blob: 8f7034ba7d9e30e5ef929ab0362186df249ed3be [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 */
46#include <asm-generic/rtc.h>
47
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
193 * that instead of the heuristic in get_rtc_time().
194 * That'll make Y3K compatility (year > 2070) easy!
195 */
196 get_rtc_time(t);
197 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 */
208 return set_rtc_time(t);
209}
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 */
223 t->time.tm_mday = -1;
224 t->time.tm_mon = -1;
225
226 spin_lock_irq(&rtc_lock);
227 t->time.tm_sec = CMOS_READ(RTC_SECONDS_ALARM);
228 t->time.tm_min = CMOS_READ(RTC_MINUTES_ALARM);
229 t->time.tm_hour = CMOS_READ(RTC_HOURS_ALARM);
230
231 if (cmos->day_alrm) {
Mark Lord615bb292007-11-03 22:04:03 -0400232 /* ignore upper bits on readback per ACPI spec */
233 t->time.tm_mday = CMOS_READ(cmos->day_alrm) & 0x3f;
David Brownell7be2c7c2007-02-10 01:46:02 -0800234 if (!t->time.tm_mday)
235 t->time.tm_mday = -1;
236
237 if (cmos->mon_alrm) {
238 t->time.tm_mon = CMOS_READ(cmos->mon_alrm);
239 if (!t->time.tm_mon)
240 t->time.tm_mon = -1;
241 }
242 }
243
244 rtc_control = CMOS_READ(RTC_CONTROL);
245 spin_unlock_irq(&rtc_lock);
246
Arnaud Patard3804a892010-04-29 11:58:44 +0200247 if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
248 if (((unsigned)t->time.tm_sec) < 0x60)
249 t->time.tm_sec = bcd2bin(t->time.tm_sec);
David Brownell7be2c7c2007-02-10 01:46:02 -0800250 else
Arnaud Patard3804a892010-04-29 11:58:44 +0200251 t->time.tm_sec = -1;
252 if (((unsigned)t->time.tm_min) < 0x60)
253 t->time.tm_min = bcd2bin(t->time.tm_min);
254 else
255 t->time.tm_min = -1;
256 if (((unsigned)t->time.tm_hour) < 0x24)
257 t->time.tm_hour = bcd2bin(t->time.tm_hour);
258 else
259 t->time.tm_hour = -1;
260
261 if (cmos->day_alrm) {
262 if (((unsigned)t->time.tm_mday) <= 0x31)
263 t->time.tm_mday = bcd2bin(t->time.tm_mday);
David Brownell7be2c7c2007-02-10 01:46:02 -0800264 else
Arnaud Patard3804a892010-04-29 11:58:44 +0200265 t->time.tm_mday = -1;
266
267 if (cmos->mon_alrm) {
268 if (((unsigned)t->time.tm_mon) <= 0x12)
269 t->time.tm_mon = bcd2bin(t->time.tm_mon)-1;
270 else
271 t->time.tm_mon = -1;
272 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800273 }
274 }
275 t->time.tm_year = -1;
276
277 t->enabled = !!(rtc_control & RTC_AIE);
278 t->pending = 0;
279
280 return 0;
281}
282
David Brownell7e2a31d2008-07-23 21:30:47 -0700283static void cmos_checkintr(struct cmos_rtc *cmos, unsigned char rtc_control)
284{
285 unsigned char rtc_intr;
286
287 /* NOTE after changing RTC_xIE bits we always read INTR_FLAGS;
288 * allegedly some older rtcs need that to handle irqs properly
289 */
290 rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
291
292 if (is_hpet_enabled())
293 return;
294
295 rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
296 if (is_intr(rtc_intr))
297 rtc_update_irq(cmos->rtc, 1, rtc_intr);
298}
299
300static void cmos_irq_enable(struct cmos_rtc *cmos, unsigned char mask)
301{
302 unsigned char rtc_control;
303
304 /* flush any pending IRQ status, notably for update irqs,
305 * before we enable new IRQs
306 */
307 rtc_control = CMOS_READ(RTC_CONTROL);
308 cmos_checkintr(cmos, rtc_control);
309
310 rtc_control |= mask;
311 CMOS_WRITE(rtc_control, RTC_CONTROL);
312 hpet_set_rtc_irq_bit(mask);
313
314 cmos_checkintr(cmos, rtc_control);
315}
316
317static void cmos_irq_disable(struct cmos_rtc *cmos, unsigned char mask)
318{
319 unsigned char rtc_control;
320
321 rtc_control = CMOS_READ(RTC_CONTROL);
322 rtc_control &= ~mask;
323 CMOS_WRITE(rtc_control, RTC_CONTROL);
324 hpet_mask_rtc_irq_bit(mask);
325
326 cmos_checkintr(cmos, rtc_control);
327}
328
David Brownell7be2c7c2007-02-10 01:46:02 -0800329static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
330{
331 struct cmos_rtc *cmos = dev_get_drvdata(dev);
Sachin Kamat5e8599d2013-07-03 15:05:45 -0700332 unsigned char mon, mday, hrs, min, sec, rtc_control;
David Brownell7be2c7c2007-02-10 01:46:02 -0800333
334 if (!is_valid_irq(cmos->irq))
335 return -EIO;
336
Zhao Yakui2b653e02008-04-15 14:34:29 -0700337 mon = t->time.tm_mon + 1;
David Brownell7be2c7c2007-02-10 01:46:02 -0800338 mday = t->time.tm_mday;
David Brownell7be2c7c2007-02-10 01:46:02 -0800339 hrs = t->time.tm_hour;
David Brownell7be2c7c2007-02-10 01:46:02 -0800340 min = t->time.tm_min;
David Brownell7be2c7c2007-02-10 01:46:02 -0800341 sec = t->time.tm_sec;
Arnaud Patard3804a892010-04-29 11:58:44 +0200342
343 rtc_control = CMOS_READ(RTC_CONTROL);
344 if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
345 /* Writing 0xff means "don't care" or "match all". */
346 mon = (mon <= 12) ? bin2bcd(mon) : 0xff;
347 mday = (mday >= 1 && mday <= 31) ? bin2bcd(mday) : 0xff;
348 hrs = (hrs < 24) ? bin2bcd(hrs) : 0xff;
349 min = (min < 60) ? bin2bcd(min) : 0xff;
350 sec = (sec < 60) ? bin2bcd(sec) : 0xff;
351 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800352
353 spin_lock_irq(&rtc_lock);
354
355 /* next rtc irq must not be from previous alarm setting */
David Brownell7e2a31d2008-07-23 21:30:47 -0700356 cmos_irq_disable(cmos, RTC_AIE);
David Brownell7be2c7c2007-02-10 01:46:02 -0800357
358 /* update alarm */
359 CMOS_WRITE(hrs, RTC_HOURS_ALARM);
360 CMOS_WRITE(min, RTC_MINUTES_ALARM);
361 CMOS_WRITE(sec, RTC_SECONDS_ALARM);
362
363 /* the system may support an "enhanced" alarm */
364 if (cmos->day_alrm) {
365 CMOS_WRITE(mday, cmos->day_alrm);
366 if (cmos->mon_alrm)
367 CMOS_WRITE(mon, cmos->mon_alrm);
368 }
369
David Brownell35d3fdd2008-07-23 21:30:43 -0700370 /* FIXME the HPET alarm glue currently ignores day_alrm
371 * and mon_alrm ...
