Commit | Line | Data |
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2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 | 2 | /* |
5fd1fe9c | 3 | * Real Time Clock interface for Linux |
1da177e4 LT |
4 | * |
5 | * Copyright (C) 1996 Paul Gortmaker | |
6 | * | |
7 | * This driver allows use of the real time clock (built into | |
8 | * nearly all computers) from user space. It exports the /dev/rtc | |
9 | * interface supporting various ioctl() and also the | |
10 | * /proc/driver/rtc pseudo-file for status information. | |
11 | * | |
12 | * The ioctls can be used to set the interrupt behaviour and | |
13 | * generation rate from the RTC via IRQ 8. Then the /dev/rtc | |
14 | * interface can be used to make use of these timer interrupts, | |
15 | * be they interval or alarm based. | |
16 | * | |
17 | * The /dev/rtc interface will block on reads until an interrupt | |
18 | * has been received. If a RTC interrupt has already happened, | |
19 | * it will output an unsigned long and then block. The output value | |
20 | * contains the interrupt status in the low byte and the number of | |
5fd1fe9c | 21 | * interrupts since the last read in the remaining high bytes. The |
1da177e4 LT |
22 | * /dev/rtc interface can also be used with the select(2) call. |
23 | * | |
1da177e4 LT |
24 | * Based on other minimal char device drivers, like Alan's |
25 | * watchdog, Ted's random, etc. etc. | |
26 | * | |
27 | * 1.07 Paul Gortmaker. | |
28 | * 1.08 Miquel van Smoorenburg: disallow certain things on the | |
29 | * DEC Alpha as the CMOS clock is also used for other things. | |
30 | * 1.09 Nikita Schmidt: epoch support and some Alpha cleanup. | |
31 | * 1.09a Pete Zaitcev: Sun SPARC | |
32 | * 1.09b Jeff Garzik: Modularize, init cleanup | |
33 | * 1.09c Jeff Garzik: SMP cleanup | |
12a0a703 | 34 | * 1.10 Paul Barton-Davis: add support for async I/O |
1da177e4 LT |
35 | * 1.10a Andrea Arcangeli: Alpha updates |
36 | * 1.10b Andrew Morton: SMP lock fix | |
37 | * 1.10c Cesar Barros: SMP locking fixes and cleanup | |
38 | * 1.10d Paul Gortmaker: delete paranoia check in rtc_exit | |
39 | * 1.10e Maciej W. Rozycki: Handle DECstation's year weirdness. | |
12a0a703 | 40 | * 1.11 Takashi Iwai: Kernel access functions |
1da177e4 LT |
41 | * rtc_register/rtc_unregister/rtc_control |
42 | * 1.11a Daniele Bellucci: Audit create_proc_read_entry in rtc_init | |
43 | * 1.12 Venkatesh Pallipadi: Hooks for emulating rtc on HPET base-timer | |
44 | * CONFIG_HPET_EMULATE_RTC | |
38e0e8c0 | 45 | * 1.12a Maciej W. Rozycki: Handle memory-mapped chips properly. |
b7599587 | 46 | * 1.12ac Alan Cox: Allow read access to the day of week register |
048cd588 | 47 | * 1.12b David John: Remove calls to the BKL. |
1da177e4 LT |
48 | */ |
49 | ||
048cd588 | 50 | #define RTC_VERSION "1.12b" |
1da177e4 | 51 | |
1da177e4 LT |
52 | /* |
53 | * Note that *all* calls to CMOS_READ and CMOS_WRITE are done with | |
54 | * interrupts disabled. Due to the index-port/data-port (0x70/0x71) | |
55 | * design of the RTC, we don't want two different things trying to | |
5196d203 MW |
56 | * get to it at once. (e.g. the periodic 11 min sync from |
57 | * kernel/time/ntp.c vs. this driver.) | |
1da177e4 LT |
58 | */ |
59 | ||
1da177e4 LT |
60 | #include <linux/interrupt.h> |
61 | #include <linux/module.h> | |
62 | #include <linux/kernel.h> | |
63 | #include <linux/types.h> | |
64 | #include <linux/miscdevice.h> | |
65 | #include <linux/ioport.h> | |
66 | #include <linux/fcntl.h> | |
67 | #include <linux/mc146818rtc.h> | |
68 | #include <linux/init.h> | |
69 | #include <linux/poll.h> | |
70 | #include <linux/proc_fs.h> | |
71 | #include <linux/seq_file.h> | |
72 | #include <linux/spinlock.h> | |
174cd4b1 | 73 | #include <linux/sched/signal.h> |
1da177e4 LT |
74 | #include <linux/sysctl.h> |
75 | #include <linux/wait.h> | |
76 | #include <linux/bcd.h> | |
47f176fd | 77 | #include <linux/delay.h> |
53f1b143 | 78 | #include <linux/uaccess.h> |
a28ee477 | 79 | #include <linux/ratelimit.h> |
1da177e4 LT |
80 | |
81 | #include <asm/current.h> | |
1da177e4 | 82 | |
55f93afd | 83 | #ifdef CONFIG_X86 |
1da177e4 LT |
84 | #include <asm/hpet.h> |
85 | #endif | |
86 | ||
cdee99d7 | 87 | #ifdef CONFIG_SPARC32 |
