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26
27
28#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
29
30#include <linux/kernel.h>
31#include <linux/module.h>
32#include <linux/init.h>
33#include <linux/interrupt.h>
34#include <linux/spinlock.h>
35#include <linux/platform_device.h>
36#include <linux/log2.h>
37#include <linux/pm.h>
38#include <linux/of.h>
39#include <linux/of_platform.h>
40#ifdef CONFIG_X86
41#include <asm/i8259.h>
42#include <asm/processor.h>
43#include <linux/dmi.h>
44#endif
45
46
47#include <linux/mc146818rtc.h>
48
49#ifdef CONFIG_ACPI
50
51
52
53
54
55
56
57
58static bool use_acpi_alarm;
59module_param(use_acpi_alarm, bool, 0444);
60
61static inline int cmos_use_acpi_alarm(void)
62{
63 return use_acpi_alarm;
64}
65#else
66
67static inline int cmos_use_acpi_alarm(void)
68{
69 return 0;
70}
71#endif
72
73struct cmos_rtc {
74 struct rtc_device *rtc;
75 struct device *dev;
76 int irq;
77 struct resource *iomem;
78 time64_t alarm_expires;
79
80 void (*wake_on)(struct device *);
81 void (*wake_off)(struct device *);
82
83 u8 enabled_wake;
84 u8 suspend_ctrl;
85
86
87 u8 day_alrm;
88 u8 mon_alrm;
89 u8 century;
90
91 struct rtc_wkalrm saved_wkalrm;
92};
93
94
95#define is_valid_irq(n) ((n) > 0)
96
97static const char driver_name[] = "rtc_cmos";
98
99
100
101
102
103#define RTC_IRQMASK (RTC_PF | RTC_AF | RTC_UF)
104
105static inline int is_intr(u8 rtc_intr)
106{
107 if (!(rtc_intr & RTC_IRQF))
108 return 0;
109 return rtc_intr & RTC_IRQMASK;
110}
111
112
113
114
115
116
117
118
119
120
121
122
123
124#ifdef CONFIG_HPET_EMULATE_RTC
125#include <asm/hpet.h>
126#else
127
128static inline int is_hpet_enabled(void)
129{
130 return 0;
131}
132
133static inline int hpet_mask_rtc_irq_bit(unsigned long mask)
134{
135 return 0;
136}
137
138static inline int hpet_set_rtc_irq_bit(unsigned long mask)
139{
140 return 0;
141}
142
143static inline int
144hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned char sec)
145{
146 return 0;
147}
148
149static inline int hpet_set_periodic_freq(unsigned long freq)
150{
151 return 0;
152}
153
154static inline int hpet_rtc_dropped_irq(void)
155{
156 return 0;
157}
158
159static inline int hpet_rtc_timer_init(void)
160{
161 return 0;
162}
163
164extern irq_handler_t hpet_rtc_interrupt;
165
166static inline int hpet_register_irq_handler(irq_handler_t handler)
167{
168 return 0;
169}
170
171static inline int hpet_unregister_irq_handler(irq_handler_t handler)
172{
173 return 0;
174}
175
176#endif
177
178
179static inline int use_hpet_alarm(void)
180{
181 return is_hpet_enabled() && !cmos_use_acpi_alarm();
182}
183
184
185
186#ifdef RTC_PORT
187
188
189
190
191
192#define can_bank2 true
193
194static inline unsigned char cmos_read_bank2(unsigned char addr)
195{
196 outb(addr, RTC_PORT(2));
197 return inb(RTC_PORT(3));
198}
199
200static inline void cmos_write_bank2(unsigned char val, unsigned char addr)
201{
202 outb(addr, RTC_PORT(2));
203 outb(val, RTC_PORT(3));
204}
205
206#else
207
208#define can_bank2 false
209
210static inline unsigned char cmos_read_bank2(unsigned char addr)
211{
212 return 0;
213}
214
215static inline void cmos_write_bank2(unsigned char val, unsigned char addr)
216{
217}
218
219#endif
220
221
222
223static int cmos_read_time(struct device *dev, struct rtc_time *t)
224{
225
226
227
228
229 if (!pm_trace_rtc_valid())
230 return -EIO;
231
232
233
234
235
236 mc146818_get_time(t);
237 return 0;
238}
239
240static int cmos_set_time(struct device *dev, struct rtc_time *t)
241{
242
243
244
245
246
247
248 return mc146818_set_time(t);
249}
250
251static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
252{
253 struct cmos_rtc *cmos = dev_get_drvdata(dev);
254 unsigned char rtc_control;
255
256
257 if (!is_valid_irq(cmos->irq))
258 return -EIO;
259
260
261
262
263
264
265 spin_lock_irq(&rtc_lock);
266 t->time.tm_sec = CMOS_READ(RTC_SECONDS_ALARM);
267 t->time.tm_min = CMOS_READ(RTC_MINUTES_ALARM);
268 t->time.tm_hour = CMOS_READ(RTC_HOURS_ALARM);
269
270 if (cmos->day_alrm) {
