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Merge tag 'trace-printf-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace...
[drm/drm-misc.git] / drivers / rtc / rtc-s3c.c
blobc0ac3bdb2f427df3ac218cecce3f3b61562d6d71
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/uaccess.h>
27 #include <linux/io.h>
28
29 #include <asm/irq.h>
30 #include "rtc-s3c.h"
31
32 struct s3c_rtc {
33 struct device *dev;
34 struct rtc_device *rtc;
35
36 void __iomem *base;
37 struct clk *rtc_clk;
38 struct clk *rtc_src_clk;
39 bool alarm_enabled;
40
41 const struct s3c_rtc_data *data;
42
43 int irq_alarm;
44 spinlock_t alarm_lock;
45
46 bool wake_en;
47 };
48
49 struct s3c_rtc_data {
50 bool needs_src_clk;
51
52 void (*irq_handler) (struct s3c_rtc *info, int mask);
53 void (*enable) (struct s3c_rtc *info);
54 void (*disable) (struct s3c_rtc *info);
55 };
56
57 static int s3c_rtc_enable_clk(struct s3c_rtc *info)
58 {
59 int ret;
60
61 ret = clk_enable(info->rtc_clk);
62 if (ret)
63 return ret;
64
65 if (info->data->needs_src_clk) {
66 ret = clk_enable(info->rtc_src_clk);
67 if (ret) {
68 clk_disable(info->rtc_clk);
69 return ret;
70 }
71 }
72 return 0;
73 }
74
75 static void s3c_rtc_disable_clk(struct s3c_rtc *info)
76 {
77 if (info->data->needs_src_clk)
78 clk_disable(info->rtc_src_clk);
79 clk_disable(info->rtc_clk);
80 }
81
82 /* IRQ Handler */
83 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
84 {
85 struct s3c_rtc *info = (struct s3c_rtc *)id;
86
87 if (info->data->irq_handler)
88 info->data->irq_handler(info, S3C2410_INTP_ALM);
89
90 return IRQ_HANDLED;
91 }
92
93 /* Update control registers */
94 static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
95 {
96 struct s3c_rtc *info = dev_get_drvdata(dev);
97 unsigned long flags;
98 unsigned int tmp;
99 int ret;
100
101 dev_dbg(info->dev, "%s: aie=%d\n", __func__, enabled);
102
103 ret = s3c_rtc_enable_clk(info);
104 if (ret)
105 return ret;
106
107 tmp = readb(info->base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
108
109 if (enabled)
110 tmp |= S3C2410_RTCALM_ALMEN;
111
112 writeb(tmp, info->base + S3C2410_RTCALM);
113
114 spin_lock_irqsave(&info->alarm_lock, flags);
115
116 if (info->alarm_enabled && !enabled)
117 s3c_rtc_disable_clk(info);
118 else if (!info->alarm_enabled && enabled)
119 ret = s3c_rtc_enable_clk(info);
120
121 info->alarm_enabled = enabled;
122 spin_unlock_irqrestore(&info->alarm_lock, flags);
123
124 s3c_rtc_disable_clk(info);
125
126 return ret;
127 }
128
129 /* Read time from RTC and convert it from BCD */
130 static int s3c_rtc_read_time(struct s3c_rtc *info, struct rtc_time *tm)
131 {
132 unsigned int have_retried = 0;
133 int ret;
134
135 ret = s3c_rtc_enable_clk(info);
136 if (ret)
137 return ret;
138
139 retry_get_time:
140 tm->tm_min = readb(info->base + S3C2410_RTCMIN);
141 tm->tm_hour = readb(info->base + S3C2410_RTCHOUR);
142 tm->tm_mday = readb(info->base + S3C2410_RTCDATE);
143 tm->tm_mon = readb(info->base + S3C2410_RTCMON);
144 tm->tm_year = readb(info->base + S3C2410_RTCYEAR);
145 tm->tm_sec = readb(info->base + S3C2410_RTCSEC);
146
147 /*
148 * The only way to work out whether the system was mid-update
149 * when we read it is to check the second counter, and if it
