linux/drivers/rtc/rtc-da9055.c

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/*
* 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;
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 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",
.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");