271
272 t->time.tm_mday = CMOS_READ(cmos->day_alrm) & 0x3f;
273 if (!t->time.tm_mday)
274 t->time.tm_mday = -1;
275
276 if (cmos->mon_alrm) {
277 t->time.tm_mon = CMOS_READ(cmos->mon_alrm);
278 if (!t->time.tm_mon)
279 t->time.tm_mon = -1;
280 }
281 }
282
283 rtc_control = CMOS_READ(RTC_CONTROL);
284 spin_unlock_irq(&rtc_lock);
285
286 if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
287 if (((unsigned)t->time.tm_sec) < 0x60)
288 t->time.tm_sec = bcd2bin(t->time.tm_sec);
289 else
290 t->time.tm_sec = -1;
291 if (((unsigned)t->time.tm_min) < 0x60)
292 t->time.tm_min = bcd2bin(t->time.tm_min);
293 else
294 t->time.tm_min = -1;
295 if (((unsigned)t->time.tm_hour) < 0x24)
296 t->time.tm_hour = bcd2bin(t->time.tm_hour);
297 else
298 t->time.tm_hour = -1;
299
300 if (cmos->day_alrm) {
301 if (((unsigned)t->time.tm_mday) <= 0x31)
302 t->time.tm_mday = bcd2bin(t->time.tm_mday);
303 else
304 t->time.tm_mday = -1;
305
306 if (cmos->mon_alrm) {
307 if (((unsigned)t->time.tm_mon) <= 0x12)
308 t->time.tm_mon = bcd2bin(t->time.tm_mon)-1;
309 else
310 t->time.tm_mon = -1;
311 }
312 }
313 }
314
315 t->enabled = !!(rtc_control & RTC_AIE);
316 t->pending = 0;
317
318 return 0;
319}
320
321static void cmos_checkintr(struct cmos_rtc *cmos, unsigned char rtc_control)
322{
323 unsigned char rtc_intr;
324
325
326
327
328 rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
329
330 if (use_hpet_alarm())
331 return;
332
333 rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
334 if (is_intr(rtc_intr))
335 rtc_update_irq(cmos->rtc, 1, rtc_intr);
336}
337
338static void cmos_irq_enable(struct cmos_rtc *cmos, unsigned char mask)
339{
340 unsigned char rtc_control;
341
342
343
344
345 rtc_control = CMOS_READ(RTC_CONTROL);
346 cmos_checkintr(cmos, rtc_control);
347
348 rtc_control |= mask;
349 CMOS_WRITE(rtc_control, RTC_CONTROL);
350 if (use_hpet_alarm())
351 hpet_set_rtc_irq_bit(mask);
352
353 if ((mask & RTC_AIE) && cmos_use_acpi_alarm()) {
354 if (cmos->wake_on)
355 cmos->wake_on(cmos->dev);
356 }
357
358 cmos_checkintr(cmos, rtc_control);
359}
360
361static void cmos_irq_disable(struct cmos_rtc *cmos, unsigned char mask)
362{
363 unsigned char rtc_control;
364
365 rtc_control = CMOS_READ(RTC_CONTROL);
366 rtc_control &= ~mask;
367 CMOS_WRITE(rtc_control, RTC_CONTROL);
368 if (use_hpet_alarm())
369 hpet_mask_rtc_irq_bit(mask);
370
371 if ((mask & RTC_AIE) && cmos_use_acpi_alarm()) {
372 if (cmos->wake_off)
373 cmos->wake_off(cmos->dev);
374 }
375
376 cmos_checkintr(cmos, rtc_control);
377}
378
379static int cmos_validate_alarm(struct device *dev, struct rtc_wkalrm *t)
380{
381 struct cmos_rtc *cmos = dev_get_drvdata(dev);
382 struct rtc_time now;
383
384 cmos_read_time(dev, &now);
385
386 if (!cmos->day_alrm) {
387 time64_t t_max_date;
388 time64_t t_alrm;
389
390 t_max_date = rtc_tm_to_time64(&now);
391 t_max_date += 24 * 60 * 60 - 1;
392 t_alrm = rtc_tm_to_time64(&t->time);
393 if (t_alrm > t_max_date) {
394 dev_err(dev,
395 "Alarms can be up to one day in the future\n");
396 return -EINVAL;
397 }
398 } else if (!cmos->mon_alrm) {
399 struct rtc_time max_date = now;
400 time64_t t_max_date;
401 time64_t t_alrm;
402 int max_mday;
403
404 if (max_date.tm_mon == 11) {
405 max_date.tm_mon = 0;
406 max_date.tm_year += 1;
407 } else {
408 max_date.tm_mon += 1;
409 }
410 max_mday = rtc_month_days(max_date.tm_mon, max_date.tm_year);
411 if (max_date.tm_mday > max_mday)
412 max_date.tm_mday = max_mday;
413
414 t_max_date = rtc_tm_to_time64(&max_date);
415 t_max_date -= 1;
416 t_alrm = rtc_tm_to_time64(&t->time);
417 if (t_alrm > t_max_date) {
418 dev_err(dev,
419 "Alarms can be up to one month in the future\n");
420 return -EINVAL;
421 }
422 } else {
423 struct rtc_time max_date = now;
424 time64_t t_max_date;
425 time64_t t_alrm;
426 int max_mday;
427
428 max_date.tm_year += 1;
429 max_mday = rtc_month_days(max_date.tm_mon, max_date.tm_year);
430 if (max_date.tm_mday > max_mday)
431 max_date.tm_mday = max_mday;
432
433 t_max_date = rtc_tm_to_time64(&max_date);
