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TTY: tty_io, annotate locking functions
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / rtc / rtc-s3c.c
blobb3466c491cd35cbbd93a64df0f1dbcf070c84e6c
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
29 #include <mach/hardware.h>
30 #include <asm/uaccess.h>
31 #include <asm/io.h>
32 #include <asm/irq.h>
33 #include <plat/regs-rtc.h>
34
35 enum s3c_cpu_type {
36 TYPE_S3C2410,
37 TYPE_S3C64XX,
38 };
39
40 /* I have yet to find an S3C implementation with more than one
41 * of these rtc blocks in */
42
43 static struct resource *s3c_rtc_mem;
44
45 static struct clk *rtc_clk;
46 static void __iomem *s3c_rtc_base;
47 static int s3c_rtc_alarmno = NO_IRQ;
48 static int s3c_rtc_tickno = NO_IRQ;
49 static enum s3c_cpu_type s3c_rtc_cpu_type;
50
51 static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
52
53 /* IRQ Handlers */
54
55 static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
56 {
57 struct rtc_device *rdev = id;
58
59 rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF);
60
61 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
62 writeb(S3C2410_INTP_ALM, s3c_rtc_base + S3C2410_INTP);
63
64 return IRQ_HANDLED;
65 }
66
67 static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
68 {
69 struct rtc_device *rdev = id;
70
71 rtc_update_irq(rdev, 1, RTC_PF | RTC_IRQF);
72
73 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
74 writeb(S3C2410_INTP_TIC, s3c_rtc_base + S3C2410_INTP);
75
76 return IRQ_HANDLED;
77 }
78
79 /* Update control registers */
80 static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
81 {
82 unsigned int tmp;
83
84 pr_debug("%s: aie=%d\n", __func__, enabled);
85
86 tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
87
88 if (enabled)
89 tmp |= S3C2410_RTCALM_ALMEN;
90
91 writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
92
93 return 0;
94 }
95
96 static int s3c_rtc_setfreq(struct device *dev, int freq)
97 {
98 struct platform_device *pdev = to_platform_device(dev);
99 struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
100 unsigned int tmp = 0;
101
102 if (!is_power_of_2(freq))
103 return -EINVAL;
104
105 spin_lock_irq(&s3c_rtc_pie_lock);
106
107 if (s3c_rtc_cpu_type == TYPE_S3C2410) {
108 tmp = readb(s3c_rtc_base + S3C2410_TICNT);
109 tmp &= S3C2410_TICNT_ENABLE;
110 }
111
112 tmp |= (rtc_dev->max_user_freq / freq)-1;
113
114 writel(tmp, s3c_rtc_base + S3C2410_TICNT);
115 spin_unlock_irq(&s3c_rtc_pie_lock);
116
117 return 0;
118 }
119
120 /* Time read/write */
121
122 static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
123 {
124 unsigned int have_retried = 0;
125 void __iomem *base = s3c_rtc_base;
126
127 retry_get_time:
128 rtc_tm->tm_min = readb(base + S3C2410_RTCMIN);
129 rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
130 rtc_tm->tm_mday = readb(base + S3C2410_RTCDATE);
131 rtc_tm->tm_mon = readb(base + S3C2410_RTCMON);
132 rtc_tm->tm_year = readb(base + S3C2410_RTCYEAR);
133 rtc_tm->tm_sec = readb(base + S3C2410_RTCSEC);
134
135 /* the only way to work out wether the system was mid-update
136 * when we read it is to check the second counter, and if it
137 * is zero, then we re-try the entire read
138 */
139
140 if (rtc_tm->tm_sec == 0 && !have_retried) {
141 have_retried = 1;
142 goto retry_get_time;
143 }
144
