xref: /openbmc/linux/drivers/rtc/rtc-s3c.c (revision b830f94f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* drivers/rtc/rtc-s3c.c
3  *
4  * Copyright (c) 2010 Samsung Electronics Co., Ltd.
5  *		http://www.samsung.com/
6  *
7  * Copyright (c) 2004,2006 Simtec Electronics
8  *	Ben Dooks, <ben@simtec.co.uk>
9  *	http://armlinux.simtec.co.uk/
10  *
11  * S3C2410/S3C2440/S3C24XX Internal RTC Driver
12 */
13 
14 #include <linux/module.h>
15 #include <linux/fs.h>
16 #include <linux/string.h>
17 #include <linux/init.h>
18 #include <linux/platform_device.h>
19 #include <linux/interrupt.h>
20 #include <linux/rtc.h>
21 #include <linux/bcd.h>
22 #include <linux/clk.h>
23 #include <linux/log2.h>
24 #include <linux/slab.h>
25 #include <linux/of.h>
26 #include <linux/of_device.h>
27 #include <linux/uaccess.h>
28 #include <linux/io.h>
29 
30 #include <asm/irq.h>
31 #include "rtc-s3c.h"
32 
33 struct s3c_rtc {
34 	struct device *dev;
35 	struct rtc_device *rtc;
36 
37 	void __iomem *base;
38 	struct clk *rtc_clk;
39 	struct clk *rtc_src_clk;
40 	bool alarm_enabled;
41 
42 	const struct s3c_rtc_data *data;
43 
44 	int irq_alarm;
45 	int irq_tick;
46 
47 	spinlock_t pie_lock;
48 	spinlock_t alarm_lock;
49 
50 	int ticnt_save;
51 	int ticnt_en_save;
52 	bool wake_en;
53 };
54 
55 struct s3c_rtc_data {
56 	int max_user_freq;
57 	bool needs_src_clk;
58 
59 	void (*irq_handler) (struct s3c_rtc *info, int mask);
60 	void (*set_freq) (struct s3c_rtc *info, int freq);
61 	void (*enable_tick) (struct s3c_rtc *info, struct seq_file *seq);
62 	void (*select_tick_clk) (struct s3c_rtc *info);
63 	void (*save_tick_cnt) (struct s3c_rtc *info);
64 	void (*restore_tick_cnt) (struct s3c_rtc *info);
65 	void (*enable) (struct s3c_rtc *info);
66 	void (*disable) (struct s3c_rtc *info);
67 };
68 
69 static int s3c_rtc_enable_clk(struct s3c_rtc *info)
70 {
71 	int ret;
72 
73 	ret = clk_enable(info->rtc_clk);
74 	if (ret)
75 		return ret;
76 
77 	if (info->data->needs_src_clk) {
78 		ret = clk_enable(info->rtc_src_clk);
79 		if (ret) {
80 			clk_disable(info->rtc_clk);
81 			return ret;
82 		}
83 	}
84 	return 0;
85 }
86 
87 static void s3c_rtc_disable_clk(struct s3c_rtc *info)
88 {
89 	if (info->data->needs_src_clk)
90 		clk_disable(info->rtc_src_clk);
91 	clk_disable(info->rtc_clk);
92 }
93 
94 /* IRQ Handlers */
95 static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
96 {
97 	struct s3c_rtc *info = (struct s3c_rtc *)id;
98 
99 	if (info->data->irq_handler)
100 		info->data->irq_handler(info, S3C2410_INTP_TIC);
101 
102 	return IRQ_HANDLED;
103 }
104 
105 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
106 {
107 	struct s3c_rtc *info = (struct s3c_rtc *)id;
108 
109 	if (info->data->irq_handler)
110 		info->data->irq_handler(info, S3C2410_INTP_ALM);
111 
112 	return IRQ_HANDLED;
113 }
114 
115 /* Update control registers */
116 static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
117 {
118 	struct s3c_rtc *info = dev_get_drvdata(dev);
119 	unsigned long flags;
120 	unsigned int tmp;
121 	int ret;
122 
123 	dev_dbg(info->dev, "%s: aie=%d\n", __func__, enabled);
124 
125 	ret = s3c_rtc_enable_clk(info);
126 	if (ret)
127 		return ret;
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 	spin_lock_irqsave(&info->alarm_lock, flags);
137 
138 	if (info->alarm_enabled && !enabled)
139 		s3c_rtc_disable_clk(info);
140 	else if (!info->alarm_enabled && enabled)
141 		ret = s3c_rtc_enable_clk(info);
142 
143 	info->alarm_enabled = enabled;
144 	spin_unlock_irqrestore(&info->alarm_lock, flags);