150 * is zero, then we re-try the entire read
151 */
152 if (tm->tm_sec == 0 && !have_retried) {
153 have_retried = 1;
154 goto retry_get_time;
155 }
156
157 s3c_rtc_disable_clk(info);
158
159 tm->tm_sec = bcd2bin(tm->tm_sec);
160 tm->tm_min = bcd2bin(tm->tm_min);
161 tm->tm_hour = bcd2bin(tm->tm_hour);
162 tm->tm_mday = bcd2bin(tm->tm_mday);
163 tm->tm_mon = bcd2bin(tm->tm_mon);
164 tm->tm_year = bcd2bin(tm->tm_year);
165
166 return 0;
167 }
168
169 /* Convert time to BCD and write it to RTC */
170 static int s3c_rtc_write_time(struct s3c_rtc *info, const struct rtc_time *tm)
171 {
172 int ret;
173
174 ret = s3c_rtc_enable_clk(info);
175 if (ret)
176 return ret;
177
178 writeb(bin2bcd(tm->tm_sec), info->base + S3C2410_RTCSEC);
179 writeb(bin2bcd(tm->tm_min), info->base + S3C2410_RTCMIN);
180 writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_RTCHOUR);
181 writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_RTCDATE);
182 writeb(bin2bcd(tm->tm_mon), info->base + S3C2410_RTCMON);
183 writeb(bin2bcd(tm->tm_year), info->base + S3C2410_RTCYEAR);
184
185 s3c_rtc_disable_clk(info);
186
187 return 0;
188 }
189
190 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *tm)
191 {
192 struct s3c_rtc *info = dev_get_drvdata(dev);
193 int ret;
194
195 ret = s3c_rtc_read_time(info, tm);
196 if (ret)
197 return ret;
198
199 /* Convert internal representation to actual date/time */
200 tm->tm_year += 100;
201 tm->tm_mon -= 1;
202
203 dev_dbg(dev, "read time %ptR\n", tm);
204 return 0;
205 }
206
207 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
208 {
209 struct s3c_rtc *info = dev_get_drvdata(dev);
210 struct rtc_time rtc_tm = *tm;
211
212 dev_dbg(dev, "set time %ptR\n", tm);
213
214 /*
215 * Convert actual date/time to internal representation.
216 * We get around Y2K by simply not supporting it.
217 */
218 rtc_tm.tm_year -= 100;
219 rtc_tm.tm_mon += 1;
220
221 return s3c_rtc_write_time(info, &rtc_tm);
222 }
223
224 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
225 {
226 struct s3c_rtc *info = dev_get_drvdata(dev);
227 struct rtc_time *alm_tm = &alrm->time;
228 unsigned int alm_en;
229 int ret;
230
231 ret = s3c_rtc_enable_clk(info);
232 if (ret)
233 return ret;
234
235 alm_tm->tm_sec = readb(info->base + S3C2410_ALMSEC);
236 alm_tm->tm_min = readb(info->base + S3C2410_ALMMIN);
237 alm_tm->tm_hour = readb(info->base + S3C2410_ALMHOUR);
238 alm_tm->tm_mon = readb(info->base + S3C2410_ALMMON);
239 alm_tm->tm_mday = readb(info->base + S3C2410_ALMDATE);
240 alm_tm->tm_year = readb(info->base + S3C2410_ALMYEAR);
241
242 alm_en = readb(info->base + S3C2410_RTCALM);
243
244 s3c_rtc_disable_clk(info);
245
246 alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
247
248 dev_dbg(dev, "read alarm %d, %ptR\n", alm_en, alm_tm);
249
250 /* decode the alarm enable field */
251 if (alm_en & S3C2410_RTCALM_SECEN)
252 alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
253
254 if (alm_en & S3C2410_RTCALM_MINEN)
255 alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
256
257 if (alm_en & S3C2410_RTCALM_HOUREN)
258 alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
259
260 if (alm_en & S3C2410_RTCALM_DAYEN)
261 alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
