Commit | Line | Data |
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1da177e4 | 1 | /* |
5fd1fe9c | 2 | * Real Time Clock interface for Linux |
1da177e4 LT |
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 | |
5fd1fe9c | 20 | * interrupts since the last read in the remaining high bytes. The |
1da177e4 LT |
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 | |
12a0a703 | 38 | * 1.10 Paul Barton-Davis: add support for async I/O |
1da177e4 LT |
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. | |
12a0a703 | 44 | * 1.11 Takashi Iwai: Kernel access functions |
1da177e4 LT |
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 | |
38e0e8c0 | 49 | * 1.12a Maciej W. Rozycki: Handle memory-mapped chips properly. |
b7599587 | 50 | * 1.12ac Alan Cox: Allow read access to the day of week register |
1da177e4 LT |
51 | */ |
52 | ||
b7599587 | 53 | #define RTC_VERSION "1.12ac" |
1da177e4 | 54 | |
1da177e4 LT |
55 | /* |
56 | * Note that *all* calls to CMOS_READ and CMOS_WRITE are done with | |
57 | * interrupts disabled. Due to the index-port/data-port (0x70/0x71) | |
58 | * design of the RTC, we don't want two different things trying to | |
59 | * get to it at once. (e.g. the periodic 11 min sync from time.c vs. | |
60 | * this driver.) | |
61 | */ | |
62 | ||
1da177e4 LT |
63 | #include <linux/interrupt.h> |
64 | #include <linux/module.h> | |
65 | #include <linux/kernel.h> | |
66 | #include <linux/types.h> | |
67 | #include <linux/miscdevice.h> | |
68 | #include <linux/ioport.h> | |
69 | #include <linux/fcntl.h> | |
70 | #include <linux/mc146818rtc.h> | |
71 | #include <linux/init.h> | |
72 | #include <linux/poll.h> | |
73 | #include <linux/proc_fs.h> | |
74 | #include <linux/seq_file.h> | |
75 | #include <linux/spinlock.h> | |
4333deee | 76 | #include <linux/smp_lock.h> |
1da177e4 LT |
77 | #include <linux/sysctl.h> |
78 | #include <linux/wait.h> | |
79 | #include <linux/bcd.h> | |
47f176fd | 80 | #include <linux/delay.h> |
53f1b143 | 81 | #include <linux/uaccess.h> |
1da177e4 LT |
82 | |
83 | #include <asm/current.h> | |
1da177e4 LT |
84 | #include <asm/system.h> |
85 | ||
55f93afd | 86 | #ifdef CONFIG_X86 |
1da177e4 LT |
87 | #include <asm/hpet.h> |
88 | #endif | |
89 | ||
cdee99d7 | 90 | #ifdef CONFIG_SPARC32 |
1da177e4 | 91 | #include <linux/pci.h> |
dca03a51 | 92 | #include <linux/jiffies.h> |
1da177e4 | 93 | #include <asm/ebus.h> |
1da177e4 LT |
94 | |
95 | static unsigned long rtc_port; | |
96 | static int rtc_irq = PCI_IRQ_NONE; | |
97 | #endif | |
98 | ||
99 | #ifdef CONFIG_HPET_RTC_IRQ | |
100 | #undef RTC_IRQ | |
101 | #endif | |
102 | ||
103 | #ifdef RTC_IRQ | |
104 | static int rtc_has_irq = 1; | |
105 | #endif | |
106 | ||
107 | #ifndef CONFIG_HPET_EMULATE_RTC | |
108 | #define is_hpet_enabled() 0 | |
5fd1fe9c IM |
109 | #define hpet_set_alarm_time(hrs, min, sec) 0 |
110 | #define hpet_set_periodic_freq(arg) 0 | |
111 | #define hpet_mask_rtc_irq_bit(arg) 0 | |
112 | #define hpet_set_rtc_irq_bit(arg) 0 | |
113 | #define hpet_rtc_timer_init() do { } while (0) | |
114 | #define hpet_rtc_dropped_irq() 0 | |
32fa4586 DH |
115 | #define hpet_register_irq_handler(h) ({ 0; }) |
116 | #define hpet_unregister_irq_handler(h) ({ 0; }) | |
533ffc28 AM |
117 | #ifdef RTC_IRQ |
118 | static irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id) | |
119 | { | |
120 | return 0; | |
121 | } | |
122 | #endif | |
1da177e4 LT |
123 | #endif |
124 | ||
125 | /* | |
126 | * We sponge a minor off of the misc major. No need slurping | |
127 | * up another valuable major dev number for this. If you add | |
128 | * an ioctl, make sure you don't conflict with SPARC's RTC | |
129 | * ioctls. | |
130 | */ | |
131 | ||
132 | static struct fasync_struct *rtc_async_queue; | |
133 | ||
134 | static DECLARE_WAIT_QUEUE_HEAD(rtc_wait); | |
135 | ||
136 | #ifdef RTC_IRQ | |
40565f19 JS |
137 | static void rtc_dropped_irq(unsigned long data); |
138 | ||
139 | static DEFINE_TIMER(rtc_irq_timer, rtc_dropped_irq, 0, 0); | |
1da177e4 LT |
140 | #endif |
141 | ||
142 | static ssize_t rtc_read(struct file *file, char __user *buf, | |
143 | size_t count, loff_t *ppos); | |
144 | ||
53f1b143 | 145 | static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg); |
9580d85f | 146 | static void rtc_get_rtc_time(struct rtc_time *rtc_tm); |
1da177e4 LT |
147 | |
148 | #ifdef RTC_IRQ | |
149 | static unsigned int rtc_poll(struct file *file, poll_table *wait); | |
150 | #endif | |
151 | ||
5fd1fe9c | 152 | static void get_rtc_alm_time(struct rtc_time *alm_tm); |
1da177e4 | 153 | #ifdef RTC_IRQ |
c3348760 TI |
154 | static void set_rtc_irq_bit_locked(unsigned char bit); |
155 | static void mask_rtc_irq_bit_locked(unsigned char bit); | |
156 | ||
157 | static inline void set_rtc_irq_bit(unsigned char bit) | |
158 | { | |
159 | spin_lock_irq(&rtc_lock); | |
160 | set_rtc_irq_bit_locked(bit); | |
161 | spin_unlock_irq(&rtc_lock); | |
162 | } | |
163 | ||
164 | static void mask_rtc_irq_bit(unsigned char bit) | |
165 | { | |
166 | spin_lock_irq(&rtc_lock); | |
167 | mask_rtc_irq_bit_locked(bit); | |
168 | spin_unlock_irq(&rtc_lock); | |
169 | } | |
1da177e4 LT |
170 | #endif |
171 | ||
9cef779e | 172 | #ifdef CONFIG_PROC_FS |
1da177e4 | 173 | static int rtc_proc_open(struct inode *inode, struct file *file); |
9cef779e | 174 | #endif |
1da177e4 LT |
175 | |
176 | /* | |
177 | * Bits in rtc_status. (6 bits of room for future expansion) | |
178 | */ | |
179 | ||
180 | #define RTC_IS_OPEN 0x01 /* means /dev/rtc is in use */ | |
181 | #define RTC_TIMER_ON 0x02 /* missed irq timer active */ | |
182 | ||
183 | /* | |
184 | * rtc_status is never changed by rtc_interrupt, and ioctl/open/close is | |
185 | * protected by the big kernel lock. However, ioctl can still disable the timer | |
186 | * in rtc_status and then with del_timer after the interrupt has read | |
187 | * rtc_status but before mod_timer is called, which would then reenable the | |
188 | * timer (but you would need to have an awful timing before you'd trip on it) | |
189 | */ | |
5fd1fe9c IM |
190 | static unsigned long rtc_status; /* bitmapped status byte. */ |
