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