xref: /openbmc/linux/drivers/rtc/rtc-s3c.c (revision df687341)
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 
35 struct 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 	const 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;
53 	int ticnt_en_save;
54 	bool wake_en;
55 };
56 
57 struct s3c_rtc_data {
58 	int max_user_freq;
59 	bool needs_src_clk;
60 
61 	void (*irq_handler) (struct s3c_rtc *info, int mask);
62 	void (*set_freq) (struct s3c_rtc *info, int freq);
63 	void (*enable_tick) (struct s3c_rtc *info, struct seq_file *seq);
64 	void (*select_tick_clk) (struct s3c_rtc *info);
65 	void (*save_tick_cnt) (struct s3c_rtc *info);
66 	void (*restore_tick_cnt) (struct s3c_rtc *info);
67 	void (*enable) (struct s3c_rtc *info);
68 	void (*disable) (struct s3c_rtc *info);
69 };
70 
71 static int s3c_rtc_enable_clk(struct s3c_rtc *info)
72 {
73 	unsigned long irq_flags;
74 	int ret = 0;
75 
76 	spin_lock_irqsave(&info->alarm_clk_lock, irq_flags);
77 
78 	if (info->clk_disabled) {
79 		ret = clk_enable(info->rtc_clk);
80 		if (ret)
81 			goto out;
82 
83 		if (info->data->needs_src_clk) {
84 			ret = clk_enable(info->rtc_src_clk);
85 			if (ret) {
86 				clk_disable(info->rtc_clk);
87 				goto out;
88 			}
89 		}
90 		info->clk_disabled = false;
91 	}
92 
93 out:
94 	spin_unlock_irqrestore(&info->alarm_clk_lock, irq_flags);
95 
96 	return ret;
97 }
98 
99 static void s3c_rtc_disable_clk(struct s3c_rtc *info)
100 {
101 	unsigned long irq_flags;
102 
103 	spin_lock_irqsave(&info->alarm_clk_lock, irq_flags);
104 	if (!info->clk_disabled) {
105 		if (info->data->needs_src_clk)
106 			clk_disable(info->rtc_src_clk);
107 		clk_disable(info->rtc_clk);
108 		info->clk_disabled = true;
109 	}
110 	spin_unlock_irqrestore(&info->alarm_clk_lock, irq_flags);
111 }
112 
113 /* IRQ Handlers */
114 static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
115 {
116 	struct s3c_rtc *info = (struct s3c_rtc *)id;
117 
118 	if (info->data->irq_handler)
119 		info->data->irq_handler(info, S3C2410_INTP_TIC);
120 
121 	return IRQ_HANDLED;
122 }
123 
124 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
125 {
126 	struct s3c_rtc *info = (struct s3c_rtc *)id;
127 
128 	if (info->data->irq_handler)
129 		info->data->irq_handler(info, S3C2410_INTP_ALM);
130 
131 	return IRQ_HANDLED;
132 }
133 
134 /* Update control registers */
135 static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
136 {
137 	struct s3c_rtc *info = dev_get_drvdata(dev);
138 	unsigned int tmp;
139 	int ret;
140 
141 	dev_dbg(info->dev, "%s: aie=%d\n", __func__, enabled);
142 
143 	ret = s3c_rtc_enable_clk(info);
144 	if (ret)
145 		return ret;
146 
147 	tmp = readb(info->base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
148 
149 	if (enabled)
150 		tmp |= S3C2410_RTCALM_ALMEN;
151 
152 	writeb(tmp, info->base + S3C2410_RTCALM);
153 
154 	s3c_rtc_disable_clk(info);
155 
156 	if (enabled) {
157 		ret = s3c_rtc_enable_clk(info);
158 		if (ret)
159 			return ret;
160 	} else {
161 		s3c_rtc_disable_clk(info);
162 	}
163 
164 	return 0;
165 }
166 
167 /* Set RTC frequency */
168 static int s3c_rtc_setfreq(struct s3c_rtc *info, int freq)
169 {
170 	int ret;
171 
172 	if (!is_power_of_2(freq))
173 		return -EINVAL;
174 
175 	ret = s3c_rtc_enable_clk(info);
176 	if (ret)
177 		return ret;
178 	spin_lock_irq(&info->pie_lock);
179 
