linux/drivers/rtc/rtc-mt6397.c
Javier Martinez Canillas 582841a4f6 rtc: mt6397: Remove plaform module alias
The driver uses the MODULE_ALIAS() macro to export a platform module alias
to allow the module to be autoloaded if the device is registered using the
legacy platform registration mechanism but the driver is always used by OF
only machines so the alias is not needed and should just be removed.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-03-14 17:08:26 +01:00

422 lines
10 KiB
C

/*
* Copyright (c) 2014-2015 MediaTek Inc.
* Author: Tianping.Fang <tianping.fang@mediatek.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program 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 General Public License for more details.
*/
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/rtc.h>
#include <linux/irqdomain.h>
#include <linux/platform_device.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/io.h>
#include <linux/mfd/mt6397/core.h>
#define RTC_BBPU 0x0000
#define RTC_BBPU_CBUSY BIT(6)
#define RTC_WRTGR 0x003c
#define RTC_IRQ_STA 0x0002
#define RTC_IRQ_STA_AL BIT(0)
#define RTC_IRQ_STA_LP BIT(3)
#define RTC_IRQ_EN 0x0004
#define RTC_IRQ_EN_AL BIT(0)
#define RTC_IRQ_EN_ONESHOT BIT(2)
#define RTC_IRQ_EN_LP BIT(3)
#define RTC_IRQ_EN_ONESHOT_AL (RTC_IRQ_EN_ONESHOT | RTC_IRQ_EN_AL)
#define RTC_AL_MASK 0x0008
#define RTC_AL_MASK_DOW BIT(4)
#define RTC_TC_SEC 0x000a
/* Min, Hour, Dom... register offset to RTC_TC_SEC */
#define RTC_OFFSET_SEC 0
#define RTC_OFFSET_MIN 1
#define RTC_OFFSET_HOUR 2
#define RTC_OFFSET_DOM 3
#define RTC_OFFSET_DOW 4
#define RTC_OFFSET_MTH 5
#define RTC_OFFSET_YEAR 6
#define RTC_OFFSET_COUNT 7
#define RTC_AL_SEC 0x0018
#define RTC_PDN2 0x002e
#define RTC_PDN2_PWRON_ALARM BIT(4)
#define RTC_MIN_YEAR 1968
#define RTC_BASE_YEAR 1900
#define RTC_NUM_YEARS 128
#define RTC_MIN_YEAR_OFFSET (RTC_MIN_YEAR - RTC_BASE_YEAR)
struct mt6397_rtc {
struct device *dev;
struct rtc_device *rtc_dev;
struct mutex lock;
struct regmap *regmap;
int irq;
u32 addr_base;
};
static int mtk_rtc_write_trigger(struct mt6397_rtc *rtc)
{
unsigned long timeout = jiffies + HZ;
int ret;
u32 data;
ret = regmap_write(rtc->regmap, rtc->addr_base + RTC_WRTGR, 1);
if (ret < 0)
return ret;
while (1) {
ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_BBPU,
&data);
if (ret < 0)
break;
if (!(data & RTC_BBPU_CBUSY))
break;
if (time_after(jiffies, timeout)) {
ret = -ETIMEDOUT;
break;
}
cpu_relax();
}
return ret;
}
static irqreturn_t mtk_rtc_irq_handler_thread(int irq, void *data)
{
struct mt6397_rtc *rtc = data;
u32 irqsta, irqen;
int ret;
ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_IRQ_STA, &irqsta);
if ((ret >= 0) && (irqsta & RTC_IRQ_STA_AL)) {
rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF);
irqen = irqsta & ~RTC_IRQ_EN_AL;
mutex_lock(&rtc->lock);
if (regmap_write(rtc->regmap, rtc->addr_base + RTC_IRQ_EN,
irqen) < 0)
mtk_rtc_write_trigger(rtc);
mutex_unlock(&rtc->lock);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
static int __mtk_rtc_read_time(struct mt6397_rtc *rtc,
struct rtc_time *tm, int *sec)
{
int ret;
u16 data[RTC_OFFSET_COUNT];
mutex_lock(&rtc->lock);
ret = regmap_bulk_read(rtc->regmap, rtc->addr_base + RTC_TC_SEC,
data, RTC_OFFSET_COUNT);
if (ret < 0)
goto exit;
tm->tm_sec = data[RTC_OFFSET_SEC];
tm->tm_min = data[RTC_OFFSET_MIN];
tm->tm_hour = data[RTC_OFFSET_HOUR];
tm->tm_mday = data[RTC_OFFSET_DOM];
tm->tm_mon = data[RTC_OFFSET_MTH];
tm->tm_year = data[RTC_OFFSET_YEAR];
ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_TC_SEC, sec);
exit:
mutex_unlock(&rtc->lock);
return ret;
}
static int mtk_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
time64_t time;
struct mt6397_rtc *rtc = dev_get_drvdata(dev);
int days, sec, ret;
do {
ret = __mtk_rtc_read_time(rtc, tm, &sec);
if (ret < 0)
goto exit;
} while (sec < tm->tm_sec);
/* HW register use 7 bits to store year data, minus
* RTC_MIN_YEAR_OFFSET before write year data to register, and plus
* RTC_MIN_YEAR_OFFSET back after read year from register
*/
tm->tm_year += RTC_MIN_YEAR_OFFSET;
/* HW register start mon from one, but tm_mon start from zero. */
tm->tm_mon--;
time = rtc_tm_to_time64(tm);
/* rtc_tm_to_time64 covert Gregorian date to seconds since
* 01-01-1970 00:00:00, and this date is Thursday.