434 t_max_date -= 1;
435 t_alrm = rtc_tm_to_time64(&t->time);
436 if (t_alrm > t_max_date) {
437 dev_err(dev,
438 "Alarms can be up to one year in the future\n");
439 return -EINVAL;
440 }
441 }
442
443 return 0;
444}
445
446static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
447{
448 struct cmos_rtc *cmos = dev_get_drvdata(dev);
449 unsigned char mon, mday, hrs, min, sec, rtc_control;
450 int ret;
451
452
453 if (!is_valid_irq(cmos->irq))
454 return -EIO;
455
456 ret = cmos_validate_alarm(dev, t);
457 if (ret < 0)
458 return ret;
459
460 mon = t->time.tm_mon + 1;
461 mday = t->time.tm_mday;
462 hrs = t->time.tm_hour;
463 min = t->time.tm_min;
464 sec = t->time.tm_sec;
465
466 rtc_control = CMOS_READ(RTC_CONTROL);
467 if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
468
469 mon = (mon <= 12) ? bin2bcd(mon) : 0xff;
470 mday = (mday >= 1 && mday <= 31) ? bin2bcd(mday) : 0xff;
471 hrs = (hrs < 24) ? bin2bcd(hrs) : 0xff;
472 min = (min < 60) ? bin2bcd(min) : 0xff;
473 sec = (sec < 60) ? bin2bcd(sec) : 0xff;
474 }
475
476 spin_lock_irq(&rtc_lock);
477
478
479 cmos_irq_disable(cmos, RTC_AIE);
480
481
482 CMOS_WRITE(hrs, RTC_HOURS_ALARM);
483 CMOS_WRITE(min, RTC_MINUTES_ALARM);
484 CMOS_WRITE(sec, RTC_SECONDS_ALARM);
485
486
487 if (cmos->day_alrm) {
488 CMOS_WRITE(mday, cmos->day_alrm);
489 if (cmos->mon_alrm)
490 CMOS_WRITE(mon, cmos->mon_alrm);
491 }
492
493 if (use_hpet_alarm()) {
494
495
496
497
498 hpet_set_alarm_time(t->time.tm_hour, t->time.tm_min,
499 t->time.tm_sec);
500 }
501
502 if (t->enabled)
503 cmos_irq_enable(cmos, RTC_AIE);
504
505 spin_unlock_irq(&rtc_lock);
506
507 cmos->alarm_expires = rtc_tm_to_time64(&t->time);
508
509 return 0;
510}
511
512static int cmos_alarm_irq_enable(struct device *dev, unsigned int enabled)
513{
514 struct cmos_rtc *cmos = dev_get_drvdata(dev);
515 unsigned long flags;
516
517 spin_lock_irqsave(&rtc_lock, flags);
518
519 if (enabled)
520 cmos_irq_enable(cmos, RTC_AIE);
521 else
522 cmos_irq_disable(cmos, RTC_AIE);
523
524 spin_unlock_irqrestore(&rtc_lock, flags);
525 return 0;
526}
527
528#if IS_ENABLED(CONFIG_RTC_INTF_PROC)
529
530static int cmos_procfs(struct device *dev, struct seq_file *seq)
531{
532 struct cmos_rtc *cmos = dev_get_drvdata(dev);
533 unsigned char rtc_control, valid;
534
535 spin_lock_irq(&rtc_lock);
536 rtc_control = CMOS_READ(RTC_CONTROL);
537 valid = CMOS_READ(RTC_VALID);
538 spin_unlock_irq(&rtc_lock);
539
540
541
542
543 seq_printf(seq,
544 "periodic_IRQ\t: %s\n"
545 "update_IRQ\t: %s\n"
546 "HPET_emulated\t: %s\n"
547
548 "BCD\t\t: %s\n"
549 "DST_enable\t: %s\n"
550 "periodic_freq\t: %d\n"
551 "batt_status\t: %s\n",
552 (rtc_control & RTC_PIE) ? "yes" : "no",
553 (rtc_control & RTC_UIE) ? "yes" : "no",
554 use_hpet_alarm() ? "yes" : "no",
555
556 (rtc_control & RTC_DM_BINARY) ? "no" : "yes",
557 (rtc_control & RTC_DST_EN) ? "yes" : "no",
558 cmos->rtc->irq_freq,
559 (valid & RTC_VRT) ? "okay" : "dead");
560
561 return 0;
562}
563
564#else
565#define cmos_procfs NULL
566#endif
567
568static const struct rtc_class_ops cmos_rtc_ops = {
569 .read_time = cmos_read_time,
570 .set_time = cmos_set_time,
571 .read_alarm = cmos_read_alarm,
572 .set_alarm = cmos_set_alarm,
573 .proc = cmos_procfs,
574 .alarm_irq_enable = cmos_alarm_irq_enable,
575};
576
577
578
579
580
581
582
583
584
585#define NVRAM_OFFSET (RTC_REG_D + 1)
586
587static int cmos_nvram_read(void *priv, unsigned int off, void *val,
588 size_t count)
589{
590 unsigned char *buf = val;
591 int retval;
592
593 off += NVRAM_OFFSET;
594 spin_lock_irq(&rtc_lock);
595 for (retval = 0; count; count--, off++, retval++) {
596 if (off < 128)
597 *buf++ = CMOS_READ(off);
598 else if (can_bank2)
599 *buf++ = cmos_read_bank2(off);
600 else
601 break;
602 }
603 spin_unlock_irq(&rtc_lock);
604
605 return retval;
606}
607
608static int cmos_nvram_write(void *priv, unsigned int off, void *val,
609 size_t count)
610{
611 struct cmos_rtc *cmos = priv;
612 unsigned char *buf = val;
613 int retval;
614
615
616
617
618
619
620 off += NVRAM_OFFSET;