372 */
373 hpet_set_alarm_time(t->time.tm_hour, t->time.tm_min, t->time.tm_sec);
374
David Brownell7e2a31d2008-07-23 21:30:47 -0700375 if (t->enabled)
376 cmos_irq_enable(cmos, RTC_AIE);
David Brownell7be2c7c2007-02-10 01:46:02 -0800377
378 spin_unlock_irq(&rtc_lock);
379
Adrian Huang88b8d332015-07-06 12:19:12 +0800380 cmos->alarm_expires = rtc_tm_to_time64(&t->time);
381
David Brownell7be2c7c2007-02-10 01:46:02 -0800382 return 0;
383}
384
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800385static int cmos_alarm_irq_enable(struct device *dev, unsigned int enabled)
David Brownell7be2c7c2007-02-10 01:46:02 -0800386{
387 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownell7be2c7c2007-02-10 01:46:02 -0800388 unsigned long flags;
389
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800390 if (!is_valid_irq(cmos->irq))
391 return -EINVAL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800392
393 spin_lock_irqsave(&rtc_lock, flags);
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800394
395 if (enabled)
David Brownell7e2a31d2008-07-23 21:30:47 -0700396 cmos_irq_enable(cmos, RTC_AIE);
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800397 else
398 cmos_irq_disable(cmos, RTC_AIE);
399
David Brownell7be2c7c2007-02-10 01:46:02 -0800400 spin_unlock_irqrestore(&rtc_lock, flags);
401 return 0;
402}
403
David Brownell7be2c7c2007-02-10 01:46:02 -0800404#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
405
406static int cmos_procfs(struct device *dev, struct seq_file *seq)
407{
408 struct cmos_rtc *cmos = dev_get_drvdata(dev);
409 unsigned char rtc_control, valid;
410
411 spin_lock_irq(&rtc_lock);
412 rtc_control = CMOS_READ(RTC_CONTROL);
413 valid = CMOS_READ(RTC_VALID);
414 spin_unlock_irq(&rtc_lock);
415
416 /* NOTE: at least ICH6 reports battery status using a different
417 * (non-RTC) bit; and SQWE is ignored on many current systems.
418 */
Joe Perches4395eb12015-04-15 16:17:51 -0700419 seq_printf(seq,
420 "periodic_IRQ\t: %s\n"
421 "update_IRQ\t: %s\n"
422 "HPET_emulated\t: %s\n"
423 // "square_wave\t: %s\n"
424 "BCD\t\t: %s\n"
425 "DST_enable\t: %s\n"
426 "periodic_freq\t: %d\n"
427 "batt_status\t: %s\n",
428 (rtc_control & RTC_PIE) ? "yes" : "no",
429 (rtc_control & RTC_UIE) ? "yes" : "no",
430 is_hpet_enabled() ? "yes" : "no",
431 // (rtc_control & RTC_SQWE) ? "yes" : "no",
432 (rtc_control & RTC_DM_BINARY) ? "no" : "yes",
433 (rtc_control & RTC_DST_EN) ? "yes" : "no",
434 cmos->rtc->irq_freq,
435 (valid & RTC_VRT) ? "okay" : "dead");
436
437 return 0;
David Brownell7be2c7c2007-02-10 01:46:02 -0800438}
439
440#else
441#define cmos_procfs NULL
442#endif
443
444static const struct rtc_class_ops cmos_rtc_ops = {
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800445 .read_time = cmos_read_time,
446 .set_time = cmos_set_time,
447 .read_alarm = cmos_read_alarm,
448 .set_alarm = cmos_set_alarm,
449 .proc = cmos_procfs,
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800450 .alarm_irq_enable = cmos_alarm_irq_enable,
David Brownell7be2c7c2007-02-10 01:46:02 -0800451};
452
453/*----------------------------------------------------------------*/
454
David Brownelle07e2322008-02-06 01:38:43 -0800455/*
456 * All these chips have at least 64 bytes of address space, shared by
457 * RTC registers and NVRAM. Most of those bytes of NVRAM are used
458 * by boot firmware. Modern chips have 128 or 256 bytes.
459 */
460
461#define NVRAM_OFFSET (RTC_REG_D + 1)
462
463static ssize_t
Chris Wright2c3c8be2010-05-12 18:28:57 -0700464cmos_nvram_read(struct file *filp, struct kobject *kobj,
465 struct bin_attribute *attr,
David Brownelle07e2322008-02-06 01:38:43 -0800466 char *buf, loff_t off, size_t count)
467{
468 int retval;
469
David Brownellc8fc40c2008-10-18 20:27:47 -0700470 off += NVRAM_OFFSET;
David Brownelle07e2322008-02-06 01:38:43 -0800471 spin_lock_irq(&rtc_lock);
David Brownellc8fc40c2008-10-18 20:27:47 -0700472 for (retval = 0; count; count--, off++, retval++) {
473 if (off < 128)
474 *buf++ = CMOS_READ(off);
475 else if (can_bank2)
476 *buf++ = cmos_read_bank2(off);
477 else
478 break;
479 }
David Brownelle07e2322008-02-06 01:38:43 -0800480 spin_unlock_irq(&rtc_lock);
481
482 return retval;
483}
484
485static ssize_t
Chris Wright2c3c8be2010-05-12 18:28:57 -0700486cmos_nvram_write(struct file *filp, struct kobject *kobj,
487 struct bin_attribute *attr,
David Brownelle07e2322008-02-06 01:38:43 -0800488 char *buf, loff_t off, size_t count)
489{
490 struct cmos_rtc *cmos;
491 int retval;
492
493 cmos = dev_get_drvdata(container_of(kobj, struct device, kobj));
David Brownelle07e2322008-02-06 01:38:43 -0800494
495 /* NOTE: on at least PCs and Ataris, the boot firmware uses a
496 * checksum on part of the NVRAM data. That's currently ignored
497 * here. If userspace is smart enough to know what fields of
498 * NVRAM to update, updating checksums is also part of its job.
