1/* drivers/rtc/rtc-s3c.c
2 *
3 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
4 *		http://www.samsung.com/
5 *
6 * Copyright (c) 2004,2006 Simtec Electronics
7 *	Ben Dooks, <ben@simtec.co.uk>
8 *	http://armlinux.simtec.co.uk/
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 *
14 * S3C2410/S3C2440/S3C24XX Internal RTC Driver
15*/
16
17#include <linux/module.h>
18#include <linux/fs.h>
19#include <linux/string.h>
20#include <linux/init.h>
21#include <linux/platform_device.h>
22#include <linux/interrupt.h>
23#include <linux/rtc.h>
24#include <linux/bcd.h>
25#include <linux/clk.h>
26#include <linux/log2.h>
27#include <linux/slab.h>
28#include <linux/of.h>
29#include <linux/uaccess.h>
30#include <linux/io.h>
31
32#include <asm/irq.h>
33#include "rtc-s3c.h"
34
35struct s3c_rtc {
36	struct device *dev;
37	struct rtc_device *rtc;
38
39	void __iomem *base;
40	struct clk *rtc_clk;
41	struct clk *rtc_src_clk;
42	bool clk_disabled;
43
44	struct s3c_rtc_data *data;
45
46	int irq_alarm;
47	int irq_tick;
48
49	spinlock_t pie_lock;
50	spinlock_t alarm_clk_lock;
51
52	int ticnt_save, ticnt_en_save;
53	bool wake_en;
54};
55
56struct s3c_rtc_data {
57	int max_user_freq;
58	bool needs_src_clk;
59
60	void (*irq_handler) (struct s3c_rtc *info, int mask);
61	void (*set_freq) (struct s3c_rtc *info, int freq);
62	void (*enable_tick) (struct s3c_rtc *info, struct seq_file *seq);
63	void (*select_tick_clk) (struct s3c_rtc *info);
64	void (*save_tick_cnt) (struct s3c_rtc *info);
65	void (*restore_tick_cnt) (struct s3c_rtc *info);
66	void (*enable) (struct s3c_rtc *info);
67	void (*disable) (struct s3c_rtc *info);
68};
69
70static void s3c_rtc_enable_clk(struct s3c_rtc *info)
71{
72	unsigned long irq_flags;
73
74	spin_lock_irqsave(&info->alarm_clk_lock, irq_flags);
75	if (info->clk_disabled) {
76		clk_enable(info->rtc_clk);
77		if (info->data->needs_src_clk)
78			clk_enable(info->rtc_src_clk);
79		info->clk_disabled = false;
80	}
81	spin_unlock_irqrestore(&info->alarm_clk_lock, irq_flags);
82}
83
84static void s3c_rtc_disable_clk(struct s3c_rtc *info)
85{
86	unsigned long irq_flags;
87
88	spin_lock_irqsave(&info->alarm_clk_lock, irq_flags);
89	if (!info->clk_disabled) {
90		if (info->data->needs_src_clk)
91			clk_disable(info->rtc_src_clk);
92		clk_disable(info->rtc_clk);
93		info->clk_disabled = true;
94	}
95	spin_unlock_irqrestore(&info->alarm_clk_lock, irq_flags);
96}
97
98/* IRQ Handlers */
99static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
100{
101	struct s3c_rtc *info = (struct s3c_rtc *)id;
102
103	if (info->data->irq_handler)
104		info->data->irq_handler(info, S3C2410_INTP_TIC);
105
106	return IRQ_HANDLED;
107}
108
109static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
110{
111	struct s3c_rtc *info = (struct s3c_rtc *)id;
112
113	if (info->data->irq_handler)
114		info->data->irq_handler(info, S3C2410_INTP_ALM);
115
116	return IRQ_HANDLED;
117}
118
119/* Update control registers */
120static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
121{
122	struct s3c_rtc *info = dev_get_drvdata(dev);
123	unsigned int tmp;
124
125	dev_dbg(info->dev, "%s: aie=%d\n", __func__, enabled);
126
127	s3c_rtc_enable_clk(info);
128
129	tmp = readb(info->base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
130
131	if (enabled)
132		tmp |= S3C2410_RTCALM_ALMEN;
133
