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Diffstat (limited to 'arch/cris/arch-v32/drivers/pcf8563.c')
-rw-r--r--arch/cris/arch-v32/drivers/pcf8563.c341
1 files changed, 341 insertions, 0 deletions
diff --git a/arch/cris/arch-v32/drivers/pcf8563.c b/arch/cris/arch-v32/drivers/pcf8563.c
new file mode 100644
index 000000000000..f894580b648b
--- /dev/null
+++ b/arch/cris/arch-v32/drivers/pcf8563.c
@@ -0,0 +1,341 @@
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/config.h>
21#include <linux/version.h>
22#include <linux/module.h>
23#include <linux/kernel.h>
24#include <linux/types.h>
25#include <linux/sched.h>
26#include <linux/init.h>
27#include <linux/fs.h>
28#include <linux/ioctl.h>
29#include <linux/delay.h>
30#include <linux/bcd.h>
31
32#include <asm/uaccess.h>
33#include <asm/system.h>
34#include <asm/io.h>
35#include <asm/rtc.h>
36
37#include "i2c.h"
38
39#define PCF8563_MAJOR 121 /* Local major number. */
40#define DEVICE_NAME "rtc" /* Name which is registered in /proc/devices. */
41#define PCF8563_NAME "PCF8563"
42#define DRIVER_VERSION "$Revision: 1.1 $"
43
44/* Two simple wrapper macros, saves a few keystrokes. */
45#define rtc_read(x) i2c_readreg(RTC_I2C_READ, x)
46#define rtc_write(x,y) i2c_writereg(RTC_I2C_WRITE, x, y)
47
48static const unsigned char days_in_month[] =
49 { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
50
51int pcf8563_ioctl(struct inode *, struct file *, unsigned int, unsigned long);
52int pcf8563_open(struct inode *, struct file *);
53int pcf8563_release(struct inode *, struct file *);
54
55static struct file_operations pcf8563_fops = {
56 owner: THIS_MODULE,
57 ioctl: pcf8563_ioctl,
58 open: pcf8563_open,
59 release: pcf8563_release,
60};
61
62unsigned char
63pcf8563_readreg(int reg)
64{
65 unsigned char res = rtc_read(reg);
66
67 /* The PCF8563 does not return 0 for unimplemented bits */
68 switch (reg) {
69 case RTC_SECONDS:
70 case RTC_MINUTES:
71 res &= 0x7F;
72 break;
73 case RTC_HOURS:
74 case RTC_DAY_OF_MONTH:
75 res &= 0x3F;
76 break;
77 case RTC_WEEKDAY:
78 res &= 0x07;
79 break;
80 case RTC_MONTH:
81 res &= 0x1F;
82 break;
83 case RTC_CONTROL1:
84 res &= 0xA8;
85 break;
86 case RTC_CONTROL2:
87 res &= 0x1F;
88 break;
89 case RTC_CLOCKOUT_FREQ:
90 case RTC_TIMER_CONTROL:
91 res &= 0x83;
92 break;
93 }
94 return res;
95}
96
97void
98pcf8563_writereg(int reg, unsigned char val)
99{
100#ifdef CONFIG_ETRAX_RTC_READONLY
101 if (reg == RTC_CONTROL1 || (reg >= RTC_SECONDS && reg <= RTC_YEAR))
102 return;
103#endif
104
105 rtc_write(reg, val);
106}
107
108void
109get_rtc_time(struct rtc_time *tm)
110{
111 tm->tm_sec = rtc_read(RTC_SECONDS);
