, 0, sizeof(msg->msg) - msg->len);
  
  	if (msg->timeout)
  		dprintk(2, "%s: %*ph (wait for 0x%02x%s)\n",
  			__func__, msg->len, msg->msg, msg->reply,
  			!block ? ", nb" : "");
  	else
  		dprintk(2, "%s: %*ph%s\n",
  			__func__, msg->len, msg->msg, !block ? " (nb)" : "");
  
  	if (msg->timeout && msg->len == 1) {
  		dprintk(1, "%s: can't reply to poll msg\n", __func__);
  		return -EINVAL;
  	}
  
  	if (is_raw) {
  		if (!capable(CAP_SYS_RAWIO))
  			return -EPERM;
  	} else {
  		/* A CDC-Only device can only send CDC messages */
  		if ((adap->log_addrs.flags & CEC_LOG_ADDRS_FL_CDC_ONLY) &&
  		    (msg->len == 1 || msg->msg[1] != CEC_MSG_CDC_MESSAGE)) {
  			dprintk(1, "%s: not a CDC message\n", __func__);
  			return -EINVAL;
  		}
  
  		if (msg->len >= 4 && msg->msg[1] == CEC_MSG_CDC_MESSAGE) {
  			msg->msg[2] = adap->phys_addr >> 8;
  			msg->msg[3] = adap->phys_addr & 0xff;
  		}
  
  		if (msg->len == 1) {
  			if (cec_msg_destination(msg) == 0xf) {
  				dprintk(1, "%s: invalid poll message\n",
  					__func__);
  				return -EINVAL;
  			}
  			if (cec_has_log_addr(adap, cec_msg_destination(msg))) {
  				/*
  				 * If the destination is a logical address our
  				 * adapter has already claimed, then just NACK
  				 * this. It depends on the hardware what it will
  				 * do with a POLL to itself (some OK this), so
  				 * it is just as easy to handle it here so the
  				 * behavior will be consistent.
  				 */
  				msg->tx_ts = ktime_get_ns();
  				msg->tx_status = CEC_TX_STATUS_NACK |
  					CEC_TX_STATUS_MAX_RETRIES;
  				msg->tx_nack_cnt = 1;
  				msg->sequence = ++adap->sequence;
  				if (!msg->sequence)
  					msg->sequence = ++adap->sequence;
  				return 0;
  			}
  		}
  		if (msg->len > 1 && !cec_msg_is_broadcast(msg) &&
  		    cec_has_log_addr(adap, cec_msg_destination(msg))) {
  			dprintk(1, "%s: destination is the adapter itself\n",
  				__func__);
  			return -EINVAL;
  		}
  		if (msg->len > 1 && adap->is_configured &&
  		    !cec_has_log_addr(adap, cec_msg_initiator(msg))) {
  			dprintk(1, "%s: initiator has unknown logical address %d\n",
  				__func__, cec_msg_initiator(msg));
  			return -EINVAL;
  		}
  		/*
  		 * Special case: allow Ping and IMAGE/TEXT_VIEW_ON to be
  		 * transmitted to a TV, even if the adapter is unconfigured.
  		 * This makes it possible to detect or wake up displays that
  		 * pull down the HPD when in standby.
  		 */
  		if (!adap->is_configured && !adap->is_configuring &&
  		    (msg->len > 2 ||
  		     cec_msg_destination(msg) != CEC_LOG_ADDR_TV ||
  		     (msg->len == 2 && msg->msg[1] != CEC_MSG_IMAGE_VIEW_ON &&
  		      msg->msg[1] != CEC_MSG_TEXT_VIEW_ON))) {
  			dprintk(1, "%s: adapter is unconfigured\n", __func__);
  			return -ENONET;
  		}
  	}
  
  	if (!adap->is_configured && !adap->is_configuring) {
  		if (adap->needs_hpd) {
  			dprintk(1, "%s: adapter is unconfigured and needs HPD\n",
  				__func__);
  			return -ENONET;
  		}
  		if (msg->reply) {
  			dprintk(1, "%s: invalid msg->reply\n", __func__);
  			return -EINVAL;
  		}
  	}
  
  	if (adap->transmit_queue_sz >= CEC_MAX_MSG_TX_QUEUE_SZ) {
  		dprintk(2, "%s: transmit queue full\n", __func__);
  		return -EBUSY;
  	}
  
  	data = kzalloc(sizeof(*data), GFP_KERNEL);
  	if (!data)
  		return -ENOMEM;
  
  	msg->sequence = ++adap->sequence;
  	if (!msg->sequence)
  		msg->sequence = ++adap->sequence;
  
  	data->msg = *msg;
  	data->fh = fh;
  	data->adap = adap;
  	data->blocking = block;
  
  	init_completion(&data->c);
  	INIT_DELAYED_WORK(&data->work, cec_wait_timeout);
  
  	if (fh)
  		list_add_tail(&data->xfer_list, &fh->xfer_list);
  
  	list_add_tail(&data->list, &adap->transmit_queue);
  	adap->transmit_queue_sz++;
  	if (!adap->transmitting)
  		wake_up_interruptible(&adap->kthread_waitq);
  
  	/* All done if we don't need to block waiting for completion */
  	if (!block)
  		return 0;
  
  	/*
  	 * Release the lock and wait, retake the lock afterwards.
  	 */
  	mutex_unlock(&adap->lock);
  	wait_for_completion_killable(&data->c);
  	if (!data->completed)
  		cancel_delayed_work_sync(&data->work);
  	mutex_lock(&adap->lock);
  
  	/* Cancel the transmit if it was interrupted */
  	if (!data->completed)
  		cec_data_cancel(data, CEC_TX_STATUS_ABORTED);
  
  	/* The transmit completed (possibly with an error) */
  	*msg = data->msg;
  	kfree(data);
  	return 0;
  }
  
  /* Helper function to be used by drivers and this framework. */
  int cec_transmit_msg(struct cec_adapter *adap, struct cec_msg *msg,
  		     bool block)
  {
  	int ret;
  
  	mutex_lock(&adap->lock);
  	ret = cec_transmit_msg_fh(adap, msg, NULL, block);
  	mutex_unlock(&adap->lock);
  	return ret;
  }
  EXPORT_SYMBOL_GPL(cec_transmit_msg);
  
  /*
   * I don't like forward references but without this the low-level
   * cec_received_msg() function would come after a bunch of high-level
   * CEC protocol handling functions. That was very confusing.
   */
  static int cec_receive_notify(struct cec_adapter *adap, struct cec_msg *msg,
  			      bool is_reply);
  
  #define DIRECTED	0x80
  #define BCAST1_4	0x40
  #define BCAST2_0	0x20	/* broadcast only allowed for >= 2.0 */
  #define BCAST		(BCAST1_4 | BCAST2_0)
  #define BOTH		(BCAST | DIRECTED)
  
