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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>
Jonathan Cameron5d2a5032009-01-06 14:42:12 -080037#include <linux/log2.h>
Paul Fox2fb08e62011-01-12 17:00:07 -080038#include <linux/pm.h>
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +010039#include <linux/of.h>
40#include <linux/of_platform.h>
Borislav Petkovd5a1c7e2013-07-20 19:00:23 +020041#include <linux/dmi.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);
Sachin Kamat5e8599d2013-07-03 15:05:45 -0700329 unsigned char mon, mday, hrs, min, sec, rtc_control;
David Brownell7be2c7c2007-02-10 01:46:02 -0800330
331 if (!is_valid_irq(cmos->irq))
332 return -EIO;
333
Zhao Yakui2b653e02008-04-15 14:34:29 -0700334 mon = t->time.tm_mon + 1;
David Brownell7be2c7c2007-02-10 01:46:02 -0800335 mday = t->time.tm_mday;
David Brownell7be2c7c2007-02-10 01:46:02 -0800336 hrs = t->time.tm_hour;
David Brownell7be2c7c2007-02-10 01:46:02 -0800337 min = t->time.tm_min;
David Brownell7be2c7c2007-02-10 01:46:02 -0800338 sec = t->time.tm_sec;
Arnaud Patard3804a892010-04-29 11:58:44 +0200339
340 rtc_control = CMOS_READ(RTC_CONTROL);
341 if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
342 /* Writing 0xff means "don't care" or "match all". */
343 mon = (mon <= 12) ? bin2bcd(mon) : 0xff;
344 mday = (mday >= 1 && mday <= 31) ? bin2bcd(mday) : 0xff;
345 hrs = (hrs < 24) ? bin2bcd(hrs) : 0xff;
346 min = (min < 60) ? bin2bcd(min) : 0xff;
347 sec = (sec < 60) ? bin2bcd(sec) : 0xff;
348 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800349
350 spin_lock_irq(&rtc_lock);
351
352 /* next rtc irq must not be from previous alarm setting */
David Brownell7e2a31d2008-07-23 21:30:47 -0700353 cmos_irq_disable(cmos, RTC_AIE);
David Brownell7be2c7c2007-02-10 01:46:02 -0800354
355 /* update alarm */
356 CMOS_WRITE(hrs, RTC_HOURS_ALARM);
357 CMOS_WRITE(min, RTC_MINUTES_ALARM);
358 CMOS_WRITE(sec, RTC_SECONDS_ALARM);
359
360 /* the system may support an "enhanced" alarm */
361 if (cmos->day_alrm) {
362 CMOS_WRITE(mday, cmos->day_alrm);
363 if (cmos->mon_alrm)
364 CMOS_WRITE(mon, cmos->mon_alrm);
365 }
366
David Brownell35d3fdd2008-07-23 21:30:43 -0700367 /* FIXME the HPET alarm glue currently ignores day_alrm
368 * and mon_alrm ...
369 */
370 hpet_set_alarm_time(t->time.tm_hour, t->time.tm_min, t->time.tm_sec);
371
David Brownell7e2a31d2008-07-23 21:30:47 -0700372 if (t->enabled)
373 cmos_irq_enable(cmos, RTC_AIE);
David Brownell7be2c7c2007-02-10 01:46:02 -0800374
375 spin_unlock_irq(&rtc_lock);
376
377 return 0;
378}
379
Borislav Petkovd5a1c7e2013-07-20 19:00:23 +0200380/*
381 * Do not disable RTC alarm on shutdown - workaround for b0rked BIOSes.
382 */
383static bool alarm_disable_quirk;
384
385static int __init set_alarm_disable_quirk(const struct dmi_system_id *id)
386{
387 alarm_disable_quirk = true;
388 pr_info("rtc-cmos: BIOS has alarm-disable quirk. ");
389 pr_info("RTC alarms disabled\n");
390 return 0;
391}
392
393static const struct dmi_system_id rtc_quirks[] __initconst = {
394 /* https://bugzilla.novell.com/show_bug.cgi?id=805740 */
395 {
396 .callback = set_alarm_disable_quirk,
397 .ident = "IBM Truman",
398 .matches = {
399 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
400 DMI_MATCH(DMI_PRODUCT_NAME, "4852570"),
401 },
402 },
403 /* https://bugzilla.novell.com/show_bug.cgi?id=812592 */
404 {
405 .callback = set_alarm_disable_quirk,
406 .ident = "Gigabyte GA-990XA-UD3",
407 .matches = {
408 DMI_MATCH(DMI_SYS_VENDOR,
409 "Gigabyte Technology Co., Ltd."),
410 DMI_MATCH(DMI_PRODUCT_NAME, "GA-990XA-UD3"),
411 },
412 },
413 /* http://permalink.gmane.org/gmane.linux.kernel/1604474 */
414 {
415 .callback = set_alarm_disable_quirk,
416 .ident = "Toshiba Satellite L300",
417 .matches = {
418 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
419 DMI_MATCH(DMI_PRODUCT_NAME, "Satellite L300"),
420 },
421 },
422 {}
423};
424
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800425static int cmos_alarm_irq_enable(struct device *dev, unsigned int enabled)
David Brownell7be2c7c2007-02-10 01:46:02 -0800426{
427 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownell7be2c7c2007-02-10 01:46:02 -0800428 unsigned long flags;
429
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800430 if (!is_valid_irq(cmos->irq))
431 return -EINVAL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800432
Borislav Petkovd5a1c7e2013-07-20 19:00:23 +0200433 if (alarm_disable_quirk)
434 return 0;
435
David Brownell7be2c7c2007-02-10 01:46:02 -0800436 spin_lock_irqsave(&rtc_lock, flags);
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800437
438 if (enabled)
David Brownell7e2a31d2008-07-23 21:30:47 -0700439 cmos_irq_enable(cmos, RTC_AIE);
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800440 else
441 cmos_irq_disable(cmos, RTC_AIE);
442
David Brownell7be2c7c2007-02-10 01:46:02 -0800443 spin_unlock_irqrestore(&rtc_lock, flags);
444 return 0;
445}
446
David Brownell7be2c7c2007-02-10 01:46:02 -0800447#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
448
449static int cmos_procfs(struct device *dev, struct seq_file *seq)
450{
451 struct cmos_rtc *cmos = dev_get_drvdata(dev);
452 unsigned char rtc_control, valid;
453
454 spin_lock_irq(&rtc_lock);
455 rtc_control = CMOS_READ(RTC_CONTROL);
456 valid = CMOS_READ(RTC_VALID);
457 spin_unlock_irq(&rtc_lock);
458
459 /* NOTE: at least ICH6 reports battery status using a different
460 * (non-RTC) bit; and SQWE is ignored on many current systems.
