blob: 43745cac0141a4445dda3abe6a31d8ca172355b0 [file] [log] [blame]
David Brownell7be2c7c2007-02-10 01:46:02 -08001/*
2 * RTC class driver for "CMOS RTC": PCs, ACPI, etc
3 *
4 * Copyright (C) 1996 Paul Gortmaker (drivers/char/rtc.c)
5 * Copyright (C) 2006 David Brownell (convert to new framework)
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12
13/*
14 * The original "cmos clock" chip was an MC146818 chip, now obsolete.
15 * That defined the register interface now provided by all PCs, some
16 * non-PC systems, and incorporated into ACPI. Modern PC chipsets
17 * integrate an MC146818 clone in their southbridge, and boards use
18 * that instead of discrete clones like the DS12887 or M48T86. There
19 * are also clones that connect using the LPC bus.
20 *
21 * That register API is also used directly by various other drivers
22 * (notably for integrated NVRAM), infrastructure (x86 has code to
23 * bypass the RTC framework, directly reading the RTC during boot
24 * and updating minutes/seconds for systems using NTP synch) and
25 * utilities (like userspace 'hwclock', if no /dev node exists).
26 *
27 * So **ALL** calls to CMOS_READ and CMOS_WRITE must be done with
28 * interrupts disabled, holding the global rtc_lock, to exclude those
29 * other drivers and utilities on correctly configured systems.
30 */
Joe Perchesa737e832015-04-16 12:46:14 -070031
32#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
33
David Brownell7be2c7c2007-02-10 01:46:02 -080034#include <linux/kernel.h>
35#include <linux/module.h>
36#include <linux/init.h>
37#include <linux/interrupt.h>
38#include <linux/spinlock.h>
39#include <linux/platform_device.h>
Jonathan Cameron5d2a5032009-01-06 14:42:12 -080040#include <linux/log2.h>
Paul Fox2fb08e62011-01-12 17:00:07 -080041#include <linux/pm.h>
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +010042#include <linux/of.h>
43#include <linux/of_platform.h>
David Brownell7be2c7c2007-02-10 01:46:02 -080044
45/* this is for "generic access to PC-style RTC" using CMOS_READ/CMOS_WRITE */
Arnd Bergmann5ab788d2016-05-30 20:57:50 +020046#include <linux/mc146818rtc.h>
David Brownell7be2c7c2007-02-10 01:46:02 -080047
David Brownell7be2c7c2007-02-10 01:46:02 -080048struct cmos_rtc {
49 struct rtc_device *rtc;
50 struct device *dev;
51 int irq;
52 struct resource *iomem;
Adrian Huang88b8d332015-07-06 12:19:12 +080053 time64_t alarm_expires;
David Brownell7be2c7c2007-02-10 01:46:02 -080054
David Brownell87ac84f2007-05-08 00:34:00 -070055 void (*wake_on)(struct device *);
56 void (*wake_off)(struct device *);
57
58 u8 enabled_wake;
David Brownell7be2c7c2007-02-10 01:46:02 -080059 u8 suspend_ctrl;
60
61 /* newer hardware extends the original register set */
62 u8 day_alrm;
63 u8 mon_alrm;
64 u8 century;
65};
66
67/* both platform and pnp busses use negative numbers for invalid irqs */
Anton Vorontsov2fac6672009-01-06 14:42:11 -080068#define is_valid_irq(n) ((n) > 0)
David Brownell7be2c7c2007-02-10 01:46:02 -080069
70static const char driver_name[] = "rtc_cmos";
71
David Brownellbcd9b892007-04-01 23:49:47 -070072/* The RTC_INTR register may have e.g. RTC_PF set even if RTC_PIE is clear;
73 * always mask it against the irq enable bits in RTC_CONTROL. Bit values
74 * are the same: PF==PIE, AF=AIE, UF=UIE; so RTC_IRQMASK works with both.
75 */
76#define RTC_IRQMASK (RTC_PF | RTC_AF | RTC_UF)
77
78static inline int is_intr(u8 rtc_intr)
79{
80 if (!(rtc_intr & RTC_IRQF))
81 return 0;
82 return rtc_intr & RTC_IRQMASK;
83}
84
David Brownell7be2c7c2007-02-10 01:46:02 -080085/*----------------------------------------------------------------*/
86
David Brownell35d3fdd2008-07-23 21:30:43 -070087/* Much modern x86 hardware has HPETs (10+ MHz timers) which, because
88 * many BIOS programmers don't set up "sane mode" IRQ routing, are mostly
89 * used in a broken "legacy replacement" mode. The breakage includes
90 * HPET #1 hijacking the IRQ for this RTC, and being unavailable for
91 * other (better) use.
92 *
93 * When that broken mode is in use, platform glue provides a partial
94 * emulation of hardware RTC IRQ facilities using HPET #1. We don't
95 * want to use HPET for anything except those IRQs though...
96 */
97#ifdef CONFIG_HPET_EMULATE_RTC
98#include <asm/hpet.h>
99#else
100
101static inline int is_hpet_enabled(void)
102{
103 return 0;
104}
105
106static inline int hpet_mask_rtc_irq_bit(unsigned long mask)
107{
108 return 0;
109}
110
111static inline int hpet_set_rtc_irq_bit(unsigned long mask)
112{
113 return 0;
114}
115
116static inline int
117hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned char sec)
118{
119 return 0;
120}
121
122static inline int hpet_set_periodic_freq(unsigned long freq)
123{
124 return 0;
125}
126
127static inline int hpet_rtc_dropped_irq(void)
128{
129 return 0;
130}
131
132static inline int hpet_rtc_timer_init(void)
133{
134 return 0;
135}
136
137extern irq_handler_t hpet_rtc_interrupt;
138
139static inline int hpet_register_irq_handler(irq_handler_t handler)
140{
141 return 0;
142}
143
144static inline int hpet_unregister_irq_handler(irq_handler_t handler)
145{
146 return 0;
147}
148
149#endif
150
151/*----------------------------------------------------------------*/
152
David Brownellc8fc40c2008-10-18 20:27:47 -0700153#ifdef RTC_PORT
154
155/* Most newer x86 systems have two register banks, the first used
156 * for RTC and NVRAM and the second only for NVRAM. Caller must
157 * own rtc_lock ... and we won't worry about access during NMI.
158 */
159#define can_bank2 true
160
161static inline unsigned char cmos_read_bank2(unsigned char addr)
162{
163 outb(addr, RTC_PORT(2));
164 return inb(RTC_PORT(3));
165}
166
167static inline void cmos_write_bank2(unsigned char val, unsigned char addr)
168{
169 outb(addr, RTC_PORT(2));
Ondrej Zaryb43c1ea2012-01-10 15:10:26 -0800170 outb(val, RTC_PORT(3));
David Brownellc8fc40c2008-10-18 20:27:47 -0700171}
172
173#else
174
175#define can_bank2 false
176
177static inline unsigned char cmos_read_bank2(unsigned char addr)
178{
179 return 0;
180}
181
182static inline void cmos_write_bank2(unsigned char val, unsigned char addr)
183{
184}
185
186#endif
187
188/*----------------------------------------------------------------*/
189
David Brownell7be2c7c2007-02-10 01:46:02 -0800190static int cmos_read_time(struct device *dev, struct rtc_time *t)
191{
192 /* REVISIT: if the clock has a "century" register, use
Arnd Bergmann5ab788d2016-05-30 20:57:50 +0200193 * that instead of the heuristic in mc146818_get_time().
David Brownell7be2c7c2007-02-10 01:46:02 -0800194 * That'll make Y3K compatility (year > 2070) easy!
