xref: /linux/drivers/rtc/rtc-s3c.c (revision b6ebbac51bedf9e98e837688bc838f400196da5e)
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 	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 
56 struct 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 
70 static 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 
84 static 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 */
99 static 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 
109 static 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 */
120 static 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 */
147 static int s3c_rtc_setfreq(struct s3c_rtc *info, int freq)
148 {
149 	if (!is_power_of_2(freq))
150 		return -EINVAL;
151 
152 	s3c_rtc_enable_clk(info);
153 	spin_lock_irq(&info->pie_lock);
154 
155 	if (info->data->set_freq)
156 		info->data->set_freq(info, freq);
157 
158 	spin_unlock_irq(&info->pie_lock);
159 	s3c_rtc_disable_clk(info);
160 
161 	return 0;
162 }
163 
164 /* Time read/write */
165 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
166 {
167 	struct s3c_rtc *info = dev_get_drvdata(dev);
168 	unsigned int have_retried = 0;
169 
170 	s3c_rtc_enable_clk(info);
171 
172  retry_get_time:
173 	rtc_tm->tm_min  = readb(info->base + S3C2410_RTCMIN);
174 	rtc_tm->tm_hour = readb(info->base + S3C2410_RTCHOUR);
175 	rtc_tm->tm_mday = readb(info->base + S3C2410_RTCDATE);
176 	rtc_tm->tm_mon  = readb(info->base + S3C2410_RTCMON);
177 	rtc_tm->tm_year = readb(info->base + S3C2410_RTCYEAR);
178 	rtc_tm->tm_sec  = readb(info->base + S3C2410_RTCSEC);
179 
180 	/* the only way to work out whether the system was mid-update
181 	 * when we read it is to check the second counter, and if it
182 	 * is zero, then we re-try the entire read
183 	 */
184 
185 	if (rtc_tm->tm_sec == 0 && !have_retried) {
186 		have_retried = 1;
187 		goto retry_get_time;
188 	}
189 
190 	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
191 	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
192 	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
193 	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
194 	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
195 	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
196 
197 	s3c_rtc_disable_clk(info);
198 
199 	rtc_tm->tm_year += 100;
200 
201 	dev_dbg(dev, "read time %04d.%02d.%02d %02d:%02d:%02d\n",
202 		 1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
203 		 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
204 
205 	rtc_tm->tm_mon -= 1;
206 
207 	return rtc_valid_tm(rtc_tm);
208 }
209 
210 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
211 {
212 	struct s3c_rtc *info = dev_get_drvdata(dev);
213 	int year = tm->tm_year - 100;
214 
215 	dev_dbg(dev, "set time %04d.%02d.%02d %02d:%02d:%02d\n",
216 		 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
217 		 tm->tm_hour, tm->tm_min, tm->tm_sec);
218 
219 	/* we get around y2k by simply not supporting it */
220 
221 	if (year < 0 || year >= 100) {
222 		dev_err(dev, "rtc only supports 100 years\n");
223 		return -EINVAL;
224 	}
225 
226 	s3c_rtc_enable_clk(info);
227 
228 	writeb(bin2bcd(tm->tm_sec),  info->base + S3C2410_RTCSEC);
229 	writeb(bin2bcd(tm->tm_min),  info->base + S3C2410_RTCMIN);
230 	writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_RTCHOUR);
231 	writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_RTCDATE);
232 	writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_RTCMON);
233 	writeb(bin2bcd(year), info->base + S3C2410_RTCYEAR);
234 
235 	s3c_rtc_disable_clk(info);
