From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- drivers/rtc/rtc-ds3232.c | 765 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 765 insertions(+) create mode 100644 drivers/rtc/rtc-ds3232.c (limited to 'drivers/rtc/rtc-ds3232.c') diff --git a/drivers/rtc/rtc-ds3232.c b/drivers/rtc/rtc-ds3232.c new file mode 100644 index 000000000..dd31a60c1 --- /dev/null +++ b/drivers/rtc/rtc-ds3232.c @@ -0,0 +1,765 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * RTC client/driver for the Maxim/Dallas DS3232/DS3234 Real-Time Clock + * + * Copyright (C) 2009-2011 Freescale Semiconductor. + * Author: Jack Lan + * Copyright (C) 2008 MIMOMax Wireless Ltd. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DS3232_REG_SECONDS 0x00 +#define DS3232_REG_MINUTES 0x01 +#define DS3232_REG_HOURS 0x02 +#define DS3232_REG_AMPM 0x02 +#define DS3232_REG_DAY 0x03 +#define DS3232_REG_DATE 0x04 +#define DS3232_REG_MONTH 0x05 +#define DS3232_REG_CENTURY 0x05 +#define DS3232_REG_YEAR 0x06 +#define DS3232_REG_ALARM1 0x07 /* Alarm 1 BASE */ +#define DS3232_REG_ALARM2 0x0B /* Alarm 2 BASE */ +#define DS3232_REG_CR 0x0E /* Control register */ +# define DS3232_REG_CR_nEOSC 0x80 +# define DS3232_REG_CR_INTCN 0x04 +# define DS3232_REG_CR_A2IE 0x02 +# define DS3232_REG_CR_A1IE 0x01 + +#define DS3232_REG_SR 0x0F /* control/status register */ +# define DS3232_REG_SR_OSF 0x80 +# define DS3232_REG_SR_BSY 0x04 +# define DS3232_REG_SR_A2F 0x02 +# define DS3232_REG_SR_A1F 0x01 + +#define DS3232_REG_TEMPERATURE 0x11 +#define DS3232_REG_SRAM_START 0x14 +#define DS3232_REG_SRAM_END 0xFF + +#define DS3232_REG_SRAM_SIZE 236 + +struct ds3232 { + struct device *dev; + struct regmap *regmap; + int irq; + struct rtc_device *rtc; + + bool suspended; +}; + +static int ds3232_check_rtc_status(struct device *dev) +{ + struct ds3232 *ds3232 = dev_get_drvdata(dev); + int ret = 0; + int control, stat; + + ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat); + if (ret) + return ret; + + if (stat & DS3232_REG_SR_OSF) + dev_warn(dev, + "oscillator discontinuity flagged, " + "time unreliable\n"); + + stat &= ~(DS3232_REG_SR_OSF | DS3232_REG_SR_A1F | DS3232_REG_SR_A2F); + + ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat); + if (ret) + return ret; + + /* If the alarm is pending, clear it before requesting + * the interrupt, so an interrupt event isn't reported + * before everything is initialized. + */ + + ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control); + if (ret) + return ret; + + control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE); + control |= DS3232_REG_CR_INTCN; + + return regmap_write(ds3232->regmap, DS3232_REG_CR, control); +} + +static int ds3232_read_time(struct device *dev, struct rtc_time *time) +{ + struct ds3232 *ds3232 = dev_get_drvdata(dev); + int ret; + u8 buf[7]; + unsigned int year, month, day, hour, minute, second; + unsigned int week, twelve_hr, am_pm; + unsigned int century, add_century = 0; + + ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_SECONDS, buf, 7); + if (ret) + return ret; + + second = buf[0]; + minute = buf[1]; + hour = buf[2]; + week = buf[3]; + day = buf[4]; + month = buf[5]; + year = buf[6]; + + /* Extract additional information for AM/PM and century */ + + twelve_hr = hour & 0x40; + am_pm = hour & 0x20; + century = month & 0x80; + + /* Write to rtc_time structure */ + + time->tm_sec = bcd2bin(second); + time->tm_min = bcd2bin(minute); + if (twelve_hr) { + /* Convert to 24 hr */ + if (am_pm) + time->tm_hour = bcd2bin(hour & 0x1F) + 12; + else + time->tm_hour = bcd2bin(hour & 0x1F); + } else { + time->tm_hour = bcd2bin(hour); + } + + /* Day of the week in linux range is 0~6 while 1~7 in RTC chip */ + time->tm_wday = bcd2bin(week) - 1; + time->tm_mday = bcd2bin(day); + /* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */ + time->tm_mon = bcd2bin(month & 0x7F) - 1; + if (century) + add_century = 100; + + time->tm_year = bcd2bin(year) + add_century; + + return 0; +} + +static int ds3232_set_time(struct device *dev, struct rtc_time *time) +{ + struct ds3232 *ds3232 = dev_get_drvdata(dev); + u8 buf[7]; + + /* Extract time from rtc_time and load into ds3232*/ + + buf[0] = bin2bcd(time->tm_sec); + buf[1] = bin2bcd(time->tm_min); + buf[2] = bin2bcd(time->tm_hour); + /* Day of the week in linux range is 0~6 while 1~7 in RTC chip */ + buf[3] = bin2bcd(time->tm_wday + 1); + buf[4] = bin2bcd(time->tm_mday); /* Date */ + /* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */ + buf[5] = bin2bcd(time->tm_mon + 1); + if (time->tm_year >= 100) { + buf[5] |= 0x80; + buf[6] = bin2bcd(time->tm_year - 100); + } else { + buf[6] = bin2bcd(time->tm_year); + } + + return regmap_bulk_write(ds3232->regmap, DS3232_REG_SECONDS, buf, 7); +} + +/* + * DS3232 has two alarm, we only use alarm1 + * According to linux specification, only support one-shot alarm + * no periodic alarm mode + */ +static int ds3232_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + struct ds3232 *ds3232 = dev_get_drvdata(dev); + int control, stat; + int ret; + u8 buf[4]; + + ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat); + if (ret) + goto out; + ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control); + if (ret) + goto out; + ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_ALARM1, buf, 4); + if (ret) + goto out; + + alarm->time.tm_sec = bcd2bin(buf[0] & 0x7F); + alarm->time.tm_min = bcd2bin(buf[1] & 0x7F); + alarm->time.tm_hour = bcd2bin(buf[2] & 0x7F); + alarm->time.tm_mday = bcd2bin(buf[3] & 0x7F); + + alarm->enabled = !!(control & DS3232_REG_CR_A1IE); + alarm->pending = !!(stat & DS3232_REG_SR_A1F); + + ret = 0; +out: + return ret; +} + +/* + * linux rtc-module does not support wday alarm + * and only 24h time mode supported indeed + */ +static int ds3232_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + struct ds3232 *ds3232 = dev_get_drvdata(dev); + int control, stat; + int ret; + u8 buf[4]; + + if (ds3232->irq <= 0) + return -EINVAL; + + buf[0] = bin2bcd(alarm->time.tm_sec); + buf[1] = bin2bcd(alarm->time.tm_min); + buf[2] = bin2bcd(alarm->time.tm_hour); + buf[3] = bin2bcd(alarm->time.tm_mday); + + /* clear alarm interrupt enable bit */ + ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control); + if (ret) + goto out; + control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE); + ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control); + if (ret) + goto out; + + /* clear any pending alarm flag */ + ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat); + if (ret) + goto out; + stat &= ~(DS3232_REG_SR_A1F | DS3232_REG_SR_A2F); + ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat); + if (ret) + goto out; + + ret = regmap_bulk_write(ds3232->regmap, DS3232_REG_ALARM1, buf, 4); + if (ret) + goto out; + + if (alarm->enabled) { + control |= DS3232_REG_CR_A1IE; + ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control); + } +out: + return ret; +} + +static int ds3232_update_alarm(struct device *dev, unsigned int enabled) +{ + struct ds3232 *ds3232 = dev_get_drvdata(dev); + int control; + int ret; + + ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control); + if (ret) + return ret; + + if (enabled) + /* enable alarm1 interrupt */ + control |= DS3232_REG_CR_A1IE; + else + /* disable alarm1 interrupt */ + control &= ~(DS3232_REG_CR_A1IE); + ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control); + + return ret; +} + +/* + * Temperature sensor support for ds3232/ds3234 devices. + * A user-initiated temperature conversion is not started by this function, + * so the temperature is updated once every 64 seconds. + */ +static int ds3232_hwmon_read_temp(struct device *dev, long int *mC) +{ + struct ds3232 *ds3232 = dev_get_drvdata(dev); + u8 temp_buf[2]; + s16 temp; + int ret; + + ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_TEMPERATURE, temp_buf, + sizeof(temp_buf)); + if (ret < 0) + return ret; + + /* + * Temperature is represented as a 10-bit code with a resolution of + * 0.25 degree celsius and encoded in two's complement format. + */ + temp = (temp_buf[0] << 8) | temp_buf[1]; + temp >>= 6; + *mC = temp * 250; + + return 0; +} + +static umode_t ds3232_hwmon_is_visible(const void *data, + enum hwmon_sensor_types type, + u32 attr, int channel) +{ + if (type != hwmon_temp) + return 0; + + switch (attr) { + case hwmon_temp_input: + return 0444; + default: + return 0; + } +} + +static int ds3232_hwmon_read(struct device *dev, + enum hwmon_sensor_types type, + u32 attr, int channel, long *temp) +{ + int err; + + switch (attr) { + case hwmon_temp_input: + err = ds3232_hwmon_read_temp(dev, temp); + break; + default: + err = -EOPNOTSUPP; + break; + } + + return err; +} + +static u32 ds3232_hwmon_chip_config[] = { + HWMON_C_REGISTER_TZ, + 0 +}; + +static const struct hwmon_channel_info ds3232_hwmon_chip = { + .type = hwmon_chip, + .config = ds3232_hwmon_chip_config, +}; + +static u32 ds3232_hwmon_temp_config[] = { + HWMON_T_INPUT, + 0 +}; + +static const struct hwmon_channel_info ds3232_hwmon_temp = { + .type = hwmon_temp, + .config = ds3232_hwmon_temp_config, +}; + +static const struct hwmon_channel_info *ds3232_hwmon_info[] = { + &ds3232_hwmon_chip, + &ds3232_hwmon_temp, + NULL +}; + +static const struct hwmon_ops ds3232_hwmon_hwmon_ops = { + .is_visible = ds3232_hwmon_is_visible, + .read = ds3232_hwmon_read, +}; + +static const struct hwmon_chip_info ds3232_hwmon_chip_info = { + .ops = &ds3232_hwmon_hwmon_ops, + .info = ds3232_hwmon_info, +}; + +static void ds3232_hwmon_register(struct device *dev, const char *name) +{ + struct ds3232 *ds3232 = dev_get_drvdata(dev); + struct device *hwmon_dev; + + if (!IS_ENABLED(CONFIG_RTC_DRV_DS3232_HWMON)) + return; + + hwmon_dev = devm_hwmon_device_register_with_info(dev, name, ds3232, + &ds3232_hwmon_chip_info, + NULL); + if (IS_ERR(hwmon_dev)) { + dev_err(dev, "unable to register hwmon device %ld\n", + PTR_ERR(hwmon_dev)); + } +} + +static int ds3232_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + struct ds3232 *ds3232 = dev_get_drvdata(dev); + + if (ds3232->irq <= 0) + return -EINVAL; + + return ds3232_update_alarm(dev, enabled); +} + +static irqreturn_t ds3232_irq(int irq, void *dev_id) +{ + struct device *dev = dev_id; + struct ds3232 *ds3232 = dev_get_drvdata(dev); + int ret; + int stat, control; + + rtc_lock(ds3232->rtc); + + ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat); + if (ret) + goto unlock; + + if (stat & DS3232_REG_SR_A1F) { + ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control); + if (ret) { + dev_warn(ds3232->dev, + "Read Control Register error %d\n", ret); + } else { + /* disable alarm1 interrupt */ + control &= ~(DS3232_REG_CR_A1IE); + ret = regmap_write(ds3232->regmap, DS3232_REG_CR, + control); + if (ret) { + dev_warn(ds3232->dev, + "Write Control Register error %d\n", + ret); + goto unlock; + } + + /* clear the alarm pend flag */ + stat &= ~DS3232_REG_SR_A1F; + ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat); + if (ret) { + dev_warn(ds3232->dev, + "Write Status Register error %d\n", + ret); + goto unlock; + } + + rtc_update_irq(ds3232->rtc, 1, RTC_AF | RTC_IRQF); + } + } + +unlock: + rtc_unlock(ds3232->rtc); + + return IRQ_HANDLED; +} + +static const struct rtc_class_ops ds3232_rtc_ops = { + .read_time = ds3232_read_time, + .set_time = ds3232_set_time, + .read_alarm = ds3232_read_alarm, + .set_alarm = ds3232_set_alarm, + .alarm_irq_enable = ds3232_alarm_irq_enable, +}; + +static int ds3232_nvmem_read(void *priv, unsigned int offset, void *val, + size_t bytes) +{ + struct regmap *ds3232_regmap = (struct regmap *)priv; + + return regmap_bulk_read(ds3232_regmap, DS3232_REG_SRAM_START + offset, + val, bytes); +} + +static int ds3232_nvmem_write(void *priv, unsigned int offset, void *val, + size_t bytes) +{ + struct regmap *ds3232_regmap = (struct regmap *)priv; + + return regmap_bulk_write(ds3232_regmap, DS3232_REG_SRAM_START + offset, + val, bytes); +} + +static int ds3232_probe(struct device *dev, struct regmap *regmap, int irq, + const char *name) +{ + struct ds3232 *ds3232; + int ret; + struct nvmem_config nvmem_cfg = { + .name = "ds3232_sram", + .stride = 1, + .size = DS3232_REG_SRAM_SIZE, + .word_size = 1, + .reg_read = ds3232_nvmem_read, + .reg_write = ds3232_nvmem_write, + .priv = regmap, + .type = NVMEM_TYPE_BATTERY_BACKED + }; + + ds3232 = devm_kzalloc(dev, sizeof(*ds3232), GFP_KERNEL); + if (!ds3232) + return -ENOMEM; + + ds3232->regmap = regmap; + ds3232->irq = irq; + ds3232->dev = dev; + dev_set_drvdata(dev, ds3232); + + ret = ds3232_check_rtc_status(dev); + if (ret) + return ret; + + if (ds3232->irq > 0) + device_init_wakeup(dev, 1); + + ds3232_hwmon_register(dev, name); + + ds3232->rtc = devm_rtc_device_register(dev, name, &ds3232_rtc_ops, + THIS_MODULE); + if (IS_ERR(ds3232->rtc)) + return PTR_ERR(ds3232->rtc); + + ret = devm_rtc_nvmem_register(ds3232->rtc, &nvmem_cfg); + if(ret) + return ret; + + if (ds3232->irq > 0) { + ret = devm_request_threaded_irq(dev, ds3232->irq, NULL, + ds3232_irq, + IRQF_SHARED | IRQF_ONESHOT, + name, dev); + if (ret) { + device_set_wakeup_capable(dev, 0); + ds3232->irq = 0; + dev_err(dev, "unable to request IRQ\n"); + } + } + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int ds3232_suspend(struct device *dev) +{ + struct ds3232 *ds3232 = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) { + if (enable_irq_wake(ds3232->irq)) + dev_warn_once(dev, "Cannot set wakeup source\n"); + } + + return 0; +} + +static int ds3232_resume(struct device *dev) +{ + struct ds3232 *ds3232 = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + disable_irq_wake(ds3232->irq); + + return 0; +} +#endif + +static const struct dev_pm_ops ds3232_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(ds3232_suspend, ds3232_resume) +}; + +#if IS_ENABLED(CONFIG_I2C) + +static int ds3232_i2c_probe(struct i2c_client *client) +{ + struct regmap *regmap; + static const struct regmap_config config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = DS3232_REG_SRAM_END, + }; + + regmap = devm_regmap_init_i2c(client, &config); + if (IS_ERR(regmap)) { + dev_err(&client->dev, "%s: regmap allocation failed: %ld\n", + __func__, PTR_ERR(regmap)); + return PTR_ERR(regmap); + } + + return ds3232_probe(&client->dev, regmap, client->irq, client->name); +} + +static