499 */
David Brownellc8fc40c2008-10-18 20:27:47 -0700500 off += NVRAM_OFFSET;
David Brownelle07e2322008-02-06 01:38:43 -0800501 spin_lock_irq(&rtc_lock);
David Brownellc8fc40c2008-10-18 20:27:47 -0700502 for (retval = 0; count; count--, off++, retval++) {
David Brownelle07e2322008-02-06 01:38:43 -0800503 /* don't trash RTC registers */
504 if (off == cmos->day_alrm
505 || off == cmos->mon_alrm
506 || off == cmos->century)
507 buf++;
David Brownellc8fc40c2008-10-18 20:27:47 -0700508 else if (off < 128)
David Brownelle07e2322008-02-06 01:38:43 -0800509 CMOS_WRITE(*buf++, off);
David Brownellc8fc40c2008-10-18 20:27:47 -0700510 else if (can_bank2)
511 cmos_write_bank2(*buf++, off);
512 else
513 break;
David Brownelle07e2322008-02-06 01:38:43 -0800514 }
515 spin_unlock_irq(&rtc_lock);
516
517 return retval;
518}
519
520static struct bin_attribute nvram = {
521 .attr = {
522 .name = "nvram",
523 .mode = S_IRUGO | S_IWUSR,
David Brownelle07e2322008-02-06 01:38:43 -0800524 },
525
526 .read = cmos_nvram_read,
527 .write = cmos_nvram_write,
528 /* size gets set up later */
529};
530
531/*----------------------------------------------------------------*/
532
David Brownell7be2c7c2007-02-10 01:46:02 -0800533static struct cmos_rtc cmos_rtc;
534
535static irqreturn_t cmos_interrupt(int irq, void *p)
536{
537 u8 irqstat;
David Brownell8a0bdfd2008-02-06 01:38:45 -0800538 u8 rtc_control;
David Brownell7be2c7c2007-02-10 01:46:02 -0800539
540 spin_lock(&rtc_lock);
David Brownell35d3fdd2008-07-23 21:30:43 -0700541
542 /* When the HPET interrupt handler calls us, the interrupt
543 * status is passed as arg1 instead of the irq number. But
544 * always clear irq status, even when HPET is in the way.
545 *
546 * Note that HPET and RTC are almost certainly out of phase,
547 * giving different IRQ status ...
Bernhard Walle9d8af782008-02-06 01:38:52 -0800548 */
David Brownell35d3fdd2008-07-23 21:30:43 -0700549 irqstat = CMOS_READ(RTC_INTR_FLAGS);
550 rtc_control = CMOS_READ(RTC_CONTROL);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800551 if (is_hpet_enabled())
552 irqstat = (unsigned long)irq & 0xF0;
Derek Basehore998a0602013-07-03 15:07:54 -0700553
554 /* If we were suspended, RTC_CONTROL may not be accurate since the
555 * bios may have cleared it.
556 */
557 if (!cmos_rtc.suspend_ctrl)
558 irqstat &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
559 else
560 irqstat &= (cmos_rtc.suspend_ctrl & RTC_IRQMASK) | RTC_IRQF;
David Brownell8a0bdfd2008-02-06 01:38:45 -0800561
562 /* All Linux RTC alarms should be treated as if they were oneshot.
563 * Similar code may be needed in system wakeup paths, in case the
564 * alarm woke the system.
565 */
566 if (irqstat & RTC_AIE) {
Derek Basehore998a0602013-07-03 15:07:54 -0700567 cmos_rtc.suspend_ctrl &= ~RTC_AIE;
David Brownell8a0bdfd2008-02-06 01:38:45 -0800568 rtc_control &= ~RTC_AIE;
569 CMOS_WRITE(rtc_control, RTC_CONTROL);
David Brownell35d3fdd2008-07-23 21:30:43 -0700570 hpet_mask_rtc_irq_bit(RTC_AIE);
David Brownell8a0bdfd2008-02-06 01:38:45 -0800571 CMOS_READ(RTC_INTR_FLAGS);
572 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800573 spin_unlock(&rtc_lock);
574
David Brownellbcd9b892007-04-01 23:49:47 -0700575 if (is_intr(irqstat)) {
David Brownell7be2c7c2007-02-10 01:46:02 -0800576 rtc_update_irq(p, 1, irqstat);
577 return IRQ_HANDLED;
578 } else
579 return IRQ_NONE;
580}
581
Marko Vrh41ac8df2007-05-08 00:34:09 -0700582#ifdef CONFIG_PNP
David Brownell7be2c7c2007-02-10 01:46:02 -0800583#define INITSECTION
584
585#else
David Brownell7be2c7c2007-02-10 01:46:02 -0800586#define INITSECTION __init
587#endif
588
589static int INITSECTION
590cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
591{
Jingoo Han97a92e72013-11-12 15:10:38 -0800592 struct cmos_rtc_board_info *info = dev_get_platdata(dev);
David Brownell7be2c7c2007-02-10 01:46:02 -0800593 int retval = 0;
594 unsigned char rtc_control;
David Brownelle07e2322008-02-06 01:38:43 -0800595 unsigned address_space;
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700596 u32 flags = 0;
David Brownell7be2c7c2007-02-10 01:46:02 -0800597
598 /* there can be only one ... */
599 if (cmos_rtc.dev)
600 return -EBUSY;
601
602 if (!ports)
603 return -ENODEV;
604
David Brownell05440df2007-10-16 01:28:21 -0700605 /* Claim I/O ports ASAP, minimizing conflict with legacy driver.
606 *
607 * REVISIT non-x86 systems may instead use memory space resources
608 * (needing ioremap etc), not i/o space resources like this ...
609 */
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700610 if (RTC_IOMAPPED)
611 ports = request_region(ports->start, resource_size(ports),
612 driver_name);
613 else
614 ports = request_mem_region(ports->start, resource_size(ports),
615 driver_name);
David Brownell05440df2007-10-16 01:28:21 -0700616 if (!ports) {
617 dev_dbg(dev, "i/o registers already in use\n");
618 return -EBUSY;
619 }
620
David Brownell7be2c7c2007-02-10 01:46:02 -0800621 cmos_rtc.irq = rtc_irq;
622 cmos_rtc.iomem = ports;
623
David Brownelle07e2322008-02-06 01:38:43 -0800624 /* Heuristic to deduce NVRAM size ... do what the legacy NVRAM
625 * driver did, but don't reject unknown configs. Old hardware
David Brownellc8fc40c2008-10-18 20:27:47 -0700626 * won't address 128 bytes. Newer chips have multiple banks,
627 * though they may not be listed in one I/O resource.
David Brownelle07e2322008-02-06 01:38:43 -0800628 */
629#if defined(CONFIG_ATARI)
630 address_space = 64;
Wu Zhangjin95abd0d2009-11-05 09:21:54 +0800631#elif defined(__i386__) || defined(__x86_64__) || defined(__arm__) \
Srikanth Krishnakar8cb7c712010-10-14 04:03:35 +0000632 || defined(__sparc__) || defined(__mips__) \
633 || defined(__powerpc__)
David Brownelle07e2322008-02-06 01:38:43 -0800634 address_space = 128;
635#else
636#warning Assuming 128 bytes of RTC+NVRAM address space, not 64 bytes.
637 address_space = 128;
638#endif
David Brownellc8fc40c2008-10-18 20:27:47 -0700639 if (can_bank2 && ports->end > (ports->start + 1))
640 address_space = 256;
David Brownelle07e2322008-02-06 01:38:43 -0800641
David Brownell87ac84f2007-05-08 00:34:00 -0700642 /* For ACPI systems extension info comes from the FADT. On others,
643 * board specific setup provides it as appropriate. Systems where
644 * the alarm IRQ isn't automatically a wakeup IRQ (like ACPI, and
645 * some almost-clones) can provide hooks to make that behave.
David Brownelle07e2322008-02-06 01:38:43 -0800646 *
647 * Note that ACPI doesn't preclude putting these registers into
648 * "extended" areas of the chip, including some that we won't yet
649 * expect CMOS_READ and friends to handle.
David Brownell7be2c7c2007-02-10 01:46:02 -0800650 */
651 if (info) {
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700652 if (info->flags)
653 flags = info->flags;
654 if (info->address_space)
655 address_space = info->address_space;
656
David Brownelle07e2322008-02-06 01:38:43 -0800657 if (info->rtc_day_alarm && info->rtc_day_alarm < 128)
658 cmos_rtc.day_alrm = info->rtc_day_alarm;
659 if (info->rtc_mon_alarm && info->rtc_mon_alarm < 128)
660 cmos_rtc.mon_alrm = info->rtc_mon_alarm;
661 if (info->rtc_century && info->rtc_century < 128)
662 cmos_rtc.century = info->rtc_century;
David Brownell87ac84f2007-05-08 00:34:00 -0700663
664 if (info->wake_on && info->wake_off) {
665 cmos_rtc.wake_on = info->wake_on;
666 cmos_rtc.wake_off = info->wake_off;
667 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800668 }
669
Dan Carpenter6ba8bcd2010-05-24 14:33:49 -0700670 cmos_rtc.dev = dev;
671 dev_set_drvdata(dev, &cmos_rtc);
672
David Brownell7be2c7c2007-02-10 01:46:02 -0800673 cmos_rtc.rtc = rtc_device_register(driver_name, dev,
674 &cmos_rtc_ops, THIS_MODULE);
David Brownell05440df2007-10-16 01:28:21 -0700675 if (IS_ERR(cmos_rtc.rtc)) {
676 retval = PTR_ERR(cmos_rtc.rtc);
677 goto cleanup0;
678 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800679
Kay Sieversd4afc762009-01-06 14:42:11 -0800680 rename_region(ports, dev_name(&cmos_rtc.rtc->dev));
David Brownell7be2c7c2007-02-10 01:46:02 -0800681
682 spin_lock_irq(&rtc_lock);
683
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700684 if (!(flags & CMOS_RTC_FLAGS_NOFREQ)) {
685 /* force periodic irq to CMOS reset default of 1024Hz;
686 *
687 * REVISIT it's been reported that at least one x86_64 ALI
688 * mobo doesn't use 32KHz here ... for portability we might
689 * need to do something about other clock frequencies.
690 */
691 cmos_rtc.rtc->irq_freq = 1024;
692 hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq);
693 CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
694 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800695
David Brownell7e2a31d2008-07-23 21:30:47 -0700696 /* disable irqs */
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700697 if (is_valid_irq(rtc_irq))
698 cmos_irq_disable(&cmos_rtc, RTC_PIE | RTC_AIE | RTC_UIE);
David Brownell35d3fdd2008-07-23 21:30:43 -0700699
David Brownell7e2a31d2008-07-23 21:30:47 -0700700 rtc_control = CMOS_READ(RTC_CONTROL);
David Brownell7be2c7c2007-02-10 01:46:02 -0800701
702 spin_unlock_irq(&rtc_lock);
703
Arnaud Patard3804a892010-04-29 11:58:44 +0200704 /* FIXME:
David Brownell7be2c7c2007-02-10 01:46:02 -0800705 * <asm-generic/rtc.h> doesn't know 12-hour mode either.
706 */
Sachin Kamat5e8599d2013-07-03 15:05:45 -0700707 if (is_valid_irq(rtc_irq) && !(rtc_control & RTC_24H)) {
Arnaud Patard3804a892010-04-29 11:58:44 +0200708 dev_warn(dev, "only 24-hr supported\n");
David Brownell7be2c7c2007-02-10 01:46:02 -0800709 retval = -ENXIO;
710 goto cleanup1;
711 }
712
Bernhard Walle9d8af782008-02-06 01:38:52 -0800713 if (is_valid_irq(rtc_irq)) {
714 irq_handler_t rtc_cmos_int_handler;
715
716 if (is_hpet_enabled()) {
Bernhard Walle9d8af782008-02-06 01:38:52 -0800717 rtc_cmos_int_handler = hpet_rtc_interrupt;
Andrew Morton24b34472014-01-23 15:55:15 -0800718 retval = hpet_register_irq_handler(cmos_interrupt);
719 if (retval) {
Jingoo Hanee443352013-02-21 16:45:34 -0800720 dev_warn(dev, "hpet_register_irq_handler "
Bernhard Walle9d8af782008-02-06 01:38:52 -0800721 " failed in rtc_init().");
722 goto cleanup1;
723 }
724 } else
725 rtc_cmos_int_handler = cmos_interrupt;
726
727 retval = request_irq(rtc_irq, rtc_cmos_int_handler,
Yong Zhang2f6e5f92012-03-23 15:02:34 -0700728 0, dev_name(&cmos_rtc.rtc->dev),
David Brownellab6a2d72007-05-08 00:33:30 -0700729 cmos_rtc.rtc);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800730 if (retval < 0) {
731 dev_dbg(dev, "IRQ %d is already in use\n", rtc_irq);
732 goto cleanup1;
733 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800734 }
Bernhard Walle9d8af782008-02-06 01:38:52 -0800735 hpet_rtc_timer_init();
David Brownell7be2c7c2007-02-10 01:46:02 -0800736
David Brownelle07e2322008-02-06 01:38:43 -0800737 /* export at least the first block of NVRAM */
738 nvram.size = address_space - NVRAM_OFFSET;
739 retval = sysfs_create_bin_file(&dev->kobj, &nvram);
740 if (retval < 0) {
741 dev_dbg(dev, "can't create nvram file? %d\n", retval);
742 goto cleanup2;
743 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800744
Jingoo Hanee443352013-02-21 16:45:34 -0800745 dev_info(dev, "%s%s, %zd bytes nvram%s\n",
Krzysztof Halasa6d029b62009-04-21 12:24:49 -0700746 !is_valid_irq(rtc_irq) ? "no alarms" :
747 cmos_rtc.mon_alrm ? "alarms up to one year" :
748 cmos_rtc.day_alrm ? "alarms up to one month" :
749 "alarms up to one day",
750 cmos_rtc.century ? ", y3k" : "",
751 nvram.size,
752 is_hpet_enabled() ? ", hpet irqs" : "");
David Brownell7be2c7c2007-02-10 01:46:02 -0800753
754 return 0;
755
David Brownelle07e2322008-02-06 01:38:43 -0800756cleanup2:
757 if (is_valid_irq(rtc_irq))
758 free_irq(rtc_irq, cmos_rtc.rtc);
David Brownell7be2c7c2007-02-10 01:46:02 -0800759cleanup1:
David Brownell05440df2007-10-16 01:28:21 -0700760 cmos_rtc.dev = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800761 rtc_device_unregister(cmos_rtc.rtc);
David Brownell05440df2007-10-16 01:28:21 -0700762cleanup0:
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700763 if (RTC_IOMAPPED)
764 release_region(ports->start, resource_size(ports));
765 else
766 release_mem_region(ports->start, resource_size(ports));
David Brownell7be2c7c2007-02-10 01:46:02 -0800767 return retval;
768}
769
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700770static void cmos_do_shutdown(int rtc_irq)
David Brownell7be2c7c2007-02-10 01:46:02 -0800771{
David Brownell7be2c7c2007-02-10 01:46:02 -0800772 spin_lock_irq(&rtc_lock);
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700773 if (is_valid_irq(rtc_irq))
774 cmos_irq_disable(&cmos_rtc, RTC_IRQMASK);
David Brownell7be2c7c2007-02-10 01:46:02 -0800775 spin_unlock_irq(&rtc_lock);
776}
777
778static void __exit cmos_do_remove(struct device *dev)
779{
780 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownell05440df2007-10-16 01:28:21 -0700781 struct resource *ports;
David Brownell7be2c7c2007-02-10 01:46:02 -0800782
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700783 cmos_do_shutdown(cmos->irq);
David Brownell7be2c7c2007-02-10 01:46:02 -0800784
David Brownelle07e2322008-02-06 01:38:43 -0800785 sysfs_remove_bin_file(&dev->kobj, &nvram);
786
Bernhard Walle9d8af782008-02-06 01:38:52 -0800787 if (is_valid_irq(cmos->irq)) {
David Brownell05440df2007-10-16 01:28:21 -0700788 free_irq(cmos->irq, cmos->rtc);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800789 hpet_unregister_irq_handler(cmos_interrupt);
790 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800791
David Brownell05440df2007-10-16 01:28:21 -0700792 rtc_device_unregister(cmos->rtc);
793 cmos->rtc = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800794
David Brownell05440df2007-10-16 01:28:21 -0700795 ports = cmos->iomem;
Maciej W. Rozycki31632db2014-06-06 14:35:49 -0700796 if (RTC_IOMAPPED)
797 release_region(ports->start, resource_size(ports));
798 else
799 release_mem_region(ports->start, resource_size(ports));
David Brownell05440df2007-10-16 01:28:21 -0700800 cmos->iomem = NULL;
801
802 cmos->dev = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800803}
804
Adrian Huang88b8d332015-07-06 12:19:12 +0800805static int cmos_aie_poweroff(struct device *dev)
806{
807 struct cmos_rtc *cmos = dev_get_drvdata(dev);
808 struct rtc_time now;
809 time64_t t_now;
810 int retval = 0;
811 unsigned char rtc_control;
812
813 if (!cmos->alarm_expires)
814 return -EINVAL;
815
816 spin_lock_irq(&rtc_lock);
817 rtc_control = CMOS_READ(RTC_CONTROL);
818 spin_unlock_irq(&rtc_lock);
819
820 /* We only care about the situation where AIE is disabled. */
821 if (rtc_control & RTC_AIE)
822 return -EBUSY;
823
824 cmos_read_time(dev, &now);
825 t_now = rtc_tm_to_time64(&now);
826
827 /*
828 * When enabling "RTC wake-up" in BIOS setup, the machine reboots
829 * automatically right after shutdown on some buggy boxes.
830 * This automatic rebooting issue won't happen when the alarm
831 * time is larger than now+1 seconds.
832 *
833 * If the alarm time is equal to now+1 seconds, the issue can be
834 * prevented by cancelling the alarm.
