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Linux 2.6.20.7
[linux/fpc-iii.git] / drivers / rtc / rtc-s3c.c
blobf406a2b55aea829b48e05b53180e40e8b1a48a04
1 /* drivers/rtc/rtc-s3c.c
2 *
3 * Copyright (c) 2004,2006 Simtec Electronics
4 * Ben Dooks, <ben@simtec.co.uk>
5 * http://armlinux.simtec.co.uk/
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * S3C2410/S3C2440/S3C24XX Internal RTC Driver
12 */
13
14 #include <linux/module.h>
15 #include <linux/fs.h>
16 #include <linux/string.h>
17 #include <linux/init.h>
18 #include <linux/platform_device.h>
19 #include <linux/interrupt.h>
20 #include <linux/rtc.h>
21 #include <linux/bcd.h>
22 #include <linux/clk.h>
23
24 #include <asm/hardware.h>
25 #include <asm/uaccess.h>
26 #include <asm/io.h>
27 #include <asm/irq.h>
28 #include <asm/rtc.h>
29
30 #include <asm/mach/time.h>
31
32 #include <asm/arch/regs-rtc.h>
33
34 /* I have yet to find an S3C implementation with more than one
35 * of these rtc blocks in */
36
37 static struct resource *s3c_rtc_mem;
38
39 static void __iomem *s3c_rtc_base;
40 static int s3c_rtc_alarmno = NO_IRQ;
41 static int s3c_rtc_tickno = NO_IRQ;
42 static int s3c_rtc_freq = 1;
43
44 static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
45 static unsigned int tick_count;
46
47 /* IRQ Handlers */
48
49 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
50 {
51 struct rtc_device *rdev = id;
52
53 rtc_update_irq(&rdev->class_dev, 1, RTC_AF | RTC_IRQF);
54 return IRQ_HANDLED;
55 }
56
57 static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
58 {
59 struct rtc_device *rdev = id;
60
61 rtc_update_irq(&rdev->class_dev, tick_count++, RTC_PF | RTC_IRQF);
62 return IRQ_HANDLED;
63 }
64
65 /* Update control registers */
66 static void s3c_rtc_setaie(int to)
67 {
68 unsigned int tmp;
69
70 pr_debug("%s: aie=%d\n", __FUNCTION__, to);
71
72 tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
73
74 if (to)
75 tmp |= S3C2410_RTCALM_ALMEN;
76
77 writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
78 }
79
80 static void s3c_rtc_setpie(int to)
81 {
82 unsigned int tmp;
83
84 pr_debug("%s: pie=%d\n", __FUNCTION__, to);
85
86 spin_lock_irq(&s3c_rtc_pie_lock);
87 tmp = readb(s3c_rtc_base + S3C2410_TICNT) & ~S3C2410_TICNT_ENABLE;
88
89 if (to)
90 tmp |= S3C2410_TICNT_ENABLE;
91
92 writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
93 spin_unlock_irq(&s3c_rtc_pie_lock);
94 }
95
96 static void s3c_rtc_setfreq(int freq)
97 {
98 unsigned int tmp;
99
100 spin_lock_irq(&s3c_rtc_pie_lock);
101 tmp = readb(s3c_rtc_base + S3C2410_TICNT) & S3C2410_TICNT_ENABLE;
102
103 s3c_rtc_freq = freq;
104
105 tmp |= (128 / freq)-1;
106
107 writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
108 spin_unlock_irq(&s3c_rtc_pie_lock);
109 }
110
111 /* Time read/write */
112
113 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
114 {
115 unsigned int have_retried = 0;
116 void __iomem *base = s3c_rtc_base;
117
118 retry_get_time:
119 rtc_tm->tm_min = readb(base + S3C2410_RTCMIN);
120 rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
121 rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE);
122 rtc_tm->tm_mon = readb(base + S3C2410_RTCMON);
