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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 */
31#include <linux/kernel.h>
32#include <linux/module.h>
33#include <linux/init.h>
34#include <linux/interrupt.h>
35#include <linux/spinlock.h>
36#include <linux/platform_device.h>
37#include <linux/mod_devicetable.h>
Jonathan Cameron5d2a5032009-01-06 14:42:12 -080038#include <linux/log2.h>
Paul Fox2fb08e62011-01-12 17:00:07 -080039#include <linux/pm.h>
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +010040#include <linux/of.h>
41#include <linux/of_platform.h>
David Brownell7be2c7c2007-02-10 01:46:02 -080042
43/* this is for "generic access to PC-style RTC" using CMOS_READ/CMOS_WRITE */
44#include <asm-generic/rtc.h>
45
David Brownell7be2c7c2007-02-10 01:46:02 -080046struct cmos_rtc {
47 struct rtc_device *rtc;
48 struct device *dev;
49 int irq;
50 struct resource *iomem;
51
David Brownell87ac84f2007-05-08 00:34:00 -070052 void (*wake_on)(struct device *);
53 void (*wake_off)(struct device *);
54
55 u8 enabled_wake;
David Brownell7be2c7c2007-02-10 01:46:02 -080056 u8 suspend_ctrl;
57
58 /* newer hardware extends the original register set */
59 u8 day_alrm;
60 u8 mon_alrm;
61 u8 century;
62};
63
64/* both platform and pnp busses use negative numbers for invalid irqs */
Anton Vorontsov2fac6672009-01-06 14:42:11 -080065#define is_valid_irq(n) ((n) > 0)
David Brownell7be2c7c2007-02-10 01:46:02 -080066
67static const char driver_name[] = "rtc_cmos";
68
David Brownellbcd9b892007-04-01 23:49:47 -070069/* The RTC_INTR register may have e.g. RTC_PF set even if RTC_PIE is clear;
70 * always mask it against the irq enable bits in RTC_CONTROL. Bit values
71 * are the same: PF==PIE, AF=AIE, UF=UIE; so RTC_IRQMASK works with both.
72 */
73#define RTC_IRQMASK (RTC_PF | RTC_AF | RTC_UF)
74
75static inline int is_intr(u8 rtc_intr)
76{
77 if (!(rtc_intr & RTC_IRQF))
78 return 0;
79 return rtc_intr & RTC_IRQMASK;
80}
81
David Brownell7be2c7c2007-02-10 01:46:02 -080082/*----------------------------------------------------------------*/
83
David Brownell35d3fdd2008-07-23 21:30:43 -070084/* Much modern x86 hardware has HPETs (10+ MHz timers) which, because
85 * many BIOS programmers don't set up "sane mode" IRQ routing, are mostly
86 * used in a broken "legacy replacement" mode. The breakage includes
87 * HPET #1 hijacking the IRQ for this RTC, and being unavailable for
88 * other (better) use.
89 *
90 * When that broken mode is in use, platform glue provides a partial
91 * emulation of hardware RTC IRQ facilities using HPET #1. We don't
92 * want to use HPET for anything except those IRQs though...
93 */
94#ifdef CONFIG_HPET_EMULATE_RTC
95#include <asm/hpet.h>
96#else
97
98static inline int is_hpet_enabled(void)
99{
100 return 0;
101}
102
103static inline int hpet_mask_rtc_irq_bit(unsigned long mask)
104{
105 return 0;
106}
107
108static inline int hpet_set_rtc_irq_bit(unsigned long mask)
109{
110 return 0;
111}
112
113static inline int
114hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned char sec)
115{
116 return 0;
117}
118
119static inline int hpet_set_periodic_freq(unsigned long freq)
120{
121 return 0;
122}
123
124static inline int hpet_rtc_dropped_irq(void)
125{
126 return 0;
127}
128
129static inline int hpet_rtc_timer_init(void)
130{
131 return 0;
132}
133
134extern irq_handler_t hpet_rtc_interrupt;
135
136static inline int hpet_register_irq_handler(irq_handler_t handler)
137{
138 return 0;
139}
140
141static inline int hpet_unregister_irq_handler(irq_handler_t handler)
142{
143 return 0;
144}
145
146#endif
147
148/*----------------------------------------------------------------*/
149
David Brownellc8fc40c2008-10-18 20:27:47 -0700150#ifdef RTC_PORT
151
152/* Most newer x86 systems have two register banks, the first used
153 * for RTC and NVRAM and the second only for NVRAM. Caller must
154 * own rtc_lock ... and we won't worry about access during NMI.
155 */
156#define can_bank2 true
157
158static inline unsigned char cmos_read_bank2(unsigned char addr)
159{
160 outb(addr, RTC_PORT(2));
161 return inb(RTC_PORT(3));
162}
163
164static inline void cmos_write_bank2(unsigned char val, unsigned char addr)
165{
166 outb(addr, RTC_PORT(2));
Ondrej Zaryb43c1ea2012-01-10 15:10:26 -0800167 outb(val, RTC_PORT(3));
David Brownellc8fc40c2008-10-18 20:27:47 -0700168}
169
170#else
171
172#define can_bank2 false
173
174static inline unsigned char cmos_read_bank2(unsigned char addr)
175{
176 return 0;
177}
178
179static inline void cmos_write_bank2(unsigned char val, unsigned char addr)
180{
181}
182
183#endif
184
185/*----------------------------------------------------------------*/
186
David Brownell7be2c7c2007-02-10 01:46:02 -0800187static int cmos_read_time(struct device *dev, struct rtc_time *t)
188{
189 /* REVISIT: if the clock has a "century" register, use
190 * that instead of the heuristic in get_rtc_time().
191 * That'll make Y3K compatility (year > 2070) easy!
192 */
193 get_rtc_time(t);
194 return 0;
195}
196
197static int cmos_set_time(struct device *dev, struct rtc_time *t)
198{
199 /* REVISIT: set the "century" register if available
200 *
201 * NOTE: this ignores the issue whereby updating the seconds
202 * takes effect exactly 500ms after we write the register.
203 * (Also queueing and other delays before we get this far.)
