| /* |
| * This file is part of the coreboot project. |
| * |
| * Copyright 2016 MediaTek 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. |
| */ |
| |
| #include <device/device.h> |
| #include <device/i2c.h> |
| #include <stdint.h> |
| |
| #if ENV_RAMSTAGE |
| /* Return I2C operations for a bus */ |
| static inline const struct i2c_bus_operations *ops_i2c_bus(struct bus *bus) |
| { |
| if (bus && bus->dev && bus->dev->ops) |
| return bus->dev->ops->ops_i2c_bus; |
| return NULL; |
| } |
| |
| int i2c_dev_find_bus(struct device *dev) |
| { |
| const struct i2c_bus_operations *ops; |
| struct bus *pbus; |
| |
| if (!dev) |
| return -1; |
| |
| /* Locate parent bus with I2C controller ops */ |
| pbus = dev->bus; |
| while (pbus && pbus->dev && !ops_i2c_bus(pbus)) |
| if (pbus->dev->bus != pbus) |
| pbus = pbus->dev->bus; |
| |
| /* Check if this I2C controller ops implements dev_to_bus() */ |
| ops = ops_i2c_bus(pbus); |
| if (!ops || !ops->dev_to_bus) |
| return -1; |
| |
| /* Use controller ops to determine the bus number */ |
| return ops->dev_to_bus(pbus->dev); |
| } |
| |
| int i2c_dev_transfer(struct device *dev, struct i2c_seg *segments, int count) |
| { |
| int bus = i2c_dev_find_bus(dev); |
| if (bus < 0) |
| return -1; |
| return i2c_transfer(bus, segments, count); |
| } |
| |
| int i2c_dev_readb(struct device *dev, uint8_t reg, uint8_t *data) |
| { |
| int bus = i2c_dev_find_bus(dev); |
| if (bus < 0) |
| return -1; |
| return i2c_readb(bus, dev->path.i2c.device, reg, data); |
| } |
| |
| int i2c_dev_writeb(struct device *dev, uint8_t reg, uint8_t data) |
| { |
| int bus = i2c_dev_find_bus(dev); |
| if (bus < 0) |
| return -1; |
| return i2c_writeb(bus, dev->path.i2c.device, reg, data); |
| } |
| |
| int i2c_dev_read_bytes(struct device *dev, uint8_t reg, uint8_t *data, int len) |
| { |
| int bus = i2c_dev_find_bus(dev); |
| if (bus < 0) |
| return -1; |
| return i2c_read_bytes(bus, dev->path.i2c.device, reg, data, len); |
| } |
| |
| int i2c_dev_read_raw(struct device *dev, uint8_t *data, int len) |
| { |
| int bus = i2c_dev_find_bus(dev); |
| if (bus < 0) |
| return -1; |
| return i2c_read_raw(bus, dev->path.i2c.device, data, len); |
| } |
| |
| int i2c_dev_write_raw(struct device *dev, uint8_t *data, int len) |
| { |
| int bus = i2c_dev_find_bus(dev); |
| if (bus < 0) |
| return -1; |
| return i2c_write_raw(bus, dev->path.i2c.device, data, len); |
| } |
| #endif |
| |
| int i2c_read_field(unsigned bus, uint8_t chip, uint8_t reg, uint8_t *data, |
| uint8_t mask, uint8_t shift) |
| { |
| int ret; |
| uint8_t buf = 0; |
| |
| ret = i2c_readb(bus, chip, reg, &buf); |
| |
| buf &= (mask << shift); |
| *data = (buf >> shift); |
| |
| return ret; |
| } |
| |
| int i2c_write_field(unsigned bus, uint8_t chip, uint8_t reg, uint8_t data, |
| uint8_t mask, uint8_t shift) |
| { |
| int ret; |
| uint8_t buf = 0; |
| |
| ret = i2c_readb(bus, chip, reg, &buf); |
| |
| buf &= ~(mask << shift); |
| buf |= (data << shift); |
| |
| ret |= i2c_writeb(bus, chip, reg, buf); |
| |
| return ret; |
| } |