621 spin_lock_irq(&rtc_lock);
622 for (retval = 0; count; count--, off++, retval++) {
623
624 if (off == cmos->day_alrm
625 || off == cmos->mon_alrm
626 || off == cmos->century)
627 buf++;
628 else if (off < 128)
629 CMOS_WRITE(*buf++, off);
630 else if (can_bank2)
631 cmos_write_bank2(*buf++, off);
632 else
633 break;
634 }
635 spin_unlock_irq(&rtc_lock);
636
637 return retval;
638}
639
640
641
642static struct cmos_rtc cmos_rtc;
643
644static irqreturn_t cmos_interrupt(int irq, void *p)
645{
646 u8 irqstat;
647 u8 rtc_control;
648
649 spin_lock(&rtc_lock);
650
651
652
653
654
655
656
657
658 irqstat = CMOS_READ(RTC_INTR_FLAGS);
659 rtc_control = CMOS_READ(RTC_CONTROL);
660 if (use_hpet_alarm())
661 irqstat = (unsigned long)irq & 0xF0;
662
663
664
665
666 if (!cmos_rtc.suspend_ctrl)
667 irqstat &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
668 else
669 irqstat &= (cmos_rtc.suspend_ctrl & RTC_IRQMASK) | RTC_IRQF;
670
671
672
673
674
675 if (irqstat & RTC_AIE) {
676 cmos_rtc.suspend_ctrl &= ~RTC_AIE;
677 rtc_control &= ~RTC_AIE;
678 CMOS_WRITE(rtc_control, RTC_CONTROL);
679 if (use_hpet_alarm())
680 hpet_mask_rtc_irq_bit(RTC_AIE);
681 CMOS_READ(RTC_INTR_FLAGS);
682 }
683 spin_unlock(&rtc_lock);
684
685 if (is_intr(irqstat)) {
686 rtc_update_irq(p, 1, irqstat);
687 return IRQ_HANDLED;
688 } else
689 return IRQ_NONE;
690}
691
692#ifdef CONFIG_PNP
693#define INITSECTION
694
695#else
696#define INITSECTION __init
697#endif
698
699static int INITSECTION
700cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
701{
702 struct cmos_rtc_board_info *info = dev_get_platdata(dev);
703 int retval = 0;
704 unsigned char rtc_control;
705 unsigned address_space;
706 u32 flags = 0;
707 struct nvmem_config nvmem_cfg = {
708 .name = "cmos_nvram",
709 .word_size = 1,
710 .stride = 1,
711 .reg_read = cmos_nvram_read,
712 .reg_write = cmos_nvram_write,
713 .priv = &cmos_rtc,
714 };
715
716
717 if (cmos_rtc.dev)
718 return -EBUSY;
719
720 if (!ports)
721 return -ENODEV;
722
723
724
725
726
727
728 if (RTC_IOMAPPED)
729 ports = request_region(ports->start, resource_size(ports),
730 driver_name);
731 else
732 ports = request_mem_region(ports->start, resource_size(ports),
733 driver_name);
734 if (!ports) {
735 dev_dbg(dev, "i/o registers already in use\n");
736 return -EBUSY;
737 }
738
739 cmos_rtc.irq = rtc_irq;
740 cmos_rtc.iomem = ports;
741
742
743
744
745
746
747#if defined(CONFIG_ATARI)
748 address_space = 64;
749#elif defined(__i386__) || defined(__x86_64__) || defined(__arm__) \
750 || defined(__sparc__) || defined(__mips__) \
751 || defined(__powerpc__)
752 address_space = 128;
753#else
754#warning Assuming 128 bytes of RTC+NVRAM address space, not 64 bytes.
755 address_space = 128;
756#endif
757 if (can_bank2 && ports->end > (ports->start + 1))
758 address_space = 256;
759
760
761
762
763
764
765
766
767
768
769 if (info) {
770 if (info->flags)
771 flags = info->flags;
772 if (info->address_space)
773 address_space = info->address_space;
774
775 if (info->rtc_day_alarm && info->rtc_day_alarm < 128)
776 cmos_rtc.day_alrm = info->rtc_day_alarm;
777 if (info->rtc_mon_alarm && info->rtc_mon_alarm < 128)
778 cmos_rtc.mon_alrm = info->rtc_mon_alarm;
779 if (info->rtc_century && info->rtc_century < 128)
780 cmos_rtc.century = info->rtc_century;
781
782 if (info->wake_on && info->wake_off) {
783 cmos_rtc.wake_on = info->wake_on;
784 cmos_rtc.wake_off = info->wake_off;
785 }
786 }
787
788 cmos_rtc.dev = dev;
789 dev_set_drvdata(dev, &cmos_rtc);
790
791 cmos_rtc.rtc = devm_rtc_allocate_device(dev);
792 if (IS_ERR(cmos_rtc.rtc)) {
793 retval = PTR_ERR(cmos_rtc.rtc);
794 goto cleanup0;
795 }
796
797 rename_region(ports, dev_name(&cmos_rtc.rtc->dev));
798
799 spin_lock_irq(&rtc_lock);
800
801
802 if ((CMOS_READ(RTC_VALID) & 0x40) != 0) {
803 spin_unlock_irq(&rtc_lock);
804 dev_warn(dev, "not accessible\n");
805 retval = -ENXIO;
806 goto cleanup1;
807 }
808
809 if (!(flags & CMOS_RTC_FLAGS_NOFREQ)) {
810
811
812
813
814
815
816 cmos_rtc.rtc->irq_freq = 1024;
