1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
|
/*
* linux/drivers/rtc/rtc-pl030.c
*
* Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/rtc.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/amba/bus.h>
#include <linux/io.h>
#define RTC_DR (0)
#define RTC_MR (4)
#define RTC_STAT (8)
#define RTC_EOI (8)
#define RTC_LR (12)
#define RTC_CR (16)
#define RTC_CR_MIE (1 << 0)
struct pl030_rtc {
struct rtc_device *rtc;
void __iomem *base;
};
static irqreturn_t pl030_interrupt(int irq, void *dev_id)
{
struct pl030_rtc *rtc = dev_id;
writel(0, rtc->base + RTC_EOI);
return IRQ_HANDLED;
}
static int pl030_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
{
return -ENOIOCTLCMD;
}
static int pl030_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct pl030_rtc *rtc = dev_get_drvdata(dev);
rtc_time_to_tm(readl(rtc->base + RTC_MR), &alrm->time);
return 0;
}
static int pl030_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct pl030_rtc *rtc = dev_get_drvdata(dev);
unsigned long time;
int ret;
/*
* At the moment, we can only deal with non-wildcarded alarm times.
*/
ret = rtc_valid_tm(&alrm->time);
if (ret == 0)
ret = rtc_tm_to_time(&alrm->time, &time);
if (ret == 0)
writel(time, rtc->base + RTC_MR);
return ret;
}
static int pl030_read_time(struct device *dev, struct rtc_time *tm)
{
struct pl030_rtc *rtc = dev_get_drvdata(dev);
rtc_time_to_tm(readl(rtc->base + RTC_DR), tm);
return 0;
}
/*
* Set the RTC time. Unfortunately, we can't accurately set
* the point at which the counter updates.
*
* Also, since RTC_LR is transferred to RTC_CR on next rising
* edge of the 1Hz clock, we must write the time one second
* in advance.
*/
static int pl030_set_time(struct device *dev, struct rtc_time *tm)
{
struct pl030_rtc *rtc = dev_get_drvdata(dev);
unsigned long time;
int ret;
ret = rtc_tm_to_time(tm, &time);
if (ret == 0)
writel(time + 1, rtc->base + RTC_LR);
return ret;
}
static const struct rtc_class_ops pl030_ops = {
.ioctl = pl030_ioctl,
.read_time = pl030_read_time,
.set_time = pl030_set_time,
.read_alarm = pl030_read_alarm,
.set_alarm = pl030_set_alarm,
};
static int pl030_probe(struct amba_device *dev, struct amba_id *id)
{
struct pl030_rtc *rtc;
int ret;
ret = amba_request_regions(dev, NULL);
if (ret)
goto err_req;
rtc = kmalloc(sizeof(*rtc), GFP_KERNEL);
if (!rtc) {
ret = -ENOMEM;
goto err_rtc;
}
rtc->base = ioremap(dev->res.start, SZ_4K);
if (!rtc->base) {
ret = -ENOMEM;
goto err_map;
}
__raw_writel(0, rtc->base + RTC_CR);
__raw_writel(0, rtc->base + RTC_EOI);
amba_set_drvdata(dev, rtc);
ret = request_irq(dev->irq[0], pl030_interrupt, IRQF_DISABLED,
"rtc-pl030", rtc);
if (ret)
goto err_irq;
rtc->rtc = rtc_device_register("pl030", &dev->dev, &pl030_ops,
THIS_MODULE);
if (IS_ERR(rtc->rtc)) {
ret = PTR_ERR(rtc->rtc);
goto err_reg;
}
return 0;
err_reg:
free_irq(dev->irq[0], rtc);
err_irq:
iounmap(rtc->base);
err_map:
kfree(rtc);
err_rtc:
amba_release_regions(dev);
err_req:
return ret;
}
static int pl030_remove(struct amba_device *dev)
{
struct pl030_rtc *rtc = amba_get_drvdata(dev);
amba_set_drvdata(dev, NULL);
writel(0, rtc->base + RTC_CR);
free_irq(dev->irq[0], rtc);
rtc_device_unregister(rtc->rtc);
iounmap(rtc->base);
kfree(rtc);
amba_release_regions(dev);
return 0;
}
static struct amba_id pl030_ids[] = {
{
.id = 0x00041030,
.mask = 0x000fffff,
},
{ 0, 0 },
};
static struct amba_driver pl030_driver = {
.drv = {
.name = "rtc-pl030",
},
.probe = pl030_probe,
.remove = pl030_remove,
.id_table = pl030_ids,
};
static int __init pl030_init(void)
{
return amba_driver_register(&pl030_driver);
}
static void __exit pl030_exit(void)
{
amba_driver_unregister(&pl030_driver);
}
module_init(pl030_init);
module_exit(pl030_exit);
MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
MODULE_DESCRIPTION("ARM AMBA PL030 RTC Driver");
MODULE_LICENSE("GPL");
|
