diff options
Diffstat (limited to 'drivers/rtc/rtc-ab-eoz9.c')
| -rw-r--r-- | drivers/rtc/rtc-ab-eoz9.c | 465 |
1 files changed, 465 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ab-eoz9.c b/drivers/rtc/rtc-ab-eoz9.c new file mode 100644 index 000000000000..e4f6e0061ccf --- /dev/null +++ b/drivers/rtc/rtc-ab-eoz9.c @@ -0,0 +1,465 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Real Time Clock driver for AB-RTCMC-32.768kHz-EOZ9 chip. + * Copyright (C) 2019 Orolia + * + */ + +#include <linux/module.h> +#include <linux/rtc.h> +#include <linux/i2c.h> +#include <linux/bcd.h> +#include <linux/of.h> +#include <linux/regmap.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> + +#define ABEOZ9_REG_CTRL1 0x00 +#define ABEOZ9_REG_CTRL1_MASK GENMASK(7, 0) +#define ABEOZ9_REG_CTRL1_WE BIT(0) +#define ABEOZ9_REG_CTRL1_TE BIT(1) +#define ABEOZ9_REG_CTRL1_TAR BIT(2) +#define ABEOZ9_REG_CTRL1_EERE BIT(3) +#define ABEOZ9_REG_CTRL1_SRON BIT(4) +#define ABEOZ9_REG_CTRL1_TD0 BIT(5) +#define ABEOZ9_REG_CTRL1_TD1 BIT(6) +#define ABEOZ9_REG_CTRL1_CLKINT BIT(7) + +#define ABEOZ9_REG_CTRL_INT 0x01 +#define ABEOZ9_REG_CTRL_INT_AIE BIT(0) +#define ABEOZ9_REG_CTRL_INT_TIE BIT(1) +#define ABEOZ9_REG_CTRL_INT_V1IE BIT(2) +#define ABEOZ9_REG_CTRL_INT_V2IE BIT(3) +#define ABEOZ9_REG_CTRL_INT_SRIE BIT(4) + +#define ABEOZ9_REG_CTRL_INT_FLAG 0x02 +#define ABEOZ9_REG_CTRL_INT_FLAG_AF BIT(0) +#define ABEOZ9_REG_CTRL_INT_FLAG_TF BIT(1) +#define ABEOZ9_REG_CTRL_INT_FLAG_V1IF BIT(2) +#define ABEOZ9_REG_CTRL_INT_FLAG_V2IF BIT(3) +#define ABEOZ9_REG_CTRL_INT_FLAG_SRF BIT(4) + +#define ABEOZ9_REG_CTRL_STATUS 0x03 +#define ABEOZ9_REG_CTRL_STATUS_V1F BIT(2) +#define ABEOZ9_REG_CTRL_STATUS_V2F BIT(3) +#define ABEOZ9_REG_CTRL_STATUS_SR BIT(4) +#define ABEOZ9_REG_CTRL_STATUS_PON BIT(5) +#define ABEOZ9_REG_CTRL_STATUS_EEBUSY BIT(7) + +#define ABEOZ9_REG_SEC 0x08 +#define ABEOZ9_REG_MIN 0x09 +#define ABEOZ9_REG_HOURS 0x0A +#define ABEOZ9_HOURS_PM BIT(6) +#define ABEOZ9_REG_DAYS 0x0B +#define ABEOZ9_REG_WEEKDAYS 0x0C +#define ABEOZ9_REG_MONTHS 0x0D +#define ABEOZ9_REG_YEARS 0x0E + +#define ABEOZ9_SEC_LEN 7 + +#define ABEOZ9_REG_REG_TEMP 0x20 +#define ABEOZ953_TEMP_MAX 120 +#define ABEOZ953_TEMP_MIN -60 + +#define ABEOZ9_REG_EEPROM 0x30 +#define ABEOZ9_REG_EEPROM_MASK GENMASK(8, 0) +#define ABEOZ9_REG_EEPROM_THP BIT(0) +#define ABEOZ9_REG_EEPROM_THE BIT(1) +#define ABEOZ9_REG_EEPROM_FD0 BIT(2) +#define ABEOZ9_REG_EEPROM_FD1 BIT(3) +#define ABEOZ9_REG_EEPROM_R1K BIT(4) +#define ABEOZ9_REG_EEPROM_R5K BIT(5) +#define ABEOZ9_REG_EEPROM_R20K BIT(6) +#define ABEOZ9_REG_EEPROM_R80K BIT(7) + +struct abeoz9_rtc_data { + struct rtc_device *rtc; + struct regmap *regmap; + struct device *hwmon_dev; +}; + +static int abeoz9_check_validity(struct device *dev) +{ + struct abeoz9_rtc_data *data = dev_get_drvdata(dev); + struct regmap *regmap = data->regmap; + int ret; + int val; + + ret = regmap_read(regmap, ABEOZ9_REG_CTRL_STATUS, &val); + if (ret < 