zephyr/drivers/bbram/bbram_emul.c

149 lines
4.0 KiB
C

/*
* Copyright 2021 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT zephyr_bbram_emul
#include <zephyr/drivers/bbram.h>
#include <string.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(bbram, CONFIG_BBRAM_LOG_LEVEL);
/** Device config */
struct bbram_emul_config {
/** BBRAM size (Unit:bytes) */
int size;
};
/** Device data */
struct bbram_emul_data {
/** Memory */
uint8_t *data;
/** Status register */
struct {
/** True if BBRAM is in an invalid state */
uint8_t is_invalid : 1;
/** True if BBRAM incurred a standby power failure */
uint8_t standby_failure : 1;
/** True if BBRAM incurred a power failure */
uint8_t power_failure : 1;
} status;
};
int bbram_emul_set_invalid(const struct device *dev, bool is_invalid)
{
struct bbram_emul_data *data = dev->data;
data->status.is_invalid = is_invalid;
return 0;
}
int bbram_emul_set_standby_power_state(const struct device *dev, bool failure)
{
struct bbram_emul_data *data = dev->data;
data->status.standby_failure = failure;
return 0;
}
int bbram_emul_set_power_state(const struct device *dev, bool failure)
{
struct bbram_emul_data *data = dev->data;
data->status.power_failure = failure;
return 0;
}
static int bbram_emul_check_invalid(const struct device *dev)
{
struct bbram_emul_data *data = dev->data;
bool is_invalid = data->status.is_invalid;
data->status.is_invalid = false;
return is_invalid;
}
static int bbram_emul_check_standby_power(const struct device *dev)
{
struct bbram_emul_data *data = dev->data;
bool failure = data->status.standby_failure;
data->status.standby_failure = false;
return failure;
}
static int bbram_emul_check_power(const struct device *dev)
{
struct bbram_emul_data *data = dev->data;
bool failure = data->status.power_failure;
data->status.power_failure = false;
return failure;
}
static int bbram_emul_get_size(const struct device *dev, size_t *size)
{
const struct bbram_emul_config *config = dev->config;
*size = config->size;
return 0;
}
static int bbram_emul_read(const struct device *dev, size_t offset, size_t size,
uint8_t *data)
{
const struct bbram_emul_config *config = dev->config;
struct bbram_emul_data *dev_data = dev->data;
if (size < 1 || offset + size > config->size || bbram_emul_check_invalid(dev)) {
return -EFAULT;
}
memcpy(data, dev_data->data + offset, size);
return 0;
}
static int bbram_emul_write(const struct device *dev, size_t offset, size_t size,
const uint8_t *data)
{
const struct bbram_emul_config *config = dev->config;
struct bbram_emul_data *dev_data = dev->data;
if (size < 1 || offset + size > config->size || bbram_emul_check_invalid(dev)) {
return -EFAULT;
}
memcpy(dev_data->data + offset, data, size);
return 0;
}
static const struct bbram_driver_api bbram_emul_driver_api = {
.check_invalid = bbram_emul_check_invalid,
.check_standby_power = bbram_emul_check_standby_power,
.check_power = bbram_emul_check_power,
.get_size = bbram_emul_get_size,
.read = bbram_emul_read,
.write = bbram_emul_write,
};
static int bbram_emul_init(const struct device *dev)
{
return 0;
}
#define BBRAM_INIT(inst) \
static uint8_t bbram_emul_mem_##inst[DT_INST_PROP(inst, size)]; \
static struct bbram_emul_data bbram_emul_data_##inst = { \
.data = bbram_emul_mem_##inst, \
}; \
static struct bbram_emul_config bbram_emul_config_##inst = { \
.size = DT_INST_PROP(inst, size), \
}; \
DEVICE_DT_INST_DEFINE(inst, &bbram_emul_init, NULL, &bbram_emul_data_##inst, \
&bbram_emul_config_##inst, PRE_KERNEL_1, CONFIG_BBRAM_INIT_PRIORITY, \
&bbram_emul_driver_api);
DT_INST_FOREACH_STATUS_OKAY(BBRAM_INIT);