const struct i2c_device_id ds3232_id[] = { + { "ds3232", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ds3232_id); + +static const __maybe_unused struct of_device_id ds3232_of_match[] = { + { .compatible = "dallas,ds3232" }, + { } +}; +MODULE_DEVICE_TABLE(of, ds3232_of_match); + +static struct i2c_driver ds3232_driver = { + .driver = { + .name = "rtc-ds3232", + .of_match_table = of_match_ptr(ds3232_of_match), + .pm = &ds3232_pm_ops, + }, + .probe_new = ds3232_i2c_probe, + .id_table = ds3232_id, +}; + +static int ds3232_register_driver(void) +{ + return i2c_add_driver(&ds3232_driver); +} + +static void ds3232_unregister_driver(void) +{ + i2c_del_driver(&ds3232_driver); +} + +#else + +static int ds3232_register_driver(void) +{ + return 0; +} + +static void ds3232_unregister_driver(void) +{ +} + +#endif + +#if IS_ENABLED(CONFIG_SPI_MASTER) + +static int ds3234_probe(struct spi_device *spi) +{ + int res; + unsigned int tmp; + static const struct regmap_config config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = DS3232_REG_SRAM_END, + .write_flag_mask = 0x80, + }; + struct regmap *regmap; + + regmap = devm_regmap_init_spi(spi, &config); + if (IS_ERR(regmap)) { + dev_err(&spi->dev, "%s: regmap allocation failed: %ld\n", + __func__, PTR_ERR(regmap)); + return PTR_ERR(regmap); + } + + spi->mode = SPI_MODE_3; + spi->bits_per_word = 8; + spi_setup(spi); + + res = regmap_read(regmap, DS3232_REG_SECONDS, &tmp); + if (res) + return res; + + /* Control settings + * + * CONTROL_REG + * BIT 7 6 5 4 3 2 1 0 + * EOSC BBSQW CONV RS2 RS1 INTCN A2IE A1IE + * + * 0 0 0 1 1 1 0 0 + * + * CONTROL_STAT_REG + * BIT 7 6 5 4 3 2 1 0 + * OSF BB32kHz CRATE1 CRATE0 EN32kHz BSY A2F A1F + * + * 1 0 0 0 1 0 0 0 + */ + res = regmap_read(regmap, DS3232_REG_CR, &tmp); + if (res) + return res; + res = regmap_write(regmap, DS3232_REG_CR, tmp & 0x1c); + if (res) + return res; + + res = regmap_read(regmap, DS3232_REG_SR, &tmp); + if (res) + return res; + res = regmap_write(regmap, DS3232_REG_SR, tmp & 0x88); + if (res) + return res; + + /* Print our settings */ + res = regmap_read(regmap, DS3232_REG_CR, &tmp); + if (res) + return res; + dev_info(&spi->dev, "Control Reg: 0x%02x\n", tmp); + + res = regmap_read(regmap, DS3232_REG_SR, &tmp); + if (res) + return res; + dev_info(&spi->dev, "Ctrl/Stat Reg: 0x%02x\n", tmp); + + return ds3232_probe(&spi->dev, regmap, spi->irq, "ds3234"); +} + +static struct spi_driver ds3234_driver = { + .driver = { + .name = "ds3234", + }, + .probe = ds3234_probe, +}; + +static int ds3234_register_driver(void) +{ + return spi_register_driver(&ds3234_driver); +} + +static void ds3234_unregister_driver(void) +{ + spi_unregister_driver(&ds3234_driver); +} + +#else + +static int ds3234_register_driver(void) +{ + return 0; +} + +static void ds3234_unregister_driver(void) +{ +} + +#endif + +static int __init ds323x_init(void) +{ + int ret; + + ret = ds3232_register_driver(); + if (ret) { + pr_err("Failed to register ds3232 driver: %d\n", ret); + return ret; + } + + ret = ds3234_register_driver(); + if (ret) { + pr_err("Failed to register ds3234 driver: %d\n", ret); + ds3232_unregister_driver(); + } + + return ret; +} +module_init(ds323x_init) + +static void __exit ds323x_exit(void) +{ + ds3234_unregister_driver(); + ds3232_unregister_driver(); +} +module_exit(ds323x_exit) + +MODULE_AUTHOR("Srikanth Srinivasan "); +MODULE_AUTHOR("Dennis Aberilla "); +MODULE_DESCRIPTION("Maxim/Dallas DS3232/DS3234 RTC Driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("spi:ds3234"); -- cgit v1.2.3