195 */
Arnd Bergmann5ab788d2016-05-30 20:57:50 +0200196 mc146818_get_time(t);
David Brownell7be2c7c2007-02-10 01:46:02 -0800197 return 0;
198}
199
200static int cmos_set_time(struct device *dev, struct rtc_time *t)
201{
202 /* REVISIT: set the "century" register if available
203 *
204 * NOTE: this ignores the issue whereby updating the seconds
205 * takes effect exactly 500ms after we write the register.
206 * (Also queueing and other delays before we get this far.)
207 */
Arnd Bergmann5ab788d2016-05-30 20:57:50 +0200208 return mc146818_set_time(t);
David Brownell7be2c7c2007-02-10 01:46:02 -0800209}
210
211static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
212{
213 struct cmos_rtc *cmos = dev_get_drvdata(dev);
214 unsigned char rtc_control;
215
216 if (!is_valid_irq(cmos->irq))
217 return -EIO;
218
219 /* Basic alarms only support hour, minute, and seconds fields.
220 * Some also support day and month, for alarms up to a year in
221 * the future.
222 */
David Brownell7be2c7c2007-02-10 01:46:02 -0800223
224 spin_lock_irq(&rtc_lock);
225 t->time.tm_sec = CMOS_READ(RTC_SECONDS_ALARM);
226 t->time.tm_min = CMOS_READ(RTC_MINUTES_ALARM);
227 t->time.tm_hour = CMOS_READ(RTC_HOURS_ALARM);
228
229 if (cmos->day_alrm) {
Mark Lord615bb292007-11-03 22:04:03 -0400230 /* ignore upper bits on readback per ACPI spec */
231 t->time.tm_mday = CMOS_READ(cmos->day_alrm) & 0x3f;
David Brownell7be2c7c2007-02-10 01:46:02 -0800232 if (!t->time.tm_mday)
233 t->time.tm_mday = -1;
234
235 if (cmos->mon_alrm) {
236 t->time.tm_mon = CMOS_READ(cmos->mon_alrm);
237 if (!t->time.tm_mon)
238 t->time.tm_mon = -1;
239 }
240 }
241
242 rtc_control = CMOS_READ(RTC_CONTROL);
243 spin_unlock_irq(&rtc_lock);
244
Arnaud Patard3804a892010-04-29 11:58:44 +0200245 if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
246 if (((unsigned)t->time.tm_sec) < 0x60)
247 t->time.tm_sec = bcd2bin(t->time.tm_sec);
David Brownell7be2c7c2007-02-10 01:46:02 -0800248 else
Arnaud Patard3804a892010-04-29 11:58:44 +0200249 t->time.tm_sec = -1;
250 if (((unsigned)t->time.tm_min) < 0x60)
251 t->time.tm_min = bcd2bin(t->time.tm_min);
252 else
253 t->time.tm_min = -1;
254 if (((unsigned)t->time.tm_hour) < 0x24)
255 t->time.tm_hour = bcd2bin(t->time.tm_hour);
256 else
257 t->time.tm_hour = -1;
258
259 if (cmos->day_alrm) {
260 if (((unsigned)t->time.tm_mday) <= 0x31)
261 t->time.tm_mday = bcd2bin(t->time.tm_mday);
David Brownell7be2c7c2007-02-10 01:46:02 -0800262 else
Arnaud Patard3804a892010-04-29 11:58:44 +0200263 t->time.tm_mday = -1;
264
265 if (cmos->mon_alrm) {
266 if (((unsigned)t->time.tm_mon) <= 0x12)
267 t->time.tm_mon = bcd2bin(t->time.tm_mon)-1;
268 else
269 t->time.tm_mon = -1;
270 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800271 }
272 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800273
274 t->enabled = !!(rtc_control & RTC_AIE);
275 t->pending = 0;
276
277 return 0;
278}
279
David Brownell7e2a31d2008-07-23 21:30:47 -0700280static void cmos_checkintr(struct cmos_rtc *cmos, unsigned char rtc_control)
281{
282 unsigned char rtc_intr;
283
284 /* NOTE after changing RTC_xIE bits we always read INTR_FLAGS;
285 * allegedly some older rtcs need that to handle irqs properly
286 */
287 rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
288
289 if (is_hpet_enabled())
290 return;
291
292 rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
293 if (is_intr(rtc_intr))
294 rtc_update_irq(cmos->rtc, 1, rtc_intr);
295}
296
297static void cmos_irq_enable(struct cmos_rtc *cmos, unsigned char mask)
298{
299 unsigned char rtc_control;
300
301 /* flush any pending IRQ status, notably for update irqs,
302 * before we enable new IRQs
303 */
304 rtc_control = CMOS_READ(RTC_CONTROL);
305 cmos_checkintr(cmos, rtc_control);
306
307 rtc_control |= mask;
308 CMOS_WRITE(rtc_control, RTC_CONTROL);
309 hpet_set_rtc_irq_bit(mask);
310
311 cmos_checkintr(cmos, rtc_control);
312}
313
314static void cmos_irq_disable(struct cmos_rtc *cmos, unsigned char mask)
315{
316 unsigned char rtc_control;
317
318 rtc_control = CMOS_READ(RTC_CONTROL);
319 rtc_control &= ~mask;
320 CMOS_WRITE(rtc_control, RTC_CONTROL);
321 hpet_mask_rtc_irq_bit(mask);
322
323 cmos_checkintr(cmos, rtc_control);
324}
325
David Brownell7be2c7c2007-02-10 01:46:02 -0800326static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
327{
328 struct cmos_rtc *cmos = dev_get_drvdata(dev);
Sachin Kamat5e8599d2013-07-03 15:05:45 -0700329 unsigned char mon, mday, hrs, min, sec, rtc_control;
David Brownell7be2c7c2007-02-10 01:46:02 -0800330
331 if (!is_valid_irq(cmos->irq))
332 return -EIO;
333
Zhao Yakui2b653e02008-04-15 14:34:29 -0700334 mon = t->time.tm_mon + 1;
David Brownell7be2c7c2007-02-10 01:46:02 -0800335 mday = t->time.tm_mday;
David Brownell7be2c7c2007-02-10 01:46:02 -0800336 hrs = t->time.tm_hour;
David Brownell7be2c7c2007-02-10 01:46:02 -0800337 min = t->time.tm_min;
David Brownell7be2c7c2007-02-10 01:46:02 -0800338 sec = t->time.tm_sec;
Arnaud Patard3804a892010-04-29 11:58:44 +0200339
340 rtc_control = CMOS_READ(RTC_CONTROL);
341 if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
342 /* Writing 0xff means "don't care" or "match all". */
343 mon = (mon <= 12) ? bin2bcd(mon) : 0xff;
344 mday = (mday >= 1 && mday <= 31) ? bin2bcd(mday) : 0xff;
345 hrs = (hrs < 24) ? bin2bcd(hrs) : 0xff;
346 min = (min < 60) ? bin2bcd(min) : 0xff;
347 sec = (sec < 60) ? bin2bcd(sec) : 0xff;
348 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800349
350 spin_lock_irq(&rtc_lock);
351
352 /* next rtc irq must not be from previous alarm setting */
David Brownell7e2a31d2008-07-23 21:30:47 -0700353 cmos_irq_disable(cmos, RTC_AIE);
David Brownell7be2c7c2007-02-10 01:46:02 -0800354
355 /* update alarm */
356 CMOS_WRITE(hrs, RTC_HOURS_ALARM);
357 CMOS_WRITE(min, RTC_MINUTES_ALARM);
358 CMOS_WRITE(sec, RTC_SECONDS_ALARM);
359
360 /* the system may support an "enhanced" alarm */
361 if (cmos->day_alrm) {
362 CMOS_WRITE(mday, cmos->day_alrm);
363 if (cmos->mon_alrm)
364 CMOS_WRITE(mon, cmos->mon_alrm);
365 }
366
David Brownell35d3fdd2008-07-23 21:30:43 -0700367 /* FIXME the HPET alarm glue currently ignores day_alrm
368 * and mon_alrm ...