  /*
   * Specify minimum length and whether the message is directed, broadcast
   * or both. Messages that do not match the criteria are ignored as per
   * the CEC specification.
   */
  static const u8 cec_msg_size[256] = {
  	[CEC_MSG_ACTIVE_SOURCE] = 4 | BCAST,
  	[CEC_MSG_IMAGE_VIEW_ON] = 2 | DIRECTED,
  	[CEC_MSG_TEXT_VIEW_ON] = 2 | DIRECTED,
  	[CEC_MSG_INACTIVE_SOURCE] = 4 | DIRECTED,
  	[CEC_MSG_REQUEST_ACTIVE_SOURCE] = 2 | BCAST,
  	[CEC_MSG_ROUTING_CHANGE] = 6 | BCAST,
  	[CEC_MSG_ROUTING_INFORMATION] = 4 | BCAST,
  	[CEC_MSG_SET_STREAM_PATH] = 4 | BCAST,
  	[CEC_MSG_STANDBY] = 2 | BOTH,
  	[CEC_MSG_RECORD_OFF] = 2 | DIRECTED,
  	[CEC_MSG_RECORD_ON] = 3 | DIRECTED,
  	[CEC_MSG_RECORD_STATUS] = 3 | DIRECTED,
  	[CEC_MSG_RECORD_TV_SCREEN] = 2 | DIRECTED,
  	[CEC_MSG_CLEAR_ANALOGUE_TIMER] = 13 | DIRECTED,
  	[CEC_MSG_CLEAR_DIGITAL_TIMER] = 16 | DIRECTED,
  	[CEC_MSG_CLEAR_EXT_TIMER] = 13 | DIRECTED,
  	[CEC_MSG_SET_ANALOGUE_TIMER] = 13 | DIRECTED,
  	[CEC_MSG_SET_DIGITAL_TIMER] = 16 | DIRECTED,
  	[CEC_MSG_SET_EXT_TIMER] = 13 | DIRECTED,
  	[CEC_MSG_SET_TIMER_PROGRAM_TITLE] = 2 | DIRECTED,
  	[CEC_MSG_TIMER_CLEARED_STATUS] = 3 | DIRECTED,
  	[CEC_MSG_TIMER_STATUS] = 3 | DIRECTED,
  	[CEC_MSG_CEC_VERSION] = 3 | DIRECTED,
  	[CEC_MSG_GET_CEC_VERSION] = 2 | DIRECTED,
  	[CEC_MSG_GIVE_PHYSICAL_ADDR] = 2 | DIRECTED,
  	[CEC_MSG_GET_MENU_LANGUAGE] = 2 | DIRECTED,
  	[CEC_MSG_REPORT_PHYSICAL_ADDR] = 5 | BCAST,
  	[CEC_MSG_SET_MENU_LANGUAGE] = 5 | BCAST,
  	[CEC_MSG_REPORT_FEATURES] = 6 | BCAST,
  	[CEC_MSG_GIVE_FEATURES] = 2 | DIRECTED,
  	[CEC_MSG_DECK_CONTROL] = 3 | DIRECTED,
  	[CEC_MSG_DECK_STATUS] = 3 | DIRECTED,
  	[CEC_MSG_GIVE_DECK_STATUS] = 3 | DIRECTED,
  	[CEC_MSG_PLAY] = 3 | DIRECTED,
  	[CEC_MSG_GIVE_TUNER_DEVICE_STATUS] = 3 | DIRECTED,
  	[CEC_MSG_SELECT_ANALOGUE_SERVICE] = 6 | DIRECTED,
  	[CEC_MSG_SELECT_DIGITAL_SERVICE] = 9 | DIRECTED,
  	[CEC_MSG_TUNER_DEVICE_STATUS] = 7 | DIRECTED,
  	[CEC_MSG_TUNER_STEP_DECREMENT] = 2 | DIRECTED,
  	[CEC_MSG_TUNER_STEP_INCREMENT] = 2 | DIRECTED,
  	[CEC_MSG_DEVICE_VENDOR_ID] = 5 | BCAST,
  	[CEC_MSG_GIVE_DEVICE_VENDOR_ID] = 2 | DIRECTED,
  	[CEC_MSG_VENDOR_COMMAND] = 2 | DIRECTED,
  	[CEC_MSG_VENDOR_COMMAND_WITH_ID] = 5 | BOTH,
  	[CEC_MSG_VENDOR_REMOTE_BUTTON_DOWN] = 2 | BOTH,
  	[CEC_MSG_VENDOR_REMOTE_BUTTON_UP] = 2 | BOTH,
  	[CEC_MSG_SET_OSD_STRING] = 3 | DIRECTED,
  	[CEC_MSG_GIVE_OSD_NAME] = 2 | DIRECTED,
  	[CEC_MSG_SET_OSD_NAME] = 2 | DIRECTED,
  	[CEC_MSG_MENU_REQUEST] = 3 | DIRECTED,
  	[CEC_MSG_MENU_STATUS] = 3 | DIRECTED,
  	[CEC_MSG_USER_CONTROL_PRESSED] = 3 | DIRECTED,
  	[CEC_MSG_USER_CONTROL_RELEASED] = 2 | DIRECTED,
  	[CEC_MSG_GIVE_DEVICE_POWER_STATUS] = 2 | DIRECTED,
  	[CEC_MSG_REPORT_POWER_STATUS] = 3 | DIRECTED | BCAST2_0,
  	[CEC_MSG_FEATURE_ABORT] = 4 | DIRECTED,
  	[CEC_MSG_ABORT] = 2 | DIRECTED,
  	[CEC_MSG_GIVE_AUDIO_STATUS] = 2 | DIRECTED,
  	[CEC_MSG_GIVE_SYSTEM_AUDIO_MODE_STATUS] = 2 | DIRECTED,
  	[CEC_MSG_REPORT_AUDIO_STATUS] = 3 | DIRECTED,
  	[CEC_MSG_REPORT_SHORT_AUDIO_DESCRIPTOR] = 2 | DIRECTED,
  	[CEC_MSG_REQUEST_SHORT_AUDIO_DESCRIPTOR] = 2 | DIRECTED,
  	[CEC_MSG_SET_SYSTEM_AUDIO_MODE] = 3 | BOTH,
  	[CEC_MSG_SYSTEM_AUDIO_MODE_REQUEST] = 2 | DIRECTED,
  	[CEC_MSG_SYSTEM_AUDIO_MODE_STATUS] = 3 | DIRECTED,
  	[CEC_MSG_SET_AUDIO_RATE] = 3 | DIRECTED,
  	[CEC_MSG_INITIATE_ARC] = 2 | DIRECTED,
  	[CEC_MSG_REPORT_ARC_INITIATED] = 2 | DIRECTED,
  	[CEC_MSG_REPORT_ARC_TERMINATED] = 2 | DIRECTED,
  	[CEC_MSG_REQUEST_ARC_INITIATION] = 2 | DIRECTED,
  	[CEC_MSG_REQUEST_ARC_TERMINATION] = 2 | DIRECTED,
  	[CEC_MSG_TERMINATE_ARC] = 2 | DIRECTED,
  	[CEC_MSG_REQUEST_CURRENT_LATENCY] = 4 | BCAST,
  	[CEC_MSG_REPORT_CURRENT_LATENCY] = 6 | BCAST,
  	[CEC_MSG_CDC_MESSAGE] = 2 | BCAST,
  };
  
  /* Called by the CEC adapter if a message is received */
  void cec_received_msg_ts(struct cec_adapter *adap,
  			 struct cec_msg *msg, ktime_t ts)
  {
  	struct cec_data *data;
  	u8 msg_init = cec_msg_initiator(msg);
  	u8 msg_dest = cec_msg_destination(msg);
  	u8 cmd = msg->msg[1];
  	bool is_reply = false;
  	bool valid_la = true;
  	u8 min_len = 0;
  
  	if (WARN_ON(!msg->len || msg->len > CEC_MAX_MSG_SIZE))
  		return;
  
  	if (adap->devnode.unregistered)
  		return;
  
  	/*
  	 * Some CEC adapters will receive the messages that they transmitted.
  	 * This test filters out those messages by checking if we are the
  	 * initiator, and just returning in that case.
  	 *
  	 * Note that this won't work if this is an Unregistered device.
  	 *
  	 * It is bad practice if the hardware receives the message that it
  	 * transmitted and luckily most CEC adapters behave correctly in this
  	 * respect.
  	 */
  	if (msg_init != CEC_LOG_ADDR_UNREGISTERED &&
  	    cec_has_log_addr(adap, msg_init))
  		return;
  
  	msg->rx_ts = ktime_to_ns(ts);
  	msg->rx_status = CEC_RX_STATUS_OK;
  	msg->sequence = msg->reply = msg->timeout = 0;
  	msg->tx_status = 0;
  	msg->tx_ts = 0;
  	msg->tx_arb_lost_cnt = 0;
  	msg->tx_nack_cnt = 0;
  	msg->tx_low_drive_cnt = 0;
  	msg->tx_error_cnt = 0;
  	msg->flags = 0;
  	memset(msg->msg + msg->len, 0, sizeof(msg->msg) - msg->len);
  
  	mutex_lock(&adap->lock);
  	dprintk(2, "%s: %*ph\n", __func__, msg->len, msg->msg);
  
  	adap->last_initiator = 0xff;
  
