xref: /linux/drivers/rtc/rtc-s3c.c (revision a4cdb556cae05cd3e7b602b3a44c01420c4e2258)
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 	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 */
163 static 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 
208 static 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 
238 static 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 
300 static 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 	int year = tm->tm_year - 100;
306 
307 	dev_dbg(dev, "s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
308 		 alrm->enabled,
309 		 1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
310 		 tm->tm_hour, tm->tm_min, tm->tm_sec);
311 
312 	s3c_rtc_enable_clk(info);
313 
314 	alrm_en = readb(info->base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
315 	writeb(0x00, info->base + S3C2410_RTCALM);
316 
317 	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
318 		alrm_en |= S3C2410_RTCALM_SECEN;
319 		writeb(bin2bcd(tm->tm_sec), info->base + S3C2410_ALMSEC);
320 	}
321 
322 	if (tm->tm_min < 60 && tm->tm_min >= 0) {
323 		alrm_en |= S3C2410_RTCALM_MINEN;
324 		writeb(bin2bcd(tm->tm_min), info->base + S3C2410_ALMMIN);
325 	}
326 
327 	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
328 		alrm_en |= S3C2410_RTCALM_HOUREN;
329 		writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_ALMHOUR);
330 	}
331 
332 	if (year < 100 && year >= 0) {
333 		alrm_en |= S3C2410_RTCALM_YEAREN;
334 		writeb(bin2bcd(year), info->base + S3C2410_ALMYEAR);
335 	}
336 
337 	if (tm->tm_mon < 12 && tm->tm_mon >= 0) {
338 		alrm_en |= S3C2410_RTCALM_MONEN;
339 		writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_ALMMON);
340 	}
341 
342 	if (tm->tm_mday <= 31 && tm->tm_mday >= 1) {
343 		alrm_en |= S3C2410_RTCALM_DAYEN;
344 		writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_ALMDATE);
345 	}
346 
347 	dev_dbg(dev, "setting S3C2410_RTCALM to %08x\n", alrm_en);
348 
349 	writeb(alrm_en, info->base + S3C2410_RTCALM);
350 
351 	s3c_rtc_disable_clk(info);
352 
353 	s3c_rtc_setaie(dev, alrm->enabled);
354 
355 	return 0;
356 }
357 
358 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
359 {
360 	struct s3c_rtc *info = dev_get_drvdata(dev);
361 
362 	s3c_rtc_enable_clk(info);
363 
364 	if (info->data->enable_tick)
365 		info->data->enable_tick(info, seq);
366 
367 	s3c_rtc_disable_clk(info);
368 
369 	return 0;
370 }
371 
372 static const struct rtc_class_ops s3c_rtcops = {
373 	.read_time	= s3c_rtc_gettime,
374 	.set_time	= s3c_rtc_settime,
375 	.read_alarm	= s3c_rtc_getalarm,
376 	.set_alarm	= s3c_rtc_setalarm,
377 	.proc		= s3c_rtc_proc,
378 	.alarm_irq_enable = s3c_rtc_setaie,
379 };
380 
381 static void s3c24xx_rtc_enable(struct s3c_rtc *info)
382 {
383 	unsigned int con, tmp;
384 
385 	con = readw(info->base + S3C2410_RTCCON);
386 	/* re-enable the device, and check it is ok */
387 	if ((con & S3C2410_RTCCON_RTCEN) == 0) {
388 		dev_info(info->dev, "rtc disabled, re-enabling\n");
389 
390 		tmp = readw(info->base + S3C2410_RTCCON);
391 		writew(tmp | S3C2410_RTCCON_RTCEN,
392 			info->base + S3C2410_RTCCON);