369 */
370 hpet_set_alarm_time(t->time.tm_hour, t->time.tm_min, t->time.tm_sec);
371
David Brownell7e2a31d2008-07-23 21:30:47 -0700372 if (t->enabled)
373 cmos_irq_enable(cmos, RTC_AIE);
David Brownell7be2c7c2007-02-10 01:46:02 -0800374
375 spin_unlock_irq(&rtc_lock);
376
Adrian Huang88b8d332015-07-06 12:19:12 +0800377 cmos->alarm_expires = rtc_tm_to_time64(&t->time);
378
David Brownell7be2c7c2007-02-10 01:46:02 -0800379 return 0;
380}
381
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800382static int cmos_alarm_irq_enable(struct device *dev, unsigned int enabled)
David Brownell7be2c7c2007-02-10 01:46:02 -0800383{
384 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownell7be2c7c2007-02-10 01:46:02 -0800385 unsigned long flags;
386
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800387 if (!is_valid_irq(cmos->irq))
388 return -EINVAL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800389
390 spin_lock_irqsave(&rtc_lock, flags);
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800391
392 if (enabled)
David Brownell7e2a31d2008-07-23 21:30:47 -0700393 cmos_irq_enable(cmos, RTC_AIE);
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800394 else
395 cmos_irq_disable(cmos, RTC_AIE);
396
David Brownell7be2c7c2007-02-10 01:46:02 -0800397 spin_unlock_irqrestore(&rtc_lock, flags);
398 return 0;
399}
400
Javier Martinez Canillas6fca3fc2016-04-26 18:17:35 -0400401#if IS_ENABLED(CONFIG_RTC_INTF_PROC)
David Brownell7be2c7c2007-02-10 01:46:02 -0800402
403static int cmos_procfs(struct device *dev, struct seq_file *seq)
404{
405 struct cmos_rtc *cmos = dev_get_drvdata(dev);
406 unsigned char rtc_control, valid;
407
408 spin_lock_irq(&rtc_lock);
409 rtc_control = CMOS_READ(RTC_CONTROL);
410 valid = CMOS_READ(RTC_VALID);
411 spin_unlock_irq(&rtc_lock);
412
413 /* NOTE: at least ICH6 reports battery status using a different
414 * (non-RTC) bit; and SQWE is ignored on many current systems.
415 */
Joe Perches4395eb12015-04-15 16:17:51 -0700416 seq_printf(seq,
417 "periodic_IRQ\t: %s\n"
418 "update_IRQ\t: %s\n"
419 "HPET_emulated\t: %s\n"
420 // "square_wave\t: %s\n"
421 "BCD\t\t: %s\n"
422 "DST_enable\t: %s\n"
423 "periodic_freq\t: %d\n"
424 "batt_status\t: %s\n",
425 (rtc_control & RTC_PIE) ? "yes" : "no",
426 (rtc_control & RTC_UIE) ? "yes" : "no",
427 is_hpet_enabled() ? "yes" : "no",
428 // (rtc_control & RTC_SQWE) ? "yes" : "no",
429 (rtc_control & RTC_DM_BINARY) ? "no" : "yes",
430 (rtc_control & RTC_DST_EN) ? "yes" : "no",
431 cmos->rtc->irq_freq,
432 (valid & RTC_VRT) ? "okay" : "dead");
433
434 return 0;
David Brownell7be2c7c2007-02-10 01:46:02 -0800435}
436
437#else
438#define cmos_procfs NULL
439#endif
440
441static const struct rtc_class_ops cmos_rtc_ops = {
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800442 .read_time = cmos_read_time,
443 .set_time = cmos_set_time,
444 .read_alarm = cmos_read_alarm,
445 .set_alarm = cmos_set_alarm,
446 .proc = cmos_procfs,
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800447 .alarm_irq_enable = cmos_alarm_irq_enable,
David Brownell7be2c7c2007-02-10 01:46:02 -0800448};
449
450/*----------------------------------------------------------------*/
451
David Brownelle07e2322008-02-06 01:38:43 -0800452/*
453 * All these chips have at least 64 bytes of address space, shared by
454 * RTC registers and NVRAM. Most of those bytes of NVRAM are used
455 * by boot firmware. Modern chips have 128 or 256 bytes.
456 */
457
458#define NVRAM_OFFSET (RTC_REG_D + 1)
459
460static ssize_t
Chris Wright2c3c8be2010-05-12 18:28:57 -0700461cmos_nvram_read(struct file *filp, struct kobject *kobj,
462 struct bin_attribute *attr,
David Brownelle07e2322008-02-06 01:38:43 -0800463 char *buf, loff_t off, size_t count)
464{
465 int retval;
466
David Brownellc8fc40c2008-10-18 20:27:47 -0700467 off += NVRAM_OFFSET;
David Brownelle07e2322008-02-06 01:38:43 -0800468 spin_lock_irq(&rtc_lock);
David Brownellc8fc40c2008-10-18 20:27:47 -0700469 for (retval = 0; count; count--, off++, retval++) {
470 if (off < 128)
471 *buf++ = CMOS_READ(off);
472 else if (can_bank2)
473 *buf++ = cmos_read_bank2(off);
474 else
475 break;
476 }
David Brownelle07e2322008-02-06 01:38:43 -0800477 spin_unlock_irq(&rtc_lock);
478
479 return retval;
480}
481
482static ssize_t
Chris Wright2c3c8be2010-05-12 18:28:57 -0700483cmos_nvram_write(struct file *filp, struct kobject *kobj,
484 struct bin_attribute *attr,
David Brownelle07e2322008-02-06 01:38:43 -0800485 char *buf, loff_t off, size_t count)
486{
487 struct cmos_rtc *cmos;
488 int retval;
489
490 cmos = dev_get_drvdata(container_of(kobj, struct device, kobj));
David Brownelle07e2322008-02-06 01:38:43 -0800491
492 /* NOTE: on at least PCs and Ataris, the boot firmware uses a
493 * checksum on part of the NVRAM data. That's currently ignored
494 * here. If userspace is smart enough to know what fields of
495 * NVRAM to update, updating checksums is also part of its job.
