include/uapi/linux/i2c.h

Source file repositories/reference/linux-study-clean/include/uapi/linux/i2c.h

File Facts

System
Linux kernel
Corpus path
include/uapi/linux/i2c.h
Extension
.h
Size
6965 bytes
Lines
166
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 i2c_msg {
	__u16 addr;
	__u16 flags;
#define I2C_M_RD		0x0001	/* guaranteed to be 0x0001! */
#define I2C_M_TEN		0x0010	/* use only if I2C_FUNC_10BIT_ADDR */
#define I2C_M_DMA_SAFE		0x0200	/* use only in kernel space */
#define I2C_M_RECV_LEN		0x0400	/* use only if I2C_FUNC_SMBUS_READ_BLOCK_DATA */
#define I2C_M_NO_RD_ACK		0x0800	/* use only if I2C_FUNC_PROTOCOL_MANGLING */
#define I2C_M_IGNORE_NAK	0x1000	/* use only if I2C_FUNC_PROTOCOL_MANGLING */
#define I2C_M_REV_DIR_ADDR	0x2000	/* use only if I2C_FUNC_PROTOCOL_MANGLING */
#define I2C_M_NOSTART		0x4000	/* use only if I2C_FUNC_NOSTART */
#define I2C_M_STOP		0x8000	/* use only if I2C_FUNC_PROTOCOL_MANGLING */
	__u16 len;
	__u8 *buf;
};

/* To determine what functionality is present */

#define I2C_FUNC_I2C			0x00000001
#define I2C_FUNC_10BIT_ADDR		0x00000002 /* required for I2C_M_TEN */
#define I2C_FUNC_PROTOCOL_MANGLING	0x00000004 /* required for I2C_M_IGNORE_NAK etc. */
#define I2C_FUNC_SMBUS_PEC		0x00000008
#define I2C_FUNC_NOSTART		0x00000010 /* required for I2C_M_NOSTART */
#define I2C_FUNC_SLAVE			0x00000020
#define I2C_FUNC_SMBUS_BLOCK_PROC_CALL	0x00008000 /* SMBus 2.0 or later */
#define I2C_FUNC_SMBUS_QUICK		0x00010000
#define I2C_FUNC_SMBUS_READ_BYTE	0x00020000
#define I2C_FUNC_SMBUS_WRITE_BYTE	0x00040000
#define I2C_FUNC_SMBUS_READ_BYTE_DATA	0x00080000
#define I2C_FUNC_SMBUS_WRITE_BYTE_DATA	0x00100000
#define I2C_FUNC_SMBUS_READ_WORD_DATA	0x00200000
#define I2C_FUNC_SMBUS_WRITE_WORD_DATA	0x00400000
#define I2C_FUNC_SMBUS_PROC_CALL	0x00800000
#define I2C_FUNC_SMBUS_READ_BLOCK_DATA	0x01000000 /* required for I2C_M_RECV_LEN */
#define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
#define I2C_FUNC_SMBUS_READ_I2C_BLOCK	0x04000000 /* I2C-like block xfer  */
#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK	0x08000000 /* w/ 1-byte reg. addr. */
#define I2C_FUNC_SMBUS_HOST_NOTIFY	0x10000000 /* SMBus 2.0 or later */

#define I2C_FUNC_SMBUS_BYTE		(I2C_FUNC_SMBUS_READ_BYTE | \
					 I2C_FUNC_SMBUS_WRITE_BYTE)
#define I2C_FUNC_SMBUS_BYTE_DATA	(I2C_FUNC_SMBUS_READ_BYTE_DATA | \
					 I2C_FUNC_SMBUS_WRITE_BYTE_DATA)
#define I2C_FUNC_SMBUS_WORD_DATA	(I2C_FUNC_SMBUS_READ_WORD_DATA | \
					 I2C_FUNC_SMBUS_WRITE_WORD_DATA)
#define I2C_FUNC_SMBUS_BLOCK_DATA	(I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
					 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA)
#define I2C_FUNC_SMBUS_I2C_BLOCK	(I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
					 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)

#define I2C_FUNC_SMBUS_EMUL		(I2C_FUNC_SMBUS_QUICK | \
					 I2C_FUNC_SMBUS_BYTE | \
					 I2C_FUNC_SMBUS_BYTE_DATA | \
					 I2C_FUNC_SMBUS_WORD_DATA | \
					 I2C_FUNC_SMBUS_PROC_CALL | \
					 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA | \
					 I2C_FUNC_SMBUS_I2C_BLOCK | \
					 I2C_FUNC_SMBUS_PEC)

/* if I2C_M_RECV_LEN is also supported */
#define I2C_FUNC_SMBUS_EMUL_ALL		(I2C_FUNC_SMBUS_EMUL | \
					 I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
					 I2C_FUNC_SMBUS_BLOCK_PROC_CALL)

/*
 * Data for SMBus Messages
 */
#define I2C_SMBUS_BLOCK_MAX	32	/* As specified in SMBus standard */
union i2c_smbus_data {
	__u8 byte;
	__u16 word;
	__u8 block[I2C_SMBUS_BLOCK_MAX + 2]; /* block[0] is used for length */
			       /* and one more for user-space compatibility */
};

/* i2c_smbus_xfer read or write markers */
#define I2C_SMBUS_READ	1
#define I2C_SMBUS_WRITE	0

/* SMBus transaction types (size parameter in the above functions)
   Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
#define I2C_SMBUS_QUICK		    0
#define I2C_SMBUS_BYTE		    1
#define I2C_SMBUS_BYTE_DATA	    2
#define I2C_SMBUS_WORD_DATA	    3
#define I2C_SMBUS_PROC_CALL	    4
#define I2C_SMBUS_BLOCK_DATA	    5
#define I2C_SMBUS_I2C_BLOCK_BROKEN  6
#define I2C_SMBUS_BLOCK_PROC_CALL   7		/* SMBus 2.0 */
#define I2C_SMBUS_I2C_BLOCK_DATA    8

Annotation

Implementation Notes