180 	if (info->data->set_freq)
181 		info->data->set_freq(info, freq);
182 
183 	spin_unlock_irq(&info->pie_lock);
184 	s3c_rtc_disable_clk(info);
185 
186 	return 0;
187 }
188 
189 /* Time read/write */
190 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
191 {
192 	struct s3c_rtc *info = dev_get_drvdata(dev);
193 	unsigned int have_retried = 0;
194 	int ret;
195 
196 	ret = s3c_rtc_enable_clk(info);
197 	if (ret)
198 		return ret;
199 
200 retry_get_time:
201 	rtc_tm->tm_min  = readb(info->base + S3C2410_RTCMIN);
202 	rtc_tm->tm_hour = readb(info->base + S3C2410_RTCHOUR);
203 	rtc_tm->tm_mday = readb(info->base + S3C2410_RTCDATE);
204 	rtc_tm->tm_mon  = readb(info->base + S3C2410_RTCMON);
205 	rtc_tm->tm_year = readb(info->base + S3C2410_RTCYEAR);
206 	rtc_tm->tm_sec  = readb(info->base + S3C2410_RTCSEC);
207 
208 	/* the only way to work out whether the system was mid-update
209 	 * when we read it is to check the second counter, and if it
210 	 * is zero, then we re-try the entire read
211 	 */
212 
213 	if (rtc_tm->tm_sec == 0 && !have_retried) {
214 		have_retried = 1;
215 		goto retry_get_time;
216 	}
217 
218 	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
219 	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
220 	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
221 	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
222 	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
223 	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
224 
225 	s3c_rtc_disable_clk(info);
226 
227 	rtc_tm->tm_year += 100;
228 	rtc_tm->tm_mon -= 1;
229 
230 	dev_dbg(dev, "read time %ptR\n", rtc_tm);
231 	return 0;
232 }
233 
234 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
235 {
236 	struct s3c_rtc *info = dev_get_drvdata(dev);
237 	int year = tm->tm_year - 100;
238 	int ret;
239 
240 	dev_dbg(dev, "set time %ptR\n", tm);
241 
242 	/* we get around y2k by simply not supporting it */
243 
244 	if (year < 0 || year >= 100) {
245 		dev_err(dev, "rtc only supports 100 years\n");
246 		return -EINVAL;
247 	}
248 
249 	ret = s3c_rtc_enable_clk(info);
250 	if (ret)
251 		return ret;
252 
253 	writeb(bin2bcd(tm->tm_sec),  info->base + S3C2410_RTCSEC);
254 	writeb(bin2bcd(tm->tm_min),  info->base + S3C2410_RTCMIN);
255 	writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_RTCHOUR);
256 	writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_RTCDATE);
257 	writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_RTCMON);
258 	writeb(bin2bcd(year), info->base + S3C2410_RTCYEAR);
259 
260 	s3c_rtc_disable_clk(info);
261 
262 	return 0;
263 }
264 
265 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
266 {
267 	struct s3c_rtc *info = dev_get_drvdata(dev);
268 	struct rtc_time *alm_tm = &alrm->time;
269 	unsigned int alm_en;
270 	int ret;
271 
272 	ret = s3c_rtc_enable_clk(info);
273 	if (ret)
274 		return ret;
275 
276 	alm_tm->tm_sec  = readb(info->base + S3C2410_ALMSEC);
277 	alm_tm->tm_min  = readb(info->base + S3C2410_ALMMIN);
278 	alm_tm->tm_hour = readb(info->base + S3C2410_ALMHOUR);
279 	alm_tm->tm_mon  = readb(info->base + S3C2410_ALMMON);
280 	alm_tm->tm_mday = readb(info->base + S3C2410_ALMDATE);
281 	alm_tm->tm_year = readb(info->base + S3C2410_ALMYEAR);
282 
283 	alm_en = readb(info->base + S3C2410_RTCALM);
284 
285 	s3c_rtc_disable_clk(info);
286 