817 if (use_hpet_alarm())
818 hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq);
819 CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
820 }
821
822
823 if (is_valid_irq(rtc_irq))
824 cmos_irq_disable(&cmos_rtc, RTC_PIE | RTC_AIE | RTC_UIE);
825
826 rtc_control = CMOS_READ(RTC_CONTROL);
827
828 spin_unlock_irq(&rtc_lock);
829
830 if (is_valid_irq(rtc_irq) && !(rtc_control & RTC_24H)) {
831 dev_warn(dev, "only 24-hr supported\n");
832 retval = -ENXIO;
833 goto cleanup1;
834 }
835
836 if (use_hpet_alarm())
837 hpet_rtc_timer_init();
838
839 if (is_valid_irq(rtc_irq)) {
840 irq_handler_t rtc_cmos_int_handler;
841
842 if (use_hpet_alarm()) {
843 rtc_cmos_int_handler = hpet_rtc_interrupt;
844 retval = hpet_register_irq_handler(cmos_interrupt);
845 if (retval) {
846 hpet_mask_rtc_irq_bit(RTC_IRQMASK);
847 dev_warn(dev, "hpet_register_irq_handler "
848 " failed in rtc_init().");
849 goto cleanup1;
850 }
851 } else
852 rtc_cmos_int_handler = cmos_interrupt;
853
854 retval = request_irq(rtc_irq, rtc_cmos_int_handler,
855 0, dev_name(&cmos_rtc.rtc->dev),
856 cmos_rtc.rtc);
857 if (retval < 0) {
858 dev_dbg(dev, "IRQ %d is already in use\n", rtc_irq);
859 goto cleanup1;
860 }
861 } else {
862 clear_bit(RTC_FEATURE_ALARM, cmos_rtc.rtc->features);
863 }
864
865 cmos_rtc.rtc->ops = &cmos_rtc_ops;
866
867 retval = devm_rtc_register_device(cmos_rtc.rtc);
868 if (retval)
869 goto cleanup2;
870
871
872 cmos_rtc.rtc->set_offset_nsec = NSEC_PER_SEC / 2;
873
874
875 nvmem_cfg.size = address_space - NVRAM_OFFSET;
876 devm_rtc_nvmem_register(cmos_rtc.rtc, &nvmem_cfg);
877
878 dev_info(dev, "%s%s, %d bytes nvram%s\n",
879 !is_valid_irq(rtc_irq) ? "no alarms" :
880 cmos_rtc.mon_alrm ? "alarms up to one year" :
881 cmos_rtc.day_alrm ? "alarms up to one month" :
882 "alarms up to one day",
883 cmos_rtc.century ? ", y3k" : "",
884 nvmem_cfg.size,
885 use_hpet_alarm() ? ", hpet irqs" : "");
886
887 return 0;
888
889cleanup2:
890 if (is_valid_irq(rtc_irq))
891 free_irq(rtc_irq, cmos_rtc.rtc);
892cleanup1:
893 cmos_rtc.dev = NULL;
894cleanup0:
895 if (RTC_IOMAPPED)
896 release_region(ports->start, resource_size(ports));
897 else
898 release_mem_region(ports->start, resource_size(ports));
899 return retval;
900}
901
902static void cmos_do_shutdown(int rtc_irq)
903{
904 spin_lock_irq(&rtc_lock);
905 if (is_valid_irq(rtc_irq))
906 cmos_irq_disable(&cmos_rtc, RTC_IRQMASK);
907 spin_unlock_irq(&rtc_lock);
908}
909
910static void cmos_do_remove(struct device *dev)
911{
912 struct cmos_rtc *cmos = dev_get_drvdata(dev);
913 struct resource *ports;
914
915 cmos_do_shutdown(cmos->irq);
916
917 if (is_valid_irq(cmos->irq)) {
918 free_irq(cmos->irq, cmos->rtc);
919 if (use_hpet_alarm())
920 hpet_unregister_irq_handler(cmos_interrupt);
921 }
922
923 cmos->rtc = NULL;
924
925 ports = cmos->iomem;
926 if (RTC_IOMAPPED)
927 release_region(ports->start, resource_size(ports));
928 else
929 release_mem_region(ports->start, resource_size(ports));
930 cmos->iomem = NULL;
931
932 cmos->dev = NULL;
933}
934
935static int cmos_aie_poweroff(struct device *dev)
936{
937 struct cmos_rtc *cmos = dev_get_drvdata(dev);
938 struct rtc_time now;
939 time64_t t_now;
940 int retval = 0;
941 unsigned char rtc_control;
942
943 if (!cmos->alarm_expires)
944 return -EINVAL;
945
946 spin_lock_irq(&rtc_lock);
947 rtc_control = CMOS_READ(RTC_CONTROL);
948 spin_unlock_irq(&rtc_lock);
949
950
951 if (rtc_control & RTC_AIE)
952 return -EBUSY;
953
954 cmos_read_time(dev, &now);
955 t_now = rtc_tm_to_time64(&now);
956
957
958
959
960
961
962
963
964
965
966 if (cmos->alarm_expires == t_now + 1) {
967 struct rtc_wkalrm alarm;
968
969
970 rtc_time64_to_tm(t_now - 1, &alarm.time);
971 alarm.enabled = 0;
972 retval = cmos_set_alarm(dev, &alarm);
973 } else if (cmos->alarm_expires > t_now + 1) {
974 retval = -EBUSY;
975 }
976
977 return retval;
978}
979
980static int cmos_suspend(struct device *dev)
981{
982 struct cmos_rtc *cmos = dev_get_drvdata(dev);
983 unsigned char tmp;
984
985
986 spin_lock_irq(&rtc_lock);
