linux/drivers/rtc/rtc-sh.c
Paul Mundt 317a6104a9 rtc: New RTC driver for SuperH On-Chip RTC.
This replaces the old SH RTC driver, and allows us to
clean quite a lot of things up on the board-specific
side.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2006-09-27 17:13:19 +09:00

468 lines
11 KiB
C

/*
* SuperH On-Chip RTC Support
*
* Copyright (C) 2006 Paul Mundt
*
* Based on the old arch/sh/kernel/cpu/rtc.c by:
*
* Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
* Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/bcd.h>
#include <linux/rtc.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <asm/io.h>
#ifdef CONFIG_CPU_SH3
#define rtc_reg_size sizeof(u16)
#define RTC_BIT_INVERTED 0 /* No bug on SH7708, SH7709A */
#elif defined(CONFIG_CPU_SH4)
#define rtc_reg_size sizeof(u32)
#define RTC_BIT_INVERTED 0x40 /* bug on SH7750, SH7750S */
#endif
#define RTC_REG(r) ((r) * rtc_reg_size)
#define R64CNT RTC_REG(0)
#define RSECCNT RTC_REG(1)
#define RMINCNT RTC_REG(2)
#define RHRCNT RTC_REG(3)
#define RWKCNT RTC_REG(4)
#define RDAYCNT RTC_REG(5)
#define RMONCNT RTC_REG(6)
#define RYRCNT RTC_REG(7)
#define RSECAR RTC_REG(8)
#define RMINAR RTC_REG(9)
#define RHRAR RTC_REG(10)
#define RWKAR RTC_REG(11)
#define RDAYAR RTC_REG(12)
#define RMONAR RTC_REG(13)
#define RCR1 RTC_REG(14)
#define RCR2 RTC_REG(15)
/* RCR1 Bits */
#define RCR1_CF 0x80 /* Carry Flag */
#define RCR1_CIE 0x10 /* Carry Interrupt Enable */
#define RCR1_AIE 0x08 /* Alarm Interrupt Enable */
#define RCR1_AF 0x01 /* Alarm Flag */
/* RCR2 Bits */
#define RCR2_PEF 0x80 /* PEriodic interrupt Flag */
#define RCR2_PESMASK 0x70 /* Periodic interrupt Set */
#define RCR2_RTCEN 0x08 /* ENable RTC */
#define RCR2_ADJ 0x04 /* ADJustment (30-second) */
#define RCR2_RESET 0x02 /* Reset bit */
#define RCR2_START 0x01 /* Start bit */
struct sh_rtc {
void __iomem *regbase;
unsigned long regsize;
struct resource *res;
unsigned int alarm_irq, periodic_irq, carry_irq;
struct rtc_device *rtc_dev;
spinlock_t lock;
};
static irqreturn_t sh_rtc_interrupt(int irq, void *id, struct pt_regs *regs)
{
struct platform_device *pdev = id;
struct sh_rtc *rtc = platform_get_drvdata(pdev);
unsigned int tmp, events = 0;
spin_lock(&rtc->lock);
tmp = readb(rtc->regbase + RCR1);
if (tmp & RCR1_AF)
events |= RTC_AF | RTC_IRQF;
tmp &= ~(RCR1_CF | RCR1_AF);
writeb(tmp, rtc->regbase + RCR1);
rtc_update_irq(&rtc->rtc_dev->class_dev, 1, events);
spin_unlock(&rtc->lock);
return IRQ_HANDLED;
}
static irqreturn_t sh_rtc_periodic(int irq, void *id, struct pt_regs *regs)
{
struct sh_rtc *rtc = dev_get_drvdata(id);
spin_lock(&rtc->lock);
rtc_update_irq(&rtc->rtc_dev->class_dev, 1, RTC_PF | RTC_IRQF);
spin_unlock(&rtc->lock);
return IRQ_HANDLED;
}
static inline void sh_rtc_setpie(struct device *dev, unsigned int enable)
{
struct sh_rtc *rtc = dev_get_drvdata(dev);
unsigned int tmp;
spin_lock_irq(&rtc->lock);
tmp = readb(rtc->regbase + RCR2);
if (enable) {
tmp &= ~RCR2_PESMASK;
tmp |= RCR2_PEF | (2 << 4);
} else
tmp &= ~(RCR2_PESMASK | RCR2_PEF);
writeb(tmp, rtc->regbase + RCR2);
spin_unlock_irq(&rtc->lock);
}
static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
{
struct sh_rtc *rtc = dev_get_drvdata(dev);
unsigned int tmp;
spin_lock_irq(&rtc->lock);
tmp = readb(rtc->regbase + RCR1);
if (enable)
tmp |= RCR1_AIE;
else
tmp &= ~RCR1_AIE;
writeb(tmp, rtc->regbase + RCR1);
spin_unlock_irq(&rtc->lock);
}
static int sh_rtc_open(struct device *dev)
{
struct sh_rtc *rtc = dev_get_drvdata(dev);