145 pr_debug("read time %04d.%02d.%02d %02d:%02d:%02d\n",
146 1900 + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
147 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
148
149 rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
150 rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
151 rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
152 rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
153 rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
154 rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
155
156 rtc_tm->tm_year += 100;
157 rtc_tm->tm_mon -= 1;
158
159 return rtc_valid_tm(rtc_tm);
160 }
161
162 static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
163 {
164 void __iomem *base = s3c_rtc_base;
165 int year = tm->tm_year - 100;
166
167 pr_debug("set time %04d.%02d.%02d %02d:%02d:%02d\n",
168 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
169 tm->tm_hour, tm->tm_min, tm->tm_sec);
170
171 /* we get around y2k by simply not supporting it */
172
173 if (year < 0 || year >= 100) {
174 dev_err(dev, "rtc only supports 100 years\n");
175 return -EINVAL;
176 }
177
178 writeb(bin2bcd(tm->tm_sec), base + S3C2410_RTCSEC);
179 writeb(bin2bcd(tm->tm_min), base + S3C2410_RTCMIN);
180 writeb(bin2bcd(tm->tm_hour), base + S3C2410_RTCHOUR);
181 writeb(bin2bcd(tm->tm_mday), base + S3C2410_RTCDATE);
182 writeb(bin2bcd(tm->tm_mon + 1), base + S3C2410_RTCMON);
183 writeb(bin2bcd(year), base + S3C2410_RTCYEAR);
184
185 return 0;
186 }
187
188 static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
189 {
190 struct rtc_time *alm_tm = &alrm->time;
191 void __iomem *base = s3c_rtc_base;
192 unsigned int alm_en;
193
194 alm_tm->tm_sec = readb(base + S3C2410_ALMSEC);
195 alm_tm->tm_min = readb(base + S3C2410_ALMMIN);
196 alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
197 alm_tm->tm_mon = readb(base + S3C2410_ALMMON);
198 alm_tm->tm_mday = readb(base + S3C2410_ALMDATE);
199 alm_tm->tm_year = readb(base + S3C2410_ALMYEAR);
200
201 alm_en = readb(base + S3C2410_RTCALM);
202
203 alrm->enabled = (alm_en & S3C2410_RTCALM_ALMEN) ? 1 : 0;
204
205 pr_debug("read alarm %d, %04d.%02d.%02d %02d:%02d:%02d\n",
206 alm_en,
207 1900 + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
208 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
209
210
211 /* decode the alarm enable field */
212
213 if (alm_en & S3C2410_RTCALM_SECEN)
214 alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
215 else
216 alm_tm->tm_sec = -1;
217
218 if (alm_en & S3C2410_RTCALM_MINEN)
219 alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
220 else
221 alm_tm->tm_min = -1;
222
223 if (alm_en & S3C2410_RTCALM_HOUREN)
224 alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
225 else
226 alm_tm->tm_hour = -1;
227
228 if (alm_en & S3C2410_RTCALM_DAYEN)
229 alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
230 else
231 alm_tm->tm_mday = -1;
232
233 if (alm_en & S3C2410_RTCALM_MONEN) {
234 alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon);
235 alm_tm->tm_mon -= 1;
236 } else {
237 alm_tm->tm_mon = -1;
238 }
239
240 if (alm_en & S3C2410_RTCALM_YEAREN)
241 alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
242 else
243 alm_tm->tm_year = -1;
244
245 return 0;
246 }
247
248 static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
249 {
250 struct rtc_time *tm = &alrm->time;