262
263 if (alm_en & S3C2410_RTCALM_MONEN) {
264 alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
265 alm_tm->tm_mon -= 1;
266 }
267
268 if (alm_en & S3C2410_RTCALM_YEAREN)
269 alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
270
271 return 0;
272 }
273
274 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
275 {
276 struct s3c_rtc *info = dev_get_drvdata(dev);
277 struct rtc_time *tm = &alrm->time;
278 unsigned int alrm_en;
279 int ret;
280
281 dev_dbg(dev, "s3c_rtc_setalarm: %d, %ptR\n", alrm->enabled, tm);
282
283 ret = s3c_rtc_enable_clk(info);
284 if (ret)
285 return ret;
286
287 alrm_en = readb(info->base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
288 writeb(0x00, info->base + S3C2410_RTCALM);
289
290 if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
291 alrm_en |= S3C2410_RTCALM_SECEN;
292 writeb(bin2bcd(tm->tm_sec), info->base + S3C2410_ALMSEC);
293 }
294
295 if (tm->tm_min < 60 && tm->tm_min >= 0) {
296 alrm_en |= S3C2410_RTCALM_MINEN;
297 writeb(bin2bcd(tm->tm_min), info->base + S3C2410_ALMMIN);
298 }
299
300 if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
301 alrm_en |= S3C2410_RTCALM_HOUREN;
302 writeb(bin2bcd(tm->tm_hour), info->base + S3C2410_ALMHOUR);
303 }
304
305 if (tm->tm_mon < 12 && tm->tm_mon >= 0) {
306 alrm_en |= S3C2410_RTCALM_MONEN;
307 writeb(bin2bcd(tm->tm_mon + 1), info->base + S3C2410_ALMMON);
308 }
309
310 if (tm->tm_mday <= 31 && tm->tm_mday >= 1) {
311 alrm_en |= S3C2410_RTCALM_DAYEN;
312 writeb(bin2bcd(tm->tm_mday), info->base + S3C2410_ALMDATE);
313 }
314
315 dev_dbg(dev, "setting S3C2410_RTCALM to %08x\n", alrm_en);
316
317 writeb(alrm_en, info->base + S3C2410_RTCALM);
318
319 s3c_rtc_setaie(dev, alrm->enabled);
320
321 s3c_rtc_disable_clk(info);
322
323 return 0;
324 }
325
326 static const struct rtc_class_ops s3c_rtcops = {
327 .read_time = s3c_rtc_gettime,
328 .set_time = s3c_rtc_settime,
329 .read_alarm = s3c_rtc_getalarm,
330 .set_alarm = s3c_rtc_setalarm,
331 .alarm_irq_enable = s3c_rtc_setaie,
332 };
333
334 static void s3c24xx_rtc_enable(struct s3c_rtc *info)
335 {
336 unsigned int con, tmp;
337
338 con = readw(info->base + S3C2410_RTCCON);
339 /* re-enable the device, and check it is ok */
340 if ((con & S3C2410_RTCCON_RTCEN) == 0) {
341 dev_info(info->dev, "rtc disabled, re-enabling\n");
342
343 tmp = readw(info->base + S3C2410_RTCCON);
344 writew(tmp | S3C2410_RTCCON_RTCEN, info->base + S3C2410_RTCCON);
345 }
346
347 if (con & S3C2410_RTCCON_CNTSEL) {
348 dev_info(info->dev, "removing RTCCON_CNTSEL\n");
349
350 tmp = readw(info->base + S3C2410_RTCCON);
351 writew(tmp & ~S3C2410_RTCCON_CNTSEL,
352 info->base + S3C2410_RTCCON);
353 }
354
355 if (con & S3C2410_RTCCON_CLKRST) {
356 dev_info(info->dev, "removing RTCCON_CLKRST\n");
357
358 tmp = readw(info->base + S3C2410_RTCCON);
359 writew(tmp & ~S3C2410_RTCCON_CLKRST,
360 info->base + S3C2410_RTCCON);
361 }
362 }
363
364 static void s3c24xx_rtc_disable(struct s3c_rtc *info)
365 {
366 unsigned int con;
367
368 con = readw(info->base + S3C2410_RTCCON);
369 con &= ~S3C2410_RTCCON_RTCEN;
370 writew(con, info->base + S3C2410_RTCCON);
371
372 con = readb(info->base + S3C2410_TICNT);
373 con &= ~S3C2410_TICNT_ENABLE;
