2 * linux/drivers/rtc/rtc-pl030.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/rtc.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/amba/bus.h>
23 #define RTC_CR_MIE (1 << 0)
26 struct rtc_device *rtc;
30 static irqreturn_t pl030_interrupt(int irq, void *dev_id)
32 struct pl030_rtc *rtc = dev_id;
33 writel(0, rtc->base + RTC_EOI);
37 static int pl030_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
42 static int pl030_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
44 struct pl030_rtc *rtc = dev_get_drvdata(dev);
46 rtc_time_to_tm(readl(rtc->base + RTC_MR), &alrm->time);
50 static int pl030_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
52 struct pl030_rtc *rtc = dev_get_drvdata(dev);
57 * At the moment, we can only deal with non-wildcarded alarm times.
59 ret = rtc_valid_tm(&alrm->time);
61 ret = rtc_tm_to_time(&alrm->time, &time);
63 writel(time, rtc->base + RTC_MR);
67 static int pl030_read_time(struct device *dev, struct rtc_time *tm)
69 struct pl030_rtc *rtc = dev_get_drvdata(dev);
71 rtc_time_to_tm(readl(rtc->base + RTC_DR), tm);
77 * Set the RTC time. Unfortunately, we can't accurately set
78 * the point at which the counter updates.
80 * Also, since RTC_LR is transferred to RTC_CR on next rising
81 * edge of the 1Hz clock, we must write the time one second
84 static int pl030_set_time(struct device *dev, struct rtc_time *tm)
86 struct pl030_rtc *rtc = dev_get_drvdata(dev);
90 ret = rtc_tm_to_time(tm, &time);
92 writel(time + 1, rtc->base + RTC_LR);
97 static const struct rtc_class_ops pl030_ops = {
99 .read_time = pl030_read_time,
100 .set_time = pl030_set_time,
101 .read_alarm = pl030_read_alarm,
102 .set_alarm = pl030_set_alarm,
105 static int pl030_probe(struct amba_device *dev, void *id)
107 struct pl030_rtc *rtc;
110 ret = amba_request_regions(dev, NULL);
114 rtc = kmalloc(sizeof(*rtc), GFP_KERNEL);
120 rtc->base = ioremap(dev->res.start, SZ_4K);
126 __raw_writel(0, rtc->base + RTC_CR);
127 __raw_writel(0, rtc->base + RTC_EOI);
129 amba_set_drvdata(dev, rtc);
131 ret = request_irq(dev->irq[0], pl030_interrupt, IRQF_DISABLED,
136 rtc->rtc = rtc_device_register("pl030", &dev->dev, &pl030_ops,
138 if (IS_ERR(rtc->rtc)) {
139 ret = PTR_ERR(rtc->rtc);
146 free_irq(dev->irq[0], rtc);
152 amba_release_regions(dev);
157 static int pl030_remove(struct amba_device *dev)
159 struct pl030_rtc *rtc = amba_get_drvdata(dev);
161 amba_set_drvdata(dev, NULL);
163 writel(0, rtc->base + RTC_CR);
165 free_irq(dev->irq[0], rtc);
166 rtc_device_unregister(rtc->rtc);
169 amba_release_regions(dev);
174 static struct amba_id pl030_ids[] = {
182 static struct amba_driver pl030_driver = {
186 .probe = pl030_probe,
187 .remove = pl030_remove,
188 .id_table = pl030_ids,
191 static int __init pl030_init(void)
193 return amba_driver_register(&pl030_driver);
196 static void __exit pl030_exit(void)
198 amba_driver_unregister(&pl030_driver);
201 module_init(pl030_init);
202 module_exit(pl030_exit);
204 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
205 MODULE_DESCRIPTION("ARM AMBA PL030 RTC Driver");
206 MODULE_LICENSE("GPL");