Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6.git] / drivers / rtc / rtc-ep93xx.c
1 /*
2  * A driver for the RTC embedded in the Cirrus Logic EP93XX processors
3  * Copyright (c) 2006 Tower Technologies
4  *
5  * Author: Alessandro Zummo <a.zummo@towertech.it>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11
12 #include <linux/module.h>
13 #include <linux/rtc.h>
14 #include <linux/platform_device.h>
15 #include <linux/io.h>
16
17 #define EP93XX_RTC_DATA                 0x000
18 #define EP93XX_RTC_MATCH                0x004
19 #define EP93XX_RTC_STATUS               0x008
20 #define  EP93XX_RTC_STATUS_INTR          (1<<0)
21 #define EP93XX_RTC_LOAD                 0x00C
22 #define EP93XX_RTC_CONTROL              0x010
23 #define  EP93XX_RTC_CONTROL_MIE          (1<<0)
24 #define EP93XX_RTC_SWCOMP               0x108
25 #define  EP93XX_RTC_SWCOMP_DEL_MASK      0x001f0000
26 #define  EP93XX_RTC_SWCOMP_DEL_SHIFT     16
27 #define  EP93XX_RTC_SWCOMP_INT_MASK      0x0000ffff
28 #define  EP93XX_RTC_SWCOMP_INT_SHIFT     0
29
30 #define DRV_VERSION "0.3"
31
32 /*
33  * struct device dev.platform_data is used to store our private data
34  * because struct rtc_device does not have a variable to hold it.
35  */
36 struct ep93xx_rtc {
37         void __iomem    *mmio_base;
38 };
39
40 static int ep93xx_rtc_get_swcomp(struct device *dev, unsigned short *preload,
41                                 unsigned short *delete)
42 {
43         struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
44         unsigned long comp;
45
46         comp = __raw_readl(ep93xx_rtc->mmio_base + EP93XX_RTC_SWCOMP);
47
48         if (preload)
49                 *preload = (comp & EP93XX_RTC_SWCOMP_INT_MASK)
50                                 >> EP93XX_RTC_SWCOMP_INT_SHIFT;
51
52         if (delete)
53                 *delete = (comp & EP93XX_RTC_SWCOMP_DEL_MASK)
54                                 >> EP93XX_RTC_SWCOMP_DEL_SHIFT;
55
56         return 0;
57 }
58
59 static int ep93xx_rtc_read_time(struct device *dev, struct rtc_time *tm)
60 {
61         struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
62         unsigned long time;
63
64          time = __raw_readl(ep93xx_rtc->mmio_base + EP93XX_RTC_DATA);
65
66         rtc_time_to_tm(time, tm);
67         return 0;
68 }
69
70 static int ep93xx_rtc_set_mmss(struct device *dev, unsigned long secs)
71 {
72         struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
73
74         __raw_writel(secs + 1, ep93xx_rtc->mmio_base + EP93XX_RTC_LOAD);
75         return 0;
76 }
77
78 static int ep93xx_rtc_proc(struct device *dev, struct seq_file *seq)
79 {
80         unsigned short preload, delete;
81
82         ep93xx_rtc_get_swcomp(dev, &preload, &delete);
83
84         seq_printf(seq, "preload\t\t: %d\n", preload);
85         seq_printf(seq, "delete\t\t: %d\n", delete);
86
87         return 0;
88 }
89
90 static const struct rtc_class_ops ep93xx_rtc_ops = {
91         .read_time      = ep93xx_rtc_read_time,
92         .set_mmss       = ep93xx_rtc_set_mmss,
93         .proc           = ep93xx_rtc_proc,
94 };
95
96 static ssize_t ep93xx_rtc_show_comp_preload(struct device *dev,
97                         struct device_attribute *attr, char *buf)
98 {
99         unsigned short preload;
100
101         ep93xx_rtc_get_swcomp(dev, &preload, NULL);
102
103         return sprintf(buf, "%d\n", preload);
104 }
105 static DEVICE_ATTR(comp_preload, S_IRUGO, ep93xx_rtc_show_comp_preload, NULL);
106