112 tm->tm_min = rtc_read(RTC_MINUTES);
113 tm->tm_hour = rtc_read(RTC_HOURS);
114 tm->tm_mday = rtc_read(RTC_DAY_OF_MONTH);
115 tm->tm_wday = rtc_read(RTC_WEEKDAY);
116 tm->tm_mon = rtc_read(RTC_MONTH);
117 tm->tm_year = rtc_read(RTC_YEAR);
118
119 if (tm->tm_sec & 0x80)
120 printk(KERN_WARNING "%s: RTC Voltage Low - reliable date/time "
121 "information is no longer guaranteed!\n", PCF8563_NAME);
122
123 tm->tm_year = BCD_TO_BIN(tm->tm_year) + ((tm->tm_mon & 0x80) ? 100 : 0);
124 tm->tm_sec &= 0x7F;
125 tm->tm_min &= 0x7F;
126 tm->tm_hour &= 0x3F;
127 tm->tm_mday &= 0x3F;
128 tm->tm_wday &= 0x07; /* Not coded in BCD. */
129 tm->tm_mon &= 0x1F;
130
131 BCD_TO_BIN(tm->tm_sec);
132 BCD_TO_BIN(tm->tm_min);
133 BCD_TO_BIN(tm->tm_hour);
134 BCD_TO_BIN(tm->tm_mday);
135 BCD_TO_BIN(tm->tm_mon);
136 tm->tm_mon--; /* Month is 1..12 in RTC but 0..11 in linux */
137}
138
139int __init
140pcf8563_init(void)
141{
142 /* Initiate the i2c protocol. */
143 i2c_init();
144
145 /*
146 * First of all we need to reset the chip. This is done by
147 * clearing control1, control2 and clk freq and resetting
148 * all alarms.
149 */
150 if (rtc_write(RTC_CONTROL1, 0x00) < 0)
151 goto err;
152
153 if (rtc_write(RTC_CONTROL2, 0x00) < 0)
154 goto err;
155
156 if (rtc_write(RTC_CLOCKOUT_FREQ, 0x00) < 0)
157 goto err;
158
159 if (rtc_write(RTC_TIMER_CONTROL, 0x03) < 0)
160 goto err;
161
162 /* Reset the alarms. */
163 if (rtc_write(RTC_MINUTE_ALARM, 0x80) < 0)
164 goto err;
165
166 if (rtc_write(RTC_HOUR_ALARM, 0x80) < 0)
167 goto err;
168
169 if (rtc_write(RTC_DAY_ALARM, 0x80) < 0)
170 goto err;
171
172 if (rtc_write(RTC_WEEKDAY_ALARM, 0x80) < 0)
173 goto err;
174
175 if (register_chrdev(PCF8563_MAJOR, DEVICE_NAME, &pcf8563_fops) < 0) {
176 printk(KERN_INFO "%s: Unable to get major numer %d for RTC device.\n",
177 PCF8563_NAME, PCF8563_MAJOR);
178 return -1;
179 }
180
181 printk(KERN_INFO "%s Real-Time Clock Driver, %s\n", PCF8563_NAME, DRIVER_VERSION);
182
183 /* Check for low voltage, and warn about it.. */
184 if (rtc_read(RTC_SECONDS) & 0x80)
185 printk(KERN_WARNING "%s: RTC Voltage Low - reliable date/time "
186 "information is no longer guaranteed!\n", PCF8563_NAME);
187
188 return 0;
189
190err:
191 printk(KERN_INFO "%s: Error initializing chip.\n", PCF8563_NAME);
192 return -1;
193}
194
195void __exit
196pcf8563_exit(void)
197{
198 if (unregister_chrdev(PCF8563_MAJOR, DEVICE_NAME) < 0) {
199 printk(KERN_INFO "%s: Unable to unregister device.\n", PCF8563_NAME);
200 }
201}
202
203/*
204 * ioctl calls for this driver. Why return -ENOTTY upon error? Because
205 * POSIX says so!