236 
237 	return 0;
238 }
239 
240 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
241 {
242 	struct s3c_rtc *info = dev_get_drvdata(dev);
243 	struct rtc_time *alm_tm = &alrm->time;
244 	unsigned int alm_en;
245 
246 	s3c_rtc_enable_clk(info);
247 
248 	alm_tm->tm_sec  = readb(info->base + S3C2410_ALMSEC);
249 	alm_tm->tm_min  = readb(info->base + S3C2410_ALMMIN);
250 	alm_tm->tm_hour = readb(info->base + S3C2410_ALMHOUR);
251 	alm_tm->tm_mon  = readb(info->base + S3C2410_ALMMON);
252 	alm_tm->tm_mday = readb(info->base + S3C2410_ALMDATE);
253 	alm_tm->tm_year = readb(info->base + S3C2410_ALMYEAR);
254 
255 	alm_en = readb(info->base + S3C2410_RTCALM);
256 
257 	s3c_rtc_disable_clk(info);
258 
259 	alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
260 
261 	dev_dbg(dev, "read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
262 		 alm_en,
263 		 1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
264 		 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
265 
266 	/* decode the alarm enable field */
267 	if (alm_en & S3C2410_RTCALM_SECEN)
268 		alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
269 
270 	if (alm_en & S3C2410_RTCALM_MINEN)
271 		alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
272 
273 	if (alm_en & S3C2410_RTCALM_HOUREN)
274 		alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
275 
276 	if (alm_en & S3C2410_RTCALM_DAYEN)
277 		alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
278 
279 	if (alm_en & S3C2410_RTCALM_MONEN) {
280 		alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
281 		alm_tm->tm_mon -= 1;
282 	}
283 
284 	if (alm_en & S3C2410_RTCALM_YEAREN)
285 		alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
286 
287 	return 0;
288 }
289 
290 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
291 {
292 	struct s3c_rtc *info = dev_get_drvdata(dev);
293 	struct rtc_time *tm = &alrm->time;
294 	unsigned int alrm_en;
295 	int year = tm->tm_year - 100;
296 
297 	dev_dbg(dev, "s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
298 		 alrm->enabled,
299 		 1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
300 		 tm->tm_hour, tm->tm_min, tm->tm_sec);
301 
302 	s3c_rtc_enable_clk(info);
303 
304 	alrm_en = readb(info->base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
305 	writeb(0x00, info->base + S3C2410_RTCALM);
306 
307 	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
308 		alrm_en |= S3C2410_RTCALM_SECEN;
309 		writeb(bin2bcd(tm->tm_sec), info->base + S3C2410_ALMSEC);
310 	}
311 
312 	if (tm->tm_min < 60 && tm->tm_min >= 0) {
313 		alrm_en |= S3C2410_RTCALM_MINEN;
314 		writeb(bin2bcd(tm->tm_min), info->base + S3C2410_ALMMIN);
315 	}
316 
317 	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
318 		alrm_en |= S3C2410_RTCALM_HOUREN;
319 		writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_ALMHOUR);
320 	}
321 
322 	if (year < 100 && year >= 0) {
323 		alrm_en |= S3C2410_RTCALM_YEAREN;
324 		writeb(bin2bcd(year), info->base + S3C2410_ALMYEAR);
325 	}
326 
327 	if (tm->tm_mon < 12 && tm->tm_mon >= 0) {
328 		alrm_en |= S3C2410_RTCALM_MONEN;
329 		writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_ALMMON);
330 	}
331 
332 	if (tm->tm_mday <= 31 && tm->tm_mday >= 1) {
333 		alrm_en |= S3C2410_RTCALM_DAYEN;
334 		writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_ALMDATE);
335 	}
336 
337 	dev_dbg(dev, "setting S3C2410_RTCALM to %08x\n", alrm_en);
338 
339 	writeb(alrm_en, info->base + S3C2410_RTCALM);
340 
341 	s3c_rtc_disable_clk(info);
342 
343 	s3c_rtc_setaie(dev, alrm->enabled);
