Remove obsolete #include <linux/config.h>
[linux-2.6.git] / arch / cris / arch-v32 / drivers / pcf8563.c
1 /*
2  * PCF8563 RTC
3  *
4  * From Phillips' datasheet:
5  *
6  * The PCF8563 is a CMOS real-time clock/calendar optimized for low power
7  * consumption. A programmable clock output, interupt output and voltage
8  * low detector are also provided. All address and data are transferred
9  * serially via two-line bidirectional I2C-bus. Maximum bus speed is
10  * 400 kbits/s. The built-in word address register is incremented
11  * automatically after each written or read byte.
12  *
13  * Copyright (c) 2002-2003, Axis Communications AB
14  * All rights reserved.
15  *
16  * Author: Tobias Anderberg <tobiasa@axis.com>.
17  *
18  */
19
20 #include <linux/module.h>
21 #include <linux/kernel.h>
22 #include <linux/types.h>
23 #include <linux/sched.h>
24 #include <linux/init.h>
25 #include <linux/fs.h>
26 #include <linux/ioctl.h>
27 #include <linux/delay.h>
28 #include <linux/bcd.h>
29
30 #include <asm/uaccess.h>
31 #include <asm/system.h>
32 #include <asm/io.h>
33 #include <asm/rtc.h>
34
35 #include "i2c.h"
36
37 #define PCF8563_MAJOR   121     /* Local major number. */
38 #define DEVICE_NAME     "rtc"   /* Name which is registered in /proc/devices. */
39 #define PCF8563_NAME    "PCF8563"
40 #define DRIVER_VERSION  "$Revision: 1.1 $"
41
42 /* Two simple wrapper macros, saves a few keystrokes. */
43 #define rtc_read(x) i2c_readreg(RTC_I2C_READ, x)
44 #define rtc_write(x,y) i2c_writereg(RTC_I2C_WRITE, x, y)
45
46 static const unsigned char days_in_month[] =
47         { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
48
49 int pcf8563_ioctl(struct inode *, struct file *, unsigned int, unsigned long);
50 int pcf8563_open(struct inode *, struct file *);
51 int pcf8563_release(struct inode *, struct file *);
52
53 static struct file_operations pcf8563_fops = {
54         owner: THIS_MODULE,
55         ioctl: pcf8563_ioctl,
56         open: pcf8563_open,
57         release: pcf8563_release,
58 };
59
60 unsigned char
61 pcf8563_readreg(int reg)
62 {
63         unsigned char res = rtc_read(reg);
64
65         /* The PCF8563 does not return 0 for unimplemented bits */
66         switch (reg) {
67                 case RTC_SECONDS:
68                 case RTC_MINUTES:
69                         res &= 0x7F;
70                         break;
71                 case RTC_HOURS:
72                 case RTC_DAY_OF_MONTH:
73                         res &= 0x3F;
74                         break;
75                 case RTC_WEEKDAY:
76                         res &= 0x07;
77                         break;
78                 case RTC_MONTH:
79                         res &= 0x1F;
80                         break;
81                 case RTC_CONTROL1:
82                         res &= 0xA8;
83                         break;
84                 case RTC_CONTROL2:
85                         res &= 0x1F;
86                         break;
87                 case RTC_CLOCKOUT_FREQ:
88                 case RTC_TIMER_CONTROL:
89                         res &= 0x83;
90                         break;
91         }
92         return res;
93 }
94
95 void
96 pcf8563_writereg(int reg, unsigned char val)
97 {
98 #ifdef CONFIG_ETRAX_RTC_READONLY
99         if (reg == RTC_CONTROL1 || (reg >= RTC_SECONDS && reg <= RTC_YEAR))
100                 return;
101 #endif
102
