[PATCH] Scheduled removal of SA_xxx interrupt flags fixups
[linux-2.6.git] / drivers / rtc / rtc-s3c.c
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                           IRQF_DISABLED,  "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                           IRQF_DISABLED,  "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");