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[PATCH] IPMI oops fix
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / char / rtc.c
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1da177e4
LT		 1/*
2 * Real Time Clock interface for Linux
3 *
4 * Copyright (C) 1996 Paul Gortmaker
5 *
6 * This driver allows use of the real time clock (built into
7 * nearly all computers) from user space. It exports the /dev/rtc
8 * interface supporting various ioctl() and also the
9 * /proc/driver/rtc pseudo-file for status information.
10 *
11 * The ioctls can be used to set the interrupt behaviour and
12 * generation rate from the RTC via IRQ 8. Then the /dev/rtc
13 * interface can be used to make use of these timer interrupts,
14 * be they interval or alarm based.
15 *
16 * The /dev/rtc interface will block on reads until an interrupt
17 * has been received. If a RTC interrupt has already happened,
18 * it will output an unsigned long and then block. The output value
19 * contains the interrupt status in the low byte and the number of
20 * interrupts since the last read in the remaining high bytes. The
21 * /dev/rtc interface can also be used with the select(2) call.
22 *
23 * This program is free software; you can redistribute it and/or
24 * modify it under the terms of the GNU General Public License
25 * as published by the Free Software Foundation; either version
26 * 2 of the License, or (at your option) any later version.
27 *
28 * Based on other minimal char device drivers, like Alan's
29 * watchdog, Ted's random, etc. etc.
30 *
31 * 1.07 Paul Gortmaker.
32 * 1.08 Miquel van Smoorenburg: disallow certain things on the
33 * DEC Alpha as the CMOS clock is also used for other things.
34 * 1.09 Nikita Schmidt: epoch support and some Alpha cleanup.
35 * 1.09a Pete Zaitcev: Sun SPARC
36 * 1.09b Jeff Garzik: Modularize, init cleanup
37 * 1.09c Jeff Garzik: SMP cleanup
38 * 1.10 Paul Barton-Davis: add support for async I/O
39 * 1.10a Andrea Arcangeli: Alpha updates
40 * 1.10b Andrew Morton: SMP lock fix
41 * 1.10c Cesar Barros: SMP locking fixes and cleanup
42 * 1.10d Paul Gortmaker: delete paranoia check in rtc_exit
43 * 1.10e Maciej W. Rozycki: Handle DECstation's year weirdness.
44 * 1.11 Takashi Iwai: Kernel access functions
45 * rtc_register/rtc_unregister/rtc_control
46 * 1.11a Daniele Bellucci: Audit create_proc_read_entry in rtc_init
47 * 1.12 Venkatesh Pallipadi: Hooks for emulating rtc on HPET base-timer
48 * CONFIG_HPET_EMULATE_RTC
49 *
50 */
51
52#define RTC_VERSION "1.12"
53
54#define RTC_IO_EXTENT 0x8
55
56/*
57 * Note that *all* calls to CMOS_READ and CMOS_WRITE are done with
58 * interrupts disabled. Due to the index-port/data-port (0x70/0x71)
59 * design of the RTC, we don't want two different things trying to
60 * get to it at once. (e.g. the periodic 11 min sync from time.c vs.
61 * this driver.)
62 */
63
64#include <linux/config.h>
65#include <linux/interrupt.h>
66#include <linux/module.h>
67#include <linux/kernel.h>
68#include <linux/types.h>
69#include <linux/miscdevice.h>
70#include <linux/ioport.h>
71#include <linux/fcntl.h>
72#include <linux/mc146818rtc.h>
73#include <linux/init.h>
74#include <linux/poll.h>
75#include <linux/proc_fs.h>
76#include <linux/seq_file.h>
77#include <linux/spinlock.h>
78#include <linux/sysctl.h>
79#include <linux/wait.h>
80#include <linux/bcd.h>
47f176fd 81#include <linux/delay.h>
1da177e4
LT		 82
83#include <asm/current.h>
84#include <asm/uaccess.h>
85#include <asm/system.h>
86
87#if defined(__i386__)
88#include <asm/hpet.h>
89#endif
90
91#ifdef __sparc__
92#include <linux/pci.h>
93#include <asm/ebus.h>
94#ifdef __sparc_v9__
95#include <asm/isa.h>
96#endif
97
98static unsigned long rtc_port;
99static int rtc_irq = PCI_IRQ_NONE;
100#endif
101
102#ifdef CONFIG_HPET_RTC_IRQ
103#undef RTC_IRQ
104#endif
105
106#ifdef RTC_IRQ
107static int rtc_has_irq = 1;
108#endif
109
110#ifndef CONFIG_HPET_EMULATE_RTC
111#define is_hpet_enabled() 0
112#define hpet_set_alarm_time(hrs, min, sec) 0
113#define hpet_set_periodic_freq(arg) 0
114#define hpet_mask_rtc_irq_bit(arg) 0
115#define hpet_set_rtc_irq_bit(arg) 0
116#define hpet_rtc_timer_init() do { } while (0)
117#define hpet_rtc_dropped_irq() 0
118static inline irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs) {return 0;}
119#else
120extern irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs);
121#endif
122
123/*
124 * We sponge a minor off of the misc major. No need slurping
125 * up another valuable major dev number for this. If you add
126 * an ioctl, make sure you don't conflict with SPARC's RTC
127 * ioctls.