393 	}
394 
395 	if (con & S3C2410_RTCCON_CNTSEL) {
396 		dev_info(info->dev, "removing RTCCON_CNTSEL\n");
397 
398 		tmp = readw(info->base + S3C2410_RTCCON);
399 		writew(tmp & ~S3C2410_RTCCON_CNTSEL,
400 			info->base + S3C2410_RTCCON);
401 	}
402 
403 	if (con & S3C2410_RTCCON_CLKRST) {
404 		dev_info(info->dev, "removing RTCCON_CLKRST\n");
405 
406 		tmp = readw(info->base + S3C2410_RTCCON);
407 		writew(tmp & ~S3C2410_RTCCON_CLKRST,
408 			info->base + S3C2410_RTCCON);
409 	}
410 }
411 
412 static void s3c24xx_rtc_disable(struct s3c_rtc *info)
413 {
414 	unsigned int con;
415 
416 	con = readw(info->base + S3C2410_RTCCON);
417 	con &= ~S3C2410_RTCCON_RTCEN;
418 	writew(con, info->base + S3C2410_RTCCON);
419 
420 	con = readb(info->base + S3C2410_TICNT);
421 	con &= ~S3C2410_TICNT_ENABLE;
422 	writeb(con, info->base + S3C2410_TICNT);
423 }
424 
425 static void s3c6410_rtc_disable(struct s3c_rtc *info)
426 {
427 	unsigned int con;
428 
429 	con = readw(info->base + S3C2410_RTCCON);
430 	con &= ~S3C64XX_RTCCON_TICEN;
431 	con &= ~S3C2410_RTCCON_RTCEN;
432 	writew(con, info->base + S3C2410_RTCCON);
433 }
434 
435 static int s3c_rtc_remove(struct platform_device *pdev)
436 {
437 	struct s3c_rtc *info = platform_get_drvdata(pdev);
438 
439 	s3c_rtc_setaie(info->dev, 0);
440 
441 	if (info->data->needs_src_clk)
442 		clk_unprepare(info->rtc_src_clk);
443 	clk_unprepare(info->rtc_clk);
444 
445 	return 0;
446 }
447 
448 static const struct of_device_id s3c_rtc_dt_match[];
449 
450 static struct s3c_rtc_data *s3c_rtc_get_data(struct platform_device *pdev)
451 {
452 	const struct of_device_id *match;
453 
454 	match = of_match_node(s3c_rtc_dt_match, pdev->dev.of_node);
455 	return (struct s3c_rtc_data *)match->data;
456 }
457 
458 static int s3c_rtc_probe(struct platform_device *pdev)
459 {
460 	struct s3c_rtc *info = NULL;
461 	struct rtc_time rtc_tm;
462 	struct resource *res;
463 	int ret;
464 
465 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
466 	if (!info)
467 		return -ENOMEM;
468 
469 	/* find the IRQs */
470 	info->irq_tick = platform_get_irq(pdev, 1);
471 	if (info->irq_tick < 0) {
472 		dev_err(&pdev->dev, "no irq for rtc tick\n");
473 		return info->irq_tick;
474 	}
475 
476 	info->dev = &pdev->dev;
477 	info->data = s3c_rtc_get_data(pdev);
478 	if (!info->data) {
479 		dev_err(&pdev->dev, "failed getting s3c_rtc_data\n");
480 		return -EINVAL;
481 	}
482 	spin_lock_init(&info->pie_lock);
483 	spin_lock_init(&info->alarm_clk_lock);
484 
485 	platform_set_drvdata(pdev, info);
486 
487 	info->irq_alarm = platform_get_irq(pdev, 0);
488 	if (info->irq_alarm < 0) {
489 		dev_err(&pdev->dev, "no irq for alarm\n");
490 		return info->irq_alarm;
491 	}
492 
493 	dev_dbg(&pdev->dev, "s3c2410_rtc: tick irq %d, alarm irq %d\n",
494 		 info->irq_tick, info->irq_alarm);
495 
496 	/* get the memory region */
497 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
498 	info->base = devm_ioremap_resource(&pdev->dev, res);
499 	if (IS_ERR(info->base))
500 		return PTR_ERR(info->base);
501 
502 	info->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
