diff options
Diffstat (limited to 'drivers/rtc/rtc-da9055.c')
| -rw-r--r-- | drivers/rtc/rtc-da9055.c | 404 | 
1 files changed, 404 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-da9055.c b/drivers/rtc/rtc-da9055.c new file mode 100644 index 00000000000..a825491331c --- /dev/null +++ b/drivers/rtc/rtc-da9055.c @@ -0,0 +1,404 @@ +/* + * Real time clock driver for DA9055 + * + * Copyright(c) 2012 Dialog Semiconductor Ltd. + * + * Author: Dajun Dajun Chen <dajun.chen@diasemi.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + */ + +#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; + +	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 rtc_valid_tm(rtc_tm); +} + +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", +		.owner  = THIS_MODULE, +		.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");  | 