461 */
462 return seq_printf(seq,
463 "periodic_IRQ\t: %s\n"
464 "update_IRQ\t: %s\n"
David Brownellc8626a12008-02-23 15:23:44 -0800465 "HPET_emulated\t: %s\n"
David Brownell7be2c7c2007-02-10 01:46:02 -0800466 // "square_wave\t: %s\n"
Arnaud Patard3804a892010-04-29 11:58:44 +0200467 "BCD\t\t: %s\n"
David Brownell7be2c7c2007-02-10 01:46:02 -0800468 "DST_enable\t: %s\n"
469 "periodic_freq\t: %d\n"
470 "batt_status\t: %s\n",
471 (rtc_control & RTC_PIE) ? "yes" : "no",
472 (rtc_control & RTC_UIE) ? "yes" : "no",
David Brownellc8626a12008-02-23 15:23:44 -0800473 is_hpet_enabled() ? "yes" : "no",
David Brownell7be2c7c2007-02-10 01:46:02 -0800474 // (rtc_control & RTC_SQWE) ? "yes" : "no",
Arnaud Patard3804a892010-04-29 11:58:44 +0200475 (rtc_control & RTC_DM_BINARY) ? "no" : "yes",
David Brownell7be2c7c2007-02-10 01:46:02 -0800476 (rtc_control & RTC_DST_EN) ? "yes" : "no",
477 cmos->rtc->irq_freq,
478 (valid & RTC_VRT) ? "okay" : "dead");
479}
480
481#else
482#define cmos_procfs NULL
483#endif
484
485static const struct rtc_class_ops cmos_rtc_ops = {
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800486 .read_time = cmos_read_time,
487 .set_time = cmos_set_time,
488 .read_alarm = cmos_read_alarm,
489 .set_alarm = cmos_set_alarm,
490 .proc = cmos_procfs,
Herton Ronaldo Krzesinskia8462ef2009-12-15 16:45:56 -0800491 .alarm_irq_enable = cmos_alarm_irq_enable,
David Brownell7be2c7c2007-02-10 01:46:02 -0800492};
493
494/*----------------------------------------------------------------*/
495
David Brownelle07e2322008-02-06 01:38:43 -0800496/*
497 * All these chips have at least 64 bytes of address space, shared by
498 * RTC registers and NVRAM. Most of those bytes of NVRAM are used
499 * by boot firmware. Modern chips have 128 or 256 bytes.
500 */
501
502#define NVRAM_OFFSET (RTC_REG_D + 1)
503
504static ssize_t
Chris Wright2c3c8be2010-05-12 18:28:57 -0700505cmos_nvram_read(struct file *filp, struct kobject *kobj,
506 struct bin_attribute *attr,
David Brownelle07e2322008-02-06 01:38:43 -0800507 char *buf, loff_t off, size_t count)
508{
509 int retval;
510
511 if (unlikely(off >= attr->size))
512 return 0;
David Brownellc8fc40c2008-10-18 20:27:47 -0700513 if (unlikely(off < 0))
514 return -EINVAL;
David Brownelle07e2322008-02-06 01:38:43 -0800515 if ((off + count) > attr->size)
516 count = attr->size - off;
517
David Brownellc8fc40c2008-10-18 20:27:47 -0700518 off += NVRAM_OFFSET;
David Brownelle07e2322008-02-06 01:38:43 -0800519 spin_lock_irq(&rtc_lock);
David Brownellc8fc40c2008-10-18 20:27:47 -0700520 for (retval = 0; count; count--, off++, retval++) {
521 if (off < 128)
522 *buf++ = CMOS_READ(off);
523 else if (can_bank2)
524 *buf++ = cmos_read_bank2(off);
525 else
526 break;
527 }
David Brownelle07e2322008-02-06 01:38:43 -0800528 spin_unlock_irq(&rtc_lock);
529
530 return retval;
531}
532
533static ssize_t
Chris Wright2c3c8be2010-05-12 18:28:57 -0700534cmos_nvram_write(struct file *filp, struct kobject *kobj,
535 struct bin_attribute *attr,
David Brownelle07e2322008-02-06 01:38:43 -0800536 char *buf, loff_t off, size_t count)
537{
538 struct cmos_rtc *cmos;
539 int retval;
540
541 cmos = dev_get_drvdata(container_of(kobj, struct device, kobj));
542 if (unlikely(off >= attr->size))
543 return -EFBIG;
David Brownellc8fc40c2008-10-18 20:27:47 -0700544 if (unlikely(off < 0))
545 return -EINVAL;
David Brownelle07e2322008-02-06 01:38:43 -0800546 if ((off + count) > attr->size)
547 count = attr->size - off;
548
549 /* NOTE: on at least PCs and Ataris, the boot firmware uses a
550 * checksum on part of the NVRAM data. That's currently ignored
551 * here. If userspace is smart enough to know what fields of
552 * NVRAM to update, updating checksums is also part of its job.
