| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Driver for the Epson RTC module RX-8010 SJ |
| * |
| * Copyright(C) Timesys Corporation 2015 |
| * Copyright(C) General Electric Company 2015 |
| */ |
| |
| #include <linux/bcd.h> |
| #include <linux/bitops.h> |
| #include <linux/i2c.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/regmap.h> |
| #include <linux/rtc.h> |
| |
| #define RX8010_SEC 0x10 |
| #define RX8010_MIN 0x11 |
| #define RX8010_HOUR 0x12 |
| #define RX8010_WDAY 0x13 |
| #define RX8010_MDAY 0x14 |
| #define RX8010_MONTH 0x15 |
| #define RX8010_YEAR 0x16 |
| #define RX8010_RESV17 0x17 |
| #define RX8010_ALMIN 0x18 |
| #define RX8010_ALHOUR 0x19 |
| #define RX8010_ALWDAY 0x1A |
| #define RX8010_TCOUNT0 0x1B |
| #define RX8010_TCOUNT1 0x1C |
| #define RX8010_EXT 0x1D |
| #define RX8010_FLAG 0x1E |
| #define RX8010_CTRL 0x1F |
| /* 0x20 to 0x2F are user registers */ |
| #define RX8010_RESV30 0x30 |
| #define RX8010_RESV31 0x31 |
| #define RX8010_IRQ 0x32 |
| |
| #define RX8010_EXT_WADA BIT(3) |
| |
| #define RX8010_FLAG_VLF BIT(1) |
| #define RX8010_FLAG_AF BIT(3) |
| #define RX8010_FLAG_TF BIT(4) |
| #define RX8010_FLAG_UF BIT(5) |
| |
| #define RX8010_CTRL_AIE BIT(3) |
| #define RX8010_CTRL_UIE BIT(5) |
| #define RX8010_CTRL_STOP BIT(6) |
| #define RX8010_CTRL_TEST BIT(7) |
| |
| #define RX8010_ALARM_AE BIT(7) |
| |
| static const struct i2c_device_id rx8010_id[] = { |
| { "rx8010", 0 }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, rx8010_id); |
| |
| static const __maybe_unused struct of_device_id rx8010_of_match[] = { |
| { .compatible = "epson,rx8010" }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(of, rx8010_of_match); |
| |
| struct rx8010_data { |
| struct regmap *regs; |
| struct rtc_device *rtc; |
| u8 ctrlreg; |
| }; |
| |
| static irqreturn_t rx8010_irq_1_handler(int irq, void *dev_id) |
| { |
| struct i2c_client *client = dev_id; |
| struct rx8010_data *rx8010 = i2c_get_clientdata(client); |
| int flagreg, err; |
| |
| rtc_lock(rx8010->rtc); |
| |
| err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg); |
| if (err) { |
| rtc_unlock(rx8010->rtc); |
| return IRQ_NONE; |
| } |
| |
| if (flagreg & RX8010_FLAG_VLF) |
| dev_warn(&client->dev, "Frequency stop detected\n"); |
| |
| if (flagreg & RX8010_FLAG_TF) { |
| flagreg &= ~RX8010_FLAG_TF; |
| rtc_update_irq(rx8010->rtc, 1, RTC_PF | RTC_IRQF); |
| } |
| |
| if (flagreg & RX8010_FLAG_AF) { |
| flagreg &= ~RX8010_FLAG_AF; |
| rtc_update_irq(rx8010->rtc, 1, RTC_AF | RTC_IRQF); |
| } |
| |
| if (flagreg & RX8010_FLAG_UF) { |
| flagreg &= ~RX8010_FLAG_UF; |
| rtc_update_irq(rx8010->rtc, 1, RTC_UF | RTC_IRQF); |
| } |
| |
| err = regmap_write(rx8010->regs, RX8010_FLAG, flagreg); |
| rtc_unlock(rx8010->rtc); |
| return err ? IRQ_NONE : IRQ_HANDLED; |
| } |
| |
| static int rx8010_get_time(struct device *dev, struct rtc_time *dt) |
| { |
| struct rx8010_data *rx8010 = dev_get_drvdata(dev); |
| u8 date[RX8010_YEAR - RX8010_SEC + 1]; |
