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/*
* (C) Copyright 2001
* Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*
* The original I2C interface was
* (C) 2000 by Paolo Scaffardi (arsenio@tin.it)
* AIRVENT SAM s.p.a - RIMINI(ITALY)
* but has been changed substantially.
*/
#ifndef _I2C_H_
#define _I2C_H_
/*
* WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
*
* The implementation MUST NOT use static or global variables if the
* I2C routines are used to read SDRAM configuration information
* because this is done before the memories are initialized. Limited
* use of stack-based variables are OK (the initial stack size is
* limited).
*
* WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
*/
/*
* Configuration items.
*/
#define I2C_RXTX_LEN 128 /* maximum tx/rx buffer length */
#if defined(CONFIG_I2C_MULTI_BUS)
#define CFG_MAX_I2C_BUS 2
#define I2C_GET_BUS() i2c_get_bus_num()
#define I2C_SET_BUS(a) i2c_set_bus_num(a)
#else
#define CFG_MAX_I2C_BUS 1
#define I2C_GET_BUS() 0
#define I2C_SET_BUS(a)
#endif
/* define the I2C bus number for RTC and DTT if not already done */
#if !defined(CFG_RTC_BUS_NUM)
#define CFG_RTC_BUS_NUM 0
#endif
#if !defined(CFG_DTT_BUS_NUM)
#define CFG_DTT_BUS_NUM 0
#endif
#if !defined(CFG_SPD_BUS_NUM)
#define CFG_SPD_BUS_NUM 0
#endif
/*
* Initialization, must be called once on start up, may be called
* repeatedly to change the speed and slave addresses.
*/
void i2c_init(int speed, int slaveaddr);
#ifdef CFG_I2C_INIT_BOARD
void i2c_init_board(void);
#endif
/*
* Probe the given I2C chip address. Returns 0 if a chip responded,
* not 0 on failure.
*/
int i2c_probe(uchar chip);
/*
* Read/Write interface:
* chip: I2C chip address, range 0..127
* addr: Memory (register) address within the chip
* alen: Number of bytes to use for addr (typically 1, 2 for larger
* memories, 0 for register type devices with only one
* register)
* buffer: Where to read/write the data
* len: How many bytes to read/write
*
* Returns: 0 on success, not 0 on failure
*/
int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
/*
* Utility routines to read/write registers.
*/
uchar i2c_reg_read (uchar chip, uchar reg);
void i2c_reg_write(uchar chip, uchar reg, uchar val);
/*
* Functions for setting the current I2C bus and its speed
*/
/*
* i2c_set_bus_num:
*
* Change the active I2C bus. Subsequent read/write calls will
* go to this one.
*
* bus - bus index, zero based
*
* Returns: 0 on success, not 0 on failure
*
*/
int i2c_set_bus_num(unsigned int bus);
/*
* i2c_get_bus_num:
*
* Returns index of currently active I2C bus. Zero-based.
*/
unsigned int i2c_get_bus_num(void);
/*
* i2c_set_bus_speed:
*
* Change the speed of the active I2C bus
*
* speed - bus speed in Hz
*
* Returns: 0 on success, not 0 on failure
*
*/
int i2c_set_bus_speed(unsigned int);
/*
* i2c_get_bus_speed:
*
* Returns speed of currently active I2C bus in Hz
*/
unsigned int i2c_get_bus_speed(void);
#endif /* _I2C_H_ */
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