496 */
David Brownellc8fc40c2008-10-18 20:27:47 -0700497 off += NVRAM_OFFSET;
David Brownelle07e2322008-02-06 01:38:43 -0800498 spin_lock_irq(&rtc_lock);
David Brownellc8fc40c2008-10-18 20:27:47 -0700499 for (retval = 0; count; count--, off++, retval++) {
David Brownelle07e2322008-02-06 01:38:43 -0800500 /* don't trash RTC registers */
501 if (off == cmos->day_alrm
502 || off == cmos->mon_alrm
503 || off == cmos->century)
504 buf++;
David Brownellc8fc40c2008-10-18 20:27:47 -0700505 else if (off < 128)
David Brownelle07e2322008-02-06 01:38:43 -0800506 CMOS_WRITE(*buf++, off);
David Brownellc8fc40c2008-10-18 20:27:47 -0700507 else if (can_bank2)
508 cmos_write_bank2(*buf++, off);
509 else
510 break;
David Brownelle07e2322008-02-06 01:38:43 -0800511 }
512 spin_unlock_irq(&rtc_lock);
513
514 return retval;
515}
516
517static struct bin_attribute nvram = {
518 .attr = {
519 .name = "nvram",
520 .mode = S_IRUGO | S_IWUSR,
David Brownelle07e2322008-02-06 01:38:43 -0800521 },
522
523 .read = cmos_nvram_read,
524 .write = cmos_nvram_write,
525 /* size gets set up later */
526};
527
528/*----------------------------------------------------------------*/
529
David Brownell7be2c7c2007-02-10 01:46:02 -0800530static struct cmos_rtc cmos_rtc;
531
532static irqreturn_t cmos_interrupt(int irq, void *p)
533{
534 u8 irqstat;
David Brownell8a0bdfd2008-02-06 01:38:45 -0800535 u8 rtc_control;
David Brownell7be2c7c2007-02-10 01:46:02 -0800536
537 spin_lock(&rtc_lock);
David Brownell35d3fdd2008-07-23 21:30:43 -0700538
539 /* When the HPET interrupt handler calls us, the interrupt
540 * status is passed as arg1 instead of the irq number. But
541 * always clear irq status, even when HPET is in the way.
542 *
543 * Note that HPET and RTC are almost certainly out of phase,
544 * giving different IRQ status ...
Bernhard Walle9d8af782008-02-06 01:38:52 -0800545 */
David Brownell35d3fdd2008-07-23 21:30:43 -0700546 irqstat = CMOS_READ(RTC_INTR_FLAGS);
547 rtc_control = CMOS_READ(RTC_CONTROL);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800548 if (is_hpet_enabled())
549 irqstat = (unsigned long)irq & 0xF0;
Derek Basehore998a0602013-07-03 15:07:54 -0700550
551 /* If we were suspended, RTC_CONTROL may not be accurate since the
552 * bios may have cleared it.
553 */
554 if (!cmos_rtc.suspend_ctrl)
555 irqstat &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
556 else
557 irqstat &= (cmos_rtc.suspend_ctrl & RTC_IRQMASK) | RTC_IRQF;
David Brownell8a0bdfd2008-02-06 01:38:45 -0800558
559 /* All Linux RTC alarms should be treated as if they were oneshot.
560 * Similar code may be needed in system wakeup paths, in case the
561 * alarm woke the system.
562 */
563 if (irqstat & RTC_AIE) {
Derek Basehore998a0602013-07-03 15:07:54 -0700564 cmos_rtc.suspend_ctrl &= ~RTC_AIE;
David Brownell8a0bdfd2008-02-06 01:38:45 -0800565 rtc_control &= ~RTC_AIE;
566 CMOS_WRITE(rtc_control, RTC_CONTROL);
David Brownell35d3fdd2008-07-23 21:30:43 -0700567 hpet_mask_rtc_irq_bit(RTC_AIE);
David Brownell8a0bdfd2008-02-06 01:38:45 -0800568 CMOS_READ(RTC_INTR_FLAGS);
569 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800570 spin_unlock(&rtc_lock);
571
David Brownellbcd9b892007-04-01 23:49:47 -0700572 if (is_intr(irqstat)) {
David Brownell7be2c7c2007-02-10 01:46:02 -0800573 rtc_update_irq(p, 1, irqstat);
574 return IRQ_HANDLED;
575 } else
576 return IRQ_NONE;
577}
578
Marko Vrh41ac8df2007-05-08 00:34:09 -0700579#ifdef CONFIG_PNP
David Brownell7be2c7c2007-02-10 01:46:02 -0800580#define INITSECTION
581
582#else
David Brownell7be2c7c2007-02-10 01:46:02 -0800583#define INITSECTION __init
584#endif
585
586static int INITSECTION
587cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
588{
Jingoo Han97a92e72013-11-12 15:10:38 -0800589 struct cmos_rtc_board_info *info = dev_get_platdata(dev);
David Brownell7be2c7c2007-02-10 01:46:02 -0800590 int retval = 0;
591 unsigned char rtc_control;
David Brownelle07e2322008-02-06 01:38:43 -0800592 unsigned address_space;
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700593 u32 flags = 0;
David Brownell7be2c7c2007-02-10 01:46:02 -0800594
595 /* there can be only one ... */
596 if (cmos_rtc.dev)
597 return -EBUSY;
598
599 if (!ports)
600 return -ENODEV;
601
David Brownell05440df2007-10-16 01:28:21 -0700602 /* Claim I/O ports ASAP, minimizing conflict with legacy driver.
603 *
604 * REVISIT non-x86 systems may instead use memory space resources
605 * (needing ioremap etc), not i/o space resources like this ...
606 */
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700607 if (RTC_IOMAPPED)
608 ports = request_region(ports->start, resource_size(ports),
609 driver_name);
610 else
611 ports = request_mem_region(ports->start, resource_size(ports),
612 driver_name);
David Brownell05440df2007-10-16 01:28:21 -0700613 if (!ports) {
614 dev_dbg(dev, "i/o registers already in use\n");
615 return -EBUSY;
616 }
617
David Brownell7be2c7c2007-02-10 01:46:02 -0800618 cmos_rtc.irq = rtc_irq;
619 cmos_rtc.iomem = ports;
620
David Brownelle07e2322008-02-06 01:38:43 -0800621 /* Heuristic to deduce NVRAM size ... do what the legacy NVRAM
622 * driver did, but don't reject unknown configs. Old hardware
David Brownellc8fc40c2008-10-18 20:27:47 -0700623 * won't address 128 bytes. Newer chips have multiple banks,
624 * though they may not be listed in one I/O resource.
David Brownelle07e2322008-02-06 01:38:43 -0800625 */
626#if defined(CONFIG_ATARI)
627 address_space = 64;
Wu Zhangjin95abd0d2009-11-05 09:21:54 +0800628#elif defined(__i386__) || defined(__x86_64__) || defined(__arm__) \
Srikanth Krishnakar8cb7c712010-10-14 04:03:35 +0000629 || defined(__sparc__) || defined(__mips__) \
Arnd Bergmann5ee98ab2016-06-01 16:46:22 +0200630 || defined(__powerpc__) || defined(CONFIG_MN10300)
David Brownelle07e2322008-02-06 01:38:43 -0800631 address_space = 128;
632#else
633#warning Assuming 128 bytes of RTC+NVRAM address space, not 64 bytes.
634 address_space = 128;
635#endif
David Brownellc8fc40c2008-10-18 20:27:47 -0700636 if (can_bank2 && ports->end > (ports->start + 1))
637 address_space = 256;
David Brownelle07e2322008-02-06 01:38:43 -0800638
David Brownell87ac84f2007-05-08 00:34:00 -0700639 /* For ACPI systems extension info comes from the FADT. On others,
640 * board specific setup provides it as appropriate. Systems where
641 * the alarm IRQ isn't automatically a wakeup IRQ (like ACPI, and
642 * some almost-clones) can provide hooks to make that behave.
David Brownelle07e2322008-02-06 01:38:43 -0800643 *
644 * Note that ACPI doesn't preclude putting these registers into
645 * "extended" areas of the chip, including some that we won't yet
646 * expect CMOS_READ and friends to handle.