134	writeb(tmp, info->base + S3C2410_RTCALM);
135
136	s3c_rtc_disable_clk(info);
137
138	if (enabled)
139		s3c_rtc_enable_clk(info);
140	else
141		s3c_rtc_disable_clk(info);
142
143	return 0;
144}
145
146/* Set RTC frequency */
147static int s3c_rtc_setfreq(struct s3c_rtc *info, int freq)
148{
149	if (!is_power_of_2(freq))
150		return -EINVAL;
151
152	spin_lock_irq(&info->pie_lock);
153
154	if (info->data->set_freq)
155		info->data->set_freq(info, freq);
156
157	spin_unlock_irq(&info->pie_lock);
158
159	return 0;
160}
161
162/* Time read/write */
163static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
164{
165	struct s3c_rtc *info = dev_get_drvdata(dev);
166	unsigned int have_retried = 0;
167
168	s3c_rtc_enable_clk(info);
169
170 retry_get_time:
171	rtc_tm->tm_min  = readb(info->base + S3C2410_RTCMIN);
172	rtc_tm->tm_hour = readb(info->base + S3C2410_RTCHOUR);
173	rtc_tm->tm_mday = readb(info->base + S3C2410_RTCDATE);
174	rtc_tm->tm_mon  = readb(info->base + S3C2410_RTCMON);
175	rtc_tm->tm_year = readb(info->base + S3C2410_RTCYEAR);
176	rtc_tm->tm_sec  = readb(info->base + S3C2410_RTCSEC);
177
178	/* the only way to work out whether the system was mid-update
179	 * when we read it is to check the second counter, and if it
180	 * is zero, then we re-try the entire read
181	 */
182
183	if (rtc_tm->tm_sec == 0 && !have_retried) {
184		have_retried = 1;
185		goto retry_get_time;
186	}
187
188	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
189	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
190	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
191	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
192	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
193	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
194
195	s3c_rtc_disable_clk(info);
196
197	rtc_tm->tm_year += 100;
198
199	dev_dbg(dev, "read time %04d.%02d.%02d %02d:%02d:%02d\n",
200		 1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
201		 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
202
203	rtc_tm->tm_mon -= 1;
204
205	return rtc_valid_tm(rtc_tm);
206}
207
208static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
209{
210	struct s3c_rtc *info = dev_get_drvdata(dev);
211	int year = tm->tm_year - 100;
212
213	dev_dbg(dev, "set time %04d.%02d.%02d %02d:%02d:%02d\n",
214		 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
215		 tm->tm_hour, tm->tm_min, tm->tm_sec);
216
217	/* we get around y2k by simply not supporting it */
218
219	if (year < 0 || year >= 100) {
220		dev_err(dev, "rtc only supports 100 years\n");
221		return -EINVAL;
222	}
223
224	s3c_rtc_enable_clk(info);
225
226	writeb(bin2bcd(tm->tm_sec),  info->base + S3C2410_RTCSEC);
227	writeb(bin2bcd(tm->tm_min),  info->base + S3C2410_RTCMIN);
228	writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_RTCHOUR);
229	writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_RTCDATE);
230	writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_RTCMON);
231	writeb(bin2bcd(year), info->base + S3C2410_RTCYEAR);
232
233	s3c_rtc_disable_clk(info);
234
235	return 0;
236}
237
238static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
239{
240	struct s3c_rtc *info = dev_get_drvdata(dev);
241	struct rtc_time *alm_tm = &alrm->time;
242	unsigned int alm_en;
243
244	s3c_rtc_enable_clk(info);
245
246	alm_tm->tm_sec  = readb(info->base + S3C2410_ALMSEC);