| int flagreg, err; |
| |
| err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg); |
| if (err) |
| return err; |
| |
| if (flagreg & RX8010_FLAG_VLF) { |
| dev_warn(dev, "Frequency stop detected\n"); |
| return -EINVAL; |
| } |
| |
| err = regmap_bulk_read(rx8010->regs, RX8010_SEC, date, sizeof(date)); |
| if (err) |
| return err; |
| |
| dt->tm_sec = bcd2bin(date[RX8010_SEC - RX8010_SEC] & 0x7f); |
| dt->tm_min = bcd2bin(date[RX8010_MIN - RX8010_SEC] & 0x7f); |
| dt->tm_hour = bcd2bin(date[RX8010_HOUR - RX8010_SEC] & 0x3f); |
| dt->tm_mday = bcd2bin(date[RX8010_MDAY - RX8010_SEC] & 0x3f); |
| dt->tm_mon = bcd2bin(date[RX8010_MONTH - RX8010_SEC] & 0x1f) - 1; |
| dt->tm_year = bcd2bin(date[RX8010_YEAR - RX8010_SEC]) + 100; |
| dt->tm_wday = ffs(date[RX8010_WDAY - RX8010_SEC] & 0x7f); |
| |
| return 0; |
| } |
| |
| static int rx8010_set_time(struct device *dev, struct rtc_time *dt) |
| { |
| struct rx8010_data *rx8010 = dev_get_drvdata(dev); |
| u8 date[RX8010_YEAR - RX8010_SEC + 1]; |
| int err; |
| |
| /* set STOP bit before changing clock/calendar */ |
| err = regmap_set_bits(rx8010->regs, RX8010_CTRL, RX8010_CTRL_STOP); |
| if (err) |
| return err; |
| |
| date[RX8010_SEC - RX8010_SEC] = bin2bcd(dt->tm_sec); |
| date[RX8010_MIN - RX8010_SEC] = bin2bcd(dt->tm_min); |
| date[RX8010_HOUR - RX8010_SEC] = bin2bcd(dt->tm_hour); |
| date[RX8010_MDAY - RX8010_SEC] = bin2bcd(dt->tm_mday); |
| date[RX8010_MONTH - RX8010_SEC] = bin2bcd(dt->tm_mon + 1); |
| date[RX8010_YEAR - RX8010_SEC] = bin2bcd(dt->tm_year - 100); |
| date[RX8010_WDAY - RX8010_SEC] = bin2bcd(1 << dt->tm_wday); |
| |
| err = regmap_bulk_write(rx8010->regs, RX8010_SEC, date, sizeof(date)); |
| if (err) |
| return err; |
| |
| /* clear STOP bit after changing clock/calendar */ |
| err = regmap_clear_bits(rx8010->regs, RX8010_CTRL, RX8010_CTRL_STOP); |
| if (err) |
| return err; |
| |
| err = regmap_clear_bits(rx8010->regs, RX8010_FLAG, RX8010_FLAG_VLF); |
| if (err) |
| return err; |
| |
| return 0; |
| } |
| |
| static int rx8010_init(struct device *dev) |
| { |
| struct rx8010_data *rx8010 = dev_get_drvdata(dev); |
| u8 ctrl[2]; |
| int need_clear = 0, err; |
| |
| /* Initialize reserved registers as specified in datasheet */ |
| err = regmap_write(rx8010->regs, RX8010_RESV17, 0xD8); |
| if (err) |
| return err; |
| |
| err = regmap_write(rx8010->regs, RX8010_RESV30, 0x00); |
| if (err) |
| return err; |
| |
| err = regmap_write(rx8010->regs, RX8010_RESV31, 0x08); |
| if (err) |
| return err; |
| |
| err = regmap_write(rx8010->regs, RX8010_IRQ, 0x00); |
| if (err) |
| return err; |
| |
| err = regmap_bulk_read(rx8010->regs, RX8010_FLAG, ctrl, 2); |
| if (err) |
| return err; |
| |
| if (ctrl[0] & RX8010_FLAG_VLF) |
| dev_warn(dev, "Frequency stop was detected\n"); |
| |
| if (ctrl[0] & RX8010_FLAG_AF) { |
| dev_warn(dev, "Alarm was detected\n"); |
| need_clear = 1; |
| } |
| |
| if (ctrl[0] & RX8010_FLAG_TF) |
| need_clear = 1; |
| |