204 */
205 return set_rtc_time(t);
206}
207
208static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
209{
210 struct cmos_rtc *cmos = dev_get_drvdata(dev);
211 unsigned char rtc_control;
212
213 if (!is_valid_irq(cmos->irq))
214 return -EIO;
215
216 /* Basic alarms only support hour, minute, and seconds fields.
217 * Some also support day and month, for alarms up to a year in
218 * the future.
219 */
220 t->time.tm_mday = -1;
221 t->time.tm_mon = -1;
222
223 spin_lock_irq(&rtc_lock);
224 t->time.tm_sec = CMOS_READ(RTC_SECONDS_ALARM);
225 t->time.tm_min = CMOS_READ(RTC_MINUTES_ALARM);
226 t->time.tm_hour = CMOS_READ(RTC_HOURS_ALARM);
227
228 if (cmos->day_alrm) {
Mark Lord615bb292007-11-03 22:04:03 -0400229 /* ignore upper bits on readback per ACPI spec */
230 t->time.tm_mday = CMOS_READ(cmos->day_alrm) & 0x3f;
David Brownell7be2c7c2007-02-10 01:46:02 -0800231 if (!t->time.tm_mday)
232 t->time.tm_mday = -1;
233
234 if (cmos->mon_alrm) {
235 t->time.tm_mon = CMOS_READ(cmos->mon_alrm);
236 if (!t->time.tm_mon)
237 t->time.tm_mon = -1;
238 }
239 }
240
241 rtc_control = CMOS_READ(RTC_CONTROL);
242 spin_unlock_irq(&rtc_lock);
243
Arnaud Patard3804a892010-04-29 11:58:44 +0200244 if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
245 if (((unsigned)t->time.tm_sec) < 0x60)
246 t->time.tm_sec = bcd2bin(t->time.tm_sec);
David Brownell7be2c7c2007-02-10 01:46:02 -0800247 else
Arnaud Patard3804a892010-04-29 11:58:44 +0200248 t->time.tm_sec = -1;
249 if (((unsigned)t->time.tm_min) < 0x60)
250 t->time.tm_min = bcd2bin(t->time.tm_min);
251 else
252 t->time.tm_min = -1;
253 if (((unsigned)t->time.tm_hour) < 0x24)
254 t->time.tm_hour = bcd2bin(t->time.tm_hour);
255 else
256 t->time.tm_hour = -1;
257
258 if (cmos->day_alrm) {
259 if (((unsigned)t->time.tm_mday) <= 0x31)
260 t->time.tm_mday = bcd2bin(t->time.tm_mday);
David Brownell7be2c7c2007-02-10 01:46:02 -0800261 else
Arnaud Patard3804a892010-04-29 11:58:44 +0200262 t->time.tm_mday = -1;
263
264 if (cmos->mon_alrm) {
265 if (((unsigned)t->time.tm_mon) <= 0x12)
266 t->time.tm_mon = bcd2bin(t->time.tm_mon)-1;
267 else
268 t->time.tm_mon = -1;
269 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800270 }
271 }
272 t->time.tm_year = -1;
273
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);
Arnaud Patard3804a892010-04-29 11:58:44 +0200329 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
377 return 0;
378}
379
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800380static int cmos_alarm_irq_enable(struct device *dev, unsigned int enabled)
David Brownell7be2c7c2007-02-10 01:46:02 -0800381{
382 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownell7be2c7c2007-02-10 01:46:02 -0800383 unsigned long flags;
384
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800385 if (!is_valid_irq(cmos->irq))
386 return -EINVAL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800387
388 spin_lock_irqsave(&rtc_lock, flags);
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800389
390 if (enabled)
David Brownell7e2a31d2008-07-23 21:30:47 -0700391 cmos_irq_enable(cmos, RTC_AIE);
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800392 else
393 cmos_irq_disable(cmos, RTC_AIE);
394
David Brownell7be2c7c2007-02-10 01:46:02 -0800395 spin_unlock_irqrestore(&rtc_lock, flags);
396 return 0;
397}
398
David Brownell7be2c7c2007-02-10 01:46:02 -0800399#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
400
401static int cmos_procfs(struct device *dev, struct seq_file *seq)
402{
403 struct cmos_rtc *cmos = dev_get_drvdata(dev);
404 unsigned char rtc_control, valid;
405
406 spin_lock_irq(&rtc_lock);
407 rtc_control = CMOS_READ(RTC_CONTROL);
408 valid = CMOS_READ(RTC_VALID);
409 spin_unlock_irq(&rtc_lock);
410
411 /* NOTE: at least ICH6 reports battery status using a different
412 * (non-RTC) bit; and SQWE is ignored on many current systems.
413 */
414 return seq_printf(seq,
415 "periodic_IRQ\t: %s\n"
416 "update_IRQ\t: %s\n"
David Brownellc8626a12008-02-23 15:23:44 -0800417 "HPET_emulated\t: %s\n"
David Brownell7be2c7c2007-02-10 01:46:02 -0800418 // "square_wave\t: %s\n"
Arnaud Patard3804a892010-04-29 11:58:44 +0200419 "BCD\t\t: %s\n"
David Brownell7be2c7c2007-02-10 01:46:02 -0800420 "DST_enable\t: %s\n"
421 "periodic_freq\t: %d\n"
422 "batt_status\t: %s\n",
423 (rtc_control & RTC_PIE) ? "yes" : "no",
424 (rtc_control & RTC_UIE) ? "yes" : "no",
David Brownellc8626a12008-02-23 15:23:44 -0800425 is_hpet_enabled() ? "yes" : "no",
David Brownell7be2c7c2007-02-10 01:46:02 -0800426 // (rtc_control & RTC_SQWE) ? "yes" : "no",
Arnaud Patard3804a892010-04-29 11:58:44 +0200427 (rtc_control & RTC_DM_BINARY) ? "no" : "yes",
David Brownell7be2c7c2007-02-10 01:46:02 -0800428 (rtc_control & RTC_DST_EN) ? "yes" : "no",
429 cmos->rtc->irq_freq,
430 (valid & RTC_VRT) ? "okay" : "dead");
431}
432
433#else
434#define cmos_procfs NULL
435#endif
436
437static const struct rtc_class_ops cmos_rtc_ops = {
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800438 .read_time = cmos_read_time,
439 .set_time = cmos_set_time,
440 .read_alarm = cmos_read_alarm,
441 .set_alarm = cmos_set_alarm,
442 .proc = cmos_procfs,
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800443 .alarm_irq_enable = cmos_alarm_irq_enable,
David Brownell7be2c7c2007-02-10 01:46:02 -0800444};
445
446/*----------------------------------------------------------------*/
447
David Brownelle07e2322008-02-06 01:38:43 -0800448/*
449 * All these chips have at least 64 bytes of address space, shared by
450 * RTC registers and NVRAM. Most of those bytes of NVRAM are used
451 * by boot firmware. Modern chips have 128 or 256 bytes.