374 writeb(con, info->base + S3C2410_TICNT);
375 }
376
377 static void s3c6410_rtc_disable(struct s3c_rtc *info)
378 {
379 unsigned int con;
380
381 con = readw(info->base + S3C2410_RTCCON);
382 con &= ~S3C64XX_RTCCON_TICEN;
383 con &= ~S3C2410_RTCCON_RTCEN;
384 writew(con, info->base + S3C2410_RTCCON);
385 }
386
387 static void s3c_rtc_remove(struct platform_device *pdev)
388 {
389 struct s3c_rtc *info = platform_get_drvdata(pdev);
390
391 s3c_rtc_setaie(info->dev, 0);
392
393 if (info->data->needs_src_clk)
394 clk_unprepare(info->rtc_src_clk);
395 clk_unprepare(info->rtc_clk);
396 }
397
398 static int s3c_rtc_probe(struct platform_device *pdev)
399 {
400 struct s3c_rtc *info = NULL;
401 int ret;
402
403 info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
404 if (!info)
405 return -ENOMEM;
406
407 info->dev = &pdev->dev;
408 info->data = of_device_get_match_data(&pdev->dev);
409 if (!info->data) {
410 dev_err(&pdev->dev, "failed getting s3c_rtc_data\n");
411 return -EINVAL;
412 }
413 spin_lock_init(&info->alarm_lock);
414
415 platform_set_drvdata(pdev, info);
416
417 info->irq_alarm = platform_get_irq(pdev, 0);
418 if (info->irq_alarm < 0)
419 return info->irq_alarm;
420
421 dev_dbg(&pdev->dev, "s3c2410_rtc: alarm irq %d\n", info->irq_alarm);
422
423 /* get the memory region */
424 info->base = devm_platform_ioremap_resource(pdev, 0);
425 if (IS_ERR(info->base))
426 return PTR_ERR(info->base);
427
428 info->rtc_clk = devm_clk_get(&pdev->dev, "rtc");
429 if (IS_ERR(info->rtc_clk))
430 return dev_err_probe(&pdev->dev, PTR_ERR(info->rtc_clk),
431 "failed to find rtc clock\n");
432 ret = clk_prepare_enable(info->rtc_clk);
433 if (ret)
434 return ret;
435
436 if (info->data->needs_src_clk) {
437 info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
438 if (IS_ERR(info->rtc_src_clk)) {
439 ret = dev_err_probe(&pdev->dev, PTR_ERR(info->rtc_src_clk),
440 "failed to find rtc source clock\n");
441 goto err_src_clk;
442 }
443 ret = clk_prepare_enable(info->rtc_src_clk);
444 if (ret)
445 goto err_src_clk;
446 }
447
448 /* disable RTC enable bits potentially set by the bootloader */
449 if (info->data->disable)
450 info->data->disable(info);
451
452 /* check to see if everything is setup correctly */
453 if (info->data->enable)
454 info->data->enable(info);
455
456 dev_dbg(&pdev->dev, "s3c2410_rtc: RTCCON=%02x\n",
457 readw(info->base + S3C2410_RTCCON));
458
459 device_init_wakeup(&pdev->dev, 1);
460
461 info->rtc = devm_rtc_allocate_device(&pdev->dev);
462 if (IS_ERR(info->rtc)) {
463 ret = PTR_ERR(info->rtc);
464 goto err_nortc;
465 }
466
467 info->rtc->ops = &s3c_rtcops;
468 info->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
469 info->rtc->range_max = RTC_TIMESTAMP_END_2099;
470
471 ret = devm_rtc_register_device(info->rtc);
472 if (ret)
473 goto err_nortc;
474
475 ret = devm_request_irq(&pdev->dev, info->irq_alarm, s3c_rtc_alarmirq,
476 0, "s3c2410-rtc alarm", info);
477 if (ret) {
478 dev_err(&pdev->dev, "IRQ%d error %d\n", info->irq_alarm, ret);
479 goto err_nortc;
480 }
481
482 s3c_rtc_disable_clk(info);
483
484 return 0;
485
486 err_nortc:
487 if (info->data->disable)
488 info->data->disable(info);
489
490 if (info->data->needs_src_clk)
