diff options
Diffstat (limited to 'drivers/rtc/rtc-da9063.c')
| -rw-r--r-- | drivers/rtc/rtc-da9063.c | 333 |
1 files changed, 333 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-da9063.c b/drivers/rtc/rtc-da9063.c new file mode 100644 index 000000000000..595393098b09 --- /dev/null +++ b/drivers/rtc/rtc-da9063.c @@ -0,0 +1,333 @@ +/* rtc-da9063.c - Real time clock device driver for DA9063 + * Copyright (C) 2013-14 Dialog Semiconductor Ltd. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Library General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Library General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/interrupt.h> +#include <linux/rtc.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/regmap.h> +#include <linux/mfd/da9063/registers.h> +#include <linux/mfd/da9063/core.h> + +#define YEARS_TO_DA9063(year) ((year) - 100) +#define MONTHS_TO_DA9063(month) ((month) + 1) +#define YEARS_FROM_DA9063(year) ((year) + 100) +#define MONTHS_FROM_DA9063(month) ((month) - 1) + +#define RTC_DATA_LEN (DA9063_REG_COUNT_Y - DA9063_REG_COUNT_S + 1) +#define RTC_SEC 0 +#define RTC_MIN 1 +#define RTC_HOUR 2 +#define RTC_DAY 3 +#define RTC_MONTH 4 +#define RTC_YEAR 5 + +struct da9063_rtc { + struct rtc_device *rtc_dev; + struct da9063 *hw; + struct rtc_time alarm_time; + bool rtc_sync; +}; + +static void da9063_data_to_tm(u8 *data, struct rtc_time *tm) +{ + tm->tm_sec = data[RTC_SEC] & DA9063_COUNT_SEC_MASK; + tm->tm_min = data[RTC_MIN] & DA9063_COUNT_MIN_MASK; + tm->tm_hour = data[RTC_HOUR] & DA9063_COUNT_HOUR_MASK; + tm->tm_mday = data[RTC_DAY] & DA9063_COUNT_DAY_MASK; + tm->tm_mon = MONTHS_FROM_DA9063(data[RTC_MONTH] & + DA9063_COUNT_MONTH_MASK); + tm->tm_year = YEARS_FROM_DA9063(data[RTC_YEAR] & + DA9063_COUNT_YEAR_MASK); +} + +static void da9063_tm_to_data(struct rtc_time *tm, u8 *data) +{ + data[RTC_SEC] &= ~DA9063_COUNT_SEC_MASK; + data[RTC_SEC] |= tm->tm_sec & DA9063_COUNT_SEC_MASK; + + data[RTC_MIN] &= ~DA9063_COUNT_MIN_MASK; + data[RTC_MIN] |= tm->tm_min & DA9063_COUNT_MIN_MASK; + + data[RTC_HOUR] &= ~DA9063_COUNT_HOUR_MASK; + data[RTC_HOUR] |= tm->tm_hour & DA9063_COUNT_HOUR_MASK; + + data[RTC_DAY] &= ~DA9063_COUNT_DAY_MASK; + data[RTC_DAY] |= tm->tm_mday & DA9063_COUNT_DAY_MASK; + + data[RTC_MONTH] &= ~DA9063_COUNT_MONTH_MASK; + data[RTC_MONTH] |= MONTHS_TO_DA9063(tm->tm_mon) & + DA9063_COUNT_MONTH_MASK; + + data[RTC_YEAR] &= ~DA9063_COUNT_YEAR_MASK; + data[RTC_YEAR] |= YEARS_TO_DA9063(tm->tm_year) & + DA9063_COUNT_YEAR_MASK; +} + +static int da9063_rtc_stop_alarm(struct device *dev) +{ + struct da9063_rtc *rtc = dev_get_drvdata(dev); + + return regmap_update_bits(rtc->hw->regmap, DA9063_REG_ALARM_Y, + DA9063_ALARM_ON, 0); +} + +static int da9063_rtc_start_alarm(struct device *dev) +{ + struct da9063_rtc *rtc = dev_get_drvdata(dev); + + return regmap_update_bits(rtc->hw->regmap, DA9063_REG_ALARM_Y, + DA9063_ALARM_ON, DA9063_ALARM_ON); +} + +static int da9063_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct da9063_rtc *rtc = dev_get_drvdata(dev); + unsigned long tm_secs; + unsigned long al_secs; + u8 data[RTC_DATA_LEN]; + int ret; + + ret = regmap_bulk_read(rtc->hw->regmap, DA9063_REG_COUNT_S, + data, RTC_DATA_LEN); + if (ret < 0) { + dev_err(dev, "Failed to read RTC time data: %d\n", ret); + return ret; + } + + if (!(data[RTC_SEC] & DA9063_RTC_READ)) { + dev_dbg(dev, "RTC not yet ready to be read by the host\n"); + return -EINVAL; + } + + da9063_data_to_tm(data, tm); + + rtc_tm_to_time(tm, &tm_secs); + rtc_tm_to_time(&rtc->alarm_time, &al_secs); + + /* handle the rtc synchronisation delay */ + if (rtc->rtc_sync == true && al_secs - tm_secs == 1) + memcpy(tm, &rtc->alarm_time, sizeof(struct rtc_time)); + else + rtc->rtc_sync = false; + + return rtc_valid_tm(tm); +} + +static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct da9063_rtc *rtc = dev_get_drvdata(dev); + u8 data[RTC_DATA_LEN]; + int ret; + + da9063_tm_to_data(tm, data); + ret = regmap_bulk_write(rtc->hw->regmap, DA9063_REG_COUNT_S, + data, RTC_DATA_LEN); + if (ret < 0) + dev_err(dev, "Failed to set RTC time data: %d\n", ret); + + return ret; +} + +static int da9063_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct da9063_rtc *rtc = dev_get_drvdata(dev); + u8 data[RTC_DATA_LEN]; + int ret; + unsigned int val; + + ret = regmap_bulk_read(rtc->hw->regmap, DA9063_REG_ALARM_S, + &data[RTC_SEC], RTC_DATA_LEN); + if (ret < 0) + return ret; + + da9063_data_to_tm(data, &alrm->time); + + alrm->enabled = !!