452 */
453
454#define NVRAM_OFFSET (RTC_REG_D + 1)
455
456static ssize_t
Chris Wright2c3c8be2010-05-12 18:28:57 -0700457cmos_nvram_read(struct file *filp, struct kobject *kobj,
458 struct bin_attribute *attr,
David Brownelle07e2322008-02-06 01:38:43 -0800459 char *buf, loff_t off, size_t count)
460{
461 int retval;
462
463 if (unlikely(off >= attr->size))
464 return 0;
David Brownellc8fc40c2008-10-18 20:27:47 -0700465 if (unlikely(off < 0))
466 return -EINVAL;
David Brownelle07e2322008-02-06 01:38:43 -0800467 if ((off + count) > attr->size)
468 count = attr->size - off;
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));
494 if (unlikely(off >= attr->size))
495 return -EFBIG;
David Brownellc8fc40c2008-10-18 20:27:47 -0700496 if (unlikely(off < 0))
497 return -EINVAL;
David Brownelle07e2322008-02-06 01:38:43 -0800498 if ((off + count) > attr->size)
499 count = attr->size - off;
500
501 /* NOTE: on at least PCs and Ataris, the boot firmware uses a
502 * checksum on part of the NVRAM data. That's currently ignored
503 * here. If userspace is smart enough to know what fields of
504 * NVRAM to update, updating checksums is also part of its job.
505 */
David Brownellc8fc40c2008-10-18 20:27:47 -0700506 off += NVRAM_OFFSET;
David Brownelle07e2322008-02-06 01:38:43 -0800507 spin_lock_irq(&rtc_lock);
David Brownellc8fc40c2008-10-18 20:27:47 -0700508 for (retval = 0; count; count--, off++, retval++) {
David Brownelle07e2322008-02-06 01:38:43 -0800509 /* don't trash RTC registers */
510 if (off == cmos->day_alrm
511 || off == cmos->mon_alrm
512 || off == cmos->century)
513 buf++;
David Brownellc8fc40c2008-10-18 20:27:47 -0700514 else if (off < 128)
David Brownelle07e2322008-02-06 01:38:43 -0800515 CMOS_WRITE(*buf++, off);
David Brownellc8fc40c2008-10-18 20:27:47 -0700516 else if (can_bank2)
517 cmos_write_bank2(*buf++, off);
518 else
519 break;
David Brownelle07e2322008-02-06 01:38:43 -0800520 }
521 spin_unlock_irq(&rtc_lock);
522
523 return retval;
524}
525
526static struct bin_attribute nvram = {
527 .attr = {
528 .name = "nvram",
529 .mode = S_IRUGO | S_IWUSR,
David Brownelle07e2322008-02-06 01:38:43 -0800530 },
531
532 .read = cmos_nvram_read,
533 .write = cmos_nvram_write,
534 /* size gets set up later */
535};
536
537/*----------------------------------------------------------------*/
538
David Brownell7be2c7c2007-02-10 01:46:02 -0800539static struct cmos_rtc cmos_rtc;
540
541static irqreturn_t cmos_interrupt(int irq, void *p)
542{
543 u8 irqstat;
David Brownell8a0bdfd2008-02-06 01:38:45 -0800544 u8 rtc_control;
David Brownell7be2c7c2007-02-10 01:46:02 -0800545
546 spin_lock(&rtc_lock);
David Brownell35d3fdd2008-07-23 21:30:43 -0700547
548 /* When the HPET interrupt handler calls us, the interrupt
549 * status is passed as arg1 instead of the irq number. But
550 * always clear irq status, even when HPET is in the way.
551 *
552 * Note that HPET and RTC are almost certainly out of phase,
553 * giving different IRQ status ...
Bernhard Walle9d8af782008-02-06 01:38:52 -0800554 */
David Brownell35d3fdd2008-07-23 21:30:43 -0700555 irqstat = CMOS_READ(RTC_INTR_FLAGS);
556 rtc_control = CMOS_READ(RTC_CONTROL);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800557 if (is_hpet_enabled())
558 irqstat = (unsigned long)irq & 0xF0;
David Brownell35d3fdd2008-07-23 21:30:43 -0700559 irqstat &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
David Brownell8a0bdfd2008-02-06 01:38:45 -0800560
561 /* All Linux RTC alarms should be treated as if they were oneshot.
562 * Similar code may be needed in system wakeup paths, in case the
563 * alarm woke the system.
564 */
565 if (irqstat & RTC_AIE) {
566 rtc_control &= ~RTC_AIE;
567 CMOS_WRITE(rtc_control, RTC_CONTROL);
David Brownell35d3fdd2008-07-23 21:30:43 -0700568 hpet_mask_rtc_irq_bit(RTC_AIE);
569
David Brownell8a0bdfd2008-02-06 01:38:45 -0800570 CMOS_READ(RTC_INTR_FLAGS);
571 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800572 spin_unlock(&rtc_lock);
573
David Brownellbcd9b892007-04-01 23:49:47 -0700574 if (is_intr(irqstat)) {
David Brownell7be2c7c2007-02-10 01:46:02 -0800575 rtc_update_irq(p, 1, irqstat);
576 return IRQ_HANDLED;
577 } else
578 return IRQ_NONE;
579}
580
Marko Vrh41ac8df2007-05-08 00:34:09 -0700581#ifdef CONFIG_PNP
David Brownell7be2c7c2007-02-10 01:46:02 -0800582#define INITSECTION
583
584#else
David Brownell7be2c7c2007-02-10 01:46:02 -0800585#define INITSECTION __init
586#endif
587
588static int INITSECTION
589cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
590{
591 struct cmos_rtc_board_info *info = dev->platform_data;
592 int retval = 0;
593 unsigned char rtc_control;
David Brownelle07e2322008-02-06 01:38:43 -0800594 unsigned address_space;
David Brownell7be2c7c2007-02-10 01:46:02 -0800595
596 /* there can be only one ... */
597 if (cmos_rtc.dev)
598 return -EBUSY;
599
600 if (!ports)
601 return -ENODEV;
602
David Brownell05440df2007-10-16 01:28:21 -0700603 /* Claim I/O ports ASAP, minimizing conflict with legacy driver.