128 */
129
130static struct fasync_struct *rtc_async_queue;
131
132static DECLARE_WAIT_QUEUE_HEAD(rtc_wait);
133
134#ifdef RTC_IRQ
135static struct timer_list rtc_irq_timer;
136#endif
137
138static ssize_t rtc_read(struct file *file, char __user *buf,
139 size_t count, loff_t *ppos);
140
141static int rtc_ioctl(struct inode *inode, struct file *file,
142 unsigned int cmd, unsigned long arg);
143
144#ifdef RTC_IRQ
145static unsigned int rtc_poll(struct file *file, poll_table *wait);
146#endif
147
148static void get_rtc_alm_time (struct rtc_time *alm_tm);
149#ifdef RTC_IRQ
150static void rtc_dropped_irq(unsigned long data);
151
c3348760
TI		 152static void set_rtc_irq_bit_locked(unsigned char bit);
153static void mask_rtc_irq_bit_locked(unsigned char bit);
154
155static inline void set_rtc_irq_bit(unsigned char bit)
156{
157 spin_lock_irq(&rtc_lock);
158 set_rtc_irq_bit_locked(bit);
159 spin_unlock_irq(&rtc_lock);
160}
161
162static void mask_rtc_irq_bit(unsigned char bit)
163{
164 spin_lock_irq(&rtc_lock);
165 mask_rtc_irq_bit_locked(bit);
166 spin_unlock_irq(&rtc_lock);
167}
1da177e4
LT		 168#endif
169
170static int rtc_proc_open(struct inode *inode, struct file *file);
171
172/*
173 * Bits in rtc_status. (6 bits of room for future expansion)
174 */
175
176#define RTC_IS_OPEN 0x01 /* means /dev/rtc is in use */
177#define RTC_TIMER_ON 0x02 /* missed irq timer active */
178
179/*
180 * rtc_status is never changed by rtc_interrupt, and ioctl/open/close is
181 * protected by the big kernel lock. However, ioctl can still disable the timer
182 * in rtc_status and then with del_timer after the interrupt has read
183 * rtc_status but before mod_timer is called, which would then reenable the
184 * timer (but you would need to have an awful timing before you'd trip on it)
185 */
186static unsigned long rtc_status = 0; /* bitmapped status byte. */
187static unsigned long rtc_freq = 0; /* Current periodic IRQ rate */
188static unsigned long rtc_irq_data = 0; /* our output to the world */
189static unsigned long rtc_max_user_freq = 64; /* > this, need CAP_SYS_RESOURCE */
190
191#ifdef RTC_IRQ
192/*
193 * rtc_task_lock nests inside rtc_lock.
194 */
195static DEFINE_SPINLOCK(rtc_task_lock);
196static rtc_task_t *rtc_callback = NULL;
197#endif
198
199/*
200 * If this driver ever becomes modularised, it will be really nice
201 * to make the epoch retain its value across module reload...
202 */
203
204static unsigned long epoch = 1900; /* year corresponding to 0x00 */
205
206static const unsigned char days_in_mo[] =
207{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
208
209/*
210 * Returns true if a clock update is in progress
211 */
212static inline unsigned char rtc_is_updating(void)
213{
214 unsigned char uip;
215
216 spin_lock_irq(&rtc_lock);
217 uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP);
218 spin_unlock_irq(&rtc_lock);
219 return uip;
220}
221
222#ifdef RTC_IRQ
223/*
224 * A very tiny interrupt handler. It runs with SA_INTERRUPT set,
225 * but there is possibility of conflicting with the set_rtc_mmss()
226 * call (the rtc irq and the timer irq can easily run at the same
227 * time in two different CPUs). So we need to serialize
228 * accesses to the chip with the rtc_lock spinlock that each
229 * architecture should implement in the timer code.
230 * (See ./arch/XXXX/kernel/time.c for the set_rtc_mmss() function.)
231 */
232
233irqreturn_t rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
234{
235 /*
236 * Can be an alarm interrupt, update complete interrupt,
237 * or a periodic interrupt. We store the status in the
238 * low byte and the number of interrupts received since
239 * the last read in the remainder of rtc_irq_data.
240 */
241
242 spin_lock (&rtc_lock);
243 rtc_irq_data += 0x100;
244 rtc_irq_data &= ~0xff;
245 if (is_hpet_enabled()) {
246 /*
247 * In this case it is HPET RTC interrupt handler
248 * calling us, with the interrupt information
249 * passed as arg1, instead of irq.
250 */
251 rtc_irq_data |= (unsigned long)irq & 0xF0;
252 } else {
253 rtc_irq_data |= (CMOS_READ(RTC_INTR_FLAGS) & 0xF0);
254 }
255
256 if (rtc_status & RTC_TIMER_ON)
257 mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100);
258
259 spin_unlock (&rtc_lock);
260
261 /* Now do the rest of the actions */
262 spin_lock(&rtc_task_lock);
263 if (rtc_callback)
264 rtc_callback->func(rtc_callback->private_data);
265 spin_unlock(&rtc_task_lock);
266 wake_up_interruptible(&rtc_wait);
267
268 kill_fasync (&rtc_async_queue, SIGIO, POLL_IN);
269
270 return IRQ_HANDLED;
271}
272#endif
273
274/*
275 * sysctl-tuning infrastructure.
276 */
277static ctl_table rtc_table[] = {
278 {
279 .ctl_name = 1,
280 .procname = "max-user-freq",
281 .data = &rtc_max_user_freq,
282 .maxlen = sizeof(int),
283 .mode = 0644,
284 .proc_handler = &proc_dointvec,
285 },
286 { .ctl_name = 0 }
287};
288
289static ctl_table rtc_root[] = {
290 {
291 .ctl_name = 1,
292 .procname = "rtc",
293 .maxlen = 0,
294 .mode = 0555,
295 .child = rtc_table,
296 },
297 { .ctl_name = 0 }
298};
299
300static ctl_table dev_root[] = {
301 {
302 .ctl_name = CTL_DEV,
303 .procname = "dev",
304 .maxlen = 0,
305 .mode = 0555,
306 .child = rtc_root,
307 },
308 { .ctl_name = 0 }
309};
310
311static struct ctl_table_header *sysctl_header;
312
313static int __init init_sysctl(void)
314{
315 sysctl_header = register_sysctl_table(dev_root, 0);
316 return 0;
317}
318
319static void __exit cleanup_sysctl(void)
320{
321 unregister_sysctl_table(sysctl_header);
322}
323
324/*
325 * Now all the various file operations that we export.
