mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-26 22:52:18 +00:00
d8a8ea5c47
Signed-off-by: Matthias Fuchs <matthias.fuchs@esd-electronics.com>
151 lines
3.9 KiB
C
151 lines
3.9 KiB
C
/*
|
|
* (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_ */
|