835 */
836 if (cmos->alarm_expires == t_now + 1) {
837 struct rtc_wkalrm alarm;
838
839 /* Cancel the AIE timer by configuring the past time. */
840 rtc_time64_to_tm(t_now - 1, &alarm.time);
841 alarm.enabled = 0;
842 retval = cmos_set_alarm(dev, &alarm);
843 } else if (cmos->alarm_expires > t_now + 1) {
844 retval = -EBUSY;
845 }
846
847 return retval;
848}
849
Daniel Glöcknera882b142014-10-13 15:53:16 -0700850#ifdef CONFIG_PM
David Brownell7be2c7c2007-02-10 01:46:02 -0800851
Paul Fox2fb08e62011-01-12 17:00:07 -0800852static int cmos_suspend(struct device *dev)
David Brownell7be2c7c2007-02-10 01:46:02 -0800853{
854 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownellbcd9b892007-04-01 23:49:47 -0700855 unsigned char tmp;
David Brownell7be2c7c2007-02-10 01:46:02 -0800856
857 /* only the alarm might be a wakeup event source */
858 spin_lock_irq(&rtc_lock);
859 cmos->suspend_ctrl = tmp = CMOS_READ(RTC_CONTROL);
860 if (tmp & (RTC_PIE|RTC_AIE|RTC_UIE)) {
David Brownell35d3fdd2008-07-23 21:30:43 -0700861 unsigned char mask;
David Brownellbcd9b892007-04-01 23:49:47 -0700862
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700863 if (device_may_wakeup(dev))
David Brownell35d3fdd2008-07-23 21:30:43 -0700864 mask = RTC_IRQMASK & ~RTC_AIE;
David Brownell7be2c7c2007-02-10 01:46:02 -0800865 else
David Brownell35d3fdd2008-07-23 21:30:43 -0700866 mask = RTC_IRQMASK;
867 tmp &= ~mask;
David Brownell7be2c7c2007-02-10 01:46:02 -0800868 CMOS_WRITE(tmp, RTC_CONTROL);
Derek Basehoree0057152013-04-29 16:20:23 -0700869 hpet_mask_rtc_irq_bit(mask);
David Brownell35d3fdd2008-07-23 21:30:43 -0700870
David Brownell7e2a31d2008-07-23 21:30:47 -0700871 cmos_checkintr(cmos, tmp);
David Brownellbcd9b892007-04-01 23:49:47 -0700872 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800873 spin_unlock_irq(&rtc_lock);
874
David Brownell87ac84f2007-05-08 00:34:00 -0700875 if (tmp & RTC_AIE) {
876 cmos->enabled_wake = 1;
877 if (cmos->wake_on)
878 cmos->wake_on(dev);
879 else
880 enable_irq_wake(cmos->irq);
881 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800882
Jingoo Hanee443352013-02-21 16:45:34 -0800883 dev_dbg(dev, "suspend%s, ctrl %02x\n",
David Brownell7be2c7c2007-02-10 01:46:02 -0800884 (tmp & RTC_AIE) ? ", alarm may wake" : "",
885 tmp);
886
887 return 0;
888}
889
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700890/* We want RTC alarms to wake us from e.g. ACPI G2/S5 "soft off", even
891 * after a detour through G3 "mechanical off", although the ACPI spec
892 * says wakeup should only work from G1/S4 "hibernate". To most users,
893 * distinctions between S4 and S5 are pointless. So when the hardware
894 * allows, don't draw that distinction.
895 */
896static inline int cmos_poweroff(struct device *dev)
897{
Paul Fox2fb08e62011-01-12 17:00:07 -0800898 return cmos_suspend(dev);
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700899}
900
Daniel Glöcknera882b142014-10-13 15:53:16 -0700901#ifdef CONFIG_PM_SLEEP
902
David Brownell7be2c7c2007-02-10 01:46:02 -0800903static int cmos_resume(struct device *dev)
904{
905 struct cmos_rtc *cmos = dev_get_drvdata(dev);
Derek Basehore998a0602013-07-03 15:07:54 -0700906 unsigned char tmp;
David Brownell7be2c7c2007-02-10 01:46:02 -0800907
Derek Basehore998a0602013-07-03 15:07:54 -0700908 if (cmos->enabled_wake) {
909 if (cmos->wake_off)
910 cmos->wake_off(dev);
911 else
912 disable_irq_wake(cmos->irq);
913 cmos->enabled_wake = 0;
914 }
915
916 spin_lock_irq(&rtc_lock);
917 tmp = cmos->suspend_ctrl;
918 cmos->suspend_ctrl = 0;
David Brownell7be2c7c2007-02-10 01:46:02 -0800919 /* re-enable any irqs previously active */
David Brownell35d3fdd2008-07-23 21:30:43 -0700920 if (tmp & RTC_IRQMASK) {
921 unsigned char mask;
David Brownell7be2c7c2007-02-10 01:46:02 -0800922
Derek Basehoreebf8d6c2013-06-12 14:04:45 -0700923 if (device_may_wakeup(dev))
924 hpet_rtc_timer_init();
925
David Brownell35d3fdd2008-07-23 21:30:43 -0700926 do {
927 CMOS_WRITE(tmp, RTC_CONTROL);
928 hpet_set_rtc_irq_bit(tmp & RTC_IRQMASK);
929
930 mask = CMOS_READ(RTC_INTR_FLAGS);
931 mask &= (tmp & RTC_IRQMASK) | RTC_IRQF;
David Brownell7e2a31d2008-07-23 21:30:47 -0700932 if (!is_hpet_enabled() || !is_intr(mask))
David Brownell35d3fdd2008-07-23 21:30:43 -0700933 break;
934
935 /* force one-shot behavior if HPET blocked
936 * the wake alarm's irq
937 */
938 rtc_update_irq(cmos->rtc, 1, mask);
939 tmp &= ~RTC_AIE;
940 hpet_mask_rtc_irq_bit(RTC_AIE);
941 } while (mask & RTC_AIE);
David Brownell7be2c7c2007-02-10 01:46:02 -0800942 }
Derek Basehore998a0602013-07-03 15:07:54 -0700943 spin_unlock_irq(&rtc_lock);
David Brownell7be2c7c2007-02-10 01:46:02 -0800944
Jingoo Hanee443352013-02-21 16:45:34 -0800945 dev_dbg(dev, "resume, ctrl %02x\n", tmp);
David Brownell7be2c7c2007-02-10 01:46:02 -0800946
947 return 0;
948}
949
Daniel Glöcknera882b142014-10-13 15:53:16 -0700950#endif
David Brownell7be2c7c2007-02-10 01:46:02 -0800951#else
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700952
953static inline int cmos_poweroff(struct device *dev)
954{
955 return -ENOSYS;
956}
957
David Brownell7be2c7c2007-02-10 01:46:02 -0800958#endif
959
Mika Westerbergb5ada462014-04-03 14:50:05 -0700960static SIMPLE_DEV_PM_OPS(cmos_pm_ops, cmos_suspend, cmos_resume);
961
David Brownell7be2c7c2007-02-10 01:46:02 -0800962/*----------------------------------------------------------------*/
963
David Brownelle07e2322008-02-06 01:38:43 -0800964/* On non-x86 systems, a "CMOS" RTC lives most naturally on platform_bus.
965 * ACPI systems always list these as PNPACPI devices, and pre-ACPI PCs
966 * probably list them in similar PNPBIOS tables; so PNP is more common.
967 *
968 * We don't use legacy "poke at the hardware" probing. Ancient PCs that
969 * predate even PNPBIOS should set up platform_bus devices.