987 cmos->suspend_ctrl = tmp = CMOS_READ(RTC_CONTROL);
988 if (tmp & (RTC_PIE|RTC_AIE|RTC_UIE)) {
989 unsigned char mask;
990
991 if (device_may_wakeup(dev))
992 mask = RTC_IRQMASK & ~RTC_AIE;
993 else
994 mask = RTC_IRQMASK;
995 tmp &= ~mask;
996 CMOS_WRITE(tmp, RTC_CONTROL);
997 if (use_hpet_alarm())
998 hpet_mask_rtc_irq_bit(mask);
999 cmos_checkintr(cmos, tmp);
1000 }
1001 spin_unlock_irq(&rtc_lock);
1002
1003 if ((tmp & RTC_AIE) && !cmos_use_acpi_alarm()) {
1004 cmos->enabled_wake = 1;
1005 if (cmos->wake_on)
1006 cmos->wake_on(dev);
1007 else
1008 enable_irq_wake(cmos->irq);
1009 }
1010
1011 memset(&cmos->saved_wkalrm, 0, sizeof(struct rtc_wkalrm));
1012 cmos_read_alarm(dev, &cmos->saved_wkalrm);
1013
1014 dev_dbg(dev, "suspend%s, ctrl %02x\n",
1015 (tmp & RTC_AIE) ? ", alarm may wake" : "",
1016 tmp);
1017
1018 return 0;
1019}
1020
1021
1022
1023
1024
1025
1026
1027static inline int cmos_poweroff(struct device *dev)
1028{
1029 if (!IS_ENABLED(CONFIG_PM))
1030 return -ENOSYS;
1031
1032 return cmos_suspend(dev);
1033}
1034
1035static void cmos_check_wkalrm(struct device *dev)
1036{
1037 struct cmos_rtc *cmos = dev_get_drvdata(dev);
1038 struct rtc_wkalrm current_alarm;
1039 time64_t t_now;
1040 time64_t t_current_expires;
1041 time64_t t_saved_expires;
1042 struct rtc_time now;
1043
1044
1045 if (!(cmos->suspend_ctrl & RTC_AIE))
1046 return;
1047
1048 cmos_read_time(dev, &now);
1049 t_now = rtc_tm_to_time64(&now);
1050
1051
1052
1053
1054
1055 if (t_now >= cmos->alarm_expires && cmos_use_acpi_alarm()) {
1056 cmos_interrupt(0, (void *)cmos->rtc);
1057 return;
1058 }
1059
1060 memset(¤t_alarm, 0, sizeof(struct rtc_wkalrm));
1061 cmos_read_alarm(dev, ¤t_alarm);
1062 t_current_expires = rtc_tm_to_time64(¤t_alarm.time);
1063 t_saved_expires = rtc_tm_to_time64(&cmos->saved_wkalrm.time);
1064 if (t_current_expires != t_saved_expires ||
1065 cmos->saved_wkalrm.enabled != current_alarm.enabled) {
1066 cmos_set_alarm(dev, &cmos->saved_wkalrm);
1067 }
1068}
1069
1070static void cmos_check_acpi_rtc_status(struct device *dev,
1071 unsigned char *rtc_control);
1072
1073static int __maybe_unused cmos_resume(struct device *dev)
1074{
1075 struct cmos_rtc *cmos = dev_get_drvdata(dev);
1076 unsigned char tmp;
1077
1078 if (cmos->enabled_wake && !cmos_use_acpi_alarm()) {
1079 if (cmos->wake_off)
1080 cmos->wake_off(dev);
1081 else
1082 disable_irq_wake(cmos->irq);
1083 cmos->enabled_wake = 0;
1084 }
1085
1086
1087 cmos_check_wkalrm(dev);
1088
1089 spin_lock_irq(&rtc_lock);
1090 tmp = cmos->suspend_ctrl;
1091 cmos->suspend_ctrl = 0;
1092
1093 if (tmp & RTC_IRQMASK) {
1094 unsigned char mask;
1095
1096 if (device_may_wakeup(dev) && use_hpet_alarm())
1097 hpet_rtc_timer_init();
1098
1099 do {
1100 CMOS_WRITE(tmp, RTC_CONTROL);
1101 if (use_hpet_alarm())
1102 hpet_set_rtc_irq_bit(tmp & RTC_IRQMASK);
1103
1104 mask = CMOS_READ(RTC_INTR_FLAGS);
1105 mask &= (tmp & RTC_IRQMASK) | RTC_IRQF;
1106 if (!use_hpet_alarm() || !is_intr(mask))
1107 break;
1108
1109
1110
1111
1112 rtc_update_irq(cmos->rtc, 1, mask);
1113 tmp &= ~RTC_AIE;
1114 hpet_mask_rtc_irq_bit(RTC_AIE);
1115 } while (mask & RTC_AIE);
1116
1117 if (tmp & RTC_AIE)
1118 cmos_check_acpi_rtc_status(dev, &tmp);
1119 }
1120 spin_unlock_irq(&rtc_lock);
1121
1122 dev_dbg(dev, "resume, ctrl %02x\n", tmp);
1123
1124 return 0;
1125}
1126
1127static SIMPLE_DEV_PM_OPS(cmos_pm_ops, cmos_suspend, cmos_resume);
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139#ifdef CONFIG_ACPI
1140
1141#include <linux/acpi.h>
1142
1143static u32 rtc_handler(void *context)
1144{
1145 struct device *dev = context;
1146 struct cmos_rtc *cmos = dev_get_drvdata(dev);
1147 unsigned char rtc_control = 0;
1148 unsigned char rtc_intr;
1149 unsigned long flags;
1150
1151
1152
1153
1154
1155
1156
1157 if (cmos_use_acpi_alarm())
1158 cmos_interrupt(0, (void *)cmos->rtc);
1159 else {
1160
1161 spin_lock_irqsave(&rtc_lock, flags);
1162 if (cmos_rtc.suspend_ctrl)
1163 rtc_control = CMOS_READ(RTC_CONTROL);
1164 if (rtc_control & RTC_AIE) {