503 	if (IS_ERR(info->rtc_clk)) {
504 		dev_err(&pdev->dev, "failed to find rtc clock\n");
505 		return PTR_ERR(info->rtc_clk);
506 	}
507 	clk_prepare_enable(info->rtc_clk);
508 
509 	if (info->data->needs_src_clk) {
510 		info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
511 		if (IS_ERR(info->rtc_src_clk)) {
512 			dev_err(&pdev->dev,
513 				"failed to find rtc source clock\n");
514 			clk_disable_unprepare(info->rtc_clk);
515 			return PTR_ERR(info->rtc_src_clk);
516 		}
517 		clk_prepare_enable(info->rtc_src_clk);
518 	}
519 
520 	/* check to see if everything is setup correctly */
521 	if (info->data->enable)
522 		info->data->enable(info);
523 
524 	dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n",
525 		 readw(info->base + S3C2410_RTCCON));
526 
527 	device_init_wakeup(&pdev->dev, 1);
528 
529 	/* Check RTC Time */
530 	if (s3c_rtc_gettime(&pdev->dev, &rtc_tm)) {
531 		rtc_tm.tm_year	= 100;
532 		rtc_tm.tm_mon	= 0;
533 		rtc_tm.tm_mday	= 1;
534 		rtc_tm.tm_hour	= 0;
535 		rtc_tm.tm_min	= 0;
536 		rtc_tm.tm_sec	= 0;
537 
538 		s3c_rtc_settime(&pdev->dev, &rtc_tm);
539 
540 		dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
541 	}
542 
543 	/* register RTC and exit */
544 	info->rtc = devm_rtc_device_register(&pdev->dev, "s3c", &s3c_rtcops,
545 				  THIS_MODULE);
546 	if (IS_ERR(info->rtc)) {
547 		dev_err(&pdev->dev, "cannot attach rtc\n");
548 		ret = PTR_ERR(info->rtc);
549 		goto err_nortc;
550 	}
551 
552 	ret = devm_request_irq(&pdev->dev, info->irq_alarm, s3c_rtc_alarmirq,
553 			  0,  "s3c2410-rtc alarm", info);
554 	if (ret) {
555 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_alarm, ret);
556 		goto err_nortc;
557 	}
558 
559 	ret = devm_request_irq(&pdev->dev, info->irq_tick, s3c_rtc_tickirq,
560 			  0,  "s3c2410-rtc tick", info);
561 	if (ret) {
562 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_tick, ret);
563 		goto err_nortc;
564 	}
565 
566 	if (info->data->select_tick_clk)
567 		info->data->select_tick_clk(info);
568 
569 	s3c_rtc_setfreq(info, 1);
570 
571 	s3c_rtc_disable_clk(info);
572 
573 	return 0;
574 
575  err_nortc:
576 	if (info->data->disable)
577 		info->data->disable(info);
578 
579 	if (info->data->needs_src_clk)
580 		clk_disable_unprepare(info->rtc_src_clk);
581 	clk_disable_unprepare(info->rtc_clk);
582 
583 	return ret;
584 }
585 
586 #ifdef CONFIG_PM_SLEEP
587 
588 static int s3c_rtc_suspend(struct device *dev)
589 {
590 	struct s3c_rtc *info = dev_get_drvdata(dev);
591 
592 	s3c_rtc_enable_clk(info);
593 
594 	/* save TICNT for anyone using periodic interrupts */
595 	if (info->data->save_tick_cnt)
596 		info->data->save_tick_cnt(info);
597 
598 	if (info->data->disable)
599 		info->data->disable(info);
600 
601 	if (device_may_wakeup(dev) && !info->wake_en) {
602 		if (enable_irq_wake(info->irq_alarm) == 0)
603 			info->wake_en = true;
604 		else
605 			dev_err(dev, "enable_irq_wake failed\n");
606 	}
607 
608 	return 0;
609 }
610 
611 static int s3c_rtc_resume(struct device *dev)
612 {
613 	struct s3c_rtc *info = dev_get_drvdata(dev);
614 
615 	if (info->data->enable)
616 		info->data->enable(info);
