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/* Copyright 2019 IBM Corp.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdio.h>
#include <libi2c/libi2c.h>
#include "debug.h"
#include "hwunit.h"
static int kernel_i2c_read(struct i2cbus *i2cbus, uint8_t addr, uint8_t reg, uint16_t size, uint8_t *data)
{
int rc;
uint16_t len = size;
rc = i2c_readn(i2cbus->ctx, addr, reg, &len, data);
if (rc) {
PR_DEBUG("i2c read failed, rc %d\n", rc);
return -1;
}
PR_DEBUG("i2c read %u bytes\n", len);
if (len != size) {
PR_ERROR("i2c read mismatch, expected %u, got %u bytes\n", size, len);
return -1;
}
return 0;
}
static int kernel_i2c_write(struct i2cbus *i2cbus, uint8_t addr, uint8_t reg, uint16_t size, uint8_t *data)
{
int rc;
rc = i2c_writen(i2cbus->ctx, addr, reg, data, size);
if (rc) {
PR_DEBUG("i2c write failed, rc %d\n", rc);
return -1;
}
PR_DEBUG("i2c write %u bytes\n", size);
return 0;
}
static int kernel_i2c_probe(struct pdbg_target *target)
{
struct i2cbus *i2cbus = target_to_i2cbus(target);
const char *i2c_path;
int rc;
i2c_path = pdbg_target_property(target, "device-path", NULL);
assert(i2c_path);
rc = i2c_open(i2c_path, &i2cbus->ctx);
if (rc) {
PR_WARNING("Unable to open i2c driver %s, rc=%d\n", i2c_path, rc);
return -1;
}
return 0;
}
static void kernel_i2c_release(struct pdbg_target *target)
{
struct i2cbus *i2cbus = target_to_i2cbus(target);
i2c_close(i2cbus->ctx);
i2cbus->ctx = NULL;
}
static struct i2cbus kernel_i2c_bus = {
.target = {
.name = "Kernel I2C Bus",
.compatible = "ibm,kernel-i2c-bus",
.class = "i2c_bus",
.probe = kernel_i2c_probe,
.release = kernel_i2c_release,
},
.read = kernel_i2c_read,
.write = kernel_i2c_write,
};
DECLARE_HW_UNIT(kernel_i2c_bus);
__attribute__((constructor))
static void register_i2c_bus(void)
{
pdbg_hwunit_register(PDBG_DEFAULT_BACKEND, &kernel_i2c_bus_hw_unit);
}
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