rtc-r9701.c: silence compiler warning
[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 #include <linux/log2.h>
24
25 #include <asm/hardware.h>
26 #include <asm/uaccess.h>
27 #include <asm/io.h>
28 #include <asm/irq.h>
29 #include <asm/rtc.h>
30
31 #include <asm/mach/time.h>
32
33 #include <asm/plat-s3c/regs-rtc.h>
34
35 /* I have yet to find an S3C implementation with more than one
36  * of these rtc blocks in */
37
38 static struct resource *s3c_rtc_mem;
39
40 static void __iomem *s3c_rtc_base;
41 static int s3c_rtc_alarmno = NO_IRQ;
42 static int s3c_rtc_tickno  = NO_IRQ;
43 static int s3c_rtc_freq    = 1;
44
45 static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
46 static unsigned int tick_count;
47
48 /* IRQ Handlers */
49
50 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
51 {
52         struct rtc_device *rdev = id;
53
54         rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF);
55         return IRQ_HANDLED;
56 }
57
58 static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
59 {
60         struct rtc_device *rdev = id;
61
62         rtc_update_irq(rdev, tick_count++, RTC_PF | RTC_IRQF);
63         return IRQ_HANDLED;
64 }
65
66 /* Update control registers */
67 static void s3c_rtc_setaie(int to)
68 {
69         unsigned int tmp;
70
71         pr_debug("%s: aie=%d\n", __FUNCTION__, to);
72
73         tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
74
75         if (to)
76                 tmp |= S3C2410_RTCALM_ALMEN;
77
78         writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
79 }
80
81 static void s3c_rtc_setpie(int to)
82 {
83         unsigned int tmp;
84
85         pr_debug("%s: pie=%d\n", __FUNCTION__, to);
86
87         spin_lock_irq(&s3c_rtc_pie_lock);
88         tmp = readb(s3c_rtc_base + S3C2410_TICNT) & ~S3C2410_TICNT_ENABLE;
89
90         if (to)
91                 tmp |= S3C2410_TICNT_ENABLE;
92
93         writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
94         spin_unlock_irq(&s3c_rtc_pie_lock);
95 }
96
97 static void s3c_rtc_setfreq(int freq)
98 {
99         unsigned int tmp;
100
101         spin_lock_irq(&s3c_rtc_pie_lock);
102         tmp = readb(s3c_rtc_base + S3C2410_TICNT) & S3C2410_TICNT_ENABLE;
103
104         s3c_rtc_freq = freq;
105
106         tmp |= (128 / freq)-1;
107
108         writeb(tmp, s3c_rtc_base + S3C2410_TICNT);
109         spin_unlock_irq(&s3c_rtc_pie_lock);
110 }
111
112 /* Time read/write */
113
114 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
115 {
116         unsigned int have_retried = 0;
117         void __iomem *base = s3c_rtc_base;
118
119  retry_get_time:
120         rtc_tm->tm_min  = readb(base + S3C2410_RTCMIN);
121         rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
122         rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE);
123         rtc_tm->tm_mon  = readb(base + S3C2410_RTCMON);
124         rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR);
125         rtc_tm->tm_sec  = readb(base + S3C2410_RTCSEC);
126
127         /* the only way to work out wether the system was mid-update
128          * when we read it is to check the second counter, and if it
129          * is zero, then we re-try the entire read
130          */
131
132         if (rtc_tm->tm_sec == 0 && !have_retried) {
133                 have_retried = 1;
134                 goto retry_get_time;
135         }
136
137         pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
138                  rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
139                  rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
140
141         BCD_TO_BIN(rtc_tm->tm_sec);
142         BCD_TO_BIN(rtc_tm->tm_min);
143         BCD_TO_BIN(rtc_tm->tm_hour);
144         BCD_TO_BIN(rtc_tm->tm_mday);
145         BCD_TO_BIN(rtc_tm->tm_mon);
146         BCD_TO_BIN(rtc_tm->tm_year);
147
148         rtc_tm->tm_year += 100;
149         rtc_tm->tm_mon -= 1;
150
151         return 0;
152 }
153
154 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
155 {
156         void __iomem *base = s3c_rtc_base;
157         int year = tm->tm_year - 100;
158
159         pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n",
160                  tm->tm_year, tm->tm_mon, tm->tm_mday,
161                  tm->tm_hour, tm->tm_min, tm->tm_sec);
162
163         /* we get around y2k by simply not supporting it */
164
165         if (year < 0 || year >= 100) {
166                 dev_err(dev, "rtc only supports 100 years\n");
167                 return -EINVAL;
168         }
169
170         writeb(BIN2BCD(tm->tm_sec),  base + S3C2410_RTCSEC);
171         writeb(BIN2BCD(tm->tm_min),  base + S3C2410_RTCMIN);