123 rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR);
124 rtc_tm->tm_sec = readb(base + S3C2410_RTCSEC);
125
126 /* the only way to work out wether the system was mid-update
127 * when we read it is to check the second counter, and if it
128 * is zero, then we re-try the entire read
129 */
130
131 if (rtc_tm->tm_sec == 0 && !have_retried) {
132 have_retried = 1;
133 goto retry_get_time;
134 }
135
136 pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
137 rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
138 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
139
140 BCD_TO_BIN(rtc_tm->tm_sec);
141 BCD_TO_BIN(rtc_tm->tm_min);
142 BCD_TO_BIN(rtc_tm->tm_hour);
143 BCD_TO_BIN(rtc_tm->tm_mday);
144 BCD_TO_BIN(rtc_tm->tm_mon);
145 BCD_TO_BIN(rtc_tm->tm_year);
146
147 rtc_tm->tm_year += 100;
148 rtc_tm->tm_mon -= 1;
149
150 return 0;
151 }
152
153 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
154 {
155 void __iomem *base = s3c_rtc_base;
156 int year = tm->tm_year - 100;
157
158 pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n",
159 tm->tm_year, tm->tm_mon, tm->tm_mday,
160 tm->tm_hour, tm->tm_min, tm->tm_sec);
161
162 /* we get around y2k by simply not supporting it */
163
164 if (year < 0 || year >= 100) {
165 dev_err(dev, "rtc only supports 100 years\n");
166 return -EINVAL;
167 }
168
169 writeb(BIN2BCD(tm->tm_sec), base + S3C2410_RTCSEC);
170 writeb(BIN2BCD(tm->tm_min), base + S3C2410_RTCMIN);
171 writeb(BIN2BCD(tm->tm_hour), base + S3C2410_RTCHOUR);
172 writeb(BIN2BCD(tm->tm_mday), base + S3C2410_RTCDATE);
173 writeb(BIN2BCD(tm->tm_mon + 1), base + S3C2410_RTCMON);
174 writeb(BIN2BCD(year), base + S3C2410_RTCYEAR);
175
176 return 0;
177 }
178
179 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
180 {
181 struct rtc_time *alm_tm = &alrm->time;
182 void __iomem *base = s3c_rtc_base;
183 unsigned int alm_en;
184
185 alm_tm->tm_sec = readb(base + S3C2410_ALMSEC);
186 alm_tm->tm_min = readb(base + S3C2410_ALMMIN);
187 alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
188 alm_tm->tm_mon = readb(base + S3C2410_ALMMON);
189 alm_tm->tm_mday = readb(base + S3C2410_ALMDATE);
190 alm_tm->tm_year = readb(base + S3C2410_ALMYEAR);
191
192 alm_en = readb(base + S3C2410_RTCALM);
193
194 alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
195
196 pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
197 alm_en,
198 alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
199 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
200
201
202 /* decode the alarm enable field */
203
204 if (alm_en & S3C2410_RTCALM_SECEN)
205 BCD_TO_BIN(alm_tm->tm_sec);
206 else
207 alm_tm->tm_sec = 0xff;
208
209 if (alm_en & S3C2410_RTCALM_MINEN)
210 BCD_TO_BIN(alm_tm->tm_min);
211 else
212 alm_tm->tm_min = 0xff;
213
214 if (alm_en & S3C2410_RTCALM_HOUREN)
215 BCD_TO_BIN(alm_tm->tm_hour);
216 else
217 alm_tm->tm_hour = 0xff;
218
219 if (alm_en & S3C2410_RTCALM_DAYEN)
220 BCD_TO_BIN(alm_tm->tm_mday);
221 else
222 alm_tm->tm_mday = 0xff;
223
224 if (alm_en & S3C2410_RTCALM_MONEN) {
225 BCD_TO_BIN(alm_tm->tm_mon);
226 alm_tm->tm_mon -= 1;
227 } else {
228 alm_tm->tm_mon = 0xff;
229 }
230
231 if (alm_en & S3C2410_RTCALM_YEAREN)
232 BCD_TO_BIN(alm_tm->tm_year);
