xref: /linux/drivers/rtc/rtc-s3c.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
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 enabled;
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_alarm_clk_enable(struct s3c_rtc *info, bool enable)
71 {
72 	unsigned long irq_flags;
73 
74 	spin_lock_irqsave(&info->alarm_clk_lock, irq_flags);
75 	if (enable) {
76 		if (!info->enabled) {
77 			clk_enable(info->rtc_clk);
78 			if (info->data->needs_src_clk)
79 				clk_enable(info->rtc_src_clk);
80 			info->enabled = true;
81 		}
82 	} else {
83 		if (info->enabled) {
84 			if (info->data->needs_src_clk)
85 				clk_disable(info->rtc_src_clk);
86 			clk_disable(info->rtc_clk);
87 			info->enabled = false;
88 		}
89 	}
90 	spin_unlock_irqrestore(&info->alarm_clk_lock, irq_flags);
91 }
92 
93 /* IRQ Handlers */
94 static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
95 {
96 	struct s3c_rtc *info = (struct s3c_rtc *)id;
97 
98 	if (info->data->irq_handler)
99 		info->data->irq_handler(info, S3C2410_INTP_TIC);
100 
101 	return IRQ_HANDLED;
102 }
103 
104 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
105 {
106 	struct s3c_rtc *info = (struct s3c_rtc *)id;
107 
108 	if (info->data->irq_handler)
109 		info->data->irq_handler(info, S3C2410_INTP_ALM);
110 
111 	return IRQ_HANDLED;
112 }
113 
114 /* Update control registers */
115 static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
116 {
117 	struct s3c_rtc *info = dev_get_drvdata(dev);
118 	unsigned int tmp;
119 
120 	dev_dbg(info->dev, "%s: aie=%d\n", __func__, enabled);
121 
122 	clk_enable(info->rtc_clk);
123 	if (info->data->needs_src_clk)
124 		clk_enable(info->rtc_src_clk);
125 	tmp = readb(info->base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
126 
127 	if (enabled)
128 		tmp |= S3C2410_RTCALM_ALMEN;
129 
130 	writeb(tmp, info->base + S3C2410_RTCALM);
131 	if (info->data->needs_src_clk)
132 		clk_disable(info->rtc_src_clk);
133 	clk_disable(info->rtc_clk);
134 
135 	s3c_rtc_alarm_clk_enable(info, enabled);
136 
137 	return 0;
138 }
139 
140 /* Set RTC frequency */
141 static int s3c_rtc_setfreq(struct s3c_rtc *info, int freq)
142 {
143 	if (!is_power_of_2(freq))
144 		return -EINVAL;
145 
146 	clk_enable(info->rtc_clk);
147 	if (info->data->needs_src_clk)
148 		clk_enable(info->rtc_src_clk);
149 	spin_lock_irq(&info->pie_lock);
150 
151 	if (info->data->set_freq)
152 		info->data->set_freq(info, freq);
153 
154 	spin_unlock_irq(&info->pie_lock);
155 	if (info->data->needs_src_clk)
156 		clk_disable(info->rtc_src_clk);
157 	clk_disable(info->rtc_clk);
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 	clk_enable(info->rtc_clk);
169 	if (info->data->needs_src_clk)
170 		clk_enable(info->rtc_src_clk);
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 	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 	if (info->data->needs_src_clk)
206 		clk_disable(info->rtc_src_clk);
207 	clk_disable(info->rtc_clk);
208 
209 	return rtc_valid_tm(rtc_tm);
210 }
211 
212 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
213 {
214 	struct s3c_rtc *info = dev_get_drvdata(dev);
215 	int year = tm->tm_year - 100;
216 
217 	dev_dbg(dev, "set time %04d.%02d.%02d %02d:%02d:%02d\n",
218 		 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
219 		 tm->tm_hour, tm->tm_min, tm->tm_sec);
220 
221 	/* we get around y2k by simply not supporting it */
222 