247	alm_tm->tm_min  = readb(info->base + S3C2410_ALMMIN);
248	alm_tm->tm_hour = readb(info->base + S3C2410_ALMHOUR);
249	alm_tm->tm_mon  = readb(info->base + S3C2410_ALMMON);
250	alm_tm->tm_mday = readb(info->base + S3C2410_ALMDATE);
251	alm_tm->tm_year = readb(info->base + S3C2410_ALMYEAR);
252
253	alm_en = readb(info->base + S3C2410_RTCALM);
254
255	s3c_rtc_disable_clk(info);
256
257	alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
258
259	dev_dbg(dev, "read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
260		 alm_en,
261		 1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
262		 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
263
264	/* decode the alarm enable field */
265	if (alm_en & S3C2410_RTCALM_SECEN)
266		alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
267	else
268		alm_tm->tm_sec = -1;
269
270	if (alm_en & S3C2410_RTCALM_MINEN)
271		alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
272	else
273		alm_tm->tm_min = -1;
274
275	if (alm_en & S3C2410_RTCALM_HOUREN)
276		alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
277	else
278		alm_tm->tm_hour = -1;
279
280	if (alm_en & S3C2410_RTCALM_DAYEN)
281		alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
282	else
283		alm_tm->tm_mday = -1;
284
285	if (alm_en & S3C2410_RTCALM_MONEN) {
286		alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
287		alm_tm->tm_mon -= 1;
288	} else {
289		alm_tm->tm_mon = -1;
290	}
291
292	if (alm_en & S3C2410_RTCALM_YEAREN)
293		alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
294	else
295		alm_tm->tm_year = -1;
296
297	return 0;
298}
299
300static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
301{
302	struct s3c_rtc *info = dev_get_drvdata(dev);
303	struct rtc_time *tm = &alrm->time;
304	unsigned int alrm_en;
305
306	dev_dbg(dev, "s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
307		 alrm->enabled,
308		 1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
309		 tm->tm_hour, tm->tm_min, tm->tm_sec);
310
311	s3c_rtc_enable_clk(info);
312
313	alrm_en = readb(info->base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
314	writeb(0x00, info->base + S3C2410_RTCALM);
315
316	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
317		alrm_en |= S3C2410_RTCALM_SECEN;
318		writeb(bin2bcd(tm->tm_sec), info->base + S3C2410_ALMSEC);
319	}
320
321	if (tm->tm_min < 60 && tm->tm_min >= 0) {
322		alrm_en |= S3C2410_RTCALM_MINEN;
323		writeb(bin2bcd(tm->tm_min), info->base + S3C2410_ALMMIN);
324	}
325
326	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
327		alrm_en |= S3C2410_RTCALM_HOUREN;
328		writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_ALMHOUR);
329	}
330
331	dev_dbg(dev, "setting S3C2410_RTCALM to %08x\n", alrm_en);
332
333	writeb(alrm_en, info->base + S3C2410_RTCALM);
334
335	s3c_rtc_disable_clk(info);
336
337	s3c_rtc_setaie(dev, alrm->enabled);
338
339	return 0;
340}
341
342static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
343{
344	struct s3c_rtc *info = dev_get_drvdata(dev);
345
346	s3c_rtc_enable_clk(info);
347
348	if (info->data->enable_tick)
349		info->data->enable_tick(info, seq);
350
351	s3c_rtc_disable_clk(info);
352
353	return 0;
354}
355
356static const struct rtc_class_ops s3c_rtcops = {
357	.read_time	= s3c_rtc_gettime,
358	.set_time	= s3c_rtc_settime,
359	.read_alarm	= s3c_rtc_getalarm,