145 
146 	s3c_rtc_disable_clk(info);
147 
148 	return ret;
149 }
150 
151 /* Set RTC frequency */
152 static int s3c_rtc_setfreq(struct s3c_rtc *info, int freq)
153 {
154 	int ret;
155 
156 	if (!is_power_of_2(freq))
157 		return -EINVAL;
158 
159 	ret = s3c_rtc_enable_clk(info);
160 	if (ret)
161 		return ret;
162 	spin_lock_irq(&info->pie_lock);
163 
164 	if (info->data->set_freq)
165 		info->data->set_freq(info, freq);
166 
167 	spin_unlock_irq(&info->pie_lock);
168 	s3c_rtc_disable_clk(info);
169 
170 	return 0;
171 }
172 
173 /* Time read/write */
174 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
175 {
176 	struct s3c_rtc *info = dev_get_drvdata(dev);
177 	unsigned int have_retried = 0;
178 	int ret;
179 
180 	ret = s3c_rtc_enable_clk(info);
181 	if (ret)
182 		return ret;
183 
184 retry_get_time:
185 	rtc_tm->tm_min  = readb(info->base + S3C2410_RTCMIN);
186 	rtc_tm->tm_hour = readb(info->base + S3C2410_RTCHOUR);
187 	rtc_tm->tm_mday = readb(info->base + S3C2410_RTCDATE);
188 	rtc_tm->tm_mon  = readb(info->base + S3C2410_RTCMON);
189 	rtc_tm->tm_year = readb(info->base + S3C2410_RTCYEAR);
190 	rtc_tm->tm_sec  = readb(info->base + S3C2410_RTCSEC);
191 
192 	/* the only way to work out whether the system was mid-update
193 	 * when we read it is to check the second counter, and if it
194 	 * is zero, then we re-try the entire read
195 	 */
196 
197 	if (rtc_tm->tm_sec == 0 && !have_retried) {
198 		have_retried = 1;
199 		goto retry_get_time;
200 	}
201 
202 	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
203 	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
204 	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
205 	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
206 	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
207 	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
208 
209 	s3c_rtc_disable_clk(info);
210 
211 	rtc_tm->tm_year += 100;
212 	rtc_tm->tm_mon -= 1;
213 
214 	dev_dbg(dev, "read time %ptR\n", rtc_tm);
215 	return 0;
216 }
217 
218 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
219 {
220 	struct s3c_rtc *info = dev_get_drvdata(dev);
221 	int year = tm->tm_year - 100;
222 	int ret;
223 
224 	dev_dbg(dev, "set time %ptR\n", tm);
225 
226 	/* we get around y2k by simply not supporting it */
227 
228 	if (year < 0 || year >= 100) {
229 		dev_err(dev, "rtc only supports 100 years\n");
230 		return -EINVAL;
231 	}
232 
233 	ret = s3c_rtc_enable_clk(info);
234 	if (ret)
235 		return ret;
236 
237 	writeb(bin2bcd(tm->tm_sec),  info->base + S3C2410_RTCSEC);
238 	writeb(bin2bcd(tm->tm_min),  info->base + S3C2410_RTCMIN);
239 	writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_RTCHOUR);
240 	writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_RTCDATE);
241 	writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_RTCMON);
242 	writeb(bin2bcd(year), info->base + S3C2410_RTCYEAR);
243 
244 	s3c_rtc_disable_clk(info);
245 
246 	return 0;
247 }
248 
249 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
250 {
251 	struct s3c_rtc *info = dev_get_drvdata(dev);
252 	struct rtc_time *alm_tm = &alrm->time;
253 	unsigned int alm_en;
254 	int ret;
255 
256 	ret = s3c_rtc_enable_clk(info);
257 	if (ret)
258 		return ret;
259 
260 	alm_tm->tm_sec  = readb(info->base + S3C2410_ALMSEC);
261 	alm_tm->tm_min  = readb(info->base + S3C2410_ALMMIN);
262 	alm_tm->tm_hour = readb(info->base + S3C2410_ALMHOUR);
263 	alm_tm->tm_mon  = readb(info->base + S3C2410_ALMMON);
264 	alm_tm->tm_mday = readb(info->base + S3C2410_ALMDATE);
