/* * This file is part of the coreboot project. * * Copyright (C) 2014 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; 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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #ifndef _DEVICE_I2C_SIMPLE_H_ #define _DEVICE_I2C_SIMPLE_H_ #include <commonlib/helpers.h> #include <device/i2c.h> int platform_i2c_transfer(unsigned int bus, struct i2c_msg *segments, int count); #define SOFTWARE_I2C_MAX_BUS 10 /* increase as necessary */ struct software_i2c_ops { void (*set_sda)(unsigned int bus, int high); void (*set_scl)(unsigned int bus, int high); int (*get_sda)(unsigned int bus); int (*get_scl)(unsigned int bus); }; extern struct software_i2c_ops *software_i2c[]; int software_i2c_transfer(unsigned int bus, struct i2c_msg *segments, int count); void software_i2c_wedge_ack(unsigned int bus, u8 slave); void software_i2c_wedge_read(unsigned int bus, u8 slave, u8 reg, int bit_count); void software_i2c_wedge_write(unsigned int bus, u8 slave, u8 reg, int bit_count); int i2c_read_field(unsigned int bus, uint8_t slave, uint8_t reg, uint8_t *data, uint8_t mask, uint8_t shift); int i2c_write_field(unsigned int bus, uint8_t slave, uint8_t reg, uint8_t data, uint8_t mask, uint8_t shift); /* * software_i2c is supposed to be a debug feature. It's usually not compiled in, * but when it is it can be dynamically enabled at runtime for certain busses. * Need this ugly stub to arbitrate since I2C device drivers hardcode * 'i2c_transfer()' as their entry point. */ static inline int i2c_transfer(unsigned int bus, struct i2c_msg *segments, int count) { if (CONFIG_SOFTWARE_I2C) if (bus < SOFTWARE_I2C_MAX_BUS && software_i2c[bus]) return software_i2c_transfer(bus, segments, count); return platform_i2c_transfer(bus, segments, count); } /* * Read a raw chunk of data in one segment and one frame. * * [start][slave addr][r][data][stop] */ static inline int i2c_read_raw(unsigned int bus, uint8_t slave, uint8_t *data, int len) { struct i2c_msg seg = { .flags = I2C_M_RD, .slave = slave, .buf = data, .len = len }; return i2c_transfer(bus, &seg, 1); } /* * Write a raw chunk of data in one segment and one frame. * * [start][slave addr][w][data][stop] */ static inline int i2c_write_raw(unsigned int bus, uint8_t slave, uint8_t *data, int len) { struct i2c_msg seg = { .flags = 0, .slave = slave, .buf = data, .len = len }; return i2c_transfer(bus, &seg, 1); } /** * Read multi-bytes with two segments in one frame * * [start][slave addr][w][register addr][start][slave addr][r][data...][stop] */ static inline int i2c_read_bytes(unsigned int bus, uint8_t slave, uint8_t reg, uint8_t *data, int len) { struct i2c_msg seg[2]; seg[0].flags = 0; seg[0].slave = slave; seg[0].buf = ® seg[0].len = 1; seg[1].flags = I2C_M_RD; seg[1].slave = slave; seg[1].buf = data; seg[1].len = len; return i2c_transfer(bus, seg, ARRAY_SIZE(seg)); } /** * Read a byte with two segments in one frame * * [start][slave addr][w][register addr][start][slave addr][r][data][stop] */ static inline int i2c_readb(unsigned int bus, uint8_t slave, uint8_t reg, uint8_t *data) { struct i2c_msg seg[2]; seg[0].flags = 0; seg[0].slave = slave; seg[0].buf = ® seg[0].len = 1; seg[1].flags = I2C_M_RD; seg[1].slave = slave; seg[1].buf = data; seg[1].len = 1; return i2c_transfer(bus, seg, ARRAY_SIZE(seg)); } /** * Write a byte with one segment in one frame. * * [start][slave addr][w][register addr][data][stop] */ static inline int i2c_writeb(unsigned int bus, uint8_t slave, uint8_t reg, uint8_t data) { struct i2c_msg seg; uint8_t buf[] = {reg, data}; seg.flags = 0; seg.slave = slave; seg.buf = buf; seg.len = ARRAY_SIZE(buf); return i2c_transfer(bus, &seg, 1); } #endif /* _DEVICE_I2C_SIMPLE_H_ */