  	/* Check if this message was for us (directed or broadcast). */
  	if (!cec_msg_is_broadcast(msg))
  		valid_la = cec_has_log_addr(adap, msg_dest);
  
  	/*
  	 * Check if the length is not too short or if the message is a
  	 * broadcast message where a directed message was expected or
  	 * vice versa. If so, then the message has to be ignored (according
  	 * to section CEC 7.3 and CEC 12.2).
  	 */
  	if (valid_la && msg->len > 1 && cec_msg_size[cmd]) {
  		u8 dir_fl = cec_msg_size[cmd] & BOTH;
  
  		min_len = cec_msg_size[cmd] & 0x1f;
  		if (msg->len < min_len)
  			valid_la = false;
  		else if (!cec_msg_is_broadcast(msg) && !(dir_fl & DIRECTED))
  			valid_la = false;
  		else if (cec_msg_is_broadcast(msg) && !(dir_fl & BCAST))
  			valid_la = false;
  		else if (cec_msg_is_broadcast(msg) &&
  			 adap->log_addrs.cec_version < CEC_OP_CEC_VERSION_2_0 &&
  			 !(dir_fl & BCAST1_4))
  			valid_la = false;
  	}
  	if (valid_la && min_len) {
  		/* These messages have special length requirements */
  		switch (cmd) {
  		case CEC_MSG_TIMER_STATUS:
  			if (msg->msg[2] & 0x10) {
  				switch (msg->msg[2] & 0xf) {
  				case CEC_OP_PROG_INFO_NOT_ENOUGH_SPACE:
  				case CEC_OP_PROG_INFO_MIGHT_NOT_BE_ENOUGH_SPACE:
  					if (msg->len < 5)
  						valid_la = false;
  					break;
  				}
  			} else if ((msg->msg[2] & 0xf) == CEC_OP_PROG_ERROR_DUPLICATE) {
  				if (msg->len < 5)
  					valid_la = false;
  			}
  			break;
  		case CEC_MSG_RECORD_ON:
  			switch (msg->msg[2]) {
  			case CEC_OP_RECORD_SRC_OWN:
  				break;
  			case CEC_OP_RECORD_SRC_DIGITAL:
  				if (msg->len < 10)
  					valid_la = false;
  				break;
  			case CEC_OP_RECORD_SRC_ANALOG:
  				if (msg->len < 7)
  					valid_la = false;
  				break;
  			case CEC_OP_RECORD_SRC_EXT_PLUG:
  				if (msg->len < 4)
  					valid_la = false;
  				break;
  			case CEC_OP_RECORD_SRC_EXT_PHYS_ADDR:
  				if (msg->len < 5)
  					valid_la = false;
  				break;
  			}
  			break;
  		}
  	}
  
  	/* It's a valid message and not a poll or CDC message */
  	if (valid_la && msg->len > 1 && cmd != CEC_MSG_CDC_MESSAGE) {
  		bool abort = cmd == CEC_MSG_FEATURE_ABORT;
  
  		/* The aborted command is in msg[2] */
  		if (abort)
  			cmd = msg->msg[2];
  
  		/*
  		 * Walk over all transmitted messages that are waiting for a
  		 * reply.
  		 */
  		list_for_each_entry(data, &adap->wait_queue, list) {
  			struct cec_msg *dst = &data->msg;
  
  			/*
  			 * The *only* CEC message that has two possible replies
  			 * is CEC_MSG_INITIATE_ARC.
  			 * In this case allow either of the two replies.
  			 */
  			if (!abort && dst->msg[1] == CEC_MSG_INITIATE_ARC &&
  			    (cmd == CEC_MSG_REPORT_ARC_INITIATED ||
  			     cmd == CEC_MSG_REPORT_ARC_TERMINATED) &&
  			    (dst->reply == CEC_MSG_REPORT_ARC_INITIATED ||
  			     dst->reply == CEC_MSG_REPORT_ARC_TERMINATED))
  				dst->reply = cmd;
  
  			/* Does the command match? */
  			if ((abort && cmd != dst->msg[1]) ||
  			    (!abort && cmd != dst->reply))
  				continue;
  
  			/* Does the addressing match? */
  			if (msg_init != cec_msg_destination(dst) &&
  			    !cec_msg_is_broadcast(dst))
  				continue;
  
  			/* We got a reply */
  			memcpy(dst->msg, msg->msg, msg->len);
  			dst->len = msg->len;
  			dst->rx_ts = msg->rx_ts;
  			dst->rx_status = msg->rx_status;
  			if (abort)
  				dst->rx_status |= CEC_RX_STATUS_FEATURE_ABORT;
  			msg->flags = dst->flags;
  			msg->sequence = dst->sequence;
  			/* Remove it from the wait_queue */
  			list_del_init(&data->list);
  
  			/* Cancel the pending timeout work */
  			if (!cancel_delayed_work(&data->work)) {
  				mutex_unlock(&adap->lock);
  				cancel_delayed_work_sync(&data->work);
  				mutex_lock(&adap->lock);
  			}
  			/*
  			 * Mark this as a reply, provided someone is still
  			 * waiting for the answer.
  			 */
  			if (data->fh)
  				is_reply = true;
  			cec_data_completed(data);
  			break;
  		}
  	}
  	mutex_unlock(&adap->lock);
  
  	/* Pass the message on to any monitoring filehandles */
  	cec_queue_msg_monitor(adap, msg, valid_la);
  
  	/* We're done if it is not for us or a poll message */
  	if (!valid_la || msg->len <= 1)
  		return;
  
  	if (adap->log_addrs.log_addr_mask == 0)
  		return;
  
  	/*
  	 * Process the message on the protocol level. If is_reply is true,
  	 * then cec_receive_notify() won't pass on the reply to the listener(s)
  	 * since that was already done by cec_data_completed() above.
  	 */
  	cec_receive_notify(adap, msg, is_reply);
  }
  EXPORT_SYMBOL_GPL(cec_received_msg_ts);
  
  /* Logical Address Handling */
  
  /*
   * Attempt to claim a specific logical address.
   *
   * This function is called with adap->lock held.
   */
  static int cec_config_log_addr(struct cec_adapter *adap,
  			       unsigned int idx,
  			       unsigned int log_addr)
  {
  	struct cec_log_addrs *las = &adap->log_addrs;
  	struct cec_msg msg = { };
  	const unsigned int max_retries = 2;
  	unsigned int i;
  	int err;
  
  	if (cec_has_log_addr(adap, log_addr))
  		return 0;
  
  	/* Send poll message */
  	msg.len = 1;
  	msg.msg[0] = (log_addr << 4) | log_addr;
  
  	for (i = 0; i < max_retries; i++) {
  		err = cec_transmit_msg_fh(adap, &msg, NULL, true);
  
  		/*
  		 * While trying to poll the physical address was reset
  		 * and the adapter was unconfigured, so bail out.
  		 */
  		if (!adap->is_configuring)
  			return -EINTR;
  
  		if (err)
  			return err;
  
  		/*
  		 * The message was aborted due to a disconnect or
  		 * unconfigure, just bail out.
  		 */
  		if (msg.tx_status & CEC_TX_STATUS_ABORTED)
  			return -EINTR;
  		if (msg.tx_status & CEC_TX_STATUS_OK)
  			return 0;
  		if (msg.tx_status & CEC_TX_STATUS_NACK)
  			break;
  		/*
  		 * Retry up to max_retries times if the message was neither
  		 * OKed or NACKed. This can happen due to e.g. a Lost
  		 * Arbitration condition.
  		 */
  	}
  
