?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
arm: at91: move at91rm9200 rtc header in drivers/rtc
[linux-2.6.git] / drivers / rtc / rtc-at91rm9200.c
blobb6469e2cae897b0a8fbc503ae88e9e2c53a74fee
1 /*
2 * Real Time Clock interface for Linux on Atmel AT91RM9200
3 *
4 * Copyright (C) 2002 Rick Bronson
5 *
6 * Converted to RTC class model by Andrew Victor
7 *
8 * Ported to Linux 2.6 by Steven Scholz
9 * Based on s3c2410-rtc.c Simtec Electronics
10 *
11 * Based on sa1100-rtc.c by Nils Faerber
12 * Based on rtc.c by Paul Gortmaker
13 *
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License
16 * as published by the Free Software Foundation; either version
17 * 2 of the License, or (at your option) any later version.
18 *
19 */
20
21 #include <linux/module.h>
22 #include <linux/kernel.h>
23 #include <linux/platform_device.h>
24 #include <linux/time.h>
25 #include <linux/rtc.h>
26 #include <linux/bcd.h>
27 #include <linux/interrupt.h>
28 #include <linux/ioctl.h>
29 #include <linux/completion.h>
30 #include <linux/io.h>
31
32 #include <asm/uaccess.h>
33
34 #include "rtc-at91rm9200.h"
35
36 #define at91_rtc_read(field) \
37 __raw_readl(at91_rtc_regs + field)
38 #define at91_rtc_write(field, val) \
39 __raw_writel((val), at91_rtc_regs + field)
40
41 #define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */
42
43 static DECLARE_COMPLETION(at91_rtc_updated);
44 static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
45 static void __iomem *at91_rtc_regs;
46 static int irq;
47
48 /*
49 * Decode time/date into rtc_time structure
50 */
51 static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg,
52 struct rtc_time *tm)
53 {
54 unsigned int time, date;
55
56 /* must read twice in case it changes */
57 do {
58 time = at91_rtc_read(timereg);
59 date = at91_rtc_read(calreg);
60 } while ((time != at91_rtc_read(timereg)) ||
61 (date != at91_rtc_read(calreg)));
62
63 tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0);
64 tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8);
65 tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16);
66
67 /*
68 * The Calendar Alarm register does not have a field for
69 * the year - so these will return an invalid value. When an
70 * alarm is set, at91_alarm_year will store the current year.
71 */
72 tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */
73 tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */
74
75 tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */
76 tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1;
77 tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24);
78 }
79
80 /*
81 * Read current time and date in RTC
82 */
83 static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm)
84 {
85 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm);
86 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
87 tm->tm_year = tm->tm_year - 1900;
88
89 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
90 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
91 tm->tm_hour, tm->tm_min, tm->tm_sec);
92
93 return 0;
94 }
95
96 /*
97 * Set current time and date in RTC
98 */
99 static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
100 {
101 unsigned long cr;
102
103 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
104 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
105 tm->tm_hour, tm->tm_min, tm->tm_sec);
106
107 /* Stop Time/Calendar from counting */
108 cr = at91_rtc_read(AT91_RTC_CR);
109 at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
110
111 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ACKUPD);
112 wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
113 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD);
114
115 at91_rtc_write(AT91_RTC_TIMR,
116 bin2bcd(tm->tm_sec) << 0
117 | bin2bcd(tm->tm_min) << 8
118 | bin2bcd(tm->tm_hour) << 16);
119
120 at91_rtc_write(AT91_RTC_CALR,
121 bin2bcd((tm->tm_year + 1900) / 100) /* century */
122 | bin2bcd(tm->tm_year % 100) << 8 /* year */
123 | bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
124 | bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
125 | bin2bcd(tm->tm_mday) << 24);
126
127 /* Restart Time/Calendar */
128 cr = at91_rtc_read(AT91_RTC_CR);
129 at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM));
130
131 return 0;
132 }
133
134 /*
135 * Read alarm time and date in RTC
136 */
137 static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
138 {
139 struct rtc_time *tm = &alrm->time;
140
141 at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
142 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
143 tm->tm_year = at91_alarm_year - 1900;
144
145 alrm->enabled = (at91_rtc_read(AT91_RTC_IMR) & AT91_RTC_ALARM)
146 ? 1 : 0;
147
148 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
149 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
150 tm->tm_hour, tm->tm_min, tm->tm_sec);
151
152 return 0;
153 }
154
155 /*
156 * Set alarm time and date in RTC
157 */
158 static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
159 {
160 struct rtc_time tm;
161
162 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);
163
164 at91_alarm_year = tm.tm_year;
165
166 tm.tm_hour = alrm->time.tm_hour;
167 tm.tm_min = alrm->time.tm_min;
168 tm.tm_sec = alrm->time.tm_sec;
169
170 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM);
171 at91_rtc_write(AT91_RTC_TIMALR,
172 bin2bcd(tm.tm_sec) << 0
173 | bin2bcd(tm.tm_min) << 8
174 | bin2bcd(tm.tm_hour) << 16
175 | AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN);
176 at91_rtc_write(AT91_RTC_CALALR,
177 bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */
178 | bin2bcd(tm.tm_mday) << 24
179 | AT91_RTC_DATEEN | AT91_RTC_MTHEN);
180
181 if (alrm->enabled) {
182 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
183 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM);
184 }
185
186 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
187 at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
188 tm.tm_min, tm.tm_sec);
189
190 return 0;
191 }
192
193 static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
194 {
195 pr_debug("%s(): cmd=%08x\n", __func__, enabled);
196
197 if (enabled) {
198 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
199 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM);
200 } else
201 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM);
202
203 return 0;
204 }
205 /*
206 * Provide additional RTC information in /proc/driver/rtc
207 */
208 static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
209 {
210 unsigned long imr = at91_rtc_read(AT91_RTC_IMR);
211
212 seq_printf(seq, "update_IRQ\t: %s\n",
213 (imr & AT91_RTC_ACKUPD) ? "yes" : "no");
214 seq_printf(seq, "periodic_IRQ\t: %s\n",
215 (imr & AT91_RTC_SECEV) ? "yes" : "no");
216
217 return 0;
218 }
219
220 /*
221 * IRQ handler for the RTC
222 */
223 static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
224 {
225 struct platform_device *pdev = dev_id;
226 struct rtc_device *rtc = platform_get_drvdata(pdev);
227 unsigned int rtsr;
228 unsigned long events = 0;
229
230 rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read(AT91_RTC_IMR);
231 if (rtsr) { /* this interrupt is shared! Is it ours? */
232 if (rtsr & AT91_RTC_ALARM)
233 events |= (RTC_AF | RTC_IRQF);
234 if (rtsr & AT91_RTC_SECEV)
235 events |= (RTC_UF | RTC_IRQF);
236 if (rtsr & AT91_RTC_ACKUPD)
237 complete(&at91_rtc_updated);
238
239 at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
240
241 rtc_update_irq(rtc, 1, events);
242
243 pr_debug("%s(): num=%ld, events=0x%02lx\n", __func__,
244 events >> 8, events & 0x000000FF);
245
246 return IRQ_HANDLED;
247 }
248 return IRQ_NONE; /* not handled */
249 }
250
251 static const struct rtc_class_ops at91_rtc_ops = {
252 .read_time = at91_rtc_readtime,
253 .set_time = at91_rtc_settime,
254 .read_alarm = at91_rtc_readalarm,
255 .set_alarm = at91_rtc_setalarm,
256 .proc = at91_rtc_proc,
257 .alarm_irq_enable = at91_rtc_alarm_irq_enable,
258 };
259
260 /*
261 * Initialize and install RTC driver
262 */
263 static int __init at91_rtc_probe(struct platform_device *pdev)
264 {
265 struct rtc_device *rtc;
266 struct resource *regs;
267 int ret = 0;
268
269 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
270 if (!regs) {
271 dev_err(&pdev->dev, "no mmio resource defined\n");
272 return -ENXIO;
273 }
274
275 irq = platform_get_irq(pdev, 0);
276 if (irq < 0) {
277 dev_err(&pdev->dev, "no irq resource defined\n");
278 return -ENXIO;
279 }
280
281 at91_rtc_regs = ioremap(regs->start, resource_size(regs));
282 if (!at91_rtc_regs) {
283 dev_err(&pdev->dev, "failed to map registers, aborting.\n");
284 return -ENOMEM;
285 }
286
287 at91_rtc_write(AT91_RTC_CR, 0);
288 at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */
289
290 /* Disable all interrupts */
291 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
292 AT91_RTC_SECEV | AT91_RTC_TIMEV |
293 AT91_RTC_CALEV);
294
295 ret = request_irq(irq, at91_rtc_interrupt,
296 IRQF_SHARED,
297 "at91_rtc", pdev);
298 if (ret) {
299 printk(KERN_ERR "at91_rtc: IRQ %d already in use.\n",
300 irq);
301 return ret;
302 }
303
304 /* cpu init code should really have flagged this device as
305 * being wake-capable; if it didn't, do that here.
306 */
307 if (!device_can_wakeup(&pdev->dev))
308 device_init_wakeup(&pdev->dev, 1);
309
310 rtc = rtc_device_register(pdev->name, &pdev->dev,
311 &at91_rtc_ops, THIS_MODULE);
312 if (IS_ERR(rtc)) {
313 free_irq(irq, pdev);
314 return PTR_ERR(rtc);
315 }
316 platform_set_drvdata(pdev, rtc);
317
318 printk(KERN_INFO "AT91 Real Time Clock driver.\n");
319 return 0;
320 }
321
322 /*
323 * Disable and remove the RTC driver
324 */
325 static int __exit at91_rtc_remove(struct platform_device *pdev)
326 {
327 struct rtc_device *rtc = platform_get_drvdata(pdev);
328
329 /* Disable all interrupts */
330 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
331 AT91_RTC_SECEV | AT91_RTC_TIMEV |
332 AT91_RTC_CALEV);
333 free_irq(irq, pdev);
334
335 rtc_device_unregister(rtc);
336 platform_set_drvdata(pdev, NULL);
337
338 return 0;
339 }
340
341 #ifdef CONFIG_PM
342
343 /* AT91RM9200 RTC Power management control */
344
345 static u32 at91_rtc_imr;
346
347 static int at91_rtc_suspend(struct device *dev)
348 {
349 /* this IRQ is shared with DBGU and other hardware which isn't
350 * necessarily doing PM like we are...
351 */
352 at91_rtc_imr = at91_rtc_read(AT91_RTC_IMR)
353 & (AT91_RTC_ALARM|AT91_RTC_SECEV);
354 if (at91_rtc_imr) {
355 if (device_may_wakeup(dev))
356 enable_irq_wake(irq);
357 else
358 at91_rtc_write(AT91_RTC_IDR, at91_rtc_imr);
359 }
360 return 0;
361 }
362
363 static int at91_rtc_resume(struct device *dev)
364 {
365 if (at91_rtc_imr) {
366 if (device_may_wakeup(dev))
367 disable_irq_wake(irq);
368 else
369 at91_rtc_write(AT91_RTC_IER, at91_rtc_imr);
370 }
371 return 0;
372 }
373
374 static const struct dev_pm_ops at91_rtc_pm = {
375 .suspend = at91_rtc_suspend,
376 .resume = at91_rtc_resume,
377 };
378
379 #define at91_rtc_pm_ptr &at91_rtc_pm
380
381 #else
382 #define at91_rtc_pm_ptr NULL
383 #endif
384
385 static struct platform_driver at91_rtc_driver = {
386 .remove = __exit_p(at91_rtc_remove),
387 .driver = {
388 .name = "at91_rtc",
389 .owner = THIS_MODULE,
390 .pm = at91_rtc_pm_ptr,
391 },
392 };
393
394 static int __init at91_rtc_init(void)
395 {
396 return platform_driver_probe(&at91_rtc_driver, at91_rtc_probe);
397 }
398
399 static void __exit at91_rtc_exit(void)
400 {
401 platform_driver_unregister(&at91_rtc_driver);
402 }
403
404 module_init(at91_rtc_init);
405 module_exit(at91_rtc_exit);
406
407 MODULE_AUTHOR("Rick Bronson");
408 MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");
409 MODULE_LICENSE("GPL");
410 MODULE_ALIAS("platform:at91_rtc");
Linus' kernel tree