326 */
327
328static ssize_t rtc_read(struct file *file, char __user *buf,
329 size_t count, loff_t *ppos)
330{
331#ifndef RTC_IRQ
332 return -EIO;
333#else
334 DECLARE_WAITQUEUE(wait, current);
335 unsigned long data;
336 ssize_t retval;
337
338 if (rtc_has_irq == 0)
339 return -EIO;
340
341 if (count < sizeof(unsigned))
342 return -EINVAL;
343
344 add_wait_queue(&rtc_wait, &wait);
345
346 do {
347 /* First make it right. Then make it fast. Putting this whole
348 * block within the parentheses of a while would be too
349 * confusing. And no, xchg() is not the answer. */
350
351 __set_current_state(TASK_INTERRUPTIBLE);
352
353 spin_lock_irq (&rtc_lock);
354 data = rtc_irq_data;
355 rtc_irq_data = 0;
356 spin_unlock_irq (&rtc_lock);
357
358 if (data != 0)
359 break;
360
361 if (file->f_flags & O_NONBLOCK) {
362 retval = -EAGAIN;
363 goto out;
364 }
365 if (signal_pending(current)) {
366 retval = -ERESTARTSYS;
367 goto out;
368 }
369 schedule();
370 } while (1);
371
372 if (count < sizeof(unsigned long))
373 retval = put_user(data, (unsigned int __user *)buf) ?: sizeof(int);
374 else
375 retval = put_user(data, (unsigned long __user *)buf) ?: sizeof(long);
376 out:
377 current->state = TASK_RUNNING;
378 remove_wait_queue(&rtc_wait, &wait);
379
380 return retval;
381#endif
382}
383
384static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, int kernel)
385{
386 struct rtc_time wtime;
387
388#ifdef RTC_IRQ
389 if (rtc_has_irq == 0) {
390 switch (cmd) {
391 case RTC_AIE_OFF:
392 case RTC_AIE_ON:
393 case RTC_PIE_OFF:
394 case RTC_PIE_ON:
395 case RTC_UIE_OFF:
396 case RTC_UIE_ON:
397 case RTC_IRQP_READ:
398 case RTC_IRQP_SET:
399 return -EINVAL;
400 };
401 }
402#endif
403
404 switch (cmd) {
405#ifdef RTC_IRQ
406 case RTC_AIE_OFF: /* Mask alarm int. enab. bit */
407 {
408 mask_rtc_irq_bit(RTC_AIE);
409 return 0;
410 }
411 case RTC_AIE_ON: /* Allow alarm interrupts. */
412 {
413 set_rtc_irq_bit(RTC_AIE);
414 return 0;
415 }
416 case RTC_PIE_OFF: /* Mask periodic int. enab. bit */
417 {
c3348760
TI		 418 unsigned long flags; /* can be called from isr via rtc_control() */
419 spin_lock_irqsave (&rtc_lock, flags);
420 mask_rtc_irq_bit_locked(RTC_PIE);
1da177e4 421 if (rtc_status & RTC_TIMER_ON) {
1da177e4
LT		 422 rtc_status &= ~RTC_TIMER_ON;
423 del_timer(&rtc_irq_timer);
1da177e4 424 }
c3348760 425 spin_unlock_irqrestore (&rtc_lock, flags);
1da177e4
LT		 426 return 0;
427 }
428 case RTC_PIE_ON: /* Allow periodic ints */
429 {
c3348760 430 unsigned long flags; /* can be called from isr via rtc_control() */
1da177e4
LT		 431 /*
432 * We don't really want Joe User enabling more
433 * than 64Hz of interrupts on a multi-user machine.
434 */
435 if (!kernel && (rtc_freq > rtc_max_user_freq) &&
436 (!capable(CAP_SYS_RESOURCE)))
437 return -EACCES;
438
c3348760 439 spin_lock_irqsave (&rtc_lock, flags);
1da177e4 440 if (!(rtc_status & RTC_TIMER_ON)) {
1da177e4
LT		 441 rtc_irq_timer.expires = jiffies + HZ/rtc_freq + 2*HZ/100;
442 add_timer(&rtc_irq_timer);
443 rtc_status |= RTC_TIMER_ON;
1da177e4 444 }
c3348760
TI		 445 set_rtc_irq_bit_locked(RTC_PIE);
446 spin_unlock_irqrestore (&rtc_lock, flags);
1da177e4
LT		 447 return 0;
448 }
449 case RTC_UIE_OFF: /* Mask ints from RTC updates. */
450 {
451 mask_rtc_irq_bit(RTC_UIE);
452 return 0;
453 }
454 case RTC_UIE_ON: /* Allow ints for RTC updates. */
455 {
456 set_rtc_irq_bit(RTC_UIE);
457 return 0;
458 }
459#endif
460 case RTC_ALM_READ: /* Read the present alarm time */
461 {
462 /*
463 * This returns a struct rtc_time. Reading >= 0xc0
464 * means "don't care" or "match all". Only the tm_hour,
465 * tm_min, and tm_sec values are filled in.
466 */
467 memset(&wtime, 0, sizeof(struct rtc_time));
468 get_rtc_alm_time(&wtime);
469 break;
470 }
471 case RTC_ALM_SET: /* Store a time into the alarm */
472 {
473 /*
474 * This expects a struct rtc_time. Writing 0xff means
475 * "don't care" or "match all". Only the tm_hour,
476 * tm_min and tm_sec are used.