  	/*
  	 * If we are unable to get an OK or a NACK after max_retries attempts
  	 * (and note that each attempt already consists of four polls), then
  	 * we assume that something is really weird and that it is not a
  	 * good idea to try and claim this logical address.
  	 */
  	if (i == max_retries)
  		return 0;
  
  	/*
  	 * Message not acknowledged, so this logical
  	 * address is free to use.
  	 */
  	err = adap->ops->adap_log_addr(adap, log_addr);
  	if (err)
  		return err;
  
  	las->log_addr[idx] = log_addr;
  	las->log_addr_mask |= 1 << log_addr;
  	return 1;
  }
  
  /*
   * Unconfigure the adapter: clear all logical addresses and send
   * the state changed event.
   *
   * This function is called with adap->lock held.
   */
  static void cec_adap_unconfigure(struct cec_adapter *adap)
  {
  	if (!adap->needs_hpd ||
  	    adap->phys_addr != CEC_PHYS_ADDR_INVALID)
  		WARN_ON(adap->ops->adap_log_addr(adap, CEC_LOG_ADDR_INVALID));
  	adap->log_addrs.log_addr_mask = 0;
  	adap->is_configuring = false;
  	adap->is_configured = false;
  	cec_flush(adap);
  	wake_up_interruptible(&adap->kthread_waitq);
  	cec_post_state_event(adap);
  }
  
  /*
   * Attempt to claim the required logical addresses.
   */
  static int cec_config_thread_func(void *arg)
  {
  	/* The various LAs for each type of device */
  	static const u8 tv_log_addrs[] = {
  		CEC_LOG_ADDR_TV, CEC_LOG_ADDR_SPECIFIC,
  		CEC_LOG_ADDR_INVALID
  	};
  	static const u8 record_log_addrs[] = {
  		CEC_LOG_ADDR_RECORD_1, CEC_LOG_ADDR_RECORD_2,
  		CEC_LOG_ADDR_RECORD_3,
  		CEC_LOG_ADDR_BACKUP_1, CEC_LOG_ADDR_BACKUP_2,
  		CEC_LOG_ADDR_INVALID
  	};
  	static const u8 tuner_log_addrs[] = {
  		CEC_LOG_ADDR_TUNER_1, CEC_LOG_ADDR_TUNER_2,
  		CEC_LOG_ADDR_TUNER_3, CEC_LOG_ADDR_TUNER_4,
  		CEC_LOG_ADDR_BACKUP_1, CEC_LOG_ADDR_BACKUP_2,
  		CEC_LOG_ADDR_INVALID
  	};
  	static const u8 playback_log_addrs[] = {
  		CEC_LOG_ADDR_PLAYBACK_1, CEC_LOG_ADDR_PLAYBACK_2,
  		CEC_LOG_ADDR_PLAYBACK_3,
  		CEC_LOG_ADDR_BACKUP_1, CEC_LOG_ADDR_BACKUP_2,
  		CEC_LOG_ADDR_INVALID
  	};
  	static const u8 audiosystem_log_addrs[] = {
  		CEC_LOG_ADDR_AUDIOSYSTEM,
  		CEC_LOG_ADDR_INVALID
  	};
  	static const u8 specific_use_log_addrs[] = {
  		CEC_LOG_ADDR_SPECIFIC,
  		CEC_LOG_ADDR_BACKUP_1, CEC_LOG_ADDR_BACKUP_2,
  		CEC_LOG_ADDR_INVALID
  	};
  	static const u8 *type2addrs[6] = {
  		[CEC_LOG_ADDR_TYPE_TV] = tv_log_addrs,
  		[CEC_LOG_ADDR_TYPE_RECORD] = record_log_addrs,
  		[CEC_LOG_ADDR_TYPE_TUNER] = tuner_log_addrs,
  		[CEC_LOG_ADDR_TYPE_PLAYBACK] = playback_log_addrs,
  		[CEC_LOG_ADDR_TYPE_AUDIOSYSTEM] = audiosystem_log_addrs,
  		[CEC_LOG_ADDR_TYPE_SPECIFIC] = specific_use_log_addrs,
  	};
  	static const u16 type2mask[] = {
  		[CEC_LOG_ADDR_TYPE_TV] = CEC_LOG_ADDR_MASK_TV,
  		[CEC_LOG_ADDR_TYPE_RECORD] = CEC_LOG_ADDR_MASK_RECORD,
  		[CEC_LOG_ADDR_TYPE_TUNER] = CEC_LOG_ADDR_MASK_TUNER,
  		[CEC_LOG_ADDR_TYPE_PLAYBACK] = CEC_LOG_ADDR_MASK_PLAYBACK,
  		[CEC_LOG_ADDR_TYPE_AUDIOSYSTEM] = CEC_LOG_ADDR_MASK_AUDIOSYSTEM,
  		[CEC_LOG_ADDR_TYPE_SPECIFIC] = CEC_LOG_ADDR_MASK_SPECIFIC,
  	};
  	struct cec_adapter *adap = arg;
  	struct cec_log_addrs *las = &adap->log_addrs;
  	int err;
  	int i, j;
  
  	mutex_lock(&adap->lock);
  	dprintk(1, "physical address: %x.%x.%x.%x, claim %d logical addresses\n",
  		cec_phys_addr_exp(adap->phys_addr), las->num_log_addrs);
  	las->log_addr_mask = 0;
  
  	if (las->log_addr_type[0] == CEC_LOG_ADDR_TYPE_UNREGISTERED)
  		goto configured;
  
  	for (i = 0; i < las->num_log_addrs; i++) {
  		unsigned int type = las->log_addr_type[i];
  		const u8 *la_list;
  		u8 last_la;
  
  		/*
  		 * The TV functionality can only map to physical address 0.
  		 * For any other address, try the Specific functionality
  		 * instead as per the spec.
  		 */
  		if (adap->phys_addr && type == CEC_LOG_ADDR_TYPE_TV)
  			type = CEC_LOG_ADDR_TYPE_SPECIFIC;
  
  		la_list = type2addrs[type];
  		last_la = las->log_addr[i];
  		las->log_addr[i] = CEC_LOG_ADDR_INVALID;
  		if (last_la == CEC_LOG_ADDR_INVALID ||
  		    last_la == CEC_LOG_ADDR_UNREGISTERED ||
  		    !((1 << last_la) & type2mask[type]))
  			last_la = la_list[0];
  
  		err = cec_config_log_addr(adap, i, last_la);
  		if (err > 0) /* Reused last LA */
  			continue;
  
  		if (err < 0)
  			goto unconfigure;
  
  		for (j = 0; la_list[j] != CEC_LOG_ADDR_INVALID; j++) {
  			/* Tried this one already, skip it */
  			if (la_list[j] == last_la)
  				continue;
  			/* The backup addresses are CEC 2.0 specific */
  			if ((la_list[j] == CEC_LOG_ADDR_BACKUP_1 ||
  			     la_list[j] == CEC_LOG_ADDR_BACKUP_2) &&
  			    las->cec_version < CEC_OP_CEC_VERSION_2_0)
  				continue;
  
  			err = cec_config_log_addr(adap, i, la_list[j]);
  			if (err == 0) /* LA is in use */
  				continue;
  			if (err < 0)
  				goto unconfigure;
  			/* Done, claimed an LA */
  			break;
  		}
  
  		if (la_list[j] == CEC_LOG_ADDR_INVALID)
  			dprintk(1, "could not claim LA %d\n", i);
  	}
  
  	if (adap->log_addrs.log_addr_mask == 0 &&
  	    !(las->flags & CEC_LOG_ADDRS_FL_ALLOW_UNREG_FALLBACK))
  		goto unconfigure;
  
  configured:
  	if (adap->log_addrs.log_addr_mask == 0) {
  		/* Fall back to unregistered */
  		las->log_addr[0] = CEC_LOG_ADDR_UNREGISTERED;
  		las->log_addr_mask = 1 << las->log_addr[0];
  		for (i = 1; i < las->num_log_addrs; i++)
  			las->log_addr[i] = CEC_LOG_ADDR_INVALID;
  	}
  	for (i = las->num_log_addrs; i < CEC_MAX_LOG_ADDRS; i++)
  		las->log_addr[i] = CEC_LOG_ADDR_INVALID;
  	adap->is_configured = true;
  	adap->is_configuring = false;
  	cec_post_state_event(adap);
  
  	/*
  	 * Now post the Report Features and Report Physical Address broadcast
  	 * messages. Note that these are non-blocking transmits, meaning that
  	 * they are just queued up and once adap->lock is unlocked the main
  	 * thread will kick in and start transmitting these.
  	 *
  	 * If after this function is done (but before one or more of these
  	 * messages are actually transmitted) the CEC adapter is unconfigured,
  	 * then any remaining messages will be dropped by the main thread.
  	 */
  	for (i = 0; i < las->num_log_addrs; i++) {
  		struct cec_msg msg = {};
  
  		if (las->log_addr[i] == CEC_LOG_ADDR_INVALID ||
  		    (las->flags & CEC_LOG_ADDRS_FL_CDC_ONLY))
  			continue;
  
  		msg.msg[0] = (las->log_addr[i] << 4) | 0x0f;
  
  		/* Report Features must come first according to CEC 2.0 */
  		if (las->log_addr[i] != CEC_LOG_ADDR_UNREGISTERED &&
  		    adap->log_addrs.cec_version >= CEC_OP_CEC_VERSION_2_0) {
  			cec_fill_msg_report_features(adap, &msg, i);
  			cec_transmit_msg_fh(adap, &msg, NULL, false);
  		}
  
  		/* Report Physical Address */
  		cec_msg_report_physical_addr(&msg, adap->phys_addr,
  					     las->primary_device_type[i]);
  		dprintk(1, "config: la %d pa %x.%x.%x.%x\n",
  			las->log_addr[i],
  			cec_phys_addr_exp(adap->phys_addr));
  		cec_transmit_msg_fh(adap, &msg, NULL, false);
  
  		/* Report Vendor ID */
  		if (adap->log_addrs.vendor_id != CEC_VENDOR_ID_NONE) {
  			cec_msg_device_vendor_id(&msg,
  						 adap->log_addrs.vendor_id);
  			cec_transmit_msg_fh(adap, &msg, NULL, false);
  		}
  	}
  	adap->kthread_config = NULL;
  	complete(&adap->config_completion);
  	mutex_unlock(&adap->lock);
  	return 0;
  
  unconfigure:
  	for (i = 0; i < las->num_log_addrs; i++)
  		las->log_addr[i] = CEC_LOG_ADDR_INVALID;
  	cec_adap_unconfigure(adap);
  	adap->kthread_config = NULL;
  	mutex_unlock(&adap->lock);
  	complete(&adap->config_completion);
  	return 0;
  }
  
  /*
   * Called from either __cec_s_phys_addr or __cec_s_log_addrs to claim the
   * logical addresses.
   *
   * This function is called with adap->lock held.
   */
  static void cec_claim_log_addrs(struct cec_adapter *adap, bool block)
  {
  	if (WARN_ON(adap->is_configuring || adap->is_configured))
  		return;
  
  	init_completion(&adap->config_completion);
  
  	/* Ready to kick off the thread */
  	adap->is_configuring = true;
  	adap->kthread_config = kthread_run(cec_config_thread_func, adap,
  					   "ceccfg-%s", adap->name);
  	if (IS_ERR(adap->kthread_config)) {
  		adap->kthread_config = NULL;
  	} else if (block) {
  		mutex_unlock(&adap->lock);
  		wait_for_completion(&adap->config_completion);
  		mutex_lock(&adap->lock);
  	}
  }
  
  /* Set a new physical address and send an event notifying userspace of this.
   *
   * This function is called with adap->lock held.
   */
  void __cec_s_phys_addr(struct cec_adapter *adap, u16 phys_addr, bool block)
  {
  	if (phys_addr == adap->phys_addr)
  		return;
  	if (phys_addr != CEC_PHYS_ADDR_INVALID && adap->devnode.unregistered)
  		return;
  
  	dprintk(1, "new physical address %x.%x.%x.%x\n",
  		cec_phys_addr_exp(phys_addr));
  	if (phys_addr == CEC_PHYS_ADDR_INVALID ||
  	    adap->phys_addr != CEC_PHYS_ADDR_INVALID) {
  		adap->phys_addr = CEC_PHYS_ADDR_INVALID;
  		cec_post_state_event(adap);
  		cec_adap_unconfigure(adap);
  		/* Disabling monitor all mode should always succeed */
  		if (adap->monitor_all_cnt)
  			WARN_ON(call_op(adap, adap_monitor_all_enable, false));
  		mutex_lock(&adap->devnode.lock);
  		if (adap->needs_hpd || list_empty(&adap->devnode.fhs)) {
  			WARN_ON(adap->ops->adap_enable(adap, false));
  			adap->transmit_in_progress = false;
  			wake_up_interruptible(&adap->kthread_waitq);
  		}
  		mutex_unlock(&adap->devnode.lock);
  		if (phys_addr == CEC_PHYS_ADDR_INVALID)
  			return;
  	}
  
  	mutex_lock(&adap->devnode.lock);
  	adap->last_initiator = 0xff;
  	adap->transmit_in_progress = false;
  
  	if ((adap->needs_hpd || list_empty(&adap->devnode.fhs)) &&
  	    adap->ops->adap_enable(adap, true)) {
  		mutex_unlock(&adap->devnode.lock);
  		return;
  	}
  
  	if (adap->monitor_all_cnt &&
  	    call_op(adap, adap_monitor_all_enable, true)) {
  		if (adap->needs_hpd || list_empty(&adap->devnode.fhs))
  			WARN_ON(adap->ops->adap_enable(adap, false));
  		mutex_unlock(&adap->devnode.lock);
  		return;
  	}
  	mutex_unlock(&adap->devnode.lock);
  
  	adap->phys_addr = phys_addr;
  	cec_post_state_event(adap);
  	if (adap->log_addrs.num_log_addrs)
  		cec_claim_log_addrs(adap, block);
  }
  
  void cec_s_phys_addr(struct cec_adapter *adap, u16 phys_addr, bool block)
  {
  	if (IS_ERR_OR_NULL(adap))
  		return;
  
  	mutex_lock(&adap->lock);
  	__cec_s_phys_addr(adap, phys_addr, block);
  	mutex_unlock(&adap->lock);
  }
  EXPORT_SYMBOL_GPL(cec_s_phys_addr);
  
  void cec_s_phys_addr_from_edid(struct cec_adapter *adap,
  			       const struct edid *edid)
  {
  	u16 pa = CEC_PHYS_ADDR_INVALID;
  
  	if (edid && edid->extensions)
  		pa = cec_get_edid_phys_addr((const u8 *)edid,
  				EDID_LENGTH * (edid->extensions + 1), NULL);
  	cec_s_phys_addr(adap, pa, false);
  }
  EXPORT_SYMBOL_GPL(cec_s_phys_addr_from_edid);
  
  void cec_s_conn_info(struct cec_adapter *adap,
  		     const struct cec_connector_info *conn_info)
  {
  	if (IS_ERR_OR_NULL(adap))
  		return;
  
  	if (!(adap->capabilities & CEC_CAP_CONNECTOR_INFO))
  		return;
  
  	mutex_lock(&adap->lock);
  	if (conn_info)
  		adap->conn_info = *conn_info;
  	else
  		memset(&adap->conn_info, 0, sizeof(adap->conn_info));
  	cec_post_state_event(adap);
  	mutex_unlock(&adap->lock);
  }
  EXPORT_SYMBOL_GPL(cec_s_conn_info);
  