360	.set_alarm	= s3c_rtc_setalarm,
361	.proc		= s3c_rtc_proc,
362	.alarm_irq_enable = s3c_rtc_setaie,
363};
364
365static void s3c24xx_rtc_enable(struct s3c_rtc *info)
366{
367	unsigned int con, tmp;
368
369	con = readw(info->base + S3C2410_RTCCON);
370	/* re-enable the device, and check it is ok */
371	if ((con & S3C2410_RTCCON_RTCEN) == 0) {
372		dev_info(info->dev, "rtc disabled, re-enabling\n");
373
374		tmp = readw(info->base + S3C2410_RTCCON);
375		writew(tmp | S3C2410_RTCCON_RTCEN,
376			info->base + S3C2410_RTCCON);
377	}
378
379	if (con & S3C2410_RTCCON_CNTSEL) {
380		dev_info(info->dev, "removing RTCCON_CNTSEL\n");
381
382		tmp = readw(info->base + S3C2410_RTCCON);
383		writew(tmp & ~S3C2410_RTCCON_CNTSEL,
384			info->base + S3C2410_RTCCON);
385	}
386
387	if (con & S3C2410_RTCCON_CLKRST) {
388		dev_info(info->dev, "removing RTCCON_CLKRST\n");
389
390		tmp = readw(info->base + S3C2410_RTCCON);
391		writew(tmp & ~S3C2410_RTCCON_CLKRST,
392			info->base + S3C2410_RTCCON);
393	}
394}
395
396static void s3c24xx_rtc_disable(struct s3c_rtc *info)
397{
398	unsigned int con;
399
400	con = readw(info->base + S3C2410_RTCCON);
401	con &= ~S3C2410_RTCCON_RTCEN;
402	writew(con, info->base + S3C2410_RTCCON);
403
404	con = readb(info->base + S3C2410_TICNT);
405	con &= ~S3C2410_TICNT_ENABLE;
406	writeb(con, info->base + S3C2410_TICNT);
407}
408
409static void s3c6410_rtc_disable(struct s3c_rtc *info)
410{
411	unsigned int con;
412
413	con = readw(info->base + S3C2410_RTCCON);
414	con &= ~S3C64XX_RTCCON_TICEN;
415	con &= ~S3C2410_RTCCON_RTCEN;
416	writew(con, info->base + S3C2410_RTCCON);
417}
418
419static int s3c_rtc_remove(struct platform_device *pdev)
420{
421	struct s3c_rtc *info = platform_get_drvdata(pdev);
422
423	s3c_rtc_setaie(info->dev, 0);
424
425	clk_unprepare(info->rtc_clk);
426	info->rtc_clk = NULL;
427
428	return 0;
429}
430
431static const struct of_device_id s3c_rtc_dt_match[];
432
433static struct s3c_rtc_data *s3c_rtc_get_data(struct platform_device *pdev)
434{
435	const struct of_device_id *match;
436
437	match = of_match_node(s3c_rtc_dt_match, pdev->dev.of_node);
438	return (struct s3c_rtc_data *)match->data;
439}
440
441static int s3c_rtc_probe(struct platform_device *pdev)
442{
443	struct s3c_rtc *info = NULL;
444	struct rtc_time rtc_tm;
445	struct resource *res;
446	int ret;
447
448	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
449	if (!info)
450		return -ENOMEM;
451
452	/* find the IRQs */
453	info->irq_tick = platform_get_irq(pdev, 1);
454	if (info->irq_tick < 0) {
455		dev_err(&pdev->dev, "no irq for rtc tick\n");
456		return info->irq_tick;
457	}
458
459	info->dev = &pdev->dev;
460	info->data = s3c_rtc_get_data(pdev);
461	if (!info->data) {
462		dev_err(&pdev->dev, "failed getting s3c_rtc_data\n");
463		return -EINVAL;
464	}
465	spin_lock_init(&info->pie_lock);
466	spin_lock_init(&info->alarm_clk_lock);
467
468	platform_set_drvdata(pdev, info);
469
470	info->irq_alarm = platform_get_irq(pdev, 0);
471	if (info->irq_alarm < 0) {
472		dev_err(&pdev->dev, "no irq for alarm\n");
473		return info->irq_alarm;
474	}
475
476	dev_dbg(&pdev->dev, "s3c2410_rtc: tick irq %d, alarm irq %d\n",
477		 info->irq_tick, info->irq_alarm);
478
479	/* get the memory region */
480	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
481	info->base = devm_ioremap_resource(&pdev->dev, res);
