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/*
* i2c.h - definitions for the barebox i2c framework
*
* Copyright (C) 2009 by Marc Kleine-Budde <mkl@pengutronix.de>
*
* This file is released under the GPLv2
*
* Derived from:
* - i2c.h - i.MX I2C driver header file
* Copyright (c) 2008, Darius Augulis <augulis.darius@gmail.com>
* - i2c.h - definitions for the i2c-bus interface
* Copyright (C) 1995-2000 Simon G. Vogl
*
*/
#ifndef I2C_I2C_H
#define I2C_I2C_H
#include <driver.h>
#include <linux/types.h>
#ifndef DOXYGEN_SHOULD_SKIP_THIS
/*
* struct i2c_platform_data - structure of platform data for MXC I2C driver
* @param bitrate Bus speed measured in Hz
*
*/
struct i2c_platform_data {
int bitrate;
};
#define I2C_NAME_SIZE 20
#define I2C_M_RD 0x0001 /* read data, from slave to master */
#define I2C_M_DATA_ONLY 0x0002 /* transfer data bytes only */
#define I2C_M_TEN 0x0010 /* this is a ten bit chip address */
#define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */
#define I2C_M_STOP 0x8000 /* if I2C_FUNC_PROTOCOL_MANGLING */
/**
* struct i2c_msg - an I2C transaction segment beginning with START
*
* An i2c_msg is the low level representation of one segment of an I2C
* transaction. It is visible to drivers in the @i2c_transfer()
* procedure and to I2C adapter drivers through the
* @i2c_adapter.@master_xfer() method.
*
* All I2C adapters implement the standard rules for I2C transactions.
* Each transaction begins with a START. That is followed by the
* slave address, and a bit encoding read versus write. Then follow
* all the data bytes, The transfer terminates with a NAK, or when all
* those bytes have been transferred and ACKed. If this is the last
* message in a group, it is followed by a STOP. Otherwise it is
* followed by the next @i2c_msg transaction segment, beginning with a
* (repeated) START.
*
*/
struct i2c_msg {
__u8 *buf; /**< The buffer into which data is read, or from which it's written. */
__u16 addr; /**< Slave address, seven bits */
__u16 flags; /**< I2C_M_RD is handled by all adapters */
__u16 len; /**< Number of data bytes in @buf being read from or written to the I2C slave address. */
};
/**
* i2c_adapter is the structure used to identify a physical i2c bus
* along with the access algorithms necessary to access it.
*
*/
struct i2c_adapter {
struct device_d dev; /* ptr to device */
int nr; /* bus number */
int (*master_xfer)(struct i2c_adapter *adap, struct i2c_msg *msgs, int num);
struct list_head list;
int retries;
void *algo_data;
};
struct i2c_client {
struct device_d dev;
struct i2c_adapter *adapter;
unsigned short addr;
};
#define to_i2c_client(a) container_of(a, struct i2c_client, dev)
/**
* struct i2c_board_info - template for device creation
*
* I2C doesn't actually support hardware probing, Drivers commonly
* need more information than that, such as chip type, configuration,
* and so on.
*
* i2c_board_info is used to build tables of information listing I2C
* devices that are present. This information is used to grow the
* driver model tree. For mainboards this is done statically using
* i2c_register_board_info(); bus numbers identify adapters that
* aren't yet available. For add-on boards, i2c_new_device() does this
* dynamically with the adapter already known.
*/
struct i2c_board_info {
char type[I2C_NAME_SIZE]; /**< name of device */
unsigned short addr; /**< stored in i2c_client.addr */
void *platform_data; /**< platform data for device */
struct device_node *of_node;
};
/**
* I2C_BOARD_INFO - macro used to list an i2c device and its address
* @dev_type: identifies the device type
* @dev_addr: the device's address on the bus.
*
* This macro initializes essential fields of a struct i2c_board_info,
* declaring what has been provided on a particular board. Optional
* fields (such as associated irq, or device-specific platform_data)
* are provided using conventional syntax.
*/
#define I2C_BOARD_INFO(dev_type, dev_addr) \
.type = dev_type, .addr = (dev_addr)
#ifdef CONFIG_I2C
extern int i2c_register_board_info(int busnum, struct i2c_board_info const *info, unsigned n);
#else
static inline int i2c_register_board_info(int busnum,
struct i2c_board_info const *info, unsigned n)
{
return 0;
}
#endif
extern int i2c_add_numbered_adapter(struct i2c_adapter *adapter);
struct i2c_adapter *i2c_get_adapter(int busnum);
/* For devices that use several addresses, use i2c_new_dummy() to make
* client handles for the extra addresses.
*/
extern struct i2c_client *
i2c_new_dummy(struct i2c_adapter *adap, u16 address);
extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num);
extern int i2c_master_send(struct i2c_client *client, const char *buf, int count);
extern int i2c_master_recv(struct i2c_client *client, char *buf, int count);
#define I2C_ADDR_16_BIT (1 << 31)
extern int i2c_read_reg(struct i2c_client *client, u32 addr, u8 *buf, u16 count);
extern int i2c_write_reg(struct i2c_client *client, u32 addr, const u8 *buf, u16 count);
#endif /* DOXYGEN_SHOULD_SKIP_THIS */
extern struct bus_type i2c_bus;
static inline int i2c_driver_register(struct driver_d *drv)
{
drv->bus = &i2c_bus;
return register_driver(drv);
}
#endif /* I2C_I2C_H */
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