M7350/kernel/drivers/rtc/rtc-da9063.c
2024-09-09 08:57:42 +00:00

354 lines
9.1 KiB
C

/* rtc-da9063.c - Real time clock device driver for DA9063
* Copyright (C) 2013-14 Dialog Semiconductor Ltd.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/rtc.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/regmap.h>
#include <linux/mfd/da9063/registers.h>
#include <linux/mfd/da9063/core.h>
#define YEARS_TO_DA9063(year) ((year) - 100)
#define MONTHS_TO_DA9063(month) ((month) + 1)
#define YEARS_FROM_DA9063(year) ((year) + 100)
#define MONTHS_FROM_DA9063(month) ((month) - 1)
#define RTC_ALARM_DATA_LEN (DA9063_AD_REG_ALARM_Y - DA9063_AD_REG_ALARM_MI + 1)
#define RTC_DATA_LEN (DA9063_REG_COUNT_Y - DA9063_REG_COUNT_S + 1)
#define RTC_SEC 0
#define RTC_MIN 1
#define RTC_HOUR 2
#define RTC_DAY 3
#define RTC_MONTH 4
#define RTC_YEAR 5
struct da9063_rtc {
struct rtc_device *rtc_dev;
struct da9063 *hw;
struct rtc_time alarm_time;
bool rtc_sync;
int alarm_year;
int alarm_start;
int alarm_len;
int data_start;
};
static void da9063_data_to_tm(u8 *data, struct rtc_time *tm)
{
tm->tm_sec = data[RTC_SEC] & DA9063_COUNT_SEC_MASK;
tm->tm_min = data[RTC_MIN] & DA9063_COUNT_MIN_MASK;
tm->tm_hour = data[RTC_HOUR] & DA9063_COUNT_HOUR_MASK;
tm->tm_mday = data[RTC_DAY] & DA9063_COUNT_DAY_MASK;
tm->tm_mon = MONTHS_FROM_DA9063(data[RTC_MONTH] &
DA9063_COUNT_MONTH_MASK);
tm->tm_year = YEARS_FROM_DA9063(data[RTC_YEAR] &
DA9063_COUNT_YEAR_MASK);
}
static void da9063_tm_to_data(struct rtc_time *tm, u8 *data)
{
data[RTC_SEC] &= ~DA9063_COUNT_SEC_MASK;
data[RTC_SEC] |= tm->tm_sec & DA9063_COUNT_SEC_MASK;
data[RTC_MIN] &= ~DA9063_COUNT_MIN_MASK;
data[RTC_MIN] |= tm->tm_min & DA9063_COUNT_MIN_MASK;
data[RTC_HOUR] &= ~DA9063_COUNT_HOUR_MASK;
data[RTC_HOUR] |= tm->tm_hour & DA9063_COUNT_HOUR_MASK;
data[RTC_DAY] &= ~DA9063_COUNT_DAY_MASK;
data[RTC_DAY] |= tm->tm_mday & DA9063_COUNT_DAY_MASK;
data[RTC_MONTH] &= ~DA9063_COUNT_MONTH_MASK;
data[RTC_MONTH] |= MONTHS_TO_DA9063(tm->tm_mon) &
DA9063_COUNT_MONTH_MASK;
data[RTC_YEAR] &= ~DA9063_COUNT_YEAR_MASK;
data[RTC_YEAR] |= YEARS_TO_DA9063(tm->tm_year) &
DA9063_COUNT_YEAR_MASK;
}
static int da9063_rtc_stop_alarm(struct device *dev)
{
struct da9063_rtc *rtc = dev_get_drvdata(dev);
return regmap_update_bits(rtc->hw->regmap, rtc->alarm_year,
DA9063_ALARM_ON, 0);
}
static int da9063_rtc_start_alarm(struct device *dev)
{
struct da9063_rtc *rtc = dev_get_drvdata(dev);
return regmap_update_bits(rtc->hw->regmap, rtc->alarm_year,
DA9063_ALARM_ON, DA9063_ALARM_ON);
}
static int da9063_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct da9063_rtc *rtc = dev_get_drvdata(dev);
unsigned long tm_secs;
unsigned long al_secs;
u8 data[RTC_DATA_LEN];
int ret;
ret = regmap_bulk_read(rtc->hw->regmap, DA9063_REG_COUNT_S,
data, RTC_DATA_LEN);
if (ret < 0) {
dev_err(dev, "Failed to read RTC time data: %d\n", ret);
return ret;
}
if (!(data[RTC_SEC] & DA9063_RTC_READ)) {
dev_dbg(dev, "RTC not yet ready to be read by the host\n");
return -EINVAL;
}
da9063_data_to_tm(data, tm);
rtc_tm_to_time(tm, &tm_secs);
rtc_tm_to_time(&rtc->alarm_time, &al_secs);
/* handle the rtc synchronisation delay */
if (rtc->rtc_sync == true && al_secs - tm_secs == 1)
memcpy(tm, &rtc->alarm_time, sizeof(struct rtc_time));
else
rtc->rtc_sync = false;
return rtc_valid_tm(tm);
}
static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct da9063_rtc *rtc = dev_get_drvdata(dev);
u8 data[RTC_DATA_LEN];
int ret;
da9063_tm_to_data(tm, data);
ret = regmap_bulk_write(rtc->hw->regmap, DA9063_REG_COUNT_S,
data, RTC_DATA_LEN);
if (ret < 0)
dev_err(dev, "Failed to set RTC time data: %d\n", ret);
return ret;
}
static int da9063_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct da9063_rtc *rtc = dev_get_drvdata(dev);
u8 data[RTC_DATA_LEN];
int ret;
unsigned int val;
data[RTC_SEC] = 0;
ret = regmap_bulk_read(rtc->hw->regmap, rtc->alarm_start,
&data[rtc->data_start], rtc->alarm_len);
if (ret < 0)
return ret;
da9063_data_to_tm(data, &alrm->time);
alrm->enabled = !!(data[RTC_YEAR] & DA9063_ALARM_ON);
ret = regmap_read(rtc->hw->regmap, DA9063_REG_EVENT_A, &val);
