diff options
Diffstat (limited to 'drivers/rtc/rtc-da9052.c')
| -rw-r--r-- | drivers/rtc/rtc-da9052.c | 333 |
1 files changed, 333 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-da9052.c b/drivers/rtc/rtc-da9052.c new file mode 100644 index 000000000..58de10da3 --- /dev/null +++ b/drivers/rtc/rtc-da9052.c @@ -0,0 +1,333 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Real time clock driver for DA9052 + * + * Copyright(c) 2012 Dialog Semiconductor Ltd. + * + * Author: Dajun Dajun Chen <dajun.chen@diasemi.com> + */ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/rtc.h> +#include <linux/err.h> +#include <linux/delay.h> + +#include <linux/mfd/da9052/da9052.h> +#include <linux/mfd/da9052/reg.h> + +#define rtc_err(rtc, fmt, ...) \ + dev_err(rtc->da9052->dev, "%s: " fmt, __func__, ##__VA_ARGS__) + +#define DA9052_GET_TIME_RETRIES 5 + +struct da9052_rtc { + struct rtc_device *rtc; + struct da9052 *da9052; +}; + +static int da9052_rtc_enable_alarm(struct da9052_rtc *rtc, bool enable) +{ + int ret; + if (enable) { + ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG, + DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON, + DA9052_ALARM_Y_ALARM_ON); + if (ret != 0) + rtc_err(rtc, "Failed to enable ALM: %d\n", ret); + } else { + ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG, + DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON, 0); + if (ret != 0) + rtc_err(rtc, "Write error: %d\n", ret); + } + return ret; +} + +static irqreturn_t da9052_rtc_irq(int irq, void *data) +{ + struct da9052_rtc *rtc = data; + + rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); + + return IRQ_HANDLED; +} + +static int da9052_read_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm) +{ + int ret; + uint8_t v[2][5]; + int idx = 1; + int timeout = DA9052_GET_TIME_RETRIES; + + ret = da9052_group_read(rtc->da9052, DA9052_ALARM_MI_REG, 5, &v[0][0]); + if (ret) { + rtc_err(rtc, "Failed to group read ALM: %d\n", ret); + return ret; + } + + do { + ret = da9052_group_read(rtc->da9052, + DA9052_ALARM_MI_REG, 5, &v[idx][0]); + if (ret) { + rtc_err(rtc, "Failed to group read ALM: %d\n", ret); + return ret; + } + + if (memcmp(&v[0][0], &v[1][0], 5) == 0) { + rtc_tm->tm_year = (v[0][4] & DA9052_RTC_YEAR) + 100; + rtc_tm->tm_mon = (v[0][3] & DA9052_RTC_MONTH) - 1; + rtc_tm->tm_mday = v[0][2] & DA9052_RTC_DAY; + rtc_tm->tm_hour = v[0][1] & DA9052_RTC_HOUR; + rtc_tm->tm_min = v[0][0] & DA9052_RTC_MIN; + rtc_tm->tm_sec = 0; + + ret = rtc_valid_tm(rtc_tm); + return ret; + } + + idx = (1-idx); + msleep(20); + + } while (timeout--); + + rtc_err(rtc, "Timed out reading alarm time\n"); + + return -EIO; +} + +static int da9052_set_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm) +{ + struct da9052 *da9052 = rtc->da9052; + unsigned long alm_time; + int ret; + uint8_t v[3]; + + alm_time = rtc_tm_to_time64(rtc_tm); + + if (rtc_tm->tm_sec > 0) { + alm_time += 60 - rtc_tm->tm_sec; + rtc_time64_to_tm(alm_time, rtc_tm); + } + BUG_ON(rtc_tm->tm_sec); /* it will cause repeated irqs if not zero */ + + rtc_tm->tm_year -= 100; + rtc_tm->tm_mon += 1; + + ret = da9052_reg_update(da9052, DA9052_ALARM_MI_REG, + DA9052_RTC_MIN, rtc_tm->tm_min); + if (ret != 0) { + rtc_err(rtc, "Failed to write ALRM MIN: %d\n", ret); + return ret; + } + + v[0] = rtc_tm->tm_hour; + v[1] = rtc_tm->tm_mday; + v[2] = rtc_tm->tm_mon; + + ret = da9052_group_write(da9052, DA9052_ALARM_H_REG, 3, v); + if (ret < 0) + return ret; + + ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG, + DA9052_RTC_YEAR, rtc_tm->tm_year); + if (ret != 0) + rtc_err(rtc, "Failed to write ALRM YEAR: %d\n", ret); + + return ret; +} + +static int da9052_rtc_get_alarm_status(struct da9052_rtc *rtc) +{ + int ret; + + ret = da9052_reg_read(rtc->da9052, DA9052_ALARM_Y_REG); + if (ret < 0) { + rtc_err(rtc, "Failed to read ALM: %d\n", ret); + return ret; + } + + return !!