(data[RTC_YEAR] & DA9063_ALARM_ON); + + ret = regmap_read(rtc->hw->regmap, DA9063_REG_EVENT_A, &val); + if (ret < 0) + return ret; + + if (val & (DA9063_E_ALARM)) + alrm->pending = 1; + else + alrm->pending = 0; + + return 0; +} + +static int da9063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct da9063_rtc *rtc = dev_get_drvdata(dev); + u8 data[RTC_DATA_LEN]; + int ret; + + da9063_tm_to_data(&alrm->time, data); + + ret = da9063_rtc_stop_alarm(dev); + if (ret < 0) { + dev_err(dev, "Failed to stop alarm: %d\n", ret); + return ret; + } + + ret = regmap_bulk_write(rtc->hw->regmap, DA9063_REG_ALARM_S, + data, RTC_DATA_LEN); + if (ret < 0) { + dev_err(dev, "Failed to write alarm: %d\n", ret); + return ret; + } + + rtc->alarm_time = alrm->time; + + if (alrm->enabled) { + ret = da9063_rtc_start_alarm(dev); + if (ret < 0) { + dev_err(dev, "Failed to start alarm: %d\n", ret); + return ret; + } + } + + return ret; +} + +static int da9063_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + if (enabled) + return da9063_rtc_start_alarm(dev); + else + return da9063_rtc_stop_alarm(dev); +} + +static irqreturn_t da9063_alarm_event(int irq, void *data) +{ + struct da9063_rtc *rtc = data; + + regmap_update_bits(rtc->hw->regmap, DA9063_REG_ALARM_Y, + DA9063_ALARM_ON, 0); + + rtc->rtc_sync = true; + rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF); + + return IRQ_HANDLED; +} + +static const struct rtc_class_ops da9063_rtc_ops = { + .read_time = da9063_rtc_read_time, + .set_time = da9063_rtc_set_time, + .read_alarm = da9063_rtc_read_alarm, + .set_alarm = da9063_rtc_set_alarm, + .alarm_irq_enable = da9063_rtc_alarm_irq_enable, +}; + +static int da9063_rtc_probe(struct platform_device *pdev) +{ + struct da9063 *da9063 = dev_get_drvdata(pdev->dev.parent); + struct da9063_rtc *rtc; + int irq_alarm; + u8 data[RTC_DATA_LEN]; + int ret; + + ret = regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_E, + DA9063_RTC_EN, DA9063_RTC_EN); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to enable RTC\n"); + goto err; + } + + ret = regmap_update_bits(da9063->regmap, DA9063_REG_EN_32K, + DA9063_CRYSTAL, DA9063_CRYSTAL); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to run 32kHz oscillator\n"); + goto err; + } + + ret = regmap_update_bits(da9063->regmap, DA9063_REG_ALARM_S, + DA9063_ALARM_STATUS_TICK | DA9063_ALARM_STATUS_ALARM, + 0); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to access RTC alarm register\n"); + goto err; + } + + ret = regmap_update_bits(da9063->regmap, DA9063_REG_ALARM_S, + DA9063_ALARM_STATUS_ALARM, + DA9063_ALARM_STATUS_ALARM); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to access RTC alarm register\n"); + goto err; + } + + ret = regmap_update_bits(da9063->regmap, DA9063_REG_ALARM_Y, + DA9063_TICK_ON, 0); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to disable TICKs\n"); + goto err; + } + + ret = regmap_bulk_read(da9063->regmap, DA9063_REG_ALARM_S, + data, RTC_DATA_LEN); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to read initial alarm data: %d\n", + ret); + goto err; + } + + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); + if (!rtc) + return -ENOMEM; + + platform_set_drvdata(pdev, rtc); + + irq_alarm = platform_get_irq_byname(pdev, "ALARM"); + ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL, + da9063_alarm_event, + IRQF_TRIGGER_LOW | IRQF_ONESHOT, + "ALARM", rtc); + if (ret) { + dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n", + irq_alarm, ret); + goto err; + } + + rtc->hw = da9063; + rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, DA9063_DRVNAME_RTC, + &da9063_rtc_ops, THIS_MODULE); + if (IS_ERR(rtc->rtc_dev)) + return PTR_ERR(rtc->rtc_dev); + + da9063_data_to_tm(data, &rtc->alarm_time); + rtc->rtc_sync = false; +err: + return ret; +} + +static struct platform_driver da9063_rtc_driver = { + .probe = da9063_rtc_probe, + .driver = { + .name = DA9063_DRVNAME_RTC, + .owner = THIS_MODULE, + }, +}; + +module_platform_driver(da9063_rtc_driver); + +MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>"); +MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC); |