David Brownell7be2c7c2007-02-10 01:46:02 -0800647 */
648 if (info) {
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700649 if (info->flags)
650 flags = info->flags;
651 if (info->address_space)
652 address_space = info->address_space;
653
David Brownelle07e2322008-02-06 01:38:43 -0800654 if (info->rtc_day_alarm && info->rtc_day_alarm < 128)
655 cmos_rtc.day_alrm = info->rtc_day_alarm;
656 if (info->rtc_mon_alarm && info->rtc_mon_alarm < 128)
657 cmos_rtc.mon_alrm = info->rtc_mon_alarm;
658 if (info->rtc_century && info->rtc_century < 128)
659 cmos_rtc.century = info->rtc_century;
David Brownell87ac84f2007-05-08 00:34:00 -0700660
661 if (info->wake_on && info->wake_off) {
662 cmos_rtc.wake_on = info->wake_on;
663 cmos_rtc.wake_off = info->wake_off;
664 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800665 }
666
Dan Carpenter6ba8bcd2010-05-24 14:33:49 -0700667 cmos_rtc.dev = dev;
668 dev_set_drvdata(dev, &cmos_rtc);
669
David Brownell7be2c7c2007-02-10 01:46:02 -0800670 cmos_rtc.rtc = rtc_device_register(driver_name, dev,
671 &cmos_rtc_ops, THIS_MODULE);
David Brownell05440df2007-10-16 01:28:21 -0700672 if (IS_ERR(cmos_rtc.rtc)) {
673 retval = PTR_ERR(cmos_rtc.rtc);
674 goto cleanup0;
675 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800676
Kay Sieversd4afc762009-01-06 14:42:11 -0800677 rename_region(ports, dev_name(&cmos_rtc.rtc->dev));
David Brownell7be2c7c2007-02-10 01:46:02 -0800678
679 spin_lock_irq(&rtc_lock);
680
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700681 if (!(flags & CMOS_RTC_FLAGS_NOFREQ)) {
682 /* force periodic irq to CMOS reset default of 1024Hz;
683 *
684 * REVISIT it's been reported that at least one x86_64 ALI
685 * mobo doesn't use 32KHz here ... for portability we might
686 * need to do something about other clock frequencies.
687 */
688 cmos_rtc.rtc->irq_freq = 1024;
689 hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq);
690 CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
691 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800692
David Brownell7e2a31d2008-07-23 21:30:47 -0700693 /* disable irqs */
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700694 if (is_valid_irq(rtc_irq))
695 cmos_irq_disable(&cmos_rtc, RTC_PIE | RTC_AIE | RTC_UIE);
David Brownell35d3fdd2008-07-23 21:30:43 -0700696
David Brownell7e2a31d2008-07-23 21:30:47 -0700697 rtc_control = CMOS_READ(RTC_CONTROL);
David Brownell7be2c7c2007-02-10 01:46:02 -0800698
699 spin_unlock_irq(&rtc_lock);
700
Arnaud Patard3804a892010-04-29 11:58:44 +0200701 /* FIXME:
David Brownell7be2c7c2007-02-10 01:46:02 -0800702 * <asm-generic/rtc.h> doesn't know 12-hour mode either.
703 */
Sachin Kamat5e8599d2013-07-03 15:05:45 -0700704 if (is_valid_irq(rtc_irq) && !(rtc_control & RTC_24H)) {
Arnaud Patard3804a892010-04-29 11:58:44 +0200705 dev_warn(dev, "only 24-hr supported\n");
David Brownell7be2c7c2007-02-10 01:46:02 -0800706 retval = -ENXIO;
707 goto cleanup1;
708 }
709
Bernhard Walle9d8af782008-02-06 01:38:52 -0800710 if (is_valid_irq(rtc_irq)) {
711 irq_handler_t rtc_cmos_int_handler;
712
713 if (is_hpet_enabled()) {
Bernhard Walle9d8af782008-02-06 01:38:52 -0800714 rtc_cmos_int_handler = hpet_rtc_interrupt;
Andrew Morton24b34472014-01-23 15:55:15 -0800715 retval = hpet_register_irq_handler(cmos_interrupt);
716 if (retval) {
Jingoo Hanee443352013-02-21 16:45:34 -0800717 dev_warn(dev, "hpet_register_irq_handler "
Bernhard Walle9d8af782008-02-06 01:38:52 -0800718 " failed in rtc_init().");
719 goto cleanup1;
720 }
721 } else
722 rtc_cmos_int_handler = cmos_interrupt;
723
724 retval = request_irq(rtc_irq, rtc_cmos_int_handler,
Andy Shevchenko079062b2015-12-23 19:37:19 +0200725 IRQF_SHARED, dev_name(&cmos_rtc.rtc->dev),
David Brownellab6a2d72007-05-08 00:33:30 -0700726 cmos_rtc.rtc);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800727 if (retval < 0) {
728 dev_dbg(dev, "IRQ %d is already in use\n", rtc_irq);
729 goto cleanup1;
730 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800731 }
Bernhard Walle9d8af782008-02-06 01:38:52 -0800732 hpet_rtc_timer_init();
David Brownell7be2c7c2007-02-10 01:46:02 -0800733
David Brownelle07e2322008-02-06 01:38:43 -0800734 /* export at least the first block of NVRAM */
735 nvram.size = address_space - NVRAM_OFFSET;
736 retval = sysfs_create_bin_file(&dev->kobj, &nvram);
737 if (retval < 0) {
738 dev_dbg(dev, "can't create nvram file? %d\n", retval);
739 goto cleanup2;
740 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800741
Jingoo Hanee443352013-02-21 16:45:34 -0800742 dev_info(dev, "%s%s, %zd bytes nvram%s\n",
Krzysztof Halasa6d029b62009-04-21 12:24:49 -0700743 !is_valid_irq(rtc_irq) ? "no alarms" :
744 cmos_rtc.mon_alrm ? "alarms up to one year" :
745 cmos_rtc.day_alrm ? "alarms up to one month" :
746 "alarms up to one day",
747 cmos_rtc.century ? ", y3k" : "",
748 nvram.size,
749 is_hpet_enabled() ? ", hpet irqs" : "");
David Brownell7be2c7c2007-02-10 01:46:02 -0800750
751 return 0;
752
David Brownelle07e2322008-02-06 01:38:43 -0800753cleanup2:
754 if (is_valid_irq(rtc_irq))
755 free_irq(rtc_irq, cmos_rtc.rtc);
David Brownell7be2c7c2007-02-10 01:46:02 -0800756cleanup1:
David Brownell05440df2007-10-16 01:28:21 -0700757 cmos_rtc.dev = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800758 rtc_device_unregister(cmos_rtc.rtc);
David Brownell05440df2007-10-16 01:28:21 -0700759cleanup0:
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700760 if (RTC_IOMAPPED)
761 release_region(ports->start, resource_size(ports));
762 else
763 release_mem_region(ports->start, resource_size(ports));
David Brownell7be2c7c2007-02-10 01:46:02 -0800764 return retval;
765}
766
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700767static void cmos_do_shutdown(int rtc_irq)
David Brownell7be2c7c2007-02-10 01:46:02 -0800768{
David Brownell7be2c7c2007-02-10 01:46:02 -0800769 spin_lock_irq(&rtc_lock);
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700770 if (is_valid_irq(rtc_irq))
771 cmos_irq_disable(&cmos_rtc, RTC_IRQMASK);
David Brownell7be2c7c2007-02-10 01:46:02 -0800772 spin_unlock_irq(&rtc_lock);
773}
774
775static void __exit cmos_do_remove(struct device *dev)
776{
777 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownell05440df2007-10-16 01:28:21 -0700778 struct resource *ports;
David Brownell7be2c7c2007-02-10 01:46:02 -0800779
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700780 cmos_do_shutdown(cmos->irq);
David Brownell7be2c7c2007-02-10 01:46:02 -0800781
David Brownelle07e2322008-02-06 01:38:43 -0800782 sysfs_remove_bin_file(&dev->kobj, &nvram);
783
Bernhard Walle9d8af782008-02-06 01:38:52 -0800784 if (is_valid_irq(cmos->irq)) {
David Brownell05440df2007-10-16 01:28:21 -0700785 free_irq(cmos->irq, cmos->rtc);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800786 hpet_unregister_irq_handler(cmos_interrupt);
787 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800788
David Brownell05440df2007-10-16 01:28:21 -0700789 rtc_device_unregister(cmos->rtc);
790 cmos->rtc = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800791
David Brownell05440df2007-10-16 01:28:21 -0700792 ports = cmos->iomem;
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700793 if (RTC_IOMAPPED)
794 release_region(ports->start, resource_size(ports));
795 else
796 release_mem_region(ports->start, resource_size(ports));
David Brownell05440df2007-10-16 01:28:21 -0700797 cmos->iomem = NULL;
798
799 cmos->dev = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800800}
801
Adrian Huang88b8d332015-07-06 12:19:12 +0800802static int cmos_aie_poweroff(struct device *dev)
803{
804 struct cmos_rtc *cmos = dev_get_drvdata(dev);
805 struct rtc_time now;
806 time64_t t_now;
807 int retval = 0;
808 unsigned char rtc_control;
809
810 if (!cmos->alarm_expires)
811 return -EINVAL;
812
813 spin_lock_irq(&rtc_lock);
814 rtc_control = CMOS_READ(RTC_CONTROL);
815 spin_unlock_irq(&rtc_lock);
816
817 /* We only care about the situation where AIE is disabled. */
818 if (rtc_control & RTC_AIE)
819 return -EBUSY;
820
821 cmos_read_time(dev, &now);
822 t_now = rtc_tm_to_time64(&now);
823
824 /*
825 * When enabling "RTC wake-up" in BIOS setup, the machine reboots
826 * automatically right after shutdown on some buggy boxes.