287 	alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
288 
289 	dev_dbg(dev, "read alarm %d, %ptR\n", alm_en, alm_tm);
290 
291 	/* decode the alarm enable field */
292 	if (alm_en & S3C2410_RTCALM_SECEN)
293 		alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
294 
295 	if (alm_en & S3C2410_RTCALM_MINEN)
296 		alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
297 
298 	if (alm_en & S3C2410_RTCALM_HOUREN)
299 		alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
300 
301 	if (alm_en & S3C2410_RTCALM_DAYEN)
302 		alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
303 
304 	if (alm_en & S3C2410_RTCALM_MONEN) {
305 		alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
306 		alm_tm->tm_mon -= 1;
307 	}
308 
309 	if (alm_en & S3C2410_RTCALM_YEAREN)
310 		alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
311 
312 	return 0;
313 }
314 
315 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
316 {
317 	struct s3c_rtc *info = dev_get_drvdata(dev);
318 	struct rtc_time *tm = &alrm->time;
319 	unsigned int alrm_en;
320 	int ret;
321 
322 	dev_dbg(dev, "s3c_rtc_setalarm: %d, %ptR\n", alrm->enabled, tm);
323 
324 	ret = s3c_rtc_enable_clk(info);
325 	if (ret)
326 		return ret;
327 
328 	alrm_en = readb(info->base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
329 	writeb(0x00, info->base + S3C2410_RTCALM);
330 
331 	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
332 		alrm_en |= S3C2410_RTCALM_SECEN;
333 		writeb(bin2bcd(tm->tm_sec), info->base + S3C2410_ALMSEC);
334 	}
335 
336 	if (tm->tm_min < 60 && tm->tm_min >= 0) {
337 		alrm_en |= S3C2410_RTCALM_MINEN;
338 		writeb(bin2bcd(tm->tm_min), info->base + S3C2410_ALMMIN);
339 	}
340 
341 	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
342 		alrm_en |= S3C2410_RTCALM_HOUREN;
343 		writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_ALMHOUR);
344 	}
345 
346 	if (tm->tm_mon < 12 && tm->tm_mon >= 0) {
347 		alrm_en |= S3C2410_RTCALM_MONEN;
348 		writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_ALMMON);
349 	}
350 
351 	if (tm->tm_mday <= 31 && tm->tm_mday >= 1) {
352 		alrm_en |= S3C2410_RTCALM_DAYEN;
353 		writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_ALMDATE);
354 	}
355 
356 	dev_dbg(dev, "setting S3C2410_RTCALM to %08x\n", alrm_en);
357 
358 	writeb(alrm_en, info->base + S3C2410_RTCALM);
359 
360 	s3c_rtc_disable_clk(info);
361 
362 	s3c_rtc_setaie(dev, alrm->enabled);
363 
364 	return 0;
365 }
366 
367 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
368 {
369 	struct s3c_rtc *info = dev_get_drvdata(dev);
370 	int ret;
371 
372 	ret = s3c_rtc_enable_clk(info);
373 	if (ret)
374 		return ret;
375 
376 	if (info->data->enable_tick)
377 		info->data->enable_tick(info, seq);
378 
379 	s3c_rtc_disable_clk(info);
380 
381 	return 0;
382 }
383 
384 static const struct rtc_class_ops s3c_rtcops = {
385 	.read_time	= s3c_rtc_gettime,
386 	.set_time	= s3c_rtc_settime,
387 	.read_alarm	= s3c_rtc_getalarm,
388 	.set_alarm	= s3c_rtc_setalarm,
389 	.proc		= s3c_rtc_proc,
390 	.alarm_irq_enable = s3c_rtc_setaie,
391 };
392 
393 static void s3c24xx_rtc_enable(struct s3c_rtc *info)
394 {
395 	unsigned int con, tmp;
396 
397 	con = readw(info->base + S3C2410_RTCCON);
398 	/* re-enable the device, and check it is ok */
399 	if ((con & S3C2410_RTCCON_RTCEN) == 0) {
400 		dev_info(info->dev, "rtc disabled, re-enabling\n");
