diff options
Diffstat (limited to 'drivers/rtc/rtc-rx8010.c')
| -rw-r--r-- | drivers/rtc/rtc-rx8010.c | 435 |
1 files changed, 435 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-rx8010.c b/drivers/rtc/rtc-rx8010.c new file mode 100644 index 000000000..f44e212c0 --- /dev/null +++ b/drivers/rtc/rtc-rx8010.c @@ -0,0 +1,435 @@ +// 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"); |