233 else
234 alm_tm->tm_year = 0xffff;
235
236 return 0;
237 }
238
239 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
240 {
241 struct rtc_time *tm = &alrm->time;
242 void __iomem *base = s3c_rtc_base;
243 unsigned int alrm_en;
244
245 pr_debug("s3c_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
246 alrm->enabled,
247 tm->tm_mday & 0xff, tm->tm_mon & 0xff, tm->tm_year & 0xff,
248 tm->tm_hour & 0xff, tm->tm_min & 0xff, tm->tm_sec);
249
250
251 alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
252 writeb(0x00, base + S3C2410_RTCALM);
253
254 if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
255 alrm_en |= S3C2410_RTCALM_SECEN;
256 writeb(BIN2BCD(tm->tm_sec), base + S3C2410_ALMSEC);
257 }
258
259 if (tm->tm_min < 60 && tm->tm_min >= 0) {
260 alrm_en |= S3C2410_RTCALM_MINEN;
261 writeb(BIN2BCD(tm->tm_min), base + S3C2410_ALMMIN);
262 }
263
264 if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
265 alrm_en |= S3C2410_RTCALM_HOUREN;
266 writeb(BIN2BCD(tm->tm_hour), base + S3C2410_ALMHOUR);
267 }
268
269 pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);
270
271 writeb(alrm_en, base + S3C2410_RTCALM);
272
273 if (0) {
274 alrm_en = readb(base + S3C2410_RTCALM);
275 alrm_en &= ~S3C2410_RTCALM_ALMEN;
276 writeb(alrm_en, base + S3C2410_RTCALM);
277 disable_irq_wake(s3c_rtc_alarmno);
278 }
279
280 if (alrm->enabled)
281 enable_irq_wake(s3c_rtc_alarmno);
282 else
283 disable_irq_wake(s3c_rtc_alarmno);
284
285 return 0;
286 }
287
288 static int s3c_rtc_ioctl(struct device *dev,
289 unsigned int cmd, unsigned long arg)
290 {
291 unsigned int ret = -ENOIOCTLCMD;
292
293 switch (cmd) {
294 case RTC_AIE_OFF:
295 case RTC_AIE_ON:
296 s3c_rtc_setaie((cmd == RTC_AIE_ON) ? 1 : 0);
297 ret = 0;
298 break;
299
300 case RTC_PIE_OFF:
301 case RTC_PIE_ON:
302 tick_count = 0;
303 s3c_rtc_setpie((cmd == RTC_PIE_ON) ? 1 : 0);
304 ret = 0;
305 break;
306
307 case RTC_IRQP_READ:
308 ret = put_user(s3c_rtc_freq, (unsigned long __user *)arg);
309 break;
310
311 case RTC_IRQP_SET:
312 /* check for power of 2 */
313
314 if ((arg & (arg-1)) != 0 || arg < 1) {
315 ret = -EINVAL;
316 goto exit;
317 }
318
319 pr_debug("s3c2410_rtc: setting frequency %ld\n", arg);
320
321 s3c_rtc_setfreq(arg);
322 ret = 0;
323 break;
324
325 case RTC_UIE_ON:
326 case RTC_UIE_OFF:
327 ret = -EINVAL;
328 }
329
330 exit:
331 return ret;
332 }
333
334 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
335 {
336 unsigned int ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
337
338 seq_printf(seq, "periodic_IRQ\t: %s\n",
339 (ticnt & S3C2410_TICNT_ENABLE) ? "yes" : "no" );
340
341 seq_printf(seq, "periodic_freq\t: %d\n", s3c_rtc_freq);
342
343 return 0;
344 }
345
346 static int s3c_rtc_open(struct device *dev)
347 {
348 struct platform_device *pdev = to_platform_device(dev);
349 struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
350 int ret;
351
352 ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
353 SA_INTERRUPT, "s3c2410-rtc alarm", rtc_dev);
354
355 if (ret) {
356 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
357 return ret;
358 }
359
360 ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
361 SA_INTERRUPT, "s3c2410-rtc tick", rtc_dev);
