xref: /openbmc/linux/drivers/rtc/rtc-s3c.c (revision a2cce7a9)
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 
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 
342 static 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 
356 static 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 
365 static 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 
396 static 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 
409 static 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 
419 static 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 	if (info->data->needs_src_clk)
426 		clk_unprepare(info->rtc_src_clk);
427 	clk_unprepare(info->rtc_clk);
428 
429 	return 0;
430 }
431 
432 static const struct of_device_id s3c_rtc_dt_match[];
433 
434 static struct s3c_rtc_data *s3c_rtc_get_data(struct platform_device *pdev)
435 {
436 	const struct of_device_id *match;
437 
438 	match = of_match_node(s3c_rtc_dt_match, pdev->dev.of_node);
439 	return (struct s3c_rtc_data *)match->data;
440 }
441 
442 static int s3c_rtc_probe(struct platform_device *pdev)
443 {
444 	struct s3c_rtc *info = NULL;
445 	struct rtc_time rtc_tm;
446 	struct resource *res;
447 	int ret;
448 
449 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
450 	if (!info)
451 		return -ENOMEM;
452 
453 	/* find the IRQs */
454 	info->irq_tick = platform_get_irq(pdev, 1);
455 	if (info->irq_tick < 0) {
456 		dev_err(&pdev->dev, "no irq for rtc tick\n");
457 		return info->irq_tick;
458 	}
459 
460 	info->dev = &pdev->dev;
461 	info->data = s3c_rtc_get_data(pdev);
462 	if (!info->data) {
463 		dev_err(&pdev->dev, "failed getting s3c_rtc_data\n");
464 		return -EINVAL;
465 	}
466 	spin_lock_init(&info->pie_lock);
467 	spin_lock_init(&info->alarm_clk_lock);
468 
469 	platform_set_drvdata(pdev, info);
470 
471 	info->irq_alarm = platform_get_irq(pdev, 0);
472 	if (info->irq_alarm < 0) {
473 		dev_err(&pdev->dev, "no irq for alarm\n");
474 		return info->irq_alarm;
475 	}
476 
477 	dev_dbg(&pdev->dev, "s3c2410_rtc: tick irq %d, alarm irq %d\n",
478 		 info->irq_tick, info->irq_alarm);
479 
480 	/* get the memory region */
481 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
482 	info->base = devm_ioremap_resource(&pdev->dev, res);
483 	if (IS_ERR(info->base))
484 		return PTR_ERR(info->base);
485 
486 	info->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
487 	if (IS_ERR(info->rtc_clk)) {
488 		dev_err(&pdev->dev, "failed to find rtc clock\n");
489 		return PTR_ERR(info->rtc_clk);
490 	}
491 	clk_prepare_enable(info->rtc_clk);
492 
493 	if (info->data->needs_src_clk) {
494 		info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
495 		if (IS_ERR(info->rtc_src_clk)) {
496 			dev_err(&pdev->dev,
497 				"failed to find rtc source clock\n");
498 			clk_disable_unprepare(info->rtc_clk);
499 			return PTR_ERR(info->rtc_src_clk);
500 		}
501 		clk_prepare_enable(info->rtc_src_clk);
502 	}
503 
504 	/* check to see if everything is setup correctly */
505 	if (info->data->enable)
506 		info->data->enable(info);
507 
508 	dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n",
509 		 readw(info->base + S3C2410_RTCCON));
510 
511 	device_init_wakeup(&pdev->dev, 1);
512 
513 	/* Check RTC Time */
514 	if (s3c_rtc_gettime(&pdev->dev, &rtc_tm)) {
515 		rtc_tm.tm_year	= 100;
516 		rtc_tm.tm_mon	= 0;
517 		rtc_tm.tm_mday	= 1;
518 		rtc_tm.tm_hour	= 0;
519 		rtc_tm.tm_min	= 0;
520 		rtc_tm.tm_sec	= 0;
521 
522 		s3c_rtc_settime(&pdev->dev, &rtc_tm);
523 
524 		dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
525 	}
526 
527 	/* register RTC and exit */
528 	info->rtc = devm_rtc_device_register(&pdev->dev, "s3c", &s3c_rtcops,
529 				  THIS_MODULE);
530 	if (IS_ERR(info->rtc)) {
531 		dev_err(&pdev->dev, "cannot attach rtc\n");
532 		ret = PTR_ERR(info->rtc);
533 		goto err_nortc;
534 	}
535 
536 	ret = devm_request_irq(&pdev->dev, info->irq_alarm, s3c_rtc_alarmirq,
537 			  0,  "s3c2410-rtc alarm", info);
538 	if (ret) {
539 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_alarm, ret);
540 		goto err_nortc;
541 	}
542 