  /*
   * Called from either the ioctl or a driver to set the logical addresses.
   *
   * This function is called with adap->lock held.
   */
  int __cec_s_log_addrs(struct cec_adapter *adap,
  		      struct cec_log_addrs *log_addrs, bool block)
  {
  	u16 type_mask = 0;
  	int i;
  
  	if (adap->devnode.unregistered)
  		return -ENODEV;
  
  	if (!log_addrs || log_addrs->num_log_addrs == 0) {
  		cec_adap_unconfigure(adap);
  		adap->log_addrs.num_log_addrs = 0;
  		for (i = 0; i < CEC_MAX_LOG_ADDRS; i++)
  			adap->log_addrs.log_addr[i] = CEC_LOG_ADDR_INVALID;
  		adap->log_addrs.osd_name[0] = '\0';
  		adap->log_addrs.vendor_id = CEC_VENDOR_ID_NONE;
  		adap->log_addrs.cec_version = CEC_OP_CEC_VERSION_2_0;
  		return 0;
  	}
  
  	if (log_addrs->flags & CEC_LOG_ADDRS_FL_CDC_ONLY) {
  		/*
  		 * Sanitize log_addrs fields if a CDC-Only device is
  		 * requested.
  		 */
  		log_addrs->num_log_addrs = 1;
  		log_addrs->osd_name[0] = '\0';
  		log_addrs->vendor_id = CEC_VENDOR_ID_NONE;
  		log_addrs->log_addr_type[0] = CEC_LOG_ADDR_TYPE_UNREGISTERED;
  		/*
  		 * This is just an internal convention since a CDC-Only device
  		 * doesn't have to be a switch. But switches already use
  		 * unregistered, so it makes some kind of sense to pick this
  		 * as the primary device. Since a CDC-Only device never sends
  		 * any 'normal' CEC messages this primary device type is never
  		 * sent over the CEC bus.
  		 */
  		log_addrs->primary_device_type[0] = CEC_OP_PRIM_DEVTYPE_SWITCH;
  		log_addrs->all_device_types[0] = 0;
  		log_addrs->features[0][0] = 0;
  		log_addrs->features[0][1] = 0;
  	}
  
  	/* Ensure the osd name is 0-terminated */
  	log_addrs->osd_name[sizeof(log_addrs->osd_name) - 1] = '\0';
  
  	/* Sanity checks */
  	if (log_addrs->num_log_addrs > adap->available_log_addrs) {
  		dprintk(1, "num_log_addrs > %d\n", adap->available_log_addrs);
  		return -EINVAL;
  	}
  
  	/*
  	 * Vendor ID is a 24 bit number, so check if the value is
  	 * within the correct range.
  	 */
  	if (log_addrs->vendor_id != CEC_VENDOR_ID_NONE &&
  	    (log_addrs->vendor_id & 0xff000000) != 0) {
  		dprintk(1, "invalid vendor ID\n");
  		return -EINVAL;
  	}
  
  	if (log_addrs->cec_version != CEC_OP_CEC_VERSION_1_4 &&
  	    log_addrs->cec_version != CEC_OP_CEC_VERSION_2_0) {
  		dprintk(1, "invalid CEC version\n");
  		return -EINVAL;
  	}
  
  	if (log_addrs->num_log_addrs > 1)
  		for (i = 0; i < log_addrs->num_log_addrs; i++)
  			if (log_addrs->log_addr_type[i] ==
  					CEC_LOG_ADDR_TYPE_UNREGISTERED) {
  				dprintk(1, "num_log_addrs > 1 can't be combined with unregistered LA\n");
  				return -EINVAL;
  			}
  
  	for (i = 0; i < log_addrs->num_log_addrs; i++) {
  		const u8 feature_sz = ARRAY_SIZE(log_addrs->features[0]);
  		u8 *features = log_addrs->features[i];
  		bool op_is_dev_features = false;
  		unsigned int j;
  
  		log_addrs->log_addr[i] = CEC_LOG_ADDR_INVALID;
  		if (log_addrs->log_addr_type[i] > CEC_LOG_ADDR_TYPE_UNREGISTERED) {
  			dprintk(1, "unknown logical address type\n");
  			return -EINVAL;
  		}
  		if (type_mask & (1 << log_addrs->log_addr_type[i])) {
  			dprintk(1, "duplicate logical address type\n");
  			return -EINVAL;
  		}
  		type_mask |= 1 << log_addrs->log_addr_type[i];
  		if ((type_mask & (1 << CEC_LOG_ADDR_TYPE_RECORD)) &&
  		    (type_mask & (1 << CEC_LOG_ADDR_TYPE_PLAYBACK))) {
  			/* Record already contains the playback functionality */
  			dprintk(1, "invalid record + playback combination\n");
  			return -EINVAL;
  		}
  		if (log_addrs->primary_device_type[i] >
  					CEC_OP_PRIM_DEVTYPE_PROCESSOR) {
  			dprintk(1, "unknown primary device type\n");
  			return -EINVAL;
  		}
  		if (log_addrs->primary_device_type[i] == 2) {
  			dprintk(1, "invalid primary device type\n");
  			return -EINVAL;
  		}
  		for (j = 0; j < feature_sz; j++) {
  			if ((features[j] & 0x80) == 0) {
  				if (op_is_dev_features)
  					break;
  				op_is_dev_features = true;
  			}
  		}
  		if (!op_is_dev_features || j == feature_sz) {
  			dprintk(1, "malformed features\n");
  			return -EINVAL;
  		}
  		/* Zero unused part of the feature array */
  		memset(features + j + 1, 0, feature_sz - j - 1);
  	}
  
  	if (log_addrs->cec_version >= CEC_OP_CEC_VERSION_2_0) {
  		if (log_addrs->num_log_addrs > 2) {
  			dprintk(1, "CEC 2.0 allows no more than 2 logical addresses\n");
  			return -EINVAL;
  		}
  		if (log_addrs->num_log_addrs == 2) {
  			if (!(type_mask & ((1 << CEC_LOG_ADDR_TYPE_AUDIOSYSTEM) |
  					   (1 << CEC_LOG_ADDR_TYPE_TV)))) {
  				dprintk(1, "two LAs is only allowed for audiosystem and TV\n");
  				return -EINVAL;
  			}
  			if (!(type_mask & ((1 << CEC_LOG_ADDR_TYPE_PLAYBACK) |
  					   (1 << CEC_LOG_ADDR_TYPE_RECORD)))) {
  				dprintk(1, "an audiosystem/TV can only be combined with record or playback\n");
  				return -EINVAL;
  			}
  		}
  	}
  
  	/* Zero unused LAs */
  	for (i = log_addrs->num_log_addrs; i < CEC_MAX_LOG_ADDRS; i++) {
  		log_addrs->primary_device_type[i] = 0;
  		log_addrs->log_addr_type[i] = 0;
  		log_addrs->all_device_types[i] = 0;
  		memset(log_addrs->features[i], 0,
  		       sizeof(log_addrs->features[i]));
  	}
  
  	log_addrs->log_addr_mask = adap->log_addrs.log_addr_mask;
  	adap->log_addrs = *log_addrs;
  	if (adap->phys_addr != CEC_PHYS_ADDR_INVALID)
  		cec_claim_log_addrs(adap, block);
  	return 0;
  }
  
  int cec_s_log_addrs(struct cec_adapter *adap,
  		    struct cec_log_addrs *log_addrs, bool block)
  {
  	int err;
  
  	mutex_lock(&adap->lock);
  	err = __cec_s_log_addrs(adap, log_addrs, block);
  	mutex_unlock(&adap->lock);
  	return err;
  }
  EXPORT_SYMBOL_GPL(cec_s_log_addrs);
  
