blob: bfbe0abe2550f923ad02ed816ea3e4167ea6b532 [file] [log] [blame]
/*
* SPDX-License-Identifier: Apache-2.0
*
* Copyright (c) 2023 Arunmani Alagarsamy
* Author: Arunmani Alagarsamy <arunmani27100@gmail.com>
*/
#include <zephyr/drivers/i2c.h>
#include <zephyr/drivers/rtc.h>
#include <zephyr/logging/log.h>
#include <zephyr/pm/device.h>
#include <zephyr/sys/util.h>
#define DT_DRV_COMPAT maxim_ds1307
LOG_MODULE_REGISTER(ds1307, CONFIG_RTC_LOG_LEVEL);
/* DS1307 registers */
#define DS1307_REG_SECONDS 0x00
#define DS1307_REG_MINUTES 0x01
#define DS1307_REG_HOURS 0x02
#define DS1307_REG_DAY 0x03
#define DS1307_REG_DATE 0x04
#define DS1307_REG_MONTH 0x05
#define DS1307_REG_YEAR 0x06
#define DS1307_REG_CTRL 0x07
#define SECONDS_BITS GENMASK(6, 0)
#define MINUTES_BITS GENMASK(7, 0)
#define HOURS_BITS GENMASK(5, 0)
#define DATE_BITS GENMASK(5, 0)
#define MONTHS_BITS GENMASK(4, 0)
#define WEEKDAY_BITS GENMASK(2, 0)
#define YEAR_BITS GENMASK(7, 0)
#define VALIDATE_24HR BIT(6)
struct ds1307_config {
struct i2c_dt_spec i2c_bus;
};
struct ds1307_data {
struct k_spinlock lock;
};
static int ds1307_set_time(const struct device *dev, const struct rtc_time *tm)
{
int err;
uint8_t regs[7];
struct ds1307_data *data = dev->data;
const struct ds1307_config *config = dev->config;
k_spinlock_key_t key = k_spin_lock(&data->lock);
LOG_DBG("set time: year = %d, mon = %d, mday = %d, wday = %d, hour = %d, "
"min = %d, sec = %d",
tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday, tm->tm_hour, tm->tm_min,
tm->tm_sec);
regs[0] = bin2bcd(tm->tm_sec) & SECONDS_BITS;
regs[1] = bin2bcd(tm->tm_min);
regs[2] = bin2bcd(tm->tm_hour);
regs[3] = bin2bcd(tm->tm_wday);
regs[4] = bin2bcd(tm->tm_mday);
regs[5] = bin2bcd(tm->tm_mon);
regs[6] = bin2bcd((tm->tm_year % 100));
err = i2c_burst_write_dt(&config->i2c_bus, DS1307_REG_SECONDS, regs, sizeof(regs));
k_spin_unlock(&data->lock, key);
return err;
}
static int ds1307_get_time(const struct device *dev, struct rtc_time *timeptr)
{
int err;
uint8_t regs[7];
struct ds1307_data *data = dev->data;
const struct ds1307_config *config = dev->config;
k_spinlock_key_t key = k_spin_lock(&data->lock);
err = i2c_burst_read_dt(&config->i2c_bus, DS1307_REG_SECONDS, regs, sizeof(regs));
if (err != 0) {
goto unlock;
}
timeptr->tm_sec = bcd2bin(regs[0] & SECONDS_BITS);
timeptr->tm_min = bcd2bin(regs[1] & MINUTES_BITS);
timeptr->tm_hour = bcd2bin(regs[2] & HOURS_BITS); /* 24hr mode */
timeptr->tm_wday = bcd2bin(regs[3] & WEEKDAY_BITS);
timeptr->tm_mday = bcd2bin(regs[4] & DATE_BITS);
timeptr->tm_mon = bcd2bin(regs[5] & MONTHS_BITS);
timeptr->tm_year = bcd2bin(regs[6] & YEAR_BITS);
timeptr->tm_year = timeptr->tm_year + 100;
/* Not used */
timeptr->tm_nsec = 0;
timeptr->tm_isdst = -1;
timeptr->tm_yday = -1;
/* Validate the chip in 24hr mode */
if (regs[2] & VALIDATE_24HR) {
err = -ENODATA;
goto unlock;
}
LOG_DBG("get time: year = %d, mon = %d, mday = %d, wday = %d, hour = %d, "
"min = %d, sec = %d",
timeptr->tm_year, timeptr->tm_mon, timeptr->tm_mday, timeptr->tm_wday,
timeptr->tm_hour, timeptr->tm_min, timeptr->tm_sec);
unlock:
k_spin_unlock(&data->lock, key);
return err;
}
static const struct rtc_driver_api ds1307_driver_api = {
.set_time = ds1307_set_time,
.get_time = ds1307_get_time,
};
static int ds1307_init(const struct device *dev)
{
int err;
const struct ds1307_config *config = dev->config;
if (!i2c_is_ready_dt(&config->i2c_bus)) {
LOG_ERR("I2C bus not ready");
return -ENODEV;
}
/* Disable squarewave output */
err = i2c_reg_write_byte_dt(&config->i2c_bus, DS1307_REG_CTRL, 0x00);
if (err < 0) {
LOG_ERR("Error: SQW:%d\n", err);
}
/* Make clock halt = 0 */
err = i2c_reg_write_byte_dt(&config->i2c_bus, DS1307_REG_SECONDS, 0x00);
if (err < 0) {
LOG_ERR("Error: Set clock halt bit:%d\n", err);
}
return 0;
}
#define DS1307_DEFINE(inst) \
static struct ds1307_data ds1307_data_##inst; \
static const struct ds1307_config ds1307_config_##inst = { \
.i2c_bus = I2C_DT_SPEC_INST_GET(inst), \
}; \
DEVICE_DT_INST_DEFINE(inst, &ds1307_init, NULL, &ds1307_data_##inst, \
&ds1307_config_##inst, POST_KERNEL, CONFIG_RTC_INIT_PRIORITY, \
&ds1307_driver_api);
DT_INST_FOREACH_STATUS_OKAY(DS1307_DEFINE)