251 void __iomem *base = s3c_rtc_base;
252 unsigned int alrm_en;
253
254 pr_debug("s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
255 alrm->enabled,
256 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
257 tm->tm_hour, tm->tm_min, tm->tm_sec);
258
259
260 alrm_en = readb(base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN;
261 writeb(0x00, base + S3C2410_RTCALM);
262
263 if (tm->tm_sec < 60 && tm->tm_sec >= 0) {
264 alrm_en |= S3C2410_RTCALM_SECEN;
265 writeb(bin2bcd(tm->tm_sec), base + S3C2410_ALMSEC);
266 }
267
268 if (tm->tm_min < 60 && tm->tm_min >= 0) {
269 alrm_en |= S3C2410_RTCALM_MINEN;
270 writeb(bin2bcd(tm->tm_min), base + S3C2410_ALMMIN);
271 }
272
273 if (tm->tm_hour < 24 && tm->tm_hour >= 0) {
274 alrm_en |= S3C2410_RTCALM_HOUREN;
275 writeb(bin2bcd(tm->tm_hour), base + S3C2410_ALMHOUR);
276 }
277
278 pr_debug("setting S3C2410_RTCALM to %08x\n", alrm_en);
279
280 writeb(alrm_en, base + S3C2410_RTCALM);
281
282 s3c_rtc_setaie(dev, alrm->enabled);
283
284 return 0;
285 }
286
287 static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
288 {
289 unsigned int ticnt;
290
291 if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
292 ticnt = readw(s3c_rtc_base + S3C2410_RTCCON);
293 ticnt &= S3C64XX_RTCCON_TICEN;
294 } else {
295 ticnt = readb(s3c_rtc_base + S3C2410_TICNT);
296 ticnt &= S3C2410_TICNT_ENABLE;
297 }
298
299 seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt ? "yes" : "no");
300 return 0;
301 }
302
303 static int s3c_rtc_open(struct device *dev)
304 {
305 struct platform_device *pdev = to_platform_device(dev);
306 struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
307 int ret;
308
309 ret = request_irq(s3c_rtc_alarmno, s3c_rtc_alarmirq,
310 IRQF_DISABLED, "s3c2410-rtc alarm", rtc_dev);
311
312 if (ret) {
313 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_alarmno, ret);
314 return ret;
315 }
316
317 ret = request_irq(s3c_rtc_tickno, s3c_rtc_tickirq,
318 IRQF_DISABLED, "s3c2410-rtc tick", rtc_dev);
319
320 if (ret) {
321 dev_err(dev, "IRQ%d error %d\n", s3c_rtc_tickno, ret);
322 goto tick_err;
323 }
324
325 return ret;
326
327 tick_err:
328 free_irq(s3c_rtc_alarmno, rtc_dev);
329 return ret;
330 }
331
332 static void s3c_rtc_release(struct device *dev)
333 {
334 struct platform_device *pdev = to_platform_device(dev);
335 struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
336
337 /* do not clear AIE here, it may be needed for wake */
338
339 free_irq(s3c_rtc_alarmno, rtc_dev);
340 free_irq(s3c_rtc_tickno, rtc_dev);
341 }
342
343 static const struct rtc_class_ops s3c_rtcops = {
344 .open = s3c_rtc_open,
345 .release = s3c_rtc_release,
346 .read_time = s3c_rtc_gettime,
347 .set_time = s3c_rtc_settime,
348 .read_alarm = s3c_rtc_getalarm,
349 .set_alarm = s3c_rtc_setalarm,
350 .proc = s3c_rtc_proc,
351 .alarm_irq_enable = s3c_rtc_setaie,
352 };
353
354 static void s3c_rtc_enable(struct platform_device *pdev, int en)
355 {
356 void __iomem *base = s3c_rtc_base;
357 unsigned int tmp;
358
359 if (s3c_rtc_base == NULL)
360 return;
361
362 if (!en) {
363 tmp = readw(base + S3C2410_RTCCON);
364 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
365 tmp &= ~S3C64XX_RTCCON_TICEN;
366 tmp &= ~S3C2410_RTCCON_RTCEN;
367 writew(tmp, base + S3C2410_RTCCON);
368
369 if (s3c_rtc_cpu_type == TYPE_S3C2410) {
