diff options
Diffstat (limited to 'src/include/device/i2c.h')
| -rw-r--r-- | src/include/device/i2c.h | 280 |
1 files changed, 14 insertions, 266 deletions
diff --git a/src/include/device/i2c.h b/src/include/device/i2c.h index bd6dd0c231..d880a7bbae 100644 --- a/src/include/device/i2c.h +++ b/src/include/device/i2c.h @@ -1,14 +1,11 @@ /* - * (C) Copyright 2001 - * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com. + * This file is part of the coreboot project. * - * See file CREDITS for list of people who contributed to this - * project. + * Copyright (C) 2013 Google, Inc. * - * 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 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; version 2 of the License. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -17,265 +14,16 @@ * * 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. + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA */ -#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 */ - -#ifdef CONFIG_I2C_MULTI_BUS -#define MAX_I2C_BUS 2 -#define I2C_MULTI_BUS 1 -#else -#define MAX_I2C_BUS 1 -#define I2C_MULTI_BUS 0 -#endif - -#if !defined(CONFIG_SYS_MAX_I2C_BUS) -#define CONFIG_SYS_MAX_I2C_BUS MAX_I2C_BUS -#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 *) ATMEL_BASE_PIOA; -# 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 { - unsigned char chip; - unsigned char 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 (unsigned char *buf); -int i2x_mux_select_mux(int bus); -int i2c_mux_ident_muxstring_f (unsigned char *buf); -#endif - -/* - * Probe the given I2C chip address. Returns 0 if a chip responded, - * not 0 on failure. - */ -int i2c_probe(unsigned char 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(unsigned char chip, unsigned int addr, int alen, - unsigned char *buffer, int len); -int i2c_write(unsigned char chip, unsigned int addr, int alen, - unsigned char *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 +#ifndef _DEVICE_I2C_H_ +#define _DEVICE_I2C_H_ -#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); - -/* NOTE: These two functions MUST be always_inline to avoid code growth! */ -static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline)); -static inline unsigned int I2C_GET_BUS(void) -{ - return I2C_MULTI_BUS ? i2c_get_bus_num() : 0; -} - -static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline)); -static inline void I2C_SET_BUS(unsigned int bus) -{ - if (I2C_MULTI_BUS) - i2c_set_bus_num(bus); -} - -/* - * Set an early register base for a given i2c peripheral. - * This is used to access a single i2c bus early on in the boot sequence. - * - * @param base: The base address of the i2c peripheral's register map - */ -void i2c_set_early_reg(unsigned int base); - -/** - * Find the I2C bus number by given a FDT I2C node. - * - * @param blob Device tree blbo - * @param node FDT I2C node to find - * @return the number of I2C bus (zero based), or -1 on error - */ -int i2c_get_bus_num_fdt(const void *blob, int node); - -/** - * Reset the I2C bus represented by the given a FDT I2C node. - * - * @param blob Device tree blbo - * @param node FDT I2C node to find - * @return 0 if port was reset, -1 if not found - */ -int i2c_reset_port_fdt(const void *blob, int node); +/* note: chip is the 7-bit I2C address */ +int i2c_read(unsigned bus, unsigned chip, unsigned addr, + unsigned alen, unsigned char *buf, unsigned len); +int i2c_write(unsigned bus, unsigned chip, unsigned addr, + unsigned alen, unsigned char *buf, unsigned len); -#endif /* _I2C_H_ */ +#endif /* _DEVICE_I2C_H_ */ |