477 */
478 unsigned char hrs, min, sec;
479 struct rtc_time alm_tm;
480
481 if (copy_from_user(&alm_tm, (struct rtc_time __user *)arg,
482 sizeof(struct rtc_time)))
483 return -EFAULT;
484
485 hrs = alm_tm.tm_hour;
486 min = alm_tm.tm_min;
487 sec = alm_tm.tm_sec;
488
489 spin_lock_irq(&rtc_lock);
490 if (hpet_set_alarm_time(hrs, min, sec)) {
491 /*
492 * Fallthru and set alarm time in CMOS too,
493 * so that we will get proper value in RTC_ALM_READ
494 */
495 }
496 if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) ||
497 RTC_ALWAYS_BCD)
498 {
499 if (sec < 60) BIN_TO_BCD(sec);
500 else sec = 0xff;
501
502 if (min < 60) BIN_TO_BCD(min);
503 else min = 0xff;
504
505 if (hrs < 24) BIN_TO_BCD(hrs);
506 else hrs = 0xff;
507 }
508 CMOS_WRITE(hrs, RTC_HOURS_ALARM);
509 CMOS_WRITE(min, RTC_MINUTES_ALARM);
510 CMOS_WRITE(sec, RTC_SECONDS_ALARM);
511 spin_unlock_irq(&rtc_lock);
512
513 return 0;
514 }
515 case RTC_RD_TIME: /* Read the time/date from RTC */
516 {
517 memset(&wtime, 0, sizeof(struct rtc_time));
518 rtc_get_rtc_time(&wtime);
519 break;
520 }
521 case RTC_SET_TIME: /* Set the RTC */
522 {
523 struct rtc_time rtc_tm;
524 unsigned char mon, day, hrs, min, sec, leap_yr;
525 unsigned char save_control, save_freq_select;
526 unsigned int yrs;
527#ifdef CONFIG_MACH_DECSTATION
528 unsigned int real_yrs;
529#endif
530
531 if (!capable(CAP_SYS_TIME))
532 return -EACCES;
533
534 if (copy_from_user(&rtc_tm, (struct rtc_time __user *)arg,
535 sizeof(struct rtc_time)))
536 return -EFAULT;
537
538 yrs = rtc_tm.tm_year + 1900;
539 mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */
540 day = rtc_tm.tm_mday;
541 hrs = rtc_tm.tm_hour;
542 min = rtc_tm.tm_min;
543 sec = rtc_tm.tm_sec;
544
545 if (yrs < 1970)
546 return -EINVAL;
547
548 leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
549
550 if ((mon > 12) || (day == 0))
551 return -EINVAL;
552
553 if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
554 return -EINVAL;
555
556 if ((hrs >= 24) || (min >= 60) || (sec >= 60))
557 return -EINVAL;
558
559 if ((yrs -= epoch) > 255) /* They are unsigned */
560 return -EINVAL;
561
562 spin_lock_irq(&rtc_lock);
563#ifdef CONFIG_MACH_DECSTATION
564 real_yrs = yrs;
565 yrs = 72;
566
567 /*
568 * We want to keep the year set to 73 until March
569 * for non-leap years, so that Feb, 29th is handled
570 * correctly.
571 */
572 if (!leap_yr && mon < 3) {
573 real_yrs--;
574 yrs = 73;
575 }
576#endif
577 /* These limits and adjustments are independent of
578 * whether the chip is in binary mode or not.
579 */
580 if (yrs > 169) {
581 spin_unlock_irq(&rtc_lock);
582 return -EINVAL;
583 }
584 if (yrs >= 100)
585 yrs -= 100;
586
587 if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY)
588 || RTC_ALWAYS_BCD) {
589 BIN_TO_BCD(sec);
590 BIN_TO_BCD(min);
591 BIN_TO_BCD(hrs);
592 BIN_TO_BCD(day);
593 BIN_TO_BCD(mon);
594 BIN_TO_BCD(yrs);
595 }
596
597 save_control = CMOS_READ(RTC_CONTROL);
598 CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL);
599 save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
600 CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);
601
602#ifdef CONFIG_MACH_DECSTATION
603 CMOS_WRITE(real_yrs, RTC_DEC_YEAR);
604#endif
605 CMOS_WRITE(yrs, RTC_YEAR);
606 CMOS_WRITE(mon, RTC_MONTH);
607 CMOS_WRITE(day, RTC_DAY_OF_MONTH);
608 CMOS_WRITE(hrs, RTC_HOURS);
609 CMOS_WRITE(min, RTC_MINUTES);
610 CMOS_WRITE(sec, RTC_SECONDS);
611
612 CMOS_WRITE(save_control, RTC_CONTROL);
613 CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
614
615 spin_unlock_irq(&rtc_lock);
616 return 0;
617 }
618#ifdef RTC_IRQ
619 case RTC_IRQP_READ: /* Read the periodic IRQ rate. */
620 {
621 return put_user(rtc_freq, (unsigned long __user *)arg);
622 }
623 case RTC_IRQP_SET: /* Set periodic IRQ rate. */
624 {
625 int tmp = 0;
626 unsigned char val;
c3348760 627 unsigned long flags; /* can be called from isr via rtc_control() */
1da177e4
LT		 628
629 /*
630 * The max we can do is 8192Hz.
631 */
632 if ((arg < 2) || (arg > 8192))
633 return -EINVAL;
634 /*
635 * We don't really want Joe User generating more
636 * than 64Hz of interrupts on a multi-user machine.
637 */
638 if (!kernel && (arg > rtc_max_user_freq) && (!capable(CAP_SYS_RESOURCE)))
639 return -EACCES;
640
641 while (arg > (1<<tmp))
642 tmp++;
643
644 /*
645 * Check that the input was really a power of 2.
646 */
647 if (arg != (1<<tmp))
648 return -EINVAL;
649
c3348760 650 spin_lock_irqsave(&rtc_lock, flags);
1da177e4 651 if (hpet_set_periodic_freq(arg)) {
c3348760 652 spin_unlock_irqrestore(&rtc_lock, flags);
1da177e4
LT		 653 return 0;
654 }
655 rtc_freq = arg;
656
657 val = CMOS_READ(RTC_FREQ_SELECT) & 0xf0;
658 val |= (16 - tmp);
659 CMOS_WRITE(val, RTC_FREQ_SELECT);
c3348760 660 spin_unlock_irqrestore(&rtc_lock, flags);
1da177e4
LT		 661 return 0;
662 }
663#endif
664 case RTC_EPOCH_READ: /* Read the epoch. */
665 {
666 return put_user (epoch, (unsigned long __user *)arg);
667 }
668 case RTC_EPOCH_SET: /* Set the epoch. */
669 {
670 /*
671 * There were no RTC clocks before 1900.
672 */
673 if (arg < 1900)
674 return -EINVAL;
675
676 if (!capable(CAP_SYS_TIME))
677 return -EACCES;
678
679 epoch = arg;
680 return 0;
681 }
682 default:
683 return -ENOTTY;
684 }
685 return copy_to_user((void __user *)arg, &wtime, sizeof wtime) ? -EFAULT : 0;
686}
687
688static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
689 unsigned long arg)
690{
691 return rtc_do_ioctl(cmd, arg, 0);
692}
693
694/*
695 * We enforce only one user at a time here with the open/close.
696 * Also clear the previous interrupt data on an open, and clean
697 * up things on a close.