482	if (IS_ERR(info->base))
483		return PTR_ERR(info->base);
484
485	info->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
486	if (IS_ERR(info->rtc_clk)) {
487		dev_err(&pdev->dev, "failed to find rtc clock\n");
488		return PTR_ERR(info->rtc_clk);
489	}
490	clk_prepare_enable(info->rtc_clk);
491
492	if (info->data->needs_src_clk) {
493		info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
494		if (IS_ERR(info->rtc_src_clk)) {
495			dev_err(&pdev->dev,
496				"failed to find rtc source clock\n");
497			return PTR_ERR(info->rtc_src_clk);
498		}
499		clk_prepare_enable(info->rtc_src_clk);
500	}
501
502	/* check to see if everything is setup correctly */
503	if (info->data->enable)
504		info->data->enable(info);
505
506	dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n",
507		 readw(info->base + S3C2410_RTCCON));
508
509	device_init_wakeup(&pdev->dev, 1);
510
511	/* Check RTC Time */
512	if (s3c_rtc_gettime(&pdev->dev, &rtc_tm)) {
513		rtc_tm.tm_year	= 100;
514		rtc_tm.tm_mon	= 0;
515		rtc_tm.tm_mday	= 1;
516		rtc_tm.tm_hour	= 0;
517		rtc_tm.tm_min	= 0;
518		rtc_tm.tm_sec	= 0;
519
520		s3c_rtc_settime(&pdev->dev, &rtc_tm);
521
522		dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
523	}
524
525	/* register RTC and exit */
526	info->rtc = devm_rtc_device_register(&pdev->dev, "s3c", &s3c_rtcops,
527				  THIS_MODULE);
528	if (IS_ERR(info->rtc)) {
529		dev_err(&pdev->dev, "cannot attach rtc\n");
530		ret = PTR_ERR(info->rtc);
531		goto err_nortc;
532	}
533
534	ret = devm_request_irq(&pdev->dev, info->irq_alarm, s3c_rtc_alarmirq,
535			  0,  "s3c2410-rtc alarm", info);
536	if (ret) {
537		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_alarm, ret);
538		goto err_nortc;
539	}
540
541	ret = devm_request_irq(&pdev->dev, info->irq_tick, s3c_rtc_tickirq,
542			  0,  "s3c2410-rtc tick", info);
543	if (ret) {
544		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_tick, ret);
545		goto err_nortc;
546	}
547
548	if (info->data->select_tick_clk)
549		info->data->select_tick_clk(info);
550
551	s3c_rtc_setfreq(info, 1);
552
553	s3c_rtc_disable_clk(info);
554
555	return 0;
556
557 err_nortc:
558	if (info->data->disable)
559		info->data->disable(info);
560
561	if (info->data->needs_src_clk)
562		clk_disable_unprepare(info->rtc_src_clk);
563	clk_disable_unprepare(info->rtc_clk);
564
565	return ret;
566}
567
568#ifdef CONFIG_PM_SLEEP
569
570static int s3c_rtc_suspend(struct device *dev)
571{
572	struct s3c_rtc *info = dev_get_drvdata(dev);
573
574	s3c_rtc_enable_clk(info);
575
576	/* save TICNT for anyone using periodic interrupts */
577	if (info->data->save_tick_cnt)
578		info->data->save_tick_cnt(info);
579
580	if (info->data->disable)
581		info->data->disable(info);
582
583	if (device_may_wakeup(dev) && !info->wake_en) {
584		if (enable_irq_wake(info->irq_alarm) == 0)
585			info->wake_en = true;
586		else
587			dev_err(dev, "enable_irq_wake failed\n");
588	}
589
590	return 0;
591}
592
593static int s3c_rtc_resume(struct device *dev)
594{
595	struct s3c_rtc *info = dev_get_drvdata(dev);
596
597	if (info->data->enable)
598		info->data->enable(info);
599
600	if (info->data->restore_tick_cnt)
601		info->data->restore_tick_cnt(info);
602
603	s3c_rtc_disable_clk(info);
604
605	if (device_may_wakeup(dev) && info->wake_en) {
606		disable_irq_wake(info->irq_alarm);