223 	if (year < 0 || year >= 100) {
224 		dev_err(dev, "rtc only supports 100 years\n");
225 		return -EINVAL;
226 	}
227 
228 	clk_enable(info->rtc_clk);
229 	if (info->data->needs_src_clk)
230 		clk_enable(info->rtc_src_clk);
231 
232 	writeb(bin2bcd(tm->tm_sec),  info->base + S3C2410_RTCSEC);
233 	writeb(bin2bcd(tm->tm_min),  info->base + S3C2410_RTCMIN);
234 	writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_RTCHOUR);
235 	writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_RTCDATE);
236 	writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_RTCMON);
237 	writeb(bin2bcd(year), info->base + S3C2410_RTCYEAR);
238 
239 	if (info->data->needs_src_clk)
240 		clk_disable(info->rtc_src_clk);
241 	clk_disable(info->rtc_clk);
242 
243 	return 0;
244 }
245 
246 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
247 {
248 	struct s3c_rtc *info = dev_get_drvdata(dev);
249 	struct rtc_time *alm_tm = &alrm->time;
250 	unsigned int alm_en;
251 
252 	clk_enable(info->rtc_clk);
253 	if (info->data->needs_src_clk)
254 		clk_enable(info->rtc_src_clk);
255 
256 	alm_tm->tm_sec  = readb(info->base + S3C2410_ALMSEC);
257 	alm_tm->tm_min  = readb(info->base + S3C2410_ALMMIN);
258 	alm_tm->tm_hour = readb(info->base + S3C2410_ALMHOUR);
259 	alm_tm->tm_mon  = readb(info->base + S3C2410_ALMMON);
260 	alm_tm->tm_mday = readb(info->base + S3C2410_ALMDATE);
261 	alm_tm->tm_year = readb(info->base + S3C2410_ALMYEAR);
262 
263 	alm_en = readb(info->base + S3C2410_RTCALM);
264 
265 	alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
266 
267 	dev_dbg(dev, "read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
268 		 alm_en,
269 		 1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
270 		 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
271 
272 
273 	/* decode the alarm enable field */
274 
275 	if (alm_en & S3C2410_RTCALM_SECEN)
276 		alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
277 	else
278 		alm_tm->tm_sec = -1;
279 
280 	if (alm_en & S3C2410_RTCALM_MINEN)
281 		alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
282 	else
283 		alm_tm->tm_min = -1;
284 
285 	if (alm_en & S3C2410_RTCALM_HOUREN)
286 		alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
287 	else
288 		alm_tm->tm_hour = -1;
289 
290 	if (alm_en & S3C2410_RTCALM_DAYEN)
291 		alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
292 	else
293 		alm_tm->tm_mday = -1;
294 
295 	if (alm_en & S3C2410_RTCALM_MONEN) {
296 		alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
297 		alm_tm->tm_mon -= 1;
298 	} else {
299 		alm_tm->tm_mon = -1;
300 	}
301 
302 	if (alm_en & S3C2410_RTCALM_YEAREN)
303 		alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
304 	else
305 		alm_tm->tm_year = -1;
306 
307 	if (info->data->needs_src_clk)
308 		clk_disable(info->rtc_src_clk);
309 	clk_disable(info->rtc_clk);
310 
311 	return 0;
312 }
313 
314 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
315 {
316 	struct s3c_rtc *info = dev_get_drvdata(dev);
317 	struct rtc_time *tm = &alrm->time;
318 	unsigned int alrm_en;
319 
320 	clk_enable(info->rtc_clk);
321 	if (info->data->needs_src_clk)
322 		clk_enable(info->rtc_src_clk);
323 
324 	dev_dbg(dev, "s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
325 		 alrm->enabled,
326 		 1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
327 		 tm->tm_hour, tm->tm_min, tm->tm_sec);