698 */
699
700/* We use rtc_lock to protect against concurrent opens. So the BKL is not
701 * needed here. Or anywhere else in this driver. */
702static int rtc_open(struct inode *inode, struct file *file)
703{
704 spin_lock_irq (&rtc_lock);
705
706 if(rtc_status & RTC_IS_OPEN)
707 goto out_busy;
708
709 rtc_status |= RTC_IS_OPEN;
710
711 rtc_irq_data = 0;
712 spin_unlock_irq (&rtc_lock);
713 return 0;
714
715out_busy:
716 spin_unlock_irq (&rtc_lock);
717 return -EBUSY;
718}
719
720static int rtc_fasync (int fd, struct file *filp, int on)
721
722{
723 return fasync_helper (fd, filp, on, &rtc_async_queue);
724}
725
726static int rtc_release(struct inode *inode, struct file *file)
727{
728#ifdef RTC_IRQ
729 unsigned char tmp;
730
731 if (rtc_has_irq == 0)
732 goto no_irq;
733
734 /*
735 * Turn off all interrupts once the device is no longer
736 * in use, and clear the data.
737 */
738
739 spin_lock_irq(&rtc_lock);
740 if (!hpet_mask_rtc_irq_bit(RTC_PIE | RTC_AIE | RTC_UIE)) {
741 tmp = CMOS_READ(RTC_CONTROL);
742 tmp &= ~RTC_PIE;
743 tmp &= ~RTC_AIE;
744 tmp &= ~RTC_UIE;
745 CMOS_WRITE(tmp, RTC_CONTROL);
746 CMOS_READ(RTC_INTR_FLAGS);
747 }
748 if (rtc_status & RTC_TIMER_ON) {
749 rtc_status &= ~RTC_TIMER_ON;
750 del_timer(&rtc_irq_timer);
751 }
752 spin_unlock_irq(&rtc_lock);
753
754 if (file->f_flags & FASYNC) {
755 rtc_fasync (-1, file, 0);
756 }
757no_irq:
758#endif
759
760 spin_lock_irq (&rtc_lock);
761 rtc_irq_data = 0;
762 rtc_status &= ~RTC_IS_OPEN;
763 spin_unlock_irq (&rtc_lock);
764 return 0;
765}
766
767#ifdef RTC_IRQ
768/* Called without the kernel lock - fine */
769static unsigned int rtc_poll(struct file *file, poll_table *wait)
770{
771 unsigned long l;
772
773 if (rtc_has_irq == 0)
774 return 0;
775
776 poll_wait(file, &rtc_wait, wait);
777
778 spin_lock_irq (&rtc_lock);
779 l = rtc_irq_data;
780 spin_unlock_irq (&rtc_lock);
781
782 if (l != 0)
783 return POLLIN | POLLRDNORM;
784 return 0;
785}
786#endif
787
788/*
789 * exported stuffs
790 */
791
792EXPORT_SYMBOL(rtc_register);
793EXPORT_SYMBOL(rtc_unregister);
794EXPORT_SYMBOL(rtc_control);
795
796int rtc_register(rtc_task_t *task)
797{
798#ifndef RTC_IRQ
799 return -EIO;
800#else
801 if (task == NULL || task->func == NULL)
802 return -EINVAL;
803 spin_lock_irq(&rtc_lock);
804 if (rtc_status & RTC_IS_OPEN) {
805 spin_unlock_irq(&rtc_lock);
806 return -EBUSY;
807 }
808 spin_lock(&rtc_task_lock);
809 if (rtc_callback) {
810 spin_unlock(&rtc_task_lock);
811 spin_unlock_irq(&rtc_lock);
812 return -EBUSY;
813 }
814 rtc_status |= RTC_IS_OPEN;
815 rtc_callback = task;
816 spin_unlock(&rtc_task_lock);
817 spin_unlock_irq(&rtc_lock);
818 return 0;
819#endif
820}
821
822int rtc_unregister(rtc_task_t *task)
823{
824#ifndef RTC_IRQ
825 return -EIO;
826#else
827 unsigned char tmp;
828
829 spin_lock_irq(&rtc_lock);
830 spin_lock(&rtc_task_lock);
831 if (rtc_callback != task) {
832 spin_unlock(&rtc_task_lock);
833 spin_unlock_irq(&rtc_lock);
834 return -ENXIO;
835 }
836 rtc_callback = NULL;
837
838 /* disable controls */
839 if (!hpet_mask_rtc_irq_bit(RTC_PIE | RTC_AIE | RTC_UIE)) {
840 tmp = CMOS_READ(RTC_CONTROL);
841 tmp &= ~RTC_PIE;
842 tmp &= ~RTC_AIE;
843 tmp &= ~RTC_UIE;
844 CMOS_WRITE(tmp, RTC_CONTROL);
845 CMOS_READ(RTC_INTR_FLAGS);
846 }
847 if (rtc_status & RTC_TIMER_ON) {
848 rtc_status &= ~RTC_TIMER_ON;
849 del_timer(&rtc_irq_timer);
850 }
851 rtc_status &= ~RTC_IS_OPEN;
852 spin_unlock(&rtc_task_lock);
853 spin_unlock_irq(&rtc_lock);
854 return 0;
855#endif
856}
857
858int rtc_control(rtc_task_t *task, unsigned int cmd, unsigned long arg)
859{
860#ifndef RTC_IRQ
861 return -EIO;
862#else
c3348760
TI		 863 unsigned long flags;
864 if (cmd != RTC_PIE_ON && cmd != RTC_PIE_OFF && cmd != RTC_IRQP_SET)
865 return -EINVAL;
866 spin_lock_irqsave(&rtc_task_lock, flags);
1da177e4 867 if (rtc_callback != task) {
c3348760 868 spin_unlock_irqrestore(&rtc_task_lock, flags);
1da177e4
LT		 869 return -ENXIO;
870 }
c3348760 871 spin_unlock_irqrestore(&rtc_task_lock, flags);
1da177e4
LT		 872 return rtc_do_ioctl(cmd, arg, 1);
873#endif
874}
875
876
877/*
878 * The various file operations we support.