191 | static unsigned long rtc_freq; /* Current periodic IRQ rate */ | |
192 | static unsigned long rtc_irq_data; /* our output to the world */ | |
1da177e4 LT |
193 | static unsigned long rtc_max_user_freq = 64; /* > this, need CAP_SYS_RESOURCE */ |
194 | ||
195 | #ifdef RTC_IRQ | |
196 | /* | |
197 | * rtc_task_lock nests inside rtc_lock. | |
198 | */ | |
199 | static DEFINE_SPINLOCK(rtc_task_lock); | |
5fd1fe9c | 200 | static rtc_task_t *rtc_callback; |
1da177e4 LT |
201 | #endif |
202 | ||
203 | /* | |
204 | * If this driver ever becomes modularised, it will be really nice | |
205 | * to make the epoch retain its value across module reload... | |
206 | */ | |
207 | ||
208 | static unsigned long epoch = 1900; /* year corresponding to 0x00 */ | |
209 | ||
5fd1fe9c | 210 | static const unsigned char days_in_mo[] = |
1da177e4 LT |
211 | {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; |
212 | ||
213 | /* | |
214 | * Returns true if a clock update is in progress | |
215 | */ | |
216 | static inline unsigned char rtc_is_updating(void) | |
217 | { | |
0b16f21f | 218 | unsigned long flags; |
1da177e4 LT |
219 | unsigned char uip; |
220 | ||
0b16f21f | 221 | spin_lock_irqsave(&rtc_lock, flags); |
1da177e4 | 222 | uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP); |
0b16f21f | 223 | spin_unlock_irqrestore(&rtc_lock, flags); |
1da177e4 LT |
224 | return uip; |
225 | } | |
226 | ||
227 | #ifdef RTC_IRQ | |
228 | /* | |
0f2ed4c6 | 229 | * A very tiny interrupt handler. It runs with IRQF_DISABLED set, |
1da177e4 LT |
230 | * but there is possibility of conflicting with the set_rtc_mmss() |
231 | * call (the rtc irq and the timer irq can easily run at the same | |
232 | * time in two different CPUs). So we need to serialize | |
233 | * accesses to the chip with the rtc_lock spinlock that each | |
234 | * architecture should implement in the timer code. | |
235 | * (See ./arch/XXXX/kernel/time.c for the set_rtc_mmss() function.) | |
236 | */ | |
237 | ||
9580d85f | 238 | static irqreturn_t rtc_interrupt(int irq, void *dev_id) |
1da177e4 LT |
239 | { |
240 | /* | |
241 | * Can be an alarm interrupt, update complete interrupt, | |
242 | * or a periodic interrupt. We store the status in the | |
243 | * low byte and the number of interrupts received since | |
244 | * the last read in the remainder of rtc_irq_data. | |
245 | */ | |
246 | ||
5fd1fe9c | 247 | spin_lock(&rtc_lock); |
1da177e4 LT |
248 | rtc_irq_data += 0x100; |
249 | rtc_irq_data &= ~0xff; | |
250 | if (is_hpet_enabled()) { | |
251 | /* | |
252 | * In this case it is HPET RTC interrupt handler | |
253 | * calling us, with the interrupt information | |
254 | * passed as arg1, instead of irq. | |
255 | */ | |
256 | rtc_irq_data |= (unsigned long)irq & 0xF0; | |
257 | } else { | |
258 | rtc_irq_data |= (CMOS_READ(RTC_INTR_FLAGS) & 0xF0); | |
259 | } | |
260 | ||
261 | if (rtc_status & RTC_TIMER_ON) | |
262 | mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100); | |
263 | ||
5fd1fe9c | 264 | spin_unlock(&rtc_lock); |
1da177e4 LT |
265 | |
266 | /* Now do the rest of the actions */ | |
267 | spin_lock(&rtc_task_lock); | |
268 | if (rtc_callback) | |
269 | rtc_callback->func(rtc_callback->private_data); | |
270 | spin_unlock(&rtc_task_lock); | |
5fd1fe9c | 271 | wake_up_interruptible(&rtc_wait); |
1da177e4 | 272 | |
5fd1fe9c | 273 | kill_fasync(&rtc_async_queue, SIGIO, POLL_IN); |
1da177e4 LT |
274 | |
275 | return IRQ_HANDLED; | |
276 | } | |
277 | #endif | |
278 | ||
279 | /* | |
280 | * sysctl-tuning infrastructure. | |
281 | */ | |
282 | static ctl_table rtc_table[] = { | |
283 | { | |
7735362a | 284 | .ctl_name = CTL_UNNUMBERED, |
1da177e4 LT |
285 | .procname = "max-user-freq", |
286 | .data = &rtc_max_user_freq, | |
287 | .maxlen = sizeof(int), | |
288 | .mode = 0644, | |
289 | .proc_handler = &proc_dointvec, | |
290 | }, | |
291 | { .ctl_name = 0 } | |
292 | }; | |
293 | ||
294 | static ctl_table rtc_root[] = { | |
295 | { | |
7735362a | 296 | .ctl_name = CTL_UNNUMBERED, |
1da177e4 | 297 | .procname = "rtc", |
1da177e4 LT |
298 | .mode = 0555, |
299 | .child = rtc_table, | |
300 | }, | |
301 | { .ctl_name = 0 } | |
302 | }; | |
303 | ||
304 | static ctl_table dev_root[] = { | |
305 | { | |
306 | .ctl_name = CTL_DEV, | |
307 | .procname = "dev", | |
1da177e4 LT |
308 | .mode = 0555, |
309 | .child = rtc_root, | |
310 | }, | |
311 | { .ctl_name = 0 } | |
312 | }; | |
313 | ||
314 | static struct ctl_table_header *sysctl_header; | |
315 | ||
316 | static int __init init_sysctl(void) | |
317 | { | |
0b4d4147 | 318 | sysctl_header = register_sysctl_table(dev_root); |
1da177e4 LT |
319 | return 0; |
320 | } | |
321 | ||
322 | static void __exit cleanup_sysctl(void) | |
323 | { | |
324 | unregister_sysctl_table(sysctl_header); | |
325 | } | |
326 | ||
327 | /* | |
328 | * Now all the various file operations that we export. | |
329 | */ | |
330 | ||
331 | static ssize_t rtc_read(struct file *file, char __user *buf, | |
332 | size_t count, loff_t *ppos) | |
333 | { | |
334 | #ifndef RTC_IRQ | |
335 | return -EIO; | |
336 | #else | |
337 | DECLARE_WAITQUEUE(wait, current); | |
338 | unsigned long data; | |
339 | ssize_t retval; | |
5fd1fe9c | 340 | |
1da177e4 LT |
341 | if (rtc_has_irq == 0) |
342 | return -EIO; | |
343 | ||
38e0e8c0 MR |
344 | /* |
345 | * Historically this function used to assume that sizeof(unsigned long) | |
346 | * is the same in userspace and kernelspace. This lead to problems | |
347 | * for configurations with multiple ABIs such a the MIPS o32 and 64 | |
348 | * ABIs supported on the same kernel. So now we support read of both | |
349 | * 4 and 8 bytes and assume that's the sizeof(unsigned long) in the | |
350 | * userspace ABI. | |
351 | */ | |
352 | if (count != sizeof(unsigned int) && count != sizeof(unsigned long)) | |
1da177e4 LT |
353 | return -EINVAL; |
354 | ||
355 | add_wait_queue(&rtc_wait, &wait); | |
356 | ||
357 | do { | |
358 | /* First make it right. Then make it fast. Putting this whole | |
359 | * block within the parentheses of a while would be too | |
