zephyr/drivers/charger/emul_sbs_charger.c

154 lines
3.9 KiB
C

/*
* Copyright 2023 Cirrus Logic, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*
* Emulator for SBS 1.1 compliant smart battery charger.
*/
#define DT_DRV_COMPAT sbs_sbs_charger
#include <zephyr/device.h>
#include <zephyr/drivers/emul.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/drivers/i2c_emul.h>
#include <zephyr/logging/log.h>
#include <zephyr/sys/byteorder.h>
#include "sbs_charger.h"
LOG_MODULE_REGISTER(sbs_sbs_charger);
/** Static configuration for the emulator */
struct sbs_charger_emul_cfg {
/** I2C address of emulator */
uint16_t addr;
};
/** Run-time data used by the emulator */
struct sbs_charger_emul_data {
uint16_t reg_charger_mode;
};
static int emul_sbs_charger_reg_write(const struct emul *target, int reg, int val)
{
struct sbs_charger_emul_data *data = target->data;
LOG_INF("write %x = %x", reg, val);
switch (reg) {
case SBS_CHARGER_REG_CHARGER_MODE:
data->reg_charger_mode = val;
break;
default:
LOG_ERR("Unknown write %x", reg);
return -EIO;
}
return 0;
}
static int emul_sbs_charger_reg_read(const struct emul *target, int reg, int *val)
{
switch (reg) {
case SBS_CHARGER_REG_SPEC_INFO:
case SBS_CHARGER_REG_CHARGER_MODE:
case SBS_CHARGER_REG_STATUS:
case SBS_CHARGER_REG_ALARM_WARNING:
/* Arbitrary stub value. */
*val = 1;
break;
default:
LOG_ERR("Unknown register 0x%x read", reg);
return -EIO;
}
LOG_INF("read 0x%x = 0x%x", reg, *val);
return 0;
}
static int sbs_charger_emul_transfer_i2c(const struct emul *target, struct i2c_msg *msgs,
int num_msgs, int addr)
{
/* Largely copied from emul_sbs_gauge.c */
struct sbs_charger_emul_data *data;
unsigned int val;
int reg;
int rc;
data = target->data;
i2c_dump_msgs_rw(target->dev, msgs, num_msgs, addr, false);
switch (num_msgs) {
case 2:
if (msgs->flags & I2C_MSG_READ) {
LOG_ERR("Unexpected read");
return -EIO;
}
if (msgs->len != 1) {
LOG_ERR("Unexpected msg0 length %d", msgs->len);
return -EIO;
}
reg = msgs->buf[0];
/* Now process the 'read' part of the message */
msgs++;
if (msgs->flags & I2C_MSG_READ) {
switch (msgs->len - 1) {
case 1:
rc = emul_sbs_charger_reg_read(target, reg, &val);
if (rc) {
/* Return before writing bad value to message buffer */
return rc;
}
/* SBS uses SMBus, which sends data in little-endian format. */
sys_put_le16(val, msgs->buf);
break;
default:
LOG_ERR("Unexpected msg1 length %d", msgs->len);
return -EIO;
}
} else {
/* We write a word (2 bytes by the SBS spec) */
if (msgs->len != 2) {
LOG_ERR("Unexpected msg1 length %d", msgs->len);
}
uint16_t value = sys_get_le16(msgs->buf);
rc = emul_sbs_charger_reg_write(target, reg, value);
}
break;
default:
LOG_ERR("Invalid number of messages: %d", num_msgs);
return -EIO;
}
return rc;
}
static const struct i2c_emul_api sbs_charger_emul_api_i2c = {
.transfer = sbs_charger_emul_transfer_i2c,
};
static int emul_sbs_sbs_charger_init(const struct emul *target, const struct device *parent)
{
ARG_UNUSED(target);
ARG_UNUSED(parent);
return 0;
}
/*
* Main instantiation macro. SBS Charger Emulator only implemented for I2C
*/
#define SBS_CHARGER_EMUL(n) \
static struct sbs_charger_emul_data sbs_charger_emul_data_##n; \
\
static const struct sbs_charger_emul_cfg sbs_charger_emul_cfg_##n = { \
.addr = DT_INST_REG_ADDR(n), \
}; \
EMUL_DT_INST_DEFINE(n, emul_sbs_sbs_charger_init, &sbs_charger_emul_data_##n, \
&sbs_charger_emul_cfg_##n, &sbs_charger_emul_api_i2c, NULL)
DT_INST_FOREACH_STATUS_OKAY(SBS_CHARGER_EMUL)