75081322 DM |
88 | #include <linux/of.h> |
89 | #include <linux/of_device.h> | |
90 | #include <asm/io.h> | |
1da177e4 LT |
91 | |
92 | static unsigned long rtc_port; | |
75081322 | 93 | static int rtc_irq; |
1da177e4 LT |
94 | #endif |
95 | ||
0f4d3fd8 | 96 | #ifdef CONFIG_HPET_EMULATE_RTC |
1da177e4 LT |
97 | #undef RTC_IRQ |
98 | #endif | |
99 | ||
100 | #ifdef RTC_IRQ | |
101 | static int rtc_has_irq = 1; | |
102 | #endif | |
103 | ||
104 | #ifndef CONFIG_HPET_EMULATE_RTC | |
105 | #define is_hpet_enabled() 0 | |
5fd1fe9c IM |
106 | #define hpet_set_alarm_time(hrs, min, sec) 0 |
107 | #define hpet_set_periodic_freq(arg) 0 | |
108 | #define hpet_mask_rtc_irq_bit(arg) 0 | |
109 | #define hpet_set_rtc_irq_bit(arg) 0 | |
110 | #define hpet_rtc_timer_init() do { } while (0) | |
111 | #define hpet_rtc_dropped_irq() 0 | |
32fa4586 DH |
112 | #define hpet_register_irq_handler(h) ({ 0; }) |
113 | #define hpet_unregister_irq_handler(h) ({ 0; }) | |
533ffc28 AM |
114 | #ifdef RTC_IRQ |
115 | static irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id) | |
116 | { | |
117 | return 0; | |
118 | } | |
119 | #endif | |
1da177e4 LT |
120 | #endif |
121 | ||
122 | /* | |
123 | * We sponge a minor off of the misc major. No need slurping | |
124 | * up another valuable major dev number for this. If you add | |
125 | * an ioctl, make sure you don't conflict with SPARC's RTC | |
126 | * ioctls. | |
127 | */ | |
128 | ||
129 | static struct fasync_struct *rtc_async_queue; | |
130 | ||
131 | static DECLARE_WAIT_QUEUE_HEAD(rtc_wait); | |
132 | ||
133 | #ifdef RTC_IRQ | |
24ed960a | 134 | static void rtc_dropped_irq(struct timer_list *unused); |
40565f19 | 135 | |
1d27e3e2 | 136 | static DEFINE_TIMER(rtc_irq_timer, rtc_dropped_irq); |
1da177e4 LT |
137 | #endif |
138 | ||
139 | static ssize_t rtc_read(struct file *file, char __user *buf, | |
140 | size_t count, loff_t *ppos); | |
141 | ||
53f1b143 | 142 | static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg); |
9580d85f | 143 | static void rtc_get_rtc_time(struct rtc_time *rtc_tm); |
1da177e4 LT |
144 | |
145 | #ifdef RTC_IRQ | |
afc9a42b | 146 | static __poll_t rtc_poll(struct file *file, poll_table *wait); |
1da177e4 LT |
147 | #endif |
148 | ||
5fd1fe9c | 149 | static void get_rtc_alm_time(struct rtc_time *alm_tm); |
1da177e4 | 150 | #ifdef RTC_IRQ |
c3348760 TI |
151 | static void set_rtc_irq_bit_locked(unsigned char bit); |
152 | static void mask_rtc_irq_bit_locked(unsigned char bit); | |
153 | ||
154 | static inline void set_rtc_irq_bit(unsigned char bit) | |
155 | { | |
156 | spin_lock_irq(&rtc_lock); | |
157 | set_rtc_irq_bit_locked(bit); | |
158 | spin_unlock_irq(&rtc_lock); | |
159 | } | |
160 | ||
161 | static void mask_rtc_irq_bit(unsigned char bit) | |
162 | { | |
163 | spin_lock_irq(&rtc_lock); | |
164 | mask_rtc_irq_bit_locked(bit); | |
165 | spin_unlock_irq(&rtc_lock); | |
166 | } | |
1da177e4 LT |
167 | #endif |
168 | ||
9cef779e | 169 | #ifdef CONFIG_PROC_FS |
3f3942ac | 170 | static int rtc_proc_show(struct seq_file *seq, void *v); |
9cef779e | 171 | #endif |
1da177e4 LT |
172 | |
173 | /* | |
174 | * Bits in rtc_status. (6 bits of room for future expansion) | |
175 | */ | |
176 | ||
177 | #define RTC_IS_OPEN 0x01 /* means /dev/rtc is in use */ | |
178 | #define RTC_TIMER_ON 0x02 /* missed irq timer active */ | |
179 | ||
180 | /* | |
181 | * rtc_status is never changed by rtc_interrupt, and ioctl/open/close is | |
048cd588 DJ |
182 | * protected by the spin lock rtc_lock. However, ioctl can still disable the |
183 | * timer in rtc_status and then with del_timer after the interrupt has read | |
1da177e4 LT |
184 | * rtc_status but before mod_timer is called, which would then reenable the |
185 | * timer (but you would need to have an awful timing before you'd trip on it) | |
186 | */ | |
5fd1fe9c IM |
187 | static unsigned long rtc_status; /* bitmapped status byte. */ |
188 | static unsigned long rtc_freq; /* Current periodic IRQ rate */ | |
189 | static unsigned long rtc_irq_data; /* our output to the world */ | |
1da177e4 LT |
190 | static unsigned long rtc_max_user_freq = 64; /* > this, need CAP_SYS_RESOURCE */ |
191 | ||
1da177e4 LT |
192 | /* |