604 *
605 * REVISIT non-x86 systems may instead use memory space resources
606 * (needing ioremap etc), not i/o space resources like this ...
607 */
608 ports = request_region(ports->start,
Joe Perches28f65c112011-06-09 09:13:32 -0700609 resource_size(ports),
David Brownell05440df2007-10-16 01:28:21 -0700610 driver_name);
611 if (!ports) {
612 dev_dbg(dev, "i/o registers already in use\n");
613 return -EBUSY;
614 }
615
David Brownell7be2c7c2007-02-10 01:46:02 -0800616 cmos_rtc.irq = rtc_irq;
617 cmos_rtc.iomem = ports;
618
David Brownelle07e2322008-02-06 01:38:43 -0800619 /* Heuristic to deduce NVRAM size ... do what the legacy NVRAM
620 * driver did, but don't reject unknown configs. Old hardware
David Brownellc8fc40c2008-10-18 20:27:47 -0700621 * won't address 128 bytes. Newer chips have multiple banks,
622 * though they may not be listed in one I/O resource.
David Brownelle07e2322008-02-06 01:38:43 -0800623 */
624#if defined(CONFIG_ATARI)
625 address_space = 64;
Wu Zhangjin95abd0d2009-11-05 09:21:54 +0800626#elif defined(__i386__) || defined(__x86_64__) || defined(__arm__) \
Srikanth Krishnakar8cb7c712010-10-14 04:03:35 +0000627 || defined(__sparc__) || defined(__mips__) \
628 || defined(__powerpc__)
David Brownelle07e2322008-02-06 01:38:43 -0800629 address_space = 128;
630#else
631#warning Assuming 128 bytes of RTC+NVRAM address space, not 64 bytes.
632 address_space = 128;
633#endif
David Brownellc8fc40c2008-10-18 20:27:47 -0700634 if (can_bank2 && ports->end > (ports->start + 1))
635 address_space = 256;
David Brownelle07e2322008-02-06 01:38:43 -0800636
David Brownell87ac84f2007-05-08 00:34:00 -0700637 /* For ACPI systems extension info comes from the FADT. On others,
638 * board specific setup provides it as appropriate. Systems where
639 * the alarm IRQ isn't automatically a wakeup IRQ (like ACPI, and
640 * some almost-clones) can provide hooks to make that behave.
David Brownelle07e2322008-02-06 01:38:43 -0800641 *
642 * Note that ACPI doesn't preclude putting these registers into
643 * "extended" areas of the chip, including some that we won't yet
644 * expect CMOS_READ and friends to handle.
David Brownell7be2c7c2007-02-10 01:46:02 -0800645 */
646 if (info) {
David Brownelle07e2322008-02-06 01:38:43 -0800647 if (info->rtc_day_alarm && info->rtc_day_alarm < 128)
648 cmos_rtc.day_alrm = info->rtc_day_alarm;
649 if (info->rtc_mon_alarm && info->rtc_mon_alarm < 128)
650 cmos_rtc.mon_alrm = info->rtc_mon_alarm;
651 if (info->rtc_century && info->rtc_century < 128)
652 cmos_rtc.century = info->rtc_century;
David Brownell87ac84f2007-05-08 00:34:00 -0700653
654 if (info->wake_on && info->wake_off) {
655 cmos_rtc.wake_on = info->wake_on;
656 cmos_rtc.wake_off = info->wake_off;
657 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800658 }
659
Dan Carpenter6ba8bcd2010-05-24 14:33:49 -0700660 cmos_rtc.dev = dev;
661 dev_set_drvdata(dev, &cmos_rtc);
662
David Brownell7be2c7c2007-02-10 01:46:02 -0800663 cmos_rtc.rtc = rtc_device_register(driver_name, dev,
664 &cmos_rtc_ops, THIS_MODULE);
David Brownell05440df2007-10-16 01:28:21 -0700665 if (IS_ERR(cmos_rtc.rtc)) {
666 retval = PTR_ERR(cmos_rtc.rtc);
667 goto cleanup0;
668 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800669
Kay Sieversd4afc762009-01-06 14:42:11 -0800670 rename_region(ports, dev_name(&cmos_rtc.rtc->dev));
David Brownell7be2c7c2007-02-10 01:46:02 -0800671
672 spin_lock_irq(&rtc_lock);
673
674 /* force periodic irq to CMOS reset default of 1024Hz;
675 *
676 * REVISIT it's been reported that at least one x86_64 ALI mobo
677 * doesn't use 32KHz here ... for portability we might need to
678 * do something about other clock frequencies.
679 */
David Brownell7be2c7c2007-02-10 01:46:02 -0800680 cmos_rtc.rtc->irq_freq = 1024;
David Brownell35d3fdd2008-07-23 21:30:43 -0700681 hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq);
682 CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
David Brownell7be2c7c2007-02-10 01:46:02 -0800683
David Brownell7e2a31d2008-07-23 21:30:47 -0700684 /* disable irqs */
685 cmos_irq_disable(&cmos_rtc, RTC_PIE | RTC_AIE | RTC_UIE);
David Brownell35d3fdd2008-07-23 21:30:43 -0700686
David Brownell7e2a31d2008-07-23 21:30:47 -0700687 rtc_control = CMOS_READ(RTC_CONTROL);
David Brownell7be2c7c2007-02-10 01:46:02 -0800688
689 spin_unlock_irq(&rtc_lock);
690
Arnaud Patard3804a892010-04-29 11:58:44 +0200691 /* FIXME:
David Brownell7be2c7c2007-02-10 01:46:02 -0800692 * <asm-generic/rtc.h> doesn't know 12-hour mode either.
