// SPDX-License-Identifier: GPL-2.0-or-later /* * Real time clock driver for DA9055 * * 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/mfd/da9055/core.h> #include <linux/mfd/da9055/reg.h> #include <linux/mfd/da9055/pdata.h> struct da9055_rtc { struct rtc_device *rtc; struct da9055 *da9055; int alarm_enable; }; static int da9055_rtc_enable_alarm(struct da9055_rtc *rtc, bool enable) { int ret; if (enable) { ret = da9055_reg_update(rtc->da9055, DA9055_REG_ALARM_Y, DA9055_RTC_ALM_EN, DA9055_RTC_ALM_EN); if (ret != 0) dev_err(rtc->da9055->dev, "Failed to enable ALM: %d\n", ret); rtc->alarm_enable = 1; } else { ret = da9055_reg_update(rtc->da9055, DA9055_REG_ALARM_Y, DA9055_RTC_ALM_EN, 0); if (ret != 0) dev_err(rtc->da9055->dev, "Failed to disable ALM: %d\n", ret); rtc->alarm_enable = 0; } return ret; } static irqreturn_t da9055_rtc_alm_irq(int irq, void *data) { struct da9055_rtc *rtc = data; da9055_rtc_enable_alarm(rtc, 0); rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); return IRQ_HANDLED; } static int da9055_read_alarm(struct da9055 *da9055, struct rtc_time *rtc_tm) { int ret; uint8_t v[5]; ret = da9055_group_read(da9055, DA9055_REG_ALARM_MI, 5, v); if (ret != 0) { dev_err(da9055->dev, "Failed to group read ALM: %d\n", ret); return ret; } rtc_tm->tm_year = (v[4] & DA9055_RTC_ALM_YEAR) + 100; rtc_tm->tm_mon = (v[3] & DA9055_RTC_ALM_MONTH) - 1; rtc_tm->tm_mday = v[2] & DA9055_RTC_ALM_DAY; rtc_tm->tm_hour = v[1] & DA9055_RTC_ALM_HOUR; rtc_tm->tm_min = v[0] & DA9055_RTC_ALM_MIN; rtc_tm->tm_sec = 0; return rtc_valid_tm(rtc_tm); } static int da9055_set_alarm(struct da9055 *da9055, struct rtc_time *rtc_tm) { int ret; uint8_t v[2]; rtc_tm->tm_year -= 100; rtc_tm->tm_mon += 1; ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MI, DA9055_RTC_ALM_MIN, rtc_tm->tm_min); if (ret != 0) { dev_err(da9055->dev, "Failed to write ALRM MIN: %d\n", ret); return ret; } v[0] = rtc_tm->tm_hour; v[1] = rtc_tm->tm_mday; ret = da9055_group_write(da9055, DA9055_REG_ALARM_H, 2, v); if (ret < 0) return ret; ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MO, DA9055_RTC_ALM_MONTH, rtc_tm->tm_mon); if (ret < 0) dev_err(da9055->dev, "Failed to write ALM Month:%d\n", ret); ret = da9055_reg_update(da9055, DA9055_REG_ALARM_Y, DA9055_RTC_ALM_YEAR, rtc_tm->tm_year); if (ret < 0) dev_err(da9055->dev, "Failed to write ALM Year:%d\n", ret); return ret; } static int da9055_rtc_get_alarm_status(struct da9055 *da9055) { int ret; ret = da9055_reg_read(da9055, DA9055_REG_ALARM_Y); if (ret < 0) { dev_err(da9055->dev, "Failed to read ALM: %d\n", ret); return ret; } ret &= DA9055_RTC_ALM_EN; return (ret > 0) ? 1 : 0; } static int da9055_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm) { struct da9055_rtc *rtc = dev_get_drvdata(dev); uint8_t v[6]; int ret; ret = da9055_reg_read(rtc->da9055, DA9055_REG_COUNT_S); if (ret < 0) return ret; /* * Registers are only valid when RTC_READ * status bit is asserted */ if (!(ret & DA9055_RTC_READ)) return -EBUSY; ret = da9055_group_read(rtc->da9055, DA9055_REG_COUNT_S, 6, v); if (ret < 0) { dev_err(rtc->da9055->dev, "Failed to read RTC time : %d\n", ret); return ret; } rtc_tm->tm_year = (v[5] & DA9055_RTC_YEAR) + 100; rtc_tm->tm_mon = (v[4] & DA9055_RTC_MONTH) - 1; rtc_tm->tm_mday = v[3] & DA9055_RTC_DAY; rtc_tm->tm_hour = v[2] & DA9055_RTC_HOUR; rtc_tm->tm_min = v[1] & DA9055_RTC_MIN; rtc_tm->tm_sec = v[0] & DA9055_RTC_SEC; return 0; } static int da9055_rtc_set_time(struct device *dev, struct rtc_time *tm) { struct da9055_rtc *rtc; uint8_t v[6]; 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; return da9055_group_write(rtc->da9055, DA9055_REG_COUNT_S, 6, v); } static int da9055_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) { int ret; struct rtc_time *tm = &alrm->time; struct da9055_rtc *rtc = dev_get_drvdata(dev); ret = da9055_read_alarm(rtc->da9055, tm); if (ret) return ret; alrm->enabled = da9055_rtc_get_alarm_status(rtc->da9055); return 0; } static int da9055_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) { int ret; struct rtc_time *tm = &alrm->time; struct da9055_rtc *rtc = dev_get_drvdata(dev); ret = da9055_rtc_enable_alarm(rtc, 0); if (ret < 0) return ret; ret = da9055_set_alarm(rtc->da9055, tm); if (ret) return ret; ret = da9055_rtc_enable_alarm(rtc, 1); return ret; } static int da9055_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct da9055_rtc *rtc = dev_get_drvdata(dev); return da9055_rtc_enable_alarm(rtc, enabled); } static const struct rtc_class_ops da9055_rtc_ops = { .read_time = da9055_rtc_read_time, .set_time = da9055_rtc_set_time, .read_alarm = da9055_rtc_read_alarm, .set_alarm = da9055_rtc_set_alarm, .alarm_irq_enable = da9055_rtc_alarm_irq_enable, }; static int da9055_rtc_device_init(struct da9055 *da9055, struct da9055_pdata *pdata) { int ret; /* Enable RTC and the internal Crystal */ ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, DA9055_RTC_EN, DA9055_RTC_EN); if (ret < 0) return ret; ret = da9055_reg_update(da9055, DA9055_REG_EN_32K, DA9055_CRYSTAL_EN, DA9055_CRYSTAL_EN); if (ret < 0) return ret; /* Enable RTC in Power Down mode */ ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, DA9055_RTC_MODE_PD, DA9055_RTC_MODE_PD); if (ret < 0) return ret; /* Enable RTC in Reset mode */ if (pdata && pdata->reset_enable) { ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, DA9055_RTC_MODE_SD, DA9055_RTC_MODE_SD << DA9055_RTC_MODE_SD_SHIFT); if (ret < 0) return ret; } /* Disable the RTC TICK ALM */ ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MO, DA9055_RTC_TICK_WAKE_MASK, 0); if (ret < 0) return ret; return 0; } static int da9055_rtc_probe(struct platform_device *pdev) { struct da9055_rtc *rtc; struct da9055_pdata *pdata = NULL; int ret, alm_irq; rtc = devm_kzalloc(&pdev->dev, sizeof(struct da9055_rtc), GFP_KERNEL); if (!rtc) return -ENOMEM; rtc->da9055 = dev_get_drvdata(pdev->dev.parent); pdata = dev_get_platdata(rtc->da9055->dev); platform_set_drvdata(pdev, rtc); ret = da9055_rtc_device_init(rtc->da9055, pdata); if (ret < 0) goto err_rtc; ret = da9055_reg_read(rtc->da9055, DA9055_REG_ALARM_Y); if (ret < 0) goto err_rtc; if (ret & DA9055_RTC_ALM_EN) rtc->alarm_enable = 1; device_init_wakeup(&pdev->dev, 1); rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &da9055_rtc_ops, THIS_MODULE); if (IS_ERR(rtc->rtc)) { ret = PTR_ERR(rtc->rtc); goto err_rtc; } alm_irq = platform_get_irq_byname(pdev, "ALM"); if (alm_irq < 0) return alm_irq; ret = devm_request_threaded_irq(&pdev->dev, alm_irq, NULL, da9055_rtc_alm_irq, IRQF_TRIGGER_HIGH | IRQF_ONESHOT, "ALM", rtc); if (ret != 0) dev_err(rtc->da9055->dev, "irq registration failed: %d\n", ret); err_rtc: return ret; } #ifdef CONFIG_PM /* Turn off the alarm if it should not be a wake source. */ static int da9055_rtc_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct da9055_rtc *rtc = dev_get_drvdata(&pdev->dev); int ret; if (!device_may_wakeup(&pdev->dev)) { /* Disable the ALM IRQ */ ret = da9055_rtc_enable_alarm(rtc, 0); if (ret < 0) dev_err(&pdev->dev, "Failed to disable RTC ALM\n"); } return 0; } /* Enable the alarm if it should be enabled (in case it was disabled to * prevent use as a wake source). */ static int da9055_rtc_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct da9055_rtc *rtc = dev_get_drvdata(&pdev->dev); int ret; if (!device_may_wakeup(&pdev->dev)) { if (rtc->alarm_enable) { ret = da9055_rtc_enable_alarm(rtc, 1); if (ret < 0) dev_err(&pdev->dev, "Failed to restart RTC ALM\n"); } } return 0; } /* Unconditionally disable the alarm */ static int da9055_rtc_freeze(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct da9055_rtc *rtc = dev_get_drvdata(&pdev->dev); int ret; ret = da9055_rtc_enable_alarm(rtc, 0); if (ret < 0) dev_err(&pdev->dev, "Failed to freeze RTC ALMs\n"); return 0; } #else #define da9055_rtc_suspend NULL #define da9055_rtc_resume NULL #define da9055_rtc_freeze NULL #endif static const struct dev_pm_ops da9055_rtc_pm_ops = { .suspend = da9055_rtc_suspend, .resume = da9055_rtc_resume, .freeze = da9055_rtc_freeze, .thaw = da9055_rtc_resume, .restore = da9055_rtc_resume, .poweroff = da9055_rtc_suspend, }; static struct platform_driver da9055_rtc_driver = { .probe = da9055_rtc_probe, .driver = { .name = "da9055-rtc", .pm = &da9055_rtc_pm_ops, }, }; module_platform_driver(da9055_rtc_driver); MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>"); MODULE_DESCRIPTION("RTC driver for Dialog DA9055 PMIC"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:da9055-rtc");