*/
days = div_s64(time, 86400);
tm->tm_wday = (days + 4) % 7;
exit:
return ret;
}
static int mtk_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct mt6397_rtc *rtc = dev_get_drvdata(dev);
int ret;
u16 data[RTC_OFFSET_COUNT];
tm->tm_year -= RTC_MIN_YEAR_OFFSET;
tm->tm_mon++;
data[RTC_OFFSET_SEC] = tm->tm_sec;
data[RTC_OFFSET_MIN] = tm->tm_min;
data[RTC_OFFSET_HOUR] = tm->tm_hour;
data[RTC_OFFSET_DOM] = tm->tm_mday;
data[RTC_OFFSET_MTH] = tm->tm_mon;
data[RTC_OFFSET_YEAR] = tm->tm_year;
mutex_lock(&rtc->lock);
ret = regmap_bulk_write(rtc->regmap, rtc->addr_base + RTC_TC_SEC,
data, RTC_OFFSET_COUNT);
if (ret < 0)
goto exit;
/* Time register write to hardware after call trigger function */
ret = mtk_rtc_write_trigger(rtc);
exit:
mutex_unlock(&rtc->lock);
return ret;
}
static int mtk_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
struct rtc_time *tm = &alm->time;
struct mt6397_rtc *rtc = dev_get_drvdata(dev);
u32 irqen, pdn2;
int ret;
u16 data[RTC_OFFSET_COUNT];
mutex_lock(&rtc->lock);
ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_IRQ_EN, &irqen);
if (ret < 0)
goto err_exit;
ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_PDN2, &pdn2);
if (ret < 0)
goto err_exit;
ret = regmap_bulk_read(rtc->regmap, rtc->addr_base + RTC_AL_SEC,
data, RTC_OFFSET_COUNT);
if (ret < 0)
goto err_exit;
alm->enabled = !!(irqen & RTC_IRQ_EN_AL);
alm->pending = !!(pdn2 & RTC_PDN2_PWRON_ALARM);
mutex_unlock(&rtc->lock);
tm->tm_sec = data[RTC_OFFSET_SEC];
tm->tm_min = data[RTC_OFFSET_MIN];
tm->tm_hour = data[RTC_OFFSET_HOUR];
tm->tm_mday = data[RTC_OFFSET_DOM];
tm->tm_mon = data[RTC_OFFSET_MTH];
tm->tm_year = data[RTC_OFFSET_YEAR];
tm->tm_year += RTC_MIN_YEAR_OFFSET;
tm->tm_mon--;
return 0;
err_exit:
mutex_unlock(&rtc->lock);
return ret;
}
static int mtk_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
struct rtc_time *tm = &alm->time;
struct mt6397_rtc *rtc = dev_get_drvdata(dev);
int ret;
u16 data[RTC_OFFSET_COUNT];
tm->tm_year -= RTC_MIN_YEAR_OFFSET;
tm->tm_mon++;
data[RTC_OFFSET_SEC] = tm->tm_sec;
data[RTC_OFFSET_MIN] = tm->tm_min;
data[RTC_OFFSET_HOUR] = tm->tm_hour;
data[RTC_OFFSET_DOM] = tm->tm_mday;
data[RTC_OFFSET_MTH] = tm->tm_mon;
data[RTC_OFFSET_YEAR] = tm->tm_year;
mutex_lock(&rtc->lock);
if (alm->enabled) {
ret = regmap_bulk_write(rtc->regmap,
rtc->addr_base + RTC_AL_SEC,
data, RTC_OFFSET_COUNT);
if (ret < 0)
goto exit;
ret = regmap_write(rtc->regmap, rtc->addr_base + RTC_AL_MASK,
RTC_AL_MASK_DOW);
if (ret < 0)
goto exit;
ret = regmap_update_bits(rtc->regmap,
rtc->addr_base + RTC_IRQ_EN,
RTC_IRQ_EN_ONESHOT_AL,
RTC_IRQ_EN_ONESHOT_AL);
if (ret < 0)
goto exit;
} else {
ret = regmap_update_bits(rtc->regmap,
rtc->addr_base + RTC_IRQ_EN,
RTC_IRQ_EN_ONESHOT_AL, 0);
if (ret < 0)
goto exit;
}
/* All alarm time register write to hardware after calling
* mtk_rtc_write_trigger. This can avoid race condition if alarm
* occur happen during writing alarm time register.