401 
402 		tmp = readw(info->base + S3C2410_RTCCON);
403 		writew(tmp | S3C2410_RTCCON_RTCEN, info->base + S3C2410_RTCCON);
404 	}
405 
406 	if (con & S3C2410_RTCCON_CNTSEL) {
407 		dev_info(info->dev, "removing RTCCON_CNTSEL\n");
408 
409 		tmp = readw(info->base + S3C2410_RTCCON);
410 		writew(tmp & ~S3C2410_RTCCON_CNTSEL,
411 		       info->base + S3C2410_RTCCON);
412 	}
413 
414 	if (con & S3C2410_RTCCON_CLKRST) {
415 		dev_info(info->dev, "removing RTCCON_CLKRST\n");
416 
417 		tmp = readw(info->base + S3C2410_RTCCON);
418 		writew(tmp & ~S3C2410_RTCCON_CLKRST,
419 		       info->base + S3C2410_RTCCON);
420 	}
421 }
422 
423 static void s3c24xx_rtc_disable(struct s3c_rtc *info)
424 {
425 	unsigned int con;
426 
427 	con = readw(info->base + S3C2410_RTCCON);
428 	con &= ~S3C2410_RTCCON_RTCEN;
429 	writew(con, info->base + S3C2410_RTCCON);
430 
431 	con = readb(info->base + S3C2410_TICNT);
432 	con &= ~S3C2410_TICNT_ENABLE;
433 	writeb(con, info->base + S3C2410_TICNT);
434 }
435 
436 static void s3c6410_rtc_disable(struct s3c_rtc *info)
437 {
438 	unsigned int con;
439 
440 	con = readw(info->base + S3C2410_RTCCON);
441 	con &= ~S3C64XX_RTCCON_TICEN;
442 	con &= ~S3C2410_RTCCON_RTCEN;
443 	writew(con, info->base + S3C2410_RTCCON);
444 }
445 
446 static int s3c_rtc_remove(struct platform_device *pdev)
447 {
448 	struct s3c_rtc *info = platform_get_drvdata(pdev);
449 
450 	s3c_rtc_setaie(info->dev, 0);
451 
452 	if (info->data->needs_src_clk)
453 		clk_unprepare(info->rtc_src_clk);
454 	clk_unprepare(info->rtc_clk);
455 
456 	return 0;
457 }
458 
459 static const struct of_device_id s3c_rtc_dt_match[];
460 
461 static const struct s3c_rtc_data *s3c_rtc_get_data(struct platform_device *pdev)
462 {
463 	const struct of_device_id *match;
464 
465 	match = of_match_node(s3c_rtc_dt_match, pdev->dev.of_node);
466 	return match->data;
467 }
468 
469 static int s3c_rtc_probe(struct platform_device *pdev)
470 {
471 	struct s3c_rtc *info = NULL;
472 	struct rtc_time rtc_tm;
473 	struct resource *res;
474 	int ret;
475 
476 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
477 	if (!info)
478 		return -ENOMEM;
479 
480 	/* find the IRQs */
481 	info->irq_tick = platform_get_irq(pdev, 1);
482 	if (info->irq_tick < 0) {
483 		dev_err(&pdev->dev, "no irq for rtc tick\n");
484 		return info->irq_tick;
485 	}
486 
487 	info->dev = &pdev->dev;
488 	info->data = s3c_rtc_get_data(pdev);
489 	if (!info->data) {
490 		dev_err(&pdev->dev, "failed getting s3c_rtc_data\n");
491 		return -EINVAL;
492 	}
493 	spin_lock_init(&info->pie_lock);
494 	spin_lock_init(&info->alarm_clk_lock);
495 
496 	platform_set_drvdata(pdev, info);
497 
498 	info->irq_alarm = platform_get_irq(pdev, 0);
499 	if (info->irq_alarm < 0) {
500 		dev_err(&pdev->dev, "no irq for alarm\n");
501 		return info->irq_alarm;
502 	}
503 
504 	dev_dbg(&pdev->dev, "s3c2410_rtc: tick irq %d, alarm irq %d\n",
505 		info->irq_tick, info->irq_alarm);
506 
507 	/* get the memory region */
508 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
509 	info->base = devm_ioremap_resource(&pdev->dev, res);
510 	if (IS_ERR(info->base))
511 		return PTR_ERR(info->base);
512 
513 	info->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
514 	if (IS_ERR(info->rtc_clk)) {
515 		ret = PTR_ERR(info->rtc_clk);
516 		if (ret != -EPROBE_DEFER)
