437 lines
10 KiB
C
437 lines
10 KiB
C
/*
|
|
* Real Time Clock interface for StrongARM SA1x00 and XScale PXA2xx
|
|
*
|
|
* Copyright (c) 2000 Nils Faerber
|
|
*
|
|
* Based on rtc.c by Paul Gortmaker
|
|
*
|
|
* Original Driver by Nils Faerber <nils@kernelconcepts.de>
|
|
*
|
|
* Modifications from:
|
|
* CIH <cih@coventive.com>
|
|
* Nicolas Pitre <nico@cam.org>
|
|
* Andrew Christian <andrew.christian@hp.com>
|
|
*
|
|
* Converted to the RTC subsystem and Driver Model
|
|
* by Richard Purdie <rpurdie@rpsys.net>
|
|
*
|
|
* 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/platform_device.h>
|
|
#include <linux/module.h>
|
|
#include <linux/rtc.h>
|
|
#include <linux/init.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/string.h>
|
|
#include <linux/pm.h>
|
|
#include <linux/bitops.h>
|
|
|
|
#include <asm/hardware.h>
|
|
#include <asm/irq.h>
|
|
|
|
#ifdef CONFIG_ARCH_PXA
|
|
#include <asm/arch/pxa-regs.h>
|
|
#endif
|
|
|
|
#define TIMER_FREQ CLOCK_TICK_RATE
|
|
#define RTC_DEF_DIVIDER 32768 - 1
|
|
#define RTC_DEF_TRIM 0
|
|
|
|
static unsigned long rtc_freq = 1024;
|
|
static struct rtc_time rtc_alarm;
|
|
static DEFINE_SPINLOCK(sa1100_rtc_lock);
|
|
|
|
static inline int rtc_periodic_alarm(struct rtc_time *tm)
|
|
{
|
|
return (tm->tm_year == -1) ||
|
|
((unsigned)tm->tm_mon >= 12) ||
|
|
((unsigned)(tm->tm_mday - 1) >= 31) ||
|
|
((unsigned)tm->tm_hour > 23) ||
|
|
((unsigned)tm->tm_min > 59) ||
|
|
((unsigned)tm->tm_sec > 59);
|
|
}
|
|
|
|
/*
|
|
* Calculate the next alarm time given the requested alarm time mask
|
|
* and the current time.
|
|
*/
|
|
static void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now, struct rtc_time *alrm)
|
|
{
|
|
unsigned long next_time;
|
|
unsigned long now_time;
|
|
|
|
next->tm_year = now->tm_year;
|
|
next->tm_mon = now->tm_mon;
|
|
next->tm_mday = now->tm_mday;
|
|
next->tm_hour = alrm->tm_hour;
|
|
next->tm_min = alrm->tm_min;
|
|
next->tm_sec = alrm->tm_sec;
|
|
|
|
rtc_tm_to_time(now, &now_time);
|
|
rtc_tm_to_time(next, &next_time);
|
|
|
|
if (next_time < now_time) {
|
|
/* Advance one day */
|
|
next_time += 60 * 60 * 24;
|
|
rtc_time_to_tm(next_time, next);
|
|
}
|
|
}
|
|
|
|
static int rtc_update_alarm(struct rtc_time *alrm)
|
|
{
|
|
struct rtc_time alarm_tm, now_tm;
|
|
unsigned long now, time;
|
|
int ret;
|
|
|
|
do {
|
|
now = RCNR;
|
|
rtc_time_to_tm(now, &now_tm);
|
|
rtc_next_alarm_time(&alarm_tm, &now_tm, alrm);
|
|
ret = rtc_tm_to_time(&alarm_tm, &time);
|
|
if (ret != 0)
|
|
break;
|
|
|
|
RTSR = RTSR & (RTSR_HZE|RTSR_ALE|RTSR_AL);
|
|
RTAR = time;
|
|
} while (now != RCNR);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static irqreturn_t sa1100_rtc_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(dev_id);
|
|
struct rtc_device *rtc = platform_get_drvdata(pdev);
|
|
unsigned int rtsr;
|
|
unsigned long events = 0;
|
|
|
|
spin_lock(&sa1100_rtc_lock);
|
|
|
|
rtsr = RTSR;
|
|
/* clear interrupt sources */
|
|
RTSR = 0;
|
|
RTSR = (RTSR_AL | RTSR_HZ) & (rtsr >> 2);
|
|
|
|
/* clear alarm interrupt if it has occurred */
|
|
if (rtsr & RTSR_AL)
|
|
rtsr &= ~RTSR_ALE;
|
|
RTSR = rtsr & (RTSR_ALE | RTSR_HZE);
|
|
|
|
/* update irq data & counter */
|
|
if (rtsr & RTSR_AL)
|
|
events |= RTC_AF | RTC_IRQF;
|
|
if (rtsr & RTSR_HZ)
|
|
events |= RTC_UF | RTC_IRQF;
|
|
|
|
rtc_update_irq(rtc, 1, events);
|
|
|
|
if (rtsr & RTSR_AL && rtc_periodic_alarm(&rtc_alarm))
|
|
rtc_update_alarm(&rtc_alarm);
|
|
|
|
spin_unlock(&sa1100_rtc_lock);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int rtc_timer1_count;
|
|
|
|
static irqreturn_t timer1_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(dev_id);
|
|
struct rtc_device *rtc = platform_get_drvdata(pdev);
|
|
|
|
/*
|
|
* If we match for the first time, rtc_timer1_count will be 1.
|
|
* Otherwise, we wrapped around (very unlikely but
|
|
* still possible) so compute the amount of missed periods.
|
|
* The match reg is updated only when the data is actually retrieved
|
|
* to avoid unnecessary interrupts.
|
|
*/
|
|
OSSR = OSSR_M1; /* clear match on timer1 */
|
|
|
|
rtc_update_irq(rtc, rtc_timer1_count, RTC_PF | RTC_IRQF);
|
|
|
|
if (rtc_timer1_count == 1)
|
|
rtc_timer1_count = (rtc_freq * ((1<<30)/(TIMER_FREQ>>2)));
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int sa1100_rtc_read_callback(struct device *dev, int data)
|
|
{
|
|
if (data & RTC_PF) {
|
|
/* interpolate missed periods and set match for the next */
|
|
unsigned long period = TIMER_FREQ/rtc_freq;
|
|
unsigned long oscr = OSCR;
|
|
unsigned long osmr1 = OSMR1;
|
|
unsigned long missed = (oscr - osmr1)/period;
|
|
data += missed << 8;
|
|
OSSR = OSSR_M1; /* clear match on timer 1 */
|
|
OSMR1 = osmr1 + (missed + 1)*period;
|
|
/* Ensure we didn't miss another match in the mean time.
|
|
* Here we compare (match - OSCR) 8 instead of 0 --
|
|
* see comment in pxa_timer_interrupt() for explanation.
|
|
*/
|
|
while( (signed long)((osmr1 = OSMR1) - OSCR) <= 8 ) {
|
|
data += 0x100;
|
|
OSSR = OSSR_M1; /* clear match on timer 1 */
|
|
OSMR1 = osmr1 + period;
|
|
}
|
|
}
|
|
return data;
|
|
}
|
|
|
|
static int sa1100_rtc_open(struct device *dev)
|
|
{
|
|
int ret;
|
|
|
|
ret = request_irq(IRQ_RTC1Hz, sa1100_rtc_interrupt, IRQF_DISABLED,
|
|
"rtc 1Hz", dev);
|
|
if (ret) {
|
|
dev_err(dev, "IRQ %d already in use.\n", IRQ_RTC1Hz);
|
|
goto fail_ui;
|
|
}
|
|
ret = request_irq(IRQ_RTCAlrm, sa1100_rtc_interrupt, IRQF_DISABLED,
|
|
"rtc Alrm", dev);
|
|
if (ret) {
|
|
dev_err(dev, "IRQ %d already in use.\n", IRQ_RTCAlrm);
|
|
goto fail_ai;
|
|
}
|
|
ret = request_irq(IRQ_OST1, timer1_interrupt, IRQF_DISABLED,
|
|
"rtc timer", dev);
|
|
if (ret) {
|
|
dev_err(dev, "IRQ %d already in use.\n", IRQ_OST1);
|
|
goto fail_pi;
|
|
}
|
|
return 0;
|
|
|
|
fail_pi:
|
|
free_irq(IRQ_RTCAlrm, dev);
|
|
fail_ai:
|
|
free_irq(IRQ_RTC1Hz, dev);
|
|
fail_ui:
|
|
return ret;
|
|
}
|
|
|
|
static void sa1100_rtc_release(struct device *dev)
|
|
{
|
|
spin_lock_irq(&sa1100_rtc_lock);
|
|
RTSR = 0;
|
|
OIER &= ~OIER_E1;
|
|
OSSR = OSSR_M1;
|
|
spin_unlock_irq(&sa1100_rtc_lock);
|
|
|
|
free_irq(IRQ_OST1, dev);
|
|
free_irq(IRQ_RTCAlrm, dev);
|
|
free_irq(IRQ_RTC1Hz, dev);
|
|
}
|
|
|
|
|
|
static int sa1100_rtc_ioctl(struct device *dev, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
switch(cmd) {
|
|
case RTC_AIE_OFF:
|
|
spin_lock_irq(&sa1100_rtc_lock);
|
|
RTSR &= ~RTSR_ALE;
|
|
spin_unlock_irq(&sa1100_rtc_lock);
|
|
return 0;
|
|
case RTC_AIE_ON:
|
|
spin_lock_irq(&sa1100_rtc_lock);
|
|
RTSR |= RTSR_ALE;
|
|
spin_unlock_irq(&sa1100_rtc_lock);
|
|
return 0;
|
|
case RTC_UIE_OFF:
|
|
spin_lock_irq(&sa1100_rtc_lock);
|
|
RTSR &= ~RTSR_HZE;
|
|
spin_unlock_irq(&sa1100_rtc_lock);
|
|
return 0;
|
|
case RTC_UIE_ON:
|
|
spin_lock_irq(&sa1100_rtc_lock);
|
|
RTSR |= RTSR_HZE;
|
|
spin_unlock_irq(&sa1100_rtc_lock);
|
|
return 0;
|
|
case RTC_PIE_OFF:
|
|
spin_lock_irq(&sa1100_rtc_lock);
|
|
OIER &= ~OIER_E1;
|
|
spin_unlock_irq(&sa1100_rtc_lock);
|
|
return 0;
|
|
case RTC_PIE_ON:
|
|
spin_lock_irq(&sa1100_rtc_lock);
|
|
OSMR1 = TIMER_FREQ/rtc_freq + OSCR;
|
|
OIER |= OIER_E1;
|
|
rtc_timer1_count = 1;
|
|
spin_unlock_irq(&sa1100_rtc_lock);
|
|
return 0;
|
|
case RTC_IRQP_READ:
|
|
return put_user(rtc_freq, (unsigned long *)arg);
|
|
case RTC_IRQP_SET:
|
|
if (arg < 1 || arg > TIMER_FREQ)
|
|
return -EINVAL;
|
|
rtc_freq = arg;
|
|
return 0;
|
|
}
|
|
return -ENOIOCTLCMD;
|
|
}
|
|
|
|
static int sa1100_rtc_read_time(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
rtc_time_to_tm(RCNR, tm);
|
|
return 0;
|
|
}
|
|
|
|
static int sa1100_rtc_set_time(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
unsigned long time;
|
|
int ret;
|
|
|
|
ret = rtc_tm_to_time(tm, &time);
|
|
if (ret == 0)
|
|
RCNR = time;
|
|
return ret;
|
|
}
|
|
|
|
static int sa1100_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
|
|
{
|
|
u32 rtsr;
|
|
|
|
memcpy(&alrm->time, &rtc_alarm, sizeof(struct rtc_time));
|
|
rtsr = RTSR;
|
|
alrm->enabled = (rtsr & RTSR_ALE) ? 1 : 0;
|
|
alrm->pending = (rtsr & RTSR_AL) ? 1 : 0;
|
|
return 0;
|
|
}
|
|
|
|
static int sa1100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
|
|
{
|
|
int ret;
|
|
|
|
spin_lock_irq(&sa1100_rtc_lock);
|
|
ret = rtc_update_alarm(&alrm->time);
|
|
if (ret == 0) {
|
|
if (alrm->enabled)
|
|
RTSR |= RTSR_ALE;
|
|
else
|
|
RTSR &= ~RTSR_ALE;
|
|
}
|
|
spin_unlock_irq(&sa1100_rtc_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int sa1100_rtc_proc(struct device *dev, struct seq_file *seq)
|
|
{
|
|
seq_printf(seq, "trim/divider\t: 0x%08x\n", (u32) RTTR);
|
|
seq_printf(seq, "update_IRQ\t: %s\n",
|
|
(RTSR & RTSR_HZE) ? "yes" : "no");
|
|
seq_printf(seq, "periodic_IRQ\t: %s\n",
|
|
(OIER & OIER_E1) ? "yes" : "no");
|
|
seq_printf(seq, "periodic_freq\t: %ld\n", rtc_freq);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct rtc_class_ops sa1100_rtc_ops = {
|
|
.open = sa1100_rtc_open,
|
|
.read_callback = sa1100_rtc_read_callback,
|
|
.release = sa1100_rtc_release,
|
|
.ioctl = sa1100_rtc_ioctl,
|
|
.read_time = sa1100_rtc_read_time,
|
|
.set_time = sa1100_rtc_set_time,
|
|
.read_alarm = sa1100_rtc_read_alarm,
|
|
.set_alarm = sa1100_rtc_set_alarm,
|
|
.proc = sa1100_rtc_proc,
|
|
};
|
|
|
|
static int sa1100_rtc_probe(struct platform_device *pdev)
|
|
{
|
|
struct rtc_device *rtc;
|
|
|
|
/*
|
|
* According to the manual we should be able to let RTTR be zero
|
|
* and then a default diviser for a 32.768KHz clock is used.
|
|
* Apparently this doesn't work, at least for my SA1110 rev 5.
|
|
* If the clock divider is uninitialized then reset it to the
|
|
* default value to get the 1Hz clock.
|
|
*/
|
|
if (RTTR == 0) {
|
|
RTTR = RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16);
|
|
dev_warn(&pdev->dev, "warning: initializing default clock divider/trim value\n");
|
|
/* The current RTC value probably doesn't make sense either */
|
|
RCNR = 0;
|
|
}
|
|
|
|
device_init_wakeup(&pdev->dev, 1);
|
|
|
|
rtc = rtc_device_register(pdev->name, &pdev->dev, &sa1100_rtc_ops,
|
|
THIS_MODULE);
|
|
|
|
if (IS_ERR(rtc))
|
|
return PTR_ERR(rtc);
|
|
|
|
platform_set_drvdata(pdev, rtc);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int sa1100_rtc_remove(struct platform_device *pdev)
|
|
{
|
|
struct rtc_device *rtc = platform_get_drvdata(pdev);
|
|
|
|
if (rtc)
|
|
rtc_device_unregister(rtc);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM
|
|
static int sa1100_rtc_suspend(struct platform_device *pdev, pm_message_t state)
|
|
{
|
|
if (device_may_wakeup(&pdev->dev))
|
|
enable_irq_wake(IRQ_RTCAlrm);
|
|
return 0;
|
|
}
|
|
|
|
static int sa1100_rtc_resume(struct platform_device *pdev)
|
|
{
|
|
if (device_may_wakeup(&pdev->dev))
|
|
disable_irq_wake(IRQ_RTCAlrm);
|
|
return 0;
|
|
}
|
|
#else
|
|
#define sa1100_rtc_suspend NULL
|
|
#define sa1100_rtc_resume NULL
|
|
#endif
|
|
|
|
static struct platform_driver sa1100_rtc_driver = {
|
|
.probe = sa1100_rtc_probe,
|
|
.remove = sa1100_rtc_remove,
|
|
.suspend = sa1100_rtc_suspend,
|
|
.resume = sa1100_rtc_resume,
|
|
.driver = {
|
|
.name = "sa1100-rtc",
|
|
},
|
|
};
|
|
|
|
static int __init sa1100_rtc_init(void)
|
|
{
|
|
return platform_driver_register(&sa1100_rtc_driver);
|
|
}
|
|
|
|
static void __exit sa1100_rtc_exit(void)
|
|
{
|
|
platform_driver_unregister(&sa1100_rtc_driver);
|
|
}
|
|
|
|
module_init(sa1100_rtc_init);
|
|
module_exit(sa1100_rtc_exit);
|
|
|
|
MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
|
|
MODULE_DESCRIPTION("SA11x0/PXA2xx Realtime Clock Driver (RTC)");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("platform:sa1100-rtc");
|