- 根目录:
- drivers
- rtc
- rtc-rc5t583.c
/*
* rtc-rc5t583.c -- RICOH RC5T583 Real Time Clock
*
* Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
* Author: Venu Byravarasu <vbyravarasu@nvidia.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/mfd/rc5t583.h>
struct rc5t583_rtc {
struct rtc_device *rtc;
/* To store the list of enabled interrupts, during system suspend */
u32 irqen;
};
/* Total number of RTC registers needed to set time*/
#define NUM_TIME_REGS (RC5T583_RTC_YEAR - RC5T583_RTC_SEC + 1)
/* Total number of RTC registers needed to set Y-Alarm*/
#define NUM_YAL_REGS (RC5T583_RTC_AY_YEAR - RC5T583_RTC_AY_MIN + 1)
/* Set Y-Alarm interrupt */
#define SET_YAL BIT(5)
/* Get Y-Alarm interrupt status*/
#define GET_YAL_STATUS BIT(3)
static int rc5t583_rtc_alarm_irq_enable(struct device *dev, unsigned enabled)
{
struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
u8 val;
/* Set Y-Alarm, based on 'enabled' */
val = enabled ? SET_YAL : 0;
return regmap_update_bits(rc5t583->regmap, RC5T583_RTC_CTL1, SET_YAL,
val);
}
/*
* Gets current rc5t583 RTC time and date parameters.
*
* The RTC's time/alarm representation is not what gmtime(3) requires
* Linux to use:
*
* - Months are 1..12 vs Linux 0-11
* - Years are 0..99 vs Linux 1900..N (we assume 21st century)
*/
static int rc5t583_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
u8 rtc_data[NUM_TIME_REGS];
int ret;
ret = regmap_bulk_read(rc5t583->regmap, RC5T583_RTC_SEC, rtc_data,
NUM_TIME_REGS);
if (ret < 0) {
dev_err(dev, "RTC read time failed with err:%d\n", ret);
return ret;
}
tm->tm_sec = bcd2bin(rtc_data[0]);
tm->tm_min = bcd2bin(rtc_data[1]);
tm->tm_hour = bcd2bin(rtc_data[2]);
tm->tm_wday = bcd2bin(rtc_data[3]);
tm->tm_mday = bcd2bin(rtc_data[4]);
tm->tm_mon = bcd2bin(rtc_data[5]) - 1;
tm->tm_year = bcd2bin(rtc_data[6]) + 100;
return ret;
}
static int rc5t583_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
unsigned char rtc_data[NUM_TIME_REGS];
int ret;
rtc_data[0] = bin2bcd(tm->tm_sec);
rtc_data[1] = bin2bcd(tm->tm_min);
rtc_data[2] = bin2bcd(tm->tm_hour);
rtc_data[3] = bin2bcd(tm->tm_wday);
rtc_data[4] = bin2bcd(tm->tm_mday);
rtc_data[5] = bin2bcd(tm->tm_mon + 1);
rtc_data[6] = bin2bcd(tm->tm_year - 100);
ret = regmap_bulk_write(rc5t583->regmap, RC5T583_RTC_SEC, rtc_data,
NUM_TIME_REGS);
if (ret < 0) {
dev_err(dev, "RTC set time failed with error %d\n", ret);
return ret;
}
return ret;
}
static int rc5t583_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
unsigned char alarm_data[NUM_YAL_REGS];
u32 interrupt_enable;
int ret;
ret = regmap_bulk_read(rc5t583->regmap, RC5T583_RTC_AY_MIN, alarm_data,
NUM_YAL_REGS);
if (ret < 0) {
dev_err(dev, "rtc_read_alarm error %d\n", ret);
return ret;
}
alm->time.tm_min = bcd2bin(alarm_data[0]);
alm->time.tm_hour = bcd2bin(alarm_data[1]);
alm->time.tm_mday = bcd2bin(alarm_data[2]);
alm->time.tm_mon = bcd2bin(alarm_data[3]) - 1;
alm->time.tm_year = bcd2bin(alarm_data[4]) + 100;
ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL1, &interrupt_enable);
if (ret < 0)
return ret;
/* check if YALE is set */
if (interrupt_enable & SET_YAL)
alm->enabled = 1;
return ret;
}
static int rc5t583_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
unsigned char alarm_data[NUM_YAL_REGS];
int ret;
ret = rc5t583_rtc_alarm_irq_enable(dev, 0);
if (ret)
return ret;
alarm_data[0] = bin2bcd(alm->time.tm_min);
alarm_data[1] = bin2bcd(alm->time.tm_hour);
alarm_data[2] = bin2bcd(alm->time.tm_mday);
alarm_data[3] = bin2bcd(alm->time.tm_mon + 1);
alarm_data[4] = bin2bcd(alm->time.tm_year - 100);
ret = regmap_bulk_write(rc5t583->regmap, RC5T583_RTC_AY_MIN, alarm_data,