879 */
880
881static struct file_operations rtc_fops = {
882 .owner = THIS_MODULE,
883 .llseek = no_llseek,
884 .read = rtc_read,
885#ifdef RTC_IRQ
886 .poll = rtc_poll,
887#endif
888 .ioctl = rtc_ioctl,
889 .open = rtc_open,
890 .release = rtc_release,
891 .fasync = rtc_fasync,
892};
893
894static struct miscdevice rtc_dev = {
895 .minor = RTC_MINOR,
896 .name = "rtc",
897 .fops = &rtc_fops,
898};
899
900static struct file_operations rtc_proc_fops = {
901 .owner = THIS_MODULE,
902 .open = rtc_proc_open,
903 .read = seq_read,
904 .llseek = seq_lseek,
905 .release = single_release,
906};
907
908#if defined(RTC_IRQ) && !defined(__sparc__)
909static irqreturn_t (*rtc_int_handler_ptr)(int irq, void *dev_id, struct pt_regs *regs);
910#endif
911
912static int __init rtc_init(void)
913{
914 struct proc_dir_entry *ent;
915#if defined(__alpha__) || defined(__mips__)
916 unsigned int year, ctrl;
1da177e4
LT		 917 char *guess = NULL;
918#endif
919#ifdef __sparc__
920 struct linux_ebus *ebus;
921 struct linux_ebus_device *edev;
922#ifdef __sparc_v9__
923 struct sparc_isa_bridge *isa_br;
924 struct sparc_isa_device *isa_dev;
925#endif
926#endif
927
928#ifdef __sparc__
929 for_each_ebus(ebus) {
930 for_each_ebusdev(edev, ebus) {
931 if(strcmp(edev->prom_name, "rtc") == 0) {
932 rtc_port = edev->resource[0].start;
933 rtc_irq = edev->irqs[0];
934 goto found;
935 }
936 }
937 }
938#ifdef __sparc_v9__
939 for_each_isa(isa_br) {
940 for_each_isadev(isa_dev, isa_br) {
941 if (strcmp(isa_dev->prom_name, "rtc") == 0) {
942 rtc_port = isa_dev->resource.start;
943 rtc_irq = isa_dev->irq;
944 goto found;
945 }
946 }
947 }
948#endif
949 printk(KERN_ERR "rtc_init: no PC rtc found\n");
950 return -EIO;
951
952found:
953 if (rtc_irq == PCI_IRQ_NONE) {
954 rtc_has_irq = 0;
955 goto no_irq;
956 }
957
958 /*
959 * XXX Interrupt pin #7 in Espresso is shared between RTC and
53d0fc27 960 * PCI Slot 2 INTA# (and some INTx# in Slot 1).
1da177e4 961 */
53d0fc27 962 if (request_irq(rtc_irq, rtc_interrupt, SA_SHIRQ, "rtc", (void *)&rtc_port)) {
1da177e4
LT		 963 /*
964 * Standard way for sparc to print irq's is to use
965 * __irq_itoa(). I think for EBus it's ok to use %d.
966 */
967 printk(KERN_ERR "rtc: cannot register IRQ %d\n", rtc_irq);
968 return -EIO;
969 }
970no_irq:
971#else
972 if (!request_region(RTC_PORT(0), RTC_IO_EXTENT, "rtc")) {
973 printk(KERN_ERR "rtc: I/O port %d is not free.\n", RTC_PORT (0));
974 return -EIO;
975 }
976
977#ifdef RTC_IRQ
978 if (is_hpet_enabled()) {
979 rtc_int_handler_ptr = hpet_rtc_interrupt;
980 } else {
981 rtc_int_handler_ptr = rtc_interrupt;
982 }
983
984 if(request_irq(RTC_IRQ, rtc_int_handler_ptr, SA_INTERRUPT, "rtc", NULL)) {
985 /* Yeah right, seeing as irq 8 doesn't even hit the bus. */
986 printk(KERN_ERR "rtc: IRQ %d is not free.\n", RTC_IRQ);
987 release_region(RTC_PORT(0), RTC_IO_EXTENT);
988 return -EIO;
989 }
990 hpet_rtc_timer_init();
991
992#endif
993
994#endif /* __sparc__ vs. others */
995
996 if (misc_register(&rtc_dev)) {
997#ifdef RTC_IRQ
998 free_irq(RTC_IRQ, NULL);
999#endif
1000 release_region(RTC_PORT(0), RTC_IO_EXTENT);
1001 return -ENODEV;
1002 }
1003
1004 ent = create_proc_entry("driver/rtc", 0, NULL);
1005 if (!ent) {
1006#ifdef RTC_IRQ
1007 free_irq(RTC_IRQ, NULL);
1008#endif
1009 release_region(RTC_PORT(0), RTC_IO_EXTENT);
1010 misc_deregister(&rtc_dev);
1011 return -ENOMEM;
1012 }
1013 ent->proc_fops = &rtc_proc_fops;
1014
1015#if defined(__alpha__) || defined(__mips__)
1016 rtc_freq = HZ;
1017
1018 /* Each operating system on an Alpha uses its own epoch.