344 
345 	return 0;
346 }
347 
348 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
349 {
350 	struct s3c_rtc *info = dev_get_drvdata(dev);
351 
352 	s3c_rtc_enable_clk(info);
353 
354 	if (info->data->enable_tick)
355 		info->data->enable_tick(info, seq);
356 
357 	s3c_rtc_disable_clk(info);
358 
359 	return 0;
360 }
361 
362 static const struct rtc_class_ops s3c_rtcops = {
363 	.read_time	= s3c_rtc_gettime,
364 	.set_time	= s3c_rtc_settime,
365 	.read_alarm	= s3c_rtc_getalarm,
366 	.set_alarm	= s3c_rtc_setalarm,
367 	.proc		= s3c_rtc_proc,
368 	.alarm_irq_enable = s3c_rtc_setaie,
369 };
370 
371 static void s3c24xx_rtc_enable(struct s3c_rtc *info)
372 {
373 	unsigned int con, tmp;
374 
375 	con = readw(info->base + S3C2410_RTCCON);
376 	/* re-enable the device, and check it is ok */
377 	if ((con & S3C2410_RTCCON_RTCEN) == 0) {
378 		dev_info(info->dev, "rtc disabled, re-enabling\n");
379 
380 		tmp = readw(info->base + S3C2410_RTCCON);
381 		writew(tmp | S3C2410_RTCCON_RTCEN,
382 			info->base + S3C2410_RTCCON);
383 	}
384 
385 	if (con & S3C2410_RTCCON_CNTSEL) {
386 		dev_info(info->dev, "removing RTCCON_CNTSEL\n");
387 
388 		tmp = readw(info->base + S3C2410_RTCCON);
389 		writew(tmp & ~S3C2410_RTCCON_CNTSEL,
390 			info->base + S3C2410_RTCCON);
391 	}
392 
393 	if (con & S3C2410_RTCCON_CLKRST) {
394 		dev_info(info->dev, "removing RTCCON_CLKRST\n");
395 
396 		tmp = readw(info->base + S3C2410_RTCCON);
397 		writew(tmp & ~S3C2410_RTCCON_CLKRST,
398 			info->base + S3C2410_RTCCON);
399 	}
400 }
401 
402 static void s3c24xx_rtc_disable(struct s3c_rtc *info)
403 {
404 	unsigned int con;
405 
406 	con = readw(info->base + S3C2410_RTCCON);
407 	con &= ~S3C2410_RTCCON_RTCEN;
408 	writew(con, info->base + S3C2410_RTCCON);
409 
410 	con = readb(info->base + S3C2410_TICNT);
411 	con &= ~S3C2410_TICNT_ENABLE;
412 	writeb(con, info->base + S3C2410_TICNT);
413 }
414 
415 static void s3c6410_rtc_disable(struct s3c_rtc *info)
416 {
417 	unsigned int con;
418 
419 	con = readw(info->base + S3C2410_RTCCON);
420 	con &= ~S3C64XX_RTCCON_TICEN;
421 	con &= ~S3C2410_RTCCON_RTCEN;
422 	writew(con, info->base + S3C2410_RTCCON);
423 }
424 
425 static int s3c_rtc_remove(struct platform_device *pdev)
426 {
427 	struct s3c_rtc *info = platform_get_drvdata(pdev);
428 
429 	s3c_rtc_setaie(info->dev, 0);
430 
431 	if (info->data->needs_src_clk)
432 		clk_unprepare(info->rtc_src_clk);
433 	clk_unprepare(info->rtc_clk);
434 
435 	return 0;
436 }
437 
438 static const struct of_device_id s3c_rtc_dt_match[];
439 
440 static struct s3c_rtc_data *s3c_rtc_get_data(struct platform_device *pdev)
441 {
442 	const struct of_device_id *match;
443 
444 	match = of_match_node(s3c_rtc_dt_match, pdev->dev.of_node);
445 	return (struct s3c_rtc_data *)match->data;
446 }
447 
448 static int s3c_rtc_probe(struct platform_device *pdev)
449 {
450 	struct s3c_rtc *info = NULL;
451 	struct rtc_time rtc_tm;
452 	struct resource *res;
453 	int ret;
454 
455 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
456 	if (!info)
457 		return -ENOMEM;
458 
459 	/* find the IRQs */
460 	info->irq_tick = platform_get_irq(pdev, 1);
461 	if (info->irq_tick < 0) {
462 		dev_err(&pdev->dev, "no irq for rtc tick\n");
463 		return info->irq_tick;
464 	}
465 
466 	info->dev = &pdev->dev;
467 	info->data = s3c_rtc_get_data(pdev);
468 	if (!info->data) {
469 		dev_err(&pdev->dev, "failed getting s3c_rtc_data\n");
470 		return -EINVAL;
471 	}
472 	spin_lock_init(&info->pie_lock);
473 	spin_lock_init(&info->alarm_clk_lock);
474 
475 	platform_set_drvdata(pdev, info);