693 */
Arnaud Patard3804a892010-04-29 11:58:44 +0200694 if (is_valid_irq(rtc_irq) && !(rtc_control & RTC_24H)) {
695 dev_warn(dev, "only 24-hr supported\n");
David Brownell7be2c7c2007-02-10 01:46:02 -0800696 retval = -ENXIO;
697 goto cleanup1;
698 }
699
Bernhard Walle9d8af782008-02-06 01:38:52 -0800700 if (is_valid_irq(rtc_irq)) {
701 irq_handler_t rtc_cmos_int_handler;
702
703 if (is_hpet_enabled()) {
704 int err;
705
706 rtc_cmos_int_handler = hpet_rtc_interrupt;
707 err = hpet_register_irq_handler(cmos_interrupt);
708 if (err != 0) {
Jingoo Hanee443352013-02-21 16:45:34 -0800709 dev_warn(dev, "hpet_register_irq_handler "
Bernhard Walle9d8af782008-02-06 01:38:52 -0800710 " failed in rtc_init().");
711 goto cleanup1;
712 }
713 } else
714 rtc_cmos_int_handler = cmos_interrupt;
715
716 retval = request_irq(rtc_irq, rtc_cmos_int_handler,
Yong Zhang2f6e5f92012-03-23 15:02:34 -0700717 0, dev_name(&cmos_rtc.rtc->dev),
David Brownellab6a2d72007-05-08 00:33:30 -0700718 cmos_rtc.rtc);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800719 if (retval < 0) {
720 dev_dbg(dev, "IRQ %d is already in use\n", rtc_irq);
721 goto cleanup1;
722 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800723 }
Bernhard Walle9d8af782008-02-06 01:38:52 -0800724 hpet_rtc_timer_init();
David Brownell7be2c7c2007-02-10 01:46:02 -0800725
David Brownelle07e2322008-02-06 01:38:43 -0800726 /* export at least the first block of NVRAM */
727 nvram.size = address_space - NVRAM_OFFSET;
728 retval = sysfs_create_bin_file(&dev->kobj, &nvram);
729 if (retval < 0) {
730 dev_dbg(dev, "can't create nvram file? %d\n", retval);
731 goto cleanup2;
732 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800733
Jingoo Hanee443352013-02-21 16:45:34 -0800734 dev_info(dev, "%s%s, %zd bytes nvram%s\n",
Krzysztof Halasa6d029b62009-04-21 12:24:49 -0700735 !is_valid_irq(rtc_irq) ? "no alarms" :
736 cmos_rtc.mon_alrm ? "alarms up to one year" :
737 cmos_rtc.day_alrm ? "alarms up to one month" :
738 "alarms up to one day",
739 cmos_rtc.century ? ", y3k" : "",
740 nvram.size,
741 is_hpet_enabled() ? ", hpet irqs" : "");
David Brownell7be2c7c2007-02-10 01:46:02 -0800742
743 return 0;
744
David Brownelle07e2322008-02-06 01:38:43 -0800745cleanup2:
746 if (is_valid_irq(rtc_irq))
747 free_irq(rtc_irq, cmos_rtc.rtc);
David Brownell7be2c7c2007-02-10 01:46:02 -0800748cleanup1:
David Brownell05440df2007-10-16 01:28:21 -0700749 cmos_rtc.dev = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800750 rtc_device_unregister(cmos_rtc.rtc);
David Brownell05440df2007-10-16 01:28:21 -0700751cleanup0:
Joe Perches28f65c112011-06-09 09:13:32 -0700752 release_region(ports->start, resource_size(ports));
David Brownell7be2c7c2007-02-10 01:46:02 -0800753 return retval;
754}
755
756static void cmos_do_shutdown(void)
757{
David Brownell7be2c7c2007-02-10 01:46:02 -0800758 spin_lock_irq(&rtc_lock);
David Brownell7e2a31d2008-07-23 21:30:47 -0700759 cmos_irq_disable(&cmos_rtc, RTC_IRQMASK);
David Brownell7be2c7c2007-02-10 01:46:02 -0800760 spin_unlock_irq(&rtc_lock);
761}
762
763static void __exit cmos_do_remove(struct device *dev)
764{
765 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownell05440df2007-10-16 01:28:21 -0700766 struct resource *ports;
David Brownell7be2c7c2007-02-10 01:46:02 -0800767
768 cmos_do_shutdown();
769
David Brownelle07e2322008-02-06 01:38:43 -0800770 sysfs_remove_bin_file(&dev->kobj, &nvram);
771
Bernhard Walle9d8af782008-02-06 01:38:52 -0800772 if (is_valid_irq(cmos->irq)) {
David Brownell05440df2007-10-16 01:28:21 -0700773 free_irq(cmos->irq, cmos->rtc);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800774 hpet_unregister_irq_handler(cmos_interrupt);
775 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800776
David Brownell05440df2007-10-16 01:28:21 -0700777 rtc_device_unregister(cmos->rtc);
778 cmos->rtc = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800779
David Brownell05440df2007-10-16 01:28:21 -0700780 ports = cmos->iomem;
Joe Perches28f65c112011-06-09 09:13:32 -0700781 release_region(ports->start, resource_size(ports));
David Brownell05440df2007-10-16 01:28:21 -0700782 cmos->iomem = NULL;
783
784 cmos->dev = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800785 dev_set_drvdata(dev, NULL);
786}
787
788#ifdef CONFIG_PM
789
Paul Fox2fb08e62011-01-12 17:00:07 -0800790static int cmos_suspend(struct device *dev)
David Brownell7be2c7c2007-02-10 01:46:02 -0800791{
792 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownellbcd9b892007-04-01 23:49:47 -0700793 unsigned char tmp;
David Brownell7be2c7c2007-02-10 01:46:02 -0800794
795 /* only the alarm might be a wakeup event source */