  /* High-level core CEC message handling */
  
  /* Fill in the Report Features message */
  static void cec_fill_msg_report_features(struct cec_adapter *adap,
  					 struct cec_msg *msg,
  					 unsigned int la_idx)
  {
  	const struct cec_log_addrs *las = &adap->log_addrs;
  	const u8 *features = las->features[la_idx];
  	bool op_is_dev_features = false;
  	unsigned int idx;
  
  	/* Report Features */
  	msg->msg[0] = (las->log_addr[la_idx] << 4) | 0x0f;
  	msg->len = 4;
  	msg->msg[1] = CEC_MSG_REPORT_FEATURES;
  	msg->msg[2] = adap->log_addrs.cec_version;
  	msg->msg[3] = las->all_device_types[la_idx];
  
  	/* Write RC Profiles first, then Device Features */
  	for (idx = 0; idx < ARRAY_SIZE(las->features[0]); idx++) {
  		msg->msg[msg->len++] = features[idx];
  		if ((features[idx] & CEC_OP_FEAT_EXT) == 0) {
  			if (op_is_dev_features)
  				break;
  			op_is_dev_features = true;
  		}
  	}
  }
  
  /* Transmit the Feature Abort message */
  static int cec_feature_abort_reason(struct cec_adapter *adap,
  				    struct cec_msg *msg, u8 reason)
  {
  	struct cec_msg tx_msg = { };
  
  	/*
  	 * Don't reply with CEC_MSG_FEATURE_ABORT to a CEC_MSG_FEATURE_ABORT
  	 * message!
  	 */
  	if (msg->msg[1] == CEC_MSG_FEATURE_ABORT)
  		return 0;
  	/* Don't Feature Abort messages from 'Unregistered' */
  	if (cec_msg_initiator(msg) == CEC_LOG_ADDR_UNREGISTERED)
  		return 0;
  	cec_msg_set_reply_to(&tx_msg, msg);
  	cec_msg_feature_abort(&tx_msg, msg->msg[1], reason);
  	return cec_transmit_msg(adap, &tx_msg, false);
  }
  
  static int cec_feature_abort(struct cec_adapter *adap, struct cec_msg *msg)
  {
  	return cec_feature_abort_reason(adap, msg,
  					CEC_OP_ABORT_UNRECOGNIZED_OP);
  }
  
  static int cec_feature_refused(struct cec_adapter *adap, struct cec_msg *msg)
  {
  	return cec_feature_abort_reason(adap, msg,
  					CEC_OP_ABORT_REFUSED);
  }
  
  /*
   * Called when a CEC message is received. This function will do any
   * necessary core processing. The is_reply bool is true if this message
   * is a reply to an earlier transmit.
   *
   * The message is either a broadcast message or a valid directed message.
   */
  static int cec_receive_notify(struct cec_adapter *adap, struct cec_msg *msg,
  			      bool is_reply)
  {
  	bool is_broadcast = cec_msg_is_broadcast(msg);
  	u8 dest_laddr = cec_msg_destination(msg);
  	u8 init_laddr = cec_msg_initiator(msg);
  	u8 devtype = cec_log_addr2dev(adap, dest_laddr);
  	int la_idx = cec_log_addr2idx(adap, dest_laddr);
  	bool from_unregistered = init_laddr == 0xf;
  	struct cec_msg tx_cec_msg = { };
  
  	dprintk(2, "%s: %*ph\n", __func__, msg->len, msg->msg);
  
  	/* If this is a CDC-Only device, then ignore any non-CDC messages */
  	if (cec_is_cdc_only(&adap->log_addrs) &&
  	    msg->msg[1] != CEC_MSG_CDC_MESSAGE)
  		return 0;
  
  	if (adap->ops->received) {
  		/* Allow drivers to process the message first */
  		if (adap->ops->received(adap, msg) != -ENOMSG)
  			return 0;
  	}
  
  	/*
  	 * REPORT_PHYSICAL_ADDR, CEC_MSG_USER_CONTROL_PRESSED and
  	 * CEC_MSG_USER_CONTROL_RELEASED messages always have to be
  	 * handled by the CEC core, even if the passthrough mode is on.
  	 * The others are just ignored if passthrough mode is on.
  	 */
  	switch (msg->msg[1]) {
  	case CEC_MSG_GET_CEC_VERSION:
  	case CEC_MSG_ABORT:
  	case CEC_MSG_GIVE_DEVICE_POWER_STATUS:
  	case CEC_MSG_GIVE_OSD_NAME:
  		/*
  		 * These messages reply with a directed message, so ignore if
  		 * the initiator is Unregistered.
  		 */
  		if (!adap->passthrough && from_unregistered)
  			return 0;
  		fallthrough;
  	case CEC_MSG_GIVE_DEVICE_VENDOR_ID:
  	case CEC_MSG_GIVE_FEATURES:
  	case CEC_MSG_GIVE_PHYSICAL_ADDR:
  		/*
  		 * Skip processing these messages if the passthrough mode
  		 * is on.
  		 */
  		if (adap->passthrough)
  			goto skip_processing;
  		/* Ignore if addressing is wrong */
  		if (is_broadcast)
  			return 0;
  		break;
  
  	case CEC_MSG_USER_CONTROL_PRESSED:
  	case CEC_MSG_USER_CONTROL_RELEASED:
  		/* Wrong addressing mode: don't process */
  		if (is_broadcast || from_unregistered)
  			goto skip_processing;
  		break;
  
  	case CEC_MSG_REPORT_PHYSICAL_ADDR:
  		/*
  		 * This message is always processed, regardless of the
  		 * passthrough setting.
  		 *
  		 * Exception: don't process if wrong addressing mode.
  		 */
  		if (!is_broadcast)
  			goto skip_processing;
  		break;
  
  	default:
  		break;
  	}
  
  	cec_msg_set_reply_to(&tx_cec_msg, msg);
  
  	switch (msg->msg[1]) {
  	/* The following messages are processed but still passed through */
  	case CEC_MSG_REPORT_PHYSICAL_ADDR: {
  		u16 pa = (msg->msg[2] << 8) | msg->msg[3];
  
  		dprintk(1, "reported physical address %x.%x.%x.%x for logical address %d\n",
  			cec_phys_addr_exp(pa), init_laddr);
  		break;
  	}
  
  	case CEC_MSG_USER_CONTROL_PRESSED:
  		if (!(adap->capabilities & CEC_CAP_RC) ||
  		    !(adap->log_addrs.flags & CEC_LOG_ADDRS_FL_ALLOW_RC_PASSTHRU))
  			break;
  
  #ifdef CONFIG_MEDIA_CEC_RC
  		switch (msg->msg[2]) {
  		/*
  		 * Play function, this message can have variable length
  		 * depending on the specific play function that is used.
  		 */
  		case CEC_OP_UI_CMD_PLAY_FUNCTION:
  			if (msg->len == 2)
  				rc_keydown(adap->rc, RC_PROTO_CEC,
  					   msg->msg[2], 0);
  			else
  				rc_keydown(adap->rc, RC_PROTO_CEC,
  					   msg->msg[2] << 8 | msg->msg[3], 0);
  			break;
  		/*
  		 * Other function messages that are not handled.
  		 * Currently the RC framework does not allow to supply an
  		 * additional parameter to a keypress. These "keys" contain
  		 * other information such as channel number, an input number
  		 * etc.
  		 * For the time being these messages are not processed by the
  		 * framework and are simply forwarded to the user space.
  		 */
  		case CEC_OP_UI_CMD_SELECT_BROADCAST_TYPE:
  		case CEC_OP_UI_CMD_SELECT_SOUND_PRESENTATION:
  		case CEC_OP_UI_CMD_TUNE_FUNCTION:
  		case CEC_OP_UI_CMD_SELECT_MEDIA_FUNCTION:
  		case CEC_OP_UI_CMD_SELECT_AV_INPUT_FUNCTION:
  		case CEC_OP_UI_CMD_SELECT_AUDIO_INPUT_FUNCTION:
  			break;
  		default:
  			rc_keydown(adap->rc, RC_PROTO_CEC, msg->msg[2], 0);
  			break;
  		}
  #endif
  		break;
  
  	case CEC_MSG_USER_CONTROL_RELEASED:
  		if (!(adap->capabilities & CEC_CAP_RC) ||
  		    !(adap->log_addrs.flags & CEC_LOG_ADDRS_FL_ALLOW_RC_PASSTHRU))
  			break;
  #ifdef CONFIG_MEDIA_CEC_RC
  		rc_keyup(adap->rc);
  #endif
  		break;
  