*/
ret = mtk_rtc_write_trigger(rtc);
exit:
mutex_unlock(&rtc->lock);
return ret;
}
static struct rtc_class_ops mtk_rtc_ops = {
.read_time = mtk_rtc_read_time,
.set_time = mtk_rtc_set_time,
.read_alarm = mtk_rtc_read_alarm,
.set_alarm = mtk_rtc_set_alarm,
};
static int mtk_rtc_probe(struct platform_device *pdev)
{
struct resource *res;
struct mt6397_chip *mt6397_chip = dev_get_drvdata(pdev->dev.parent);
struct mt6397_rtc *rtc;
int ret;
rtc = devm_kzalloc(&pdev->dev, sizeof(struct mt6397_rtc), GFP_KERNEL);
if (!rtc)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
rtc->addr_base = res->start;
res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
rtc->irq = irq_create_mapping(mt6397_chip->irq_domain, res->start);
if (rtc->irq <= 0)
return -EINVAL;
rtc->regmap = mt6397_chip->regmap;
rtc->dev = &pdev->dev;
mutex_init(&rtc->lock);
platform_set_drvdata(pdev, rtc);
ret = request_threaded_irq(rtc->irq, NULL,
mtk_rtc_irq_handler_thread,
IRQF_ONESHOT | IRQF_TRIGGER_HIGH,
"mt6397-rtc", rtc);
if (ret) {
dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
rtc->irq, ret);
goto out_dispose_irq;
}
device_init_wakeup(&pdev->dev, 1);
rtc->rtc_dev = rtc_device_register("mt6397-rtc", &pdev->dev,
&mtk_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc->rtc_dev)) {
dev_err(&pdev->dev, "register rtc device failed\n");
ret = PTR_ERR(rtc->rtc_dev);
goto out_free_irq;
}
return 0;
out_free_irq:
free_irq(rtc->irq, rtc->rtc_dev);
out_dispose_irq:
irq_dispose_mapping(rtc->irq);
return ret;
}
static int mtk_rtc_remove(struct platform_device *pdev)
{
struct mt6397_rtc *rtc = platform_get_drvdata(pdev);
rtc_device_unregister(rtc->rtc_dev);
free_irq(rtc->irq, rtc->rtc_dev);
irq_dispose_mapping(rtc->irq);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int mt6397_rtc_suspend(struct device *dev)
{
struct mt6397_rtc *rtc = dev_get_drvdata(dev);
if (device_may_wakeup(dev))
enable_irq_wake(rtc->irq);
return 0;
}
static int mt6397_rtc_resume(struct device *dev)
{
struct mt6397_rtc *rtc = dev_get_drvdata(dev);
if (device_may_wakeup(dev))
disable_irq_wake(rtc->irq);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(mt6397_pm_ops, mt6397_rtc_suspend,
mt6397_rtc_resume);
static const struct of_device_id mt6397_rtc_of_match[] = {
{ .compatible = "mediatek,mt6397-rtc", },
{ }
};
MODULE_DEVICE_TABLE(of, mt6397_rtc_of_match);
static struct platform_driver mtk_rtc_driver = {
.driver = {
.name = "mt6397-rtc",
.of_match_table = mt6397_rtc_of_match,
.pm = &mt6397_pm_ops,
},
.probe = mtk_rtc_probe,
.remove = mtk_rtc_remove,
};
module_platform_driver(mtk_rtc_driver);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Tianping Fang <tianping.fang@mediatek.com>");
MODULE_DESCRIPTION("RTC Driver for MediaTek MT6397 PMIC");