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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 CONFIG_SYS_MAX_I2C_BUS 2
#define I2C_GET_BUS() i2c_get_bus_num()
#define I2C_SET_BUS(a) i2c_set_bus_num(a)
#else
#define CONFIG_SYS_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(CONFIG_SYS_RTC_BUS_NUM)
#define CONFIG_SYS_RTC_BUS_NUM 0
#endif
#if !defined(CONFIG_SYS_DTT_BUS_NUM)
#define CONFIG_SYS_DTT_BUS_NUM 0
#endif
#if !defined(CONFIG_SYS_SPD_BUS_NUM)
#define CONFIG_SYS_SPD_BUS_NUM 0
#endif
#ifndef I2C_SOFT_DECLARATIONS
# if defined(CONFIG_MPC8260)
# define I2C_SOFT_DECLARATIONS volatile ioport_t *iop = ioport_addr((immap_t *)CONFIG_SYS_IMMR, I2C_PORT);
# elif defined(CONFIG_8xx)
# define I2C_SOFT_DECLARATIONS volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
# else
# define I2C_SOFT_DECLARATIONS
# endif
#endif
#ifdef CONFIG_8xx
/* Set default value for the I2C bus speed on 8xx. In the
* future, we'll define these in all 8xx board config files.
*/
#ifndef CONFIG_SYS_I2C_SPEED
#define CONFIG_SYS_I2C_SPEED 50000
#endif
#endif
/*
* Many boards/controllers/drivers don't support an I2C slave interface so
* provide a default slave address for them for use in common code. A real
* value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
* support a slave interface.
*/
#ifndef CONFIG_SYS_I2C_SLAVE
#define CONFIG_SYS_I2C_SLAVE 0xfe
#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 CONFIG_SYS_I2C_INIT_BOARD
void i2c_init_board(void);
#endif
#if defined(CONFIG_I2C_MUX)
typedef struct _mux {
uchar chip;
uchar channel;
char *name;
struct _mux *next;
} I2C_MUX;
typedef struct _mux_device {
int busid;
I2C_MUX *mux; /* List of muxes, to reach the device */
struct _mux_device *next;
} I2C_MUX_DEVICE;
int i2c_mux_add_device(I2C_MUX_DEVICE *dev);
I2C_MUX_DEVICE *i2c_mux_search_device(int id);
I2C_MUX_DEVICE *i2c_mux_ident_muxstring (uchar *buf);
int i2x_mux_select_mux(int bus);
int i2c_mux_ident_muxstring_f (uchar *buf);
#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.
*/
static inline u8 i2c_reg_read(u8 addr, u8 reg)
{
u8 buf;
#ifdef CONFIG_8xx
/* MPC8xx needs this. Maybe one day we can get rid of it. */
i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
#endif
#ifdef DEBUG
printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
#endif
i2c_read(addr, reg, 1, &buf, 1);
return buf;
}
static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
{
#ifdef CONFIG_8xx
/* MPC8xx needs this. Maybe one day we can get rid of it. */
i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
#endif
#ifdef DEBUG
printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
__func__, addr, reg, val);
#endif
i2c_write(addr, reg, 1, &val, 1);
}
/*
* 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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