1165 cmos_rtc.suspend_ctrl &= ~RTC_AIE;
1166 CMOS_WRITE(rtc_control, RTC_CONTROL);
1167 rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
1168 rtc_update_irq(cmos->rtc, 1, rtc_intr);
1169 }
1170 spin_unlock_irqrestore(&rtc_lock, flags);
1171 }
1172
1173 pm_wakeup_hard_event(dev);
1174 acpi_clear_event(ACPI_EVENT_RTC);
1175 acpi_disable_event(ACPI_EVENT_RTC, 0);
1176 return ACPI_INTERRUPT_HANDLED;
1177}
1178
1179static inline void rtc_wake_setup(struct device *dev)
1180{
1181 acpi_install_fixed_event_handler(ACPI_EVENT_RTC, rtc_handler, dev);
1182
1183
1184
1185
1186 acpi_clear_event(ACPI_EVENT_RTC);
1187 acpi_disable_event(ACPI_EVENT_RTC, 0);
1188}
1189
1190static void rtc_wake_on(struct device *dev)
1191{
1192 acpi_clear_event(ACPI_EVENT_RTC);
1193 acpi_enable_event(ACPI_EVENT_RTC, 0);
1194}
1195
1196static void rtc_wake_off(struct device *dev)
1197{
1198 acpi_disable_event(ACPI_EVENT_RTC, 0);
1199}
1200
1201#ifdef CONFIG_X86
1202
1203static void use_acpi_alarm_quirks(void)
1204{
1205 if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
1206 return;
1207
1208 if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
1209 return;
1210
1211 if (!is_hpet_enabled())
1212 return;
1213
1214 if (dmi_get_bios_year() < 2015)
1215 return;
1216
1217 use_acpi_alarm = true;
1218}
1219#else
1220static inline void use_acpi_alarm_quirks(void) { }
1221#endif
1222
1223
1224
1225
1226
1227
1228static struct cmos_rtc_board_info acpi_rtc_info;
1229
1230static void cmos_wake_setup(struct device *dev)
1231{
1232 if (acpi_disabled)
1233 return;
1234
1235 use_acpi_alarm_quirks();
1236
1237 rtc_wake_setup(dev);
1238 acpi_rtc_info.wake_on = rtc_wake_on;
1239 acpi_rtc_info.wake_off = rtc_wake_off;
1240
1241
1242 if (acpi_gbl_FADT.month_alarm && !acpi_gbl_FADT.day_alarm) {
1243 dev_dbg(dev, "bogus FADT month_alarm (%d)\n",
1244 acpi_gbl_FADT.month_alarm);
1245 acpi_gbl_FADT.month_alarm = 0;
1246 }
1247
1248 acpi_rtc_info.rtc_day_alarm = acpi_gbl_FADT.day_alarm;
1249 acpi_rtc_info.rtc_mon_alarm = acpi_gbl_FADT.month_alarm;
1250 acpi_rtc_info.rtc_century = acpi_gbl_FADT.century;
1251
1252
1253 if (acpi_gbl_FADT.flags & ACPI_FADT_S4_RTC_WAKE)
1254 dev_info(dev, "RTC can wake from S4\n");
1255
1256 dev->platform_data = &acpi_rtc_info;
1257
1258
1259 device_init_wakeup(dev, 1);
1260}
1261
1262static void cmos_check_acpi_rtc_status(struct device *dev,
1263 unsigned char *rtc_control)
1264{
1265 struct cmos_rtc *cmos = dev_get_drvdata(dev);
1266 acpi_event_status rtc_status;
1267 acpi_status status;
1268
1269 if (acpi_gbl_FADT.flags & ACPI_FADT_FIXED_RTC)
1270 return;
1271
1272 status = acpi_get_event_status(ACPI_EVENT_RTC, &rtc_status);
1273 if (ACPI_FAILURE(status)) {
1274 dev_err(dev, "Could not get RTC status\n");
1275 } else if (rtc_status & ACPI_EVENT_FLAG_SET) {
1276 unsigned char mask;
1277 *rtc_control &= ~RTC_AIE;
1278 CMOS_WRITE(*rtc_control, RTC_CONTROL);
1279 mask = CMOS_READ(RTC_INTR_FLAGS);
1280 rtc_update_irq(cmos->rtc, 1, mask);
1281 }
1282}
1283
1284#else
1285
1286static void cmos_wake_setup(struct device *dev)
1287{
1288}
1289
1290static void cmos_check_acpi_rtc_status(struct device *dev,
1291 unsigned char *rtc_control)
1292{
1293}
1294
1295#endif
1296
1297#ifdef CONFIG_PNP
1298
1299#include <linux/pnp.h>
1300
1301static int cmos_pnp_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
1302{
1303 cmos_wake_setup(&pnp->dev);
1304
1305 if (pnp_port_start(pnp, 0) == 0x70 && !pnp_irq_valid(pnp, 0)) {
1306 unsigned int irq = 0;
1307#ifdef CONFIG_X86
1308
1309
1310
1311
1312 if (nr_legacy_irqs())
1313 irq = RTC_IRQ;
1314#endif
1315 return cmos_do_probe(&pnp->dev,
1316 pnp_get_resource(pnp, IORESOURCE_IO, 0), irq);
1317 } else {
1318 return cmos_do_probe(&pnp->dev,
1319 pnp_get_resource(pnp, IORESOURCE_IO, 0),
1320 pnp_irq(pnp, 0));
1321 }
1322}
1323
1324static void cmos_pnp_remove(struct pnp_dev *pnp)
1325{
1326 cmos_do_remove(&pnp->dev);
1327}
1328
1329static void cmos_pnp_shutdown(struct pnp_dev *pnp)
1330{
1331 struct device *dev = &pnp->dev;
