Primary Git Repository for the Zephyr Project. Zephyr is a new generation, scalable, optimized, secure RTOS for multiple hardware architectures.
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

372 lines
10 KiB

/*
* Copyright (c) 2025 Marcin Lyda <elektromarcin@gmail.com>
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/kernel.h>
#include <zephyr/sys/util.h>
#include <zephyr/logging/log.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/drivers/rtc.h>
#include "rtc_utils.h"
LOG_MODULE_REGISTER(bq32002, CONFIG_RTC_LOG_LEVEL);
#define DT_DRV_COMPAT ti_bq32002
#if DT_NUM_INST_STATUS_OKAY(DT_DRV_COMPAT) == 0
#warning "Texas Instruments BQ32002 RTC driver enabled without any devices"
#endif
/* Registers */
#define BQ32002_SECONDS_REG 0x00
#define BQ32002_MINUTES_REG 0x01
#define BQ32002_CENT_HOURS_REG 0x02
#define BQ32002_DAY_REG 0x03
#define BQ32002_DATE_REG 0x04
#define BQ32002_MONTH_REG 0x05
#define BQ32002_YEARS_REG 0x06
#define BQ32002_CAL_CFG1_REG 0x07
#define BQ32002_CFG2_REG 0x09
#define BQ32002_SF_KEY_1_REG 0x20
#define BQ32002_SF_KEY_2_REG 0x21
#define BQ32002_SFR_REG 0x22
/* Bitmasks */
#define BQ32002_SECONDS_MASK GENMASK(6, 0)
#define BQ32002_MINUTES_MASK GENMASK(6, 0)
#define BQ32002_HOURS_MASK GENMASK(5, 0)
#define BQ32002_DAY_MASK GENMASK(2, 0)
#define BQ32002_DATE_MASK GENMASK(5, 0)
#define BQ32002_MONTH_MASK GENMASK(4, 0)
#define BQ32002_YEAR_MASK GENMASK(7, 0)
#define BQ32002_CAL_MASK GENMASK(4, 0)
#define BQ32002_OSC_STOP_MASK BIT(7)
#define BQ32002_OSC_FAIL_MASK BIT(7)
#define BQ32002_CENT_EN_MASK BIT(7)
#define BQ32002_CENT_MASK BIT(6)
#define BQ32002_OUT_MASK BIT(7)
#define BQ32002_FREQ_TEST_MASK BIT(6)
#define BQ32002_CAL_SIGN_MASK BIT(5)
#define BQ32002_FTF_MASK BIT(0)
/* Keys to unlock special function register */
#define BQ32002_SF_KEY_1 0x5E
#define BQ32002_SF_KEY_2 0xC7
/* BQ32002 counts weekdays from 1 to 7 */
#define BQ32002_DAY_OFFSET -1
/* BQ32002 counts months from 1 to 12 */
#define BQ32002_MONTH_OFFSET -1
/* Year 2000 value represented as tm_year value */
#define BQ32002_TM_YEAR_2000 (2000 - 1900)
/* Calibration constants, see BQ32002 datasheet, Table 12, p.16 */
#define BQ32002_CAL_PPB_PER_LSB_POS 2034 /* 1e9 / 491520 */
#define BQ32002_CAL_PPB_PER_LSB_NEG 4069 /* 1e9 / 245760 */
#define BQ32002_CAL_PPB_MIN (-31 * BQ32002_CAL_PPB_PER_LSB_POS)
#define BQ32002_CAL_PPB_MAX (31 * BQ32002_CAL_PPB_PER_LSB_NEG)
/* IRQ frequency property enum values */
#define BQ32002_IRQ_FREQ_ENUM_1HZ 0
#define BQ32002_IRQ_FREQ_ENUM_512HZ 1
#define BQ32002_IRQ_FREQ_ENUM_DISABLED 2
/* RTC time fields supported by BQ32002 */
#define BQ32002_RTC_TIME_MASK \
(RTC_ALARM_TIME_MASK_SECOND | RTC_ALARM_TIME_MASK_MINUTE | RTC_ALARM_TIME_MASK_HOUR | \
RTC_ALARM_TIME_MASK_MONTH | RTC_ALARM_TIME_MASK_MONTHDAY | RTC_ALARM_TIME_MASK_YEAR | \
RTC_ALARM_TIME_MASK_WEEKDAY)
struct bq32002_config {
struct i2c_dt_spec i2c;
uint8_t irq_freq;
};
struct bq32002_data {
struct k_sem lock;
};
static void bq32002_lock_sem(const struct device *dev)
{
struct bq32002_data *data = dev->data;
(void)k_sem_take(&data->lock, K_FOREVER);
}
static void bq32002_unlock_sem(const struct device *dev)
{
struct bq32002_data *data = dev->data;
k_sem_give(&data->lock);
}
static int bq32002_set_irq_frequency(const struct device *dev)
{
const struct bq32002_config *config = dev->config;