172         writeb(BIN2BCD(tm->tm_hour), base + S3C2410_RTCHOUR);
173         writeb(BIN2BCD(tm->tm_mday), base + S3C2410_RTCDATE);
174         writeb(BIN2BCD(tm->tm_mon + 1), base + S3C2410_RTCMON);
175         writeb(BIN2BCD(year), base + S3C2410_RTCYEAR);
176
177         return 0;
178 }
179
180 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
181 {
182         struct rtc_time *alm_tm = &alrm->time;
183         void __iomem *base = s3c_rtc_base;
184         unsigned int alm_en;
185
186         alm_tm->tm_sec  = readb(base + S3C2410_ALMSEC);
187         alm_tm->tm_min  = readb(base + S3C2410_ALMMIN);
188         alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
189         alm_tm->tm_mon  = readb(base + S3C2410_ALMMON);
190         alm_tm->tm_mday = readb(base + S3C2410_ALMDATE);
191         alm_tm->tm_year = readb(base + S3C2410_ALMYEAR);
192
193         alm_en = readb(base + S3C2410_RTCALM);
194
195         alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
196
197         pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
198                  alm_en,
199                  alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
200                  alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
201
202
203         /* decode the alarm enable field */
204
205         if (alm_en & S3C2410_RTCALM_SECEN)
206                 BCD_TO_BIN(alm_tm->tm_sec);
207         else
208                 alm_tm->tm_sec = 0xff;
209
210         if (alm_en & S3C2410_RTCALM_MINEN)
211                 BCD_TO_BIN(alm_tm->tm_min);
212         else
213                 alm_tm->tm_min = 0xff;
214
215         if (alm_en & S3C2410_RTCALM_HOUREN)
216                 BCD_TO_BIN(alm_tm->tm_hour);
217         else
218                 alm_tm->tm_hour = 0xff;
219
220         if (alm_en & S3C2410_RTCALM_DAYEN)
221                 BCD_TO_BIN(alm_tm->tm_mday);
222         else
223                 alm_tm->tm_mday = 0xff;
224
225         if (alm_en & S3C2410_RTCALM_MONEN) {
226                 BCD_TO_BIN(alm_tm->tm_mon);
227                 alm_tm->tm_mon -= 1;
228         } else {
229                 alm_tm->tm_mon = 0xff;
230         }
231
232         if (alm_en & S3C2410_RTCALM_YEAREN)
233                 BCD_TO_BIN(alm_tm->tm_year);
234         else
235                 alm_tm->tm_year = 0xffff;
236
237         return 0;
238 }
239
240 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
241 {
242         struct rtc_time *tm = &alrm->time;
243         void __iomem *base = s3c_rtc_base;
244         unsigned int alrm_en;
245
246         pr_debug("s3c_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
247                  alrm->enabled,
248                  tm->tm_mday & 0xff, tm->tm_mon & 0xff, tm->tm_year & 0xff,
249                  tm->tm_hour & 0xff, tm->tm_min & 0xff, tm->tm_sec);
250
251
252         alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
253         writeb(0x00, base + S3C2410_RTCALM);
254
255         if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
256                 alrm_en |= S3C2410_RTCALM_SECEN;
257                 writeb(BIN2BCD(tm->tm_sec), base + S3C2410_ALMSEC);
258         }
259
260         if (tm->tm_min < 60 && tm->tm_min >= 0) {
261                 alrm_en |= S3C2410_RTCALM_MINEN;
262                 writeb(BIN2BCD(tm->tm_min), base + S3C2410_ALMMIN);
263         }
264
265         if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
266                 alrm_en |= S3C2410_RTCALM_HOUREN;
267                 writeb(BIN2BCD(tm->tm_hour), base + S3C2410_ALMHOUR);
268         }
269
270         pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);
271
272         writeb(alrm_en, base + S3C2410_RTCALM);
273
274         if (0) {
275                 alrm_en = readb(base + S3C2410_RTCALM);
276                 alrm_en &= ~S3C2410_RTCALM_ALMEN;
277                 writeb(alrm_en, base + S3C2410_RTCALM);
278                 disable_irq_wake(s3c_rtc_alarmno);
279         }
280
281         if (alrm->enabled)
282                 enable_irq_wake(s3c_rtc_alarmno);
283         else
284                 disable_irq_wake(s3c_rtc_alarmno);
285
286         return 0;
287 }
288
289 static int s3c_rtc_ioctl(struct device *dev,
290                          unsigned int cmd, unsigned long arg)
291 {
292         unsigned int ret = -ENOIOCTLCMD;
293
294         switch (cmd) {
295         case RTC_AIE_OFF:
296         case RTC_AIE_ON:
297                 s3c_rtc_setaie((cmd == RTC_AIE_ON) ? 1 : 0);
298                 ret = 0;
299                 break;
300
301         case RTC_PIE_OFF:
302         case RTC_PIE_ON:
303                 tick_count = 0;