unsigned int tmp;
int ret;
tmp = readb(rtc->regbase + RCR1);
tmp &= ~RCR1_CF;
tmp |= RCR1_CIE;
writeb(tmp, rtc->regbase + RCR1);
ret = request_irq(rtc->periodic_irq, sh_rtc_periodic, SA_INTERRUPT,
"sh-rtc period", dev);
if (unlikely(ret)) {
dev_err(dev, "request period IRQ failed with %d, IRQ %d\n",
ret, rtc->periodic_irq);
return ret;
}
ret = request_irq(rtc->carry_irq, sh_rtc_interrupt, SA_INTERRUPT,
"sh-rtc carry", dev);
if (unlikely(ret)) {
dev_err(dev, "request carry IRQ failed with %d, IRQ %d\n",
ret, rtc->carry_irq);
free_irq(rtc->periodic_irq, dev);
goto err_bad_carry;
}
ret = request_irq(rtc->alarm_irq, sh_rtc_interrupt, SA_INTERRUPT,
"sh-rtc alarm", dev);
if (unlikely(ret)) {
dev_err(dev, "request alarm IRQ failed with %d, IRQ %d\n",
ret, rtc->alarm_irq);
goto err_bad_alarm;
}
return 0;
err_bad_alarm:
free_irq(rtc->carry_irq, dev);
err_bad_carry:
free_irq(rtc->periodic_irq, dev);
return ret;
}
static void sh_rtc_release(struct device *dev)
{
struct sh_rtc *rtc = dev_get_drvdata(dev);
sh_rtc_setpie(dev, 0);
free_irq(rtc->periodic_irq, dev);
free_irq(rtc->carry_irq, dev);
free_irq(rtc->alarm_irq, dev);
}
static int sh_rtc_proc(struct device *dev, struct seq_file *seq)
{
struct sh_rtc *rtc = dev_get_drvdata(dev);
unsigned int tmp;
tmp = readb(rtc->regbase + RCR1);
seq_printf(seq, "alarm_IRQ\t: %s\n",
(tmp & RCR1_AIE) ? "yes" : "no");
seq_printf(seq, "carry_IRQ\t: %s\n",
(tmp & RCR1_CIE) ? "yes" : "no");
tmp = readb(rtc->regbase + RCR2);
seq_printf(seq, "periodic_IRQ\t: %s\n",
(tmp & RCR2_PEF) ? "yes" : "no");
return 0;
}
static int sh_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
{
unsigned int ret = -ENOIOCTLCMD;
switch (cmd) {
case RTC_PIE_OFF:
case RTC_PIE_ON:
sh_rtc_setpie(dev, cmd == RTC_PIE_ON);
ret = 0;
break;
case RTC_AIE_OFF:
case RTC_AIE_ON:
sh_rtc_setaie(dev, cmd == RTC_AIE_ON);
ret = 0;
break;
}
return ret;
}
static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct platform_device *pdev = to_platform_device(dev);
struct sh_rtc *rtc = platform_get_drvdata(pdev);
unsigned int sec128, sec2, yr, yr100, cf_bit;
do {
unsigned int tmp;
spin_lock_irq(&rtc->lock);
tmp = readb(rtc->regbase + RCR1);
tmp &= ~RCR1_CF; /* Clear CF-bit */
tmp |= RCR1_CIE;
writeb(tmp, rtc->regbase + RCR1);
sec128 = readb(rtc->regbase + R64CNT);
tm->tm_sec = BCD2BIN(readb(rtc->regbase + RSECCNT));
tm->tm_min = BCD2BIN(readb(rtc->regbase + RMINCNT));
tm->tm_hour = BCD2BIN(readb(rtc->regbase + RHRCNT));
tm->tm_wday = BCD2BIN(readb(rtc->regbase + RWKCNT));
tm->tm_mday = BCD2BIN(readb(rtc->regbase + RDAYCNT));
tm->tm_mon = BCD2BIN(readb(rtc->regbase + RMONCNT));
#if defined(CONFIG_CPU_SH4)
yr = readw(rtc->regbase + RYRCNT);
yr100 = BCD2BIN(yr >> 8);
yr &= 0xff;
#else
yr = readb(rtc->regbase + RYRCNT);
yr100 = BCD2BIN((yr == 0x99) ? 0x19 : 0x20);
#endif
tm->tm_year = (yr100 * 100 + BCD2BIN(yr)) - 1900;
sec2 = readb(rtc->regbase + R64CNT);
cf_bit = readb(rtc->regbase + RCR1) & RCR1_CF;
spin_unlock_irq(&rtc->lock);
} while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0);
#if RTC_BIT_INVERTED != 0
if ((sec128 & RTC_BIT_INVERTED))
tm->tm_sec--;
#endif
dev_dbg(&dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
"mday=%d, mon=%d, year=%d, wday=%d\n",
__FUNCTION__,
tm->tm_sec, tm->tm_min, tm->tm_hour,
tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
if (rtc_valid_tm(tm) < 0)
dev_err(dev, "invalid date\n");
return 0;
}
static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct platform_device *pdev = to_platform_device(dev);