| if (ctrl[0] & RX8010_FLAG_UF) |
| need_clear = 1; |
| |
| if (need_clear) { |
| ctrl[0] &= ~(RX8010_FLAG_AF | RX8010_FLAG_TF | RX8010_FLAG_UF); |
| err = regmap_write(rx8010->regs, RX8010_FLAG, ctrl[0]); |
| if (err) |
| return err; |
| } |
| |
| rx8010->ctrlreg = (ctrl[1] & ~RX8010_CTRL_TEST); |
| |
| return 0; |
| } |
| |
| static int rx8010_read_alarm(struct device *dev, struct rtc_wkalrm *t) |
| { |
| struct rx8010_data *rx8010 = dev_get_drvdata(dev); |
| u8 alarmvals[3]; |
| int flagreg, err; |
| |
| err = regmap_bulk_read(rx8010->regs, RX8010_ALMIN, alarmvals, 3); |
| if (err) |
| return err; |
| |
| err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg); |
| if (err) |
| return err; |
| |
| t->time.tm_sec = 0; |
| t->time.tm_min = bcd2bin(alarmvals[0] & 0x7f); |
| t->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f); |
| |
| if (!(alarmvals[2] & RX8010_ALARM_AE)) |
| t->time.tm_mday = bcd2bin(alarmvals[2] & 0x7f); |
| |
| t->enabled = !!(rx8010->ctrlreg & RX8010_CTRL_AIE); |
| t->pending = (flagreg & RX8010_FLAG_AF) && t->enabled; |
| |
| return 0; |
| } |
| |
| static int rx8010_set_alarm(struct device *dev, struct rtc_wkalrm *t) |
| { |
| struct rx8010_data *rx8010 = dev_get_drvdata(dev); |
| u8 alarmvals[3]; |
| int err; |
| |
| if (rx8010->ctrlreg & (RX8010_CTRL_AIE | RX8010_CTRL_UIE)) { |
| rx8010->ctrlreg &= ~(RX8010_CTRL_AIE | RX8010_CTRL_UIE); |
| err = regmap_write(rx8010->regs, RX8010_CTRL, rx8010->ctrlreg); |
| if (err) |
| return err; |
| } |
| |
| err = regmap_clear_bits(rx8010->regs, RX8010_FLAG, RX8010_FLAG_AF); |
| if (err) |
| return err; |
| |
| alarmvals[0] = bin2bcd(t->time.tm_min); |
| alarmvals[1] = bin2bcd(t->time.tm_hour); |
| alarmvals[2] = bin2bcd(t->time.tm_mday); |
| |
| err = regmap_bulk_write(rx8010->regs, RX8010_ALMIN, alarmvals, 2); |
| if (err) |
| return err; |
| |
| err = regmap_clear_bits(rx8010->regs, RX8010_EXT, RX8010_EXT_WADA); |
| if (err) |
| return err; |
| |
| if (alarmvals[2] == 0) |
| alarmvals[2] |= RX8010_ALARM_AE; |
| |
| err = regmap_write(rx8010->regs, RX8010_ALWDAY, alarmvals[2]); |
| if (err) |
| return err; |
| |
| if (t->enabled) { |
| if (rx8010->rtc->uie_rtctimer.enabled) |
| rx8010->ctrlreg |= RX8010_CTRL_UIE; |
| if (rx8010->rtc->aie_timer.enabled) |
| rx8010->ctrlreg |= |
| (RX8010_CTRL_AIE | RX8010_CTRL_UIE); |
| |
| err = regmap_write(rx8010->regs, RX8010_CTRL, rx8010->ctrlreg); |
| if (err) |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| static int rx8010_alarm_irq_enable(struct device *dev, |
| unsigned int enabled) |
| { |
| struct rx8010_data *rx8010 = dev_get_drvdata(dev); |
| int err; |
| u8 ctrl; |
| |
| ctrl = rx8010->ctrlreg; |
| |
| if (enabled) { |
| if (rx8010->rtc->uie_rtctimer.enabled) |
| ctrl |= RX8010_CTRL_UIE; |
| if (rx8010->rtc->aie_timer.enabled) |
| ctrl |= (RX8010_CTRL_AIE | RX8010_CTRL_UIE); |
| } else { |
| if (!rx8010->rtc->uie_rtctimer.enabled) |
| ctrl &= ~RX8010_CTRL_UIE; |
| if (!rx8010->rtc->aie_timer.enabled) |