304                 s3c_rtc_setpie((cmd == RTC_PIE_ON) ? 1 : 0);
305                 ret = 0;
306                 break;
307
308         case RTC_IRQP_READ:
309                 ret = put_user(s3c_rtc_freq, (unsigned long __user *)arg);
310                 break;
311
312         case RTC_IRQP_SET:
313                 if (!is_power_of_2(arg)) {
314                         ret = -EINVAL;
315                         goto exit;
316                 }
317
318                 pr_debug("s3c2410_rtc: setting frequency %ld\n", arg);
319
320                 s3c_rtc_setfreq(arg);
321                 ret = 0;
322                 break;
323
324         case RTC_UIE_ON:
325         case RTC_UIE_OFF:
326                 ret = -EINVAL;
327         }
328
329  exit:
330         return ret;
331 }
332
333 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
334 {
335         unsigned int ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
336
337         seq_printf(seq, "periodic_IRQ\t: %s\n",
338                      (ticnt & S3C2410_TICNT_ENABLE) ? "yes" : "no" );
339
340         seq_printf(seq, "periodic_freq\t: %d\n", s3c_rtc_freq);
341
342         return 0;
343 }
344
345 static int s3c_rtc_open(struct device *dev)
346 {
347         struct platform_device *pdev = to_platform_device(dev);
348         struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
349         int ret;
350
351         ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
352                           IRQF_DISABLED,  "s3c2410-rtc alarm", rtc_dev);
353
354         if (ret) {
355                 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
356                 return ret;
357         }
358
359         ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
360                           IRQF_DISABLED,  "s3c2410-rtc tick", rtc_dev);
361
362         if (ret) {
363                 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
364                 goto tick_err;
365         }
366
367         return ret;
368
369  tick_err:
370         free_irq(s3c_rtc_alarmno, rtc_dev);
371         return ret;
372 }
373
374 static void s3c_rtc_release(struct device *dev)
375 {
376         struct platform_device *pdev = to_platform_device(dev);
377         struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
378
379         /* do not clear AIE here, it may be needed for wake */
380
381         s3c_rtc_setpie(0);
382         free_irq(s3c_rtc_alarmno, rtc_dev);
383         free_irq(s3c_rtc_tickno, rtc_dev);
384 }
385
386 static const struct rtc_class_ops s3c_rtcops = {
387         .open           = s3c_rtc_open,
388         .release        = s3c_rtc_release,
389         .ioctl          = s3c_rtc_ioctl,
390         .read_time      = s3c_rtc_gettime,
391         .set_time       = s3c_rtc_settime,
392         .read_alarm     = s3c_rtc_getalarm,
393         .set_alarm      = s3c_rtc_setalarm,
394         .proc           = s3c_rtc_proc,
395 };
396
397 static void s3c_rtc_enable(struct platform_device *pdev, int en)
398 {
399         void __iomem *base = s3c_rtc_base;
400         unsigned int tmp;
401
402         if (s3c_rtc_base == NULL)
403                 return;
404
405         if (!en) {
406                 tmp = readb(base + S3C2410_RTCCON);
407                 writeb(tmp & ~S3C2410_RTCCON_RTCEN, base + S3C2410_RTCCON);
408
409                 tmp = readb(base + S3C2410_TICNT);
410                 writeb(tmp & ~S3C2410_TICNT_ENABLE, base + S3C2410_TICNT);
411         } else {
412                 /* re-enable the device, and check it is ok */
413
414                 if ((readb(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0){
415                         dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
416
417                         tmp = readb(base + S3C2410_RTCCON);
418                         writeb(tmp|S3C2410_RTCCON_RTCEN, base+S3C2410_RTCCON);
419                 }
420
421                 if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)){
422                         dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
423
424                         tmp = readb(base + S3C2410_RTCCON);
425                         writeb(tmp& ~S3C2410_RTCCON_CNTSEL, base+S3C2410_RTCCON);
426                 }
427
428                 if ((readb(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)){
429                         dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
430
431                         tmp = readb(base + S3C2410_RTCCON);
432                         writeb(tmp & ~S3C2410_RTCCON_CLKRST, base+S3C2410_RTCCON);
433                 }
434         }
435 }
436
437 static int s3c_rtc_remove(struct platform_device *dev)