543 	ret = devm_request_irq(&pdev->dev, info->irq_tick, s3c_rtc_tickirq,
544 			  0,  "s3c2410-rtc tick", info);
545 	if (ret) {
546 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_tick, ret);
547 		goto err_nortc;
548 	}
549 
550 	if (info->data->select_tick_clk)
551 		info->data->select_tick_clk(info);
552 
553 	s3c_rtc_setfreq(info, 1);
554 
555 	s3c_rtc_disable_clk(info);
556 
557 	return 0;
558 
559  err_nortc:
560 	if (info->data->disable)
561 		info->data->disable(info);
562 
563 	if (info->data->needs_src_clk)
564 		clk_disable_unprepare(info->rtc_src_clk);
565 	clk_disable_unprepare(info->rtc_clk);
566 
567 	return ret;
568 }
569 
570 #ifdef CONFIG_PM_SLEEP
571 
572 static int s3c_rtc_suspend(struct device *dev)
573 {
574 	struct s3c_rtc *info = dev_get_drvdata(dev);
575 
576 	s3c_rtc_enable_clk(info);
577 
578 	/* save TICNT for anyone using periodic interrupts */
579 	if (info->data->save_tick_cnt)
580 		info->data->save_tick_cnt(info);
581 
582 	if (info->data->disable)
583 		info->data->disable(info);
584 
585 	if (device_may_wakeup(dev) && !info->wake_en) {
586 		if (enable_irq_wake(info->irq_alarm) == 0)
587 			info->wake_en = true;
588 		else
589 			dev_err(dev, "enable_irq_wake failed\n");
590 	}
591 
592 	return 0;
593 }
594 
595 static int s3c_rtc_resume(struct device *dev)
596 {
597 	struct s3c_rtc *info = dev_get_drvdata(dev);
598 
599 	if (info->data->enable)
600 		info->data->enable(info);
601 
602 	if (info->data->restore_tick_cnt)
603 		info->data->restore_tick_cnt(info);
604 
605 	s3c_rtc_disable_clk(info);
606 
607 	if (device_may_wakeup(dev) && info->wake_en) {
608 		disable_irq_wake(info->irq_alarm);
609 		info->wake_en = false;
610 	}
611 
612 	return 0;
613 }
614 #endif
615 static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume);
616 
617 static void s3c24xx_rtc_irq(struct s3c_rtc *info, int mask)
618 {
619 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
620 }
621 
622 static void s3c6410_rtc_irq(struct s3c_rtc *info, int mask)
623 {
624 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
625 	writeb(mask, info->base + S3C2410_INTP);
626 }
627 
628 static void s3c2410_rtc_setfreq(struct s3c_rtc *info, int freq)
629 {
630 	unsigned int tmp = 0;
631 	int val;
632 
633 	tmp = readb(info->base + S3C2410_TICNT);
634 	tmp &= S3C2410_TICNT_ENABLE;
635 
636 	val = (info->rtc->max_user_freq / freq) - 1;
637 	tmp |= val;
638 
639 	writel(tmp, info->base + S3C2410_TICNT);
640 }
641 
642 static void s3c2416_rtc_setfreq(struct s3c_rtc *info, int freq)
643 {
644 	unsigned int tmp = 0;
645 	int val;
646 
647 	tmp = readb(info->base + S3C2410_TICNT);
648 	tmp &= S3C2410_TICNT_ENABLE;
649 
650 	val = (info->rtc->max_user_freq / freq) - 1;
651 
652 	tmp |= S3C2443_TICNT_PART(val);
653 	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
654 
655 	writel(S3C2416_TICNT2_PART(val), info->base + S3C2416_TICNT2);
656 
657 	writel(tmp, info->base + S3C2410_TICNT);
658 }
659 
660 static void s3c2443_rtc_setfreq(struct s3c_rtc *info, int freq)
661 {
662 	unsigned int tmp = 0;
663 	int val;
664 
665 	tmp = readb(info->base + S3C2410_TICNT);
666 	tmp &= S3C2410_TICNT_ENABLE;
667 
668 	val = (info->rtc->max_user_freq / freq) - 1;
669 
670 	tmp |= S3C2443_TICNT_PART(val);
671 	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
672 
673 	writel(tmp, info->base + S3C2410_TICNT);
674 }
675 
676 static void s3c6410_rtc_setfreq(struct s3c_rtc *info, int freq)
677 {
678 	int val;
679 
680 	val = (info->rtc->max_user_freq / freq) - 1;
681 	writel(val, info->base + S3C2410_TICNT);
682 }
683 
684 static void s3c24xx_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
685 {
686 	unsigned int ticnt;
687 
688 	ticnt = readb(info->base + S3C2410_TICNT);
689 	ticnt &= S3C2410_TICNT_ENABLE;
690 
691 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
692 }
693 
694 static void s3c2416_rtc_select_tick_clk(struct s3c_rtc *info)
695 {
696 	unsigned int con;
697 
698 	con = readw(info->base + S3C2410_RTCCON);
699 	con |= S3C2443_RTCCON_TICSEL;
700 	writew(con, info->base + S3C2410_RTCCON);