370 tmp = readb(base + S3C2410_TICNT);
371 tmp &= ~S3C2410_TICNT_ENABLE;
372 writeb(tmp, base + S3C2410_TICNT);
373 }
374 } else {
375 /* re-enable the device, and check it is ok */
376
377 if ((readw(base+S3C2410_RTCCON) & S3C2410_RTCCON_RTCEN) == 0) {
378 dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
379
380 tmp = readw(base + S3C2410_RTCCON);
381 writew(tmp | S3C2410_RTCCON_RTCEN,
382 base + S3C2410_RTCCON);
383 }
384
385 if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CNTSEL)) {
386 dev_info(&pdev->dev, "removing RTCCON_CNTSEL\n");
387
388 tmp = readw(base + S3C2410_RTCCON);
389 writew(tmp & ~S3C2410_RTCCON_CNTSEL,
390 base + S3C2410_RTCCON);
391 }
392
393 if ((readw(base + S3C2410_RTCCON) & S3C2410_RTCCON_CLKRST)) {
394 dev_info(&pdev->dev, "removing RTCCON_CLKRST\n");
395
396 tmp = readw(base + S3C2410_RTCCON);
397 writew(tmp & ~S3C2410_RTCCON_CLKRST,
398 base + S3C2410_RTCCON);
399 }
400 }
401 }
402
403 static int __devexit s3c_rtc_remove(struct platform_device *dev)
404 {
405 struct rtc_device *rtc = platform_get_drvdata(dev);
406
407 platform_set_drvdata(dev, NULL);
408 rtc_device_unregister(rtc);
409
410 s3c_rtc_setaie(&dev->dev, 0);
411
412 clk_disable(rtc_clk);
413 clk_put(rtc_clk);
414 rtc_clk = NULL;
415
416 iounmap(s3c_rtc_base);
417 release_resource(s3c_rtc_mem);
418 kfree(s3c_rtc_mem);
419
420 return 0;
421 }
422
423 static int __devinit s3c_rtc_probe(struct platform_device *pdev)
424 {
425 struct rtc_device *rtc;
426 struct rtc_time rtc_tm;
427 struct resource *res;
428 int ret;
429
430 pr_debug("%s: probe=%p\n", __func__, pdev);
431
432 /* find the IRQs */
433
434 s3c_rtc_tickno = platform_get_irq(pdev, 1);
435 if (s3c_rtc_tickno < 0) {
436 dev_err(&pdev->dev, "no irq for rtc tick\n");
437 return -ENOENT;
438 }
439
440 s3c_rtc_alarmno = platform_get_irq(pdev, 0);
441 if (s3c_rtc_alarmno < 0) {
442 dev_err(&pdev->dev, "no irq for alarm\n");
443 return -ENOENT;
444 }
445
446 pr_debug("s3c2410_rtc: tick irq %d, alarm irq %d\n",
447 s3c_rtc_tickno, s3c_rtc_alarmno);
448
449 /* get the memory region */
450
451 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
452 if (res == NULL) {
453 dev_err(&pdev->dev, "failed to get memory region resource\n");
454 return -ENOENT;
455 }
456
457 s3c_rtc_mem = request_mem_region(res->start,
458 res->end-res->start+1,
459 pdev->name);
460
461 if (s3c_rtc_mem == NULL) {
462 dev_err(&pdev->dev, "failed to reserve memory region\n");
463 ret = -ENOENT;
464 goto err_nores;
465 }
466
467 s3c_rtc_base = ioremap(res->start, res->end - res->start + 1);
468 if (s3c_rtc_base == NULL) {
469 dev_err(&pdev->dev, "failed ioremap()\n");
470 ret = -EINVAL;
471 goto err_nomap;
472 }
473
474 rtc_clk = clk_get(&pdev->dev, "rtc");
475 if (IS_ERR(rtc_clk)) {
476 dev_err(&pdev->dev, "failed to find rtc clock source\n");
477 ret = PTR_ERR(rtc_clk);
478 rtc_clk = NULL;
479 goto err_clk;
480 }
481
482 clk_enable(rtc_clk);
483
484 /* check to see if everything is setup correctly */
485
486 s3c_rtc_enable(pdev, 1);
487
488 pr_debug("s3c2410_rtc: RTCCON=%02x\n",
489 readw(s3c_rtc_base + S3C2410_RTCCON));
490
491 device_init_wakeup(&pdev->dev, 1);
492
493 /* register RTC and exit */
494
495 rtc = rtc_device_register("s3c", &pdev->dev, &s3c_rtcops,
496 THIS_MODULE);
497
498 if (IS_ERR(rtc)) {
499 dev_err(&pdev->dev, "cannot attach rtc\n");