607		info->wake_en = false;
608	}
609
610	return 0;
611}
612#endif
613static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume);
614
615static void s3c24xx_rtc_irq(struct s3c_rtc *info, int mask)
616{
617	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
618}
619
620static void s3c6410_rtc_irq(struct s3c_rtc *info, int mask)
621{
622	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
623	writeb(mask, info->base + S3C2410_INTP);
624}
625
626static void s3c2410_rtc_setfreq(struct s3c_rtc *info, int freq)
627{
628	unsigned int tmp = 0;
629	int val;
630
631	tmp = readb(info->base + S3C2410_TICNT);
632	tmp &= S3C2410_TICNT_ENABLE;
633
634	val = (info->rtc->max_user_freq / freq) - 1;
635	tmp |= val;
636
637	writel(tmp, info->base + S3C2410_TICNT);
638}
639
640static void s3c2416_rtc_setfreq(struct s3c_rtc *info, int freq)
641{
642	unsigned int tmp = 0;
643	int val;
644
645	tmp = readb(info->base + S3C2410_TICNT);
646	tmp &= S3C2410_TICNT_ENABLE;
647
648	val = (info->rtc->max_user_freq / freq) - 1;
649
650	tmp |= S3C2443_TICNT_PART(val);
651	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
652
653	writel(S3C2416_TICNT2_PART(val), info->base + S3C2416_TICNT2);
654
655	writel(tmp, info->base + S3C2410_TICNT);
656}
657
658static void s3c2443_rtc_setfreq(struct s3c_rtc *info, int freq)
659{
660	unsigned int tmp = 0;
661	int val;
662
663	tmp = readb(info->base + S3C2410_TICNT);
664	tmp &= S3C2410_TICNT_ENABLE;
665
666	val = (info->rtc->max_user_freq / freq) - 1;
667
668	tmp |= S3C2443_TICNT_PART(val);
669	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
670
671	writel(tmp, info->base + S3C2410_TICNT);
672}
673
674static void s3c6410_rtc_setfreq(struct s3c_rtc *info, int freq)
675{
676	int val;
677
678	val = (info->rtc->max_user_freq / freq) - 1;
679	writel(val, info->base + S3C2410_TICNT);
680}
681
682static void s3c24xx_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
683{
684	unsigned int ticnt;
685
686	ticnt = readb(info->base + S3C2410_TICNT);
687	ticnt &= S3C2410_TICNT_ENABLE;
688
689	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
690}
691
692static void s3c2416_rtc_select_tick_clk(struct s3c_rtc *info)
693{
694	unsigned int con;
695
696	con = readw(info->base + S3C2410_RTCCON);
697	con |= S3C2443_RTCCON_TICSEL;
698	writew(con, info->base + S3C2410_RTCCON);
699}
700
701static void s3c6410_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
702{
703	unsigned int ticnt;
704
705	ticnt = readw(info->base + S3C2410_RTCCON);
706	ticnt &= S3C64XX_RTCCON_TICEN;
707
708	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
709}
710
711static void s3c24xx_rtc_save_tick_cnt(struct s3c_rtc *info)
712{
713	info->ticnt_save = readb(info->base + S3C2410_TICNT);
714}
715
716static void s3c24xx_rtc_restore_tick_cnt(struct s3c_rtc *info)
717{
718	writeb(info->ticnt_save, info->base + S3C2410_TICNT);
719}
720
721static void s3c6410_rtc_save_tick_cnt(struct s3c_rtc *info)
722{
723	info->ticnt_en_save = readw(info->base + S3C2410_RTCCON);
724	info->ticnt_en_save &= S3C64XX_RTCCON_TICEN;
725	info->ticnt_save = readl(info->base + S3C2410_TICNT);
726}
727
728static void s3c6410_rtc_restore_tick_cnt(struct s3c_rtc *info)
729{
730	unsigned int con;
731
732	writel(info->ticnt_save, info->base + S3C2410_TICNT);
733	if (info->ticnt_en_save) {
734		con = readw(info->base + S3C2410_RTCCON);