David Brownell7be2c7c2007-02-10 01:46:02 -0800970 */
971
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600972#ifdef CONFIG_ACPI
973
974#include <linux/acpi.h>
975
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600976static u32 rtc_handler(void *context)
977{
Daniel Drakeb2201e52012-05-18 22:59:41 +0200978 struct device *dev = context;
979
980 pm_wakeup_event(dev, 0);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600981 acpi_clear_event(ACPI_EVENT_RTC);
982 acpi_disable_event(ACPI_EVENT_RTC, 0);
983 return ACPI_INTERRUPT_HANDLED;
984}
985
Daniel Drakeb2201e52012-05-18 22:59:41 +0200986static inline void rtc_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600987{
Daniel Drakeb2201e52012-05-18 22:59:41 +0200988 acpi_install_fixed_event_handler(ACPI_EVENT_RTC, rtc_handler, dev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600989 /*
990 * After the RTC handler is installed, the Fixed_RTC event should
991 * be disabled. Only when the RTC alarm is set will it be enabled.
992 */
993 acpi_clear_event(ACPI_EVENT_RTC);
994 acpi_disable_event(ACPI_EVENT_RTC, 0);
995}
996
997static void rtc_wake_on(struct device *dev)
998{
999 acpi_clear_event(ACPI_EVENT_RTC);
1000 acpi_enable_event(ACPI_EVENT_RTC, 0);
1001}
1002
1003static void rtc_wake_off(struct device *dev)
1004{
1005 acpi_disable_event(ACPI_EVENT_RTC, 0);
1006}
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001007
1008/* Every ACPI platform has a mc146818 compatible "cmos rtc". Here we find
1009 * its device node and pass extra config data. This helps its driver use
1010 * capabilities that the now-obsolete mc146818 didn't have, and informs it
1011 * that this board's RTC is wakeup-capable (per ACPI spec).
1012 */
1013static struct cmos_rtc_board_info acpi_rtc_info;
1014
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -08001015static void cmos_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001016{
1017 if (acpi_disabled)
1018 return;
1019
Daniel Drakeb2201e52012-05-18 22:59:41 +02001020 rtc_wake_setup(dev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001021 acpi_rtc_info.wake_on = rtc_wake_on;
1022 acpi_rtc_info.wake_off = rtc_wake_off;
1023
1024 /* workaround bug in some ACPI tables */
1025 if (acpi_gbl_FADT.month_alarm && !acpi_gbl_FADT.day_alarm) {
1026 dev_dbg(dev, "bogus FADT month_alarm (%d)\n",
1027 acpi_gbl_FADT.month_alarm);
1028 acpi_gbl_FADT.month_alarm = 0;
1029 }
1030
1031 acpi_rtc_info.rtc_day_alarm = acpi_gbl_FADT.day_alarm;
1032 acpi_rtc_info.rtc_mon_alarm = acpi_gbl_FADT.month_alarm;
1033 acpi_rtc_info.rtc_century = acpi_gbl_FADT.century;
1034
1035 /* NOTE: S4_RTC_WAKE is NOT currently useful to Linux */
1036 if (acpi_gbl_FADT.flags & ACPI_FADT_S4_RTC_WAKE)
1037 dev_info(dev, "RTC can wake from S4\n");
1038
1039 dev->platform_data = &acpi_rtc_info;
1040
1041 /* RTC always wakes from S1/S2/S3, and often S4/STD */
1042 device_init_wakeup(dev, 1);
1043}
1044
1045#else
1046
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -08001047static void cmos_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001048{
1049}
1050
1051#endif
1052
Marko Vrh41ac8df2007-05-08 00:34:09 -07001053#ifdef CONFIG_PNP
David Brownell7be2c7c2007-02-10 01:46:02 -08001054
1055#include <linux/pnp.h>
1056
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -08001057static int cmos_pnp_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
David Brownell7be2c7c2007-02-10 01:46:02 -08001058{
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001059 cmos_wake_setup(&pnp->dev);
1060
Sachin Kamat5e8599d2013-07-03 15:05:45 -07001061 if (pnp_port_start(pnp, 0) == 0x70 && !pnp_irq_valid(pnp, 0))
Matthew Garrett6cd8fa82007-06-01 00:46:51 -07001062 /* Some machines contain a PNP entry for the RTC, but
1063 * don't define the IRQ. It should always be safe to
1064 * hardcode it in these cases
1065 */
Bjorn Helgaas8766ad02008-04-28 16:34:27 -06001066 return cmos_do_probe(&pnp->dev,
1067 pnp_get_resource(pnp, IORESOURCE_IO, 0), 8);
Matthew Garrett6cd8fa82007-06-01 00:46:51 -07001068 else
1069 return cmos_do_probe(&pnp->dev,
Bjorn Helgaas8766ad02008-04-28 16:34:27 -06001070 pnp_get_resource(pnp, IORESOURCE_IO, 0),
1071 pnp_irq(pnp, 0));
David Brownell7be2c7c2007-02-10 01:46:02 -08001072}
1073
1074static void __exit cmos_pnp_remove(struct pnp_dev *pnp)
1075{
1076 cmos_do_remove(&pnp->dev);
1077}
1078
OGAWA Hirofumi004731b2010-01-08 14:43:11 -08001079static void cmos_pnp_shutdown(struct pnp_dev *pnp)
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001080{
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001081 struct device *dev = &pnp->dev;
1082 struct cmos_rtc *cmos = dev_get_drvdata(dev);
1083
Adrian Huang88b8d332015-07-06 12:19:12 +08001084 if (system_state == SYSTEM_POWER_OFF) {
1085 int retval = cmos_poweroff(dev);
1086
1087 if (cmos_aie_poweroff(dev) < 0 && !retval)
1088 return;
1089 }
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001090
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001091 cmos_do_shutdown(cmos->irq);
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001092}
David Brownell7be2c7c2007-02-10 01:46:02 -08001093
1094static const struct pnp_device_id rtc_ids[] = {
1095 { .id = "PNP0b00", },
1096 { .id = "PNP0b01", },
1097 { .id = "PNP0b02", },
1098 { },
1099};
1100MODULE_DEVICE_TABLE(pnp, rtc_ids);
1101
1102static struct pnp_driver cmos_pnp_driver = {
1103 .name = (char *) driver_name,
1104 .id_table = rtc_ids,
1105 .probe = cmos_pnp_probe,
1106 .remove = __exit_p(cmos_pnp_remove),
OGAWA Hirofumi004731b2010-01-08 14:43:11 -08001107 .shutdown = cmos_pnp_shutdown,
David Brownell7be2c7c2007-02-10 01:46:02 -08001108
1109 /* flag ensures resume() gets called, and stops syslog spam */
1110 .flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
Shuah Khana8a38082013-09-11 14:23:11 -07001111 .driver = {
1112 .pm = &cmos_pm_ops,
1113 },
David Brownell7be2c7c2007-02-10 01:46:02 -08001114};