500 ret = PTR_ERR(rtc);
501 goto err_nortc;
502 }
503
504 s3c_rtc_cpu_type = platform_get_device_id(pdev)->driver_data;
505
506 /* Check RTC Time */
507
508 s3c_rtc_gettime(NULL, &rtc_tm);
509
510 if (rtc_valid_tm(&rtc_tm)) {
511 rtc_tm.tm_year = 100;
512 rtc_tm.tm_mon = 0;
513 rtc_tm.tm_mday = 1;
514 rtc_tm.tm_hour = 0;
515 rtc_tm.tm_min = 0;
516 rtc_tm.tm_sec = 0;
517
518 s3c_rtc_settime(NULL, &rtc_tm);
519
520 dev_warn(&pdev->dev, "warning: invalid RTC value so initializing it\n");
521 }
522
523 if (s3c_rtc_cpu_type == TYPE_S3C64XX)
524 rtc->max_user_freq = 32768;
525 else
526 rtc->max_user_freq = 128;
527
528 platform_set_drvdata(pdev, rtc);
529
530 s3c_rtc_setfreq(&pdev->dev, 1);
531
532 return 0;
533
534 err_nortc:
535 s3c_rtc_enable(pdev, 0);
536 clk_disable(rtc_clk);
537 clk_put(rtc_clk);
538
539 err_clk:
540 iounmap(s3c_rtc_base);
541
542 err_nomap:
543 release_resource(s3c_rtc_mem);
544
545 err_nores:
546 return ret;
547 }
548
549 #ifdef CONFIG_PM
550
551 /* RTC Power management control */
552
553 static int ticnt_save, ticnt_en_save;
554
555 static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
556 {
557 /* save TICNT for anyone using periodic interrupts */
558 ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
559 if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
560 ticnt_en_save = readw(s3c_rtc_base + S3C2410_RTCCON);
561 ticnt_en_save &= S3C64XX_RTCCON_TICEN;
562 }
563 s3c_rtc_enable(pdev, 0);
564
565 if (device_may_wakeup(&pdev->dev))
566 enable_irq_wake(s3c_rtc_alarmno);
567
568 return 0;
569 }
570
571 static int s3c_rtc_resume(struct platform_device *pdev)
572 {
573 unsigned int tmp;
574
575 s3c_rtc_enable(pdev, 1);
576 writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
577 if (s3c_rtc_cpu_type == TYPE_S3C64XX && ticnt_en_save) {
578 tmp = readw(s3c_rtc_base + S3C2410_RTCCON);
579 writew(tmp | ticnt_en_save, s3c_rtc_base + S3C2410_RTCCON);
580 }
581
582 if (device_may_wakeup(&pdev->dev))
583 disable_irq_wake(s3c_rtc_alarmno);
584
585 return 0;
586 }
587 #else
588 #define s3c_rtc_suspend NULL
589 #define s3c_rtc_resume NULL
590 #endif
591
592 static struct platform_device_id s3c_rtc_driver_ids[] = {
593 {
594 .name = "s3c2410-rtc",
595 .driver_data = TYPE_S3C2410,
596 }, {
597 .name = "s3c64xx-rtc",
598 .driver_data = TYPE_S3C64XX,
599 },
600 { }
601 };
602
603 MODULE_DEVICE_TABLE(platform, s3c_rtc_driver_ids);
604
605 static struct platform_driver s3c_rtc_driver = {
606 .probe = s3c_rtc_probe,
607 .remove = __devexit_p(s3c_rtc_remove),
608 .suspend = s3c_rtc_suspend,
609 .resume = s3c_rtc_resume,
610 .id_table = s3c_rtc_driver_ids,
611 .driver = {
612 .name = "s3c-rtc",
613 .owner = THIS_MODULE,
614 },
615 };
616
617 static char __initdata banner[] = "S3C24XX RTC, (c) 2004,2006 Simtec Electronics\n";
618
619 static int __init s3c_rtc_init(void)
620 {
621 printk(banner);
622 return platform_driver_register(&s3c_rtc_driver);
623 }
624
625 static void __exit s3c_rtc_exit(void)
626 {
627 platform_driver_unregister(&s3c_rtc_driver);
628 }
629
630 module_init(s3c_rtc_init);
631 module_exit(s3c_rtc_exit);
632
633 MODULE_DESCRIPTION("Samsung S3C RTC Driver");
634 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
635 MODULE_LICENSE("GPL");
636 MODULE_ALIAS("platform:s3c2410-rtc");
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree