mirror of https://gitee.com/openkylin/linux.git
494 lines
13 KiB
C
494 lines
13 KiB
C
/*
|
|
* Real Time Clock interface for Linux on Atmel AT91RM9200
|
|
*
|
|
* Copyright (C) 2002 Rick Bronson
|
|
*
|
|
* Converted to RTC class model by Andrew Victor
|
|
*
|
|
* Ported to Linux 2.6 by Steven Scholz
|
|
* Based on s3c2410-rtc.c Simtec Electronics
|
|
*
|
|
* Based on sa1100-rtc.c by Nils Faerber
|
|
* Based on rtc.c by Paul Gortmaker
|
|
*
|
|
* 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/kernel.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/time.h>
|
|
#include <linux/rtc.h>
|
|
#include <linux/bcd.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/ioctl.h>
|
|
#include <linux/completion.h>
|
|
#include <linux/io.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_device.h>
|
|
#include <linux/uaccess.h>
|
|
|
|
#include "rtc-at91rm9200.h"
|
|
|
|
#define at91_rtc_read(field) \
|
|
__raw_readl(at91_rtc_regs + field)
|
|
#define at91_rtc_write(field, val) \
|
|
__raw_writel((val), at91_rtc_regs + field)
|
|
|
|
#define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */
|
|
|
|
struct at91_rtc_config {
|
|
bool use_shadow_imr;
|
|
};
|
|
|
|
static const struct at91_rtc_config *at91_rtc_config;
|
|
static DECLARE_COMPLETION(at91_rtc_updated);
|
|
static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
|
|
static void __iomem *at91_rtc_regs;
|
|
static int irq;
|
|
static DEFINE_SPINLOCK(at91_rtc_lock);
|
|
static u32 at91_rtc_shadow_imr;
|
|
|
|
static void at91_rtc_write_ier(u32 mask)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&at91_rtc_lock, flags);
|
|
at91_rtc_shadow_imr |= mask;
|
|
at91_rtc_write(AT91_RTC_IER, mask);
|
|
spin_unlock_irqrestore(&at91_rtc_lock, flags);
|
|
}
|
|
|
|
static void at91_rtc_write_idr(u32 mask)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&at91_rtc_lock, flags);
|
|
at91_rtc_write(AT91_RTC_IDR, mask);
|
|
/*
|
|
* Register read back (of any RTC-register) needed to make sure
|
|
* IDR-register write has reached the peripheral before updating
|
|
* shadow mask.
|
|
*
|
|
* Note that there is still a possibility that the mask is updated
|
|
* before interrupts have actually been disabled in hardware. The only
|
|
* way to be certain would be to poll the IMR-register, which is is
|
|
* the very register we are trying to emulate. The register read back
|
|
* is a reasonable heuristic.
|
|
*/
|
|
at91_rtc_read(AT91_RTC_SR);
|
|
at91_rtc_shadow_imr &= ~mask;
|
|
spin_unlock_irqrestore(&at91_rtc_lock, flags);
|
|
}
|
|
|
|
static u32 at91_rtc_read_imr(void)
|
|
{
|
|
unsigned long flags;
|
|
u32 mask;
|
|
|
|
if (at91_rtc_config->use_shadow_imr) {
|
|
spin_lock_irqsave(&at91_rtc_lock, flags);
|
|
mask = at91_rtc_shadow_imr;
|
|
spin_unlock_irqrestore(&at91_rtc_lock, flags);
|
|
} else {
|
|
mask = at91_rtc_read(AT91_RTC_IMR);
|
|
}
|
|
|
|
return mask;
|
|
}
|
|
|
|
/*
|
|
* Decode time/date into rtc_time structure
|
|
*/
|
|
static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg,
|
|
struct rtc_time *tm)
|
|
{
|
|
unsigned int time, date;
|
|
|
|
/* must read twice in case it changes */
|
|
do {
|
|
time = at91_rtc_read(timereg);
|
|
date = at91_rtc_read(calreg);
|
|
} while ((time != at91_rtc_read(timereg)) ||
|
|
(date != at91_rtc_read(calreg)));
|
|
|
|
tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0);
|
|
tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8);
|
|
tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16);
|
|
|
|
/*
|
|
* The Calendar Alarm register does not have a field for
|
|
* the year - so these will return an invalid value. When an
|
|
* alarm is set, at91_alarm_year will store the current year.
|
|
*/
|
|
tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */
|
|
tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */
|
|
|
|
tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */
|
|
tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1;
|
|
tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24);
|
|
}
|
|
|
|
/*
|
|
* Read current time and date in RTC
|
|
*/
|
|
static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm);
|
|
tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
|
|
tm->tm_year = tm->tm_year - 1900;
|
|
|
|
dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
|
|
1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
|
|
tm->tm_hour, tm->tm_min, tm->tm_sec);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Set current time and date in RTC
|
|
*/
|
|
static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
unsigned long cr;
|
|
|
|
dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
|
|
1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
|
|
tm->tm_hour, tm->tm_min, tm->tm_sec);
|
|
|
|
/* Stop Time/Calendar from counting */
|
|
cr = at91_rtc_read(AT91_RTC_CR);
|
|
at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
|
|
|
|
at91_rtc_write_ier(AT91_RTC_ACKUPD);
|
|
wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
|
|
at91_rtc_write_idr(AT91_RTC_ACKUPD);
|
|
|
|
at91_rtc_write(AT91_RTC_TIMR,
|
|
bin2bcd(tm->tm_sec) << 0
|
|
| bin2bcd(tm->tm_min) << 8
|
|
| bin2bcd(tm->tm_hour) << 16);
|
|
|
|
at91_rtc_write(AT91_RTC_CALR,
|
|
bin2bcd((tm->tm_year + 1900) / 100) /* century */
|
|
| bin2bcd(tm->tm_year % 100) << 8 /* year */
|
|
| bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
|
|
| bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
|
|
| bin2bcd(tm->tm_mday) << 24);
|
|
|
|
/* Restart Time/Calendar */
|
|
cr = at91_rtc_read(AT91_RTC_CR);
|
|
at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM));
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Read alarm time and date in RTC
|
|
*/
|
|
static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
|
|
{
|
|
struct rtc_time *tm = &alrm->time;
|
|
|
|
at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
|
|
tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
|
|
tm->tm_year = at91_alarm_year - 1900;
|
|
|
|
alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM)
|
|
? 1 : 0;
|
|
|
|
dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
|
|
1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
|
|
tm->tm_hour, tm->tm_min, tm->tm_sec);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Set alarm time and date in RTC
|
|
*/
|
|
static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
|
|
{
|
|
struct rtc_time tm;
|
|
|
|
at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);
|
|
|
|
at91_alarm_year = tm.tm_year;
|
|
|
|
tm.tm_mon = alrm->time.tm_mon;
|
|
tm.tm_mday = alrm->time.tm_mday;
|
|
tm.tm_hour = alrm->time.tm_hour;
|
|
tm.tm_min = alrm->time.tm_min;
|
|
tm.tm_sec = alrm->time.tm_sec;
|
|
|
|
at91_rtc_write_idr(AT91_RTC_ALARM);
|
|
at91_rtc_write(AT91_RTC_TIMALR,
|
|
bin2bcd(tm.tm_sec) << 0
|
|
| bin2bcd(tm.tm_min) << 8
|
|
| bin2bcd(tm.tm_hour) << 16
|
|
| AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN);
|
|
at91_rtc_write(AT91_RTC_CALALR,
|
|
bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */
|
|
| bin2bcd(tm.tm_mday) << 24
|
|
| AT91_RTC_DATEEN | AT91_RTC_MTHEN);
|
|
|
|
if (alrm->enabled) {
|
|
at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
|
|
at91_rtc_write_ier(AT91_RTC_ALARM);
|
|
}
|
|
|
|
dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
|
|
at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
|
|
tm.tm_min, tm.tm_sec);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
|
|
{
|
|
dev_dbg(dev, "%s(): cmd=%08x\n", __func__, enabled);
|
|
|
|
if (enabled) {
|
|
at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
|
|
at91_rtc_write_ier(AT91_RTC_ALARM);
|
|
} else
|
|
at91_rtc_write_idr(AT91_RTC_ALARM);
|
|
|
|
return 0;
|
|
}
|
|
/*
|
|
* Provide additional RTC information in /proc/driver/rtc
|
|
*/
|
|
static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
|
|
{
|
|
unsigned long imr = at91_rtc_read_imr();
|
|
|
|
seq_printf(seq, "update_IRQ\t: %s\n",
|
|
(imr & AT91_RTC_ACKUPD) ? "yes" : "no");
|
|
seq_printf(seq, "periodic_IRQ\t: %s\n",
|
|
(imr & AT91_RTC_SECEV) ? "yes" : "no");
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* IRQ handler for the RTC
|
|
*/
|
|
static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct platform_device *pdev = dev_id;
|
|
struct rtc_device *rtc = platform_get_drvdata(pdev);
|
|
unsigned int rtsr;
|
|
unsigned long events = 0;
|
|
|
|
rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr();
|
|
if (rtsr) { /* this interrupt is shared! Is it ours? */
|
|
if (rtsr & AT91_RTC_ALARM)
|
|
events |= (RTC_AF | RTC_IRQF);
|
|
if (rtsr & AT91_RTC_SECEV)
|
|
events |= (RTC_UF | RTC_IRQF);
|
|
if (rtsr & AT91_RTC_ACKUPD)
|
|
complete(&at91_rtc_updated);
|
|
|
|
at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
|
|
|
|
rtc_update_irq(rtc, 1, events);
|
|
|
|
dev_dbg(&pdev->dev, "%s(): num=%ld, events=0x%02lx\n", __func__,
|
|
events >> 8, events & 0x000000FF);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
return IRQ_NONE; /* not handled */
|
|
}
|
|
|
|
static const struct at91_rtc_config at91rm9200_config = {
|
|
};
|
|
|
|
static const struct at91_rtc_config at91sam9x5_config = {
|
|
.use_shadow_imr = true,
|
|
};
|
|
|
|
#ifdef CONFIG_OF
|
|
static const struct of_device_id at91_rtc_dt_ids[] = {
|
|
{
|
|
.compatible = "atmel,at91rm9200-rtc",
|
|
.data = &at91rm9200_config,
|
|
}, {
|
|
.compatible = "atmel,at91sam9x5-rtc",
|
|
.data = &at91sam9x5_config,
|
|
}, {
|
|
/* sentinel */
|
|
}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids);
|
|
#endif
|
|
|
|
static const struct at91_rtc_config *
|
|
at91_rtc_get_config(struct platform_device *pdev)
|
|
{
|
|
const struct of_device_id *match;
|
|
|
|
if (pdev->dev.of_node) {
|
|
match = of_match_node(at91_rtc_dt_ids, pdev->dev.of_node);
|
|
if (!match)
|
|
return NULL;
|
|
return (const struct at91_rtc_config *)match->data;
|
|
}
|
|
|
|
return &at91rm9200_config;
|
|
}
|
|
|
|
static const struct rtc_class_ops at91_rtc_ops = {
|
|
.read_time = at91_rtc_readtime,
|
|
.set_time = at91_rtc_settime,
|
|
.read_alarm = at91_rtc_readalarm,
|
|
.set_alarm = at91_rtc_setalarm,
|
|
.proc = at91_rtc_proc,
|
|
.alarm_irq_enable = at91_rtc_alarm_irq_enable,
|
|
};
|
|
|
|
/*
|
|
* Initialize and install RTC driver
|
|
*/
|
|
static int __init at91_rtc_probe(struct platform_device *pdev)
|
|
{
|
|
struct rtc_device *rtc;
|
|
struct resource *regs;
|
|
int ret = 0;
|
|
|
|
at91_rtc_config = at91_rtc_get_config(pdev);
|
|
if (!at91_rtc_config)
|
|
return -ENODEV;
|
|
|
|
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
if (!regs) {
|
|
dev_err(&pdev->dev, "no mmio resource defined\n");
|
|
return -ENXIO;
|
|
}
|
|
|
|
irq = platform_get_irq(pdev, 0);
|
|
if (irq < 0) {
|
|
dev_err(&pdev->dev, "no irq resource defined\n");
|
|
return -ENXIO;
|
|
}
|
|
|
|
at91_rtc_regs = devm_ioremap(&pdev->dev, regs->start,
|
|
resource_size(regs));
|
|
if (!at91_rtc_regs) {
|
|
dev_err(&pdev->dev, "failed to map registers, aborting.\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
at91_rtc_write(AT91_RTC_CR, 0);
|
|
at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */
|
|
|
|
/* Disable all interrupts */
|
|
at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
|
|
AT91_RTC_SECEV | AT91_RTC_TIMEV |
|
|
AT91_RTC_CALEV);
|
|
|
|
ret = devm_request_irq(&pdev->dev, irq, at91_rtc_interrupt,
|
|
IRQF_SHARED,
|
|
"at91_rtc", pdev);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "IRQ %d already in use.\n", irq);
|
|
return ret;
|
|
}
|
|
|
|
/* cpu init code should really have flagged this device as
|
|
* being wake-capable; if it didn't, do that here.
|
|
*/
|
|
if (!device_can_wakeup(&pdev->dev))
|
|
device_init_wakeup(&pdev->dev, 1);
|
|
|
|
rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
|
|
&at91_rtc_ops, THIS_MODULE);
|
|
if (IS_ERR(rtc))
|
|
return PTR_ERR(rtc);
|
|
platform_set_drvdata(pdev, rtc);
|
|
|
|
dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n");
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Disable and remove the RTC driver
|
|
*/
|
|
static int __exit at91_rtc_remove(struct platform_device *pdev)
|
|
{
|
|
/* Disable all interrupts */
|
|
at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
|
|
AT91_RTC_SECEV | AT91_RTC_TIMEV |
|
|
AT91_RTC_CALEV);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void at91_rtc_shutdown(struct platform_device *pdev)
|
|
{
|
|
/* Disable all interrupts */
|
|
at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
|
|
AT91_RTC_SECEV | AT91_RTC_TIMEV |
|
|
AT91_RTC_CALEV);
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
|
|
/* AT91RM9200 RTC Power management control */
|
|
|
|
static u32 at91_rtc_imr;
|
|
|
|
static int at91_rtc_suspend(struct device *dev)
|
|
{
|
|
/* this IRQ is shared with DBGU and other hardware which isn't
|
|
* necessarily doing PM like we are...
|
|
*/
|
|
at91_rtc_imr = at91_rtc_read_imr()
|
|
& (AT91_RTC_ALARM|AT91_RTC_SECEV);
|
|
if (at91_rtc_imr) {
|
|
if (device_may_wakeup(dev))
|
|
enable_irq_wake(irq);
|
|
else
|
|
at91_rtc_write_idr(at91_rtc_imr);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int at91_rtc_resume(struct device *dev)
|
|
{
|
|
if (at91_rtc_imr) {
|
|
if (device_may_wakeup(dev))
|
|
disable_irq_wake(irq);
|
|
else
|
|
at91_rtc_write_ier(at91_rtc_imr);
|
|
}
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume);
|
|
|
|
static struct platform_driver at91_rtc_driver = {
|
|
.remove = __exit_p(at91_rtc_remove),
|
|
.shutdown = at91_rtc_shutdown,
|
|
.driver = {
|
|
.name = "at91_rtc",
|
|
.owner = THIS_MODULE,
|
|
.pm = &at91_rtc_pm_ops,
|
|
.of_match_table = of_match_ptr(at91_rtc_dt_ids),
|
|
},
|
|
};
|
|
|
|
module_platform_driver_probe(at91_rtc_driver, at91_rtc_probe);
|
|
|
|
MODULE_AUTHOR("Rick Bronson");
|
|
MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("platform:at91_rtc");
|