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/*
* 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;
}
}
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