aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/rtc/rtc-ep93xx.c
blob: 1e99325270df8e99263b1c7d930854180b3cf960 (plain)
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
/*
 * A driver for the RTC embedded in the Cirrus Logic EP93XX processors
 * Copyright (c) 2006 Tower Technologies
 *
 * Author: Alessandro Zummo <a.zummo@towertech.it>
 *
 * 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/platform_device.h>
#include <asm/hardware.h>

#define EP93XX_RTC_REG(x)	(EP93XX_RTC_BASE + (x))
#define EP93XX_RTC_DATA		EP93XX_RTC_REG(0x0000)
#define EP93XX_RTC_LOAD		EP93XX_RTC_REG(0x000C)
#define EP93XX_RTC_SWCOMP	EP93XX_RTC_REG(0x0108)

#define DRV_VERSION "0.2"

static int ep93xx_get_swcomp(struct device *dev, unsigned short *preload,
				unsigned short *delete)
{
	unsigned short comp = __raw_readl(EP93XX_RTC_SWCOMP);

	if (preload)
		*preload = comp & 0xffff;

	if (delete)
		*delete = (comp >> 16) & 0x1f;

	return 0;
}

static int ep93xx_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	unsigned long time = __raw_readl(EP93XX_RTC_DATA);

	rtc_time_to_tm(time, tm);
	return 0;
}

static int ep93xx_rtc_set_mmss(struct device *dev, unsigned long secs)
{
	__raw_writel(secs + 1, EP93XX_RTC_LOAD);
	return 0;
}

static int ep93xx_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	int err;
	unsigned long secs;

	err = rtc_tm_to_time(tm, &secs);
	if (err != 0)
		return err;

	return ep93xx_rtc_set_mmss(dev, secs);
}

static int ep93xx_rtc_proc(struct device *dev, struct seq_file *seq)
{
	unsigned short preload, delete;

	ep93xx_get_swcomp(dev, &preload, &delete);

	seq_printf(seq, "preload\t\t: %d\n", preload);
	seq_printf(seq, "delete\t\t: %d\n", delete);

	return 0;
}

static const struct rtc_class_ops ep93xx_rtc_ops = {
	.read_time	= ep93xx_rtc_read_time,
	.set_time	= ep93xx_rtc_set_time,
	.set_mmss	= ep93xx_rtc_set_mmss,
	.proc		= ep93xx_rtc_proc,
};

static ssize_t ep93xx_sysfs_show_comp_preload(struct device *dev,
			struct device_attribute *attr, char *buf)
{
	unsigned short preload;

	ep93xx_get_swcomp(dev, &preload, NULL);

	return sprintf(buf, "%d\n", preload);
}
static DEVICE_ATTR(comp_preload, S_IRUGO, ep93xx_sysfs_show_comp_preload, NULL);

static ssize_t ep93xx_sysfs_show_comp_delete(struct device *dev,
			struct device_attribute *attr, char *buf)
{
	unsigned short delete;

	ep93xx_get_swcomp(dev, NULL, &delete);

	return sprintf(buf, "%d\n", delete);
}
static DEVICE_ATTR(comp_delete, S_IRUGO, ep93xx_sysfs_show_comp_delete, NULL);


static int __devinit ep93xx_rtc_probe(struct platform_device *dev)
{
	struct rtc_device *rtc = rtc_device_register("ep93xx",
				&dev->dev, &ep93xx_rtc_ops, THIS_MODULE);

	if (IS_ERR(rtc)) {
		return PTR_ERR(rtc);
	}

	platform_set_drvdata(dev, rtc);

	device_create_file(&dev->dev, &dev_attr_comp_preload);
	device_create_file(&dev->dev, &dev_attr_comp_delete);

	return 0;
}

static int __devexit ep93xx_rtc_remove(struct platform_device *dev)
{
	struct rtc_device *rtc = platform_get_drvdata(dev);

 	if (rtc)
		rtc_device_unregister(rtc);

	platform_set_drvdata(dev, NULL);

	return 0;
}

/* work with hotplug and coldplug */
MODULE_ALIAS("platform:ep93xx-rtc");

static struct platform_driver ep93xx_rtc_platform_driver = {
	.driver		= {
		.name	= "ep93xx-rtc",
		.owner	= THIS_MODULE,
	},
	.probe		= ep93xx_rtc_probe,
	.remove		= __devexit_p(ep93xx_rtc_remove),
};

static int __init ep93xx_rtc_init(void)
{
	return platform_driver_register(&ep93xx_rtc_platform_driver);
}

static void __exit ep93xx_rtc_exit(void)
{
	platform_driver_unregister(&ep93xx_rtc_platform_driver);
}

MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("EP93XX RTC driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);

module_init(ep93xx_rtc_init);
module_exit(ep93xx_rtc_exit);