360 | * confusing. And no, xchg() is not the answer. */ | |
361 | ||
362 | __set_current_state(TASK_INTERRUPTIBLE); | |
5fd1fe9c IM |
363 | |
364 | spin_lock_irq(&rtc_lock); | |
1da177e4 LT |
365 | data = rtc_irq_data; |
366 | rtc_irq_data = 0; | |
5fd1fe9c | 367 | spin_unlock_irq(&rtc_lock); |
1da177e4 LT |
368 | |
369 | if (data != 0) | |
370 | break; | |
371 | ||
372 | if (file->f_flags & O_NONBLOCK) { | |
373 | retval = -EAGAIN; | |
374 | goto out; | |
375 | } | |
376 | if (signal_pending(current)) { | |
377 | retval = -ERESTARTSYS; | |
378 | goto out; | |
379 | } | |
380 | schedule(); | |
381 | } while (1); | |
382 | ||
5fd1fe9c IM |
383 | if (count == sizeof(unsigned int)) { |
384 | retval = put_user(data, | |
385 | (unsigned int __user *)buf) ?: sizeof(int); | |
386 | } else { | |
387 | retval = put_user(data, | |
388 | (unsigned long __user *)buf) ?: sizeof(long); | |
389 | } | |
38e0e8c0 MR |
390 | if (!retval) |
391 | retval = count; | |
1da177e4 | 392 | out: |
cc0a8fbb | 393 | __set_current_state(TASK_RUNNING); |
1da177e4 LT |
394 | remove_wait_queue(&rtc_wait, &wait); |
395 | ||
396 | return retval; | |
397 | #endif | |
398 | } | |
399 | ||
400 | static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, int kernel) | |
401 | { | |
5fd1fe9c | 402 | struct rtc_time wtime; |
1da177e4 LT |
403 | |
404 | #ifdef RTC_IRQ | |
405 | if (rtc_has_irq == 0) { | |
406 | switch (cmd) { | |
407 | case RTC_AIE_OFF: | |
408 | case RTC_AIE_ON: | |
409 | case RTC_PIE_OFF: | |
410 | case RTC_PIE_ON: | |
411 | case RTC_UIE_OFF: | |
412 | case RTC_UIE_ON: | |
413 | case RTC_IRQP_READ: | |
414 | case RTC_IRQP_SET: | |
415 | return -EINVAL; | |
416 | }; | |
417 | } | |
418 | #endif | |
419 | ||
420 | switch (cmd) { | |
421 | #ifdef RTC_IRQ | |
422 | case RTC_AIE_OFF: /* Mask alarm int. enab. bit */ | |
423 | { | |
424 | mask_rtc_irq_bit(RTC_AIE); | |
425 | return 0; | |
426 | } | |
427 | case RTC_AIE_ON: /* Allow alarm interrupts. */ | |
428 | { | |
429 | set_rtc_irq_bit(RTC_AIE); | |
430 | return 0; | |
431 | } | |
432 | case RTC_PIE_OFF: /* Mask periodic int. enab. bit */ | |
433 | { | |
5fd1fe9c IM |
434 | /* can be called from isr via rtc_control() */ |
435 | unsigned long flags; | |
436 | ||
437 | spin_lock_irqsave(&rtc_lock, flags); | |
c3348760 | 438 | mask_rtc_irq_bit_locked(RTC_PIE); |
1da177e4 | 439 | if (rtc_status & RTC_TIMER_ON) { |
1da177e4 LT |
440 | rtc_status &= ~RTC_TIMER_ON; |
441 | del_timer(&rtc_irq_timer); | |
1da177e4 | 442 | } |
5fd1fe9c IM |
443 | spin_unlock_irqrestore(&rtc_lock, flags); |
444 | ||
1da177e4 LT |
445 | return 0; |
446 | } | |
447 | case RTC_PIE_ON: /* Allow periodic ints */ | |
448 | { | |
5fd1fe9c IM |
449 | /* can be called from isr via rtc_control() */ |
450 | unsigned long flags; | |
451 | ||
1da177e4 LT |
452 | /* |
453 | * We don't really want Joe User enabling more | |
454 | * than 64Hz of interrupts on a multi-user machine. | |
455 | */ | |
456 | if (!kernel && (rtc_freq > rtc_max_user_freq) && | |
5fd1fe9c | 457 | (!capable(CAP_SYS_RESOURCE))) |
1da177e4 LT |
458 | return -EACCES; |
459 | ||
5fd1fe9c | 460 | spin_lock_irqsave(&rtc_lock, flags); |
1da177e4 | 461 | if (!(rtc_status & RTC_TIMER_ON)) { |
40565f19 JS |
462 | mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + |
463 | 2*HZ/100); | |
1da177e4 | 464 | rtc_status |= RTC_TIMER_ON; |
1da177e4 | 465 | } |
c3348760 | 466 | set_rtc_irq_bit_locked(RTC_PIE); |
5fd1fe9c IM |
467 | spin_unlock_irqrestore(&rtc_lock, flags); |
468 | ||
1da177e4 LT |
469 | return 0; |
470 | } | |
471 | case RTC_UIE_OFF: /* Mask ints from RTC updates. */ | |
472 | { | |
473 | mask_rtc_irq_bit(RTC_UIE); | |
474 | return 0; | |
475 | } | |
476 | case RTC_UIE_ON: /* Allow ints for RTC updates. */ | |
477 | { | |
478 | set_rtc_irq_bit(RTC_UIE); | |
479 | return 0; | |
480 | } | |
481 | #endif | |
482 | case RTC_ALM_READ: /* Read the present alarm time */ | |
483 | { | |
484 | /* | |
485 | * This returns a struct rtc_time. Reading >= 0xc0 | |
486 | * means "don't care" or "match all". Only the tm_hour, | |
487 | * tm_min, and tm_sec values are filled in. | |
488 | */ | |
489 | memset(&wtime, 0, sizeof(struct rtc_time)); | |
490 | get_rtc_alm_time(&wtime); | |
5fd1fe9c | 491 | break; |
1da177e4 LT |
492 | } |
493 | case RTC_ALM_SET: /* Store a time into the alarm */ | |
494 | { | |
495 | /* | |
496 | * This expects a struct rtc_time. Writing 0xff means | |
497 | * "don't care" or "match all". Only the tm_hour, | |
498 | * tm_min and tm_sec are used. | |
499 | */ | |
500 | unsigned char hrs, min, sec; | |
501 | struct rtc_time alm_tm; | |
502 | ||
503 | if (copy_from_user(&alm_tm, (struct rtc_time __user *)arg, | |
504 | sizeof(struct rtc_time))) | |
505 | return -EFAULT; | |
506 | ||
507 | hrs = alm_tm.tm_hour; | |
508 | min = alm_tm.tm_min; | |
509 | sec = alm_tm.tm_sec; | |
510 | ||
511 | spin_lock_irq(&rtc_lock); | |
512 | if (hpet_set_alarm_time(hrs, min, sec)) { | |
513 | /* | |
514 | * Fallthru and set alarm time in CMOS too, | |
515 | * so that we will get proper value in RTC_ALM_READ | |
516 | */ | |
517 | } | |
518 | if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) || | |
5fd1fe9c IM |
519 | RTC_ALWAYS_BCD) { |
520 | if (sec < 60) | |
521 | BIN_TO_BCD(sec); | |
522 | else | |
523 | sec = 0xff; | |
524 | ||
525 | if (min < 60) | |
526 | BIN_TO_BCD(min); | |
527 | else | |
528 | min = 0xff; | |
529 | ||
530 | if (hrs < 24) | |
531 | BIN_TO_BCD(hrs); | |
532 | else | |
533 | hrs = 0xff; | |
1da177e4 LT |
534 | } |
535 | CMOS_WRITE(hrs, RTC_HOURS_ALARM); | |
536 | CMOS_WRITE(min, RTC_MINUTES_ALARM); | |
537 | CMOS_WRITE(sec, RTC_SECONDS_ALARM); | |
538 | spin_unlock_irq(&rtc_lock); | |
539 | ||
540 | return 0; | |
541 | } | |
542 | case RTC_RD_TIME: /* Read the time/date from RTC */ | |
543 | { | |
544 | memset(&wtime, 0, sizeof(struct rtc_time)); | |
545 | rtc_get_rtc_time(&wtime); | |
546 | break; | |
547 | } | |
548 | case RTC_SET_TIME: /* Set the RTC */ | |
549 | { | |
550 | struct rtc_time rtc_tm; | |
551 | unsigned char mon, day, hrs, min, sec, leap_yr; | |