uint8_t sf_regs[3];
uint8_t cfg1_val;
uint8_t cfg2_val;
int err;
switch (config->irq_freq) {
case BQ32002_IRQ_FREQ_ENUM_1HZ:
cfg1_val = BQ32002_FREQ_TEST_MASK;
cfg2_val = BQ32002_FTF_MASK;
break;
case BQ32002_IRQ_FREQ_ENUM_512HZ:
cfg1_val = BQ32002_FREQ_TEST_MASK;
cfg2_val = 0;
break;
default:
cfg1_val = BQ32002_OUT_MASK;
cfg2_val = 0;
break;
}
err = i2c_reg_update_byte_dt(&config->i2c, BQ32002_CAL_CFG1_REG, BQ32002_FREQ_TEST_MASK,
cfg1_val);
if (err) {
return err;
}
/* Update FTF value if frequency output enabled */
if (cfg1_val & BQ32002_FREQ_TEST_MASK) {
sf_regs[0] = BQ32002_SF_KEY_1;
sf_regs[1] = BQ32002_SF_KEY_2;
sf_regs[2] = cfg2_val;
err = i2c_burst_write_dt(&config->i2c, BQ32002_SF_KEY_1_REG, sf_regs,
sizeof(sf_regs));
if (err) {
return err;
}
}
return 0;
}
static int bq32002_set_time(const struct device *dev, const struct rtc_time *timeptr)
{
const struct bq32002_config *config = dev->config;
int err;
uint8_t regs[7];
if ((timeptr == NULL) || !rtc_utils_validate_rtc_time(timeptr, BQ32002_RTC_TIME_MASK)) {
return -EINVAL;
}
bq32002_lock_sem(dev);
/* Update the registers */
regs[0] = bin2bcd(timeptr->tm_sec) & BQ32002_SECONDS_MASK;
regs[1] = bin2bcd(timeptr->tm_min) & BQ32002_MINUTES_MASK; /* Clear oscillator fail flag */
regs[2] = (bin2bcd(timeptr->tm_hour) & BQ32002_HOURS_MASK) | BQ32002_CENT_EN_MASK;
regs[3] = bin2bcd(timeptr->tm_wday - BQ32002_DAY_OFFSET) & BQ32002_DAY_MASK;
regs[4] = bin2bcd(timeptr->tm_mday) & BQ32002_DATE_MASK;
regs[5] = bin2bcd(timeptr->tm_mon - BQ32002_MONTH_OFFSET) & BQ32002_MONTH_MASK;
/* Determine which century we're in */
if (timeptr->tm_year >= BQ32002_TM_YEAR_2000) {
regs[2] |= BQ32002_CENT_MASK;
regs[6] = bin2bcd(timeptr->tm_year - BQ32002_TM_YEAR_2000) & BQ32002_YEAR_MASK;
} else {
regs[6] = bin2bcd(timeptr->tm_year) & BQ32002_YEAR_MASK;
}
/* Write new time to the chip */
err = i2c_burst_write_dt(&config->i2c, BQ32002_SECONDS_REG, regs, sizeof(regs));
bq32002_unlock_sem(dev);
if (!err) {
LOG_DBG("Set time: year: %d, month: %d, month day: %d, week day: %d, hour: %d, "
"minute: %d, second: %d",
timeptr->tm_year, timeptr->tm_mon, timeptr->tm_mday, timeptr->tm_wday,
timeptr->tm_hour, timeptr->tm_min, timeptr->tm_sec);
}
return err;
}
static int bq32002_get_time(const struct device *dev, struct rtc_time *timeptr)
{
const struct bq32002_config *config = dev->config;
int err;
uint8_t reg_val;
uint8_t regs[7];
if (timeptr == NULL) {
return -EINVAL;
}
bq32002_lock_sem(dev);
err = i2c_reg_read_byte_dt(&config->i2c, BQ32002_MINUTES_REG, &reg_val);
if (err) {
goto out_unlock;
}
/* Oscillator failure detected, data might be invalid */
if (reg_val & BQ32002_OSC_FAIL_MASK) {
err = -ENODATA;
goto out_unlock;
}
err = i2c_burst_read_dt(&config->i2c, BQ32002_SECONDS_REG, regs, sizeof(regs));
if (err) {
goto out_unlock;
}
timeptr->tm_sec = bcd2bin(regs[0] & BQ32002_SECONDS_MASK);
timeptr->tm_min = bcd2bin(regs[1] & BQ32002_MINUTES_MASK);
timeptr->tm_hour = bcd2bin(regs[2] & BQ32002_HOURS_MASK);
timeptr->tm_wday = bcd2bin(regs[3] & BQ32002_DAY_MASK) + BQ32002_DAY_OFFSET;
timeptr->tm_mday = bcd2bin(regs[4] & BQ32002_DATE_MASK);
timeptr->tm_mon = bcd2bin(regs[5] & BQ32002_MONTH_MASK) + BQ32002_MONTH_OFFSET;
timeptr->tm_year = bcd2bin(regs[6] & BQ32002_YEAR_MASK);
timeptr->tm_yday = -1; /* Unsupported */
timeptr->tm_isdst = -1; /* Unsupported */
