2 * linux/arch/arm/mach-integrator/time.c
4 * Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/time.h>
13 #include <linux/mc146818rtc.h>
14 #include <linux/interrupt.h>
15 #include <linux/init.h>
16 #include <linux/device.h>
18 #include <asm/hardware/amba.h>
19 #include <asm/hardware.h>
21 #include <asm/uaccess.h>
24 #include <asm/mach/time.h>
32 #define RTC_CR_MIE (1 << 0)
34 extern int (*set_rtc)(void);
35 static void __iomem *rtc_base;
37 static int integrator_set_rtc(void)
39 __raw_writel(xtime.tv_sec, rtc_base + RTC_LR);
43 static void rtc_read_alarm(struct rtc_wkalrm *alrm)
45 rtc_time_to_tm(readl(rtc_base + RTC_MR), &alrm->time);
48 static int rtc_set_alarm(struct rtc_wkalrm *alrm)
53 ret = rtc_tm_to_time(&alrm->time, &time);
55 writel(time, rtc_base + RTC_MR);
59 static void rtc_read_time(struct rtc_time *tm)
61 rtc_time_to_tm(readl(rtc_base + RTC_DR), tm);
65 * Set the RTC time. Unfortunately, we can't accurately set
66 * the point at which the counter updates.
68 * Also, since RTC_LR is transferred to RTC_CR on next rising
69 * edge of the 1Hz clock, we must write the time one second
72 static int rtc_set_time(struct rtc_time *tm)
77 ret = rtc_tm_to_time(tm, &time);
79 writel(time + 1, rtc_base + RTC_LR);
84 static struct rtc_ops rtc_ops = {
86 .read_time = rtc_read_time,
87 .set_time = rtc_set_time,
88 .read_alarm = rtc_read_alarm,
89 .set_alarm = rtc_set_alarm,
92 static irqreturn_t rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
94 writel(0, rtc_base + RTC_EOI);
98 static int rtc_probe(struct amba_device *dev, void *id)
105 ret = amba_request_regions(dev, NULL);
109 rtc_base = ioremap(dev->res.start, SZ_4K);
115 __raw_writel(0, rtc_base + RTC_CR);
116 __raw_writel(0, rtc_base + RTC_EOI);
118 xtime.tv_sec = __raw_readl(rtc_base + RTC_DR);
120 ret = request_irq(dev->irq[0], rtc_interrupt, SA_INTERRUPT,
125 ret = register_rtc(&rtc_ops);
129 set_rtc = integrator_set_rtc;
133 free_irq(dev->irq[0], dev);
138 amba_release_regions(dev);
143 static int rtc_remove(struct amba_device *dev)
147 writel(0, rtc_base + RTC_CR);
149 free_irq(dev->irq[0], dev);
150 unregister_rtc(&rtc_ops);
154 amba_release_regions(dev);
159 static struct timespec rtc_delta;
161 static int rtc_suspend(struct amba_device *dev, pm_message_t state)
165 rtc.tv_sec = readl(rtc_base + RTC_DR);
167 save_time_delta(&rtc_delta, &rtc);
172 static int rtc_resume(struct amba_device *dev)
176 rtc.tv_sec = readl(rtc_base + RTC_DR);
178 restore_time_delta(&rtc_delta, &rtc);
183 static struct amba_id rtc_ids[] = {
191 static struct amba_driver rtc_driver = {
196 .remove = rtc_remove,
197 .suspend = rtc_suspend,
198 .resume = rtc_resume,
202 static int __init integrator_rtc_init(void)
204 return amba_driver_register(&rtc_driver);
207 static void __exit integrator_rtc_exit(void)
209 amba_driver_unregister(&rtc_driver);
212 module_init(integrator_rtc_init);
213 module_exit(integrator_rtc_exit);