blob: 4b9291dd444354ab1f2f374c26d2d0069266b800 [file] [log] [blame]
/*
* Driver for NEC VR4100 series Real Time Clock unit.
*
* Copyright (C) 2003-2006 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
*
* 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.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <asm/div64.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/vr41xx/vr41xx.h>
MODULE_AUTHOR("Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>");
MODULE_DESCRIPTION("NEC VR4100 series RTC driver");
MODULE_LICENSE("GPL");
#define RTC1_TYPE1_START 0x0b0000c0UL
#define RTC1_TYPE1_END 0x0b0000dfUL
#define RTC2_TYPE1_START 0x0b0001c0UL
#define RTC2_TYPE1_END 0x0b0001dfUL
#define RTC1_TYPE2_START 0x0f000100UL
#define RTC1_TYPE2_END 0x0f00011fUL
#define RTC2_TYPE2_START 0x0f000120UL
#define RTC2_TYPE2_END 0x0f00013fUL
#define RTC1_SIZE 0x20
#define RTC2_SIZE 0x20
/* RTC 1 registers */
#define ETIMELREG 0x00
#define ETIMEMREG 0x02
#define ETIMEHREG 0x04
/* RFU */
#define ECMPLREG 0x08
#define ECMPMREG 0x0a
#define ECMPHREG 0x0c
/* RFU */
#define RTCL1LREG 0x10
#define RTCL1HREG 0x12
#define RTCL1CNTLREG 0x14
#define RTCL1CNTHREG 0x16
#define RTCL2LREG 0x18
#define RTCL2HREG 0x1a
#define RTCL2CNTLREG 0x1c
#define RTCL2CNTHREG 0x1e
/* RTC 2 registers */
#define TCLKLREG 0x00
#define TCLKHREG 0x02
#define TCLKCNTLREG 0x04
#define TCLKCNTHREG 0x06
/* RFU */
#define RTCINTREG 0x1e
#define TCLOCK_INT 0x08
#define RTCLONG2_INT 0x04
#define RTCLONG1_INT 0x02
#define ELAPSEDTIME_INT 0x01
#define RTC_FREQUENCY 32768
#define MAX_PERIODIC_RATE 6553
static void __iomem *rtc1_base;
static void __iomem *rtc2_base;
#define rtc1_read(offset) readw(rtc1_base + (offset))
#define rtc1_write(offset, value) writew((value), rtc1_base + (offset))
#define rtc2_read(offset) readw(rtc2_base + (offset))
#define rtc2_write(offset, value) writew((value), rtc2_base + (offset))
static unsigned long epoch = 1970; /* Jan 1 1970 00:00:00 */
static DEFINE_SPINLOCK(rtc_lock);
static char rtc_name[] = "RTC";
static unsigned long periodic_frequency;
static unsigned long periodic_count;
struct resource rtc_resource[2] = {
{ .name = rtc_name,
.flags = IORESOURCE_MEM, },
{ .name = rtc_name,
.flags = IORESOURCE_MEM, },
};
static inline unsigned long read_elapsed_second(void)
{
unsigned long first_low, first_mid, first_high;
unsigned long second_low, second_mid, second_high;
do {
first_low = rtc1_read(ETIMELREG);
first_mid = rtc1_read(ETIMEMREG);
first_high = rtc1_read(ETIMEHREG);
second_low = rtc1_read(ETIMELREG);
second_mid = rtc1_read(ETIMEMREG);
second_high = rtc1_read(ETIMEHREG);
} while (first_low != second_low || first_mid != second_mid ||
first_high != second_high);
return (first_high << 17) | (first_mid << 1) | (first_low >> 15);
}
static inline void write_elapsed_second(unsigned long sec)
{
spin_lock_irq(&rtc_lock);
rtc1_write(ETIMELREG, (uint16_t)(sec << 15));
rtc1_write(ETIMEMREG, (uint16_t)(sec >> 1));
rtc1_write(ETIMEHREG, (uint16_t)(sec >> 17));
spin_unlock_irq(&rtc_lock);
}
static void vr41xx_rtc_release(struct device *dev)
{
spin_lock_irq(&rtc_lock);
rtc1_write(ECMPLREG, 0);
rtc1_write(ECMPMREG, 0);
rtc1_write(ECMPHREG, 0);
rtc1_write(RTCL1LREG, 0);
rtc1_write(RTCL1HREG, 0);
spin_unlock_irq(&rtc_lock);
disable_irq(ELAPSEDTIME_IRQ);
disable_irq(RTCLONG1_IRQ);
}
static int vr41xx_rtc_read_time(struct device *dev, struct rtc_time *time)
{
unsigned long epoch_sec, elapsed_sec;
epoch_sec = mktime(epoch, 1, 1, 0, 0, 0);
elapsed_sec = read_elapsed_second();
rtc_time_to_tm(epoch_sec + elapsed_sec, time);
return 0;
}
static int vr41xx_rtc_set_time(struct device *dev, struct rtc_time *time)
{
unsigned long epoch_sec, current_sec;
epoch_sec = mktime(epoch, 1, 1, 0, 0, 0);
current_sec = mktime(time->tm_year + 1900, time->tm_mon + 1, time->tm_mday,
time->tm_hour, time->tm_min, time->tm_sec);
write_elapsed_second(current_sec - epoch_sec);
return 0;
}
static int vr41xx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
{
unsigned long low, mid, high;
struct rtc_time *time = &wkalrm->time;
spin_lock_irq(&rtc_lock);
low = rtc1_read(ECMPLREG);
mid = rtc1_read(ECMPMREG);
high = rtc1_read(ECMPHREG);
spin_unlock_irq(&rtc_lock);
rtc_time_to_tm((high << 17) | (mid << 1) | (low >> 15), time);
return 0;
}
static int vr41xx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
{
unsigned long alarm_sec;
struct rtc_time *time = &wkalrm->time;
alarm_sec = mktime(time->tm_year + 1900, time->tm_mon + 1, time->tm_mday,
time->tm_hour, time->tm_min, time->tm_sec);
spin_lock_irq(&rtc_lock);
rtc1_write(ECMPLREG, (uint16_t)(alarm_sec << 15));
rtc1_write(ECMPMREG, (uint16_t)(alarm_sec >> 1));
rtc1_write(ECMPHREG, (uint16_t)(alarm_sec >> 17));
spin_unlock_irq(&rtc_lock);
return 0;
}
static int vr41xx_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
{
unsigned long count;
switch (cmd) {
case RTC_AIE_ON:
enable_irq(ELAPSEDTIME_IRQ);
break;
case RTC_AIE_OFF:
disable_irq(ELAPSEDTIME_IRQ);
break;
case RTC_PIE_ON:
enable_irq(RTCLONG1_IRQ);
break;
case RTC_PIE_OFF:
disable_irq(RTCLONG1_IRQ);
break;
case RTC_IRQP_READ:
return put_user(periodic_frequency, (unsigned long __user *)arg);
break;
case RTC_IRQP_SET:
if (arg > MAX_PERIODIC_RATE)
return -EINVAL;
periodic_frequency = arg;
count = RTC_FREQUENCY;
do_div(count, arg);
periodic_count = count;
spin_lock_irq(&rtc_lock);
rtc1_write(RTCL1LREG, count);
rtc1_write(RTCL1HREG, count >> 16);
spin_unlock_irq(&rtc_lock);
break;
case RTC_EPOCH_READ:
return put_user(epoch, (unsigned long __user *)arg);
case RTC_EPOCH_SET:
/* Doesn't support before 1900 */
if (arg < 1900)
return -EINVAL;
epoch = arg;
break;
default:
return -ENOIOCTLCMD;
}
return 0;
}
static irqreturn_t elapsedtime_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
struct platform_device *pdev = (struct platform_device *)dev_id;
struct rtc_device *rtc = platform_get_drvdata(pdev);
rtc2_write(RTCINTREG, ELAPSEDTIME_INT);
rtc_update_irq(&rtc->class_dev, 1, RTC_AF);
return IRQ_HANDLED;
}
static irqreturn_t rtclong1_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
struct platform_device *pdev = (struct platform_device *)dev_id;
struct rtc_device *rtc = platform_get_drvdata(pdev);
unsigned long count = periodic_count;
rtc2_write(RTCINTREG, RTCLONG1_INT);
rtc1_write(RTCL1LREG, count);
rtc1_write(RTCL1HREG, count >> 16);
rtc_update_irq(&rtc->class_dev, 1, RTC_PF);
return IRQ_HANDLED;
}
static struct rtc_class_ops vr41xx_rtc_ops = {
.release = vr41xx_rtc_release,
.ioctl = vr41xx_rtc_ioctl,
.read_time = vr41xx_rtc_read_time,
.set_time = vr41xx_rtc_set_time,
.read_alarm = vr41xx_rtc_read_alarm,
.set_alarm = vr41xx_rtc_set_alarm,
};
static int __devinit rtc_probe(struct platform_device *pdev)
{
struct rtc_device *rtc;
unsigned int irq;
int retval;
if (pdev->num_resources != 2)
return -EBUSY;
rtc1_base = ioremap(pdev->resource[0].start, RTC1_SIZE);
if (rtc1_base == NULL)
return -EBUSY;
rtc2_base = ioremap(pdev->resource[1].start, RTC2_SIZE);
if (rtc2_base == NULL) {
iounmap(rtc1_base);
rtc1_base = NULL;
return -EBUSY;
}
rtc = rtc_device_register(rtc_name, &pdev->dev, &vr41xx_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc)) {
iounmap(rtc1_base);
iounmap(rtc2_base);
rtc1_base = NULL;
rtc2_base = NULL;
return PTR_ERR(rtc);
}
spin_lock_irq(&rtc_lock);
rtc1_write(ECMPLREG, 0);
rtc1_write(ECMPMREG, 0);
rtc1_write(ECMPHREG, 0);
rtc1_write(RTCL1LREG, 0);
rtc1_write(RTCL1HREG, 0);
spin_unlock_irq(&rtc_lock);
irq = ELAPSEDTIME_IRQ;
retval = request_irq(irq, elapsedtime_interrupt, SA_INTERRUPT,
"elapsed_time", pdev);
if (retval == 0) {
irq = RTCLONG1_IRQ;
retval = request_irq(irq, rtclong1_interrupt, SA_INTERRUPT,
"rtclong1", pdev);
}
if (retval < 0) {
printk(KERN_ERR "rtc: IRQ%d is busy\n", irq);
rtc_device_unregister(rtc);
if (irq == RTCLONG1_IRQ)
free_irq(ELAPSEDTIME_IRQ, NULL);
iounmap(rtc1_base);
iounmap(rtc2_base);
rtc1_base = NULL;
rtc2_base = NULL;
return retval;
}
platform_set_drvdata(pdev, rtc);
disable_irq(ELAPSEDTIME_IRQ);
disable_irq(RTCLONG1_IRQ);
printk(KERN_INFO "rtc: Real Time Clock of NEC VR4100 series\n");
return 0;
}
static int __devexit rtc_remove(struct platform_device *pdev)
{
struct rtc_device *rtc;
rtc = platform_get_drvdata(pdev);
if (rtc != NULL)
rtc_device_unregister(rtc);
platform_set_drvdata(pdev, NULL);
free_irq(ELAPSEDTIME_IRQ, NULL);
free_irq(RTCLONG1_IRQ, NULL);
if (rtc1_base != NULL)
iounmap(rtc1_base);
if (rtc2_base != NULL)
iounmap(rtc2_base);
return 0;
}
static struct platform_device *rtc_platform_device;
static struct platform_driver rtc_platform_driver = {
.probe = rtc_probe,
.remove = __devexit_p(rtc_remove),
.driver = {
.name = rtc_name,
.owner = THIS_MODULE,
},
};
static int __init vr41xx_rtc_init(void)
{
int retval;
switch (current_cpu_data.cputype) {
case CPU_VR4111:
case CPU_VR4121:
rtc_resource[0].start = RTC1_TYPE1_START;
rtc_resource[0].end = RTC1_TYPE1_END;
rtc_resource[1].start = RTC2_TYPE1_START;
rtc_resource[1].end = RTC2_TYPE1_END;
break;
case CPU_VR4122:
case CPU_VR4131:
case CPU_VR4133:
rtc_resource[0].start = RTC1_TYPE2_START;
rtc_resource[0].end = RTC1_TYPE2_END;
rtc_resource[1].start = RTC2_TYPE2_START;
rtc_resource[1].end = RTC2_TYPE2_END;
break;
default:
return -ENODEV;
break;
}
rtc_platform_device = platform_device_alloc("RTC", -1);
if (rtc_platform_device == NULL)
return -ENOMEM;
retval = platform_device_add_resources(rtc_platform_device,
rtc_resource, ARRAY_SIZE(rtc_resource));
if (retval == 0)
retval = platform_device_add(rtc_platform_device);
if (retval < 0) {
platform_device_put(rtc_platform_device);
return retval;
}
retval = platform_driver_register(&rtc_platform_driver);
if (retval < 0)
platform_device_unregister(rtc_platform_device);
return retval;
}
static void __exit vr41xx_rtc_exit(void)
{
platform_driver_unregister(&rtc_platform_driver);
platform_device_unregister(rtc_platform_device);
}
module_init(vr41xx_rtc_init);
module_exit(vr41xx_rtc_exit);