NUM_YAL_REGS);
if (ret) {
dev_err(dev, "rtc_set_alarm error %d\n", ret);
return ret;
}
if (alm->enabled)
ret = rc5t583_rtc_alarm_irq_enable(dev, 1);
return ret;
}
static irqreturn_t rc5t583_rtc_interrupt(int irq, void *rtc)
{
struct device *dev = rtc;
struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);
unsigned long events = 0;
int ret;
u32 rtc_reg;
ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL2, &rtc_reg);
if (ret < 0)
return IRQ_NONE;
if (rtc_reg & GET_YAL_STATUS) {
events = RTC_IRQF | RTC_AF;
/* clear pending Y-alarm interrupt bit */
rtc_reg &= ~GET_YAL_STATUS;
}
ret = regmap_write(rc5t583->regmap, RC5T583_RTC_CTL2, rtc_reg);
if (ret)
return IRQ_NONE;
/* Notify RTC core on event */
rtc_update_irq(rc5t583_rtc->rtc, 1, events);
return IRQ_HANDLED;
}
static const struct rtc_class_ops rc5t583_rtc_ops = {
.read_time = rc5t583_rtc_read_time,
.set_time = rc5t583_rtc_set_time,
.read_alarm = rc5t583_rtc_read_alarm,
.set_alarm = rc5t583_rtc_set_alarm,
.alarm_irq_enable = rc5t583_rtc_alarm_irq_enable,
};
static int rc5t583_rtc_probe(struct platform_device *pdev)
{
struct rc5t583 *rc5t583 = dev_get_drvdata(pdev->dev.parent);
struct rc5t583_rtc *ricoh_rtc;
struct rc5t583_platform_data *pmic_plat_data;
int ret;
int irq;
ricoh_rtc = devm_kzalloc(&pdev->dev, sizeof(struct rc5t583_rtc),
GFP_KERNEL);
if (!ricoh_rtc)
return -ENOMEM;
platform_set_drvdata(pdev, ricoh_rtc);
/* Clear pending interrupts */
ret = regmap_write(rc5t583->regmap, RC5T583_RTC_CTL2, 0);
if (ret < 0)
return ret;
/* clear RTC Adjust register */
ret = regmap_write(rc5t583->regmap, RC5T583_RTC_ADJ, 0);
if (ret < 0) {
dev_err(&pdev->dev, "unable to program rtc_adjust reg\n");
return -EBUSY;
}
pmic_plat_data = dev_get_platdata(rc5t583->dev);
irq = pmic_plat_data->irq_base;
if (irq <= 0) {
dev_warn(&pdev->dev, "Wake up is not possible as irq = %d\n",
irq);
return ret;
}
irq += RC5T583_IRQ_YALE;
ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
rc5t583_rtc_interrupt, IRQF_TRIGGER_LOW,
"rtc-rc5t583", &pdev->dev);
if (ret < 0) {
dev_err(&pdev->dev, "IRQ is not free.\n");
return ret;
}
device_init_wakeup(&pdev->dev, 1);
ricoh_rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
&rc5t583_rtc_ops, THIS_MODULE);
if (IS_ERR(ricoh_rtc->rtc)) {
ret = PTR_ERR(ricoh_rtc->rtc);
dev_err(&pdev->dev, "RTC device register: err %d\n", ret);
return ret;
}
return 0;
}
/*
* Disable rc5t583 RTC interrupts.
* Sets status flag to free.
*/
static int rc5t583_rtc_remove(struct platform_device *pdev)
{
struct rc5t583_rtc *rc5t583_rtc = platform_get_drvdata(pdev);
rc5t583_rtc_alarm_irq_enable(&rc5t583_rtc->rtc->dev, 0);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int rc5t583_rtc_suspend(struct device *dev)
{
struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);
int ret;
/* Store current list of enabled interrupts*/
ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL1,
&rc5t583_rtc->irqen);
return ret;
}
static int rc5t583_rtc_resume(struct device *dev)
{
struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);
/* Restore list of enabled interrupts before suspend */
return regmap_write(rc5t583->regmap, RC5T583_RTC_CTL1,
rc5t583_rtc->irqen);
}
#endif
static SIMPLE_DEV_PM_OPS(rc5t583_rtc_pm_ops, rc5t583_rtc_suspend,
rc5t583_rtc_resume);
static struct platform_driver rc5t583_rtc_driver = {
.probe = rc5t583_rtc_probe,
.remove = rc5t583_rtc_remove,
.driver = {
.owner = THIS_MODULE,
.name = "rtc-rc5t583",
.pm = &rc5t583_rtc_pm_ops,
},
};
module_platform_driver(rc5t583_rtc_driver);
MODULE_ALIAS("platform:rtc-rc5t583");
MODULE_AUTHOR("Venu Byravarasu <vbyravarasu@nvidia.com>");
MODULE_LICENSE("GPL v2");