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Linux 3.3-rc6
[linux/fpc-iii.git] / drivers / rtc / rtc-at91rm9200.c
blobdc474bc6522de1d44295f67ad3ddb1f7bc33a771
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
31 #include <asm/uaccess.h>
32
33 #include <mach/at91_rtc.h>
34
35 #define at91_rtc_read(field) \
36 __raw_readl(at91_rtc_regs + field)
37 #define at91_rtc_write(field, val) \
38 __raw_writel((val), at91_rtc_regs + field)
39
40 #define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */
41
42 static DECLARE_COMPLETION(at91_rtc_updated);
43 static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
44 static void __iomem *at91_rtc_regs;
45 static int irq;
46
47 /*
48 * Decode time/date into rtc_time structure
49 */
50 static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg,
51 struct rtc_time *tm)
52 {
53 unsigned int time, date;
54
55 /* must read twice in case it changes */
56 do {
57 time = at91_rtc_read(timereg);
58 date = at91_rtc_read(calreg);
59 } while ((time != at91_rtc_read(timereg)) ||
60 (date != at91_rtc_read(calreg)));
61
62 tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0);
63 tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8);
64 tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16);
65
66 /*
67 * The Calendar Alarm register does not have a field for
68 * the year - so these will return an invalid value. When an
69 * alarm is set, at91_alarm_year will store the current year.
70 */
71 tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */
72 tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */
73
74 tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */
75 tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1;
76 tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24);
77 }
78
79 /*
80 * Read current time and date in RTC
81 */
82 static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm)
83 {
84 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm);
85 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
86 tm->tm_year = tm->tm_year - 1900;
87
88 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
89 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
90 tm->tm_hour, tm->tm_min, tm->tm_sec);
91
92 return 0;
93 }
94
95 /*
96 * Set current time and date in RTC
97 */
98 static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
99 {
100 unsigned long cr;
101
102 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
103 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
104 tm->tm_hour, tm->tm_min, tm->tm_sec);
105
106 /* Stop Time/Calendar from counting */
107 cr = at91_rtc_read(AT91_RTC_CR);
108 at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
109
110 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ACKUPD);
111 wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
112 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD);
113
114 at91_rtc_write(AT91_RTC_TIMR,
115 bin2bcd(tm->tm_sec) << 0
116 | bin2bcd(tm->tm_min) << 8
117 | bin2bcd(tm->tm_hour) << 16);
118
119 at91_rtc_write(AT91_RTC_CALR,
120 bin2bcd((tm->tm_year + 1900) / 100) /* century */
121 | bin2bcd(tm->tm_year % 100) << 8 /* year */
122 | bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
123 | bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
124 | bin2bcd(tm->tm_mday) << 24);
125
126 /* Restart Time/Calendar */
127 cr = at91_rtc_read(AT91_RTC_CR);
128 at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM));
129
130 return 0;
131 }
132
133 /*
134 * Read alarm time and date in RTC
135 */
136 static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
137 {
138 struct rtc_time *tm = &alrm->time;
139
140 at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
141 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
142 tm->tm_year = at91_alarm_year - 1900;
143
144 alrm->enabled = (at91_rtc_read(AT91_RTC_IMR) & AT91_RTC_ALARM)
145 ? 1 : 0;
146
147 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
148 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
149 tm->tm_hour, tm->tm_min, tm->tm_sec);
150
151 return 0;
152 }
153
154 /*
155 * Set alarm time and date in RTC
156 */
157 static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
158 {
159 struct rtc_time tm;
160
161 at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm);
162
163 at91_alarm_year = tm.tm_year;
164
165 tm.tm_hour = alrm->time.tm_hour;
166 tm.tm_min = alrm->time.tm_min;
167 tm.tm_sec = alrm->time.tm_sec;
168
169 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM);
170 at91_rtc_write(AT91_RTC_TIMALR,
171 bin2bcd(tm.tm_sec) << 0
172 | bin2bcd(tm.tm_min) << 8
173 | bin2bcd(tm.tm_hour) << 16
174 | AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN);
175 at91_rtc_write(AT91_RTC_CALALR,
176 bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */
177 | bin2bcd(tm.tm_mday) << 24
178 | AT91_RTC_DATEEN | AT91_RTC_MTHEN);
179
180 if (alrm->enabled) {
181 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
182 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM);
183 }
184
185 pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
186 at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
187 tm.tm_min, tm.tm_sec);
188
189 return 0;
190 }
191
192 static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
193 {
194 pr_debug("%s(): cmd=%08x\n", __func__, enabled);
195
196 if (enabled) {
197 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
198 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM);
199 } else