107 static ssize_t ep93xx_rtc_show_comp_delete(struct device *dev,
108                         struct device_attribute *attr, char *buf)
109 {
110         unsigned short delete;
111
112         ep93xx_rtc_get_swcomp(dev, NULL, &delete);
113
114         return sprintf(buf, "%d\n", delete);
115 }
116 static DEVICE_ATTR(comp_delete, S_IRUGO, ep93xx_rtc_show_comp_delete, NULL);
117
118 static struct attribute *ep93xx_rtc_attrs[] = {
119         &dev_attr_comp_preload.attr,
120         &dev_attr_comp_delete.attr,
121         NULL
122 };
123
124 static const struct attribute_group ep93xx_rtc_sysfs_files = {
125         .attrs  = ep93xx_rtc_attrs,
126 };
127
128 static int __init ep93xx_rtc_probe(struct platform_device *pdev)
129 {
130         struct ep93xx_rtc *ep93xx_rtc;
131         struct resource *res;
132         struct rtc_device *rtc;
133         int err;
134
135         ep93xx_rtc = devm_kzalloc(&pdev->dev, sizeof(*ep93xx_rtc), GFP_KERNEL);
136         if (!ep93xx_rtc)
137                 return -ENOMEM;
138
139         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
140         if (!res)
141                 return -ENXIO;
142
143         if (!devm_request_mem_region(&pdev->dev, res->start,
144                                      resource_size(res), pdev->name))
145                 return -EBUSY;
146
147         ep93xx_rtc->mmio_base = devm_ioremap(&pdev->dev, res->start,
148                                              resource_size(res));
149         if (!ep93xx_rtc->mmio_base)
150                 return -ENXIO;
151
152         pdev->dev.platform_data = ep93xx_rtc;
153
154         rtc = rtc_device_register(pdev->name,
155                                 &pdev->dev, &ep93xx_rtc_ops, THIS_MODULE);
156         if (IS_ERR(rtc)) {
157                 err = PTR_ERR(rtc);
158                 goto exit;
159         }
160
161         platform_set_drvdata(pdev, rtc);
162
163         err = sysfs_create_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
164         if (err)
165                 goto fail;
166
167         return 0;
168
169 fail:
170         platform_set_drvdata(pdev, NULL);
171         rtc_device_unregister(rtc);
172 exit:
173         pdev->dev.platform_data = NULL;
174         return err;
175 }
176
177 static int __exit ep93xx_rtc_remove(struct platform_device *pdev)
178 {
179         struct rtc_device *rtc = platform_get_drvdata(pdev);
180
181         sysfs_remove_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
182         platform_set_drvdata(pdev, NULL);
183         rtc_device_unregister(rtc);
184         pdev->dev.platform_data = NULL;
185
186         return 0;
187 }
188
189 /* work with hotplug and coldplug */
190 MODULE_ALIAS("platform:ep93xx-rtc");
191
192 static struct platform_driver ep93xx_rtc_driver = {
193         .driver         = {
194                 .name   = "ep93xx-rtc",
195                 .owner  = THIS_MODULE,
196         },
197         .remove         = __exit_p(ep93xx_rtc_remove),
198 };
199
200 static int __init ep93xx_rtc_init(void)
201 {
202         return platform_driver_probe(&ep93xx_rtc_driver, ep93xx_rtc_probe);
203 }
204
205 static void __exit ep93xx_rtc_exit(void)
206 {
207         platform_driver_unregister(&ep93xx_rtc_driver);
208 }
209
210 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
211 MODULE_DESCRIPTION("EP93XX RTC driver");
212 MODULE_LICENSE("GPL");
213 MODULE_VERSION(DRV_VERSION);
214
215 module_init(ep93xx_rtc_init);
216 module_exit(ep93xx_rtc_exit);