517 			dev_err(&pdev->dev, "failed to find rtc clock\n");
518 		else
519 			dev_dbg(&pdev->dev, "probe deferred due to missing rtc clk\n");
520 		return ret;
521 	}
522 	ret = clk_prepare_enable(info->rtc_clk);
523 	if (ret)
524 		return ret;
525 
526 	if (info->data->needs_src_clk) {
527 		info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
528 		if (IS_ERR(info->rtc_src_clk)) {
529 			ret = PTR_ERR(info->rtc_src_clk);
530 			if (ret != -EPROBE_DEFER)
531 				dev_err(&pdev->dev,
532 					"failed to find rtc source clock\n");
533 			else
534 				dev_dbg(&pdev->dev,
535 					"probe deferred due to missing rtc src clk\n");
536 			goto err_src_clk;
537 		}
538 		ret = clk_prepare_enable(info->rtc_src_clk);
539 		if (ret)
540 			goto err_src_clk;
541 	}
542 
543 	/* check to see if everything is setup correctly */
544 	if (info->data->enable)
545 		info->data->enable(info);
546 
547 	dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n",
548 		readw(info->base + S3C2410_RTCCON));
549 
550 	device_init_wakeup(&pdev->dev, 1);
551 
552 	/* Check RTC Time */
553 	if (s3c_rtc_gettime(&pdev->dev, &rtc_tm)) {
554 		rtc_tm.tm_year	= 100;
555 		rtc_tm.tm_mon	= 0;
556 		rtc_tm.tm_mday	= 1;
557 		rtc_tm.tm_hour	= 0;
558 		rtc_tm.tm_min	= 0;
559 		rtc_tm.tm_sec	= 0;
560 
561 		s3c_rtc_settime(&pdev->dev, &rtc_tm);
562 
563 		dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
564 	}
565 
566 	/* register RTC and exit */
567 	info->rtc = devm_rtc_device_register(&pdev->dev, "s3c", &s3c_rtcops,
568 					     THIS_MODULE);
569 	if (IS_ERR(info->rtc)) {
570 		dev_err(&pdev->dev, "cannot attach rtc\n");
571 		ret = PTR_ERR(info->rtc);
572 		goto err_nortc;
573 	}
574 
575 	ret = devm_request_irq(&pdev->dev, info->irq_alarm, s3c_rtc_alarmirq,
576 			       0, "s3c2410-rtc alarm", info);
577 	if (ret) {
578 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_alarm, ret);
579 		goto err_nortc;
580 	}
581 
582 	ret = devm_request_irq(&pdev->dev, info->irq_tick, s3c_rtc_tickirq,
583 			       0, "s3c2410-rtc tick", info);
584 	if (ret) {
585 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_tick, ret);
586 		goto err_nortc;
587 	}
588 
589 	if (info->data->select_tick_clk)
590 		info->data->select_tick_clk(info);
591 
592 	s3c_rtc_setfreq(info, 1);
593 
594 	return 0;
595 
596 err_nortc:
597 	if (info->data->disable)
598 		info->data->disable(info);
599 
600 	if (info->data->needs_src_clk)
601 		clk_disable_unprepare(info->rtc_src_clk);
602 err_src_clk:
603 	clk_disable_unprepare(info->rtc_clk);
604 
605 	return ret;
606 }
607 
608 #ifdef CONFIG_PM_SLEEP
609 
610 static int s3c_rtc_suspend(struct device *dev)
611 {
612 	struct s3c_rtc *info = dev_get_drvdata(dev);
613 	int ret;
614 
615 	ret = s3c_rtc_enable_clk(info);
616 	if (ret)
617 		return ret;
618 
619 	/* save TICNT for anyone using periodic interrupts */
620 	if (info->data->save_tick_cnt)
621 		info->data->save_tick_cnt(info);
622 
623 	if (info->data->disable)
624 		info->data->disable(info);
625 
626 	if (device_may_wakeup(dev) && !info->wake_en) {
627 		if (enable_irq_wake(info->irq_alarm) == 0)
628 			info->wake_en = true;
629 		else
630 			dev_err(dev, "enable_irq_wake failed\n");
631 	}
632 
633 	return 0;
634 }
635 
636 static int s3c_rtc_resume(struct device *dev)
637 {
638 	struct s3c_rtc *info = dev_get_drvdata(dev);
639 