552 | unsigned char save_control, save_freq_select; | |
553 | unsigned int yrs; | |
554 | #ifdef CONFIG_MACH_DECSTATION | |
555 | unsigned int real_yrs; | |
556 | #endif | |
557 | ||
558 | if (!capable(CAP_SYS_TIME)) | |
559 | return -EACCES; | |
560 | ||
561 | if (copy_from_user(&rtc_tm, (struct rtc_time __user *)arg, | |
562 | sizeof(struct rtc_time))) | |
563 | return -EFAULT; | |
564 | ||
565 | yrs = rtc_tm.tm_year + 1900; | |
566 | mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */ | |
567 | day = rtc_tm.tm_mday; | |
568 | hrs = rtc_tm.tm_hour; | |
569 | min = rtc_tm.tm_min; | |
570 | sec = rtc_tm.tm_sec; | |
571 | ||
572 | if (yrs < 1970) | |
573 | return -EINVAL; | |
574 | ||
575 | leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400)); | |
576 | ||
577 | if ((mon > 12) || (day == 0)) | |
578 | return -EINVAL; | |
579 | ||
580 | if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr))) | |
581 | return -EINVAL; | |
5fd1fe9c | 582 | |
1da177e4 LT |
583 | if ((hrs >= 24) || (min >= 60) || (sec >= 60)) |
584 | return -EINVAL; | |
585 | ||
5fd1fe9c IM |
586 | yrs -= epoch; |
587 | if (yrs > 255) /* They are unsigned */ | |
1da177e4 LT |
588 | return -EINVAL; |
589 | ||
590 | spin_lock_irq(&rtc_lock); | |
591 | #ifdef CONFIG_MACH_DECSTATION | |
592 | real_yrs = yrs; | |
593 | yrs = 72; | |
594 | ||
595 | /* | |
596 | * We want to keep the year set to 73 until March | |
597 | * for non-leap years, so that Feb, 29th is handled | |
598 | * correctly. | |
599 | */ | |
600 | if (!leap_yr && mon < 3) { | |
601 | real_yrs--; | |
602 | yrs = 73; | |
603 | } | |
604 | #endif | |
605 | /* These limits and adjustments are independent of | |
606 | * whether the chip is in binary mode or not. | |
607 | */ | |
608 | if (yrs > 169) { | |
609 | spin_unlock_irq(&rtc_lock); | |
610 | return -EINVAL; | |
611 | } | |
612 | if (yrs >= 100) | |
613 | yrs -= 100; | |
614 | ||
615 | if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) | |
616 | || RTC_ALWAYS_BCD) { | |
617 | BIN_TO_BCD(sec); | |
618 | BIN_TO_BCD(min); | |
619 | BIN_TO_BCD(hrs); | |
620 | BIN_TO_BCD(day); | |
621 | BIN_TO_BCD(mon); | |
622 | BIN_TO_BCD(yrs); | |
623 | } | |
624 | ||
625 | save_control = CMOS_READ(RTC_CONTROL); | |
626 | CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL); | |
627 | save_freq_select = CMOS_READ(RTC_FREQ_SELECT); | |
628 | CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT); | |
629 | ||
630 | #ifdef CONFIG_MACH_DECSTATION | |
631 | CMOS_WRITE(real_yrs, RTC_DEC_YEAR); | |
632 | #endif | |
633 | CMOS_WRITE(yrs, RTC_YEAR); | |
634 | CMOS_WRITE(mon, RTC_MONTH); | |
635 | CMOS_WRITE(day, RTC_DAY_OF_MONTH); | |
636 | CMOS_WRITE(hrs, RTC_HOURS); | |
637 | CMOS_WRITE(min, RTC_MINUTES); | |
638 | CMOS_WRITE(sec, RTC_SECONDS); | |
639 | ||
640 | CMOS_WRITE(save_control, RTC_CONTROL); | |
641 | CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT); | |
642 | ||
643 | spin_unlock_irq(&rtc_lock); | |
644 | return 0; | |
645 | } | |
646 | #ifdef RTC_IRQ | |
647 | case RTC_IRQP_READ: /* Read the periodic IRQ rate. */ | |
648 | { | |
649 | return put_user(rtc_freq, (unsigned long __user *)arg); | |
650 | } | |
651 | case RTC_IRQP_SET: /* Set periodic IRQ rate. */ | |
652 | { | |
653 | int tmp = 0; | |
654 | unsigned char val; | |
5fd1fe9c IM |
655 | /* can be called from isr via rtc_control() */ |
656 | unsigned long flags; | |
1da177e4 | 657 | |
5fd1fe9c | 658 | /* |
1da177e4 LT |
659 | * The max we can do is 8192Hz. |
660 | */ | |
661 | if ((arg < 2) || (arg > 8192)) | |
662 | return -EINVAL; | |
663 | /* | |
664 | * We don't really want Joe User generating more | |
665 | * than 64Hz of interrupts on a multi-user machine. | |
666 | */ | |
5fd1fe9c IM |
667 | if (!kernel && (arg > rtc_max_user_freq) && |
668 | !capable(CAP_SYS_RESOURCE)) | |
1da177e4 LT |
669 | return -EACCES; |
670 | ||
671 | while (arg > (1<<tmp)) | |
672 | tmp++; | |
673 | ||
674 | /* | |
675 | * Check that the input was really a power of 2. | |
676 | */ | |
677 | if (arg != (1<<tmp)) | |
678 | return -EINVAL; | |
679 | ||
61ca9daa PG |
680 | rtc_freq = arg; |
681 | ||
c3348760 | 682 | spin_lock_irqsave(&rtc_lock, flags); |
1da177e4 | 683 | if (hpet_set_periodic_freq(arg)) { |
c3348760 | 684 | spin_unlock_irqrestore(&rtc_lock, flags); |
1da177e4 LT |
685 | return 0; |
686 | } | |
1da177e4 LT |
687 | |
688 | val = CMOS_READ(RTC_FREQ_SELECT) & 0xf0; | |
689 | val |= (16 - tmp); | |
690 | CMOS_WRITE(val, RTC_FREQ_SELECT); | |
c3348760 | 691 | spin_unlock_irqrestore(&rtc_lock, flags); |
1da177e4 LT |
692 | return 0; |
693 | } | |
694 | #endif | |
695 | case RTC_EPOCH_READ: /* Read the epoch. */ | |
696 | { | |
5fd1fe9c | 697 | return put_user(epoch, (unsigned long __user *)arg); |
1da177e4 LT |
698 | } |
699 | case RTC_EPOCH_SET: /* Set the epoch. */ | |
700 | { | |
5fd1fe9c | 701 | /* |
1da177e4 LT |
702 | * There were no RTC clocks before 1900. |
703 | */ | |
704 | if (arg < 1900) | |
705 | return -EINVAL; | |
706 | ||
707 | if (!capable(CAP_SYS_TIME)) | |
708 | return -EACCES; | |
709 | ||
710 | epoch = arg; | |
711 | return 0; | |
712 | } | |
713 | default: | |
714 | return -ENOTTY; | |
715 | } | |
5fd1fe9c IM |
716 | return copy_to_user((void __user *)arg, |
717 | &wtime, sizeof wtime) ? -EFAULT : 0; | |
1da177e4 LT |
718 | } |
719 | ||
53f1b143 | 720 | static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
1da177e4 | 721 | { |
53f1b143 AC |
722 | long ret; |
723 | lock_kernel(); | |
724 | ret = rtc_do_ioctl(cmd, arg, 0); | |
725 | unlock_kernel(); | |
726 | return ret; | |
1da177e4 LT |
727 | } |
728 | ||
729 | /* | |
730 | * We enforce only one user at a time here with the open/close. | |
731 | * Also clear the previous interrupt data on an open, and clean | |
732 | * up things on a close. | |
733 | */ | |
734 | ||
735 | /* We use rtc_lock to protect against concurrent opens. So the BKL is not | |
736 | * needed here. Or anywhere else in this driver. */ | |
737 | static int rtc_open(struct inode *inode, struct file *file) | |
738 | { | |
4333deee | 739 | lock_kernel(); |
5fd1fe9c | 740 | spin_lock_irq(&rtc_lock); |
1da177e4 | 741 | |
5fd1fe9c | 742 | if (rtc_status & RTC_IS_OPEN) |
1da177e4 LT |
743 | goto out_busy; |
744 | ||
745 | rtc_status |= RTC_IS_OPEN; | |
746 | ||
747 | rtc_irq_data = 0; | |
5fd1fe9c | 748 | spin_unlock_irq(&rtc_lock); |
4333deee | 749 | unlock_kernel(); |
1da177e4 LT |
750 | return 0; |
751 | ||
752 | out_busy: | |
5fd1fe9c | 753 | spin_unlock_irq(&rtc_lock); |
4333deee | 754 | unlock_kernel(); |
1da177e4 LT |
755 | return -EBUSY; |
756 | } | |
757 | ||
5fd1fe9c | 758 | static int rtc_fasync(int fd, struct file *filp, int on) |
1da177e4 | 759 | { |
5fd1fe9c | 760 | return fasync_helper(fd, filp, on, &rtc_async_queue); |
1da177e4 LT |
761 | } |
762 | ||
763 | static int rtc_release(struct inode *inode, struct file *file) | |
764 | { | |
765 | #ifdef RTC_IRQ | |
766 | unsigned char tmp; | |
767 | ||
768 | if (rtc_has_irq == 0) | |
769 | goto no_irq; | |
770 | ||
771 | /* | |
772 | * Turn off all interrupts once the device is no longer | |
773 | * in use, and clear the data. | |
774 | */ | |
775 | ||
776 | spin_lock_irq(&rtc_lock); | |
777 | if (!hpet_mask_rtc_irq_bit(RTC_PIE | RTC_AIE | RTC_UIE)) { | |
778 | tmp = CMOS_READ(RTC_CONTROL); | |
779 | tmp &= ~RTC_PIE; | |
780 | tmp &= ~RTC_AIE; | |
781 | tmp &= ~RTC_UIE; | |
782 | CMOS_WRITE(tmp, RTC_CONTROL); | |
783 | CMOS_READ(RTC_INTR_FLAGS); | |
784 | } | |
785 | if (rtc_status & RTC_TIMER_ON) { | |
786 | rtc_status &= ~RTC_TIMER_ON; | |
787 | del_timer(&rtc_irq_timer); | |
788 | } | |
789 | spin_unlock_irq(&rtc_lock); | |
790 | ||
5fd1fe9c IM |
791 | if (file->f_flags & FASYNC) |
792 | rtc_fasync(-1, file, 0); | |
1da177e4 LT |
793 | no_irq: |
794 | #endif | |
795 | ||
5fd1fe9c | 796 | spin_lock_irq(&rtc_lock); |
1da177e4 LT |
797 | rtc_irq_data = 0; |
798 | rtc_status &= ~RTC_IS_OPEN; | |
5fd1fe9c IM |
799 | spin_unlock_irq(&rtc_lock); |
800 | ||
1da177e4 LT |
801 | return 0; |
802 | } | |
803 | ||
804 | #ifdef RTC_IRQ | |
805 | /* Called without the kernel lock - fine */ | |
806 | static unsigned int rtc_poll(struct file *file, poll_table *wait) | |
807 | { | |
808 | unsigned long l; | |
809 | ||
810 | if (rtc_has_irq == 0) | |
811 | return 0; | |
812 | ||
813 | poll_wait(file, &rtc_wait, wait); | |
814 | ||
5fd1fe9c | 815 | spin_lock_irq(&rtc_lock); |
1da177e4 | 816 | l = rtc_irq_data; |
5fd1fe9c | 817 | spin_unlock_irq(&rtc_lock); |
1da177e4 LT |
818 | |
819 | if (l != 0) | |
820 | return POLLIN | POLLRDNORM; | |
821 | return 0; | |
822 | } | |
823 | #endif | |
824 | ||
1da177e4 LT |
825 | int rtc_register(rtc_task_t *task) |
826 | { | |
827 | #ifndef RTC_IRQ | |
828 | return -EIO; | |
829 | #else | |
830 | if (task == NULL || task->func == NULL) | |
831 | return -EINVAL; | |
832 | spin_lock_irq(&rtc_lock); | |
833 | if (rtc_status & RTC_IS_OPEN) { | |
834 | spin_unlock_irq(&rtc_lock); | |
835 | return -EBUSY; | |
836 | } | |
837 | spin_lock(&rtc_task_lock); | |
838 | if (rtc_callback) { | |
839 | spin_unlock(&rtc_task_lock); | |
840 | spin_unlock_irq(&rtc_lock); | |
841 | return -EBUSY; | |
842 | } | |
843 | rtc_status |= RTC_IS_OPEN; | |
844 | rtc_callback = task; | |
845 | spin_unlock(&rtc_task_lock); | |
846 | spin_unlock_irq(&rtc_lock); | |
847 | return 0; | |
848 | #endif | |
849 | } | |
5fd1fe9c | 850 | EXPORT_SYMBOL(rtc_register); |
1da177e4 LT |
851 | |
852 | int rtc_unregister(rtc_task_t *task) | |
853 | { | |
854 | #ifndef RTC_IRQ | |
855 | return -EIO; | |
856 | #else | |
857 | unsigned char tmp; | |
858 | ||
859 | spin_lock_irq(&rtc_lock); | |
860 | spin_lock(&rtc_task_lock); | |
861 | if (rtc_callback != task) { | |
862 | spin_unlock(&rtc_task_lock); | |
863 | spin_unlock_irq(&rtc_lock); | |
864 | return -ENXIO; | |
865 | } | |
866 | rtc_callback = NULL; | |
5fd1fe9c | 867 | |
1da177e4 LT |
868 | /* disable controls */ |
869 | if (!hpet_mask_rtc_irq_bit(RTC_PIE | RTC_AIE | RTC_UIE)) { | |
870 | tmp = CMOS_READ(RTC_CONTROL); | |
871 | tmp &= ~RTC_PIE; | |
872 | tmp &= ~RTC_AIE; | |
873 | tmp &= ~RTC_UIE; | |
874 | CMOS_WRITE(tmp, RTC_CONTROL); | |
875 | CMOS_READ(RTC_INTR_FLAGS); | |
876 | } | |
877 | if (rtc_status & RTC_TIMER_ON) { | |
878 | rtc_status &= ~RTC_TIMER_ON; | |
879 | del_timer(&rtc_irq_timer); | |
880 | } | |
881 | rtc_status &= ~RTC_IS_OPEN; | |
882 | spin_unlock(&rtc_task_lock); | |
883 | spin_unlock_irq(&rtc_lock); | |
884 | return 0; | |
885 | #endif | |
886 | } | |
5fd1fe9c | 887 | EXPORT_SYMBOL(rtc_unregister); |
1da177e4 LT |
888 | |
889 | int rtc_control(rtc_task_t *task, unsigned int cmd, unsigned long arg) | |
890 | { | |
891 | #ifndef RTC_IRQ | |
892 | return -EIO; | |
893 | #else | |
c3348760 TI |
894 | unsigned long flags; |
895 | if (cmd != RTC_PIE_ON && cmd != RTC_PIE_OFF && cmd != RTC_IRQP_SET) | |
896 | return -EINVAL; | |
897 | spin_lock_irqsave(&rtc_task_lock, flags); | |
1da177e4 | 898 | if (rtc_callback != task) { |
c3348760 | 899 | spin_unlock_irqrestore(&rtc_task_lock, flags); |
1da177e4 LT |
900 | return -ENXIO; |
901 | } | |
c3348760 | 902 | spin_unlock_irqrestore(&rtc_task_lock, flags); |
1da177e4 LT |
903 | return rtc_do_ioctl(cmd, arg, 1); |
904 | #endif | |
905 | } | |
5fd1fe9c | 906 | EXPORT_SYMBOL(rtc_control); |
1da177e4 LT |
907 | |
908 | /* | |
909 | * The various file operations we support. | |
910 | */ | |
911 | ||
62322d25 | 912 | static const struct file_operations rtc_fops = { |
1da177e4 LT |
913 | .owner = THIS_MODULE, |
914 | .llseek = no_llseek, | |
915 | .read = rtc_read, | |
916 | #ifdef RTC_IRQ | |
917 | .poll = rtc_poll, | |
918 | #endif | |
53f1b143 | 919 | .unlocked_ioctl = rtc_ioctl, |
1da177e4 LT |
920 | .open = rtc_open, |
921 | .release = rtc_release, | |
922 | .fasync = rtc_fasync, | |
923 | }; | |
924 | ||
925 | static struct miscdevice rtc_dev = { | |
926 | .minor = RTC_MINOR, | |
927 | .name = "rtc", | |
928 | .fops = &rtc_fops, | |
929 | }; | |
930 | ||
9cef779e | 931 | #ifdef CONFIG_PROC_FS |
62322d25 | 932 | static const struct file_operations rtc_proc_fops = { |
5fd1fe9c IM |
933 | .owner = THIS_MODULE, |
934 | .open = rtc_proc_open, | |
935 | .read = seq_read, | |
936 | .llseek = seq_lseek, | |
937 | .release = single_release, | |
1da177e4 | 938 | }; |
1da177e4 LT |
939 | #endif |
940 | ||
9626f1f1 BH |
941 | static resource_size_t rtc_size; |
942 | ||
943 | static struct resource * __init rtc_request_region(resource_size_t size) | |
944 | { | |
945 | struct resource *r; | |
946 | ||
947 | if (RTC_IOMAPPED) | |
948 | r = request_region(RTC_PORT(0), size, "rtc"); | |
949 | else | |
950 | r = request_mem_region(RTC_PORT(0), size, "rtc"); | |
951 | ||
952 | if (r) | |
953 | rtc_size = size; | |
954 | ||
955 | return r; | |
956 | } | |
957 | ||
4c06be10 BH |
958 | static void rtc_release_region(void) |
959 | { | |
960 | if (RTC_IOMAPPED) | |
9626f1f1 | 961 | release_region(RTC_PORT(0), rtc_size); |
4c06be10 | 962 | else |
9626f1f1 | 963 | release_mem_region(RTC_PORT(0), rtc_size); |
4c06be10 BH |
964 | } |
965 | ||
1da177e4 LT |
966 | static int __init rtc_init(void) |
967 | { | |
9cef779e | 968 | #ifdef CONFIG_PROC_FS |
1da177e4 | 969 | struct proc_dir_entry *ent; |
9cef779e | 970 | #endif |
1da177e4 LT |
971 | #if defined(__alpha__) || defined(__mips__) |
972 | unsigned int year, ctrl; | |
1da177e4 LT |
973 | char *guess = NULL; |
974 | #endif | |
cdee99d7 | 975 | #ifdef CONFIG_SPARC32 |
1da177e4 LT |
976 | struct linux_ebus *ebus; |
977 | struct linux_ebus_device *edev; | |
9cef779e | 978 | #else |
38e0e8c0 | 979 | void *r; |
9cef779e JB |
980 | #ifdef RTC_IRQ |
981 | irq_handler_t rtc_int_handler_ptr; | |
982 | #endif | |
38e0e8c0 | 983 | #endif |
1da177e4 | 984 | |
cdee99d7 | 985 | #ifdef CONFIG_SPARC32 |
1da177e4 LT |
986 | for_each_ebus(ebus) { |
987 | for_each_ebusdev(edev, ebus) { | |
5fd1fe9c | 988 | if (strcmp(edev->prom_node->name, "rtc") == 0) { |
1da177e4 LT |
989 | rtc_port = edev->resource[0].start; |
990 | rtc_irq = edev->irqs[0]; | |
991 | goto found; | |
992 | } | |
993 | } | |
994 | } | |
f3e92d35 | 995 | rtc_has_irq = 0; |
1da177e4 LT |
996 | printk(KERN_ERR "rtc_init: no PC rtc found\n"); |
997 | return -EIO; | |
998 | ||
999 | found: | |
1000 | if (rtc_irq == PCI_IRQ_NONE) { | |
1001 | rtc_has_irq = 0; | |
1002 | goto no_irq; | |
1003 | } | |
1004 | ||
1005 | /* | |
1006 | * XXX Interrupt pin #7 in Espresso is shared between RTC and | |
53d0fc27 | 1007 | * PCI Slot 2 INTA# (and some INTx# in Slot 1). |
1da177e4 | 1008 | */ |
5fd1fe9c IM |
1009 | if (request_irq(rtc_irq, rtc_interrupt, IRQF_SHARED, "rtc", |
1010 | (void *)&rtc_port)) { | |
f3e92d35 | 1011 | rtc_has_irq = 0; |
1da177e4 LT |
1012 | printk(KERN_ERR "rtc: cannot register IRQ %d\n", rtc_irq); |
1013 | return -EIO; | |
1014 | } | |
1015 | no_irq: | |
1016 | #else | |
9626f1f1 BH |
1017 | r = rtc_request_region(RTC_IO_EXTENT); |
1018 | ||
1019 | /* | |
1020 | * If we've already requested a smaller range (for example, because | |
1021 | * PNPBIOS or ACPI told us how the device is configured), the request | |
1022 | * above might fail because it's too big. | |
1023 | * | |
1024 | * If so, request just the range we actually use. | |
1025 | */ | |
1026 | if (!r) | |
1027 | r = rtc_request_region(RTC_IO_EXTENT_USED); | |
38e0e8c0 | 1028 | if (!r) { |
f3e92d35 JB |
1029 | #ifdef RTC_IRQ |
1030 | rtc_has_irq = 0; | |
1031 | #endif | |
38e0e8c0 MR |
1032 | printk(KERN_ERR "rtc: I/O resource %lx is not free.\n", |
1033 | (long)(RTC_PORT(0))); | |
1da177e4 LT |
1034 | return -EIO; |
1035 | } | |
1036 | ||
1037 | #ifdef RTC_IRQ | |
1038 | if (is_hpet_enabled()) { | |
f8f76481 BW |
1039 | int err; |
1040 | ||
1da177e4 | 1041 | rtc_int_handler_ptr = hpet_rtc_interrupt; |
f8f76481 BW |
1042 | err = hpet_register_irq_handler(rtc_interrupt); |
1043 | if (err != 0) { | |
1044 | printk(KERN_WARNING "hpet_register_irq_handler failed " | |
1045 | "in rtc_init()."); | |
1046 | return err; | |
1047 | } | |
1da177e4 LT |
1048 | } else { |
1049 | rtc_int_handler_ptr = rtc_interrupt; | |
1050 | } | |
1051 | ||
5fd1fe9c IM |
1052 | if (request_irq(RTC_IRQ, rtc_int_handler_ptr, IRQF_DISABLED, |
1053 | "rtc", NULL)) { | |
1da177e4 | 1054 | /* Yeah right, seeing as irq 8 doesn't even hit the bus. */ |
f3e92d35 | 1055 | rtc_has_irq = 0; |
1da177e4 | 1056 | printk(KERN_ERR "rtc: IRQ %d is not free.\n", RTC_IRQ); |
4c06be10 | 1057 | rtc_release_region(); |
5fd1fe9c | 1058 | |
1da177e4 LT |
1059 | return -EIO; |
1060 | } | |
1061 | hpet_rtc_timer_init(); | |
1062 | ||
1063 | #endif | |
1064 | ||
cdee99d7 | 1065 | #endif /* CONFIG_SPARC32 vs. others */ |
1da177e4 LT |
1066 | |
1067 | if (misc_register(&rtc_dev)) { | |
1068 | #ifdef RTC_IRQ | |
1069 | free_irq(RTC_IRQ, NULL); | |
f8f76481 | 1070 | hpet_unregister_irq_handler(rtc_interrupt); |
f3e92d35 | 1071 | rtc_has_irq = 0; |
1da177e4 | 1072 | #endif |
4c06be10 | 1073 | rtc_release_region(); |
1da177e4 LT |
1074 | return -ENODEV; |
1075 | } | |
1076 | ||
9cef779e | 1077 | #ifdef CONFIG_PROC_FS |
1b502217 DL |
1078 | ent = proc_create("driver/rtc", 0, NULL, &rtc_proc_fops); |
1079 | if (!ent) | |
9cef779e | 1080 | printk(KERN_WARNING "rtc: Failed to register with procfs.\n"); |
1da177e4 | 1081 | #endif |
1da177e4 LT |
1082 | |
1083 | #if defined(__alpha__) || defined(__mips__) | |
1084 | rtc_freq = HZ; | |
5fd1fe9c | 1085 | |
1da177e4 LT |
1086 | /* Each operating system on an Alpha uses its own epoch. |
1087 | Let's try to guess which one we are using now. */ | |
5fd1fe9c | 1088 | |
1da177e4 | 1089 | if (rtc_is_updating() != 0) |
47f176fd | 1090 | msleep(20); |
5fd1fe9c | 1091 | |
1da177e4 LT |
1092 | spin_lock_irq(&rtc_lock); |
1093 | year = CMOS_READ(RTC_YEAR); | |
1094 | ctrl = CMOS_READ(RTC_CONTROL); | |
1095 | spin_unlock_irq(&rtc_lock); | |
5fd1fe9c | 1096 | |
1da177e4 LT |
1097 | if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) |
1098 | BCD_TO_BIN(year); /* This should never happen... */ | |
5fd1fe9c | 1099 | |
1da177e4 LT |
1100 | if (year < 20) { |
1101 | epoch = 2000; | |
1102 | guess = "SRM (post-2000)"; | |
1103 | } else if (year >= 20 && year < 48) { | |
1104 | epoch = 1980; | |
1105 | guess = "ARC console"; | |
1106 | } else if (year >= 48 && year < 72) { | |
1107 | epoch = 1952; | |
1108 | guess = "Digital UNIX"; | |
1109 | #if defined(__mips__) | |