827 * This automatic rebooting issue won't happen when the alarm
828 * time is larger than now+1 seconds.
829 *
830 * If the alarm time is equal to now+1 seconds, the issue can be
831 * prevented by cancelling the alarm.
832 */
833 if (cmos->alarm_expires == t_now + 1) {
834 struct rtc_wkalrm alarm;
835
836 /* Cancel the AIE timer by configuring the past time. */
837 rtc_time64_to_tm(t_now - 1, &alarm.time);
838 alarm.enabled = 0;
839 retval = cmos_set_alarm(dev, &alarm);
840 } else if (cmos->alarm_expires > t_now + 1) {
841 retval = -EBUSY;
842 }
843
844 return retval;
845}
846
Daniel Glöcknera882b142014-10-13 15:53:16 -0700847#ifdef CONFIG_PM
David Brownell7be2c7c2007-02-10 01:46:02 -0800848
Paul Fox2fb08e62011-01-12 17:00:07 -0800849static int cmos_suspend(struct device *dev)
David Brownell7be2c7c2007-02-10 01:46:02 -0800850{
851 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownellbcd9b892007-04-01 23:49:47 -0700852 unsigned char tmp;
David Brownell7be2c7c2007-02-10 01:46:02 -0800853
854 /* only the alarm might be a wakeup event source */
855 spin_lock_irq(&rtc_lock);
856 cmos->suspend_ctrl = tmp = CMOS_READ(RTC_CONTROL);
857 if (tmp & (RTC_PIE|RTC_AIE|RTC_UIE)) {
David Brownell35d3fdd2008-07-23 21:30:43 -0700858 unsigned char mask;
David Brownellbcd9b892007-04-01 23:49:47 -0700859
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700860 if (device_may_wakeup(dev))
David Brownell35d3fdd2008-07-23 21:30:43 -0700861 mask = RTC_IRQMASK & ~RTC_AIE;
David Brownell7be2c7c2007-02-10 01:46:02 -0800862 else
David Brownell35d3fdd2008-07-23 21:30:43 -0700863 mask = RTC_IRQMASK;
864 tmp &= ~mask;
David Brownell7be2c7c2007-02-10 01:46:02 -0800865 CMOS_WRITE(tmp, RTC_CONTROL);
Derek Basehoree0057152013-04-29 16:20:23 -0700866 hpet_mask_rtc_irq_bit(mask);
David Brownell35d3fdd2008-07-23 21:30:43 -0700867
David Brownell7e2a31d2008-07-23 21:30:47 -0700868 cmos_checkintr(cmos, tmp);
David Brownellbcd9b892007-04-01 23:49:47 -0700869 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800870 spin_unlock_irq(&rtc_lock);
871
David Brownell87ac84f2007-05-08 00:34:00 -0700872 if (tmp & RTC_AIE) {
873 cmos->enabled_wake = 1;
874 if (cmos->wake_on)
875 cmos->wake_on(dev);
876 else
877 enable_irq_wake(cmos->irq);
878 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800879
Jingoo Hanee443352013-02-21 16:45:34 -0800880 dev_dbg(dev, "suspend%s, ctrl %02x\n",
David Brownell7be2c7c2007-02-10 01:46:02 -0800881 (tmp & RTC_AIE) ? ", alarm may wake" : "",
882 tmp);
883
884 return 0;
885}
886
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700887/* We want RTC alarms to wake us from e.g. ACPI G2/S5 "soft off", even
888 * after a detour through G3 "mechanical off", although the ACPI spec
889 * says wakeup should only work from G1/S4 "hibernate". To most users,
890 * distinctions between S4 and S5 are pointless. So when the hardware
891 * allows, don't draw that distinction.
892 */
893static inline int cmos_poweroff(struct device *dev)
894{
Paul Fox2fb08e62011-01-12 17:00:07 -0800895 return cmos_suspend(dev);
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700896}
897
Daniel Glöcknera882b142014-10-13 15:53:16 -0700898#ifdef CONFIG_PM_SLEEP
899
David Brownell7be2c7c2007-02-10 01:46:02 -0800900static int cmos_resume(struct device *dev)
901{
902 struct cmos_rtc *cmos = dev_get_drvdata(dev);
Derek Basehore998a0602013-07-03 15:07:54 -0700903 unsigned char tmp;
David Brownell7be2c7c2007-02-10 01:46:02 -0800904
Derek Basehore998a0602013-07-03 15:07:54 -0700905 if (cmos->enabled_wake) {
906 if (cmos->wake_off)
907 cmos->wake_off(dev);
908 else
909 disable_irq_wake(cmos->irq);
910 cmos->enabled_wake = 0;
911 }
912
913 spin_lock_irq(&rtc_lock);
914 tmp = cmos->suspend_ctrl;
915 cmos->suspend_ctrl = 0;
David Brownell7be2c7c2007-02-10 01:46:02 -0800916 /* re-enable any irqs previously active */
David Brownell35d3fdd2008-07-23 21:30:43 -0700917 if (tmp & RTC_IRQMASK) {
918 unsigned char mask;
David Brownell7be2c7c2007-02-10 01:46:02 -0800919
Derek Basehoreebf8d6c2013-06-12 14:04:45 -0700920 if (device_may_wakeup(dev))
921 hpet_rtc_timer_init();
922
David Brownell35d3fdd2008-07-23 21:30:43 -0700923 do {
924 CMOS_WRITE(tmp, RTC_CONTROL);
925 hpet_set_rtc_irq_bit(tmp & RTC_IRQMASK);
926
927 mask = CMOS_READ(RTC_INTR_FLAGS);
928 mask &= (tmp & RTC_IRQMASK) | RTC_IRQF;
David Brownell7e2a31d2008-07-23 21:30:47 -0700929 if (!is_hpet_enabled() || !is_intr(mask))
David Brownell35d3fdd2008-07-23 21:30:43 -0700930 break;
931
932 /* force one-shot behavior if HPET blocked
933 * the wake alarm's irq
934 */
935 rtc_update_irq(cmos->rtc, 1, mask);
936 tmp &= ~RTC_AIE;
937 hpet_mask_rtc_irq_bit(RTC_AIE);
938 } while (mask & RTC_AIE);
David Brownell7be2c7c2007-02-10 01:46:02 -0800939 }
Derek Basehore998a0602013-07-03 15:07:54 -0700940 spin_unlock_irq(&rtc_lock);
David Brownell7be2c7c2007-02-10 01:46:02 -0800941
Jingoo Hanee443352013-02-21 16:45:34 -0800942 dev_dbg(dev, "resume, ctrl %02x\n", tmp);
David Brownell7be2c7c2007-02-10 01:46:02 -0800943
944 return 0;
945}
946
Daniel Glöcknera882b142014-10-13 15:53:16 -0700947#endif
David Brownell7be2c7c2007-02-10 01:46:02 -0800948#else
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700949
950static inline int cmos_poweroff(struct device *dev)
951{
952 return -ENOSYS;
953}
954
David Brownell7be2c7c2007-02-10 01:46:02 -0800955#endif
956
Mika Westerbergb5ada462014-04-03 14:50:05 -0700957static SIMPLE_DEV_PM_OPS(cmos_pm_ops, cmos_suspend, cmos_resume);
958
David Brownell7be2c7c2007-02-10 01:46:02 -0800959/*----------------------------------------------------------------*/
960
David Brownelle07e2322008-02-06 01:38:43 -0800961/* On non-x86 systems, a "CMOS" RTC lives most naturally on platform_bus.