0) { + dev_err(dev, + "unable to get CTRL_STATUS register (%d)\n", ret); + return ret; + } + + if (val & ABEOZ9_REG_CTRL_STATUS_PON) { + dev_warn(dev, "power-on reset detected, date is invalid\n"); + return -EINVAL; + } + + if (val & ABEOZ9_REG_CTRL_STATUS_V1F) { + dev_warn(dev, + "voltage drops below VLOW1 threshold, date is invalid\n"); + return -EINVAL; + } + + if ((val & ABEOZ9_REG_CTRL_STATUS_V2F)) { + dev_warn(dev, + "voltage drops below VLOW2 threshold, date is invalid\n"); + return -EINVAL; + } + + return 0; +} + +static int abeoz9_reset_validity(struct regmap *regmap) +{ + return regmap_update_bits(regmap, ABEOZ9_REG_CTRL_STATUS, + ABEOZ9_REG_CTRL_STATUS_V1F | + ABEOZ9_REG_CTRL_STATUS_V2F | + ABEOZ9_REG_CTRL_STATUS_PON, + 0); +} + +static int abeoz9_rtc_get_time(struct device *dev, struct rtc_time *tm) +{ + struct abeoz9_rtc_data *data = dev_get_drvdata(dev); + u8 regs[ABEOZ9_SEC_LEN]; + int ret; + + ret = abeoz9_check_validity(dev); + if (ret) + return ret; + + ret = regmap_bulk_read(data->regmap, ABEOZ9_REG_SEC, + regs, + sizeof(regs)); + if (ret) { + dev_err(dev, "reading RTC time failed (%d)\n", ret); + return ret; + } + + tm->tm_sec = bcd2bin(regs[ABEOZ9_REG_SEC - ABEOZ9_REG_SEC] & 0x7F); + tm->tm_min = bcd2bin(regs[ABEOZ9_REG_MIN - ABEOZ9_REG_SEC] & 0x7F); + + if (regs[ABEOZ9_REG_HOURS - ABEOZ9_REG_SEC] & ABEOZ9_HOURS_PM) { + tm->tm_hour = + bcd2bin(regs[ABEOZ9_REG_HOURS - ABEOZ9_REG_SEC] & 0x1f); + if (regs[ABEOZ9_REG_HOURS - ABEOZ9_REG_SEC] & ABEOZ9_HOURS_PM) + tm->tm_hour += 12; + } else { + tm->tm_hour = bcd2bin(regs[ABEOZ9_REG_HOURS - ABEOZ9_REG_SEC]); + } + + tm->tm_mday = bcd2bin(regs[ABEOZ9_REG_DAYS - ABEOZ9_REG_SEC]); + tm->tm_wday = bcd2bin(regs[ABEOZ9_REG_WEEKDAYS - ABEOZ9_REG_SEC]); + tm->tm_mon = bcd2bin(regs[ABEOZ9_REG_MONTHS - ABEOZ9_REG_SEC]) - 1; + tm->tm_year = bcd2bin(regs[ABEOZ9_REG_YEARS - ABEOZ9_REG_SEC]) + 100; + + return ret; +} + +static int abeoz9_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct abeoz9_rtc_data *data = dev_get_drvdata(dev); + struct regmap *regmap = data->regmap; + u8 regs[ABEOZ9_SEC_LEN]; + int ret; + + regs[ABEOZ9_REG_SEC - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_sec); + regs[ABEOZ9_REG_MIN - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_min); + regs[ABEOZ9_REG_HOURS - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_hour); + regs[ABEOZ9_REG_DAYS - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_mday); + regs[ABEOZ9_REG_WEEKDAYS - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_wday); + regs[ABEOZ9_REG_MONTHS - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_mon + 1); + regs[ABEOZ9_REG_YEARS - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_year - 100); + + ret = regmap_bulk_write(data->regmap, ABEOZ9_REG_SEC, + regs, + sizeof(regs)); + + if (ret) { + dev_err(dev, "set RTC time failed (%d)\n", ret); + return ret; + } + + return abeoz9_reset_validity(regmap); +} + +static int abeoz9_trickle_parse_dt(struct