362
363 if (ret) {
364 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
365 goto tick_err;
366 }
367
368 return ret;
369
370 tick_err:
371 free_irq(s3c_rtc_alarmno, rtc_dev);
372 return ret;
373 }
374
375 static void s3c_rtc_release(struct device *dev)
376 {
377 struct platform_device *pdev = to_platform_device(dev);
378 struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
379
380 /* do not clear AIE here, it may be needed for wake */
381
382 s3c_rtc_setpie(0);
383 free_irq(s3c_rtc_alarmno, rtc_dev);
384 free_irq(s3c_rtc_tickno, rtc_dev);
385 }
386
387 static const struct rtc_class_ops s3c_rtcops = {
388 .open = s3c_rtc_open,
389 .release = s3c_rtc_release,
390 .ioctl = s3c_rtc_ioctl,
391 .read_time = s3c_rtc_gettime,
392 .set_time = s3c_rtc_settime,
393 .read_alarm = s3c_rtc_getalarm,
394 .set_alarm = s3c_rtc_setalarm,
395 .proc = s3c_rtc_proc,
396 };
397
398 static void s3c_rtc_enable(struct platform_device *pdev, int en)
399 {
400 void __iomem *base = s3c_rtc_base;
401 unsigned int tmp;
402
403 if (s3c_rtc_base == NULL)
404 return;
405
406 if (!en) {
407 tmp = readb(base + S3C2410_RTCCON);
408 writeb(tmp & ~S3C2410_RTCCON_RTCEN, base + S3C2410_RTCCON);
409
410 tmp = readb(base + S3C2410_TICNT);
411 writeb(tmp & ~S3C2410_TICNT_ENABLE, base + S3C2410_TICNT);
412 } else {
413 /* re-enable the device, and check it is ok */
414
415 if ((readb(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0){
416 dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
417
418 tmp = readb(base + S3C2410_RTCCON);
419 writeb(tmp|S3C2410_RTCCON_RTCEN, base+S3C2410_RTCCON);
420 }
421
422 if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)){
423 dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
424
425 tmp = readb(base + S3C2410_RTCCON);
426 writeb(tmp& ~S3C2410_RTCCON_CNTSEL, base+S3C2410_RTCCON);
427 }
428
429 if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)){
430 dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
431
432 tmp = readb(base + S3C2410_RTCCON);
433 writeb(tmp & ~S3C2410_RTCCON_CLKRST, base+S3C2410_RTCCON);
434 }
435 }
436 }
437
438 static int s3c_rtc_remove(struct platform_device *dev)
439 {
440 struct rtc_device *rtc = platform_get_drvdata(dev);
441
442 platform_set_drvdata(dev, NULL);
443 rtc_device_unregister(rtc);
444
445 s3c_rtc_setpie(0);
446 s3c_rtc_setaie(0);
447
448 iounmap(s3c_rtc_base);
449 release_resource(s3c_rtc_mem);
450 kfree(s3c_rtc_mem);
451
452 return 0;
453 }
454
455 static int s3c_rtc_probe(struct platform_device *pdev)
456 {
457 struct rtc_device *rtc;
458 struct resource *res;
459 int ret;
460
461 pr_debug("%s: probe=%p\n", __FUNCTION__, pdev);
462
463 /* find the IRQs */
464
465 s3c_rtc_tickno = platform_get_irq(pdev, 1);
466 if (s3c_rtc_tickno < 0) {
467 dev_err(&pdev->dev, "no irq for rtc tick\n");
468 return -ENOENT;
469 }
470
471 s3c_rtc_alarmno = platform_get_irq(pdev, 0);
472 if (s3c_rtc_alarmno < 0) {
473 dev_err(&pdev->dev, "no irq for alarm\n");
474 return -ENOENT;
475 }
476
477 pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
478 s3c_rtc_tickno, s3c_rtc_alarmno);
479
480 /* get the memory region */
481
482 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