553 */
David Brownellc8fc40c2008-10-18 20:27:47 -0700554 off += NVRAM_OFFSET;
David Brownelle07e2322008-02-06 01:38:43 -0800555 spin_lock_irq(&rtc_lock);
David Brownellc8fc40c2008-10-18 20:27:47 -0700556 for (retval = 0; count; count--, off++, retval++) {
David Brownelle07e2322008-02-06 01:38:43 -0800557 /* don't trash RTC registers */
558 if (off == cmos->day_alrm
559 || off == cmos->mon_alrm
560 || off == cmos->century)
561 buf++;
David Brownellc8fc40c2008-10-18 20:27:47 -0700562 else if (off < 128)
David Brownelle07e2322008-02-06 01:38:43 -0800563 CMOS_WRITE(*buf++, off);
David Brownellc8fc40c2008-10-18 20:27:47 -0700564 else if (can_bank2)
565 cmos_write_bank2(*buf++, off);
566 else
567 break;
David Brownelle07e2322008-02-06 01:38:43 -0800568 }
569 spin_unlock_irq(&rtc_lock);
570
571 return retval;
572}
573
574static struct bin_attribute nvram = {
575 .attr = {
576 .name = "nvram",
577 .mode = S_IRUGO | S_IWUSR,
David Brownelle07e2322008-02-06 01:38:43 -0800578 },
579
580 .read = cmos_nvram_read,
581 .write = cmos_nvram_write,
582 /* size gets set up later */
583};
584
585/*----------------------------------------------------------------*/
586
David Brownell7be2c7c2007-02-10 01:46:02 -0800587static struct cmos_rtc cmos_rtc;
588
589static irqreturn_t cmos_interrupt(int irq, void *p)
590{
591 u8 irqstat;
David Brownell8a0bdfd2008-02-06 01:38:45 -0800592 u8 rtc_control;
David Brownell7be2c7c2007-02-10 01:46:02 -0800593
594 spin_lock(&rtc_lock);
David Brownell35d3fdd2008-07-23 21:30:43 -0700595
596 /* When the HPET interrupt handler calls us, the interrupt
597 * status is passed as arg1 instead of the irq number. But
598 * always clear irq status, even when HPET is in the way.
599 *
600 * Note that HPET and RTC are almost certainly out of phase,
601 * giving different IRQ status ...
Bernhard Walle9d8af782008-02-06 01:38:52 -0800602 */
David Brownell35d3fdd2008-07-23 21:30:43 -0700603 irqstat = CMOS_READ(RTC_INTR_FLAGS);
604 rtc_control = CMOS_READ(RTC_CONTROL);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800605 if (is_hpet_enabled())
606 irqstat = (unsigned long)irq & 0xF0;
Derek Basehore998a0602013-07-03 15:07:54 -0700607
608 /* If we were suspended, RTC_CONTROL may not be accurate since the
609 * bios may have cleared it.
610 */
611 if (!cmos_rtc.suspend_ctrl)
612 irqstat &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
613 else
614 irqstat &= (cmos_rtc.suspend_ctrl & RTC_IRQMASK) | RTC_IRQF;
David Brownell8a0bdfd2008-02-06 01:38:45 -0800615
616 /* All Linux RTC alarms should be treated as if they were oneshot.
617 * Similar code may be needed in system wakeup paths, in case the
618 * alarm woke the system.
619 */
620 if (irqstat & RTC_AIE) {
Derek Basehore998a0602013-07-03 15:07:54 -0700621 cmos_rtc.suspend_ctrl &= ~RTC_AIE;
David Brownell8a0bdfd2008-02-06 01:38:45 -0800622 rtc_control &= ~RTC_AIE;
623 CMOS_WRITE(rtc_control, RTC_CONTROL);
David Brownell35d3fdd2008-07-23 21:30:43 -0700624 hpet_mask_rtc_irq_bit(RTC_AIE);
David Brownell8a0bdfd2008-02-06 01:38:45 -0800625 CMOS_READ(RTC_INTR_FLAGS);
626 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800627 spin_unlock(&rtc_lock);
628
David Brownellbcd9b892007-04-01 23:49:47 -0700629 if (is_intr(irqstat)) {
David Brownell7be2c7c2007-02-10 01:46:02 -0800630 rtc_update_irq(p, 1, irqstat);
631 return IRQ_HANDLED;
632 } else
633 return IRQ_NONE;
634}
635
Marko Vrh41ac8df2007-05-08 00:34:09 -0700636#ifdef CONFIG_PNP
David Brownell7be2c7c2007-02-10 01:46:02 -0800637#define INITSECTION
638
639#else
David Brownell7be2c7c2007-02-10 01:46:02 -0800640#define INITSECTION __init
641#endif
642
643static int INITSECTION
644cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
645{
Jingoo Han97a92e72013-11-12 15:10:38 -0800646 struct cmos_rtc_board_info *info = dev_get_platdata(dev);
David Brownell7be2c7c2007-02-10 01:46:02 -0800647 int retval = 0;
648 unsigned char rtc_control;
David Brownelle07e2322008-02-06 01:38:43 -0800649 unsigned address_space;
David Brownell7be2c7c2007-02-10 01:46:02 -0800650
651 /* there can be only one ... */
652 if (cmos_rtc.dev)
653 return -EBUSY;
654
655 if (!ports)
656 return -ENODEV;
657
David Brownell05440df2007-10-16 01:28:21 -0700658 /* Claim I/O ports ASAP, minimizing conflict with legacy driver.
659 *
660 * REVISIT non-x86 systems may instead use memory space resources
661 * (needing ioremap etc), not i/o space resources like this ...
662 */
663 ports = request_region(ports->start,
Joe Perches28f65c112011-06-09 09:13:32 -0700664 resource_size(ports),
David Brownell05440df2007-10-16 01:28:21 -0700665 driver_name);
666 if (!ports) {
667 dev_dbg(dev, "i/o registers already in use\n");
668 return -EBUSY;
669 }
670
David Brownell7be2c7c2007-02-10 01:46:02 -0800671 cmos_rtc.irq = rtc_irq;
672 cmos_rtc.iomem = ports;
673
David Brownelle07e2322008-02-06 01:38:43 -0800674 /* Heuristic to deduce NVRAM size ... do what the legacy NVRAM
675 * driver did, but don't reject unknown configs. Old hardware
David Brownellc8fc40c2008-10-18 20:27:47 -0700676 * won't address 128 bytes. Newer chips have multiple banks,
677 * though they may not be listed in one I/O resource.