328 
329 	alrm_en = readb(info->base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
330 	writeb(0x00, info->base + S3C2410_RTCALM);
331 
332 	if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
333 		alrm_en |= S3C2410_RTCALM_SECEN;
334 		writeb(bin2bcd(tm->tm_sec), info->base + S3C2410_ALMSEC);
335 	}
336 
337 	if (tm->tm_min < 60 && tm->tm_min >= 0) {
338 		alrm_en |= S3C2410_RTCALM_MINEN;
339 		writeb(bin2bcd(tm->tm_min), info->base + S3C2410_ALMMIN);
340 	}
341 
342 	if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
343 		alrm_en |= S3C2410_RTCALM_HOUREN;
344 		writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_ALMHOUR);
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_setaie(dev, alrm->enabled);
352 
353 	if (info->data->needs_src_clk)
354 		clk_disable(info->rtc_src_clk);
355 	clk_disable(info->rtc_clk);
356 
357 	return 0;
358 }
359 
360 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
361 {
362 	struct s3c_rtc *info = dev_get_drvdata(dev);
363 
364 	clk_enable(info->rtc_clk);
365 	if (info->data->needs_src_clk)
366 		clk_enable(info->rtc_src_clk);
367 
368 	if (info->data->enable_tick)
369 		info->data->enable_tick(info, seq);
370 
371 	if (info->data->needs_src_clk)
372 		clk_disable(info->rtc_src_clk);
373 	clk_disable(info->rtc_clk);
374 
375 	return 0;
376 }
377 
378 static const struct rtc_class_ops s3c_rtcops = {
379 	.read_time	= s3c_rtc_gettime,
380 	.set_time	= s3c_rtc_settime,
381 	.read_alarm	= s3c_rtc_getalarm,
382 	.set_alarm	= s3c_rtc_setalarm,
383 	.proc		= s3c_rtc_proc,
384 	.alarm_irq_enable = s3c_rtc_setaie,
385 };
386 
387 static void s3c24xx_rtc_enable(struct s3c_rtc *info)
388 {
389 	unsigned int con, tmp;
390 
391 	clk_enable(info->rtc_clk);
392 	if (info->data->needs_src_clk)
393 		clk_enable(info->rtc_src_clk);
394 
395 	con = readw(info->base + S3C2410_RTCCON);
396 	/* re-enable the device, and check it is ok */
397 	if ((con & S3C2410_RTCCON_RTCEN) == 0) {
398 		dev_info(info->dev, "rtc disabled, re-enabling\n");
399 
400 		tmp = readw(info->base + S3C2410_RTCCON);
401 		writew(tmp | S3C2410_RTCCON_RTCEN,
402 			info->base + S3C2410_RTCCON);
403 	}
404 
405 	if (con & S3C2410_RTCCON_CNTSEL) {
406 		dev_info(info->dev, "removing RTCCON_CNTSEL\n");
407 
408 		tmp = readw(info->base + S3C2410_RTCCON);
409 		writew(tmp & ~S3C2410_RTCCON_CNTSEL,
410 			info->base + S3C2410_RTCCON);
411 	}
412 
413 	if (con & S3C2410_RTCCON_CLKRST) {
414 		dev_info(info->dev, "removing RTCCON_CLKRST\n");
415 
416 		tmp = readw(info->base + S3C2410_RTCCON);
417 		writew(tmp & ~S3C2410_RTCCON_CLKRST,
418 			info->base + S3C2410_RTCCON);
419 	}
420 
421 	if (info->data->needs_src_clk)
422 		clk_disable(info->rtc_src_clk);
423 	clk_disable(info->rtc_clk);
424 }
425 
426 static void s3c24xx_rtc_disable(struct s3c_rtc *info)
427 {
428 	unsigned int con;
429 
430 	clk_enable(info->rtc_clk);
431 	if (info->data->needs_src_clk)
432 		clk_enable(info->rtc_src_clk);
433 
434 	con = readw(info->base + S3C2410_RTCCON);
435 	con &= ~S3C2410_RTCCON_RTCEN;
436 	writew(con, info->base + S3C2410_RTCCON);
437 
438 	con = readb(info->base + S3C2410_TICNT);
439 	con &= ~S3C2410_TICNT_ENABLE;
440 	writeb(con, info->base + S3C2410_TICNT);
441 
442 	if (info->data->needs_src_clk)
443 		clk_disable(info->rtc_src_clk);
444 	clk_disable(info->rtc_clk);
445 }
446 
447 static void s3c6410_rtc_disable(struct s3c_rtc *info)
448 {
449 	unsigned int con;
450 
451 	clk_enable(info->rtc_clk);
452 	if (info->data->needs_src_clk)
453 		clk_enable(info->rtc_src_clk);
454 
455 	con = readw(info->base + S3C2410_RTCCON);
456 	con &= ~S3C64XX_RTCCON_TICEN;
457 	con &= ~S3C2410_RTCCON_RTCEN;
458 	writew(con, info->base + S3C2410_RTCCON);
459 
460 	if (info->data->needs_src_clk)
461 		clk_disable(info->rtc_src_clk);
462 	clk_disable(info->rtc_clk);
463 }
464 
465 static int s3c_rtc_remove(struct platform_device *pdev)
466 {
467 	struct s3c_rtc *info = platform_get_drvdata(pdev);
468 
469 	s3c_rtc_setaie(info->dev, 0);
470 
471 	clk_unprepare(info->rtc_clk);
472 	info->rtc_clk = NULL;
473 
474 	return 0;
475 }
476 
477 static const struct of_device_id s3c_rtc_dt_match[];
478 
479 static struct s3c_rtc_data *s3c_rtc_get_data(struct platform_device *pdev)
480 {
481 	const struct of_device_id *match;
482 
483 	match = of_match_node(s3c_rtc_dt_match, pdev->dev.of_node);
484 	return (struct s3c_rtc_data *)match->data;
485 }
486 
487 static int s3c_rtc_probe(struct platform_device *pdev)
488 {
489 	struct s3c_rtc *info = NULL;
490 	struct rtc_time rtc_tm;
491 	struct resource *res;
492 	int ret;
493 
494 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
495 	if (!info)
496 		return -ENOMEM;
497 
498 	/* find the IRQs */
499 	info->irq_tick = platform_get_irq(pdev, 1);
500 	if (info->irq_tick < 0) {
501 		dev_err(&pdev->dev, "no irq for rtc tick\n");
502 		return info->irq_tick;
503 	}
504 
505 	info->dev = &pdev->dev;
506 	info->data = s3c_rtc_get_data(pdev);
507 	if (!info->data) {
508 		dev_err(&pdev->dev, "failed getting s3c_rtc_data\n");
509 		return -EINVAL;
510 	}
511 	spin_lock_init(&info->pie_lock);
512 	spin_lock_init(&info->alarm_clk_lock);
513 
514 	platform_set_drvdata(pdev, info);
515 
516 	info->irq_alarm = platform_get_irq(pdev, 0);
517 	if (info->irq_alarm < 0) {
518 		dev_err(&pdev->dev, "no irq for alarm\n");
519 		return info->irq_alarm;
520 	}
521 
522 	dev_dbg(&pdev->dev, "s3c2410_rtc: tick irq %d, alarm irq %d\n",
523 		 info->irq_tick, info->irq_alarm);
524 
525 	/* get the memory region */
526 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
527 	info->base = devm_ioremap_resource(&pdev->dev, res);
528 	if (IS_ERR(info->base))
529 		return PTR_ERR(info->base);
530 
531 	info->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
532 	if (IS_ERR(info->rtc_clk)) {
533 		dev_err(&pdev->dev, "failed to find rtc clock\n");
534 		return PTR_ERR(info->rtc_clk);
535 	}
536 	clk_prepare_enable(info->rtc_clk);
537 
538 	if (info->data->needs_src_clk) {
539 		info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
540 		if (IS_ERR(info->rtc_src_clk)) {
541 			dev_err(&pdev->dev,
542 				"failed to find rtc source clock\n");
543 			return PTR_ERR(info->rtc_src_clk);
544 		}
545 		clk_prepare_enable(info->rtc_src_clk);
546 	}
547 
548 	/* check to see if everything is setup correctly */
549 	if (info->data->enable)
550 		info->data->enable(info);
551 
552 	dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n",
553 		 readw(info->base + S3C2410_RTCCON));
554 
555 	device_init_wakeup(&pdev->dev, 1);
556 
557 	/* register RTC and exit */
558 	info->rtc = devm_rtc_device_register(&pdev->dev, "s3c", &s3c_rtcops,
559 				  THIS_MODULE);
560 	if (IS_ERR(info->rtc)) {
561 		dev_err(&pdev->dev, "cannot attach rtc\n");
562 		ret = PTR_ERR(info->rtc);
563 		goto err_nortc;
564 	}
565 
566 	ret = devm_request_irq(&pdev->dev, info->irq_alarm, s3c_rtc_alarmirq,
567 			  0,  "s3c2410-rtc alarm", info);
568 	if (ret) {
569 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_alarm, ret);
570 		goto err_nortc;
571 	}
572 
573 	ret = devm_request_irq(&pdev->dev, info->irq_tick, s3c_rtc_tickirq,
574 			  0,  "s3c2410-rtc tick", info);
575 	if (ret) {
576 		dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_tick, ret);
577 		goto err_nortc;
578 	}
579 
580 	/* Check RTC Time */
581 	s3c_rtc_gettime(&pdev->dev, &rtc_tm);
582 
583 	if (rtc_valid_tm(&rtc_tm)) {
584 		rtc_tm.tm_year	= 100;
585 		rtc_tm.tm_mon	= 0;
586 		rtc_tm.tm_mday	= 1;
587 		rtc_tm.tm_hour	= 0;
588 		rtc_tm.tm_min	= 0;
589 		rtc_tm.tm_sec	= 0;
590 
591 		s3c_rtc_settime(&pdev->dev, &rtc_tm);
592 
593 		dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
594 	}
595 
596 	if (info->data->select_tick_clk)
597 		info->data->select_tick_clk(info);
598 
599 	s3c_rtc_setfreq(info, 1);
600 
601 	if (info->data->needs_src_clk)
602 		clk_disable(info->rtc_src_clk);
603 	clk_disable(info->rtc_clk);
604 
605 	return 0;
606 
607  err_nortc:
608 	if (info->data->disable)
609 		info->data->disable(info);
610 	clk_disable_unprepare(info->rtc_clk);
611 
612 	return ret;
613 }
614 
615 #ifdef CONFIG_PM_SLEEP
616 
617 static int s3c_rtc_suspend(struct device *dev)
618 {
619 	struct s3c_rtc *info = dev_get_drvdata(dev);
620 
621 	clk_enable(info->rtc_clk);
622 	if (info->data->needs_src_clk)
623 		clk_enable(info->rtc_src_clk);
624 
625 	/* save TICNT for anyone using periodic interrupts */
626 	if (info->data->save_tick_cnt)
627 		info->data->save_tick_cnt(info);
628 
629 	if (info->data->disable)
630 		info->data->disable(info);
631 
632 	if (device_may_wakeup(dev) && !info->wake_en) {
633 		if (enable_irq_wake(info->irq_alarm) == 0)
634 			info->wake_en = true;
635 		else
636 			dev_err(dev, "enable_irq_wake failed\n");
637 	}
638 
639 	if (info->data->needs_src_clk)
640 		clk_disable(info->rtc_src_clk);
641 	clk_disable(info->rtc_clk);
642 
643 	return 0;
644 }
645 
646 static int s3c_rtc_resume(struct device *dev)
647 {
648 	struct s3c_rtc *info = dev_get_drvdata(dev);
649 
650 	clk_enable(info->rtc_clk);
651 	if (info->data->needs_src_clk)
652 		clk_enable(info->rtc_src_clk);
653 
654 	if (info->data->enable)
655 		info->data->enable(info);
656 
657 	if (info->data->restore_tick_cnt)
658 		info->data->restore_tick_cnt(info);
659 
660 	if (device_may_wakeup(dev) && info->wake_en) {
661 		disable_irq_wake(info->irq_alarm);
662 		info->wake_en = false;
663 	}
664 
665 	if (info->data->needs_src_clk)
666 		clk_disable(info->rtc_src_clk);
667 	clk_disable(info->rtc_clk);
668 
669 	return 0;
670 }
671 #endif
672 static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume);
673 
674 static void s3c24xx_rtc_irq(struct s3c_rtc *info, int mask)
675 {
676 	clk_enable(info->rtc_clk);
677 	if (info->data->needs_src_clk)
678 		clk_enable(info->rtc_src_clk);
679 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
680 	if (info->data->needs_src_clk)
681 		clk_disable(info->rtc_src_clk);
682 	clk_disable(info->rtc_clk);
683 
684 	s3c_rtc_alarm_clk_enable(info, false);
685 }
686 
687 static void s3c6410_rtc_irq(struct s3c_rtc *info, int mask)
688 {
689 	clk_enable(info->rtc_clk);
690 	if (info->data->needs_src_clk)