(ret&DA9052_ALARM_Y_ALARM_ON); +} + +static int da9052_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm) +{ + struct da9052_rtc *rtc = dev_get_drvdata(dev); + int ret; + uint8_t v[2][6]; + int idx = 1; + int timeout = DA9052_GET_TIME_RETRIES; + + ret = da9052_group_read(rtc->da9052, DA9052_COUNT_S_REG, 6, &v[0][0]); + if (ret) { + rtc_err(rtc, "Failed to read RTC time : %d\n", ret); + return ret; + } + + do { + ret = da9052_group_read(rtc->da9052, + DA9052_COUNT_S_REG, 6, &v[idx][0]); + if (ret) { + rtc_err(rtc, "Failed to read RTC time : %d\n", ret); + return ret; + } + + if (memcmp(&v[0][0], &v[1][0], 6) == 0) { + rtc_tm->tm_year = (v[0][5] & DA9052_RTC_YEAR) + 100; + rtc_tm->tm_mon = (v[0][4] & DA9052_RTC_MONTH) - 1; + rtc_tm->tm_mday = v[0][3] & DA9052_RTC_DAY; + rtc_tm->tm_hour = v[0][2] & DA9052_RTC_HOUR; + rtc_tm->tm_min = v[0][1] & DA9052_RTC_MIN; + rtc_tm->tm_sec = v[0][0] & DA9052_RTC_SEC; + + return 0; + } + + idx = (1-idx); + msleep(20); + + } while (timeout--); + + rtc_err(rtc, "Timed out reading time\n"); + + return -EIO; +} + +static int da9052_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct da9052_rtc *rtc; + uint8_t v[6]; + int ret; + + /* DA9052 only has 6 bits for year - to represent 2000-2063 */ + if ((tm->tm_year < 100) || (tm->tm_year > 163)) + return -EINVAL; + + rtc = dev_get_drvdata(dev); + + v[0] = tm->tm_sec; + v[1] = tm->tm_min; + v[2] = tm->tm_hour; + v[3] = tm->tm_mday; + v[4] = tm->tm_mon + 1; + v[5] = tm->tm_year - 100; + + ret = da9052_group_write(rtc->da9052, DA9052_COUNT_S_REG, 6, v); + if (ret < 0) + rtc_err(rtc, "failed to set RTC time: %d\n", ret); + return ret; +} + +static int da9052_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + int ret; + struct rtc_time *tm = &alrm->time; + struct da9052_rtc *rtc = dev_get_drvdata(dev); + + ret = da9052_read_alarm(rtc, tm); + if (ret < 0) { + rtc_err(rtc, "failed to read RTC alarm: %d\n", ret); + return ret; + } + + alrm->enabled = da9052_rtc_get_alarm_status(rtc); + return 0; +} + +static int da9052_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + int ret; + struct rtc_time *tm = &alrm->time; + struct da9052_rtc *rtc = dev_get_drvdata(dev); + + /* DA9052 only has 6 bits for year - to represent 2000-2063 */ + if ((tm->tm_year < 100) || (tm->tm_year > 163)) + return -EINVAL; + + ret = da9052_rtc_enable_alarm(rtc, 0); + if (ret < 0) + return ret; + + ret = da9052_set_alarm(rtc, tm); + if (ret < 0) + return ret; + + ret = da9052_rtc_enable_alarm(rtc, 1); + return ret; +} + +static int da9052_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + struct da9052_rtc *rtc = dev_get_drvdata(dev); + + return da9052_rtc_enable_alarm(rtc, enabled); +} + +static const struct rtc_class_ops da9052_rtc_ops = { + .read_time = da9052_rtc_read_time, + .set_time = da9052_rtc_set_time, + .read_alarm = da9052_rtc_read_alarm, + .set_alarm = da9052_rtc_set_alarm, + .alarm_irq_enable = da9052_rtc_alarm_irq_enable, +}; + +static int da9052_rtc_probe(struct platform_device *pdev) +{ + struct da9052_rtc *rtc; + int ret; + + rtc = devm_kzalloc(&pdev->dev, sizeof(struct da9052_rtc), GFP_KERNEL); + if (!rtc) + return -ENOMEM; + + rtc->da9052 = dev_get_drvdata(pdev->dev.parent); + platform_set_drvdata(pdev, rtc); + + ret = da9052_reg_write(rtc->da9052, DA9052_BBAT_CONT_REG, 0xFE); + if (ret < 0) { + rtc_err(rtc, + "Failed to setup RTC battery charging: %d\n", ret); + return ret; + } + + ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG, + DA9052_ALARM_Y_TICK_ON, 0); + if (ret != 0) + rtc_err(rtc, "Failed to disable TICKS: %d\n", ret); + + device_init_wakeup(&pdev->dev, true); + rtc->rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtc->rtc)) + return PTR_ERR(rtc->rtc); + + rtc->rtc->ops = &da9052_rtc_ops; + rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; + rtc->rtc->range_max = RTC_TIMESTAMP_END_2063; + + ret = rtc_register_device(rtc->rtc); + if (ret) + return ret; + + ret = da9052_request_irq(rtc->da9052, DA9052_IRQ_ALARM, "ALM", + da9052_rtc_irq, rtc); + if (ret != 0) { + rtc_err(rtc, "irq registration failed: %d\n", ret); + return ret; + } + + return 0; +} + +static struct platform_driver da9052_rtc_driver = { + .probe = da9052_rtc_probe, + .driver = { + .name = "da9052-rtc", + }, +}; + +module_platform_driver(da9052_rtc_driver); + +MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>"); +MODULE_DESCRIPTION("RTC driver for Dialog DA9052 PMIC"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:da9052-rtc"); |