438 {
439         struct rtc_device *rtc = platform_get_drvdata(dev);
440
441         platform_set_drvdata(dev, NULL);
442         rtc_device_unregister(rtc);
443
444         s3c_rtc_setpie(0);
445         s3c_rtc_setaie(0);
446
447         iounmap(s3c_rtc_base);
448         release_resource(s3c_rtc_mem);
449         kfree(s3c_rtc_mem);
450
451         return 0;
452 }
453
454 static int s3c_rtc_probe(struct platform_device *pdev)
455 {
456         struct rtc_device *rtc;
457         struct resource *res;
458         int ret;
459
460         pr_debug("%s: probe=%p\n", __FUNCTION__, pdev);
461
462         /* find the IRQs */
463
464         s3c_rtc_tickno = platform_get_irq(pdev, 1);
465         if (s3c_rtc_tickno < 0) {
466                 dev_err(&pdev->dev, "no irq for rtc tick\n");
467                 return -ENOENT;
468         }
469
470         s3c_rtc_alarmno = platform_get_irq(pdev, 0);
471         if (s3c_rtc_alarmno < 0) {
472                 dev_err(&pdev->dev, "no irq for alarm\n");
473                 return -ENOENT;
474         }
475
476         pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
477                  s3c_rtc_tickno, s3c_rtc_alarmno);
478
479         /* get the memory region */
480
481         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
482         if (res == NULL) {
483                 dev_err(&pdev->dev, "failed to get memory region resource\n");
484                 return -ENOENT;
485         }
486
487         s3c_rtc_mem = request_mem_region(res->start,
488                                          res->end-res->start+1,
489                                          pdev->name);
490
491         if (s3c_rtc_mem == NULL) {
492                 dev_err(&pdev->dev, "failed to reserve memory region\n");
493                 ret = -ENOENT;
494                 goto err_nores;
495         }
496
497         s3c_rtc_base = ioremap(res->start, res->end - res->start + 1);
498         if (s3c_rtc_base == NULL) {
499                 dev_err(&pdev->dev, "failed ioremap()\n");
500                 ret = -EINVAL;
501                 goto err_nomap;
502         }
503
504         /* check to see if everything is setup correctly */
505
506         s3c_rtc_enable(pdev, 1);
507
508         pr_debug("s3c2410_rtc: RTCCON=%02x\n",
509                  readb(s3c_rtc_base + S3C2410_RTCCON));
510
511         s3c_rtc_setfreq(s3c_rtc_freq);
512
513         /* register RTC and exit */
514
515         rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
516                                   THIS_MODULE);
517
518         if (IS_ERR(rtc)) {
519                 dev_err(&pdev->dev, "cannot attach rtc\n");
520                 ret = PTR_ERR(rtc);
521                 goto err_nortc;
522         }
523
524         rtc->max_user_freq = 128;
525
526         platform_set_drvdata(pdev, rtc);
527         return 0;
528
529  err_nortc:
530         s3c_rtc_enable(pdev, 0);
531         iounmap(s3c_rtc_base);
532
533  err_nomap:
534         release_resource(s3c_rtc_mem);
535
536  err_nores:
537         return ret;
538 }
539
540 #ifdef CONFIG_PM
541
542 /* RTC Power management control */
543
544 static int ticnt_save;
545
546 static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
547 {
548         /* save TICNT for anyone using periodic interrupts */
549         ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
550         s3c_rtc_enable(pdev, 0);
551         return 0;
552 }
553
554 static int s3c_rtc_resume(struct platform_device *pdev)
555 {
556         s3c_rtc_enable(pdev, 1);
557         writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
558         return 0;
559 }
560 #else
561 #define s3c_rtc_suspend NULL
562 #define s3c_rtc_resume  NULL
563 #endif
564
565 static struct platform_driver s3c2410_rtcdrv = {
566         .probe          = s3c_rtc_probe,
567         .remove         = s3c_rtc_remove,
568         .suspend        = s3c_rtc_suspend,
569         .resume         = s3c_rtc_resume,
570         .driver         = {
571                 .name   = "s3c2410-rtc",
572                 .owner  = THIS_MODULE,
573         },
574 };
575
576 static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
577
578 static int __init s3c_rtc_init(void)
579 {
580         printk(banner);
581         return platform_driver_register(&s3c2410_rtcdrv);
582 }
583
584 static void __exit s3c_rtc_exit(void)
585 {
586         platform_driver_unregister(&s3c2410_rtcdrv);
587 }
588
589 module_init(s3c_rtc_init);
590 module_exit(s3c_rtc_exit);
591
592 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
593 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
594 MODULE_LICENSE("GPL");