193 | * If this driver ever becomes modularised, it will be really nice | |
194 | * to make the epoch retain its value across module reload... | |
195 | */ | |
196 | ||
197 | static unsigned long epoch = 1900; /* year corresponding to 0x00 */ | |
198 | ||
5fd1fe9c | 199 | static const unsigned char days_in_mo[] = |
1da177e4 LT |
200 | {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; |
201 | ||
202 | /* | |
203 | * Returns true if a clock update is in progress | |
204 | */ | |
205 | static inline unsigned char rtc_is_updating(void) | |
206 | { | |
0b16f21f | 207 | unsigned long flags; |
1da177e4 LT |
208 | unsigned char uip; |
209 | ||
0b16f21f | 210 | spin_lock_irqsave(&rtc_lock, flags); |
1da177e4 | 211 | uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP); |
0b16f21f | 212 | spin_unlock_irqrestore(&rtc_lock, flags); |
1da177e4 LT |
213 | return uip; |
214 | } | |
215 | ||
216 | #ifdef RTC_IRQ | |
217 | /* | |
d88ed628 | 218 | * A very tiny interrupt handler. It runs with interrupts disabled, |
1da177e4 LT |
219 | * but there is possibility of conflicting with the set_rtc_mmss() |
220 | * call (the rtc irq and the timer irq can easily run at the same | |
221 | * time in two different CPUs). So we need to serialize | |
222 | * accesses to the chip with the rtc_lock spinlock that each | |
223 | * architecture should implement in the timer code. | |
224 | * (See ./arch/XXXX/kernel/time.c for the set_rtc_mmss() function.) | |
225 | */ | |
226 | ||
9580d85f | 227 | static irqreturn_t rtc_interrupt(int irq, void *dev_id) |
1da177e4 LT |
228 | { |
229 | /* | |
230 | * Can be an alarm interrupt, update complete interrupt, | |
231 | * or a periodic interrupt. We store the status in the | |
232 | * low byte and the number of interrupts received since | |
233 | * the last read in the remainder of rtc_irq_data. | |
234 | */ | |
235 | ||
5fd1fe9c | 236 | spin_lock(&rtc_lock); |
1da177e4 LT |
237 | rtc_irq_data += 0x100; |
238 | rtc_irq_data &= ~0xff; | |
239 | if (is_hpet_enabled()) { | |
240 | /* | |
241 | * In this case it is HPET RTC interrupt handler | |
242 | * calling us, with the interrupt information | |
243 | * passed as arg1, instead of irq. | |
244 | */ | |
245 | rtc_irq_data |= (unsigned long)irq & 0xF0; | |
246 | } else { | |
247 | rtc_irq_data |= (CMOS_READ(RTC_INTR_FLAGS) & 0xF0); | |
248 | } | |
249 | ||
250 | if (rtc_status & RTC_TIMER_ON) | |
251 | mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100); | |
252 | ||
5fd1fe9c | 253 | spin_unlock(&rtc_lock); |
1da177e4 | 254 | |
5fd1fe9c | 255 | wake_up_interruptible(&rtc_wait); |
1da177e4 | 256 | |
5fd1fe9c | 257 | kill_fasync(&rtc_async_queue, SIGIO, POLL_IN); |
1da177e4 LT |
258 | |
259 | return IRQ_HANDLED; | |
260 | } | |
261 | #endif | |
262 | ||
263 | /* | |
264 | * sysctl-tuning infrastructure. | |
265 | */ | |
a151427e | 266 | static struct ctl_table rtc_table[] = { |
1da177e4 | 267 | { |
1da177e4 LT |
268 | .procname = "max-user-freq", |
269 | .data = &rtc_max_user_freq, | |
270 | .maxlen = sizeof(int), | |
271 | .mode = 0644, | |
6d456111 | 272 | .proc_handler = proc_dointvec, |
1da177e4 | 273 | }, |
894d2491 | 274 | { } |
1da177e4 LT |
275 | }; |
276 | ||
a151427e | 277 | static struct ctl_table rtc_root[] = { |
1da177e4 | 278 | { |
1da177e4 | 279 | .procname = "rtc", |
1da177e4 LT |
280 | .mode = 0555, |
281 | .child = rtc_table, | |
282 | }, | |
894d2491 | 283 | { } |
1da177e4 LT |
284 | }; |
285 | ||
a151427e | 286 | static struct ctl_table dev_root[] = { |
1da177e4 | 287 | { |
1da177e4 | 288 | .procname = "dev", |
1da177e4 LT |
289 | .mode = 0555, |
290 | .child = rtc_root, | |
291 | }, | |
894d2491 | 292 | { } |
1da177e4 LT |
293 | }; |
294 | ||
295 | static struct ctl_table_header *sysctl_header; | |
296 | ||
297 | static int __init init_sysctl(void) | |
298 | { | |
0b4d4147 | 299 | sysctl_header = register_sysctl_table(dev_root); |
1da177e4 LT |
300 | return 0; |
301 | } | |
302 | ||
303 | static void __exit cleanup_sysctl(void) | |
304 | { | |
305 | unregister_sysctl_table(sysctl_header); | |
306 | } | |
307 | ||
308 | /* | |
309 | * Now all the various file operations that we export. | |
310 | */ | |
311 | ||
312 | static ssize_t rtc_read(struct file *file, char __user *buf, | |