David Brownelle07e2322008-02-06 01:38:43 -0800678 */
679#if defined(CONFIG_ATARI)
680 address_space = 64;
Wu Zhangjin95abd0d2009-11-05 09:21:54 +0800681#elif defined(__i386__) || defined(__x86_64__) || defined(__arm__) \
Srikanth Krishnakar8cb7c712010-10-14 04:03:35 +0000682 || defined(__sparc__) || defined(__mips__) \
683 || defined(__powerpc__)
David Brownelle07e2322008-02-06 01:38:43 -0800684 address_space = 128;
685#else
686#warning Assuming 128 bytes of RTC+NVRAM address space, not 64 bytes.
687 address_space = 128;
688#endif
David Brownellc8fc40c2008-10-18 20:27:47 -0700689 if (can_bank2 && ports->end > (ports->start + 1))
690 address_space = 256;
David Brownelle07e2322008-02-06 01:38:43 -0800691
David Brownell87ac84f2007-05-08 00:34:00 -0700692 /* For ACPI systems extension info comes from the FADT. On others,
693 * board specific setup provides it as appropriate. Systems where
694 * the alarm IRQ isn't automatically a wakeup IRQ (like ACPI, and
695 * some almost-clones) can provide hooks to make that behave.
David Brownelle07e2322008-02-06 01:38:43 -0800696 *
697 * Note that ACPI doesn't preclude putting these registers into
698 * "extended" areas of the chip, including some that we won't yet
699 * expect CMOS_READ and friends to handle.
David Brownell7be2c7c2007-02-10 01:46:02 -0800700 */
701 if (info) {
David Brownelle07e2322008-02-06 01:38:43 -0800702 if (info->rtc_day_alarm && info->rtc_day_alarm < 128)
703 cmos_rtc.day_alrm = info->rtc_day_alarm;
704 if (info->rtc_mon_alarm && info->rtc_mon_alarm < 128)
705 cmos_rtc.mon_alrm = info->rtc_mon_alarm;
706 if (info->rtc_century && info->rtc_century < 128)
707 cmos_rtc.century = info->rtc_century;
David Brownell87ac84f2007-05-08 00:34:00 -0700708
709 if (info->wake_on && info->wake_off) {
710 cmos_rtc.wake_on = info->wake_on;
711 cmos_rtc.wake_off = info->wake_off;
712 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800713 }
714
Dan Carpenter6ba8bcd2010-05-24 14:33:49 -0700715 cmos_rtc.dev = dev;
716 dev_set_drvdata(dev, &cmos_rtc);
717
David Brownell7be2c7c2007-02-10 01:46:02 -0800718 cmos_rtc.rtc = rtc_device_register(driver_name, dev,
719 &cmos_rtc_ops, THIS_MODULE);
David Brownell05440df2007-10-16 01:28:21 -0700720 if (IS_ERR(cmos_rtc.rtc)) {
721 retval = PTR_ERR(cmos_rtc.rtc);
722 goto cleanup0;
723 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800724
Kay Sieversd4afc762009-01-06 14:42:11 -0800725 rename_region(ports, dev_name(&cmos_rtc.rtc->dev));
David Brownell7be2c7c2007-02-10 01:46:02 -0800726
727 spin_lock_irq(&rtc_lock);
728
729 /* force periodic irq to CMOS reset default of 1024Hz;
730 *
731 * REVISIT it's been reported that at least one x86_64 ALI mobo
732 * doesn't use 32KHz here ... for portability we might need to
733 * do something about other clock frequencies.
734 */
David Brownell7be2c7c2007-02-10 01:46:02 -0800735 cmos_rtc.rtc->irq_freq = 1024;
David Brownell35d3fdd2008-07-23 21:30:43 -0700736 hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq);
737 CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
David Brownell7be2c7c2007-02-10 01:46:02 -0800738
David Brownell7e2a31d2008-07-23 21:30:47 -0700739 /* disable irqs */
740 cmos_irq_disable(&cmos_rtc, RTC_PIE | RTC_AIE | RTC_UIE);
David Brownell35d3fdd2008-07-23 21:30:43 -0700741
David Brownell7e2a31d2008-07-23 21:30:47 -0700742 rtc_control = CMOS_READ(RTC_CONTROL);
David Brownell7be2c7c2007-02-10 01:46:02 -0800743
744 spin_unlock_irq(&rtc_lock);
745
Arnaud Patard3804a892010-04-29 11:58:44 +0200746 /* FIXME:
David Brownell7be2c7c2007-02-10 01:46:02 -0800747 * <asm-generic/rtc.h> doesn't know 12-hour mode either.