103         rtc_write(reg, val);
104 }
105
106 void
107 get_rtc_time(struct rtc_time *tm)
108 {
109         tm->tm_sec  = rtc_read(RTC_SECONDS);
110         tm->tm_min  = rtc_read(RTC_MINUTES);
111         tm->tm_hour = rtc_read(RTC_HOURS);
112         tm->tm_mday = rtc_read(RTC_DAY_OF_MONTH);
113         tm->tm_wday = rtc_read(RTC_WEEKDAY);
114         tm->tm_mon  = rtc_read(RTC_MONTH);
115         tm->tm_year = rtc_read(RTC_YEAR);
116
117         if (tm->tm_sec & 0x80)
118                 printk(KERN_WARNING "%s: RTC Voltage Low - reliable date/time "
119                        "information is no longer guaranteed!\n", PCF8563_NAME);
120
121         tm->tm_year  = BCD_TO_BIN(tm->tm_year) + ((tm->tm_mon & 0x80) ? 100 : 0);
122         tm->tm_sec  &= 0x7F;
123         tm->tm_min  &= 0x7F;
124         tm->tm_hour &= 0x3F;
125         tm->tm_mday &= 0x3F;
126         tm->tm_wday &= 0x07; /* Not coded in BCD. */
127         tm->tm_mon  &= 0x1F;
128
129         BCD_TO_BIN(tm->tm_sec);
130         BCD_TO_BIN(tm->tm_min);
131         BCD_TO_BIN(tm->tm_hour);
132         BCD_TO_BIN(tm->tm_mday);
133         BCD_TO_BIN(tm->tm_mon);
134         tm->tm_mon--; /* Month is 1..12 in RTC but 0..11 in linux */
135 }
136
137 int __init
138 pcf8563_init(void)
139 {
140         /* Initiate the i2c protocol. */
141         i2c_init();
142
143         /*
144          * First of all we need to reset the chip. This is done by
145          * clearing control1, control2 and clk freq and resetting
146          * all alarms.
147          */
148         if (rtc_write(RTC_CONTROL1, 0x00) < 0)
149                 goto err;
150
151         if (rtc_write(RTC_CONTROL2, 0x00) < 0)
152                 goto err;
153
154         if (rtc_write(RTC_CLOCKOUT_FREQ, 0x00) < 0)
155                 goto err;
156
157         if (rtc_write(RTC_TIMER_CONTROL, 0x03) < 0)
158                 goto err;
159
160         /* Reset the alarms. */
161         if (rtc_write(RTC_MINUTE_ALARM, 0x80) < 0)
162                 goto err;
163
164         if (rtc_write(RTC_HOUR_ALARM, 0x80) < 0)
165                 goto err;
166
167         if (rtc_write(RTC_DAY_ALARM, 0x80) < 0)
168                 goto err;
169
170         if (rtc_write(RTC_WEEKDAY_ALARM, 0x80) < 0)
171                 goto err;
172
173         if (register_chrdev(PCF8563_MAJOR, DEVICE_NAME, &pcf8563_fops) < 0) {
174                 printk(KERN_INFO "%s: Unable to get major numer %d for RTC device.\n",
175                        PCF8563_NAME, PCF8563_MAJOR);
176                 return -1;
177         }
178
179         printk(KERN_INFO "%s Real-Time Clock Driver, %s\n", PCF8563_NAME, DRIVER_VERSION);
180
181         /* Check for low voltage, and warn about it.. */
182         if (rtc_read(RTC_SECONDS) & 0x80)
183                 printk(KERN_WARNING "%s: RTC Voltage Low - reliable date/time "
184                        "information is no longer guaranteed!\n", PCF8563_NAME);
185
186         return 0;
187
188 err:
189         printk(KERN_INFO "%s: Error initializing chip.\n", PCF8563_NAME);
190         return -1;
191 }
192
193 void __exit
194 pcf8563_exit(void)
195 {
196         if (unregister_chrdev(PCF8563_MAJOR, DEVICE_NAME) < 0) {
197                 printk(KERN_INFO "%s: Unable to unregister device.\n", PCF8563_NAME);
198         }
199 }
200
201 /*
202  * ioctl calls for this driver. Why return -ENOTTY upon error? Because
203  * POSIX says so!