796 spin_lock_irq(&rtc_lock);
797 cmos->suspend_ctrl = tmp = CMOS_READ(RTC_CONTROL);
798 if (tmp & (RTC_PIE|RTC_AIE|RTC_UIE)) {
David Brownell35d3fdd2008-07-23 21:30:43 -0700799 unsigned char mask;
David Brownellbcd9b892007-04-01 23:49:47 -0700800
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700801 if (device_may_wakeup(dev))
David Brownell35d3fdd2008-07-23 21:30:43 -0700802 mask = RTC_IRQMASK & ~RTC_AIE;
David Brownell7be2c7c2007-02-10 01:46:02 -0800803 else
David Brownell35d3fdd2008-07-23 21:30:43 -0700804 mask = RTC_IRQMASK;
805 tmp &= ~mask;
David Brownell7be2c7c2007-02-10 01:46:02 -0800806 CMOS_WRITE(tmp, RTC_CONTROL);
Derek Basehoree0057152013-04-29 16:20:23 -0700807 hpet_mask_rtc_irq_bit(mask);
David Brownell35d3fdd2008-07-23 21:30:43 -0700808
David Brownell7e2a31d2008-07-23 21:30:47 -0700809 cmos_checkintr(cmos, tmp);
David Brownellbcd9b892007-04-01 23:49:47 -0700810 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800811 spin_unlock_irq(&rtc_lock);
812
David Brownell87ac84f2007-05-08 00:34:00 -0700813 if (tmp & RTC_AIE) {
814 cmos->enabled_wake = 1;
815 if (cmos->wake_on)
816 cmos->wake_on(dev);
817 else
818 enable_irq_wake(cmos->irq);
819 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800820
Jingoo Hanee443352013-02-21 16:45:34 -0800821 dev_dbg(dev, "suspend%s, ctrl %02x\n",
David Brownell7be2c7c2007-02-10 01:46:02 -0800822 (tmp & RTC_AIE) ? ", alarm may wake" : "",
823 tmp);
824
825 return 0;
826}
827
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700828/* We want RTC alarms to wake us from e.g. ACPI G2/S5 "soft off", even
829 * after a detour through G3 "mechanical off", although the ACPI spec
830 * says wakeup should only work from G1/S4 "hibernate". To most users,
831 * distinctions between S4 and S5 are pointless. So when the hardware
832 * allows, don't draw that distinction.
833 */
834static inline int cmos_poweroff(struct device *dev)
835{
Paul Fox2fb08e62011-01-12 17:00:07 -0800836 return cmos_suspend(dev);
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700837}
838
David Brownell7be2c7c2007-02-10 01:46:02 -0800839static int cmos_resume(struct device *dev)
840{
841 struct cmos_rtc *cmos = dev_get_drvdata(dev);
842 unsigned char tmp = cmos->suspend_ctrl;
843
David Brownell7be2c7c2007-02-10 01:46:02 -0800844 /* re-enable any irqs previously active */
David Brownell35d3fdd2008-07-23 21:30:43 -0700845 if (tmp & RTC_IRQMASK) {
846 unsigned char mask;
David Brownell7be2c7c2007-02-10 01:46:02 -0800847
David Brownell87ac84f2007-05-08 00:34:00 -0700848 if (cmos->enabled_wake) {
849 if (cmos->wake_off)
850 cmos->wake_off(dev);
851 else
852 disable_irq_wake(cmos->irq);
853 cmos->enabled_wake = 0;
854 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800855
856 spin_lock_irq(&rtc_lock);
David Brownell35d3fdd2008-07-23 21:30:43 -0700857 do {
858 CMOS_WRITE(tmp, RTC_CONTROL);
859 hpet_set_rtc_irq_bit(tmp & RTC_IRQMASK);
860
861 mask = CMOS_READ(RTC_INTR_FLAGS);
862 mask &= (tmp & RTC_IRQMASK) | RTC_IRQF;
David Brownell7e2a31d2008-07-23 21:30:47 -0700863 if (!is_hpet_enabled() || !is_intr(mask))
David Brownell35d3fdd2008-07-23 21:30:43 -0700864 break;
865
866 /* force one-shot behavior if HPET blocked
867 * the wake alarm's irq
868 */
869 rtc_update_irq(cmos->rtc, 1, mask);
870 tmp &= ~RTC_AIE;
871 hpet_mask_rtc_irq_bit(RTC_AIE);
Derek Basehoree0057152013-04-29 16:20:23 -0700872 hpet_rtc_timer_init();
David Brownell35d3fdd2008-07-23 21:30:43 -0700873 } while (mask & RTC_AIE);
David Brownellbcd9b892007-04-01 23:49:47 -0700874 spin_unlock_irq(&rtc_lock);
David Brownell7be2c7c2007-02-10 01:46:02 -0800875 }
876
Jingoo Hanee443352013-02-21 16:45:34 -0800877 dev_dbg(dev, "resume, ctrl %02x\n", tmp);
David Brownell7be2c7c2007-02-10 01:46:02 -0800878
879 return 0;
880}
881
Paul Fox2fb08e62011-01-12 17:00:07 -0800882static SIMPLE_DEV_PM_OPS(cmos_pm_ops, cmos_suspend, cmos_resume);
883
David Brownell7be2c7c2007-02-10 01:46:02 -0800884#else
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700885
886static inline int cmos_poweroff(struct device *dev)
887{
888 return -ENOSYS;
889}
890
David Brownell7be2c7c2007-02-10 01:46:02 -0800891#endif
892
893/*----------------------------------------------------------------*/
894
David Brownelle07e2322008-02-06 01:38:43 -0800895/* On non-x86 systems, a "CMOS" RTC lives most naturally on platform_bus.
896 * ACPI systems always list these as PNPACPI devices, and pre-ACPI PCs
897 * probably list them in similar PNPBIOS tables; so PNP is more common.
898 *
899 * We don't use legacy "poke at the hardware" probing. Ancient PCs that
900 * predate even PNPBIOS should set up platform_bus devices.