748 */
Sachin Kamat5e8599d2013-07-03 15:05:45 -0700749 if (is_valid_irq(rtc_irq) && !(rtc_control & RTC_24H)) {
Arnaud Patard3804a892010-04-29 11:58:44 +0200750 dev_warn(dev, "only 24-hr supported\n");
David Brownell7be2c7c2007-02-10 01:46:02 -0800751 retval = -ENXIO;
752 goto cleanup1;
753 }
754
Bernhard Walle9d8af782008-02-06 01:38:52 -0800755 if (is_valid_irq(rtc_irq)) {
756 irq_handler_t rtc_cmos_int_handler;
757
758 if (is_hpet_enabled()) {
Bernhard Walle9d8af782008-02-06 01:38:52 -0800759 rtc_cmos_int_handler = hpet_rtc_interrupt;
Andrew Morton24b34472014-01-23 15:55:15 -0800760 retval = hpet_register_irq_handler(cmos_interrupt);
761 if (retval) {
Jingoo Hanee443352013-02-21 16:45:34 -0800762 dev_warn(dev, "hpet_register_irq_handler "
Bernhard Walle9d8af782008-02-06 01:38:52 -0800763 " failed in rtc_init().");
764 goto cleanup1;
765 }
766 } else
767 rtc_cmos_int_handler = cmos_interrupt;
768
769 retval = request_irq(rtc_irq, rtc_cmos_int_handler,
Yong Zhang2f6e5f92012-03-23 15:02:34 -0700770 0, dev_name(&cmos_rtc.rtc->dev),
David Brownellab6a2d72007-05-08 00:33:30 -0700771 cmos_rtc.rtc);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800772 if (retval < 0) {
773 dev_dbg(dev, "IRQ %d is already in use\n", rtc_irq);
774 goto cleanup1;
775 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800776 }
Bernhard Walle9d8af782008-02-06 01:38:52 -0800777 hpet_rtc_timer_init();
David Brownell7be2c7c2007-02-10 01:46:02 -0800778
David Brownelle07e2322008-02-06 01:38:43 -0800779 /* export at least the first block of NVRAM */
780 nvram.size = address_space - NVRAM_OFFSET;
781 retval = sysfs_create_bin_file(&dev->kobj, &nvram);
782 if (retval < 0) {
783 dev_dbg(dev, "can't create nvram file? %d\n", retval);
784 goto cleanup2;
785 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800786
Jingoo Hanee443352013-02-21 16:45:34 -0800787 dev_info(dev, "%s%s, %zd bytes nvram%s\n",
Krzysztof Halasa6d029b62009-04-21 12:24:49 -0700788 !is_valid_irq(rtc_irq) ? "no alarms" :
789 cmos_rtc.mon_alrm ? "alarms up to one year" :
790 cmos_rtc.day_alrm ? "alarms up to one month" :
791 "alarms up to one day",
792 cmos_rtc.century ? ", y3k" : "",
793 nvram.size,
794 is_hpet_enabled() ? ", hpet irqs" : "");
David Brownell7be2c7c2007-02-10 01:46:02 -0800795
796 return 0;
797
David Brownelle07e2322008-02-06 01:38:43 -0800798cleanup2:
799 if (is_valid_irq(rtc_irq))
800 free_irq(rtc_irq, cmos_rtc.rtc);
David Brownell7be2c7c2007-02-10 01:46:02 -0800801cleanup1:
David Brownell05440df2007-10-16 01:28:21 -0700802 cmos_rtc.dev = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800803 rtc_device_unregister(cmos_rtc.rtc);
David Brownell05440df2007-10-16 01:28:21 -0700804cleanup0:
Joe Perches28f65c112011-06-09 09:13:32 -0700805 release_region(ports->start, resource_size(ports));
David Brownell7be2c7c2007-02-10 01:46:02 -0800806 return retval;
807}
808
809static void cmos_do_shutdown(void)
810{
David Brownell7be2c7c2007-02-10 01:46:02 -0800811 spin_lock_irq(&rtc_lock);
David Brownell7e2a31d2008-07-23 21:30:47 -0700812 cmos_irq_disable(&cmos_rtc, RTC_IRQMASK);
David Brownell7be2c7c2007-02-10 01:46:02 -0800813 spin_unlock_irq(&rtc_lock);
814}
815
816static void __exit cmos_do_remove(struct device *dev)
817{
818 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownell05440df2007-10-16 01:28:21 -0700819 struct resource *ports;
David Brownell7be2c7c2007-02-10 01:46:02 -0800820
821 cmos_do_shutdown();
822
David Brownelle07e2322008-02-06 01:38:43 -0800823 sysfs_remove_bin_file(&dev->kobj, &nvram);
824
Bernhard Walle9d8af782008-02-06 01:38:52 -0800825 if (is_valid_irq(cmos->irq)) {
David Brownell05440df2007-10-16 01:28:21 -0700826 free_irq(cmos->irq, cmos->rtc);
Bernhard Walle9d8af782008-02-06 01:38:52 -0800827 hpet_unregister_irq_handler(cmos_interrupt);
828 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800829
David Brownell05440df2007-10-16 01:28:21 -0700830 rtc_device_unregister(cmos->rtc);
831 cmos->rtc = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800832
David Brownell05440df2007-10-16 01:28:21 -0700833 ports = cmos->iomem;
Joe Perches28f65c112011-06-09 09:13:32 -0700834 release_region(ports->start, resource_size(ports));
David Brownell05440df2007-10-16 01:28:21 -0700835 cmos->iomem = NULL;
836
837 cmos->dev = NULL;
David Brownell7be2c7c2007-02-10 01:46:02 -0800838}
839
840#ifdef CONFIG_PM
841
Paul Fox2fb08e62011-01-12 17:00:07 -0800842static int cmos_suspend(struct device *dev)
David Brownell7be2c7c2007-02-10 01:46:02 -0800843{
844 struct cmos_rtc *cmos = dev_get_drvdata(dev);
David Brownellbcd9b892007-04-01 23:49:47 -0700845 unsigned char tmp;
David Brownell7be2c7c2007-02-10 01:46:02 -0800846
847 /* only the alarm might be a wakeup event source */
848 spin_lock_irq(&rtc_lock);
849 cmos->suspend_ctrl = tmp = CMOS_READ(RTC_CONTROL);
850 if (tmp & (RTC_PIE|RTC_AIE|RTC_UIE)) {
David Brownell35d3fdd2008-07-23 21:30:43 -0700851 unsigned char mask;
David Brownellbcd9b892007-04-01 23:49:47 -0700852
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700853 if (device_may_wakeup(dev))
David Brownell35d3fdd2008-07-23 21:30:43 -0700854 mask = RTC_IRQMASK & ~RTC_AIE;
David Brownell7be2c7c2007-02-10 01:46:02 -0800855 else
David Brownell35d3fdd2008-07-23 21:30:43 -0700856 mask = RTC_IRQMASK;
857 tmp &= ~mask;
David Brownell7be2c7c2007-02-10 01:46:02 -0800858 CMOS_WRITE(tmp, RTC_CONTROL);
Derek Basehoree0057152013-04-29 16:20:23 -0700859 hpet_mask_rtc_irq_bit(mask);
David Brownell35d3fdd2008-07-23 21:30:43 -0700860
David Brownell7e2a31d2008-07-23 21:30:47 -0700861 cmos_checkintr(cmos, tmp);
David Brownellbcd9b892007-04-01 23:49:47 -0700862 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800863 spin_unlock_irq(&rtc_lock);
864
David Brownell87ac84f2007-05-08 00:34:00 -0700865 if (tmp & RTC_AIE) {
866 cmos->enabled_wake = 1;
867 if (cmos->wake_on)
868 cmos->wake_on(dev);
869 else
870 enable_irq_wake(cmos->irq);
871 }
David Brownell7be2c7c2007-02-10 01:46:02 -0800872
Jingoo Hanee443352013-02-21 16:45:34 -0800873 dev_dbg(dev, "suspend%s, ctrl %02x\n",
David Brownell7be2c7c2007-02-10 01:46:02 -0800874 (tmp & RTC_AIE) ? ", alarm may wake" : "",
875 tmp);
876
877 return 0;
878}
879
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700880/* We want RTC alarms to wake us from e.g. ACPI G2/S5 "soft off", even
881 * after a detour through G3 "mechanical off", although the ACPI spec
882 * says wakeup should only work from G1/S4 "hibernate". To most users,
883 * distinctions between S4 and S5 are pointless. So when the hardware
884 * allows, don't draw that distinction.