491 clk_disable_unprepare(info->rtc_src_clk);
492 err_src_clk:
493 clk_disable_unprepare(info->rtc_clk);
494
495 return ret;
496 }
497
498 #ifdef CONFIG_PM_SLEEP
499
500 static int s3c_rtc_suspend(struct device *dev)
501 {
502 struct s3c_rtc *info = dev_get_drvdata(dev);
503 int ret;
504
505 ret = s3c_rtc_enable_clk(info);
506 if (ret)
507 return ret;
508
509 if (info->data->disable)
510 info->data->disable(info);
511
512 if (device_may_wakeup(dev) && !info->wake_en) {
513 if (enable_irq_wake(info->irq_alarm) == 0)
514 info->wake_en = true;
515 else
516 dev_err(dev, "enable_irq_wake failed\n");
517 }
518
519 return 0;
520 }
521
522 static int s3c_rtc_resume(struct device *dev)
523 {
524 struct s3c_rtc *info = dev_get_drvdata(dev);
525
526 if (info->data->enable)
527 info->data->enable(info);
528
529 s3c_rtc_disable_clk(info);
530
531 if (device_may_wakeup(dev) && info->wake_en) {
532 disable_irq_wake(info->irq_alarm);
533 info->wake_en = false;
534 }
535
536 return 0;
537 }
538 #endif
539 static SIMPLE_DEV_PM_OPS(s3c_rtc_pm_ops, s3c_rtc_suspend, s3c_rtc_resume);
540
541 static void s3c24xx_rtc_irq(struct s3c_rtc *info, int mask)
542 {
543 rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
544 }
545
546 static void s3c6410_rtc_irq(struct s3c_rtc *info, int mask)
547 {
548 rtc_update_irq(info->rtc, 1, RTC_AF | RTC_IRQF);
549 writeb(mask, info->base + S3C2410_INTP);
550 }
551
552 static struct s3c_rtc_data const s3c2410_rtc_data = {
553 .irq_handler = s3c24xx_rtc_irq,
554 .enable = s3c24xx_rtc_enable,
555 .disable = s3c24xx_rtc_disable,
556 };
557
558 static struct s3c_rtc_data const s3c2416_rtc_data = {
559 .irq_handler = s3c24xx_rtc_irq,
560 .enable = s3c24xx_rtc_enable,
561 .disable = s3c24xx_rtc_disable,
562 };
563
564 static struct s3c_rtc_data const s3c2443_rtc_data = {
565 .irq_handler = s3c24xx_rtc_irq,
566 .enable = s3c24xx_rtc_enable,
567 .disable = s3c24xx_rtc_disable,
568 };
569
570 static struct s3c_rtc_data const s3c6410_rtc_data = {
571 .needs_src_clk = true,
572 .irq_handler = s3c6410_rtc_irq,
573 .enable = s3c24xx_rtc_enable,
574 .disable = s3c6410_rtc_disable,
575 };
576
577 static const __maybe_unused struct of_device_id s3c_rtc_dt_match[] = {
578 {
579 .compatible = "samsung,s3c2410-rtc",
580 .data = &s3c2410_rtc_data,
581 }, {
582 .compatible = "samsung,s3c2416-rtc",
583 .data = &s3c2416_rtc_data,
584 }, {
585 .compatible = "samsung,s3c2443-rtc",
586 .data = &s3c2443_rtc_data,
587 }, {
588 .compatible = "samsung,s3c6410-rtc",
589 .data = &s3c6410_rtc_data,
590 }, {
591 .compatible = "samsung,exynos3250-rtc",
592 .data = &s3c6410_rtc_data,
593 },
594 { /* sentinel */ },
595 };
596 MODULE_DEVICE_TABLE(of, s3c_rtc_dt_match);
597
598 static struct platform_driver s3c_rtc_driver = {
599 .probe = s3c_rtc_probe,
600 .remove = s3c_rtc_remove,
601 .driver = {
602 .name = "s3c-rtc",
603 .pm = &s3c_rtc_pm_ops,
604 .of_match_table = of_match_ptr(s3c_rtc_dt_match),
605 },
606 };
607 module_platform_driver(s3c_rtc_driver);
608
609 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
610 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
611 MODULE_LICENSE("GPL");
612 MODULE_ALIAS("platform:s3c2410-rtc");
Kernel DRM miscellaneous fixes and cross-tree changes