include/uapi/linux/cec.h

Source file repositories/reference/linux-study-clean/include/uapi/linux/cec.h

File Facts

System
Linux kernel
Corpus path
include/uapi/linux/cec.h
Extension
.h
Size
43269 bytes
Lines
1237
Domain
Core OS
Bucket
Core Kernel Interface
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

struct cec_msg {
	__u64 tx_ts;
	__u64 rx_ts;
	__u32 len;
	__u32 timeout;
	__u32 sequence;
	__u32 flags;
	__u8 msg[CEC_MAX_MSG_SIZE];
	__u8 reply;
	__u8 rx_status;
	__u8 tx_status;
	__u8 tx_arb_lost_cnt;
	__u8 tx_nack_cnt;
	__u8 tx_low_drive_cnt;
	__u8 tx_error_cnt;
};

/**
 * cec_msg_initiator - return the initiator's logical address.
 * @msg:	the message structure
 */
static inline __u8 cec_msg_initiator(const struct cec_msg *msg)
{
	return msg->msg[0] >> 4;
}

/**
 * cec_msg_destination - return the destination's logical address.
 * @msg:	the message structure
 */
static inline __u8 cec_msg_destination(const struct cec_msg *msg)
{
	return msg->msg[0] & 0xf;
}

/**
 * cec_msg_opcode - return the opcode of the message, -1 for poll
 * @msg:	the message structure
 */
static inline int cec_msg_opcode(const struct cec_msg *msg)
{
	return msg->len > 1 ? msg->msg[1] : -1;
}

/**
 * cec_msg_is_broadcast - return true if this is a broadcast message.
 * @msg:	the message structure
 */
static inline int cec_msg_is_broadcast(const struct cec_msg *msg)
{
	return (msg->msg[0] & 0xf) == 0xf;
}

/**
 * cec_msg_init - initialize the message structure.
 * @msg:	the message structure
 * @initiator:	the logical address of the initiator
 * @destination:the logical address of the destination (0xf for broadcast)
 *
 * The whole structure is zeroed, the len field is set to 1 (i.e. a poll
 * message) and the initiator and destination are filled in.
 */
static inline void cec_msg_init(struct cec_msg *msg,
				__u8 initiator, __u8 destination)
{
	memset(msg, 0, sizeof(*msg));
	msg->msg[0] = (initiator << 4) | destination;
	msg->len = 1;
}

/**
 * cec_msg_set_reply_to - fill in destination/initiator in a reply message.
 * @msg:	the message structure for the reply
 * @orig:	the original message structure
 *
 * Set the msg destination to the orig initiator and the msg initiator to the
 * orig destination. Note that msg and orig may be the same pointer, in which
 * case the change is done in place.
 *
 * It also zeroes the reply, timeout and flags fields.
 */
static inline void cec_msg_set_reply_to(struct cec_msg *msg,
					struct cec_msg *orig)
{
	/* The destination becomes the initiator and vice versa */
	msg->msg[0] = (cec_msg_destination(orig) << 4) |
		      cec_msg_initiator(orig);
	msg->reply = 0;
	msg->timeout = 0;
	msg->flags = 0;

Annotation

Implementation Notes