885 */
886static inline int cmos_poweroff(struct device *dev)
887{
Paul Fox2fb08e62011-01-12 17:00:07 -0800888 return cmos_suspend(dev);
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700889}
890
David Brownell7be2c7c2007-02-10 01:46:02 -0800891static int cmos_resume(struct device *dev)
892{
893 struct cmos_rtc *cmos = dev_get_drvdata(dev);
Derek Basehore998a0602013-07-03 15:07:54 -0700894 unsigned char tmp;
David Brownell7be2c7c2007-02-10 01:46:02 -0800895
Derek Basehore998a0602013-07-03 15:07:54 -0700896 if (cmos->enabled_wake) {
897 if (cmos->wake_off)
898 cmos->wake_off(dev);
899 else
900 disable_irq_wake(cmos->irq);
901 cmos->enabled_wake = 0;
902 }
903
904 spin_lock_irq(&rtc_lock);
905 tmp = cmos->suspend_ctrl;
906 cmos->suspend_ctrl = 0;
David Brownell7be2c7c2007-02-10 01:46:02 -0800907 /* re-enable any irqs previously active */
David Brownell35d3fdd2008-07-23 21:30:43 -0700908 if (tmp & RTC_IRQMASK) {
909 unsigned char mask;
David Brownell7be2c7c2007-02-10 01:46:02 -0800910
Derek Basehoreebf8d6c2013-06-12 14:04:45 -0700911 if (device_may_wakeup(dev))
912 hpet_rtc_timer_init();
913
David Brownell35d3fdd2008-07-23 21:30:43 -0700914 do {
915 CMOS_WRITE(tmp, RTC_CONTROL);
916 hpet_set_rtc_irq_bit(tmp & RTC_IRQMASK);
917
918 mask = CMOS_READ(RTC_INTR_FLAGS);
919 mask &= (tmp & RTC_IRQMASK) | RTC_IRQF;
David Brownell7e2a31d2008-07-23 21:30:47 -0700920 if (!is_hpet_enabled() || !is_intr(mask))
David Brownell35d3fdd2008-07-23 21:30:43 -0700921 break;
922
923 /* force one-shot behavior if HPET blocked
924 * the wake alarm's irq
925 */
926 rtc_update_irq(cmos->rtc, 1, mask);
927 tmp &= ~RTC_AIE;
928 hpet_mask_rtc_irq_bit(RTC_AIE);
929 } while (mask & RTC_AIE);
David Brownell7be2c7c2007-02-10 01:46:02 -0800930 }
Derek Basehore998a0602013-07-03 15:07:54 -0700931 spin_unlock_irq(&rtc_lock);
David Brownell7be2c7c2007-02-10 01:46:02 -0800932
Jingoo Hanee443352013-02-21 16:45:34 -0800933 dev_dbg(dev, "resume, ctrl %02x\n", tmp);
David Brownell7be2c7c2007-02-10 01:46:02 -0800934
935 return 0;
936}
937
Paul Fox2fb08e62011-01-12 17:00:07 -0800938static SIMPLE_DEV_PM_OPS(cmos_pm_ops, cmos_suspend, cmos_resume);
939
David Brownell7be2c7c2007-02-10 01:46:02 -0800940#else
Rafael J. Wysocki74c46332008-09-02 14:36:11 -0700941
942static inline int cmos_poweroff(struct device *dev)
943{
944 return -ENOSYS;
945}
946
David Brownell7be2c7c2007-02-10 01:46:02 -0800947#endif
948
949/*----------------------------------------------------------------*/
950
David Brownelle07e2322008-02-06 01:38:43 -0800951/* On non-x86 systems, a "CMOS" RTC lives most naturally on platform_bus.
952 * ACPI systems always list these as PNPACPI devices, and pre-ACPI PCs
953 * probably list them in similar PNPBIOS tables; so PNP is more common.
954 *
955 * We don't use legacy "poke at the hardware" probing. Ancient PCs that
956 * predate even PNPBIOS should set up platform_bus devices.
David Brownell7be2c7c2007-02-10 01:46:02 -0800957 */
958
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600959#ifdef CONFIG_ACPI
960
961#include <linux/acpi.h>
962
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600963static u32 rtc_handler(void *context)
964{
Daniel Drakeb2201e52012-05-18 22:59:41 +0200965 struct device *dev = context;
966
967 pm_wakeup_event(dev, 0);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600968 acpi_clear_event(ACPI_EVENT_RTC);
969 acpi_disable_event(ACPI_EVENT_RTC, 0);
970 return ACPI_INTERRUPT_HANDLED;
971}
972
Daniel Drakeb2201e52012-05-18 22:59:41 +0200973static inline void rtc_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600974{
Daniel Drakeb2201e52012-05-18 22:59:41 +0200975 acpi_install_fixed_event_handler(ACPI_EVENT_RTC, rtc_handler, dev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600976 /*
977 * After the RTC handler is installed, the Fixed_RTC event should
978 * be disabled. Only when the RTC alarm is set will it be enabled.
