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ARM: OMAP: McBSP: Prepare for splitting into omap1 and omap2 code
[linux-ginger.git] / drivers / rtc / rtc-s3c.c
blobf26e0cad8f167c5221fd5a480c42e7f2fcdb2baa
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", __func__, 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", __func__, 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", __func__, 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");
595 MODULE_ALIAS("platform:s3c2410-rtc");
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