617 
618 	if (info->data->restore_tick_cnt)
619 		info->data->restore_tick_cnt(info);
620 
621 	s3c_rtc_disable_clk(info);
622 
623 	if (device_may_wakeup(dev) && info->wake_en) {
624 		disable_irq_wake(info->irq_alarm);
625 		info->wake_en = false;
626 	}
627 
628 	return 0;
629 }
630 #endif
631 static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume);
632 
633 static void s3c24xx_rtc_irq(struct s3c_rtc *info, int mask)
634 {
635 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
636 }
637 
638 static void s3c6410_rtc_irq(struct s3c_rtc *info, int mask)
639 {
640 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
641 	writeb(mask, info->base + S3C2410_INTP);
642 }
643 
644 static void s3c2410_rtc_setfreq(struct s3c_rtc *info, int freq)
645 {
646 	unsigned int tmp = 0;
647 	int val;
648 
649 	tmp = readb(info->base + S3C2410_TICNT);
650 	tmp &= S3C2410_TICNT_ENABLE;
651 
652 	val = (info->rtc->max_user_freq / freq) - 1;
653 	tmp |= val;
654 
655 	writel(tmp, info->base + S3C2410_TICNT);
656 }
657 
658 static void s3c2416_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(S3C2416_TICNT2_PART(val), info->base + S3C2416_TICNT2);
672 
673 	writel(tmp, info->base + S3C2410_TICNT);
674 }
675 
676 static void s3c2443_rtc_setfreq(struct s3c_rtc *info, int freq)
677 {
678 	unsigned int tmp = 0;
679 	int val;
680 
681 	tmp = readb(info->base + S3C2410_TICNT);
682 	tmp &= S3C2410_TICNT_ENABLE;
683 
684 	val = (info->rtc->max_user_freq / freq) - 1;
685 
686 	tmp |= S3C2443_TICNT_PART(val);
687 	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
688 
689 	writel(tmp, info->base + S3C2410_TICNT);
690 }
691 
692 static void s3c6410_rtc_setfreq(struct s3c_rtc *info, int freq)
693 {
694 	int val;
695 
696 	val = (info->rtc->max_user_freq / freq) - 1;
697 	writel(val, info->base + S3C2410_TICNT);
698 }
699 
700 static void s3c24xx_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
701 {
702 	unsigned int ticnt;
703 
704 	ticnt = readb(info->base + S3C2410_TICNT);
705 	ticnt &= S3C2410_TICNT_ENABLE;
706 
707 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
708 }
709 
710 static void s3c2416_rtc_select_tick_clk(struct s3c_rtc *info)
711 {
712 	unsigned int con;
713 
714 	con = readw(info->base + S3C2410_RTCCON);
715 	con |= S3C2443_RTCCON_TICSEL;
716 	writew(con, info->base + S3C2410_RTCCON);
717 }
718 
719 static void s3c6410_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
720 {
721 	unsigned int ticnt;
722 
723 	ticnt = readw(info->base + S3C2410_RTCCON);
724 	ticnt &= S3C64XX_RTCCON_TICEN;
725 
726 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
727 }
728 
729 static void s3c24xx_rtc_save_tick_cnt(struct s3c_rtc *info)
730 {
731 	info->ticnt_save = readb(info->base + S3C2410_TICNT);
732 }
733 
734 static void s3c24xx_rtc_restore_tick_cnt(struct s3c_rtc *info)
735 {
736 	writeb(info->ticnt_save, info->base + S3C2410_TICNT);
737 }
738 
739 static void s3c6410_rtc_save_tick_cnt(struct s3c_rtc *info)
740 {
741 	info->ticnt_en_save = readw(info->base + S3C2410_RTCCON);
742 	info->ticnt_en_save &= S3C64XX_RTCCON_TICEN;