265 	alm_tm->tm_year = readb(info->base + S3C2410_ALMYEAR);
266 
267 	alm_en = readb(info->base + S3C2410_RTCALM);
268 
269 	s3c_rtc_disable_clk(info);
270 
271 	alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
272 
273 	dev_dbg(dev, "read alarm %d, %ptR\n", alm_en, alm_tm);
274 
275 	/* decode the alarm enable field */
276 	if (alm_en & S3C2410_RTCALM_SECEN)
277 		alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
278 
279 	if (alm_en & S3C2410_RTCALM_MINEN)
280 		alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
281 
282 	if (alm_en & S3C2410_RTCALM_HOUREN)
283 		alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
284 
285 	if (alm_en & S3C2410_RTCALM_DAYEN)
286 		alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
287 
288 	if (alm_en & S3C2410_RTCALM_MONEN) {
289 		alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
290 		alm_tm->tm_mon -= 1;
291 	}
292 
293 	if (alm_en & S3C2410_RTCALM_YEAREN)
294 		alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
295 
296 	return 0;
297 }
298 
299 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
300 {
301 	struct s3c_rtc *info = dev_get_drvdata(dev);
302 	struct rtc_time *tm = &alrm->time;
303 	unsigned int alrm_en;
304 	int ret;
305 
306 	dev_dbg(dev, "s3c_rtc_setalarm: %d, %ptR\n", alrm->enabled, tm);
307 
308 	ret = s3c_rtc_enable_clk(info);
309 	if (ret)
310 		return ret;
311 
312 	alrm_en = readb(info->base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
313 	writeb(0x00, info->base + S3C2410_RTCALM);
314 
315 	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
316 		alrm_en |= S3C2410_RTCALM_SECEN;
317 		writeb(bin2bcd(tm->tm_sec), info->base + S3C2410_ALMSEC);
318 	}
319 
320 	if (tm->tm_min < 60 && tm->tm_min >= 0) {
321 		alrm_en |= S3C2410_RTCALM_MINEN;
322 		writeb(bin2bcd(tm->tm_min), info->base + S3C2410_ALMMIN);
323 	}
324 
325 	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
326 		alrm_en |= S3C2410_RTCALM_HOUREN;
327 		writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_ALMHOUR);
328 	}
329 
330 	if (tm->tm_mon < 12 && tm->tm_mon >= 0) {
331 		alrm_en |= S3C2410_RTCALM_MONEN;
332 		writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_ALMMON);
333 	}
334 
335 	if (tm->tm_mday <= 31 && tm->tm_mday >= 1) {
336 		alrm_en |= S3C2410_RTCALM_DAYEN;
337 		writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_ALMDATE);
338 	}
339 
340 	dev_dbg(dev, "setting S3C2410_RTCALM to %08x\n", alrm_en);
341 
342 	writeb(alrm_en, info->base + S3C2410_RTCALM);
343 
344 	s3c_rtc_setaie(dev, alrm->enabled);
345 
346 	s3c_rtc_disable_clk(info);
347 
348 	return 0;
349 }
350 
351 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
352 {
353 	struct s3c_rtc *info = dev_get_drvdata(dev);
354 	int ret;
355 
356 	ret = s3c_rtc_enable_clk(info);
357 	if (ret)
358 		return ret;
359 
360 	if (info->data->enable_tick)
361 		info->data->enable_tick(info, seq);
362 
363 	s3c_rtc_disable_clk(info);
364 
365 	return 0;
366 }
367 
368 static const struct rtc_class_ops s3c_rtcops = {
369 	.read_time	= s3c_rtc_gettime,
370 	.set_time	= s3c_rtc_settime,
371 	.read_alarm	= s3c_rtc_getalarm,
372 	.set_alarm	= s3c_rtc_setalarm,
373 	.proc		= s3c_rtc_proc,
374 	.alarm_irq_enable = s3c_rtc_setaie,
375 };
376 
377 static void s3c24xx_rtc_enable(struct s3c_rtc *info)
378 {
379 	unsigned int con, tmp;
380 
381 	con = readw(info->base + S3C2410_RTCCON);
382 	/* re-enable the device, and check it is ok */
383 	if ((con & S3C2410_RTCCON_RTCEN) == 0) {
384 		dev_info(info->dev, "rtc disabled, re-enabling\n");
385 
386 		tmp = readw(info->base + S3C2410_RTCCON);
387 		writew(tmp | S3C2410_RTCCON_RTCEN, info->base + S3C2410_RTCCON);
388 	}
389 
390 	if (con & S3C2410_RTCCON_CNTSEL) {
391 		dev_info(info->dev, "removing RTCCON_CNTSEL\n");
392 
393 		tmp = readw(info->base + S3C2410_RTCCON);
394 		writew(tmp & ~S3C2410_RTCCON_CNTSEL,
395 		       info->base + S3C2410_RTCCON);
396 	}
397 
398 	if (con & S3C2410_RTCCON_CLKRST) {
399 		dev_info(info->dev, "removing RTCCON_CLKRST\n");
400 
401 		tmp = readw(info->base + S3C2410_RTCCON);
402 		writew(tmp & ~S3C2410_RTCCON_CLKRST,
403 		       info->base + S3C2410_RTCCON);
404 	}
405 }
406 
407 static void s3c24xx_rtc_disable(struct s3c_rtc *info)
408 {
409 	unsigned int con;
410 
411 	con = readw(info->base + S3C2410_RTCCON);
412 	con &= ~S3C2410_RTCCON_RTCEN;
413 	writew(con, info->base + S3C2410_RTCCON);
414 
415 	con = readb(info->base + S3C2410_TICNT);
416 	con &= ~S3C2410_TICNT_ENABLE;
417 	writeb(con, info->base + S3C2410_TICNT);
418 }
419 
420 static void s3c6410_rtc_disable(struct s3c_rtc *info)
421 {
422 	unsigned int con;
423 
424 	con = readw(info->base + S3C2410_RTCCON);
425 	con &= ~S3C64XX_RTCCON_TICEN;
426 	con &= ~S3C2410_RTCCON_RTCEN;
427 	writew(con, info->base + S3C2410_RTCCON);
428 }
429 
430 static int s3c_rtc_remove(struct platform_device *pdev)
431 {
432 	struct s3c_rtc *info = platform_get_drvdata(pdev);
433 
434 	s3c_rtc_setaie(info->dev, 0);
435 
436 	if (info->data->needs_src_clk)
437 		clk_unprepare(info->rtc_src_clk);
438 	clk_unprepare(info->rtc_clk);
439 
440 	return 0;
441 }
442 
443 static int s3c_rtc_probe(struct platform_device *pdev)
444 {
445 	struct s3c_rtc *info = NULL;
446 	struct rtc_time rtc_tm;
447 	struct resource *res;
448 	int ret;
449 
450 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
451 	if (!info)
452 		return -ENOMEM;
453 
454 	/* find the IRQs */
455 	info->irq_tick = platform_get_irq(pdev, 1);
456 	if (info->irq_tick < 0) {
457 		dev_err(&pdev->dev, "no irq for rtc tick\n");
458 		return info->irq_tick;
459 	}
460 
461 	info->dev = &pdev->dev;
462 	info->data = of_device_get_match_data(&pdev->dev);
463 	if (!info->data) {
464 		dev_err(&pdev->dev, "failed getting s3c_rtc_data\n");
465 		return -EINVAL;
466 	}
467 	spin_lock_init(&info->pie_lock);
468 	spin_lock_init(&info->alarm_lock);
469 
470 	platform_set_drvdata(pdev, info);
471 
472 	info->irq_alarm = platform_get_irq(pdev, 0);
473 	if (info->irq_alarm < 0) {
474 		dev_err(&pdev->dev, "no irq for alarm\n");
475 		return info->irq_alarm;
476 	}
477 
478 	dev_dbg(&pdev->dev, "s3c2410_rtc: tick irq %d, alarm irq %d\n",
479 		info->irq_tick, info->irq_alarm);
480 
481 	/* get the memory region */
482 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
483 	info->base = devm_ioremap_resource(&pdev->dev, res);
484 	if (IS_ERR(info->base))
485 		return PTR_ERR(info->base);
486 
487 	info->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
488 	if (IS_ERR(info->rtc_clk)) {
489 		ret = PTR_ERR(info->rtc_clk);
490 		if (ret != -EPROBE_DEFER)
491 			dev_err(&pdev->dev, "failed to find rtc clock\n");
492 		else
493 			dev_dbg(&pdev->dev, "probe deferred due to missing rtc clk\n");
494 		return ret;
495 	}
496 	ret = clk_prepare_enable(info->rtc_clk);
497 	if (ret)
498 		return ret;
499 
500 	if (info->data->needs_src_clk) {
501 		info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
502 		if (IS_ERR(info->rtc_src_clk)) {
503 			ret = PTR_ERR(info->rtc_src_clk);
504 			if (ret != -EPROBE_DEFER)
505 				dev_err(&pdev->dev,
506 					"failed to find rtc source clock\n");
507 			else
508 				dev_dbg(&pdev->dev,
509 					"probe deferred due to missing rtc src clk\n");
510 			goto err_src_clk;
511 		}
512 		ret = clk_prepare_enable(info->rtc_src_clk);
513 		if (ret)
514 			goto err_src_clk;
515 	}
516 
517 	/* check to see if everything is setup correctly */
518 	if (info->data->enable)
519 		info->data->enable(info);
520 
521 	dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n",
522 		readw(info->base + S3C2410_RTCCON));
523 
524 	device_init_wakeup(&pdev->dev, 1);
525 
526 	/* Check RTC Time */
527 	if (s3c_rtc_gettime(&pdev->dev, &rtc_tm)) {
528 		rtc_tm.tm_year	= 100;
529 		rtc_tm.tm_mon	= 0;
530 		rtc_tm.tm_mday	= 1;
531 		rtc_tm.tm_hour	= 0;
532 		rtc_tm.tm_min	= 0;
533 		rtc_tm.tm_sec	= 0;
534 
535 		s3c_rtc_settime(&pdev->dev, &rtc_tm);
536 
537 		dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
538 	}
539 
540 	/* register RTC and exit */
541 	info->rtc = devm_rtc_device_register(&pdev->dev, "s3c", &s3c_rtcops,
542 					     THIS_MODULE);
543 	if (IS_ERR(info->rtc)) {
544 		dev_err(&pdev->dev, "cannot attach rtc\n");
545 		ret = PTR_ERR(info->rtc);
546 		goto err_nortc;
547 	}
548 
549 	ret = devm_request_irq(&pdev->dev, info->irq_alarm, s3c_rtc_alarmirq,
550 			       0, "s3c2410-rtc alarm", info);
551 	if (ret) {
552 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_alarm, ret);
553 		goto err_nortc;
554 	}
555 
556 	ret = devm_request_irq(&pdev->dev, info->irq_tick, s3c_rtc_tickirq,
557 			       0, "s3c2410-rtc tick", info);
558 	if (ret) {
559 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_tick, ret);
560 		goto err_nortc;
561 	}
562 
563 	if (info->data->select_tick_clk)
564 		info->data->select_tick_clk(info);
565 
566 	s3c_rtc_setfreq(info, 1);
567 
568 	s3c_rtc_disable_clk(info);
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 err_src_clk:
579 	clk_disable_unprepare(info->rtc_clk);
580 
581 	return ret;
582 }
583 
584 #ifdef CONFIG_PM_SLEEP
585 
586 static int s3c_rtc_suspend(struct device *dev)
587 {
588 	struct s3c_rtc *info = dev_get_drvdata(dev);
589 	int ret;
590 
591 	ret = s3c_rtc_enable_clk(info);
592 	if (ret)
593 		return ret;
594 
595 	/* save TICNT for anyone using periodic interrupts */
596 	if (info->data->save_tick_cnt)
597 		info->data->save_tick_cnt(info);
598 
599 	if (info->data->disable)
600 		info->data->disable(info);
601 
602 	if (device_may_wakeup(dev) && !info->wake_en) {
603 		if (enable_irq_wake(info->irq_alarm) == 0)
604 			info->wake_en = true;
605 		else
606 			dev_err(dev, "enable_irq_wake failed\n");
607 	}
608 
609 	return 0;
610 }
611 
612 static int s3c_rtc_resume(struct device *dev)
613 {
614 	struct s3c_rtc *info = dev_get_drvdata(dev);
615 
616 	if (info->data->enable)
617 		info->data->enable(info);
618 
619 	if (info->data->restore_tick_cnt)
620 		info->data->restore_tick_cnt(info);
621 
622 	s3c_rtc_disable_clk(info);
623 
624 	if (device_may_wakeup(dev) && info->wake_en) {
625 		disable_irq_wake(info->irq_alarm);
626 		info->wake_en = false;
627 	}
628 
629 	return 0;
630 }
631 #endif
632 static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume);
633 
634 static void s3c24xx_rtc_irq(struct s3c_rtc *info, int mask)
635 {
636 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
637 }
638 
639 static void s3c6410_rtc_irq(struct s3c_rtc *info, int mask)
640 {
641 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
642 	writeb(mask, info->base + S3C2410_INTP);
643 }
644 
645 static void s3c2410_rtc_setfreq(struct s3c_rtc *info, int freq)
646 {
647 	unsigned int tmp = 0;
648 	int val;
649 
650 	tmp = readb(info->base + S3C2410_TICNT);
651 	tmp &= S3C2410_TICNT_ENABLE;
652 
653 	val = (info->rtc->max_user_freq / freq) - 1;
654 	tmp |= val;
655 
656 	writel(tmp, info->base + S3C2410_TICNT);
657 }
658 
659 static void s3c2416_rtc_setfreq(struct s3c_rtc *info, int freq)
660 {
661 	unsigned int tmp = 0;
662 	int val;
663 
664 	tmp = readb(info->base + S3C2410_TICNT);
665 	tmp &= S3C2410_TICNT_ENABLE;
666 
667 	val = (info->rtc->max_user_freq / freq) - 1;
668 
669 	tmp |= S3C2443_TICNT_PART(val);
670 	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
671 
672 	writel(S3C2416_TICNT2_PART(val), info->base + S3C2416_TICNT2);
673 
674 	writel(tmp, info->base + S3C2410_TICNT);
675 }
676 
677 static void s3c2443_rtc_setfreq(struct s3c_rtc *info, int freq)
678 {
679 	unsigned int tmp = 0;
680 	int val;
681 
682 	tmp = readb(info->base + S3C2410_TICNT);
683 	tmp &= S3C2410_TICNT_ENABLE;
684 
685 	val = (info->rtc->max_user_freq / freq) - 1;
686 
687 	tmp |= S3C2443_TICNT_PART(val);
688 	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
689 
690 	writel(tmp, info->base + S3C2410_TICNT);
691 }
692 
693 static void s3c6410_rtc_setfreq(struct s3c_rtc *info, int freq)
694 {
695 	int val;
696 
697 	val = (info->rtc->max_user_freq / freq) - 1;
698 	writel(val, info->base + S3C2410_TICNT);
699 }
700 
701 static void s3c24xx_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
702 {
703 	unsigned int ticnt;
704 
705 	ticnt = readb(info->base + S3C2410_TICNT);
706 	ticnt &= S3C2410_TICNT_ENABLE;
707 
708 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
709 }
710 
711 static void s3c2416_rtc_select_tick_clk(struct s3c_rtc *info)
712 {
713 	unsigned int con;
714 
715 	con = readw(info->base + S3C2410_RTCCON);
716 	con |= S3C2443_RTCCON_TICSEL;
717 	writew(con, info->base + S3C2410_RTCCON);
718 }
719 
720 static void s3c6410_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
721 {
722 	unsigned int ticnt;
723 
724 	ticnt = readw(info->base + S3C2410_RTCCON);
725 	ticnt &= S3C64XX_RTCCON_TICEN;
726 
727 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
728 }
729 
730 static void s3c24xx_rtc_save_tick_cnt(struct s3c_rtc *info)
731 {
732 	info->ticnt_save = readb(info->base + S3C2410_TICNT);
733 }
734 
735 static void s3c24xx_rtc_restore_tick_cnt(struct s3c_rtc *info)
736 {
737 	writeb(info->ticnt_save, info->base + S3C2410_TICNT);
738 }
739 
740 static void s3c6410_rtc_save_tick_cnt(struct s3c_rtc *info)
741 {
742 	info->ticnt_en_save = readw(info->base + S3C2410_RTCCON);
743 	info->ticnt_en_save &= S3C64XX_RTCCON_TICEN;
744 	info->ticnt_save = readl(info->base + S3C2410_TICNT);
745 }
746 
747 static void s3c6410_rtc_restore_tick_cnt(struct s3c_rtc *info)
748 {
749 	unsigned int con;
750 
751 	writel(info->ticnt_save, info->base + S3C2410_TICNT);
752 	if (info->ticnt_en_save) {
753 		con = readw(info->base + S3C2410_RTCCON);
754 		writew(con | info->ticnt_en_save, 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 = &s3c2410_rtc_data,
809 	}, {
810 		.compatible = "samsung,s3c2416-rtc",
811 		.data = &s3c2416_rtc_data,
812 	}, {
813 		.compatible = "samsung,s3c2443-rtc",
814 		.data = &s3c2443_rtc_data,
815 	}, {
816 		.compatible = "samsung,s3c6410-rtc",
817 		.data = &s3c6410_rtc_data,
818 	}, {
819 		.compatible = "samsung,exynos3250-rtc",
820 		.data = &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