313 | size_t count, loff_t *ppos) | |
314 | { | |
315 | #ifndef RTC_IRQ | |
316 | return -EIO; | |
317 | #else | |
318 | DECLARE_WAITQUEUE(wait, current); | |
319 | unsigned long data; | |
320 | ssize_t retval; | |
5fd1fe9c | 321 | |
1da177e4 LT |
322 | if (rtc_has_irq == 0) |
323 | return -EIO; | |
324 | ||
38e0e8c0 MR |
325 | /* |
326 | * Historically this function used to assume that sizeof(unsigned long) | |
327 | * is the same in userspace and kernelspace. This lead to problems | |
328 | * for configurations with multiple ABIs such a the MIPS o32 and 64 | |
329 | * ABIs supported on the same kernel. So now we support read of both | |
330 | * 4 and 8 bytes and assume that's the sizeof(unsigned long) in the | |
331 | * userspace ABI. | |
332 | */ | |
333 | if (count != sizeof(unsigned int) && count != sizeof(unsigned long)) | |
1da177e4 LT |
334 | return -EINVAL; |
335 | ||
336 | add_wait_queue(&rtc_wait, &wait); | |
337 | ||
338 | do { | |
339 | /* First make it right. Then make it fast. Putting this whole | |
340 | * block within the parentheses of a while would be too | |
341 | * confusing. And no, xchg() is not the answer. */ | |
342 | ||
343 | __set_current_state(TASK_INTERRUPTIBLE); | |
5fd1fe9c IM |
344 | |
345 | spin_lock_irq(&rtc_lock); | |
1da177e4 LT |
346 | data = rtc_irq_data; |
347 | rtc_irq_data = 0; | |
5fd1fe9c | 348 | spin_unlock_irq(&rtc_lock); |
1da177e4 LT |
349 | |
350 | if (data != 0) | |
351 | break; | |
352 | ||
353 | if (file->f_flags & O_NONBLOCK) { | |
354 | retval = -EAGAIN; | |
355 | goto out; | |
356 | } | |
357 | if (signal_pending(current)) { | |
358 | retval = -ERESTARTSYS; | |
359 | goto out; | |
360 | } | |
361 | schedule(); | |
362 | } while (1); | |
363 | ||
5fd1fe9c IM |
364 | if (count == sizeof(unsigned int)) { |
365 | retval = put_user(data, | |
366 | (unsigned int __user *)buf) ?: sizeof(int); | |
367 | } else { | |
368 | retval = put_user(data, | |
369 | (unsigned long __user *)buf) ?: sizeof(long); | |
370 | } | |
38e0e8c0 MR |
371 | if (!retval) |
372 | retval = count; | |
1da177e4 | 373 | out: |
cc0a8fbb | 374 | __set_current_state(TASK_RUNNING); |
1da177e4 LT |
375 | remove_wait_queue(&rtc_wait, &wait); |
376 | ||
377 | return retval; | |
378 | #endif | |
379 | } | |
380 | ||
381 | static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, int kernel) | |
382 | { | |
5fd1fe9c | 383 | struct rtc_time wtime; |
1da177e4 LT |
384 | |
385 | #ifdef RTC_IRQ | |
386 | if (rtc_has_irq == 0) { | |
387 | switch (cmd) { | |
388 | case RTC_AIE_OFF: | |
389 | case RTC_AIE_ON: | |
390 | case RTC_PIE_OFF: | |
391 | case RTC_PIE_ON: | |
392 | case RTC_UIE_OFF: | |
393 | case RTC_UIE_ON: | |
394 | case RTC_IRQP_READ: | |
395 | case RTC_IRQP_SET: | |
396 | return -EINVAL; | |
f8885c26 | 397 | } |
1da177e4 LT |
398 | } |
399 | #endif | |
400 | ||
401 | switch (cmd) { | |
402 | #ifdef RTC_IRQ | |
403 | case RTC_AIE_OFF: /* Mask alarm int. enab. bit */ | |
404 | { | |
405 | mask_rtc_irq_bit(RTC_AIE); | |
406 | return 0; | |
407 | } | |
408 | case RTC_AIE_ON: /* Allow alarm interrupts. */ | |
409 | { | |
410 | set_rtc_irq_bit(RTC_AIE); | |
411 | return 0; | |
412 | } | |
413 | case RTC_PIE_OFF: /* Mask periodic int. enab. bit */ | |
414 | { | |
5fd1fe9c IM |
415 | /* can be called from isr via rtc_control() */ |
416 | unsigned long flags; | |
417 | ||
418 | spin_lock_irqsave(&rtc_lock, flags); | |
c3348760 | 419 | mask_rtc_irq_bit_locked(RTC_PIE); |
1da177e4 | 420 | if (rtc_status & RTC_TIMER_ON) { |
1da177e4 LT |
421 | rtc_status &= ~RTC_TIMER_ON; |
422 | del_timer(&rtc_irq_timer); | |
1da177e4 | 423 | } |
5fd1fe9c IM |
424 | spin_unlock_irqrestore(&rtc_lock, flags); |
425 | ||
1da177e4 LT |
426 | return 0; |
427 | } | |
428 | case RTC_PIE_ON: /* Allow periodic ints */ | |
429 | { | |
5fd1fe9c IM |
430 | /* can be called from isr via rtc_control() */ |
431 | unsigned long flags; | |
432 | ||
1da177e4 LT |
433 | /* |
434 | * We don't really want Joe User enabling more | |
435 | * than 64Hz of interrupts on a multi-user machine. | |
436 | */ | |
437 | if (!kernel && (rtc_freq > rtc_max_user_freq) && | |
5fd1fe9c | 438 | (!capable(CAP_SYS_RESOURCE))) |
1da177e4 LT |
439 | return -EACCES; |
440 | ||
5fd1fe9c | 441 | spin_lock_irqsave(&rtc_lock, flags); |
1da177e4 | 442 | if (!(rtc_status & RTC_TIMER_ON)) { |
40565f19 JS |
443 | mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + |
444 | 2*HZ/100); | |
1da177e4 | 445 | rtc_status |= RTC_TIMER_ON; |
1da177e4 | 446 | } |
c3348760 | 447 | set_rtc_irq_bit_locked(RTC_PIE); |
5fd1fe9c IM |
448 | spin_unlock_irqrestore(&rtc_lock, flags); |
449 | ||
1da177e4 LT |
450 | return 0; |
451 | } | |
452 | case RTC_UIE_OFF: /* Mask ints from RTC updates. */ | |
453 | { | |
454 | mask_rtc_irq_bit(RTC_UIE); | |
455 | return 0; | |
456 | } | |
457 | case RTC_UIE_ON: /* Allow ints for RTC updates. */ | |
458 | { | |
459 | set_rtc_irq_bit(RTC_UIE); | |
460 | return 0; | |
461 | } | |
462 | #endif | |
463 | case RTC_ALM_READ: /* Read the present alarm time */ | |
464 | { | |
465 | /* | |
466 | * This returns a struct rtc_time. Reading >= 0xc0 | |
467 | * means "don't care" or "match all". Only the tm_hour, | |
468 | * tm_min, and tm_sec values are filled in. | |
469 | */ | |
470 | memset(&wtime, 0, sizeof(struct rtc_time)); | |
471 | get_rtc_alm_time(&wtime); | |
5fd1fe9c | 472 | break; |
1da177e4 LT |
473 | } |
474 | case RTC_ALM_SET: /* Store a time into the alarm */ | |
475 | { | |
476 | /* | |
477 | * This expects a struct rtc_time. Writing 0xff means | |
478 | * "don't care" or "match all". Only the tm_hour, | |
479 | * tm_min and tm_sec are used. | |
480 | */ | |
481 | unsigned char hrs, min, sec; | |
482 | struct rtc_time alm_tm; | |
483 | ||
484 | if (copy_from_user(&alm_tm, (struct rtc_time __user *)arg, | |
485 | sizeof(struct rtc_time))) | |
486 | return -EFAULT; | |
487 | ||
488 | hrs = alm_tm.tm_hour; | |
489 | min = alm_tm.tm_min; | |
490 | sec = alm_tm.tm_sec; | |
491 | ||
492 | spin_lock_irq(&rtc_lock); | |
493 | if (hpet_set_alarm_time(hrs, min, sec)) { | |
494 | /* | |
495 | * Fallthru and set alarm time in CMOS too, | |
496 | * so that we will get proper value in RTC_ALM_READ | |
497 | */ | |
498 | } | |
499 | if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) || | |
5fd1fe9c IM |
500 | RTC_ALWAYS_BCD) { |
501 | if (sec < 60) | |
357c6e63 | 502 | sec = bin2bcd(sec); |
5fd1fe9c IM |
503 | else |
504 | sec = 0xff; | |
505 | ||
506 | if (min < 60) | |
357c6e63 | 507 | min = bin2bcd(min); |
5fd1fe9c IM |
508 | else |
509 | min = 0xff; | |
510 | ||
511 | if (hrs < 24) | |
357c6e63 | 512 | hrs = bin2bcd(hrs); |
5fd1fe9c IM |
513 | else |
514 | hrs = 0xff; | |
1da177e4 LT |
515 | } |
516 | CMOS_WRITE(hrs, RTC_HOURS_ALARM); | |
517 | CMOS_WRITE(min, RTC_MINUTES_ALARM); | |
518 | CMOS_WRITE(sec, RTC_SECONDS_ALARM); | |
519 | spin_unlock_irq(&rtc_lock); | |
520 | ||
521 | return 0; | |
522 | } | |
523 | case RTC_RD_TIME: /* Read the time/date from RTC */ | |
524 | { | |
525 | memset(&wtime, 0, sizeof(struct rtc_time)); | |
526 | rtc_get_rtc_time(&wtime); | |
527 | break; | |
528 | } | |
529 | case RTC_SET_TIME: /* Set the RTC */ | |
530 | { | |
531 | struct rtc_time rtc_tm; | |
532 | unsigned char mon, day, hrs, min, sec, leap_yr; | |
533 | unsigned char save_control, save_freq_select; | |
534 | unsigned int yrs; | |
535 | #ifdef CONFIG_MACH_DECSTATION | |
536 | unsigned int real_yrs; | |
537 | #endif | |
538 | ||
539 | if (!capable(CAP_SYS_TIME)) | |
540 | return -EACCES; | |
541 | ||
542 | if (copy_from_user(&rtc_tm, (struct rtc_time __user *)arg, | |
543 | sizeof(struct rtc_time))) | |
544 | return -EFAULT; | |
545 | ||
546 | yrs = rtc_tm.tm_year + 1900; | |
547 | mon = rtc_tm.tm_mon + 1; /* tm_mon starts at zero */ | |
548 | day = rtc_tm.tm_mday; | |
549 | hrs = rtc_tm.tm_hour; | |
550 | min = rtc_tm.tm_min; | |
551 | sec = rtc_tm.tm_sec; | |
552 | ||
553 | if (yrs < 1970) | |
554 | return -EINVAL; | |
555 | ||
556 | leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400)); | |
557 | ||
558 | if ((mon > 12) || (day == 0)) | |
559 | return -EINVAL; | |
560 | ||
561 | if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr))) | |
562 | return -EINVAL; | |
5fd1fe9c | 563 | |
1da177e4 LT |
564 | if ((hrs >= 24) || (min >= 60) || (sec >= 60)) |
565 | return -EINVAL; | |
566 | ||
5fd1fe9c IM |
567 | yrs -= epoch; |
568 | if (yrs > 255) /* They are unsigned */ | |
1da177e4 LT |
569 | return -EINVAL; |
570 | ||
571 | spin_lock_irq(&rtc_lock); | |
572 | #ifdef CONFIG_MACH_DECSTATION | |
573 | real_yrs = yrs; | |
574 | yrs = 72; | |
575 | ||
576 | /* | |
577 | * We want to keep the year set to 73 until March | |
578 | * for non-leap years, so that Feb, 29th is handled | |
579 | * correctly. | |
580 | */ | |
581 | if (!leap_yr && mon < 3) { | |
582 | real_yrs--; | |
583 | yrs = 73; | |
584 | } | |
585 | #endif | |
586 | /* These limits and adjustments are independent of | |
587 | * whether the chip is in binary mode or not. | |
588 | */ | |
589 | if (yrs > 169) { | |
590 | spin_unlock_irq(&rtc_lock); | |
591 | return -EINVAL; | |
592 | } | |
593 | if (yrs >= 100) | |
594 | yrs -= 100; | |
595 | ||
596 | if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) | |
597 | || RTC_ALWAYS_BCD) { | |
357c6e63 AB |
598 | sec = bin2bcd(sec); |
599 | min = bin2bcd(min); | |
600 | hrs = bin2bcd(hrs); | |
601 | day = bin2bcd(day); | |
602 | mon = bin2bcd(mon); | |
603 | yrs = bin2bcd(yrs); | |
1da177e4 LT |
604 | } |
605 | ||
606 | save_control = CMOS_READ(RTC_CONTROL); | |
607 | CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL); | |
608 | save_freq_select = CMOS_READ(RTC_FREQ_SELECT); | |
609 | CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT); | |
610 | ||
611 | #ifdef CONFIG_MACH_DECSTATION | |
612 | CMOS_WRITE(real_yrs, RTC_DEC_YEAR); | |
613 | #endif | |
614 | CMOS_WRITE(yrs, RTC_YEAR); | |
615 | CMOS_WRITE(mon, RTC_MONTH); | |
616 | CMOS_WRITE(day, RTC_DAY_OF_MONTH); | |
617 | CMOS_WRITE(hrs, RTC_HOURS); | |
618 | CMOS_WRITE(min, RTC_MINUTES); | |
619 | CMOS_WRITE(sec, RTC_SECONDS); | |
620 | ||
621 | CMOS_WRITE(save_control, RTC_CONTROL); | |
622 | CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT); | |
623 | ||
624 | spin_unlock_irq(&rtc_lock); | |
625 | return 0; | |
626 | } | |
627 | #ifdef RTC_IRQ | |
628 | case RTC_IRQP_READ: /* Read the periodic IRQ rate. */ | |
629 | { | |
630 | return put_user(rtc_freq, (unsigned long __user *)arg); | |
631 | } | |
632 | case RTC_IRQP_SET: /* Set periodic IRQ rate. */ | |
633 | { | |
634 | int tmp = 0; | |
635 | unsigned char val; | |
5fd1fe9c IM |
636 | /* can be called from isr via rtc_control() */ |
637 | unsigned long flags; | |
1da177e4 | 638 | |
5fd1fe9c | 639 | /* |
1da177e4 LT |
640 | * The max we can do is 8192Hz. |
641 | */ | |
642 | if ((arg < 2) || (arg > 8192)) | |
643 | return -EINVAL; | |
644 | /* | |
645 | * We don't really want Joe User generating more | |
646 | * than 64Hz of interrupts on a multi-user machine. | |
647 | */ | |
5fd1fe9c IM |
648 | if (!kernel && (arg > rtc_max_user_freq) && |
649 | !capable(CAP_SYS_RESOURCE)) | |
1da177e4 LT |
650 | return -EACCES; |
651 | ||
652 | while (arg > (1<<tmp)) | |
653 | tmp++; | |
654 | ||
655 | /* | |
656 | * Check that the input was really a power of 2. | |
657 | */ | |
658 | if (arg != (1<<tmp)) | |
659 | return -EINVAL; | |
660 | ||
61ca9daa PG |
661 | rtc_freq = arg; |
662 | ||
c3348760 | 663 | spin_lock_irqsave(&rtc_lock, flags); |
1da177e4 | 664 | if (hpet_set_periodic_freq(arg)) { |
c3348760 | 665 | spin_unlock_irqrestore(&rtc_lock, flags); |
1da177e4 LT |
666 | return 0; |
667 | } | |
1da177e4 LT |
668 | |
669 | val = CMOS_READ(RTC_FREQ_SELECT) & 0xf0; | |
670 | val |= (16 - tmp); | |
671 | CMOS_WRITE(val, RTC_FREQ_SELECT); | |
c3348760 | 672 | spin_unlock_irqrestore(&rtc_lock, flags); |
1da177e4 LT |
673 | return 0; |
674 | } | |
675 | #endif | |
676 | case RTC_EPOCH_READ: /* Read the epoch. */ | |
677 | { | |
5fd1fe9c | 678 | return put_user(epoch, (unsigned long __user *)arg); |
1da177e4 LT |
679 | } |
680 | case RTC_EPOCH_SET: /* Set the epoch. */ | |
681 | { | |
5fd1fe9c | 682 | /* |
1da177e4 LT |
683 | * There were no RTC clocks before 1900. |
684 | */ | |
685 | if (arg < 1900) | |
686 | return -EINVAL; | |
687 | ||
688 | if (!capable(CAP_SYS_TIME)) | |
689 | return -EACCES; | |
690 | ||
691 | epoch = arg; | |
692 | return 0; | |
693 | } | |
694 | default: | |
695 | return -ENOTTY; | |
696 | } | |
5fd1fe9c IM |
697 | return copy_to_user((void __user *)arg, |
698 | &wtime, sizeof wtime) ? -EFAULT : 0; | |
1da177e4 LT |
699 | } |
700 | ||
53f1b143 | 701 | static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
1da177e4 | 702 | { |
53f1b143 | 703 | long ret; |
53f1b143 | 704 | ret = rtc_do_ioctl(cmd, arg, 0); |
53f1b143 | 705 | return ret; |
1da177e4 LT |
706 | } |
707 | ||
708 | /* | |
709 | * We enforce only one user at a time here with the open/close. | |
710 | * Also clear the previous interrupt data on an open, and clean | |
711 | * up things on a close. | |
712 | */ | |
1da177e4 LT |
713 | static int rtc_open(struct inode *inode, struct file *file) |
714 | { | |
5fd1fe9c | 715 | spin_lock_irq(&rtc_lock); |
1da177e4 | 716 | |
5fd1fe9c | 717 | if (rtc_status & RTC_IS_OPEN) |
1da177e4 LT |
718 | goto out_busy; |
719 | ||
720 | rtc_status |= RTC_IS_OPEN; | |
721 | ||
722 | rtc_irq_data = 0; | |
5fd1fe9c | 723 | spin_unlock_irq(&rtc_lock); |
1da177e4 LT |
724 | return 0; |
725 | ||
726 | out_busy: | |
5fd1fe9c | 727 | spin_unlock_irq(&rtc_lock); |
1da177e4 LT |
728 | return -EBUSY; |
729 | } | |
730 | ||
5fd1fe9c | 731 | static int rtc_fasync(int fd, struct file *filp, int on) |
1da177e4 | 732 | { |
5fd1fe9c | 733 | return fasync_helper(fd, filp, on, &rtc_async_queue); |
1da177e4 LT |
734 | } |
735 | ||
736 | static int rtc_release(struct inode *inode, struct file *file) | |
737 | { | |
738 | #ifdef RTC_IRQ | |
739 | unsigned char tmp; | |
740 | ||
741 | if (rtc_has_irq == 0) | |
742 | goto no_irq; | |
743 | ||
744 | /* | |
745 | * Turn off all interrupts once the device is no longer | |
746 | * in use, and clear the data. | |
747 | */ | |
748 | ||
749 | spin_lock_irq(&rtc_lock); | |
750 | if (!hpet_mask_rtc_irq_bit(RTC_PIE | RTC_AIE | RTC_UIE)) { | |
751 | tmp = CMOS_READ(RTC_CONTROL); | |
752 | tmp &= ~RTC_PIE; | |
753 | tmp &= ~RTC_AIE; | |
754 | tmp &= ~RTC_UIE; | |
755 | CMOS_WRITE(tmp, RTC_CONTROL); | |
756 | CMOS_READ(RTC_INTR_FLAGS); | |
757 | } | |
758 | if (rtc_status & RTC_TIMER_ON) { | |
759 | rtc_status &= ~RTC_TIMER_ON; | |
760 | del_timer(&rtc_irq_timer); | |
761 | } | |
762 | spin_unlock_irq(&rtc_lock); | |
763 | ||
1da177e4 LT |
764 | no_irq: |
765 | #endif | |
766 | ||
5fd1fe9c | 767 | spin_lock_irq(&rtc_lock); |
1da177e4 LT |
768 | rtc_irq_data = 0; |
769 | rtc_status &= ~RTC_IS_OPEN; | |
5fd1fe9c IM |
770 | spin_unlock_irq(&rtc_lock); |
771 | ||
1da177e4 LT |
772 | return 0; |
773 | } | |
774 | ||
775 | #ifdef RTC_IRQ | |
afc9a42b | 776 | static __poll_t rtc_poll(struct file *file, poll_table *wait) |
1da177e4 LT |
777 | { |
778 | unsigned long l; | |
779 | ||
780 | if (rtc_has_irq == 0) | |
781 | return 0; | |
782 | ||
783 | poll_wait(file, &rtc_wait, wait); | |
784 | ||
5fd1fe9c | 785 | spin_lock_irq(&rtc_lock); |
1da177e4 | 786 | l = rtc_irq_data; |
5fd1fe9c | 787 | spin_unlock_irq(&rtc_lock); |
1da177e4 LT |
788 | |
789 | if (l != 0) | |
a9a08845 | 790 | return EPOLLIN | EPOLLRDNORM; |
1da177e4 LT |
791 | return 0; |
792 | } | |
793 | #endif | |
794 | ||
1da177e4 LT |
795 | /* |
796 | * The various file operations we support. | |
797 | */ | |
798 | ||
62322d25 | 799 | static const struct file_operations rtc_fops = { |
1da177e4 LT |
800 | .owner = THIS_MODULE, |
801 | .llseek = no_llseek, | |
802 | .read = rtc_read, | |
803 | #ifdef RTC_IRQ | |
804 | .poll = rtc_poll, | |
805 | #endif | |
53f1b143 | 806 | .unlocked_ioctl = rtc_ioctl, |
1da177e4 LT |
807 | .open = rtc_open, |
808 | .release = rtc_release, | |
809 | .fasync = rtc_fasync, | |
810 | }; | |
811 | ||
812 | static struct miscdevice rtc_dev = { | |
813 | .minor = RTC_MINOR, | |
814 | .name = "rtc", | |
815 | .fops = &rtc_fops, | |
816 | }; | |
817 | ||
9626f1f1 BH |
818 | static resource_size_t rtc_size; |
819 | ||
820 | static struct resource * __init rtc_request_region(resource_size_t size) | |
821 | { | |
822 | struct resource *r; | |
823 | ||
824 | if (RTC_IOMAPPED) | |
825 | r = request_region(RTC_PORT(0), size, "rtc"); | |
826 | else | |
827 | r = request_mem_region(RTC_PORT(0), size, "rtc"); | |
828 | ||
829 | if (r) | |
830 | rtc_size = size; | |
831 | ||
832 | return r; | |
833 | } | |
834 | ||
4c06be10 BH |
835 | static void rtc_release_region(void) |
836 | { | |
837 | if (RTC_IOMAPPED) | |
9626f1f1 | 838 | release_region(RTC_PORT(0), rtc_size); |
4c06be10 | 839 | else |
9626f1f1 | 840 | release_mem_region(RTC_PORT(0), rtc_size); |
4c06be10 BH |
841 | } |
842 | ||