timeptr->tm_nsec = 0; /* Unsupported */
/* Apply century offset */
if (regs[2] & BQ32002_CENT_MASK) {
timeptr->tm_year += BQ32002_TM_YEAR_2000;
}
out_unlock:
bq32002_unlock_sem(dev);
if (!err) {
LOG_DBG("Read time: year: %d, month: %d, month day: %d, week day: %d, hour: %d, "
"minute: "
"%d, second: %d",
timeptr->tm_year, timeptr->tm_mon, timeptr->tm_mday, timeptr->tm_wday,
timeptr->tm_hour, timeptr->tm_min, timeptr->tm_sec);
}
return err;
}
#ifdef CONFIG_RTC_CALIBRATION
static int bq32002_set_calibration(const struct device *dev, int32_t freq_ppb)
{
const struct bq32002_config *config = dev->config;
int err;
uint8_t offset;
uint8_t reg_val;
if ((freq_ppb < BQ32002_CAL_PPB_MIN) || (freq_ppb > BQ32002_CAL_PPB_MAX)) {
LOG_ERR("Calibration value %d ppb out of range", freq_ppb);
return -EINVAL;
}
err = i2c_reg_read_byte_dt(&config->i2c, BQ32002_CAL_CFG1_REG, &reg_val);
if (err) {
return err;
}
reg_val &= ~(BQ32002_CAL_SIGN_MASK | BQ32002_CAL_MASK);
if (freq_ppb > 0) {
reg_val |= BQ32002_CAL_SIGN_MASK; /* Negative sign speeds the oscillator up */
offset =
DIV_ROUND_CLOSEST(freq_ppb, BQ32002_CAL_PPB_PER_LSB_NEG) & BQ32002_CAL_MASK;
} else {
offset = DIV_ROUND_CLOSEST(-freq_ppb, BQ32002_CAL_PPB_PER_LSB_POS) &
BQ32002_CAL_MASK;
}
reg_val |= offset;
err = i2c_reg_write_byte_dt(&config->i2c, BQ32002_CAL_CFG1_REG, reg_val);
if (err) {
return err;
}
LOG_DBG("Set calibration: frequency ppb: %d, offset value: %d, sign: %d", freq_ppb, offset,
freq_ppb > 0);
return 0;
}
static int bq32002_get_calibration(const struct device *dev, int32_t *freq_ppb)
{
const struct bq32002_config *config = dev->config;
uint8_t reg_val;
uint8_t offset;
int err;
err = i2c_reg_read_byte_dt(&config->i2c, BQ32002_CAL_CFG1_REG, &reg_val);
if (err) {
return err;
}
offset = reg_val & BQ32002_CAL_MASK;
if (reg_val & BQ32002_CAL_SIGN_MASK) {
*freq_ppb = offset * BQ32002_CAL_PPB_PER_LSB_NEG;
} else {
*freq_ppb = -offset * BQ32002_CAL_PPB_PER_LSB_POS;
}
LOG_DBG("Get calibration: frequency ppb: %d, offset value: %d, sign: %d", *freq_ppb, offset,
*freq_ppb > 0);
return 0;
}
#endif
static DEVICE_API(rtc, bq32002_driver_api) = {
.set_time = bq32002_set_time,
.get_time = bq32002_get_time,
#ifdef CONFIG_RTC_CALIBRATION
.set_calibration = bq32002_set_calibration,
.get_calibration = bq32002_get_calibration
#endif
};
static int bq32002_init(const struct device *dev)
{
const struct bq32002_config *config = dev->config;
struct bq32002_data *data = dev->data;
int err;
(void)k_sem_init(&data->lock, 1, 1);
if (!i2c_is_ready_dt(&config->i2c)) {
LOG_ERR("I2C bus not ready");
return -ENODEV;
}
/* Start the oscillator */
err = i2c_reg_update_byte_dt(&config->i2c, BQ32002_SECONDS_REG, BQ32002_OSC_STOP_MASK, 0);
if (err) {
return err;
}
/* Configure IRQ output frequency */
err = bq32002_set_irq_frequency(dev);
if (err) {
return err;
}
return 0;
}
#define BQ32002_INIT(inst) \
static struct bq32002_data bq32002_data_##inst; \
static const struct bq32002_config bq32002_config_##inst = { \
.i2c = I2C_DT_SPEC_INST_GET(inst), \
.irq_freq = \
DT_INST_ENUM_IDX_OR(inst, irq_frequency, BQ32002_IRQ_FREQ_ENUM_DISABLED) \
}; \
DEVICE_DT_INST_DEFINE(inst, &bq32002_init, NULL, &bq32002_data_##inst, \
&bq32002_config_##inst, POST_KERNEL, CONFIG_RTC_INIT_PRIORITY, \
&bq32002_driver_api);
DT_INST_FOREACH_STATUS_OKAY(BQ32002_INIT)