640 	if (info->data->enable)
641 		info->data->enable(info);
642 
643 	if (info->data->restore_tick_cnt)
644 		info->data->restore_tick_cnt(info);
645 
646 	s3c_rtc_disable_clk(info);
647 
648 	if (device_may_wakeup(dev) && info->wake_en) {
649 		disable_irq_wake(info->irq_alarm);
650 		info->wake_en = false;
651 	}
652 
653 	return 0;
654 }
655 #endif
656 static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume);
657 
658 static void s3c24xx_rtc_irq(struct s3c_rtc *info, int mask)
659 {
660 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
661 }
662 
663 static void s3c6410_rtc_irq(struct s3c_rtc *info, int mask)
664 {
665 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
666 	writeb(mask, info->base + S3C2410_INTP);
667 }
668 
669 static void s3c2410_rtc_setfreq(struct s3c_rtc *info, int freq)
670 {
671 	unsigned int tmp = 0;
672 	int val;
673 
674 	tmp = readb(info->base + S3C2410_TICNT);
675 	tmp &= S3C2410_TICNT_ENABLE;
676 
677 	val = (info->rtc->max_user_freq / freq) - 1;
678 	tmp |= val;
679 
680 	writel(tmp, info->base + S3C2410_TICNT);
681 }
682 
683 static void s3c2416_rtc_setfreq(struct s3c_rtc *info, int freq)
684 {
685 	unsigned int tmp = 0;
686 	int val;
687 
688 	tmp = readb(info->base + S3C2410_TICNT);
689 	tmp &= S3C2410_TICNT_ENABLE;
690 
691 	val = (info->rtc->max_user_freq / freq) - 1;
692 
693 	tmp |= S3C2443_TICNT_PART(val);
694 	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
695 
696 	writel(S3C2416_TICNT2_PART(val), info->base + S3C2416_TICNT2);
697 
698 	writel(tmp, info->base + S3C2410_TICNT);
699 }
700 
701 static void s3c2443_rtc_setfreq(struct s3c_rtc *info, int freq)
702 {
703 	unsigned int tmp = 0;
704 	int val;
705 
706 	tmp = readb(info->base + S3C2410_TICNT);
707 	tmp &= S3C2410_TICNT_ENABLE;
708 
709 	val = (info->rtc->max_user_freq / freq) - 1;
710 
711 	tmp |= S3C2443_TICNT_PART(val);
712 	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
713 
714 	writel(tmp, info->base + S3C2410_TICNT);
715 }
716 
717 static void s3c6410_rtc_setfreq(struct s3c_rtc *info, int freq)
718 {
719 	int val;
720 
721 	val = (info->rtc->max_user_freq / freq) - 1;
722 	writel(val, info->base + S3C2410_TICNT);
723 }
724 
725 static void s3c24xx_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
726 {
727 	unsigned int ticnt;
728 
729 	ticnt = readb(info->base + S3C2410_TICNT);
730 	ticnt &= S3C2410_TICNT_ENABLE;
731 
732 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
733 }
734 
735 static void s3c2416_rtc_select_tick_clk(struct s3c_rtc *info)
736 {
737 	unsigned int con;
738 
739 	con = readw(info->base + S3C2410_RTCCON);
740 	con |= S3C2443_RTCCON_TICSEL;
741 	writew(con, info->base + S3C2410_RTCCON);
742 }
743 
744 static void s3c6410_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
745 {
746 	unsigned int ticnt;
747 
748 	ticnt = readw(info->base + S3C2410_RTCCON);
749 	ticnt &= S3C64XX_RTCCON_TICEN;
750 
751 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
752 }
753 
754 static void s3c24xx_rtc_save_tick_cnt(struct s3c_rtc *info)
755 {
756 	info->ticnt_save = readb(info->base + S3C2410_TICNT);
757 }
758 
759 static void s3c24xx_rtc_restore_tick_cnt(struct s3c_rtc *info)
760 {
761 	writeb(info->ticnt_save, info->base + S3C2410_TICNT);
762 }
763 
764 static void s3c6410_rtc_save_tick_cnt(struct s3c_rtc *info)
765 {
766 	info->ticnt_en_save = readw(info->base + S3C2410_RTCCON);