962 * ACPI systems always list these as PNPACPI devices, and pre-ACPI PCs
963 * probably list them in similar PNPBIOS tables; so PNP is more common.
964 *
965 * We don't use legacy "poke at the hardware" probing. Ancient PCs that
966 * predate even PNPBIOS should set up platform_bus devices.
David Brownell7be2c7c2007-02-10 01:46:02 -0800967 */
968
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600969#ifdef CONFIG_ACPI
970
971#include <linux/acpi.h>
972
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600973static u32 rtc_handler(void *context)
974{
Daniel Drakeb2201e52012-05-18 22:59:41 +0200975 struct device *dev = context;
976
977 pm_wakeup_event(dev, 0);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600978 acpi_clear_event(ACPI_EVENT_RTC);
979 acpi_disable_event(ACPI_EVENT_RTC, 0);
980 return ACPI_INTERRUPT_HANDLED;
981}
982
Daniel Drakeb2201e52012-05-18 22:59:41 +0200983static inline void rtc_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600984{
Daniel Drakeb2201e52012-05-18 22:59:41 +0200985 acpi_install_fixed_event_handler(ACPI_EVENT_RTC, rtc_handler, dev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600986 /*
987 * After the RTC handler is installed, the Fixed_RTC event should
988 * be disabled. Only when the RTC alarm is set will it be enabled.
989 */
990 acpi_clear_event(ACPI_EVENT_RTC);
991 acpi_disable_event(ACPI_EVENT_RTC, 0);
992}
993
994static void rtc_wake_on(struct device *dev)
995{
996 acpi_clear_event(ACPI_EVENT_RTC);
997 acpi_enable_event(ACPI_EVENT_RTC, 0);
998}
999
1000static void rtc_wake_off(struct device *dev)
1001{
1002 acpi_disable_event(ACPI_EVENT_RTC, 0);
1003}
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001004
1005/* Every ACPI platform has a mc146818 compatible "cmos rtc". Here we find
1006 * its device node and pass extra config data. This helps its driver use
1007 * capabilities that the now-obsolete mc146818 didn't have, and informs it
1008 * that this board's RTC is wakeup-capable (per ACPI spec).
1009 */
1010static struct cmos_rtc_board_info acpi_rtc_info;
1011
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -08001012static void cmos_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001013{
1014 if (acpi_disabled)
1015 return;
1016
Daniel Drakeb2201e52012-05-18 22:59:41 +02001017 rtc_wake_setup(dev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001018 acpi_rtc_info.wake_on = rtc_wake_on;
1019 acpi_rtc_info.wake_off = rtc_wake_off;
1020
1021 /* workaround bug in some ACPI tables */
1022 if (acpi_gbl_FADT.month_alarm && !acpi_gbl_FADT.day_alarm) {
1023 dev_dbg(dev, "bogus FADT month_alarm (%d)\n",
1024 acpi_gbl_FADT.month_alarm);
1025 acpi_gbl_FADT.month_alarm = 0;
1026 }
1027
1028 acpi_rtc_info.rtc_day_alarm = acpi_gbl_FADT.day_alarm;
1029 acpi_rtc_info.rtc_mon_alarm = acpi_gbl_FADT.month_alarm;
1030 acpi_rtc_info.rtc_century = acpi_gbl_FADT.century;
1031
1032 /* NOTE: S4_RTC_WAKE is NOT currently useful to Linux */
1033 if (acpi_gbl_FADT.flags & ACPI_FADT_S4_RTC_WAKE)
1034 dev_info(dev, "RTC can wake from S4\n");
1035
1036 dev->platform_data = &acpi_rtc_info;
1037
1038 /* RTC always wakes from S1/S2/S3, and often S4/STD */
1039 device_init_wakeup(dev, 1);
1040}
1041
1042#else
1043
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -08001044static void cmos_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001045{
1046}
1047
1048#endif
1049
Marko Vrh41ac8df2007-05-08 00:34:09 -07001050#ifdef CONFIG_PNP
David Brownell7be2c7c2007-02-10 01:46:02 -08001051
1052#include <linux/pnp.h>
1053
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -08001054static int cmos_pnp_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
David Brownell7be2c7c2007-02-10 01:46:02 -08001055{
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001056 cmos_wake_setup(&pnp->dev);
1057
Sachin Kamat5e8599d2013-07-03 15:05:45 -07001058 if (pnp_port_start(pnp, 0) == 0x70 && !pnp_irq_valid(pnp, 0))
Matthew Garrett6cd8fa82007-06-01 00:46:51 -07001059 /* Some machines contain a PNP entry for the RTC, but
1060 * don't define the IRQ. It should always be safe to
1061 * hardcode it in these cases
1062 */
Bjorn Helgaas8766ad02008-04-28 16:34:27 -06001063 return cmos_do_probe(&pnp->dev,
1064 pnp_get_resource(pnp, IORESOURCE_IO, 0), 8);
Matthew Garrett6cd8fa82007-06-01 00:46:51 -07001065 else
1066 return cmos_do_probe(&pnp->dev,
Bjorn Helgaas8766ad02008-04-28 16:34:27 -06001067 pnp_get_resource(pnp, IORESOURCE_IO, 0),
1068 pnp_irq(pnp, 0));
David Brownell7be2c7c2007-02-10 01:46:02 -08001069}
1070
1071static void __exit cmos_pnp_remove(struct pnp_dev *pnp)
1072{
1073 cmos_do_remove(&pnp->dev);
1074}
1075
OGAWA Hirofumi004731b2010-01-08 14:43:11 -08001076static void cmos_pnp_shutdown(struct pnp_dev *pnp)
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001077{
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001078 struct device *dev = &pnp->dev;
1079 struct cmos_rtc *cmos = dev_get_drvdata(dev);
1080
Adrian Huang88b8d332015-07-06 12:19:12 +08001081 if (system_state == SYSTEM_POWER_OFF) {
1082 int retval = cmos_poweroff(dev);
1083
1084 if (cmos_aie_poweroff(dev) < 0 && !retval)
1085 return;
1086 }
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001087
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001088 cmos_do_shutdown(cmos->irq);
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001089}
David Brownell7be2c7c2007-02-10 01:46:02 -08001090
1091static const struct pnp_device_id rtc_ids[] = {
1092 { .id = "PNP0b00", },
1093 { .id = "PNP0b01", },
1094 { .id = "PNP0b02", },
1095 { },
1096};
1097MODULE_DEVICE_TABLE(pnp, rtc_ids);
1098
1099static struct pnp_driver cmos_pnp_driver = {
1100 .name = (char *) driver_name,
1101 .id_table = rtc_ids,
1102 .probe = cmos_pnp_probe,
1103 .remove = __exit_p(cmos_pnp_remove),
OGAWA Hirofumi004731b2010-01-08 14:43:11 -08001104 .shutdown = cmos_pnp_shutdown,
David Brownell7be2c7c2007-02-10 01:46:02 -08001105
1106 /* flag ensures resume() gets called, and stops syslog spam */
1107 .flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
Shuah Khana8a38082013-09-11 14:23:11 -07001108 .driver = {
1109 .pm = &cmos_pm_ops,
1110 },