1110 | } else if (year >= 72 && year < 74) { | |
1111 | epoch = 2000; | |
1112 | guess = "Digital DECstation"; | |
1113 | #else | |
1114 | } else if (year >= 70) { | |
1115 | epoch = 1900; | |
1116 | guess = "Standard PC (1900)"; | |
1117 | #endif | |
1118 | } | |
1119 | if (guess) | |
5fd1fe9c IM |
1120 | printk(KERN_INFO "rtc: %s epoch (%lu) detected\n", |
1121 | guess, epoch); | |
1da177e4 LT |
1122 | #endif |
1123 | #ifdef RTC_IRQ | |
1124 | if (rtc_has_irq == 0) | |
1125 | goto no_irq2; | |
1126 | ||
1da177e4 LT |
1127 | spin_lock_irq(&rtc_lock); |
1128 | rtc_freq = 1024; | |
1129 | if (!hpet_set_periodic_freq(rtc_freq)) { | |
5fd1fe9c IM |
1130 | /* |
1131 | * Initialize periodic frequency to CMOS reset default, | |
1132 | * which is 1024Hz | |
1133 | */ | |
1134 | CMOS_WRITE(((CMOS_READ(RTC_FREQ_SELECT) & 0xF0) | 0x06), | |
1135 | RTC_FREQ_SELECT); | |
1da177e4 LT |
1136 | } |
1137 | spin_unlock_irq(&rtc_lock); | |
1138 | no_irq2: | |
1139 | #endif | |
1140 | ||
1141 | (void) init_sysctl(); | |
1142 | ||
1143 | printk(KERN_INFO "Real Time Clock Driver v" RTC_VERSION "\n"); | |
1144 | ||
1145 | return 0; | |
1146 | } | |
1147 | ||
5fd1fe9c | 1148 | static void __exit rtc_exit(void) |
1da177e4 LT |
1149 | { |
1150 | cleanup_sysctl(); | |
5fd1fe9c | 1151 | remove_proc_entry("driver/rtc", NULL); |
1da177e4 LT |
1152 | misc_deregister(&rtc_dev); |
1153 | ||
cdee99d7 | 1154 | #ifdef CONFIG_SPARC32 |
1da177e4 | 1155 | if (rtc_has_irq) |
5fd1fe9c | 1156 | free_irq(rtc_irq, &rtc_port); |
1da177e4 | 1157 | #else |
4c06be10 | 1158 | rtc_release_region(); |
1da177e4 | 1159 | #ifdef RTC_IRQ |
f8f76481 | 1160 | if (rtc_has_irq) { |
5fd1fe9c | 1161 | free_irq(RTC_IRQ, NULL); |
f8f76481 BW |
1162 | hpet_unregister_irq_handler(hpet_rtc_interrupt); |
1163 | } | |
1da177e4 | 1164 | #endif |
cdee99d7 | 1165 | #endif /* CONFIG_SPARC32 */ |
1da177e4 LT |
1166 | } |
1167 | ||
1168 | module_init(rtc_init); | |
1169 | module_exit(rtc_exit); | |
1170 | ||
1171 | #ifdef RTC_IRQ | |
1172 | /* | |
5fd1fe9c | 1173 | * At IRQ rates >= 4096Hz, an interrupt may get lost altogether. |
1da177e4 LT |
1174 | * (usually during an IDE disk interrupt, with IRQ unmasking off) |
1175 | * Since the interrupt handler doesn't get called, the IRQ status | |
1176 | * byte doesn't get read, and the RTC stops generating interrupts. | |
1177 | * A timer is set, and will call this function if/when that happens. | |
1178 | * To get it out of this stalled state, we just read the status. | |
1179 | * At least a jiffy of interrupts (rtc_freq/HZ) will have been lost. | |
5fd1fe9c | 1180 | * (You *really* shouldn't be trying to use a non-realtime system |
1da177e4 LT |
1181 | * for something that requires a steady > 1KHz signal anyways.) |
1182 | */ | |
1183 | ||
1184 | static void rtc_dropped_irq(unsigned long data) | |
1185 | { | |
1186 | unsigned long freq; | |
1187 | ||
5fd1fe9c | 1188 | spin_lock_irq(&rtc_lock); |
1da177e4 LT |
1189 | |
1190 | if (hpet_rtc_dropped_irq()) { | |
1191 | spin_unlock_irq(&rtc_lock); | |
1192 | return; | |
1193 | } | |
1194 | ||
1195 | /* Just in case someone disabled the timer from behind our back... */ | |
1196 | if (rtc_status & RTC_TIMER_ON) | |
1197 | mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100); | |
1198 | ||
1199 | rtc_irq_data += ((rtc_freq/HZ)<<8); | |
1200 | rtc_irq_data &= ~0xff; | |
1201 | rtc_irq_data |= (CMOS_READ(RTC_INTR_FLAGS) & 0xF0); /* restart */ | |
1202 | ||
1203 | freq = rtc_freq; | |
1204 | ||
1205 | spin_unlock_irq(&rtc_lock); | |
1206 | ||
5fd1fe9c IM |
1207 | if (printk_ratelimit()) { |
1208 | printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n", | |
1209 | freq); | |
1210 | } | |
1da177e4 LT |
1211 | |
1212 | /* Now we have new data */ | |
1213 | wake_up_interruptible(&rtc_wait); | |
1214 | ||
5fd1fe9c | 1215 | kill_fasync(&rtc_async_queue, SIGIO, POLL_IN); |
1da177e4 LT |
1216 | } |
1217 | #endif | |
1218 | ||
9cef779e | 1219 | #ifdef CONFIG_PROC_FS |
1da177e4 LT |
1220 | /* |
1221 | * Info exported via "/proc/driver/rtc". | |
1222 | */ | |
1223 | ||
1224 | static int rtc_proc_show(struct seq_file *seq, void *v) | |
1225 | { | |
1226 | #define YN(bit) ((ctrl & bit) ? "yes" : "no") | |
1227 | #define NY(bit) ((ctrl & bit) ? "no" : "yes") | |
1228 | struct rtc_time tm; | |
1229 | unsigned char batt, ctrl; | |
1230 | unsigned long freq; | |
1231 | ||
1232 | spin_lock_irq(&rtc_lock); | |
1233 | batt = CMOS_READ(RTC_VALID) & RTC_VRT; | |
1234 | ctrl = CMOS_READ(RTC_CONTROL); | |
1235 | freq = rtc_freq; | |
1236 | spin_unlock_irq(&rtc_lock); | |
1237 | ||
1238 | ||
1239 | rtc_get_rtc_time(&tm); | |
1240 | ||
1241 | /* | |
1242 | * There is no way to tell if the luser has the RTC set for local | |
1243 | * time or for Universal Standard Time (GMT). Probably local though. | |
1244 | */ | |
1245 | seq_printf(seq, | |
1246 | "rtc_time\t: %02d:%02d:%02d\n" | |
1247 | "rtc_date\t: %04d-%02d-%02d\n" | |
1248 | "rtc_epoch\t: %04lu\n", | |
1249 | tm.tm_hour, tm.tm_min, tm.tm_sec, | |
1250 | tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, epoch); | |
1251 | ||
1252 | get_rtc_alm_time(&tm); | |
1253 | ||
1254 | /* | |
1255 | * We implicitly assume 24hr mode here. Alarm values >= 0xc0 will | |
1256 | * match any value for that particular field. Values that are | |
1257 | * greater than a valid time, but less than 0xc0 shouldn't appear. | |
1258 | */ | |
1259 | seq_puts(seq, "alarm\t\t: "); | |
1260 | if (tm.tm_hour <= 24) | |
1261 | seq_printf(seq, "%02d:", tm.tm_hour); | |
1262 | else | |
1263 | seq_puts(seq, "**:"); | |
1264 | ||
1265 | if (tm.tm_min <= 59) | |
1266 | seq_printf(seq, "%02d:", tm.tm_min); | |
1267 | else | |
1268 | seq_puts(seq, "**:"); | |
1269 | ||
1270 | if (tm.tm_sec <= 59) | |
1271 | seq_printf(seq, "%02d\n", tm.tm_sec); | |
1272 | else | |
1273 | seq_puts(seq, "**\n"); | |
1274 | ||
1275 | seq_printf(seq, | |
1276 | "DST_enable\t: %s\n" | |
1277 | "BCD\t\t: %s\n" | |
1278 | "24hr\t\t: %s\n" | |
1279 | "square_wave\t: %s\n" | |
1280 | "alarm_IRQ\t: %s\n" | |
1281 | "update_IRQ\t: %s\n" | |
1282 | "periodic_IRQ\t: %s\n" | |
