// 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");