/* * This file is part of the coreboot 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; 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 <stdlib.h> #include <stdint.h> #include <console/console.h> #include <device/smbus.h> #include <device/i2c_bus.h> struct bus *i2c_link(struct device *const dev) { if (!dev || !dev->bus) return NULL; struct bus *link = dev->bus; while (link) { struct device *const parent = link->dev; if (parent && parent->ops && (parent->ops->ops_i2c_bus || parent->ops->ops_smbus_bus)) break; if (parent && parent->bus) link = parent->bus; else link = NULL; } if (!link) { printk(BIOS_ALERT, "%s Cannot find I2C or SMBus bus operations", dev_path(dev)); } return link; } int i2c_readb(struct device *const dev) { struct device *const busdev = i2c_busdev(dev); if (!busdev) return -1; if (busdev->ops->ops_i2c_bus) { uint8_t val; const struct i2c_msg msg = { .flags = I2C_M_RD, .slave = dev->path.i2c.device, .buf = &val, .len = sizeof(val), }; const int ret = busdev->ops->ops_i2c_bus-> transfer(busdev, &msg, 1); if (ret) return ret; else return val; } else if (busdev->ops->ops_smbus_bus->recv_byte) { return busdev->ops->ops_smbus_bus->recv_byte(dev); } else { printk(BIOS_ERR, "%s Missing ops_smbus_bus->recv_byte", dev_path(busdev)); return -1; } } int i2c_writeb(struct device *const dev, uint8_t val) { struct device *const busdev = i2c_busdev(dev); if (!busdev) return -1; if (busdev->ops->ops_i2c_bus) { const struct i2c_msg msg = { .flags = 0, .slave = dev->path.i2c.device, .buf = &val, .len = sizeof(val), }; return busdev->ops->ops_i2c_bus->transfer(busdev, &msg, 1); } else if (busdev->ops->ops_smbus_bus->send_byte) { return busdev->ops->ops_smbus_bus->send_byte(dev, val); } else { printk(BIOS_ERR, "%s Missing ops_smbus_bus->send_byte", dev_path(busdev)); return -1; } } int i2c_readb_at(struct device *const dev, uint8_t off) { struct device *const busdev = i2c_busdev(dev); if (!busdev) return -1; if (busdev->ops->ops_i2c_bus) { uint8_t val; const struct i2c_msg msg[] = { { .flags = 0, .slave = dev->path.i2c.device, .buf = &off, .len = sizeof(off), }, { .flags = I2C_M_RD, .slave = dev->path.i2c.device, .buf = &val, .len = sizeof(val), }, }; const int ret = busdev->ops->ops_i2c_bus-> transfer(busdev, msg, ARRAY_SIZE(msg)); if (ret) return ret; else return val; } else if (busdev->ops->ops_smbus_bus->read_byte) { return busdev->ops->ops_smbus_bus->read_byte(dev, off); } else { printk(BIOS_ERR, "%s Missing ops_smbus_bus->read_byte", dev_path(busdev)); return -1; } } int i2c_writeb_at(struct device *const dev, const uint8_t off, const uint8_t val) { struct device *const busdev = i2c_busdev(dev); if (!busdev) return -1; if (busdev->ops->ops_i2c_bus) { uint8_t buf[] = { off, val }; const struct i2c_msg msg = { .flags = 0, .slave = dev->path.i2c.device, .buf = buf, .len = sizeof(buf), }; return busdev->ops->ops_i2c_bus->transfer(busdev, &msg, 1); } else if (busdev->ops->ops_smbus_bus->write_byte) { return busdev->ops->ops_smbus_bus->write_byte(dev, off, val); } else { printk(BIOS_ERR, "%s Missing ops_smbus_bus->write_byte", dev_path(busdev)); return -1; } }