media: tegra: add supporting for RAW8/RAW10 input and output
[linux-2.6.git] / drivers / rtc / rtc-ds1216.c
1 /*
2  * Dallas DS1216 RTC driver
3  *
4  * Copyright (c) 2007 Thomas Bogendoerfer
5  *
6  */
7
8 #include <linux/module.h>
9 #include <linux/rtc.h>
10 #include <linux/platform_device.h>
11 #include <linux/bcd.h>
12 #include <linux/slab.h>
13
14 #define DRV_VERSION "0.2"
15
16 struct ds1216_regs {
17         u8 tsec;
18         u8 sec;
19         u8 min;
20         u8 hour;
21         u8 wday;
22         u8 mday;
23         u8 month;
24         u8 year;
25 };
26
27 #define DS1216_HOUR_1224        (1 << 7)
28 #define DS1216_HOUR_AMPM        (1 << 5)
29
30 struct ds1216_priv {
31         struct rtc_device *rtc;
32         void __iomem *ioaddr;
33         size_t size;
34         unsigned long baseaddr;
35 };
36
37 static const u8 magic[] = {
38         0xc5, 0x3a, 0xa3, 0x5c, 0xc5, 0x3a, 0xa3, 0x5c
39 };
40
41 /*
42  * Read the 64 bit we'd like to have - It a series
43  * of 64 bits showing up in the LSB of the base register.
44  *
45  */
46 static void ds1216_read(u8 __iomem *ioaddr, u8 *buf)
47 {
48         unsigned char c;
49         int i, j;
50
51         for (i = 0; i < 8; i++) {
52                 c = 0;
53                 for (j = 0; j < 8; j++)
54                         c |= (readb(ioaddr) & 0x1) << j;
55                 buf[i] = c;
56         }
57 }
58
59 static void ds1216_write(u8 __iomem *ioaddr, const u8 *buf)
60 {
61         unsigned char c;
62         int i, j;
63
64         for (i = 0; i < 8; i++) {
65                 c = buf[i];
66                 for (j = 0; j < 8; j++) {
67                         writeb(c, ioaddr);
68                         c = c >> 1;
69                 }
70         }
71 }
72
73 static void ds1216_switch_ds_to_clock(u8 __iomem *ioaddr)
74 {
75         /* Reset magic pointer */
76         readb(ioaddr);
77         /* Write 64 bit magic to DS1216 */
78         ds1216_write(ioaddr, magic);
79 }
80
81 static int ds1216_rtc_read_time(struct device *dev, struct rtc_time *tm)
82 {
83         struct platform_device *pdev = to_platform_device(dev);
84         struct ds1216_priv *priv = platform_get_drvdata(pdev);
85         struct ds1216_regs regs;
86
87         ds1216_switch_ds_to_clock(priv->ioaddr);
88         ds1216_read(priv->ioaddr, (u8 *)&regs);
89
90         tm->tm_sec = bcd2bin(regs.sec);
91         tm->tm_min = bcd2bin(regs.min);
92         if (regs.hour & DS1216_HOUR_1224) {
93                 /* AM/PM mode */
94                 tm->tm_hour = bcd2bin(regs.hour & 0x1f);
95                 if (regs.hour & DS1216_HOUR_AMPM)
96                         tm->tm_hour += 12;
97         } else
98                 tm->tm_hour = bcd2bin(regs.hour & 0x3f);
99         tm->tm_wday = (regs.wday & 7) - 1;
100         tm->tm_mday = bcd2bin(regs.mday & 0x3f);
101         tm->tm_mon = bcd2bin(regs.month & 0x1f);
102         tm->tm_year = bcd2bin(regs.year);
103         if (tm->tm_year < 70)
104                 tm->tm_year += 100;
105
106         return rtc_valid_tm(tm);
107 }
108
109 static int ds1216_rtc_set_time(struct device *dev, struct rtc_time *tm)
110 {
111         struct platform_device *pdev = to_platform_device(dev);
112         struct ds1216_priv *priv = platform_get_drvdata(pdev);
113         struct ds1216_regs regs;
114
115         ds1216_switch_ds_to_clock(priv->ioaddr);
116         ds1216_read(priv->ioaddr, (u8 *)&regs);
117
118         regs.tsec = 0; /* clear 0.1 and 0.01 seconds */
119         regs.sec = bin2bcd(tm->tm_sec);