691 		clk_enable(info->rtc_src_clk);
692 	rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
693 	writeb(mask, info->base + S3C2410_INTP);
694 	if (info->data->needs_src_clk)
695 		clk_disable(info->rtc_src_clk);
696 	clk_disable(info->rtc_clk);
697 
698 	s3c_rtc_alarm_clk_enable(info, false);
699 }
700 
701 static void s3c2410_rtc_setfreq(struct s3c_rtc *info, int freq)
702 {
703 	unsigned int tmp = 0;
704 	int val;
705 
706 	tmp = readb(info->base + S3C2410_TICNT);
707 	tmp &= S3C2410_TICNT_ENABLE;
708 
709 	val = (info->rtc->max_user_freq / freq) - 1;
710 	tmp |= val;
711 
712 	writel(tmp, info->base + S3C2410_TICNT);
713 }
714 
715 static void s3c2416_rtc_setfreq(struct s3c_rtc *info, int freq)
716 {
717 	unsigned int tmp = 0;
718 	int val;
719 
720 	tmp = readb(info->base + S3C2410_TICNT);
721 	tmp &= S3C2410_TICNT_ENABLE;
722 
723 	val = (info->rtc->max_user_freq / freq) - 1;
724 
725 	tmp |= S3C2443_TICNT_PART(val);
726 	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
727 
728 	writel(S3C2416_TICNT2_PART(val), info->base + S3C2416_TICNT2);
729 
730 	writel(tmp, info->base + S3C2410_TICNT);
731 }
732 
733 static void s3c2443_rtc_setfreq(struct s3c_rtc *info, int freq)
734 {
735 	unsigned int tmp = 0;
736 	int val;
737 
738 	tmp = readb(info->base + S3C2410_TICNT);
739 	tmp &= S3C2410_TICNT_ENABLE;
740 
741 	val = (info->rtc->max_user_freq / freq) - 1;
742 
743 	tmp |= S3C2443_TICNT_PART(val);
744 	writel(S3C2443_TICNT1_PART(val), info->base + S3C2443_TICNT1);
745 
746 	writel(tmp, info->base + S3C2410_TICNT);
747 }
748 
749 static void s3c6410_rtc_setfreq(struct s3c_rtc *info, int freq)
750 {
751 	int val;
752 
753 	val = (info->rtc->max_user_freq / freq) - 1;
754 	writel(val, info->base + S3C2410_TICNT);
755 }
756 
757 static void s3c24xx_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
758 {
759 	unsigned int ticnt;
760 
761 	ticnt = readb(info->base + S3C2410_TICNT);
762 	ticnt &= S3C2410_TICNT_ENABLE;
763 
764 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
765 }
766 
767 static void s3c2416_rtc_select_tick_clk(struct s3c_rtc *info)
768 {
769 	unsigned int con;
770 
771 	con = readw(info->base + S3C2410_RTCCON);
772 	con |= S3C2443_RTCCON_TICSEL;
773 	writew(con, info->base + S3C2410_RTCCON);
774 }
775 
776 static void s3c6410_rtc_enable_tick(struct s3c_rtc *info, struct seq_file *seq)
777 {
778 	unsigned int ticnt;
779 
780 	ticnt = readw(info->base + S3C2410_RTCCON);
781 	ticnt &= S3C64XX_RTCCON_TICEN;
782 
783 	seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt  ? "yes" : "no");
784 }
785 
786 static void s3c24xx_rtc_save_tick_cnt(struct s3c_rtc *info)
787 {
788 	info->ticnt_save = readb(info->base + S3C2410_TICNT);
789 }
790 
791 static void s3c24xx_rtc_restore_tick_cnt(struct s3c_rtc *info)
792 {
793 	writeb(info->ticnt_save, info->base + S3C2410_TICNT);
794 }
795 
796 static void s3c6410_rtc_save_tick_cnt(struct s3c_rtc *info)
797 {
798 	info->ticnt_en_save = readw(info->base + S3C2410_RTCCON);
799 	info->ticnt_en_save &= S3C64XX_RTCCON_TICEN;
800 	info->ticnt_save = readl(info->base + S3C2410_TICNT);
801 }
802 
803 static void s3c6410_rtc_restore_tick_cnt(struct s3c_rtc *info)
804 {
805 	unsigned int con;
806 
807 	writel(info->ticnt_save, info->base + S3C2410_TICNT);
808 	if (info->ticnt_en_save) {
809 		con = readw(info->base + S3C2410_RTCCON);
810 		writew(con | info->ticnt_en_save,
