summaryrefslogtreecommitdiffstats
path: root/drivers/rtc/rtc-ep93xx.c
blob: 5807b77c444a86df3790046ff158f2cb994af244 (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
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
/*
 * 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 <linux/io.h>
#include <linux/gfp.h>

#define EP93XX_RTC_DATA			0x000
#define EP93XX_RTC_MATCH		0x004
#define EP93XX_RTC_STATUS		0x008
#define  EP93XX_RTC_STATUS_INTR		 (1<<0)
#define EP93XX_RTC_LOAD			0x00C
#define EP93XX_RTC_CONTROL		0x010
#define  EP93XX_RTC_CONTROL_MIE		 (1<<0)
#define EP93XX_RTC_SWCOMP		0x108
#define  EP93XX_RTC_SWCOMP_DEL_MASK	 0x001f0000
#define  EP93XX_RTC_SWCOMP_DEL_SHIFT	 16
#define  EP93XX_RTC_SWCOMP_INT_MASK	 0x0000ffff
#define  EP93XX_RTC_SWCOMP_INT_SHIFT	 0

#define DRV_VERSION "0.3"

/*
 * struct device dev.platform_data is used to store our private data
 * because struct rtc_device does not have a variable to hold it.
 */
struct ep93xx_rtc {
	void __iomem	*mmio_base;
	struct rtc_device *rtc;
};

static int ep93xx_rtc_get_swcomp(struct device *dev, unsigned short *preload,
				unsigned short *delete)
{
	struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
	unsigned long comp;

	comp = __raw_readl(ep93xx_rtc->mmio_base + EP93XX_RTC_SWCOMP);

	if (preload)
		*preload = (comp & EP93XX_RTC_SWCOMP_INT_MASK)
				>> EP93XX_RTC_SWCOMP_INT_SHIFT;

	if (delete)
		*delete = (comp & EP93XX_RTC_SWCOMP_DEL_MASK)
				>> EP93XX_RTC_SWCOMP_DEL_SHIFT;

	return 0;
}

static int ep93xx_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
	unsigned long time;

	 time = __raw_readl(ep93xx_rtc->mmio_base + EP93XX_RTC_DATA);

	rtc_time_to_tm(time, tm);
	return 0;
}

static int ep93xx_rtc_set_mmss(struct device *dev, unsigned long secs)
{
	struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;

	__raw_writel(secs + 1, ep93xx_rtc->mmio_base + EP93XX_RTC_LOAD);
	return 0;
}

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

	ep93xx_rtc_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_mmss	= ep93xx_rtc_set_mmss,
	.proc		= ep93xx_rtc_proc,
};

static ssize_t ep93xx_rtc_show_comp_preload(struct device *dev,
			struct device_attribute *attr, char *buf)
{
	unsigned short preload;

	ep93xx_rtc_get_swcomp(dev, &preload, NULL);

	return sprintf(buf, "%d\n", preload);
}
static DEVICE_ATTR(comp_preload, S_IRUGO, ep93xx_rtc_show_comp_preload, NULL);

static ssize_t ep93xx_rtc_show_comp_delete(struct device *dev,
			struct device_attribute *attr, char *buf)
{
	unsigned short delete;

	ep93xx_rtc_get_swcomp(dev, NULL, &delete);

	return sprintf(buf, "%d\n", delete);
}
static DEVICE_ATTR(comp_delete, S_IRUGO, ep93xx_rtc_show_comp_delete, NULL);

static struct attribute *ep93xx_rtc_attrs[] = {
	&dev_attr_comp_preload.attr,
	&dev_attr_comp_delete.attr,
	NULL
};

static const struct attribute_group ep93xx_rtc_sysfs_files = {
	.attrs	= ep93xx_rtc_attrs,
};

static int ep93xx_rtc_probe(struct platform_device *pdev)
{
	struct ep93xx_rtc *ep93xx_rtc;
	struct resource *res;
	int err;

	ep93xx_rtc = devm_kzalloc(&pdev->dev, sizeof(*ep93xx_rtc), GFP_KERNEL);
	if (!ep93xx_rtc)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
		return -ENXIO;

	if (!devm_request_mem_region(&pdev->dev, res->start,
				     resource_size(res), pdev->name))
		return -EBUSY;

	ep93xx_rtc->mmio_base = devm_ioremap(&pdev->dev, res->start,
					     resource_size(res));
	if (!ep93xx_rtc->mmio_base)
		return -ENXIO;

	pdev->dev.platform_data = ep93xx_rtc;
	platform_set_drvdata(pdev, ep93xx_rtc);

	ep93xx_rtc->rtc = devm_rtc_device_register(&pdev->dev,
				pdev->name, &ep93xx_rtc_ops, THIS_MODULE);
	if (IS_ERR(ep93xx_rtc->rtc)) {
		err = PTR_ERR(ep93xx_rtc->rtc);
		goto exit;
	}

	err = sysfs_create_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
	if (err)
		goto exit;

	return 0;

exit:
	platform_set_drvdata(pdev, NULL);
	pdev->dev.platform_data = NULL;
	return err;
}

static int ep93xx_rtc_remove(struct platform_device *pdev)
{
	sysfs_remove_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
	platform_set_drvdata(pdev, NULL);
	pdev->dev.platform_data = NULL;

	return 0;
}

static struct platform_driver ep93xx_rtc_driver = {
	.driver		= {
		.name	= "ep93xx-rtc",
		.owner	= THIS_MODULE,
	},
	.probe		= ep93xx_rtc_probe,
	.remove		= ep93xx_rtc_remove,
};

module_platform_driver(ep93xx_rtc_driver);

MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("EP93XX RTC driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);
MODULE_ALIAS("platform:ep93xx-rtc");