743 	info->ticnt_save = readl(info->base + S3C2410_TICNT);
744 }
745 
746 static void s3c6410_rtc_restore_tick_cnt(struct s3c_rtc *info)
747 {
748 	unsigned int con;
749 
750 	writel(info->ticnt_save, info->base + S3C2410_TICNT);
751 	if (info->ticnt_en_save) {
752 		con = readw(info->base + S3C2410_RTCCON);
753 		writew(con | info->ticnt_en_save,
754 				info->base + S3C2410_RTCCON);
755 	}
756 }
757 
758 static struct s3c_rtc_data const s3c2410_rtc_data = {
759 	.max_user_freq		= 128,
760 	.irq_handler		= s3c24xx_rtc_irq,
761 	.set_freq		= s3c2410_rtc_setfreq,
762 	.enable_tick		= s3c24xx_rtc_enable_tick,
763 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
764 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
765 	.enable			= s3c24xx_rtc_enable,
766 	.disable		= s3c24xx_rtc_disable,
767 };
768 
769 static struct s3c_rtc_data const s3c2416_rtc_data = {
770 	.max_user_freq		= 32768,
771 	.irq_handler		= s3c24xx_rtc_irq,
772 	.set_freq		= s3c2416_rtc_setfreq,
773 	.enable_tick		= s3c24xx_rtc_enable_tick,
774 	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
775 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
776 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
777 	.enable			= s3c24xx_rtc_enable,
778 	.disable		= s3c24xx_rtc_disable,
779 };
780 
781 static struct s3c_rtc_data const s3c2443_rtc_data = {
782 	.max_user_freq		= 32768,
783 	.irq_handler		= s3c24xx_rtc_irq,
784 	.set_freq		= s3c2443_rtc_setfreq,
785 	.enable_tick		= s3c24xx_rtc_enable_tick,
786 	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
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 s3c6410_rtc_data = {
794 	.max_user_freq		= 32768,
795 	.needs_src_clk		= true,
796 	.irq_handler		= s3c6410_rtc_irq,
797 	.set_freq		= s3c6410_rtc_setfreq,
798 	.enable_tick		= s3c6410_rtc_enable_tick,
799 	.save_tick_cnt		= s3c6410_rtc_save_tick_cnt,
800 	.restore_tick_cnt	= s3c6410_rtc_restore_tick_cnt,
801 	.enable			= s3c24xx_rtc_enable,
802 	.disable		= s3c6410_rtc_disable,
803 };
804 
805 static const struct of_device_id s3c_rtc_dt_match[] = {
806 	{
807 		.compatible = "samsung,s3c2410-rtc",
808 		.data = (void *)&s3c2410_rtc_data,
809 	}, {
810 		.compatible = "samsung,s3c2416-rtc",
811 		.data = (void *)&s3c2416_rtc_data,
812 	}, {
813 		.compatible = "samsung,s3c2443-rtc",
814 		.data = (void *)&s3c2443_rtc_data,
815 	}, {
816 		.compatible = "samsung,s3c6410-rtc",
817 		.data = (void *)&s3c6410_rtc_data,
818 	}, {
819 		.compatible = "samsung,exynos3250-rtc",
820 		.data = (void *)&s3c6410_rtc_data,
821 	},
822 	{ /* sentinel */ },
823 };
824 MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
825 
826 static struct platform_driver s3c_rtc_driver = {
827 	.probe		= s3c_rtc_probe,
828 	.remove		= s3c_rtc_remove,
829 	.driver		= {
830 		.name	= "s3c-rtc",
831 		.pm	= &s3c_rtc_pm_ops,
832 		.of_match_table	= of_match_ptr(s3c_rtc_dt_match),
833 	},
834 };
835 module_platform_driver(s3c_rtc_driver);
836 
837 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
838 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
839 MODULE_LICENSE("GPL");
840 MODULE_ALIAS("platform:s3c2410-rtc");
841