811 				info->base + S3C2410_RTCCON);
812 	}
813 }
814 
815 static struct s3c_rtc_data const s3c2410_rtc_data = {
816 	.max_user_freq		= 128,
817 	.irq_handler		= s3c24xx_rtc_irq,
818 	.set_freq		= s3c2410_rtc_setfreq,
819 	.enable_tick		= s3c24xx_rtc_enable_tick,
820 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
821 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
822 	.enable			= s3c24xx_rtc_enable,
823 	.disable		= s3c24xx_rtc_disable,
824 };
825 
826 static struct s3c_rtc_data const s3c2416_rtc_data = {
827 	.max_user_freq		= 32768,
828 	.irq_handler		= s3c24xx_rtc_irq,
829 	.set_freq		= s3c2416_rtc_setfreq,
830 	.enable_tick		= s3c24xx_rtc_enable_tick,
831 	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
832 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
833 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
834 	.enable			= s3c24xx_rtc_enable,
835 	.disable		= s3c24xx_rtc_disable,
836 };
837 
838 static struct s3c_rtc_data const s3c2443_rtc_data = {
839 	.max_user_freq		= 32768,
840 	.irq_handler		= s3c24xx_rtc_irq,
841 	.set_freq		= s3c2443_rtc_setfreq,
842 	.enable_tick		= s3c24xx_rtc_enable_tick,
843 	.select_tick_clk	= s3c2416_rtc_select_tick_clk,
844 	.save_tick_cnt		= s3c24xx_rtc_save_tick_cnt,
845 	.restore_tick_cnt	= s3c24xx_rtc_restore_tick_cnt,
846 	.enable			= s3c24xx_rtc_enable,
847 	.disable		= s3c24xx_rtc_disable,
848 };
849 
850 static struct s3c_rtc_data const s3c6410_rtc_data = {
851 	.max_user_freq		= 32768,
852 	.irq_handler		= s3c6410_rtc_irq,
853 	.set_freq		= s3c6410_rtc_setfreq,
854 	.enable_tick		= s3c6410_rtc_enable_tick,
855 	.save_tick_cnt		= s3c6410_rtc_save_tick_cnt,
856 	.restore_tick_cnt	= s3c6410_rtc_restore_tick_cnt,
857 	.enable			= s3c24xx_rtc_enable,
858 	.disable		= s3c6410_rtc_disable,
859 };
860 
861 static struct s3c_rtc_data const exynos3250_rtc_data = {
862 	.max_user_freq		= 32768,
863 	.needs_src_clk		= true,
864 	.irq_handler		= s3c6410_rtc_irq,
865 	.set_freq		= s3c6410_rtc_setfreq,
866 	.enable_tick		= s3c6410_rtc_enable_tick,
867 	.save_tick_cnt		= s3c6410_rtc_save_tick_cnt,
868 	.restore_tick_cnt	= s3c6410_rtc_restore_tick_cnt,
869 	.enable			= s3c24xx_rtc_enable,
870 	.disable		= s3c6410_rtc_disable,
871 };
872 
873 static const struct of_device_id s3c_rtc_dt_match[] = {
874 	{
875 		.compatible = "samsung,s3c2410-rtc",
876 		.data = (void *)&s3c2410_rtc_data,
877 	}, {
878 		.compatible = "samsung,s3c2416-rtc",
879 		.data = (void *)&s3c2416_rtc_data,
880 	}, {
881 		.compatible = "samsung,s3c2443-rtc",
882 		.data = (void *)&s3c2443_rtc_data,
883 	}, {
884 		.compatible = "samsung,s3c6410-rtc",
885 		.data = (void *)&s3c6410_rtc_data,
886 	}, {
887 		.compatible = "samsung,exynos3250-rtc",
888 		.data = (void *)&exynos3250_rtc_data,
889 	},
890 	{ /* sentinel */ },
891 };
892 MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
893 
894 static struct platform_driver s3c_rtc_driver = {
895 	.probe		= s3c_rtc_probe,
896 	.remove		= s3c_rtc_remove,
897 	.driver		= {
898 		.name	= "s3c-rtc",
899 		.pm	= &s3c_rtc_pm_ops,
900 		.of_match_table	= of_match_ptr(s3c_rtc_dt_match),
901 	},
902 };
903 module_platform_driver(s3c_rtc_driver);
904 
905 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
906 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
907 MODULE_LICENSE("GPL");
908 MODULE_ALIAS("platform:s3c2410-rtc");
909