1115
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001116#endif /* CONFIG_PNP */
David Brownell7be2c7c2007-02-10 01:46:02 -08001117
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001118#ifdef CONFIG_OF
1119static const struct of_device_id of_cmos_match[] = {
1120 {
1121 .compatible = "motorola,mc146818",
1122 },
1123 { },
1124};
1125MODULE_DEVICE_TABLE(of, of_cmos_match);
1126
1127static __init void cmos_of_init(struct platform_device *pdev)
1128{
1129 struct device_node *node = pdev->dev.of_node;
1130 struct rtc_time time;
1131 int ret;
1132 const __be32 *val;
1133
1134 if (!node)
1135 return;
1136
1137 val = of_get_property(node, "ctrl-reg", NULL);
1138 if (val)
1139 CMOS_WRITE(be32_to_cpup(val), RTC_CONTROL);
1140
1141 val = of_get_property(node, "freq-reg", NULL);
1142 if (val)
1143 CMOS_WRITE(be32_to_cpup(val), RTC_FREQ_SELECT);
1144
1145 get_rtc_time(&time);
1146 ret = rtc_valid_tm(&time);
1147 if (ret) {
1148 struct rtc_time def_time = {
1149 .tm_year = 1,
1150 .tm_mday = 1,
1151 };
1152 set_rtc_time(&def_time);
1153 }
1154}
1155#else
1156static inline void cmos_of_init(struct platform_device *pdev) {}
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001157#endif
David Brownell7be2c7c2007-02-10 01:46:02 -08001158/*----------------------------------------------------------------*/
1159
Marko Vrh41ac8df2007-05-08 00:34:09 -07001160/* Platform setup should have set up an RTC device, when PNP is
David Brownellbcd9b892007-04-01 23:49:47 -07001161 * unavailable ... this could happen even on (older) PCs.
David Brownell7be2c7c2007-02-10 01:46:02 -08001162 */
1163
1164static int __init cmos_platform_probe(struct platform_device *pdev)
1165{
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001166 struct resource *resource;
1167 int irq;
1168
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001169 cmos_of_init(pdev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001170 cmos_wake_setup(&pdev->dev);
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001171
1172 if (RTC_IOMAPPED)
1173 resource = platform_get_resource(pdev, IORESOURCE_IO, 0);
1174 else
1175 resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1176 irq = platform_get_irq(pdev, 0);
1177 if (irq < 0)
1178 irq = -1;
1179
1180 return cmos_do_probe(&pdev->dev, resource, irq);
David Brownell7be2c7c2007-02-10 01:46:02 -08001181}
1182
1183static int __exit cmos_platform_remove(struct platform_device *pdev)
1184{
1185 cmos_do_remove(&pdev->dev);
1186 return 0;
1187}
1188
1189static void cmos_platform_shutdown(struct platform_device *pdev)
1190{
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001191 struct device *dev = &pdev->dev;
1192 struct cmos_rtc *cmos = dev_get_drvdata(dev);
1193
Adrian Huang88b8d332015-07-06 12:19:12 +08001194 if (system_state == SYSTEM_POWER_OFF) {
1195 int retval = cmos_poweroff(dev);
1196
1197 if (cmos_aie_poweroff(dev) < 0 && !retval)
1198 return;
1199 }
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001200
Maciej W. Rozycki31632db2014-06-06 14:35:49 -07001201 cmos_do_shutdown(cmos->irq);
David Brownell7be2c7c2007-02-10 01:46:02 -08001202}
1203
Kay Sieversad28a072008-04-10 21:29:25 -07001204/* work with hotplug and coldplug */
1205MODULE_ALIAS("platform:rtc_cmos");
1206
David Brownell7be2c7c2007-02-10 01:46:02 -08001207static struct platform_driver cmos_platform_driver = {
1208 .remove = __exit_p(cmos_platform_remove),
1209 .shutdown = cmos_platform_shutdown,
1210 .driver = {
Geert Uytterhoevenc823a202014-01-23 15:55:11 -08001211 .name = driver_name,
Paul Fox2fb08e62011-01-12 17:00:07 -08001212#ifdef CONFIG_PM
1213 .pm = &cmos_pm_ops,
1214#endif
Sachin Kamatc8a60462013-02-21 16:44:28 -08001215 .of_match_table = of_match_ptr(of_cmos_match),
David Brownell7be2c7c2007-02-10 01:46:02 -08001216 }
1217};
1218
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001219#ifdef CONFIG_PNP
1220static bool pnp_driver_registered;
1221#endif
1222static bool platform_driver_registered;
1223
David Brownell7be2c7c2007-02-10 01:46:02 -08001224static int __init cmos_init(void)
1225{
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001226 int retval = 0;
1227
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001228#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001229 retval = pnp_register_driver(&cmos_pnp_driver);
1230 if (retval == 0)
1231 pnp_driver_registered = true;
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001232#endif
1233
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001234 if (!cmos_rtc.dev) {
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001235 retval = platform_driver_probe(&cmos_platform_driver,
1236 cmos_platform_probe);
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001237 if (retval == 0)
1238 platform_driver_registered = true;
1239 }
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001240
1241 if (retval == 0)
1242 return 0;
1243
1244#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001245 if (pnp_driver_registered)
1246 pnp_unregister_driver(&cmos_pnp_driver);
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001247#endif
1248 return retval;
David Brownell7be2c7c2007-02-10 01:46:02 -08001249}
1250module_init(cmos_init);
1251
1252static void __exit cmos_exit(void)
1253{
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001254#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001255 if (pnp_driver_registered)
1256 pnp_unregister_driver(&cmos_pnp_driver);
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001257#endif
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001258 if (platform_driver_registered)
1259 platform_driver_unregister(&cmos_platform_driver);
David Brownell7be2c7c2007-02-10 01:46:02 -08001260}
1261module_exit(cmos_exit);
1262
1263
David Brownell7be2c7c2007-02-10 01:46:02 -08001264MODULE_AUTHOR("David Brownell");
1265MODULE_DESCRIPTION("Driver for PC-style 'CMOS' RTCs");
1266MODULE_LICENSE("GPL");