476 
477 	info->irq_alarm = platform_get_irq(pdev, 0);
478 	if (info->irq_alarm < 0) {
479 		dev_err(&pdev->dev, "no irq for alarm\n");
480 		return info->irq_alarm;
481 	}
482 
483 	dev_dbg(&pdev->dev, "s3c2410_rtc: tick irq %d, alarm irq %d\n",
484 		 info->irq_tick, info->irq_alarm);
485 
486 	/* get the memory region */
487 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
488 	info->base = devm_ioremap_resource(&pdev->dev, res);
489 	if (IS_ERR(info->base))
490 		return PTR_ERR(info->base);
491 
492 	info->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
493 	if (IS_ERR(info->rtc_clk)) {
494 		ret = PTR_ERR(info->rtc_clk);
495 		if (ret != -EPROBE_DEFER)
496 			dev_err(&pdev->dev, "failed to find rtc clock\n");
497 		else
498 			dev_dbg(&pdev->dev, "probe deferred due to missing rtc clk\n");
499 		return ret;
500 	}
501 	clk_prepare_enable(info->rtc_clk);
502 
503 	if (info->data->needs_src_clk) {
504 		info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
505 		if (IS_ERR(info->rtc_src_clk)) {
506 			ret = PTR_ERR(info->rtc_src_clk);
507 			if (ret != -EPROBE_DEFER)
508 				dev_err(&pdev->dev,
509 					"failed to find rtc source clock\n");
510 			else
511 				dev_dbg(&pdev->dev,
512 					"probe deferred due to missing rtc src clk\n");
513 			clk_disable_unprepare(info->rtc_clk);
514 			return ret;
515 		}
516 		clk_prepare_enable(info->rtc_src_clk);
517 	}
518 
519 	/* check to see if everything is setup correctly */
520 	if (info->data->enable)
521 		info->data->enable(info);
522 
523 	dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n",
524 		 readw(info->base + S3C2410_RTCCON));
525 
526 	device_init_wakeup(&pdev->dev, 1);
527 
528 	/* Check RTC Time */
529 	if (s3c_rtc_gettime(&pdev->dev, &rtc_tm)) {
530 		rtc_tm.tm_year	= 100;
531 		rtc_tm.tm_mon	= 0;
532 		rtc_tm.tm_mday	= 1;
533 		rtc_tm.tm_hour	= 0;
534 		rtc_tm.tm_min	= 0;
535 		rtc_tm.tm_sec	= 0;
536 
537 		s3c_rtc_settime(&pdev->dev, &rtc_tm);
538 
539 		dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
540 	}
541 
542 	/* register RTC and exit */
543 	info->rtc = devm_rtc_device_register(&pdev->dev, "s3c", &s3c_rtcops,
544 				  THIS_MODULE);
545 	if (IS_ERR(info->rtc)) {
546 		dev_err(&pdev->dev, "cannot attach rtc\n");
547 		ret = PTR_ERR(info->rtc);
548 		goto err_nortc;
549 	}
550 
551 	ret = devm_request_irq(&pdev->dev, info->irq_alarm, s3c_rtc_alarmirq,
552 			  0,  "s3c2410-rtc alarm", info);
553 	if (ret) {
554 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_alarm, ret);
555 		goto err_nortc;
556 	}
557 
558 	ret = devm_request_irq(&pdev->dev, info->irq_tick, s3c_rtc_tickirq,
559 			  0,  "s3c2410-rtc tick", info);
560 	if (ret) {
561 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_tick, ret);
562 		goto err_nortc;
563 	}
564 
565 	if (info->data->select_tick_clk)
566 		info->data->select_tick_clk(info);
567 
568 	s3c_rtc_setfreq(info, 1);
569 
570 	return 0;
571 
572  err_nortc:
573 	if (info->data->disable)
574 		info->data->disable(info);
575 
576 	if (info->data->needs_src_clk)
577 		clk_disable_unprepare(info->rtc_src_clk);
578 	clk_disable_unprepare(info->rtc_clk);
579 
580 	return ret;
581 }
582 
583 #ifdef CONFIG_PM_SLEEP
584 
585 static int s3c_rtc_suspend(struct device *dev)
586 {
587 	struct s3c_rtc *info = dev_get_drvdata(dev);
588 
589 	s3c_rtc_enable_clk(info);
590 
591 	/* save TICNT for anyone using periodic interrupts */
592 	if (info->data->save_tick_cnt)
593 		info->data->save_tick_cnt(info);
594 
595 	if (info->data->disable)
596 		info->data->disable(info);