1019 Let's try to guess which one we are using now. */
1020
1da177e4 1021 if (rtc_is_updating() != 0)
47f176fd 1022 msleep(20);
1da177e4
LT		 1023
1024 spin_lock_irq(&rtc_lock);
1025 year = CMOS_READ(RTC_YEAR);
1026 ctrl = CMOS_READ(RTC_CONTROL);
1027 spin_unlock_irq(&rtc_lock);
1028
1029 if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
1030 BCD_TO_BIN(year); /* This should never happen... */
1031
1032 if (year < 20) {
1033 epoch = 2000;
1034 guess = "SRM (post-2000)";
1035 } else if (year >= 20 && year < 48) {
1036 epoch = 1980;
1037 guess = "ARC console";
1038 } else if (year >= 48 && year < 72) {
1039 epoch = 1952;
1040 guess = "Digital UNIX";
1041#if defined(__mips__)
1042 } else if (year >= 72 && year < 74) {
1043 epoch = 2000;
1044 guess = "Digital DECstation";
1045#else
1046 } else if (year >= 70) {
1047 epoch = 1900;
1048 guess = "Standard PC (1900)";
1049#endif
1050 }
1051 if (guess)
1052 printk(KERN_INFO "rtc: %s epoch (%lu) detected\n", guess, epoch);
1053#endif
1054#ifdef RTC_IRQ
1055 if (rtc_has_irq == 0)
1056 goto no_irq2;
1057
1058 init_timer(&rtc_irq_timer);
1059 rtc_irq_timer.function = rtc_dropped_irq;
1060 spin_lock_irq(&rtc_lock);
1061 rtc_freq = 1024;
1062 if (!hpet_set_periodic_freq(rtc_freq)) {
1063 /* Initialize periodic freq. to CMOS reset default, which is 1024Hz */
1064 CMOS_WRITE(((CMOS_READ(RTC_FREQ_SELECT) & 0xF0) | 0x06), RTC_FREQ_SELECT);
1065 }
1066 spin_unlock_irq(&rtc_lock);
1067no_irq2:
1068#endif
1069
1070 (void) init_sysctl();
1071
1072 printk(KERN_INFO "Real Time Clock Driver v" RTC_VERSION "\n");
1073
1074 return 0;
1075}
1076
1077static void __exit rtc_exit (void)
1078{
1079 cleanup_sysctl();
1080 remove_proc_entry ("driver/rtc", NULL);
1081 misc_deregister(&rtc_dev);
1082
1083#ifdef __sparc__
1084 if (rtc_has_irq)
1085 free_irq (rtc_irq, &rtc_port);
1086#else
1087 release_region (RTC_PORT (0), RTC_IO_EXTENT);
1088#ifdef RTC_IRQ
1089 if (rtc_has_irq)
1090 free_irq (RTC_IRQ, NULL);
1091#endif
1092#endif /* __sparc__ */
1093}
1094
1095module_init(rtc_init);
1096module_exit(rtc_exit);
1097
1098#ifdef RTC_IRQ
1099/*
1100 * At IRQ rates >= 4096Hz, an interrupt may get lost altogether.
1101 * (usually during an IDE disk interrupt, with IRQ unmasking off)
1102 * Since the interrupt handler doesn't get called, the IRQ status
1103 * byte doesn't get read, and the RTC stops generating interrupts.
1104 * A timer is set, and will call this function if/when that happens.
1105 * To get it out of this stalled state, we just read the status.
1106 * At least a jiffy of interrupts (rtc_freq/HZ) will have been lost.
1107 * (You *really* shouldn't be trying to use a non-realtime system
1108 * for something that requires a steady > 1KHz signal anyways.)
1109 */
1110
1111static void rtc_dropped_irq(unsigned long data)
1112{
1113 unsigned long freq;
1114
1115 spin_lock_irq (&rtc_lock);
1116
1117 if (hpet_rtc_dropped_irq()) {
1118 spin_unlock_irq(&rtc_lock);
1119 return;
1120 }
1121
1122 /* Just in case someone disabled the timer from behind our back... */
1123 if (rtc_status & RTC_TIMER_ON)
1124 mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100);
1125
1126 rtc_irq_data += ((rtc_freq/HZ)<<8);
1127 rtc_irq_data &= ~0xff;
1128 rtc_irq_data |= (CMOS_READ(RTC_INTR_FLAGS) & 0xF0); /* restart */
1129
1130 freq = rtc_freq;
1131
1132 spin_unlock_irq(&rtc_lock);
1133
1134 printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n", freq);
1135
1136 /* Now we have new data */
1137 wake_up_interruptible(&rtc_wait);
1138
1139 kill_fasync (&rtc_async_queue, SIGIO, POLL_IN);
1140}
1141#endif
1142
1143/*
1144 * Info exported via "/proc/driver/rtc".
1145 */
1146
1147static int rtc_proc_show(struct seq_file *seq, void *v)
1148{
1149#define YN(bit) ((ctrl & bit) ? "yes" : "no")
1150#define NY(bit) ((ctrl & bit) ? "no" : "yes")
1151 struct rtc_time tm;
1152 unsigned char batt, ctrl;
1153 unsigned long freq;
1154
1155 spin_lock_irq(&rtc_lock);
1156 batt = CMOS_READ(RTC_VALID) & RTC_VRT;
1157 ctrl = CMOS_READ(RTC_CONTROL);
1158 freq = rtc_freq;
1159 spin_unlock_irq(&rtc_lock);
1160
1161
1162 rtc_get_rtc_time(&tm);
1163
1164 /*
1165 * There is no way to tell if the luser has the RTC set for local
1166 * time or for Universal Standard Time (GMT). Probably local though.
1167 */
1168 seq_printf(seq,
1169 "rtc_time\t: %02d:%02d:%02d\n"
1170 "rtc_date\t: %04d-%02d-%02d\n"
1171 "rtc_epoch\t: %04lu\n",
1172 tm.tm_hour, tm.tm_min, tm.tm_sec,
1173 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, epoch);
1174
1175 get_rtc_alm_time(&tm);
1176
1177 /*
1178 * We implicitly assume 24hr mode here. Alarm values >= 0xc0 will
1179 * match any value for that particular field. Values that are
1180 * greater than a valid time, but less than 0xc0 shouldn't appear.
1181 */
1182 seq_puts(seq, "alarm\t\t: ");
1183 if (tm.tm_hour <= 24)
1184 seq_printf(seq, "%02d:", tm.tm_hour);
1185 else
1186 seq_puts(seq, "**:");
1187
1188 if (tm.tm_min <= 59)
1189 seq_printf(seq, "%02d:", tm.tm_min);
1190 else
1191 seq_puts(seq, "**:");
1192
1193 if (tm.tm_sec <= 59)
1194 seq_printf(seq, "%02d\n", tm.tm_sec);
1195 else
1196 seq_puts(seq, "**\n");
1197
1198 seq_printf(seq,
1199 "DST_enable\t: %s\n"
1200 "BCD\t\t: %s\n"
1201 "24hr\t\t: %s\n"
1202 "square_wave\t: %s\n"
1203 "alarm_IRQ\t: %s\n"
1204 "update_IRQ\t: %s\n"
1205 "periodic_IRQ\t: %s\n"
1206 "periodic_freq\t: %ld\n"
1207 "batt_status\t: %s\n",
1208 YN(RTC_DST_EN),
1209 NY(RTC_DM_BINARY),
1210 YN(RTC_24H),
1211 YN(RTC_SQWE),
1212 YN(RTC_AIE),
1213 YN(RTC_UIE),
1214 YN(RTC_PIE),
1215 freq,
1216 batt ? "okay" : "dead");
1217
1218 return 0;
1219#undef YN
1220#undef NY
1221}
1222
1223static int rtc_proc_open(struct inode *inode, struct file *file)
1224{
1225 return single_open(file, rtc_proc_show, NULL);
1226}
1227
1228void rtc_get_rtc_time(struct rtc_time *rtc_tm)
1229{
403fe5ae 1230 unsigned long uip_watchdog = jiffies;
1da177e4
LT		 1231 unsigned char ctrl;
1232#ifdef CONFIG_MACH_DECSTATION
1233 unsigned int real_year;
1234#endif
1235
1236 /*
1237 * read RTC once any update in progress is done. The update
47f176fd 1238 * can take just over 2ms. We wait 20ms. There is no need to
1da177e4
LT		 1239 * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP.
