blob: b2d3d20baebc2b07339846929b6d6593e1f821f2 [file] [log] [blame]
Russell Kinga1909012008-04-20 12:08:36 +01001/*
2 * linux/drivers/rtc/rtc-pl030.c
3 *
4 * Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
5 *
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.
9 */
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>
15#include <linux/io.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090016#include <linux/slab.h>
Russell Kinga1909012008-04-20 12:08:36 +010017
18#define RTC_DR (0)
19#define RTC_MR (4)
20#define RTC_STAT (8)
21#define RTC_EOI (8)
22#define RTC_LR (12)
23#define RTC_CR (16)
24#define RTC_CR_MIE (1 << 0)
25
26struct pl030_rtc {
27 struct rtc_device *rtc;
28 void __iomem *base;
29};
30
31static irqreturn_t pl030_interrupt(int irq, void *dev_id)
32{
33 struct pl030_rtc *rtc = dev_id;
34 writel(0, rtc->base + RTC_EOI);
35 return IRQ_HANDLED;
36}
37
Russell Kinga1909012008-04-20 12:08:36 +010038static int pl030_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
39{
40 struct pl030_rtc *rtc = dev_get_drvdata(dev);
41
42 rtc_time_to_tm(readl(rtc->base + RTC_MR), &alrm->time);
43 return 0;
44}
45
46static int pl030_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
47{
48 struct pl030_rtc *rtc = dev_get_drvdata(dev);
49 unsigned long time;
50 int ret;
51
52 /*
53 * At the moment, we can only deal with non-wildcarded alarm times.
54 */
55 ret = rtc_valid_tm(&alrm->time);
56 if (ret == 0)
57 ret = rtc_tm_to_time(&alrm->time, &time);
58 if (ret == 0)
59 writel(time, rtc->base + RTC_MR);
60 return ret;
61}
62
63static int pl030_read_time(struct device *dev, struct rtc_time *tm)
64{
65 struct pl030_rtc *rtc = dev_get_drvdata(dev);
66
67 rtc_time_to_tm(readl(rtc->base + RTC_DR), tm);
68
69 return 0;
70}
71
72/*
73 * Set the RTC time. Unfortunately, we can't accurately set
74 * the point at which the counter updates.
75 *
76 * Also, since RTC_LR is transferred to RTC_CR on next rising
77 * edge of the 1Hz clock, we must write the time one second
78 * in advance.
79 */
80static int pl030_set_time(struct device *dev, struct rtc_time *tm)
81{
82 struct pl030_rtc *rtc = dev_get_drvdata(dev);
83 unsigned long time;
84 int ret;
85
86 ret = rtc_tm_to_time(tm, &time);
87 if (ret == 0)
88 writel(time + 1, rtc->base + RTC_LR);
89
90 return ret;
91}
92
93static const struct rtc_class_ops pl030_ops = {
Russell Kinga1909012008-04-20 12:08:36 +010094 .read_time = pl030_read_time,
95 .set_time = pl030_set_time,
96 .read_alarm = pl030_read_alarm,
97 .set_alarm = pl030_set_alarm,
98};
99
Russell Kingaa25afa2011-02-19 15:55:00 +0000100static int pl030_probe(struct amba_device *dev, const struct amba_id *id)
Russell Kinga1909012008-04-20 12:08:36 +0100101{
102 struct pl030_rtc *rtc;
103 int ret;
104
105 ret = amba_request_regions(dev, NULL);
106 if (ret)
107 goto err_req;
108
109 rtc = kmalloc(sizeof(*rtc), GFP_KERNEL);
110 if (!rtc) {
111 ret = -ENOMEM;
112 goto err_rtc;
113 }
114
Linus Walleijdc890c22009-06-07 23:27:31 +0100115 rtc->base = ioremap(dev->res.start, resource_size(&dev->res));
Russell Kinga1909012008-04-20 12:08:36 +0100116 if (!rtc->base) {
117 ret = -ENOMEM;
118 goto err_map;
119 }
120
121 __raw_writel(0, rtc->base + RTC_CR);
122 __raw_writel(0, rtc->base + RTC_EOI);
123
124 amba_set_drvdata(dev, rtc);
125
126 ret = request_irq(dev->irq[0], pl030_interrupt, IRQF_DISABLED,
127 "rtc-pl030", rtc);
128 if (ret)
129 goto err_irq;
130
131 rtc->rtc = rtc_device_register("pl030", &dev->dev, &pl030_ops,
132 THIS_MODULE);
133 if (IS_ERR(rtc->rtc)) {
134 ret = PTR_ERR(rtc->rtc);
135 goto err_reg;
136 }
137
138 return 0;
139
140 err_reg:
141 free_irq(dev->irq[0], rtc);
142 err_irq:
143 iounmap(rtc->base);
144 err_map:
145 kfree(rtc);
146 err_rtc:
147 amba_release_regions(dev);
148 err_req:
149 return ret;
150}
151
152static int pl030_remove(struct amba_device *dev)
153{
154 struct pl030_rtc *rtc = amba_get_drvdata(dev);
155
156 amba_set_drvdata(dev, NULL);
157
158 writel(0, rtc->base + RTC_CR);
159
160 free_irq(dev->irq[0], rtc);
161 rtc_device_unregister(rtc->rtc);
162 iounmap(rtc->base);
163 kfree(rtc);
164 amba_release_regions(dev);
165
166 return 0;
167}
168
169static struct amba_id pl030_ids[] = {
170 {
171 .id = 0x00041030,
172 .mask = 0x000fffff,
173 },
174 { 0, 0 },
175};
176
Dave Martin66bce592011-10-05 15:15:21 +0100177MODULE_DEVICE_TABLE(amba, pl030_ids);
178
Russell Kinga1909012008-04-20 12:08:36 +0100179static struct amba_driver pl030_driver = {
180 .drv = {
181 .name = "rtc-pl030",
182 },
183 .probe = pl030_probe,
184 .remove = pl030_remove,
185 .id_table = pl030_ids,
186};
187
viresh kumar9e5ed092012-03-15 10:40:38 +0100188module_amba_driver(pl030_driver);
Russell Kinga1909012008-04-20 12:08:36 +0100189
190MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
191MODULE_DESCRIPTION("ARM AMBA PL030 RTC Driver");
192MODULE_LICENSE("GPL");