767 	info->ticnt_en_save &= S3C64XX_RTCCON_TICEN;
768 	info->ticnt_save = readl(info->base + S3C2410_TICNT);
769 }
770 
771 static void s3c6410_rtc_restore_tick_cnt(struct s3c_rtc *info)
772 {
773 	unsigned int con;
774 
775 	writel(info->ticnt_save, info->base + S3C2410_TICNT);
776 	if (info->ticnt_en_save) {
777 		con = readw(info->base + S3C2410_RTCCON);
778 		writew(con | info->ticnt_en_save, info->base + S3C2410_RTCCON);
779 	}
780 }
781 
782 static struct s3c_rtc_data const s3c2410_rtc_data = {
783 	.max_user_freq		= 128,
784 	.irq_handler		= s3c24xx_rtc_irq,
785 	.set_freq		= s3c2410_rtc_setfreq,
786 	.enable_tick		= s3c24xx_rtc_enable_tick,
787 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
788 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
789 	.enable			= s3c24xx_rtc_enable,
790 	.disable		= s3c24xx_rtc_disable,
791 };
792 
793 static struct s3c_rtc_data const s3c2416_rtc_data = {
794 	.max_user_freq		= 32768,
795 	.irq_handler		= s3c24xx_rtc_irq,
796 	.set_freq		= s3c2416_rtc_setfreq,
797 	.enable_tick		= s3c24xx_rtc_enable_tick,
798 	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
799 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
800 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
801 	.enable			= s3c24xx_rtc_enable,
802 	.disable		= s3c24xx_rtc_disable,
803 };
804 
805 static struct s3c_rtc_data const s3c2443_rtc_data = {
806 	.max_user_freq		= 32768,
807 	.irq_handler		= s3c24xx_rtc_irq,
808 	.set_freq		= s3c2443_rtc_setfreq,
809 	.enable_tick		= s3c24xx_rtc_enable_tick,
810 	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
811 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
812 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
813 	.enable			= s3c24xx_rtc_enable,
814 	.disable		= s3c24xx_rtc_disable,
815 };
816 
817 static struct s3c_rtc_data const s3c6410_rtc_data = {
818 	.max_user_freq		= 32768,
819 	.needs_src_clk		= true,
820 	.irq_handler		= s3c6410_rtc_irq,
821 	.set_freq		= s3c6410_rtc_setfreq,
822 	.enable_tick		= s3c6410_rtc_enable_tick,
823 	.save_tick_cnt		= s3c6410_rtc_save_tick_cnt,
824 	.restore_tick_cnt	= s3c6410_rtc_restore_tick_cnt,
825 	.enable			= s3c24xx_rtc_enable,
826 	.disable		= s3c6410_rtc_disable,
827 };
828 
829 static const struct of_device_id s3c_rtc_dt_match[] = {
830 	{
831 		.compatible = "samsung,s3c2410-rtc",
832 		.data = &s3c2410_rtc_data,
833 	}, {
834 		.compatible = "samsung,s3c2416-rtc",
835 		.data = &s3c2416_rtc_data,
836 	}, {
837 		.compatible = "samsung,s3c2443-rtc",
838 		.data = &s3c2443_rtc_data,
839 	}, {
840 		.compatible = "samsung,s3c6410-rtc",
841 		.data = &s3c6410_rtc_data,
842 	}, {
843 		.compatible = "samsung,exynos3250-rtc",
844 		.data = &s3c6410_rtc_data,
845 	},
846 	{ /* sentinel */ },
847 };
848 MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
849 
850 static struct platform_driver s3c_rtc_driver = {
851 	.probe		= s3c_rtc_probe,
852 	.remove		= s3c_rtc_remove,
853 	.driver		= {
854 		.name	= "s3c-rtc",
855 		.pm	= &s3c_rtc_pm_ops,
856 		.of_match_table	= of_match_ptr(s3c_rtc_dt_match),
857 	},
858 };
859 module_platform_driver(s3c_rtc_driver);
860 
861 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
862 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
863 MODULE_LICENSE("GPL");
864 MODULE_ALIAS("platform:s3c2410-rtc");
865