979 */
980 acpi_clear_event(ACPI_EVENT_RTC);
981 acpi_disable_event(ACPI_EVENT_RTC, 0);
982}
983
984static void rtc_wake_on(struct device *dev)
985{
986 acpi_clear_event(ACPI_EVENT_RTC);
987 acpi_enable_event(ACPI_EVENT_RTC, 0);
988}
989
990static void rtc_wake_off(struct device *dev)
991{
992 acpi_disable_event(ACPI_EVENT_RTC, 0);
993}
Bjorn Helgaasa474aae2008-10-14 13:50:21 -0600994
995/* Every ACPI platform has a mc146818 compatible "cmos rtc". Here we find
996 * its device node and pass extra config data. This helps its driver use
997 * capabilities that the now-obsolete mc146818 didn't have, and informs it
998 * that this board's RTC is wakeup-capable (per ACPI spec).
999 */
1000static struct cmos_rtc_board_info acpi_rtc_info;
1001
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -08001002static void cmos_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001003{
1004 if (acpi_disabled)
1005 return;
1006
Daniel Drakeb2201e52012-05-18 22:59:41 +02001007 rtc_wake_setup(dev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001008 acpi_rtc_info.wake_on = rtc_wake_on;
1009 acpi_rtc_info.wake_off = rtc_wake_off;
1010
1011 /* workaround bug in some ACPI tables */
1012 if (acpi_gbl_FADT.month_alarm && !acpi_gbl_FADT.day_alarm) {
1013 dev_dbg(dev, "bogus FADT month_alarm (%d)\n",
1014 acpi_gbl_FADT.month_alarm);
1015 acpi_gbl_FADT.month_alarm = 0;
1016 }
1017
1018 acpi_rtc_info.rtc_day_alarm = acpi_gbl_FADT.day_alarm;
1019 acpi_rtc_info.rtc_mon_alarm = acpi_gbl_FADT.month_alarm;
1020 acpi_rtc_info.rtc_century = acpi_gbl_FADT.century;
1021
1022 /* NOTE: S4_RTC_WAKE is NOT currently useful to Linux */
1023 if (acpi_gbl_FADT.flags & ACPI_FADT_S4_RTC_WAKE)
1024 dev_info(dev, "RTC can wake from S4\n");
1025
1026 dev->platform_data = &acpi_rtc_info;
1027
1028 /* RTC always wakes from S1/S2/S3, and often S4/STD */
1029 device_init_wakeup(dev, 1);
1030}
1031
1032#else
1033
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -08001034static void cmos_wake_setup(struct device *dev)
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001035{
1036}
1037
1038#endif
1039
Marko Vrh41ac8df2007-05-08 00:34:09 -07001040#ifdef CONFIG_PNP
David Brownell7be2c7c2007-02-10 01:46:02 -08001041
1042#include <linux/pnp.h>
1043
Greg Kroah-Hartman5a167f42012-12-21 13:09:38 -08001044static int cmos_pnp_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
David Brownell7be2c7c2007-02-10 01:46:02 -08001045{
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001046 cmos_wake_setup(&pnp->dev);
1047
Sachin Kamat5e8599d2013-07-03 15:05:45 -07001048 if (pnp_port_start(pnp, 0) == 0x70 && !pnp_irq_valid(pnp, 0))
Matthew Garrett6cd8fa82007-06-01 00:46:51 -07001049 /* Some machines contain a PNP entry for the RTC, but
1050 * don't define the IRQ. It should always be safe to
1051 * hardcode it in these cases
1052 */
Bjorn Helgaas8766ad02008-04-28 16:34:27 -06001053 return cmos_do_probe(&pnp->dev,
1054 pnp_get_resource(pnp, IORESOURCE_IO, 0), 8);
Matthew Garrett6cd8fa82007-06-01 00:46:51 -07001055 else
1056 return cmos_do_probe(&pnp->dev,
Bjorn Helgaas8766ad02008-04-28 16:34:27 -06001057 pnp_get_resource(pnp, IORESOURCE_IO, 0),
1058 pnp_irq(pnp, 0));
David Brownell7be2c7c2007-02-10 01:46:02 -08001059}
1060
1061static void __exit cmos_pnp_remove(struct pnp_dev *pnp)
1062{
1063 cmos_do_remove(&pnp->dev);
1064}
1065
OGAWA Hirofumi004731b2010-01-08 14:43:11 -08001066static void cmos_pnp_shutdown(struct pnp_dev *pnp)
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001067{
OGAWA Hirofumi004731b2010-01-08 14:43:11 -08001068 if (system_state == SYSTEM_POWER_OFF && !cmos_poweroff(&pnp->dev))
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001069 return;
1070
1071 cmos_do_shutdown();
1072}
David Brownell7be2c7c2007-02-10 01:46:02 -08001073
1074static const struct pnp_device_id rtc_ids[] = {
1075 { .id = "PNP0b00", },
1076 { .id = "PNP0b01", },
1077 { .id = "PNP0b02", },
1078 { },
1079};
1080MODULE_DEVICE_TABLE(pnp, rtc_ids);
1081
1082static struct pnp_driver cmos_pnp_driver = {
1083 .name = (char *) driver_name,
1084 .id_table = rtc_ids,
1085 .probe = cmos_pnp_probe,
1086 .remove = __exit_p(cmos_pnp_remove),
OGAWA Hirofumi004731b2010-01-08 14:43:11 -08001087 .shutdown = cmos_pnp_shutdown,
David Brownell7be2c7c2007-02-10 01:46:02 -08001088
1089 /* flag ensures resume() gets called, and stops syslog spam */
1090 .flags = PNP_DRIVER_RES_DO_NOT_CHANGE,
Shuah Khana8a38082013-09-11 14:23:11 -07001091#ifdef CONFIG_PM_SLEEP
1092 .driver = {
1093 .pm = &cmos_pm_ops,
1094 },
1095#endif
David Brownell7be2c7c2007-02-10 01:46:02 -08001096};
1097
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001098#endif /* CONFIG_PNP */
David Brownell7be2c7c2007-02-10 01:46:02 -08001099
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001100#ifdef CONFIG_OF
1101static const struct of_device_id of_cmos_match[] = {
1102 {
1103 .compatible = "motorola,mc146818",
1104 },
1105 { },
1106};
1107MODULE_DEVICE_TABLE(of, of_cmos_match);
1108
1109static __init void cmos_of_init(struct platform_device *pdev)
1110{
1111 struct device_node *node = pdev->dev.of_node;
1112 struct rtc_time time;
1113 int ret;
1114 const __be32 *val;
1115
1116 if (!node)
1117 return;
1118
1119 val = of_get_property(node, "ctrl-reg", NULL);
1120 if (val)
1121 CMOS_WRITE(be32_to_cpup(val), RTC_CONTROL);
1122
1123 val = of_get_property(node, "freq-reg", NULL);
1124 if (val)
1125 CMOS_WRITE(be32_to_cpup(val), RTC_FREQ_SELECT);
1126
1127 get_rtc_time(&time);
1128 ret = rtc_valid_tm(&time);
1129 if (ret) {
1130 struct rtc_time def_time = {
1131 .tm_year = 1,
1132 .tm_mday = 1,
1133 };
1134 set_rtc_time(&def_time);
1135 }
1136}
1137#else
1138static inline void cmos_of_init(struct platform_device *pdev) {}
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001139#endif
David Brownell7be2c7c2007-02-10 01:46:02 -08001140/*----------------------------------------------------------------*/
1141
Marko Vrh41ac8df2007-05-08 00:34:09 -07001142/* Platform setup should have set up an RTC device, when PNP is
David Brownellbcd9b892007-04-01 23:49:47 -07001143 * unavailable ... this could happen even on (older) PCs.