200 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM);
201
202 return 0;
203 }
204 /*
205 * Provide additional RTC information in /proc/driver/rtc
206 */
207 static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
208 {
209 unsigned long imr = at91_rtc_read(AT91_RTC_IMR);
210
211 seq_printf(seq, "update_IRQ\t: %s\n",
212 (imr & AT91_RTC_ACKUPD) ? "yes" : "no");
213 seq_printf(seq, "periodic_IRQ\t: %s\n",
214 (imr & AT91_RTC_SECEV) ? "yes" : "no");
215
216 return 0;
217 }
218
219 /*
220 * IRQ handler for the RTC
221 */
222 static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
223 {
224 struct platform_device *pdev = dev_id;
225 struct rtc_device *rtc = platform_get_drvdata(pdev);
226 unsigned int rtsr;
227 unsigned long events = 0;
228
229 rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read(AT91_RTC_IMR);
230 if (rtsr) { /* this interrupt is shared! Is it ours? */
231 if (rtsr & AT91_RTC_ALARM)
232 events |= (RTC_AF | RTC_IRQF);
233 if (rtsr & AT91_RTC_SECEV)
234 events |= (RTC_UF | RTC_IRQF);
235 if (rtsr & AT91_RTC_ACKUPD)
236 complete(&at91_rtc_updated);
237
238 at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
239
240 rtc_update_irq(rtc, 1, events);
241
242 pr_debug("%s(): num=%ld, events=0x%02lx\n", __func__,
243 events >> 8, events & 0x000000FF);
244
245 return IRQ_HANDLED;
246 }
247 return IRQ_NONE; /* not handled */
248 }
249
250 static const struct rtc_class_ops at91_rtc_ops = {
251 .read_time = at91_rtc_readtime,
252 .set_time = at91_rtc_settime,
253 .read_alarm = at91_rtc_readalarm,
254 .set_alarm = at91_rtc_setalarm,
255 .proc = at91_rtc_proc,
256 .alarm_irq_enable = at91_rtc_alarm_irq_enable,
257 };
258
259 /*
260 * Initialize and install RTC driver
261 */
262 static int __init at91_rtc_probe(struct platform_device *pdev)
263 {
264 struct rtc_device *rtc;
265 struct resource *regs;
266 int ret = 0;
267
268 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
269 if (!regs) {
270 dev_err(&pdev->dev, "no mmio resource defined\n");
271 return -ENXIO;
272 }
273
274 irq = platform_get_irq(pdev, 0);
275 if (irq < 0) {
276 dev_err(&pdev->dev, "no irq resource defined\n");
277 return -ENXIO;
278 }
279
280 at91_rtc_regs = ioremap(regs->start, resource_size(regs));
281 if (!at91_rtc_regs) {
282 dev_err(&pdev->dev, "failed to map registers, aborting.\n");
283 return -ENOMEM;
284 }
285
286 at91_rtc_write(AT91_RTC_CR, 0);
287 at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */
288
289 /* Disable all interrupts */
290 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
291 AT91_RTC_SECEV | AT91_RTC_TIMEV |
292 AT91_RTC_CALEV);
293
294 ret = request_irq(irq, at91_rtc_interrupt,
295 IRQF_SHARED,
296 "at91_rtc", pdev);
297 if (ret) {
298 printk(KERN_ERR "at91_rtc: IRQ %d already in use.\n",
299 irq);
300 return ret;
301 }
302
303 /* cpu init code should really have flagged this device as
304 * being wake-capable; if it didn't, do that here.
305 */
306 if (!device_can_wakeup(&pdev->dev))
307 device_init_wakeup(&pdev->dev, 1);
308
309 rtc = rtc_device_register(pdev->name, &pdev->dev,
310 &at91_rtc_ops, THIS_MODULE);
311 if (IS_ERR(rtc)) {
312 free_irq(irq, pdev);
313 return PTR_ERR(rtc);
314 }
315 platform_set_drvdata(pdev, rtc);
316
317 printk(KERN_INFO "AT91 Real Time Clock driver.\n");
318 return 0;
319 }
320
321 /*
322 * Disable and remove the RTC driver
323 */
324 static int __exit at91_rtc_remove(struct platform_device *pdev)
325 {
326 struct rtc_device *rtc = platform_get_drvdata(pdev);
327
328 /* Disable all interrupts */
329 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
330 AT91_RTC_SECEV | AT91_RTC_TIMEV |
331 AT91_RTC_CALEV);
332 free_irq(irq, pdev);
333
334 rtc_device_unregister(rtc);
335 platform_set_drvdata(pdev, NULL);
336
337 return 0;
338 }
339
340 #ifdef CONFIG_PM
341
342 /* AT91RM9200 RTC Power management control */
343
344 static u32 at91_rtc_imr;
345
346 static int at91_rtc_suspend(struct device *dev)
347 {
348 /* this IRQ is shared with DBGU and other hardware which isn't
349 * necessarily doing PM like we are...
350 */
351 at91_rtc_imr = at91_rtc_read(AT91_RTC_IMR)
352 & (AT91_RTC_ALARM|AT91_RTC_SECEV);
353 if (at91_rtc_imr) {
354 if (device_may_wakeup(dev))
355 enable_irq_wake(irq);
356 else
357 at91_rtc_write(AT91_RTC_IDR, at91_rtc_imr);
358 }
359 return 0;
360 }
361
362 static int at91_rtc_resume(struct device *dev)
363 {
364 if (at91_rtc_imr) {
365 if (device_may_wakeup(dev))
366 disable_irq_wake(irq);
367 else
368 at91_rtc_write(AT91_RTC_IER, at91_rtc_imr);
369 }
370 return 0;
371 }
372
373 static const struct dev_pm_ops at91_rtc_pm = {
374 .suspend = at91_rtc_suspend,
375 .resume = at91_rtc_resume,
376 };
377
378 #define at91_rtc_pm_ptr &at91_rtc_pm
379
380 #else
381 #define at91_rtc_pm_ptr NULL
382 #endif
383
384 static struct platform_driver at91_rtc_driver = {
385 .remove = __exit_p(at91_rtc_remove),
386 .driver = {
387 .name = "at91_rtc",
388 .owner = THIS_MODULE,
389 .pm = at91_rtc_pm_ptr,
390 },
391 };
392
393 static int __init at91_rtc_init(void)
394 {
395 return platform_driver_probe(&at91_rtc_driver, at91_rtc_probe);
396 }
397
398 static void __exit at91_rtc_exit(void)
399 {
400 platform_driver_unregister(&at91_rtc_driver);
401 }
402
403 module_init(at91_rtc_init);
404 module_exit(at91_rtc_exit);
405
406 MODULE_AUTHOR("Rick Bronson");
407 MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200");
408 MODULE_LICENSE("GPL");
409 MODULE_ALIAS("platform:at91_rtc");
Linux with added FPC-III support