206 */
207int
208pcf8563_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
209{
210 /* Some sanity checks. */
211 if (_IOC_TYPE(cmd) != RTC_MAGIC)
212 return -ENOTTY;
213
214 if (_IOC_NR(cmd) > RTC_MAX_IOCTL)
215 return -ENOTTY;
216
217 switch (cmd) {
218 case RTC_RD_TIME:
219 {
220 struct rtc_time tm;
221
222 memset(&tm, 0, sizeof (struct rtc_time));
223 get_rtc_time(&tm);
224
225 if (copy_to_user((struct rtc_time *) arg, &tm, sizeof tm)) {
226 return -EFAULT;
227 }
228
229 return 0;
230 }
231
232 case RTC_SET_TIME:
233 {
234#ifdef CONFIG_ETRAX_RTC_READONLY
235 return -EPERM;
236#else
237 int leap;
238 int year;
239 int century;
240 struct rtc_time tm;
241
242 if (!capable(CAP_SYS_TIME))
243 return -EPERM;
244
245 if (copy_from_user(&tm, (struct rtc_time *) arg, sizeof tm))
246 return -EFAULT;
247
248 /* Convert from struct tm to struct rtc_time. */
249 tm.tm_year += 1900;
250 tm.tm_mon += 1;
251
252 /*
253 * Check if tm.tm_year is a leap year. A year is a leap
254 * year if it is divisible by 4 but not 100, except
255 * that years divisible by 400 _are_ leap years.
256 */
257 year = tm.tm_year;
258 leap = (tm.tm_mon == 2) && ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0);
259
260 /* Perform some sanity checks. */
261 if ((tm.tm_year < 1970) ||
262 (tm.tm_mon > 12) ||
263 (tm.tm_mday == 0) ||
264 (tm.tm_mday > days_in_month[tm.tm_mon] + leap) ||
265 (tm.tm_wday >= 7) ||
266 (tm.tm_hour >= 24) ||
267 (tm.tm_min >= 60) ||
268 (tm.tm_sec >= 60))
269 return -EINVAL;
270
271 century = (tm.tm_year >= 2000) ? 0x80 : 0;
272 tm.tm_year = tm.tm_year % 100;
273
274 BIN_TO_BCD(tm.tm_year);
275 BIN_TO_BCD(tm.tm_mday);
276 BIN_TO_BCD(tm.tm_hour);
277 BIN_TO_BCD(tm.tm_min);
278 BIN_TO_BCD(tm.tm_sec);
279 tm.tm_mon |= century;
280
281 rtc_write(RTC_YEAR, tm.tm_year);
282 rtc_write(RTC_MONTH, tm.tm_mon);
283 rtc_write(RTC_WEEKDAY, tm.tm_wday); /* Not coded in BCD. */
284 rtc_write(RTC_DAY_OF_MONTH, tm.tm_mday);
285 rtc_write(RTC_HOURS, tm.tm_hour);
286 rtc_write(RTC_MINUTES, tm.tm_min);
287 rtc_write(RTC_SECONDS, tm.tm_sec);
288
289 return 0;
290#endif /* !CONFIG_ETRAX_RTC_READONLY */
291 }
292
293 case RTC_VLOW_RD:
294 {
295 int vl_bit = 0;
296
297 if (rtc_read(RTC_SECONDS) & 0x80) {
298 vl_bit = 1;
299 printk(KERN_WARNING "%s: RTC Voltage Low - reliable "
300 "date/time information is no longer guaranteed!\n",
301 PCF8563_NAME);
302 }
303 if (copy_to_user((int *) arg, &vl_bit, sizeof(int)))
304 return -EFAULT;
305
306 return 0;
307 }
308
309 case RTC_VLOW_SET:
310 {
311 /* Clear the VL bit in the seconds register */
312 int ret = rtc_read(RTC_SECONDS);
313
314 rtc_write(RTC_SECONDS, (ret & 0x7F));
315
316 return 0;
317 }
318
319 default:
320 return -ENOTTY;
321 }
322
323 return 0;
324}
325
326int
327pcf8563_open(struct inode *inode, struct file *filp)
328{
329 MOD_INC_USE_COUNT;
330 return 0;
331}
332
333int
334pcf8563_release(struct inode *inode, struct file *filp)
335{
336 MOD_DEC_USE_COUNT;
337 return 0;
338}
339
340module_init(pcf8563_init);
341module_exit(pcf8563_exit);