David Brownell7be2c7c2007-02-10 01:46:02 -08001111};
1112
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001113#endif /* CONFIG_PNP */
David Brownell7be2c7c2007-02-10 01:46:02 -08001114
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001115#ifdef CONFIG_OF
1116static const struct of_device_id of_cmos_match[] = {
1117 {
1118 .compatible = "motorola,mc146818",
1119 },
1120 { },
1121};
1122MODULE_DEVICE_TABLE(of, of_cmos_match);
1123
1124static __init void cmos_of_init(struct platform_device *pdev)
1125{
1126 struct device_node *node = pdev->dev.of_node;
1127 struct rtc_time time;
1128 int ret;
1129 const __be32 *val;
1130
1131 if (!node)
1132 return;
1133
1134 val = of_get_property(node, "ctrl-reg", NULL);
1135 if (val)
1136 CMOS_WRITE(be32_to_cpup(val), RTC_CONTROL);
1137
1138 val = of_get_property(node, "freq-reg", NULL);
1139 if (val)
1140 CMOS_WRITE(be32_to_cpup(val), RTC_FREQ_SELECT);
1141
Arnd Bergmann5ab788d2016-05-30 20:57:50 +02001142 cmos_read_time(&pdev->dev, &time);
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001143 ret = rtc_valid_tm(&time);
1144 if (ret) {
1145 struct rtc_time def_time = {
1146 .tm_year = 1,
1147 .tm_mday = 1,
1148 };
Arnd Bergmann5ab788d2016-05-30 20:57:50 +02001149 cmos_set_time(&pdev->dev, &def_time);
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001150 }
1151}
1152#else
1153static inline void cmos_of_init(struct platform_device *pdev) {}
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001154#endif
David Brownell7be2c7c2007-02-10 01:46:02 -08001155/*----------------------------------------------------------------*/
1156
Marko Vrh41ac8df2007-05-08 00:34:09 -07001157/* Platform setup should have set up an RTC device, when PNP is
David Brownellbcd9b892007-04-01 23:49:47 -07001158 * unavailable ... this could happen even on (older) PCs.
David Brownell7be2c7c2007-02-10 01:46:02 -08001159 */
1160
1161static int __init cmos_platform_probe(struct platform_device *pdev)
1162{
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001163 struct resource *resource;
1164 int irq;
1165
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001166 cmos_of_init(pdev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001167 cmos_wake_setup(&pdev->dev);
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001168
1169 if (RTC_IOMAPPED)
1170 resource = platform_get_resource(pdev, IORESOURCE_IO, 0);
1171 else
1172 resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1173 irq = platform_get_irq(pdev, 0);
1174 if (irq < 0)
1175 irq = -1;
1176
1177 return cmos_do_probe(&pdev->dev, resource, irq);
David Brownell7be2c7c2007-02-10 01:46:02 -08001178}
1179
1180static int __exit cmos_platform_remove(struct platform_device *pdev)
1181{
1182 cmos_do_remove(&pdev->dev);
1183 return 0;
1184}
1185
1186static void cmos_platform_shutdown(struct platform_device *pdev)
1187{
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001188 struct device *dev = &pdev->dev;
1189 struct cmos_rtc *cmos = dev_get_drvdata(dev);
1190
Adrian Huang88b8d332015-07-06 12:19:12 +08001191 if (system_state == SYSTEM_POWER_OFF) {
1192 int retval = cmos_poweroff(dev);
1193
1194 if (cmos_aie_poweroff(dev) < 0 && !retval)
1195 return;
1196 }
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001197
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001198 cmos_do_shutdown(cmos->irq);
David Brownell7be2c7c2007-02-10 01:46:02 -08001199}
1200
Kay Sieversad28a072008-04-10 21:29:25 -07001201/* work with hotplug and coldplug */
1202MODULE_ALIAS("platform:rtc_cmos");
1203
David Brownell7be2c7c2007-02-10 01:46:02 -08001204static struct platform_driver cmos_platform_driver = {
1205 .remove = __exit_p(cmos_platform_remove),
1206 .shutdown = cmos_platform_shutdown,
1207 .driver = {
Geert Uytterhoevenc823a202014-01-23 15:55:11 -08001208 .name = driver_name,
Paul Fox2fb08e62011-01-12 17:00:07 -08001209#ifdef CONFIG_PM
1210 .pm = &cmos_pm_ops,
1211#endif
Sachin Kamatc8a60462013-02-21 16:44:28 -08001212 .of_match_table = of_match_ptr(of_cmos_match),
David Brownell7be2c7c2007-02-10 01:46:02 -08001213 }
1214};
1215
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001216#ifdef CONFIG_PNP
1217static bool pnp_driver_registered;
1218#endif
1219static bool platform_driver_registered;
1220
David Brownell7be2c7c2007-02-10 01:46:02 -08001221static int __init cmos_init(void)
1222{
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001223 int retval = 0;
1224
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001225#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001226 retval = pnp_register_driver(&cmos_pnp_driver);
1227 if (retval == 0)
1228 pnp_driver_registered = true;
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001229#endif
1230
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001231 if (!cmos_rtc.dev) {
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001232 retval = platform_driver_probe(&cmos_platform_driver,
1233 cmos_platform_probe);
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001234 if (retval == 0)
1235 platform_driver_registered = true;
1236 }
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001237
1238 if (retval == 0)
1239 return 0;
1240
1241#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001242 if (pnp_driver_registered)
1243 pnp_unregister_driver(&cmos_pnp_driver);
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001244#endif
1245 return retval;
David Brownell7be2c7c2007-02-10 01:46:02 -08001246}
1247module_init(cmos_init);
1248
1249static void __exit cmos_exit(void)
1250{
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001251#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001252 if (pnp_driver_registered)
1253 pnp_unregister_driver(&cmos_pnp_driver);
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001254#endif
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001255 if (platform_driver_registered)
1256 platform_driver_unregister(&cmos_platform_driver);
David Brownell7be2c7c2007-02-10 01:46:02 -08001257}
1258module_exit(cmos_exit);
1259
1260
David Brownell7be2c7c2007-02-10 01:46:02 -08001261MODULE_AUTHOR("David Brownell");
1262MODULE_DESCRIPTION("Driver for PC-style 'CMOS' RTCs");
1263MODULE_LICENSE("GPL");