device_node *node) +{ + u32 ohms = 0; + + if (of_property_read_u32(node, "trickle-resistor-ohms", &ohms)) + return 0; + + switch (ohms) { + case 1000: + return ABEOZ9_REG_EEPROM_R1K; + case 5000: + return ABEOZ9_REG_EEPROM_R5K; + case 20000: + return ABEOZ9_REG_EEPROM_R20K; + case 80000: + return ABEOZ9_REG_EEPROM_R80K; + default: + return 0; + } +} + +static int abeoz9_rtc_setup(struct device *dev, struct device_node *node) +{ + struct abeoz9_rtc_data *data = dev_get_drvdata(dev); + struct regmap *regmap = data->regmap; + int ret; + + /* Enable Self Recovery, Clock for Watch and EEPROM refresh functions */ + ret = regmap_update_bits(regmap, ABEOZ9_REG_CTRL1, + ABEOZ9_REG_CTRL1_MASK, + ABEOZ9_REG_CTRL1_WE | + ABEOZ9_REG_CTRL1_EERE | + ABEOZ9_REG_CTRL1_SRON); + if (ret < 0) { + dev_err(dev, "unable to set CTRL_1 register (%d)\n", ret); + return ret; + } + + ret = regmap_write(regmap, ABEOZ9_REG_CTRL_INT, 0); + if (ret < 0) { + dev_err(dev, + "unable to set control CTRL_INT register (%d)\n", + ret); + return ret; + } + + ret = regmap_write(regmap, ABEOZ9_REG_CTRL_INT_FLAG, 0); + if (ret < 0) { + dev_err(dev, + "unable to set control CTRL_INT_FLAG register (%d)\n", + ret); + return ret; + } + + ret = abeoz9_trickle_parse_dt(node); + + /* Enable built-in termometer */ + ret |= ABEOZ9_REG_EEPROM_THE; + + ret = regmap_update_bits(regmap, ABEOZ9_REG_EEPROM, + ABEOZ9_REG_EEPROM_MASK, + ret); + if (ret < 0) { + dev_err(dev, "unable to set EEPROM register (%d)\n", ret); + return ret; + } + + return ret; +} + +static const struct rtc_class_ops rtc_ops = { + .read_time = abeoz9_rtc_get_time, + .set_time = abeoz9_rtc_set_time, +}; + +static const struct regmap_config abeoz9_rtc_regmap_config = { + .reg_bits = 8, + .val_bits = 8, +}; + +#if IS_REACHABLE(CONFIG_HWMON) + +static int abeoz9z3_temp_read(struct device *dev, + enum hwmon_sensor_types type, + u32 attr, int channel, long *temp) +{ + struct abeoz9_rtc_data *data = dev_get_drvdata(dev); + struct regmap *regmap = data->regmap; + int ret; + unsigned int val; + + ret = regmap_read(regmap, ABEOZ9_REG_CTRL_STATUS, &val); + if (ret < 0) + return ret; + + if ((val & ABEOZ9_REG_CTRL_STATUS_V1F) || + (val & ABEOZ9_REG_CTRL_STATUS_V2F)) { + dev_err(dev, + "thermometer might be disabled due to low voltage\n"); + return -EINVAL; + } + + switch (attr) { + case hwmon_temp_input: + ret = regmap_read(regmap, ABEOZ9_REG_REG_TEMP, &val); + if (ret < 0) + return ret; + *temp = 1000 * (val + ABEOZ953_TEMP_MIN); + return 0; + case hwmon_temp_max: + *temp = 1000 * ABEOZ953_TEMP_MAX; + return 0; + case hwmon_temp_min: + *temp = 1000 * ABEOZ953_TEMP_MIN; + return 0; + default: + return -EOPNOTSUPP; + } +} + +static umode_t abeoz9_is_visible(const void *data, + enum hwmon_sensor_types type, + u32 attr, int channel) +{ + switch (attr) { + case hwmon_temp_input: + case hwmon_temp_max: + case hwmon_temp_min: + return 0444; + default: + return 0; + } +} + +static const u32 abeoz9_chip_config[] = { + HWMON_C_REGISTER_TZ, + 0 +}; + +static const struct hwmon_channel_info abeoz9_chip = { + .type = hwmon_chip, + .config = abeoz9_chip_config, +}; + +static const u32 abeoz9_temp_config[] = { + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN, + 0 +}; + +static const struct hwmon_channel_info abeoz9_temp = { + .type = hwmon_temp, + .config = abeoz9_temp_config, +}; + +static const struct hwmon_channel_info *abeoz9_info[] = { + &abeoz9_chip, + &abeoz9_temp, + NULL +}; + +static const struct hwmon_ops abeoz9_hwmon_ops = { + .is_visible = abeoz9_is_visible, + .read = abeoz9z3_temp_read, +}; + +static const struct hwmon_chip_info abeoz9_chip_info = { + .ops = &abeoz9_hwmon_ops, + .info = abeoz9_info, +}; + +static void abeoz9_hwmon_register(struct device *dev, + struct abeoz9_rtc_data *data) +{ + data->hwmon_dev = + devm_hwmon_device_register_with_info(dev, + "abeoz9", + data, + &abeoz9_chip_info, + NULL); + if (IS_ERR(data->hwmon_dev)) { + dev_warn(dev, "unable to register hwmon device %ld\n", + PTR_ERR(data->hwmon_dev)); + } +} + +#else + +static void abeoz9_hwmon_register(struct device *dev, + struct abeoz9_rtc_data *data) +{ +} + +#endif + +static int abeoz9_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct abeoz9_rtc_data *data = NULL; + struct device *dev = &client->dev; + struct regmap *regmap; + int ret; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_I2C_BLOCK)) { + ret = -ENODEV; + goto err; + } + + regmap = devm_regmap_init_i2c(client, &abeoz9_rtc_regmap_config); + if (IS_ERR(regmap)) { + ret = PTR_ERR(regmap); + dev_err(dev, "regmap allocation failed: %d\n", ret); + goto err; + } + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) { + ret = -ENOMEM; + goto err; + } + + data->regmap = regmap; + dev_set_drvdata(dev, data); + + ret = abeoz9_rtc_setup(dev, client->dev.of_node); + if (ret) + goto err; + + data->rtc = devm_rtc_allocate_device(dev); + ret = PTR_ERR_OR_ZERO(data->rtc); + if (ret) + goto err; + + data->rtc->ops = &rtc_ops; + data->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; + data->rtc->range_max = RTC_TIMESTAMP_END_2099; + + ret = rtc_register_device(data->rtc); + if (ret) + goto err; + + abeoz9_hwmon_register(dev, data); + return 0; + +err: + dev_err(dev, "unable to register RTC device (%d)\n", ret); + return ret; +} + +#ifdef CONFIG_OF +static const struct of_device_id abeoz9_dt_match[] = { + { .compatible = "abracon,abeoz9" }, + { }, +}; +MODULE_DEVICE_TABLE(of, abeoz9_dt_match); +#endif + +static const struct i2c_device_id abeoz9_id[] = { + { "abeoz9", 0 }, + { } +}; + +static struct i2c_driver abeoz9_driver = { + .driver = { + .name = "rtc-ab-eoz9", + .of_match_table = of_match_ptr(abeoz9_dt_match), + }, + .probe = abeoz9_probe, + .id_table = abeoz9_id, +}; + +module_i2c_driver(abeoz9_driver); + +MODULE_AUTHOR("Artem Panfilov <panfilov.artyom@gmail.com>"); +MODULE_DESCRIPTION("Abracon AB-RTCMC-32.768kHz-EOZ9 RTC driver"); +MODULE_LICENSE("GPL"); |