David Brownell7be2c7c2007-02-10 01:46:02 -0800901 */
902
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600903#ifdef CONFIG_ACPI
904
905#include <linux/acpi.h>
906
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600907static u32 rtc_handler(void *context)
908{
Daniel Drakeb2201e52012-05-18 22:59:41 +0200909 struct device *dev = context;
910
911 pm_wakeup_event(dev, 0);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600912 acpi_clear_event(ACPI_EVENT_RTC);
913 acpi_disable_event(ACPI_EVENT_RTC, 0);
914 return ACPI_INTERRUPT_HANDLED;
915}
916
Daniel Drakeb2201e52012-05-18 22:59:41 +0200917static inline void rtc_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600918{
Daniel Drakeb2201e52012-05-18 22:59:41 +0200919 acpi_install_fixed_event_handler(ACPI_EVENT_RTC, rtc_handler, dev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600920 /*
921 * After the RTC handler is installed, the Fixed_RTC event should
922 * be disabled. Only when the RTC alarm is set will it be enabled.
923 */
924 acpi_clear_event(ACPI_EVENT_RTC);
925 acpi_disable_event(ACPI_EVENT_RTC, 0);
926}
927
928static void rtc_wake_on(struct device *dev)
929{
930 acpi_clear_event(ACPI_EVENT_RTC);
931 acpi_enable_event(ACPI_EVENT_RTC, 0);
932}
933
934static void rtc_wake_off(struct device *dev)
935{
936 acpi_disable_event(ACPI_EVENT_RTC, 0);
937}
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600938
939/* Every ACPI platform has a mc146818 compatible "cmos rtc". Here we find
940 * its device node and pass extra config data. This helps its driver use
941 * capabilities that the now-obsolete mc146818 didn't have, and informs it
942 * that this board's RTC is wakeup-capable (per ACPI spec).
943 */
944static struct cmos_rtc_board_info acpi_rtc_info;
945
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -0800946static void cmos_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600947{
948 if (acpi_disabled)
949 return;
950
Daniel Drakeb2201e52012-05-18 22:59:41 +0200951 rtc_wake_setup(dev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600952 acpi_rtc_info.wake_on = rtc_wake_on;
953 acpi_rtc_info.wake_off = rtc_wake_off;
954
955 /* workaround bug in some ACPI tables */
956 if (acpi_gbl_FADT.month_alarm && !acpi_gbl_FADT.day_alarm) {
957 dev_dbg(dev, "bogus FADT month_alarm (%d)\n",
958 acpi_gbl_FADT.month_alarm);
959 acpi_gbl_FADT.month_alarm = 0;
960 }
961
962 acpi_rtc_info.rtc_day_alarm = acpi_gbl_FADT.day_alarm;
963 acpi_rtc_info.rtc_mon_alarm = acpi_gbl_FADT.month_alarm;
964 acpi_rtc_info.rtc_century = acpi_gbl_FADT.century;
965
966 /* NOTE: S4_RTC_WAKE is NOT currently useful to Linux */
967 if (acpi_gbl_FADT.flags & ACPI_FADT_S4_RTC_WAKE)
968 dev_info(dev, "RTC can wake from S4\n");
969
970 dev->platform_data = &acpi_rtc_info;
971
972 /* RTC always wakes from S1/S2/S3, and often S4/STD */
973 device_init_wakeup(dev, 1);
974}
975
976#else
977
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -0800978static void cmos_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600979{
980}
981
982#endif
983
Marko Vrh41ac8df2007-05-08 00:34:09 -0700984#ifdef CONFIG_PNP
David Brownell7be2c7c2007-02-10 01:46:02 -0800985
986#include <linux/pnp.h>
987
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -0800988static int cmos_pnp_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
David Brownell7be2c7c2007-02-10 01:46:02 -0800989{
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600990 cmos_wake_setup(&pnp->dev);
991
Matthew Garrett6cd8fa82007-06-01 00:46:51 -0700992 if (pnp_port_start(pnp,0) == 0x70 && !pnp_irq_valid(pnp,0))
993 /* Some machines contain a PNP entry for the RTC, but
994 * don't define the IRQ. It should always be safe to
995 * hardcode it in these cases
996 */
Bjorn Helgaas8766ad02008-04-28 16:34:27 -0600997 return cmos_do_probe(&pnp->dev,
998 pnp_get_resource(pnp, IORESOURCE_IO, 0), 8);
Matthew Garrett6cd8fa82007-06-01 00:46:51 -0700999 else
1000 return cmos_do_probe(&pnp->dev,
Bjorn Helgaas8766ad02008-04-28 16:34:27 -06001001 pnp_get_resource(pnp, IORESOURCE_IO, 0),
1002 pnp_irq(pnp, 0));
David Brownell7be2c7c2007-02-10 01:46:02 -08001003}
1004
1005static void __exit cmos_pnp_remove(struct pnp_dev *pnp)
1006{
1007 cmos_do_remove(&pnp->dev);
1008}
1009
1010#ifdef CONFIG_PM
1011
1012static int cmos_pnp_suspend(struct pnp_dev *pnp, pm_message_t mesg)
1013{
Paul Fox2fb08e62011-01-12 17:00:07 -08001014 return cmos_suspend(&pnp->dev);
David Brownell7be2c7c2007-02-10 01:46:02 -08001015}
1016
1017static int cmos_pnp_resume(struct pnp_dev *pnp)
1018{
1019 return cmos_resume(&pnp->dev);
1020}
1021
1022#else
1023#define cmos_pnp_suspend NULL
1024#define cmos_pnp_resume NULL
1025#endif
1026
OGAWA Hirofumi004731b2010-01-08 14:43:11 -08001027static void cmos_pnp_shutdown(struct pnp_dev *pnp)
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001028{
OGAWA Hirofumi004731b2010-01-08 14:43:11 -08001029 if (system_state == SYSTEM_POWER_OFF && !cmos_poweroff(&pnp->dev))
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001030 return;
1031
1032 cmos_do_shutdown();
1033}
David Brownell7be2c7c2007-02-10 01:46:02 -08001034
1035static const struct pnp_device_id rtc_ids[] = {
1036 { .id = "PNP0b00", },
1037 { .id = "PNP0b01", },
1038 { .id = "PNP0b02", },
1039 { },
1040};
1041MODULE_DEVICE_TABLE(pnp, rtc_ids);
1042
1043static struct pnp_driver cmos_pnp_driver = {
1044 .name = (char *) driver_name,
1045 .id_table = rtc_ids,
1046 .probe = cmos_pnp_probe,
1047 .remove = __exit_p(cmos_pnp_remove),