  	/*
  	 * The remaining messages are only processed if the passthrough mode
  	 * is off.
  	 */
  	case CEC_MSG_GET_CEC_VERSION:
  		cec_msg_cec_version(&tx_cec_msg, adap->log_addrs.cec_version);
  		return cec_transmit_msg(adap, &tx_cec_msg, false);
  
  	case CEC_MSG_GIVE_PHYSICAL_ADDR:
  		/* Do nothing for CEC switches using addr 15 */
  		if (devtype == CEC_OP_PRIM_DEVTYPE_SWITCH && dest_laddr == 15)
  			return 0;
  		cec_msg_report_physical_addr(&tx_cec_msg, adap->phys_addr, devtype);
  		return cec_transmit_msg(adap, &tx_cec_msg, false);
  
  	case CEC_MSG_GIVE_DEVICE_VENDOR_ID:
  		if (adap->log_addrs.vendor_id == CEC_VENDOR_ID_NONE)
  			return cec_feature_abort(adap, msg);
  		cec_msg_device_vendor_id(&tx_cec_msg, adap->log_addrs.vendor_id);
  		return cec_transmit_msg(adap, &tx_cec_msg, false);
  
  	case CEC_MSG_ABORT:
  		/* Do nothing for CEC switches */
  		if (devtype == CEC_OP_PRIM_DEVTYPE_SWITCH)
  			return 0;
  		return cec_feature_refused(adap, msg);
  
  	case CEC_MSG_GIVE_OSD_NAME: {
  		if (adap->log_addrs.osd_name[0] == 0)
  			return cec_feature_abort(adap, msg);
  		cec_msg_set_osd_name(&tx_cec_msg, adap->log_addrs.osd_name);
  		return cec_transmit_msg(adap, &tx_cec_msg, false);
  	}
  
  	case CEC_MSG_GIVE_FEATURES:
  		if (adap->log_addrs.cec_version < CEC_OP_CEC_VERSION_2_0)
  			return cec_feature_abort(adap, msg);
  		cec_fill_msg_report_features(adap, &tx_cec_msg, la_idx);
  		return cec_transmit_msg(adap, &tx_cec_msg, false);
  
  	default:
  		/*
  		 * Unprocessed messages are aborted if userspace isn't doing
  		 * any processing either.
  		 */
  		if (!is_broadcast && !is_reply && !adap->follower_cnt &&
  		    !adap->cec_follower && msg->msg[1] != CEC_MSG_FEATURE_ABORT)
  			return cec_feature_abort(adap, msg);
  		break;
  	}
  
  skip_processing:
  	/* If this was a reply, then we're done, unless otherwise specified */
  	if (is_reply && !(msg->flags & CEC_MSG_FL_REPLY_TO_FOLLOWERS))
  		return 0;
  
  	/*
  	 * Send to the exclusive follower if there is one, otherwise send
  	 * to all followers.
  	 */
  	if (adap->cec_follower)
  		cec_queue_msg_fh(adap->cec_follower, msg);
  	else
  		cec_queue_msg_followers(adap, msg);
  	return 0;
  }
  
  /*
   * Helper functions to keep track of the 'monitor all' use count.
   *
   * These functions are called with adap->lock held.
   */
  int cec_monitor_all_cnt_inc(struct cec_adapter *adap)
  {
  	int ret = 0;
  
  	if (adap->monitor_all_cnt == 0)
  		ret = call_op(adap, adap_monitor_all_enable, 1);
  	if (ret == 0)
  		adap->monitor_all_cnt++;
  	return ret;
  }
  
  void cec_monitor_all_cnt_dec(struct cec_adapter *adap)
  {
  	adap->monitor_all_cnt--;
  	if (adap->monitor_all_cnt == 0)
  		WARN_ON(call_op(adap, adap_monitor_all_enable, 0));
  }
  
  /*
   * Helper functions to keep track of the 'monitor pin' use count.
   *
   * These functions are called with adap->lock held.
   */
  int cec_monitor_pin_cnt_inc(struct cec_adapter *adap)
  {
  	int ret = 0;
  
  	if (adap->monitor_pin_cnt == 0)
  		ret = call_op(adap, adap_monitor_pin_enable, 1);
  	if (ret == 0)
  		adap->monitor_pin_cnt++;
  	return ret;
  }
  
  void cec_monitor_pin_cnt_dec(struct cec_adapter *adap)
  {
  	adap->monitor_pin_cnt--;
  	if (adap->monitor_pin_cnt == 0)
  		WARN_ON(call_op(adap, adap_monitor_pin_enable, 0));
  }
  
  #ifdef CONFIG_DEBUG_FS
  /*
   * Log the current state of the CEC adapter.
   * Very useful for debugging.
   */
  int cec_adap_status(struct seq_file *file, void *priv)
  {
  	struct cec_adapter *adap = dev_get_drvdata(file->private);
  	struct cec_data *data;
  
  	mutex_lock(&adap->lock);
  	seq_printf(file, "configured: %d\n", adap->is_configured);
  	seq_printf(file, "configuring: %d\n", adap->is_configuring);
  	seq_printf(file, "phys_addr: %x.%x.%x.%x\n",
  		   cec_phys_addr_exp(adap->phys_addr));
  	seq_printf(file, "number of LAs: %d\n", adap->log_addrs.num_log_addrs);
  	seq_printf(file, "LA mask: 0x%04x\n", adap->log_addrs.log_addr_mask);
  	if (adap->cec_follower)
  		seq_printf(file, "has CEC follower%s\n",
  			   adap->passthrough ? " (in passthrough mode)" : "");
  	if (adap->cec_initiator)
  		seq_puts(file, "has CEC initiator\n");
  	if (adap->monitor_all_cnt)
  		seq_printf(file, "file handles in Monitor All mode: %u\n",
  			   adap->monitor_all_cnt);
  	if (adap->tx_timeouts) {
  		seq_printf(file, "transmit timeouts: %u\n",
  			   adap->tx_timeouts);
  		adap->tx_timeouts = 0;
  	}
  	data = adap->transmitting;
  	if (data)
  		seq_printf(file, "transmitting message: %*ph (reply: %02x, timeout: %ums)\n",
  			   data->msg.len, data->msg.msg, data->msg.reply,
  			   data->msg.timeout);
  	seq_printf(file, "pending transmits: %u\n", adap->transmit_queue_sz);
  	list_for_each_entry(data, &adap->transmit_queue, list) {
  		seq_printf(file, "queued tx message: %*ph (reply: %02x, timeout: %ums)\n",
  			   data->msg.len, data->msg.msg, data->msg.reply,
  			   data->msg.timeout);
  	}
  	list_for_each_entry(data, &adap->wait_queue, list) {
  		seq_printf(file, "message waiting for reply: %*ph (reply: %02x, timeout: %ums)\n",
  			   data->msg.len, data->msg.msg, data->msg.reply,
  			   data->msg.timeout);
  	}
  
  	call_void_op(adap, adap_status, file);
  	mutex_unlock(&adap->lock);
  	return 0;
  }
  #endif
  