120         regs.min = bin2bcd(tm->tm_min);
121         regs.hour &= DS1216_HOUR_1224;
122         if (regs.hour && tm->tm_hour > 12) {
123                 regs.hour |= DS1216_HOUR_AMPM;
124                 tm->tm_hour -= 12;
125         }
126         regs.hour |= bin2bcd(tm->tm_hour);
127         regs.wday &= ~7;
128         regs.wday |= tm->tm_wday;
129         regs.mday = bin2bcd(tm->tm_mday);
130         regs.month = bin2bcd(tm->tm_mon);
131         regs.year = bin2bcd(tm->tm_year % 100);
132
133         ds1216_switch_ds_to_clock(priv->ioaddr);
134         ds1216_write(priv->ioaddr, (u8 *)&regs);
135         return 0;
136 }
137
138 static const struct rtc_class_ops ds1216_rtc_ops = {
139         .read_time      = ds1216_rtc_read_time,
140         .set_time       = ds1216_rtc_set_time,
141 };
142
143 static int __init ds1216_rtc_probe(struct platform_device *pdev)
144 {
145         struct resource *res;
146         struct ds1216_priv *priv;
147         int ret = 0;
148         u8 dummy[8];
149
150         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
151         if (!res)
152                 return -ENODEV;
153         priv = kzalloc(sizeof *priv, GFP_KERNEL);
154         if (!priv)
155                 return -ENOMEM;
156
157         platform_set_drvdata(pdev, priv);
158
159         priv->size = resource_size(res);
160         if (!request_mem_region(res->start, priv->size, pdev->name)) {
161                 ret = -EBUSY;
162                 goto out;
163         }
164         priv->baseaddr = res->start;
165         priv->ioaddr = ioremap(priv->baseaddr, priv->size);
166         if (!priv->ioaddr) {
167                 ret = -ENOMEM;
168                 goto out;
169         }
170         priv->rtc = rtc_device_register("ds1216", &pdev->dev,
171                                   &ds1216_rtc_ops, THIS_MODULE);
172         if (IS_ERR(priv->rtc)) {
173                 ret = PTR_ERR(priv->rtc);
174                 goto out;
175         }
176
177         /* dummy read to get clock into a known state */
178         ds1216_read(priv->ioaddr, dummy);
179         return 0;
180
181 out:
182         if (priv->ioaddr)
183                 iounmap(priv->ioaddr);
184         if (priv->baseaddr)
185                 release_mem_region(priv->baseaddr, priv->size);
186         kfree(priv);
187         return ret;
188 }
189
190 static int __exit ds1216_rtc_remove(struct platform_device *pdev)
191 {
192         struct ds1216_priv *priv = platform_get_drvdata(pdev);
193
194         rtc_device_unregister(priv->rtc);
195         iounmap(priv->ioaddr);
196         release_mem_region(priv->baseaddr, priv->size);
197         kfree(priv);
198         return 0;
199 }
200
201 static struct platform_driver ds1216_rtc_platform_driver = {
202         .driver         = {
203                 .name   = "rtc-ds1216",
204                 .owner  = THIS_MODULE,
205         },
206         .remove         = __exit_p(ds1216_rtc_remove),
207 };
208
209 static int __init ds1216_rtc_init(void)
210 {
211         return platform_driver_probe(&ds1216_rtc_platform_driver, ds1216_rtc_probe);
212 }
213
214 static void __exit ds1216_rtc_exit(void)
215 {
216         platform_driver_unregister(&ds1216_rtc_platform_driver);
217 }
218
219 MODULE_AUTHOR("Thomas Bogendoerfer <tsbogend@alpha.franken.de>");
220 MODULE_DESCRIPTION("DS1216 RTC driver");
221 MODULE_LICENSE("GPL");
222 MODULE_VERSION(DRV_VERSION);
223 MODULE_ALIAS("platform:rtc-ds1216");
224
225 module_init(ds1216_rtc_init);
226 module_exit(ds1216_rtc_exit);