/* * (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) #if !defined(CONFIG_SYS_MAX_I2C_BUS) #define CONFIG_SYS_MAX_I2C_BUS 2 #endif #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; # elif (defined(CONFIG_AT91RM9200) || \ defined(CONFIG_AT91SAM9260) || defined(CONFIG_AT91SAM9261) || \ defined(CONFIG_AT91SAM9263)) && !defined(CONFIG_AT91_LEGACY) # define I2C_SOFT_DECLARATIONS at91_pio_t *pio = (at91_pio_t *) AT91_PIO_BASE; # 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); void i2c_init_board(void); #ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT void i2c_board_late_init(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; 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_ */