701 }
702 
703 static void s3c6410_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
704 {
705 	unsigned int ticnt;
706 
707 	ticnt = readw(info->base + S3C2410_RTCCON);
708 	ticnt &= S3C64XX_RTCCON_TICEN;
709 
710 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
711 }
712 
713 static void s3c24xx_rtc_save_tick_cnt(struct s3c_rtc *info)
714 {
715 	info->ticnt_save = readb(info->base + S3C2410_TICNT);
716 }
717 
718 static void s3c24xx_rtc_restore_tick_cnt(struct s3c_rtc *info)
719 {
720 	writeb(info->ticnt_save, info->base + S3C2410_TICNT);
721 }
722 
723 static void s3c6410_rtc_save_tick_cnt(struct s3c_rtc *info)
724 {
725 	info->ticnt_en_save = readw(info->base + S3C2410_RTCCON);
726 	info->ticnt_en_save &= S3C64XX_RTCCON_TICEN;
727 	info->ticnt_save = readl(info->base + S3C2410_TICNT);
728 }
729 
730 static void s3c6410_rtc_restore_tick_cnt(struct s3c_rtc *info)
731 {
732 	unsigned int con;
733 
734 	writel(info->ticnt_save, info->base + S3C2410_TICNT);
735 	if (info->ticnt_en_save) {
736 		con = readw(info->base + S3C2410_RTCCON);
737 		writew(con | info->ticnt_en_save,
738 				info->base + S3C2410_RTCCON);
739 	}
740 }
741 
742 static struct s3c_rtc_data const s3c2410_rtc_data = {
743 	.max_user_freq		= 128,
744 	.irq_handler		= s3c24xx_rtc_irq,
745 	.set_freq		= s3c2410_rtc_setfreq,
746 	.enable_tick		= s3c24xx_rtc_enable_tick,
747 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
748 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
749 	.enable			= s3c24xx_rtc_enable,
750 	.disable		= s3c24xx_rtc_disable,
751 };
752 
753 static struct s3c_rtc_data const s3c2416_rtc_data = {
754 	.max_user_freq		= 32768,
755 	.irq_handler		= s3c24xx_rtc_irq,
756 	.set_freq		= s3c2416_rtc_setfreq,
757 	.enable_tick		= s3c24xx_rtc_enable_tick,
758 	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
759 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
760 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
761 	.enable			= s3c24xx_rtc_enable,
762 	.disable		= s3c24xx_rtc_disable,
763 };
764 
765 static struct s3c_rtc_data const s3c2443_rtc_data = {
766 	.max_user_freq		= 32768,
767 	.irq_handler		= s3c24xx_rtc_irq,
768 	.set_freq		= s3c2443_rtc_setfreq,
769 	.enable_tick		= s3c24xx_rtc_enable_tick,
770 	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
771 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
772 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
773 	.enable			= s3c24xx_rtc_enable,
774 	.disable		= s3c24xx_rtc_disable,
775 };
776 
777 static struct s3c_rtc_data const s3c6410_rtc_data = {
778 	.max_user_freq		= 32768,
779 	.needs_src_clk		= true,
780 	.irq_handler		= s3c6410_rtc_irq,
781 	.set_freq		= s3c6410_rtc_setfreq,
782 	.enable_tick		= s3c6410_rtc_enable_tick,
783 	.save_tick_cnt		= s3c6410_rtc_save_tick_cnt,
784 	.restore_tick_cnt	= s3c6410_rtc_restore_tick_cnt,
785 	.enable			= s3c24xx_rtc_enable,
786 	.disable		= s3c6410_rtc_disable,
787 };
788 
789 static const struct of_device_id s3c_rtc_dt_match[] = {
790 	{
791 		.compatible = "samsung,s3c2410-rtc",
792 		.data = (void *)&s3c2410_rtc_data,
793 	}, {
794 		.compatible = "samsung,s3c2416-rtc",
795 		.data = (void *)&s3c2416_rtc_data,
796 	}, {
797 		.compatible = "samsung,s3c2443-rtc",
798 		.data = (void *)&s3c2443_rtc_data,
799 	}, {
800 		.compatible = "samsung,s3c6410-rtc",
801 		.data = (void *)&s3c6410_rtc_data,
802 	}, {
803 		.compatible = "samsung,exynos3250-rtc",
804 		.data = (void *)&s3c6410_rtc_data,
805 	},
806 	{ /* sentinel */ },
807 };
808 MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
809 
810 static struct platform_driver s3c_rtc_driver = {
811 	.probe		= s3c_rtc_probe,
812 	.remove		= s3c_rtc_remove,
813 	.driver		= {
814 		.name	= "s3c-rtc",
815 		.pm	= &s3c_rtc_pm_ops,
816 		.of_match_table	= of_match_ptr(s3c_rtc_dt_match),
817 	},
818 };
819 module_platform_driver(s3c_rtc_driver);
820 
821 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
822 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
823 MODULE_LICENSE("GPL");
824 MODULE_ALIAS("platform:s3c2410-rtc");
825