1332 struct cmos_rtc *cmos = dev_get_drvdata(dev);
1333
1334 if (system_state == SYSTEM_POWER_OFF) {
1335 int retval = cmos_poweroff(dev);
1336
1337 if (cmos_aie_poweroff(dev) < 0 && !retval)
1338 return;
1339 }
1340
1341 cmos_do_shutdown(cmos->irq);
1342}
1343
1344static const struct pnp_device_id rtc_ids[] = {
1345 { .id = "PNP0b00", },
1346 { .id = "PNP0b01", },
1347 { .id = "PNP0b02", },
1348 { },
1349};
1350MODULE_DEVICE_TABLE(pnp, rtc_ids);
1351
1352static struct pnp_driver cmos_pnp_driver = {
1353 .name = driver_name,
1354 .id_table = rtc_ids,
1355 .probe = cmos_pnp_probe,
1356 .remove = cmos_pnp_remove,
1357 .shutdown = cmos_pnp_shutdown,
1358
1359
1360 .flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
1361 .driver = {
1362 .pm = &cmos_pm_ops,
1363 },
1364};
1365
1366#endif
1367
1368#ifdef CONFIG_OF
1369static const struct of_device_id of_cmos_match[] = {
1370 {
1371 .compatible = "motorola,mc146818",
1372 },
1373 { },
1374};
1375MODULE_DEVICE_TABLE(of, of_cmos_match);
1376
1377static __init void cmos_of_init(struct platform_device *pdev)
1378{
1379 struct device_node *node = pdev->dev.of_node;
1380 const __be32 *val;
1381
1382 if (!node)
1383 return;
1384
1385 val = of_get_property(node, "ctrl-reg", NULL);
1386 if (val)
1387 CMOS_WRITE(be32_to_cpup(val), RTC_CONTROL);
1388
1389 val = of_get_property(node, "freq-reg", NULL);
1390 if (val)
1391 CMOS_WRITE(be32_to_cpup(val), RTC_FREQ_SELECT);
1392}
1393#else
1394static inline void cmos_of_init(struct platform_device *pdev) {}
1395#endif
1396
1397
1398
1399
1400
1401
1402static int __init cmos_platform_probe(struct platform_device *pdev)
1403{
1404 struct resource *resource;
1405 int irq;
1406
1407 cmos_of_init(pdev);
1408 cmos_wake_setup(&pdev->dev);
1409
1410 if (RTC_IOMAPPED)
1411 resource = platform_get_resource(pdev, IORESOURCE_IO, 0);
1412 else
1413 resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1414 irq = platform_get_irq(pdev, 0);
1415 if (irq < 0)
1416 irq = -1;
1417
1418 return cmos_do_probe(&pdev->dev, resource, irq);
1419}
1420
1421static int cmos_platform_remove(struct platform_device *pdev)
1422{
1423 cmos_do_remove(&pdev->dev);
1424 return 0;
1425}
1426
1427static void cmos_platform_shutdown(struct platform_device *pdev)
1428{
1429 struct device *dev = &pdev->dev;
1430 struct cmos_rtc *cmos = dev_get_drvdata(dev);
1431
1432 if (system_state == SYSTEM_POWER_OFF) {
1433 int retval = cmos_poweroff(dev);
1434
1435 if (cmos_aie_poweroff(dev) < 0 && !retval)
1436 return;
1437 }
1438
1439 cmos_do_shutdown(cmos->irq);
1440}
1441
1442
1443MODULE_ALIAS("platform:rtc_cmos");
1444
1445static struct platform_driver cmos_platform_driver = {
1446 .remove = cmos_platform_remove,
1447 .shutdown = cmos_platform_shutdown,
1448 .driver = {
1449 .name = driver_name,
1450 .pm = &cmos_pm_ops,
1451 .of_match_table = of_match_ptr(of_cmos_match),
1452 }
1453};
1454
1455#ifdef CONFIG_PNP
1456static bool pnp_driver_registered;
1457#endif
1458static bool platform_driver_registered;
1459
1460static int __init cmos_init(void)
1461{
1462 int retval = 0;
1463
1464#ifdef CONFIG_PNP
1465 retval = pnp_register_driver(&cmos_pnp_driver);
1466 if (retval == 0)
1467 pnp_driver_registered = true;
1468#endif
1469
1470 if (!cmos_rtc.dev) {
1471 retval = platform_driver_probe(&cmos_platform_driver,
1472 cmos_platform_probe);
1473 if (retval == 0)
1474 platform_driver_registered = true;
1475 }
1476
1477 if (retval == 0)
1478 return 0;
1479
1480#ifdef CONFIG_PNP
1481 if (pnp_driver_registered)
1482 pnp_unregister_driver(&cmos_pnp_driver);
1483#endif
1484 return retval;
1485}
1486module_init(cmos_init);
1487
1488static void __exit cmos_exit(void)
1489{
1490#ifdef CONFIG_PNP
1491 if (pnp_driver_registered)
1492 pnp_unregister_driver(&cmos_pnp_driver);
1493#endif
1494 if (platform_driver_registered)
1495 platform_driver_unregister(&cmos_platform_driver);
1496}
1497module_exit(cmos_exit);
1498
1499
1500MODULE_AUTHOR("David Brownell");
1501MODULE_DESCRIPTION("Driver for PC-style 'CMOS' RTCs");
1502MODULE_LICENSE("GPL");
1503