struct sh_rtc *rtc = platform_get_drvdata(pdev);
unsigned int tmp;
int year;
spin_lock_irq(&rtc->lock);
/* Reset pre-scaler & stop RTC */
tmp = readb(rtc->regbase + RCR2);
tmp |= RCR2_RESET;
writeb(tmp, rtc->regbase + RCR2);
writeb(BIN2BCD(tm->tm_sec), rtc->regbase + RSECCNT);
writeb(BIN2BCD(tm->tm_min), rtc->regbase + RMINCNT);
writeb(BIN2BCD(tm->tm_hour), rtc->regbase + RHRCNT);
writeb(BIN2BCD(tm->tm_wday), rtc->regbase + RWKCNT);
writeb(BIN2BCD(tm->tm_mday), rtc->regbase + RDAYCNT);
writeb(BIN2BCD(tm->tm_mon), rtc->regbase + RMONCNT);
#ifdef CONFIG_CPU_SH3
year = tm->tm_year % 100;
writeb(BIN2BCD(year), rtc->regbase + RYRCNT);
#else
year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) |
BIN2BCD(tm->tm_year % 100);
writew(year, rtc->regbase + RYRCNT);
#endif
/* Start RTC */
tmp = readb(rtc->regbase + RCR2);
tmp &= ~RCR2_RESET;
tmp |= RCR2_RTCEN | RCR2_START;
writeb(tmp, rtc->regbase + RCR2);
spin_unlock_irq(&rtc->lock);
return 0;
}
static struct rtc_class_ops sh_rtc_ops = {
.open = sh_rtc_open,
.release = sh_rtc_release,
.ioctl = sh_rtc_ioctl,
.read_time = sh_rtc_read_time,
.set_time = sh_rtc_set_time,
.proc = sh_rtc_proc,
};
static int __devinit sh_rtc_probe(struct platform_device *pdev)
{
struct sh_rtc *rtc;
struct resource *res;
int ret = -ENOENT;
rtc = kzalloc(sizeof(struct sh_rtc), GFP_KERNEL);
if (unlikely(!rtc))
return -ENOMEM;
spin_lock_init(&rtc->lock);
rtc->periodic_irq = platform_get_irq(pdev, 0);
if (unlikely(rtc->periodic_irq < 0)) {
dev_err(&pdev->dev, "No IRQ for period\n");
goto err_badres;
}
rtc->carry_irq = platform_get_irq(pdev, 1);
if (unlikely(rtc->carry_irq < 0)) {
dev_err(&pdev->dev, "No IRQ for carry\n");
goto err_badres;
}
rtc->alarm_irq = platform_get_irq(pdev, 2);
if (unlikely(rtc->alarm_irq < 0)) {
dev_err(&pdev->dev, "No IRQ for alarm\n");
goto err_badres;
}
res = platform_get_resource(pdev, IORESOURCE_IO, 0);
if (unlikely(res == NULL)) {
dev_err(&pdev->dev, "No IO resource\n");
goto err_badres;
}
rtc->regsize = res->end - res->start + 1;
rtc->res = request_mem_region(res->start, rtc->regsize, pdev->name);
if (unlikely(!rtc->res)) {
ret = -EBUSY;
goto err_badres;
}
rtc->regbase = (void __iomem *)rtc->res->start;
if (unlikely(!rtc->regbase)) {
ret = -EINVAL;
goto err_badmap;
}
rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
&sh_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc)) {
ret = PTR_ERR(rtc->rtc_dev);
goto err_badmap;
}
platform_set_drvdata(pdev, rtc);
return 0;
err_badmap:
release_resource(rtc->res);
err_badres:
kfree(rtc);
return ret;
}
static int __devexit sh_rtc_remove(struct platform_device *pdev)
{
struct sh_rtc *rtc = platform_get_drvdata(pdev);
if (likely(rtc->rtc_dev))
rtc_device_unregister(rtc->rtc_dev);
sh_rtc_setpie(&pdev->dev, 0);
sh_rtc_setaie(&pdev->dev, 0);
release_resource(rtc->res);
platform_set_drvdata(pdev, NULL);
kfree(rtc);
return 0;
}
static struct platform_driver sh_rtc_platform_driver = {
.driver = {
.name = "sh-rtc",
.owner = THIS_MODULE,
},
.probe = sh_rtc_probe,
.remove = __devexit_p(sh_rtc_remove),
};
static int __init sh_rtc_init(void)
{
return platform_driver_register(&sh_rtc_platform_driver);
}
static void __exit sh_rtc_exit(void)
{
platform_driver_unregister(&sh_rtc_platform_driver);
}
module_init(sh_rtc_init);
module_exit(sh_rtc_exit);
MODULE_DESCRIPTION("SuperH on-chip RTC driver");
MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
MODULE_LICENSE("GPL");