1283 | "periodic_freq\t: %ld\n" | |
1284 | "batt_status\t: %s\n", | |
1285 | YN(RTC_DST_EN), | |
1286 | NY(RTC_DM_BINARY), | |
1287 | YN(RTC_24H), | |
1288 | YN(RTC_SQWE), | |
1289 | YN(RTC_AIE), | |
1290 | YN(RTC_UIE), | |
1291 | YN(RTC_PIE), | |
1292 | freq, | |
1293 | batt ? "okay" : "dead"); | |
1294 | ||
1295 | return 0; | |
1296 | #undef YN | |
1297 | #undef NY | |
1298 | } | |
1299 | ||
1300 | static int rtc_proc_open(struct inode *inode, struct file *file) | |
1301 | { | |
1302 | return single_open(file, rtc_proc_show, NULL); | |
1303 | } | |
9cef779e | 1304 | #endif |
1da177e4 | 1305 | |
9580d85f | 1306 | static void rtc_get_rtc_time(struct rtc_time *rtc_tm) |
1da177e4 | 1307 | { |
0f749646 | 1308 | unsigned long uip_watchdog = jiffies, flags; |
1da177e4 LT |
1309 | unsigned char ctrl; |
1310 | #ifdef CONFIG_MACH_DECSTATION | |
1311 | unsigned int real_year; | |
1312 | #endif | |
1313 | ||
1314 | /* | |
1315 | * read RTC once any update in progress is done. The update | |
47f176fd | 1316 | * can take just over 2ms. We wait 20ms. There is no need to |
1da177e4 LT |
1317 | * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP. |
1318 | * If you need to know *exactly* when a second has started, enable | |
5fd1fe9c | 1319 | * periodic update complete interrupts, (via ioctl) and then |
1da177e4 LT |
1320 | * immediately read /dev/rtc which will block until you get the IRQ. |
1321 | * Once the read clears, read the RTC time (again via ioctl). Easy. | |
1322 | */ | |
1323 | ||
dca03a51 JL |
1324 | while (rtc_is_updating() != 0 && |
1325 | time_before(jiffies, uip_watchdog + 2*HZ/100)) | |
403fe5ae | 1326 | cpu_relax(); |
1da177e4 LT |
1327 | |
1328 | /* | |
1329 | * Only the values that we read from the RTC are set. We leave | |
b7599587 AC |
1330 | * tm_wday, tm_yday and tm_isdst untouched. Note that while the |
1331 | * RTC has RTC_DAY_OF_WEEK, we should usually ignore it, as it is | |
1332 | * only updated by the RTC when initially set to a non-zero value. | |
1da177e4 | 1333 | */ |
0f749646 | 1334 | spin_lock_irqsave(&rtc_lock, flags); |
1da177e4 LT |
1335 | rtc_tm->tm_sec = CMOS_READ(RTC_SECONDS); |
1336 | rtc_tm->tm_min = CMOS_READ(RTC_MINUTES); | |
1337 | rtc_tm->tm_hour = CMOS_READ(RTC_HOURS); | |
1338 | rtc_tm->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH); | |
1339 | rtc_tm->tm_mon = CMOS_READ(RTC_MONTH); | |
1340 | rtc_tm->tm_year = CMOS_READ(RTC_YEAR); | |
b7599587 AC |
1341 | /* Only set from 2.6.16 onwards */ |
1342 | rtc_tm->tm_wday = CMOS_READ(RTC_DAY_OF_WEEK); | |
1343 | ||
1da177e4 LT |
1344 | #ifdef CONFIG_MACH_DECSTATION |
1345 | real_year = CMOS_READ(RTC_DEC_YEAR); | |
1346 | #endif | |
1347 | ctrl = CMOS_READ(RTC_CONTROL); | |
0f749646 | 1348 | spin_unlock_irqrestore(&rtc_lock, flags); |
1da177e4 | 1349 | |
5fd1fe9c | 1350 | if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { |
1da177e4 LT |
1351 | BCD_TO_BIN(rtc_tm->tm_sec); |
1352 | BCD_TO_BIN(rtc_tm->tm_min); | |
1353 | BCD_TO_BIN(rtc_tm->tm_hour); | |
1354 | BCD_TO_BIN(rtc_tm->tm_mday); | |
1355 | BCD_TO_BIN(rtc_tm->tm_mon); | |
1356 | BCD_TO_BIN(rtc_tm->tm_year); | |
b7599587 | 1357 | BCD_TO_BIN(rtc_tm->tm_wday); |
1da177e4 LT |
1358 | } |
1359 | ||
1360 | #ifdef CONFIG_MACH_DECSTATION | |
1361 | rtc_tm->tm_year += real_year - 72; | |
1362 | #endif | |
1363 | ||
1364 | /* | |
1365 | * Account for differences between how the RTC uses the values | |
1366 | * and how they are defined in a struct rtc_time; | |
1367 | */ | |
5fd1fe9c IM |
1368 | rtc_tm->tm_year += epoch - 1900; |
1369 | if (rtc_tm->tm_year <= 69) | |
1da177e4 LT |
1370 | rtc_tm->tm_year += 100; |
1371 | ||
1372 | rtc_tm->tm_mon--; | |
1373 | } | |
1374 | ||
1375 | static void get_rtc_alm_time(struct rtc_time *alm_tm) | |
1376 | { | |
1377 | unsigned char ctrl; | |
1378 | ||
1379 | /* | |
1380 | * Only the values that we read from the RTC are set. That | |
1381 | * means only tm_hour, tm_min, and tm_sec. | |
1382 | */ | |
1383 | spin_lock_irq(&rtc_lock); | |
1384 | alm_tm->tm_sec = CMOS_READ(RTC_SECONDS_ALARM); | |
1385 | alm_tm->tm_min = CMOS_READ(RTC_MINUTES_ALARM); | |
1386 | alm_tm->tm_hour = CMOS_READ(RTC_HOURS_ALARM); | |
1387 | ctrl = CMOS_READ(RTC_CONTROL); | |
1388 | spin_unlock_irq(&rtc_lock); | |
1389 | ||
5fd1fe9c | 1390 | if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { |
1da177e4 LT |
1391 | BCD_TO_BIN(alm_tm->tm_sec); |
1392 | BCD_TO_BIN(alm_tm->tm_min); | |
1393 | BCD_TO_BIN(alm_tm->tm_hour); | |
1394 | } | |
1395 | } | |
1396 | ||
1397 | #ifdef RTC_IRQ | |
1398 | /* | |
1399 | * Used to disable/enable interrupts for any one of UIE, AIE, PIE. | |
1400 | * Rumour has it that if you frob the interrupt enable/disable | |
1401 | * bits in RTC_CONTROL, you should read RTC_INTR_FLAGS, to | |
1402 | * ensure you actually start getting interrupts. Probably for | |
1403 | * compatibility with older/broken chipset RTC implementations. | |
1404 | * We also clear out any old irq data after an ioctl() that | |
1405 | * meddles with the interrupt enable/disable bits. | |
1406 | */ | |
1407 | ||
c3348760 | 1408 | static void mask_rtc_irq_bit_locked(unsigned char bit) |
1da177e4 LT |
1409 | { |
1410 | unsigned char val; | |
1411 | ||
c3348760 | 1412 | if (hpet_mask_rtc_irq_bit(bit)) |
1da177e4 | 1413 | return; |
1da177e4 LT |
1414 | val = CMOS_READ(RTC_CONTROL); |
1415 | val &= ~bit; | |
1416 | CMOS_WRITE(val, RTC_CONTROL); | |
1417 | CMOS_READ(RTC_INTR_FLAGS); | |
1418 | ||
1419 | rtc_irq_data = 0; | |
1da177e4 LT |
1420 | } |
1421 | ||
c3348760 | 1422 | static void set_rtc_irq_bit_locked(unsigned char bit) |
1da177e4 LT |
1423 | { |
1424 | unsigned char val; | |
1425 | ||
c3348760 | 1426 | if (hpet_set_rtc_irq_bit(bit)) |
1da177e4 | 1427 | return; |
1da177e4 LT |
1428 | val = CMOS_READ(RTC_CONTROL); |
1429 | val |= bit; | |
1430 | CMOS_WRITE(val, RTC_CONTROL); | |
1431 | CMOS_READ(RTC_INTR_FLAGS); | |
1432 | ||
1433 | rtc_irq_data = 0; | |
1da177e4 LT |
1434 | } |
1435 | #endif | |
1436 | ||
1437 | MODULE_AUTHOR("Paul Gortmaker"); | |
1438 | MODULE_LICENSE("GPL"); | |
1439 | MODULE_ALIAS_MISCDEV(RTC_MINOR); |