David Brownell7be2c7c2007-02-10 01:46:02 -08001144 */
1145
1146static int __init cmos_platform_probe(struct platform_device *pdev)
1147{
Sebastian Andrzej Siewior3bcbaf62011-02-22 21:07:46 +01001148 cmos_of_init(pdev);
Bjorn Helgaasa474aae2008-10-14 13:50:21 -06001149 cmos_wake_setup(&pdev->dev);
David Brownell7be2c7c2007-02-10 01:46:02 -08001150 return cmos_do_probe(&pdev->dev,
1151 platform_get_resource(pdev, IORESOURCE_IO, 0),
1152 platform_get_irq(pdev, 0));
1153}
1154
1155static int __exit cmos_platform_remove(struct platform_device *pdev)
1156{
1157 cmos_do_remove(&pdev->dev);
1158 return 0;
1159}
1160
1161static void cmos_platform_shutdown(struct platform_device *pdev)
1162{
Rafael J. Wysocki74c46332008-09-02 14:36:11 -07001163 if (system_state == SYSTEM_POWER_OFF && !cmos_poweroff(&pdev->dev))
1164 return;
1165
David Brownell7be2c7c2007-02-10 01:46:02 -08001166 cmos_do_shutdown();
1167}
1168
Kay Sieversad28a072008-04-10 21:29:25 -07001169/* work with hotplug and coldplug */
1170MODULE_ALIAS("platform:rtc_cmos");
1171
David Brownell7be2c7c2007-02-10 01:46:02 -08001172static struct platform_driver cmos_platform_driver = {
1173 .remove = __exit_p(cmos_platform_remove),
1174 .shutdown = cmos_platform_shutdown,
1175 .driver = {
Geert Uytterhoevenc823a202014-01-23 15:55:11 -08001176 .name = driver_name,
Paul Fox2fb08e62011-01-12 17:00:07 -08001177#ifdef CONFIG_PM
1178 .pm = &cmos_pm_ops,
1179#endif
Sachin Kamatc8a60462013-02-21 16:44:28 -08001180 .of_match_table = of_match_ptr(of_cmos_match),
David Brownell7be2c7c2007-02-10 01:46:02 -08001181 }
1182};
1183
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001184#ifdef CONFIG_PNP
1185static bool pnp_driver_registered;
1186#endif
1187static bool platform_driver_registered;
1188
David Brownell7be2c7c2007-02-10 01:46:02 -08001189static int __init cmos_init(void)
1190{
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001191 int retval = 0;
1192
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001193#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001194 retval = pnp_register_driver(&cmos_pnp_driver);
1195 if (retval == 0)
1196 pnp_driver_registered = true;
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001197#endif
1198
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001199 if (!cmos_rtc.dev) {
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001200 retval = platform_driver_probe(&cmos_platform_driver,
1201 cmos_platform_probe);
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001202 if (retval == 0)
1203 platform_driver_registered = true;
1204 }
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001205
Borislav Petkovd5a1c7e2013-07-20 19:00:23 +02001206 dmi_check_system(rtc_quirks);
1207
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001208 if (retval == 0)
1209 return 0;
1210
1211#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001212 if (pnp_driver_registered)
1213 pnp_unregister_driver(&cmos_pnp_driver);
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001214#endif
1215 return retval;
David Brownell7be2c7c2007-02-10 01:46:02 -08001216}
1217module_init(cmos_init);
1218
1219static void __exit cmos_exit(void)
1220{
Stas Sergeev1da2e3d2008-06-12 15:21:54 -07001221#ifdef CONFIG_PNP
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001222 if (pnp_driver_registered)
1223 pnp_unregister_driver(&cmos_pnp_driver);
Bjorn Helgaas72f22b12008-10-14 17:01:59 -06001224#endif
Thadeu Lima de Souza Cascardo65909812009-07-29 15:02:13 -07001225 if (platform_driver_registered)
1226 platform_driver_unregister(&cmos_platform_driver);
David Brownell7be2c7c2007-02-10 01:46:02 -08001227}
1228module_exit(cmos_exit);
1229
1230
David Brownell7be2c7c2007-02-10 01:46:02 -08001231MODULE_AUTHOR("David Brownell");
1232MODULE_DESCRIPTION("Driver for PC-style 'CMOS' RTCs");
1233MODULE_LICENSE("GPL");