| ctrl &= ~RX8010_CTRL_AIE; |
| } |
| |
| err = regmap_clear_bits(rx8010->regs, RX8010_FLAG, RX8010_FLAG_AF); |
| if (err) |
| return err; |
| |
| if (ctrl != rx8010->ctrlreg) { |
| rx8010->ctrlreg = ctrl; |
| err = regmap_write(rx8010->regs, RX8010_CTRL, rx8010->ctrlreg); |
| if (err) |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| static int rx8010_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) |
| { |
| struct rx8010_data *rx8010 = dev_get_drvdata(dev); |
| int tmp, flagreg, err; |
| |
| switch (cmd) { |
| case RTC_VL_READ: |
| err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg); |
| if (err) |
| return err; |
| |
| tmp = flagreg & RX8010_FLAG_VLF ? RTC_VL_DATA_INVALID : 0; |
| return put_user(tmp, (unsigned int __user *)arg); |
| |
| default: |
| return -ENOIOCTLCMD; |
| } |
| } |
| |
| static const struct rtc_class_ops rx8010_rtc_ops = { |
| .read_time = rx8010_get_time, |
| .set_time = rx8010_set_time, |
| .ioctl = rx8010_ioctl, |
| .read_alarm = rx8010_read_alarm, |
| .set_alarm = rx8010_set_alarm, |
| .alarm_irq_enable = rx8010_alarm_irq_enable, |
| }; |
| |
| static const struct regmap_config rx8010_regmap_config = { |
| .name = "rx8010-rtc", |
| .reg_bits = 8, |
| .val_bits = 8, |
| }; |
| |
| static int rx8010_probe(struct i2c_client *client) |
| { |
| struct device *dev = &client->dev; |
| struct rx8010_data *rx8010; |
| int err = 0; |
| |
| rx8010 = devm_kzalloc(dev, sizeof(*rx8010), GFP_KERNEL); |
| if (!rx8010) |
| return -ENOMEM; |
| |
| i2c_set_clientdata(client, rx8010); |
| |
| rx8010->regs = devm_regmap_init_i2c(client, &rx8010_regmap_config); |
| if (IS_ERR(rx8010->regs)) |
| return PTR_ERR(rx8010->regs); |
| |
| err = rx8010_init(dev); |
| if (err) |
| return err; |
| |
| rx8010->rtc = devm_rtc_allocate_device(dev); |
| if (IS_ERR(rx8010->rtc)) |
| return PTR_ERR(rx8010->rtc); |
| |
| if (client->irq > 0) { |
| unsigned long irqflags = IRQF_TRIGGER_LOW; |
| |
| if (dev_fwnode(&client->dev)) |
| irqflags = 0; |
| |
| err = devm_request_threaded_irq(dev, client->irq, NULL, |
| rx8010_irq_1_handler, |
| irqflags | IRQF_ONESHOT, |
| "rx8010", client); |
| if (err) { |
| dev_err(dev, "unable to request IRQ\n"); |
| return err; |
| } |
| } else { |
| clear_bit(RTC_FEATURE_ALARM, rx8010->rtc->features); |
| } |
| |
| rx8010->rtc->ops = &rx8010_rtc_ops; |
| rx8010->rtc->max_user_freq = 1; |
| rx8010->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; |
| rx8010->rtc->range_max = RTC_TIMESTAMP_END_2099; |
| |
| return devm_rtc_register_device(rx8010->rtc); |
| } |
| |
| static struct i2c_driver rx8010_driver = { |
| .driver = { |
| .name = "rtc-rx8010", |
| .of_match_table = of_match_ptr(rx8010_of_match), |
| }, |
| .probe = rx8010_probe, |
| .id_table = rx8010_id, |
| }; |
| |
| module_i2c_driver(rx8010_driver); |
| |
| MODULE_AUTHOR("Akshay Bhat <akshay.bhat@timesys.com>"); |
| MODULE_DESCRIPTION("Epson RX8010SJ RTC driver"); |
| MODULE_LICENSE("GPL v2"); |