204  */
205 int
206 pcf8563_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
207 {
208         /* Some sanity checks. */
209         if (_IOC_TYPE(cmd) != RTC_MAGIC)
210                 return -ENOTTY;
211
212         if (_IOC_NR(cmd) > RTC_MAX_IOCTL)
213                 return -ENOTTY;
214
215         switch (cmd) {
216                 case RTC_RD_TIME:
217                 {
218                         struct rtc_time tm;
219
220                         memset(&tm, 0, sizeof (struct rtc_time));
221                         get_rtc_time(&tm);
222
223                         if (copy_to_user((struct rtc_time *) arg, &tm, sizeof tm)) {
224                                 return -EFAULT;
225                         }
226
227                         return 0;
228                 }
229
230                 case RTC_SET_TIME:
231                 {
232 #ifdef CONFIG_ETRAX_RTC_READONLY
233                         return -EPERM;
234 #else
235                         int leap;
236                         int year;
237                         int century;
238                         struct rtc_time tm;
239
240                         if (!capable(CAP_SYS_TIME))
241                                 return -EPERM;
242
243                         if (copy_from_user(&tm, (struct rtc_time *) arg, sizeof tm))
244                                 return -EFAULT;
245
246                         /* Convert from struct tm to struct rtc_time. */
247                         tm.tm_year += 1900;
248                         tm.tm_mon += 1;
249
250                         /*
251                          * Check if tm.tm_year is a leap year. A year is a leap
252                          * year if it is divisible by 4 but not 100, except
253                          * that years divisible by 400 _are_ leap years.
254                          */
255                         year = tm.tm_year;
256                         leap = (tm.tm_mon == 2) && ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0);
257
258                         /* Perform some sanity checks. */
259                         if ((tm.tm_year < 1970) ||
260                             (tm.tm_mon > 12) ||
261                             (tm.tm_mday == 0) ||
262                             (tm.tm_mday > days_in_month[tm.tm_mon] + leap) ||
263                             (tm.tm_wday >= 7) ||
264                             (tm.tm_hour >= 24) ||
265                             (tm.tm_min >= 60) ||
266                             (tm.tm_sec >= 60))
267                                 return -EINVAL;
268
269                         century = (tm.tm_year >= 2000) ? 0x80 : 0;
270                         tm.tm_year = tm.tm_year % 100;
271
272                         BIN_TO_BCD(tm.tm_year);
273                         BIN_TO_BCD(tm.tm_mday);
274                         BIN_TO_BCD(tm.tm_hour);
275                         BIN_TO_BCD(tm.tm_min);
276                         BIN_TO_BCD(tm.tm_sec);
277                         tm.tm_mon |= century;
278
279                         rtc_write(RTC_YEAR, tm.tm_year);
280                         rtc_write(RTC_MONTH, tm.tm_mon);
281                         rtc_write(RTC_WEEKDAY, tm.tm_wday); /* Not coded in BCD. */
282                         rtc_write(RTC_DAY_OF_MONTH, tm.tm_mday);
283                         rtc_write(RTC_HOURS, tm.tm_hour);
284                         rtc_write(RTC_MINUTES, tm.tm_min);
285                         rtc_write(RTC_SECONDS, tm.tm_sec);
286
287                         return 0;
288 #endif /* !CONFIG_ETRAX_RTC_READONLY */
289                 }
290
291                 case RTC_VLOW_RD:
292                 {
293                         int vl_bit = 0;
294
295                         if (rtc_read(RTC_SECONDS) & 0x80) {
296                                 vl_bit = 1;
297                                 printk(KERN_WARNING "%s: RTC Voltage Low - reliable "
298                                        "date/time information is no longer guaranteed!\n",
299                                        PCF8563_NAME);
300                         }
301                         if (copy_to_user((int *) arg, &vl_bit, sizeof(int)))
302                                 return -EFAULT;
303
304                         return 0;
305                 }
306
307                 case RTC_VLOW_SET:
308                 {
309                         /* Clear the VL bit in the seconds register */
310                         int ret = rtc_read(RTC_SECONDS);
311
312                         rtc_write(RTC_SECONDS, (ret & 0x7F));
313
314                         return 0;
315                 }
316
317                 default:
318                         return -ENOTTY;
319         }
320
321         return 0;
322 }
323
324 int
325 pcf8563_open(struct inode *inode, struct file *filp)
326 {
327         MOD_INC_USE_COUNT;
328         return 0;
329 }
330
331 int
332 pcf8563_release(struct inode *inode, struct file *filp)
333 {
334         MOD_DEC_USE_COUNT;
335         return 0;
336 }
337
338 module_init(pcf8563_init);
339 module_exit(pcf8563_exit);