483 if (res == NULL) {
484 dev_err(&pdev->dev, "failed to get memory region resource\n");
485 return -ENOENT;
486 }
487
488 s3c_rtc_mem = request_mem_region(res->start,
489 res->end-res->start+1,
490 pdev->name);
491
492 if (s3c_rtc_mem == NULL) {
493 dev_err(&pdev->dev, "failed to reserve memory region\n");
494 ret = -ENOENT;
495 goto err_nores;
496 }
497
498 s3c_rtc_base = ioremap(res->start, res->end - res->start + 1);
499 if (s3c_rtc_base == NULL) {
500 dev_err(&pdev->dev, "failed ioremap()\n");
501 ret = -EINVAL;
502 goto err_nomap;
503 }
504
505 /* check to see if everything is setup correctly */
506
507 s3c_rtc_enable(pdev, 1);
508
509 pr_debug("s3c2410_rtc: RTCCON=%02x\n",
510 readb(s3c_rtc_base + S3C2410_RTCCON));
511
512 s3c_rtc_setfreq(s3c_rtc_freq);
513
514 /* register RTC and exit */
515
516 rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
517 THIS_MODULE);
518
519 if (IS_ERR(rtc)) {
520 dev_err(&pdev->dev, "cannot attach rtc\n");
521 ret = PTR_ERR(rtc);
522 goto err_nortc;
523 }
524
525 rtc->max_user_freq = 128;
526
527 platform_set_drvdata(pdev, rtc);
528 return 0;
529
530 err_nortc:
531 s3c_rtc_enable(pdev, 0);
532 iounmap(s3c_rtc_base);
533
534 err_nomap:
535 release_resource(s3c_rtc_mem);
536
537 err_nores:
538 return ret;
539 }
540
541 #ifdef CONFIG_PM
542
543 /* RTC Power management control */
544
545 static struct timespec s3c_rtc_delta;
546
547 static int ticnt_save;
548
549 static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
550 {
551 struct rtc_time tm;
552 struct timespec time;
553
554 time.tv_nsec = 0;
555
556 /* save TICNT for anyone using periodic interrupts */
557
558 ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
559
560 /* calculate time delta for suspend */
561
562 s3c_rtc_gettime(&pdev->dev, &tm);
563 rtc_tm_to_time(&tm, &time.tv_sec);
564 save_time_delta(&s3c_rtc_delta, &time);
565 s3c_rtc_enable(pdev, 0);
566
567 return 0;
568 }
569
570 static int s3c_rtc_resume(struct platform_device *pdev)
571 {
572 struct rtc_time tm;
573 struct timespec time;
574
575 time.tv_nsec = 0;
576
577 s3c_rtc_enable(pdev, 1);
578 s3c_rtc_gettime(&pdev->dev, &tm);
579 rtc_tm_to_time(&tm, &time.tv_sec);
580 restore_time_delta(&s3c_rtc_delta, &time);
581
582 writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
583 return 0;
584 }
585 #else
586 #define s3c_rtc_suspend NULL
587 #define s3c_rtc_resume NULL
588 #endif
589
590 static struct platform_driver s3c2410_rtcdrv = {
591 .probe = s3c_rtc_probe,
592 .remove = s3c_rtc_remove,
593 .suspend = s3c_rtc_suspend,
594 .resume = s3c_rtc_resume,
595 .driver = {
596 .name = "s3c2410-rtc",
597 .owner = THIS_MODULE,
598 },
599 };
600
601 static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
602
603 static int __init s3c_rtc_init(void)
604 {
605 printk(banner);
606 return platform_driver_register(&s3c2410_rtcdrv);
607 }
608
609 static void __exit s3c_rtc_exit(void)
610 {
611 platform_driver_unregister(&s3c2410_rtcdrv);
612 }
613
614 module_init(s3c_rtc_init);
615 module_exit(s3c_rtc_exit);
616
617 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
618 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
619 MODULE_LICENSE("GPL");
Linux with added FPC-III support