597 
598 	if (device_may_wakeup(dev) && !info->wake_en) {
599 		if (enable_irq_wake(info->irq_alarm) == 0)
600 			info->wake_en = true;
601 		else
602 			dev_err(dev, "enable_irq_wake failed\n");
603 	}
604 
605 	return 0;
606 }
607 
608 static int s3c_rtc_resume(struct device *dev)
609 {
610 	struct s3c_rtc *info = dev_get_drvdata(dev);
611 
612 	if (info->data->enable)
613 		info->data->enable(info);
614 
615 	if (info->data->restore_tick_cnt)
616 		info->data->restore_tick_cnt(info);
617 
618 	s3c_rtc_disable_clk(info);
619 
620 	if (device_may_wakeup(dev) && info->wake_en) {
621 		disable_irq_wake(info->irq_alarm);
622 		info->wake_en = false;
623 	}
624 
625 	return 0;
626 }
627 #endif
628 static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume);
629 
630 static void s3c24xx_rtc_irq(struct s3c_rtc *info, int mask)
631 {
632 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
633 }
634 
635 static void s3c6410_rtc_irq(struct s3c_rtc *info, int mask)
636 {
637 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
638 	writeb(mask, info->base + S3C2410_INTP);
639 }
640 
641 static void s3c2410_rtc_setfreq(struct s3c_rtc *info, int freq)
642 {
643 	unsigned int tmp = 0;
644 	int val;
645 
646 	tmp = readb(info->base + S3C2410_TICNT);
647 	tmp &= S3C2410_TICNT_ENABLE;
648 
649 	val = (info->rtc->max_user_freq / freq) - 1;
650 	tmp |= val;
651 
652 	writel(tmp, info->base + S3C2410_TICNT);
653 }
654 
655 static void s3c2416_rtc_setfreq(struct s3c_rtc *info, int freq)
656 {
657 	unsigned int tmp = 0;
658 	int val;
659 
660 	tmp = readb(info->base + S3C2410_TICNT);
661 	tmp &= S3C2410_TICNT_ENABLE;
662 
663 	val = (info->rtc->max_user_freq / freq) - 1;
664 
665 	tmp |= S3C2443_TICNT_PART(val);
666 	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
667 
668 	writel(S3C2416_TICNT2_PART(val), info->base + S3C2416_TICNT2);
669 
670 	writel(tmp, info->base + S3C2410_TICNT);
671 }
672 
673 static void s3c2443_rtc_setfreq(struct s3c_rtc *info, int freq)
674 {
675 	unsigned int tmp = 0;
676 	int val;
677 
678 	tmp = readb(info->base + S3C2410_TICNT);
679 	tmp &= S3C2410_TICNT_ENABLE;
680 
681 	val = (info->rtc->max_user_freq / freq) - 1;
682 
683 	tmp |= S3C2443_TICNT_PART(val);
684 	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
685 
686 	writel(tmp, info->base + S3C2410_TICNT);
687 }
688 
689 static void s3c6410_rtc_setfreq(struct s3c_rtc *info, int freq)
690 {
691 	int val;
692 
693 	val = (info->rtc->max_user_freq / freq) - 1;
694 	writel(val, info->base + S3C2410_TICNT);
695 }
696 
697 static void s3c24xx_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
698 {
699 	unsigned int ticnt;
700 
701 	ticnt = readb(info->base + S3C2410_TICNT);
702 	ticnt &= S3C2410_TICNT_ENABLE;
703 
704 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
705 }
706 
707 static void s3c2416_rtc_select_tick_clk(struct s3c_rtc *info)
708 {
709 	unsigned int con;
710 
711 	con = readw(info->base + S3C2410_RTCCON);
712 	con |= S3C2443_RTCCON_TICSEL;
713 	writew(con, info->base + S3C2410_RTCCON);
714 }
715 
716 static void s3c6410_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
717 {
718 	unsigned int ticnt;
719 
720 	ticnt = readw(info->base + S3C2410_RTCCON);
721 	ticnt &= S3C64XX_RTCCON_TICEN;
722 
723 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
724 }
725 
726 static void s3c24xx_rtc_save_tick_cnt(struct s3c_rtc *info)
727 {
728 	info->ticnt_save = readb(info->base + S3C2410_TICNT);
729 }
730 
731 static void s3c24xx_rtc_restore_tick_cnt(struct s3c_rtc *info)
732 {