if (ret < 0)
return ret;
if (val & (DA9063_E_ALARM))
alrm->pending = 1;
else
alrm->pending = 0;
return 0;
}
static int da9063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct da9063_rtc *rtc = dev_get_drvdata(dev);
u8 data[RTC_DATA_LEN];
int ret;
da9063_tm_to_data(&alrm->time, data);
ret = da9063_rtc_stop_alarm(dev);
if (ret < 0) {
dev_err(dev, "Failed to stop alarm: %d\n", ret);
return ret;
}
ret = regmap_bulk_write(rtc->hw->regmap, rtc->alarm_start,
&data[rtc->data_start], rtc->alarm_len);
if (ret < 0) {
dev_err(dev, "Failed to write alarm: %d\n", ret);
return ret;
}
da9063_data_to_tm(data, &rtc->alarm_time);
if (alrm->enabled) {
ret = da9063_rtc_start_alarm(dev);
if (ret < 0) {
dev_err(dev, "Failed to start alarm: %d\n", ret);
return ret;
}
}
return ret;
}
static int da9063_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
if (enabled)
return da9063_rtc_start_alarm(dev);
else
return da9063_rtc_stop_alarm(dev);
}
static irqreturn_t da9063_alarm_event(int irq, void *data)
{
struct da9063_rtc *rtc = data;
regmap_update_bits(rtc->hw->regmap, rtc->alarm_year,
DA9063_ALARM_ON, 0);
rtc->rtc_sync = true;
rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF);
return IRQ_HANDLED;
}
static const struct rtc_class_ops da9063_rtc_ops = {
.read_time = da9063_rtc_read_time,
.set_time = da9063_rtc_set_time,
.read_alarm = da9063_rtc_read_alarm,
.set_alarm = da9063_rtc_set_alarm,
.alarm_irq_enable = da9063_rtc_alarm_irq_enable,
};
static int da9063_rtc_probe(struct platform_device *pdev)
{
struct da9063 *da9063 = dev_get_drvdata(pdev->dev.parent);
struct da9063_rtc *rtc;
int irq_alarm;
u8 data[RTC_DATA_LEN];
int ret;
ret = regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_E,
DA9063_RTC_EN, DA9063_RTC_EN);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to enable RTC\n");
goto err;
}
ret = regmap_update_bits(da9063->regmap, DA9063_REG_EN_32K,
DA9063_CRYSTAL, DA9063_CRYSTAL);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to run 32kHz oscillator\n");
goto err;
}
rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
if (!rtc)
return -ENOMEM;
if (da9063->variant_code == PMIC_DA9063_AD) {
rtc->alarm_year = DA9063_AD_REG_ALARM_Y;
rtc->alarm_start = DA9063_AD_REG_ALARM_MI;
rtc->alarm_len = RTC_ALARM_DATA_LEN;
rtc->data_start = RTC_MIN;
} else {
rtc->alarm_year = DA9063_BB_REG_ALARM_Y;
rtc->alarm_start = DA9063_BB_REG_ALARM_S;
rtc->alarm_len = RTC_DATA_LEN;
rtc->data_start = RTC_SEC;
}
ret = regmap_update_bits(da9063->regmap, rtc->alarm_start,
DA9063_ALARM_STATUS_TICK | DA9063_ALARM_STATUS_ALARM,
0);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
goto err;
}
ret = regmap_update_bits(da9063->regmap, rtc->alarm_start,
DA9063_ALARM_STATUS_ALARM,
DA9063_ALARM_STATUS_ALARM);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
goto err;
}
ret = regmap_update_bits(da9063->regmap, rtc->alarm_year,
DA9063_TICK_ON, 0);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to disable TICKs\n");
goto err;
}
data[RTC_SEC] = 0;
ret = regmap_bulk_read(da9063->regmap, rtc->alarm_start,
&data[rtc->data_start], rtc->alarm_len);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to read initial alarm data: %d\n",
ret);
goto err;
}
platform_set_drvdata(pdev, rtc);
irq_alarm = platform_get_irq_byname(pdev, "ALARM");
ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL,
da9063_alarm_event,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
"ALARM", rtc);
if (ret) {
dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n",
irq_alarm, ret);
goto err;
}
rtc->hw = da9063;
rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, DA9063_DRVNAME_RTC,
&da9063_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc->rtc_dev))
return PTR_ERR(rtc->rtc_dev);
da9063_data_to_tm(data, &rtc->alarm_time);
rtc->rtc_sync = false;
err:
return ret;
}
static struct platform_driver da9063_rtc_driver = {
.probe = da9063_rtc_probe,
.driver = {
.name = DA9063_DRVNAME_RTC,
.owner = THIS_MODULE,
},
};
module_platform_driver(da9063_rtc_driver);
MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC);