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diff --git a/include/media/cec.h b/include/media/cec.h
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+/*
+ * cec - HDMI Consumer Electronics Control support header
+ *
+ * Copyright 2016 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef _MEDIA_CEC_H
+#define _MEDIA_CEC_H
+
+#include <linux/poll.h>
+#include <linux/fs.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/cdev.h>
+#include <linux/kthread.h>
+#include <linux/timer.h>
+#include <linux/cec-funcs.h>
+#include <media/rc-core.h>
+#include <media/cec-edid.h>
+
+/**
+ * struct cec_devnode - cec device node
+ * @dev: cec device
+ * @cdev: cec character device
+ * @parent: parent device
+ * @minor: device node minor number
+ * @registered: the device was correctly registered
+ * @unregistered: the device was unregistered
+ * @fhs_lock: lock to control access to the filehandle list
+ * @fhs: the list of open filehandles (cec_fh)
+ *
+ * This structure represents a cec-related device node.
+ *
+ * The @parent is a physical device. It must be set by core or device drivers
+ * before registering the node.
+ */
+struct cec_devnode {
+ /* sysfs */
+ struct device dev;
+ struct cdev cdev;
+ struct device *parent;
+
+ /* device info */
+ int minor;
+ bool registered;
+ bool unregistered;
+ struct list_head fhs;
+ struct mutex lock;
+};
+
+struct cec_adapter;
+struct cec_data;
+
+struct cec_data {
+ struct list_head list;
+ struct list_head xfer_list;
+ struct cec_adapter *adap;
+ struct cec_msg msg;
+ struct cec_fh *fh;
+ struct delayed_work work;
+ struct completion c;
+ u8 attempts;
+ bool new_initiator;
+ bool blocking;
+ bool completed;
+};
+
+struct cec_msg_entry {
+ struct list_head list;
+ struct cec_msg msg;
+};
+
+#define CEC_NUM_EVENTS CEC_EVENT_LOST_MSGS
+
+struct cec_fh {
+ struct list_head list;
+ struct list_head xfer_list;
+ struct cec_adapter *adap;
+ u8 mode_initiator;
+ u8 mode_follower;
+
+ /* Events */
+ wait_queue_head_t wait;
+ unsigned int pending_events;
+ struct cec_event events[CEC_NUM_EVENTS];
+ struct mutex lock;
+ struct list_head msgs; /* queued messages */
+ unsigned int queued_msgs;
+};
+
+#define CEC_SIGNAL_FREE_TIME_RETRY 3
+#define CEC_SIGNAL_FREE_TIME_NEW_INITIATOR 5
+#define CEC_SIGNAL_FREE_TIME_NEXT_XFER 7
+
+/* The nominal data bit period is 2.4 ms */
+#define CEC_FREE_TIME_TO_USEC(ft) ((ft) * 2400)
+
+struct cec_adap_ops {
+ /* Low-level callbacks */
+ int (*adap_enable)(struct cec_adapter *adap, bool enable);
+ int (*adap_monitor_all_enable)(struct cec_adapter *adap, bool enable);
+ int (*adap_log_addr)(struct cec_adapter *adap, u8 logical_addr);
+ int (*adap_transmit)(struct cec_adapter *adap, u8 attempts,
+ u32 signal_free_time, struct cec_msg *msg);
+ void (*adap_status)(struct cec_adapter *adap, struct seq_file *file);
+
+ /* High-level CEC message callback */
+ int (*received)(struct cec_adapter *adap, struct cec_msg *msg);
+};
+
+/*
+ * The minimum message length you can receive (excepting poll messages) is 2.
+ * With a transfer rate of at most 36 bytes per second this makes 18 messages
+ * per second worst case.
+ *
+ * We queue at most 3 seconds worth of received messages. The CEC specification
+ * requires that messages are replied to within a second, so 3 seconds should
+ * give more than enough margin. Since most messages are actually more than 2
+ * bytes, this is in practice a lot more than 3 seconds.
+ */
+#define CEC_MAX_MSG_RX_QUEUE_SZ (18 * 3)
+
+/*
+ * The transmit queue is limited to 1 second worth of messages (worst case).
+ * Messages can be transmitted by userspace and kernel space. But for both it
+ * makes no sense to have a lot of messages queued up. One second seems
+ * reasonable.
+ */
+#define CEC_MAX_MSG_TX_QUEUE_SZ (18 * 1)
+
+struct cec_adapter {
+ struct module *owner;
+ char name[32];
+ struct cec_devnode devnode;
+ struct mutex lock;
+ struct rc_dev *rc;
+
+ struct list_head transmit_queue;
+ unsigned int transmit_queue_sz;
+ struct list_head wait_queue;
+ struct cec_data *transmitting;
+
+ struct task_struct *kthread_config;
+ struct completion config_completion;
+
+ struct task_struct *kthread;
+ wait_queue_head_t kthread_waitq;
+ wait_queue_head_t waitq;
+
+ const struct cec_adap_ops *ops;
+ void *priv;
+ u32 capabilities;
+ u8 available_log_addrs;
+
+ u16 phys_addr;
+ bool is_configuring;
+ bool is_configured;
+ u32 monitor_all_cnt;
+ u32 follower_cnt;
+ struct cec_fh *cec_follower;
+ struct cec_fh *cec_initiator;
+ bool passthrough;
+ struct cec_log_addrs log_addrs;
+
+ struct dentry *cec_dir;
+ struct dentry *status_file;
+
+ u16 phys_addrs[15];
+ u32 sequence;
+
+ char input_name[32];
+ char input_phys[32];
+ char input_drv[32];
+};
+
+static inline bool cec_has_log_addr(const struct cec_adapter *adap, u8 log_addr)
+{
+ return adap->log_addrs.log_addr_mask & (1 << log_addr);
+}
+
+static inline bool cec_is_sink(const struct cec_adapter *adap)
+{
+ return adap->phys_addr == 0;
+}
+
+#if IS_ENABLED(CONFIG_MEDIA_CEC)
+struct cec_adapter *cec_allocate_adapter(const struct cec_adap_ops *ops,
+ void *priv, const char *name, u32 caps, u8 available_las,
+ struct device *parent);
+int cec_register_adapter(struct cec_adapter *adap);
+void cec_unregister_adapter(struct cec_adapter *adap);
+void cec_delete_adapter(struct cec_adapter *adap);
+
+int cec_s_log_addrs(struct cec_adapter *adap, struct cec_log_addrs *log_addrs,
+ bool block);
+void cec_s_phys_addr(struct cec_adapter *adap, u16 phys_addr,
+ bool block);
+int cec_transmit_msg(struct cec_adapter *adap, struct cec_msg *msg,
+ bool block);
+
+/* Called by the adapter */
+void cec_transmit_done(struct cec_adapter *adap, u8 status, u8 arb_lost_cnt,
+ u8 nack_cnt, u8 low_drive_cnt, u8 error_cnt);
+void cec_received_msg(struct cec_adapter *adap, struct cec_msg *msg);
+
+#else
+
+static inline int cec_register_adapter(struct cec_adapter *adap)
+{
+ return 0;
+}
+
+static inline void cec_unregister_adapter(struct cec_adapter *adap)
+{
+}
+
+static inline void cec_delete_adapter(struct cec_adapter *adap)
+{
+}
+
+static inline void cec_s_phys_addr(struct cec_adapter *adap, u16 phys_addr,
+ bool block)
+{
+}
+
+#endif
+
+#endif /* _MEDIA_CEC_H */