1*1f045217Swdenk /* 2*1f045217Swdenk * (C) Copyright 2001 3*1f045217Swdenk * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com. 4*1f045217Swdenk * 5*1f045217Swdenk * See file CREDITS for list of people who contributed to this 6*1f045217Swdenk * project. 7*1f045217Swdenk * 8*1f045217Swdenk * This program is free software; you can redistribute it and/or 9*1f045217Swdenk * modify it under the terms of the GNU General Public License as 10*1f045217Swdenk * published by the Free Software Foundation; either version 2 of 11*1f045217Swdenk * the License, or (at your option) any later version. 12*1f045217Swdenk * 13*1f045217Swdenk * This program is distributed in the hope that it will be useful, 14*1f045217Swdenk * but WITHOUT ANY WARRANTY; without even the implied warranty of 15*1f045217Swdenk * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16*1f045217Swdenk * GNU General Public License for more details. 17*1f045217Swdenk * 18*1f045217Swdenk * You should have received a copy of the GNU General Public License 19*1f045217Swdenk * along with this program; if not, write to the Free Software 20*1f045217Swdenk * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 21*1f045217Swdenk * MA 02111-1307 USA 22*1f045217Swdenk * 23*1f045217Swdenk * The original I2C interface was 24*1f045217Swdenk * (C) 2000 by Paolo Scaffardi (arsenio@tin.it) 25*1f045217Swdenk * AIRVENT SAM s.p.a - RIMINI(ITALY) 26*1f045217Swdenk * but has been changed substantially. 27*1f045217Swdenk */ 28*1f045217Swdenk 29*1f045217Swdenk #ifndef _I2C_H_ 30*1f045217Swdenk #define _I2C_H_ 31*1f045217Swdenk 32*1f045217Swdenk /* 33*1f045217Swdenk * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING 34*1f045217Swdenk * 35*1f045217Swdenk * The implementation MUST NOT use static or global variables if the 36*1f045217Swdenk * I2C routines are used to read SDRAM configuration information 37*1f045217Swdenk * because this is done before the memories are initialized. Limited 38*1f045217Swdenk * use of stack-based variables are OK (the initial stack size is 39*1f045217Swdenk * limited). 40*1f045217Swdenk * 41*1f045217Swdenk * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING 42*1f045217Swdenk */ 43*1f045217Swdenk 44*1f045217Swdenk /* 45*1f045217Swdenk * Configuration items. 46*1f045217Swdenk */ 47*1f045217Swdenk #define I2C_RXTX_LEN 128 /* maximum tx/rx buffer length */ 48*1f045217Swdenk 49*1f045217Swdenk /* 50*1f045217Swdenk * Initialization, must be called once on start up, may be called 51*1f045217Swdenk * repeatedly to change the speed and slave addresses. 52*1f045217Swdenk */ 53*1f045217Swdenk void i2c_init(int speed, int slaveaddr); 54*1f045217Swdenk 55*1f045217Swdenk /* 56*1f045217Swdenk * Probe the given I2C chip address. Returns 0 if a chip responded, 57*1f045217Swdenk * not 0 on failure. 58*1f045217Swdenk */ 59*1f045217Swdenk int i2c_probe(uchar chip); 60*1f045217Swdenk 61*1f045217Swdenk /* 62*1f045217Swdenk * Read/Write interface: 63*1f045217Swdenk * chip: I2C chip address, range 0..127 64*1f045217Swdenk * addr: Memory (register) address within the chip 65*1f045217Swdenk * alen: Number of bytes to use for addr (typically 1, 2 for larger 66*1f045217Swdenk * memories, 0 for register type devices with only one 67*1f045217Swdenk * register) 68*1f045217Swdenk * buffer: Where to read/write the data 69*1f045217Swdenk * len: How many bytes to read/write 70*1f045217Swdenk * 71*1f045217Swdenk * Returns: 0 on success, not 0 on failure 72*1f045217Swdenk */ 73*1f045217Swdenk int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len); 74*1f045217Swdenk int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len); 75*1f045217Swdenk 76*1f045217Swdenk /* 77*1f045217Swdenk * Utility routines to read/write registers. 78*1f045217Swdenk */ 79*1f045217Swdenk uchar i2c_reg_read (uchar chip, uchar reg); 80*1f045217Swdenk void i2c_reg_write(uchar chip, uchar reg, uchar val); 81*1f045217Swdenk 82*1f045217Swdenk #endif /* _I2C_H_ */ 83