733 	writeb(info->ticnt_save, info->base + S3C2410_TICNT);
734 }
735 
736 static void s3c6410_rtc_save_tick_cnt(struct s3c_rtc *info)
737 {
738 	info->ticnt_en_save = readw(info->base + S3C2410_RTCCON);
739 	info->ticnt_en_save &= S3C64XX_RTCCON_TICEN;
740 	info->ticnt_save = readl(info->base + S3C2410_TICNT);
741 }
742 
743 static void s3c6410_rtc_restore_tick_cnt(struct s3c_rtc *info)
744 {
745 	unsigned int con;
746 
747 	writel(info->ticnt_save, info->base + S3C2410_TICNT);
748 	if (info->ticnt_en_save) {
749 		con = readw(info->base + S3C2410_RTCCON);
750 		writew(con | info->ticnt_en_save,
751 				info->base + S3C2410_RTCCON);
752 	}
753 }
754 
755 static struct s3c_rtc_data const s3c2410_rtc_data = {
756 	.max_user_freq		= 128,
757 	.irq_handler		= s3c24xx_rtc_irq,
758 	.set_freq		= s3c2410_rtc_setfreq,
759 	.enable_tick		= s3c24xx_rtc_enable_tick,
760 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
761 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
762 	.enable			= s3c24xx_rtc_enable,
763 	.disable		= s3c24xx_rtc_disable,
764 };
765 
766 static struct s3c_rtc_data const s3c2416_rtc_data = {
767 	.max_user_freq		= 32768,
768 	.irq_handler		= s3c24xx_rtc_irq,
769 	.set_freq		= s3c2416_rtc_setfreq,
770 	.enable_tick		= s3c24xx_rtc_enable_tick,
771 	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
772 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
773 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
774 	.enable			= s3c24xx_rtc_enable,
775 	.disable		= s3c24xx_rtc_disable,
776 };
777 
778 static struct s3c_rtc_data const s3c2443_rtc_data = {
779 	.max_user_freq		= 32768,
780 	.irq_handler		= s3c24xx_rtc_irq,
781 	.set_freq		= s3c2443_rtc_setfreq,
782 	.enable_tick		= s3c24xx_rtc_enable_tick,
783 	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
784 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
785 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
786 	.enable			= s3c24xx_rtc_enable,
787 	.disable		= s3c24xx_rtc_disable,
788 };
789 
790 static struct s3c_rtc_data const s3c6410_rtc_data = {
791 	.max_user_freq		= 32768,
792 	.needs_src_clk		= true,
793 	.irq_handler		= s3c6410_rtc_irq,
794 	.set_freq		= s3c6410_rtc_setfreq,
795 	.enable_tick		= s3c6410_rtc_enable_tick,
796 	.save_tick_cnt		= s3c6410_rtc_save_tick_cnt,
797 	.restore_tick_cnt	= s3c6410_rtc_restore_tick_cnt,
798 	.enable			= s3c24xx_rtc_enable,
799 	.disable		= s3c6410_rtc_disable,
800 };
801 
802 static const struct of_device_id s3c_rtc_dt_match[] = {
803 	{
804 		.compatible = "samsung,s3c2410-rtc",
805 		.data = (void *)&s3c2410_rtc_data,
806 	}, {
807 		.compatible = "samsung,s3c2416-rtc",
808 		.data = (void *)&s3c2416_rtc_data,
809 	}, {
810 		.compatible = "samsung,s3c2443-rtc",
811 		.data = (void *)&s3c2443_rtc_data,
812 	}, {
813 		.compatible = "samsung,s3c6410-rtc",
814 		.data = (void *)&s3c6410_rtc_data,
815 	}, {
816 		.compatible = "samsung,exynos3250-rtc",
817 		.data = (void *)&s3c6410_rtc_data,
818 	},
819 	{ /* sentinel */ },
820 };
821 MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
822 
823 static struct platform_driver s3c_rtc_driver = {
824 	.probe		= s3c_rtc_probe,
825 	.remove		= s3c_rtc_remove,
826 	.driver		= {
827 		.name	= "s3c-rtc",
828 		.pm	= &s3c_rtc_pm_ops,
829 		.of_match_table	= of_match_ptr(s3c_rtc_dt_match),
830 	},
831 };
832 module_platform_driver(s3c_rtc_driver);
833 
834 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
835 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
836 MODULE_LICENSE("GPL");
837 MODULE_ALIAS("platform:s3c2410-rtc");
838