1240 * If you need to know *exactly* when a second has started, enable
1241 * periodic update complete interrupts, (via ioctl) and then
1242 * immediately read /dev/rtc which will block until you get the IRQ.
1243 * Once the read clears, read the RTC time (again via ioctl). Easy.
1244 */
1245
403fe5ae
PV		 1246 while (rtc_is_updating() != 0 && jiffies - uip_watchdog < 2*HZ/100) {
1247 barrier();
1248 cpu_relax();
1249 }
1da177e4
LT		 1250
1251 /*
1252 * Only the values that we read from the RTC are set. We leave
1253 * tm_wday, tm_yday and tm_isdst untouched. Even though the
1254 * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated
1255 * by the RTC when initially set to a non-zero value.
1256 */
1257 spin_lock_irq(&rtc_lock);
1258 rtc_tm->tm_sec = CMOS_READ(RTC_SECONDS);
1259 rtc_tm->tm_min = CMOS_READ(RTC_MINUTES);
1260 rtc_tm->tm_hour = CMOS_READ(RTC_HOURS);
1261 rtc_tm->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH);
1262 rtc_tm->tm_mon = CMOS_READ(RTC_MONTH);
1263 rtc_tm->tm_year = CMOS_READ(RTC_YEAR);
1264#ifdef CONFIG_MACH_DECSTATION
1265 real_year = CMOS_READ(RTC_DEC_YEAR);
1266#endif
1267 ctrl = CMOS_READ(RTC_CONTROL);
1268 spin_unlock_irq(&rtc_lock);
1269
1270 if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
1271 {
1272 BCD_TO_BIN(rtc_tm->tm_sec);
1273 BCD_TO_BIN(rtc_tm->tm_min);
1274 BCD_TO_BIN(rtc_tm->tm_hour);
1275 BCD_TO_BIN(rtc_tm->tm_mday);
1276 BCD_TO_BIN(rtc_tm->tm_mon);
1277 BCD_TO_BIN(rtc_tm->tm_year);
1278 }
1279
1280#ifdef CONFIG_MACH_DECSTATION
1281 rtc_tm->tm_year += real_year - 72;
1282#endif
1283
1284 /*
1285 * Account for differences between how the RTC uses the values
1286 * and how they are defined in a struct rtc_time;
1287 */
1288 if ((rtc_tm->tm_year += (epoch - 1900)) <= 69)
1289 rtc_tm->tm_year += 100;
1290
1291 rtc_tm->tm_mon--;
1292}
1293
1294static void get_rtc_alm_time(struct rtc_time *alm_tm)
1295{
1296 unsigned char ctrl;
1297
1298 /*
1299 * Only the values that we read from the RTC are set. That
1300 * means only tm_hour, tm_min, and tm_sec.
1301 */
1302 spin_lock_irq(&rtc_lock);
1303 alm_tm->tm_sec = CMOS_READ(RTC_SECONDS_ALARM);
1304 alm_tm->tm_min = CMOS_READ(RTC_MINUTES_ALARM);
1305 alm_tm->tm_hour = CMOS_READ(RTC_HOURS_ALARM);
1306 ctrl = CMOS_READ(RTC_CONTROL);
1307 spin_unlock_irq(&rtc_lock);
1308
1309 if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
1310 {
1311 BCD_TO_BIN(alm_tm->tm_sec);
1312 BCD_TO_BIN(alm_tm->tm_min);
1313 BCD_TO_BIN(alm_tm->tm_hour);
1314 }
1315}
1316
1317#ifdef RTC_IRQ
1318/*
1319 * Used to disable/enable interrupts for any one of UIE, AIE, PIE.
1320 * Rumour has it that if you frob the interrupt enable/disable
1321 * bits in RTC_CONTROL, you should read RTC_INTR_FLAGS, to
1322 * ensure you actually start getting interrupts. Probably for
1323 * compatibility with older/broken chipset RTC implementations.
1324 * We also clear out any old irq data after an ioctl() that
1325 * meddles with the interrupt enable/disable bits.
1326 */
1327
c3348760 1328static void mask_rtc_irq_bit_locked(unsigned char bit)
1da177e4
LT		 1329{
1330 unsigned char val;
1331
c3348760 1332 if (hpet_mask_rtc_irq_bit(bit))
1da177e4 1333 return;
1da177e4
LT		 1334 val = CMOS_READ(RTC_CONTROL);
1335 val &= ~bit;
1336 CMOS_WRITE(val, RTC_CONTROL);
1337 CMOS_READ(RTC_INTR_FLAGS);
1338
1339 rtc_irq_data = 0;
1da177e4
LT		 1340}
1341
c3348760 1342static void set_rtc_irq_bit_locked(unsigned char bit)
1da177e4
LT		 1343{
1344 unsigned char val;
1345
c3348760 1346 if (hpet_set_rtc_irq_bit(bit))
1da177e4 1347 return;
1da177e4
LT		 1348 val = CMOS_READ(RTC_CONTROL);
1349 val |= bit;
1350 CMOS_WRITE(val, RTC_CONTROL);
1351 CMOS_READ(RTC_INTR_FLAGS);
1352
1353 rtc_irq_data = 0;
1da177e4
LT		 1354}
1355#endif
1356
1357MODULE_AUTHOR("Paul Gortmaker");
1358MODULE_LICENSE("GPL");
1359MODULE_ALIAS_MISCDEV(RTC_MINOR);
kernel source for telekom puls (alcatel/mediatek)