OGAWA Hirofumi004731b2010-01-08 14:43:11 -08001048 .shutdown = cmos_pnp_shutdown,
David Brownell7be2c7c2007-02-10 01:46:02 -08001049
1050 /* flag ensures resume() gets called, and stops syslog spam */
1051 .flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
1052 .suspend = cmos_pnp_suspend,
1053 .resume = cmos_pnp_resume,
1054};
1055
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001056#endif /* CONFIG_PNP */
David Brownell7be2c7c2007-02-10 01:46:02 -08001057
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001058#ifdef CONFIG_OF
1059static const struct of_device_id of_cmos_match[] = {
1060 {
1061 .compatible = "motorola,mc146818",
1062 },
1063 { },
1064};
1065MODULE_DEVICE_TABLE(of, of_cmos_match);
1066
1067static __init void cmos_of_init(struct platform_device *pdev)
1068{
1069 struct device_node *node = pdev->dev.of_node;
1070 struct rtc_time time;
1071 int ret;
1072 const __be32 *val;
1073
1074 if (!node)
1075 return;
1076
1077 val = of_get_property(node, "ctrl-reg", NULL);
1078 if (val)
1079 CMOS_WRITE(be32_to_cpup(val), RTC_CONTROL);
1080
1081 val = of_get_property(node, "freq-reg", NULL);
1082 if (val)
1083 CMOS_WRITE(be32_to_cpup(val), RTC_FREQ_SELECT);
1084
1085 get_rtc_time(&time);
1086 ret = rtc_valid_tm(&time);
1087 if (ret) {
1088 struct rtc_time def_time = {
1089 .tm_year = 1,
1090 .tm_mday = 1,
1091 };
1092 set_rtc_time(&def_time);
1093 }
1094}
1095#else
1096static inline void cmos_of_init(struct platform_device *pdev) {}
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001097#endif
David Brownell7be2c7c2007-02-10 01:46:02 -08001098/*----------------------------------------------------------------*/
1099
Marko Vrh41ac8df2007-05-08 00:34:09 -07001100/* Platform setup should have set up an RTC device, when PNP is
David Brownellbcd9b892007-04-01 23:49:47 -07001101 * unavailable ... this could happen even on (older) PCs.
David Brownell7be2c7c2007-02-10 01:46:02 -08001102 */
1103
1104static int __init cmos_platform_probe(struct platform_device *pdev)
1105{
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001106 cmos_of_init(pdev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001107 cmos_wake_setup(&pdev->dev);
David Brownell7be2c7c2007-02-10 01:46:02 -08001108 return cmos_do_probe(&pdev->dev,
1109 platform_get_resource(pdev, IORESOURCE_IO, 0),
1110 platform_get_irq(pdev, 0));
1111}
1112
1113static int __exit cmos_platform_remove(struct platform_device *pdev)
1114{
1115 cmos_do_remove(&pdev->dev);
1116 return 0;
1117}
1118
1119static void cmos_platform_shutdown(struct platform_device *pdev)
1120{
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001121 if (system_state == SYSTEM_POWER_OFF && !cmos_poweroff(&pdev->dev))
1122 return;
1123
David Brownell7be2c7c2007-02-10 01:46:02 -08001124 cmos_do_shutdown();
1125}
1126
Kay Sieversad28a072008-04-10 21:29:25 -07001127/* work with hotplug and coldplug */
1128MODULE_ALIAS("platform:rtc_cmos");
1129
David Brownell7be2c7c2007-02-10 01:46:02 -08001130static struct platform_driver cmos_platform_driver = {
1131 .remove = __exit_p(cmos_platform_remove),
1132 .shutdown = cmos_platform_shutdown,
1133 .driver = {
1134 .name = (char *) driver_name,
Paul Fox2fb08e62011-01-12 17:00:07 -08001135#ifdef CONFIG_PM
1136 .pm = &cmos_pm_ops,
1137#endif
Sachin Kamatc8a60462013-02-21 16:44:28 -08001138 .of_match_table = of_match_ptr(of_cmos_match),
David Brownell7be2c7c2007-02-10 01:46:02 -08001139 }
1140};
1141
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001142#ifdef CONFIG_PNP
1143static bool pnp_driver_registered;
1144#endif
1145static bool platform_driver_registered;
1146
David Brownell7be2c7c2007-02-10 01:46:02 -08001147static int __init cmos_init(void)
1148{
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001149 int retval = 0;
1150
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001151#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001152 retval = pnp_register_driver(&cmos_pnp_driver);
1153 if (retval == 0)
1154 pnp_driver_registered = true;
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001155#endif
1156
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001157 if (!cmos_rtc.dev) {
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001158 retval = platform_driver_probe(&cmos_platform_driver,
1159 cmos_platform_probe);
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001160 if (retval == 0)
1161 platform_driver_registered = true;
1162 }
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001163
1164 if (retval == 0)
1165 return 0;
1166
1167#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001168 if (pnp_driver_registered)
1169 pnp_unregister_driver(&cmos_pnp_driver);
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001170#endif
1171 return retval;
David Brownell7be2c7c2007-02-10 01:46:02 -08001172}
1173module_init(cmos_init);
1174
1175static void __exit cmos_exit(void)
1176{
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001177#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001178 if (pnp_driver_registered)
1179 pnp_unregister_driver(&cmos_pnp_driver);
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001180#endif
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001181 if (platform_driver_registered)
1182 platform_driver_unregister(&cmos_platform_driver);
David Brownell7be2c7c2007-02-10 01:46:02 -08001183}
1184module_exit(cmos_exit);
1185
1186
David Brownell7be2c7c2007-02-10 01:46:02 -08001187MODULE_AUTHOR("David Brownell");
1188MODULE_DESCRIPTION("Driver for PC-style 'CMOS' RTCs");
1189MODULE_LICENSE("GPL");