735		writew(con | info->ticnt_en_save,
736				info->base + S3C2410_RTCCON);
737	}
738}
739
740static struct s3c_rtc_data const s3c2410_rtc_data = {
741	.max_user_freq		= 128,
742	.irq_handler		= s3c24xx_rtc_irq,
743	.set_freq		= s3c2410_rtc_setfreq,
744	.enable_tick		= s3c24xx_rtc_enable_tick,
745	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
746	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
747	.enable			= s3c24xx_rtc_enable,
748	.disable		= s3c24xx_rtc_disable,
749};
750
751static struct s3c_rtc_data const s3c2416_rtc_data = {
752	.max_user_freq		= 32768,
753	.irq_handler		= s3c24xx_rtc_irq,
754	.set_freq		= s3c2416_rtc_setfreq,
755	.enable_tick		= s3c24xx_rtc_enable_tick,
756	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
757	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
758	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
759	.enable			= s3c24xx_rtc_enable,
760	.disable		= s3c24xx_rtc_disable,
761};
762
763static struct s3c_rtc_data const s3c2443_rtc_data = {
764	.max_user_freq		= 32768,
765	.irq_handler		= s3c24xx_rtc_irq,
766	.set_freq		= s3c2443_rtc_setfreq,
767	.enable_tick		= s3c24xx_rtc_enable_tick,
768	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
769	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
770	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
771	.enable			= s3c24xx_rtc_enable,
772	.disable		= s3c24xx_rtc_disable,
773};
774
775static struct s3c_rtc_data const s3c6410_rtc_data = {
776	.max_user_freq		= 32768,
777	.needs_src_clk		= true,
778	.irq_handler		= s3c6410_rtc_irq,
779	.set_freq		= s3c6410_rtc_setfreq,
780	.enable_tick		= s3c6410_rtc_enable_tick,
781	.save_tick_cnt		= s3c6410_rtc_save_tick_cnt,
782	.restore_tick_cnt	= s3c6410_rtc_restore_tick_cnt,
783	.enable			= s3c24xx_rtc_enable,
784	.disable		= s3c6410_rtc_disable,
785};
786
787static struct s3c_rtc_data const exynos3250_rtc_data = {
788	.max_user_freq		= 32768,
789	.needs_src_clk		= true,
790	.irq_handler		= s3c6410_rtc_irq,
791	.set_freq		= s3c6410_rtc_setfreq,
792	.enable_tick		= s3c6410_rtc_enable_tick,
793	.save_tick_cnt		= s3c6410_rtc_save_tick_cnt,
794	.restore_tick_cnt	= s3c6410_rtc_restore_tick_cnt,
795	.enable			= s3c24xx_rtc_enable,
796	.disable		= s3c6410_rtc_disable,
797};
798
799static const struct of_device_id s3c_rtc_dt_match[] = {
800	{
801		.compatible = "samsung,s3c2410-rtc",
802		.data = (void *)&s3c2410_rtc_data,
803	}, {
804		.compatible = "samsung,s3c2416-rtc",
805		.data = (void *)&s3c2416_rtc_data,
806	}, {
807		.compatible = "samsung,s3c2443-rtc",
808		.data = (void *)&s3c2443_rtc_data,
809	}, {
810		.compatible = "samsung,s3c6410-rtc",
811		.data = (void *)&s3c6410_rtc_data,
812	}, {
813		.compatible = "samsung,exynos3250-rtc",
814		.data = (void *)&exynos3250_rtc_data,
815	},
816	{ /* sentinel */ },
817};
818MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
819
820static struct platform_driver s3c_rtc_driver = {
821	.probe		= s3c_rtc_probe,
822	.remove		= s3c_rtc_remove,
823	.driver		= {
824		.name	= "s3c-rtc",
825		.pm	= &s3c_rtc_pm_ops,
826		.of_match_table	= of_match_ptr(s3c_rtc_dt_match),
827	},
828};
829module_platform_driver(s3c_rtc_driver);
830
831MODULE_DESCRIPTION("Samsung S3C RTC Driver");
832MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
833MODULE_LICENSE("GPL");
834MODULE_ALIAS("platform:s3c2410-rtc");
835