1da177e4 LT |
843 | static int __init rtc_init(void) |
844 | { | |
9cef779e | 845 | #ifdef CONFIG_PROC_FS |
1da177e4 | 846 | struct proc_dir_entry *ent; |
9cef779e | 847 | #endif |
1da177e4 LT |
848 | #if defined(__alpha__) || defined(__mips__) |
849 | unsigned int year, ctrl; | |
1da177e4 LT |
850 | char *guess = NULL; |
851 | #endif | |
cdee99d7 | 852 | #ifdef CONFIG_SPARC32 |
75081322 | 853 | struct device_node *ebus_dp; |
2dc11581 | 854 | struct platform_device *op; |
9cef779e | 855 | #else |
38e0e8c0 | 856 | void *r; |
9cef779e JB |
857 | #ifdef RTC_IRQ |
858 | irq_handler_t rtc_int_handler_ptr; | |
859 | #endif | |
38e0e8c0 | 860 | #endif |
1da177e4 | 861 | |
cdee99d7 | 862 | #ifdef CONFIG_SPARC32 |
75081322 DM |
863 | for_each_node_by_name(ebus_dp, "ebus") { |
864 | struct device_node *dp; | |
f88fd666 RH |
865 | for_each_child_of_node(ebus_dp, dp) { |
866 | if (of_node_name_eq(dp, "rtc")) { | |
75081322 DM |
867 | op = of_find_device_by_node(dp); |
868 | if (op) { | |
869 | rtc_port = op->resource[0].start; | |
870 | rtc_irq = op->irqs[0]; | |
871 | goto found; | |
872 | } | |
1da177e4 LT |
873 | } |
874 | } | |
875 | } | |
f3e92d35 | 876 | rtc_has_irq = 0; |
1da177e4 LT |
877 | printk(KERN_ERR "rtc_init: no PC rtc found\n"); |
878 | return -EIO; | |
879 | ||
880 | found: | |
75081322 | 881 | if (!rtc_irq) { |
1da177e4 LT |
882 | rtc_has_irq = 0; |
883 | goto no_irq; | |
884 | } | |
885 | ||
886 | /* | |
887 | * XXX Interrupt pin #7 in Espresso is shared between RTC and | |
53d0fc27 | 888 | * PCI Slot 2 INTA# (and some INTx# in Slot 1). |
1da177e4 | 889 | */ |
5fd1fe9c IM |
890 | if (request_irq(rtc_irq, rtc_interrupt, IRQF_SHARED, "rtc", |
891 | (void *)&rtc_port)) { | |
f3e92d35 | 892 | rtc_has_irq = 0; |
1da177e4 LT |
893 | printk(KERN_ERR "rtc: cannot register IRQ %d\n", rtc_irq); |
894 | return -EIO; | |
895 | } | |
896 | no_irq: | |
897 | #else | |
9626f1f1 BH |
898 | r = rtc_request_region(RTC_IO_EXTENT); |
899 | ||
900 | /* | |
901 | * If we've already requested a smaller range (for example, because | |
902 | * PNPBIOS or ACPI told us how the device is configured), the request | |
903 | * above might fail because it's too big. | |
904 | * | |
905 | * If so, request just the range we actually use. | |
906 | */ | |
907 | if (!r) | |
908 | r = rtc_request_region(RTC_IO_EXTENT_USED); | |
38e0e8c0 | 909 | if (!r) { |
f3e92d35 JB |
910 | #ifdef RTC_IRQ |
911 | rtc_has_irq = 0; | |
912 | #endif | |
38e0e8c0 MR |
913 | printk(KERN_ERR "rtc: I/O resource %lx is not free.\n", |
914 | (long)(RTC_PORT(0))); | |
1da177e4 LT |
915 | return -EIO; |
916 | } | |
917 | ||
918 | #ifdef RTC_IRQ | |
919 | if (is_hpet_enabled()) { | |
f8f76481 BW |
920 | int err; |
921 | ||
1da177e4 | 922 | rtc_int_handler_ptr = hpet_rtc_interrupt; |
f8f76481 BW |
923 | err = hpet_register_irq_handler(rtc_interrupt); |
924 | if (err != 0) { | |
925 | printk(KERN_WARNING "hpet_register_irq_handler failed " | |
926 | "in rtc_init()."); | |
927 | return err; | |
928 | } | |
1da177e4 LT |
929 | } else { |
930 | rtc_int_handler_ptr = rtc_interrupt; | |
931 | } | |
932 | ||
d88ed628 | 933 | if (request_irq(RTC_IRQ, rtc_int_handler_ptr, 0, "rtc", NULL)) { |
1da177e4 | 934 | /* Yeah right, seeing as irq 8 doesn't even hit the bus. */ |
f3e92d35 | 935 | rtc_has_irq = 0; |
1da177e4 | 936 | printk(KERN_ERR "rtc: IRQ %d is not free.\n", RTC_IRQ); |
4c06be10 | 937 | rtc_release_region(); |
5fd1fe9c | 938 | |
1da177e4 LT |
939 | return -EIO; |
940 | } | |
941 | hpet_rtc_timer_init(); | |
942 | ||
943 | #endif | |
944 | ||
cdee99d7 | 945 | #endif /* CONFIG_SPARC32 vs. others */ |
1da177e4 LT |
946 | |
947 | if (misc_register(&rtc_dev)) { | |
948 | #ifdef RTC_IRQ | |
949 | free_irq(RTC_IRQ, NULL); | |
f8f76481 | 950 | hpet_unregister_irq_handler(rtc_interrupt); |
f3e92d35 | 951 | rtc_has_irq = 0; |
1da177e4 | 952 | #endif |
4c06be10 | 953 | rtc_release_region(); |
1da177e4 LT |
954 | return -ENODEV; |
955 | } | |
956 | ||
9cef779e | 957 | #ifdef CONFIG_PROC_FS |
3f3942ac | 958 | ent = proc_create_single("driver/rtc", 0, NULL, rtc_proc_show); |
1b502217 | 959 | if (!ent) |
9cef779e | 960 | printk(KERN_WARNING "rtc: Failed to register with procfs.\n"); |
1da177e4 | 961 | #endif |
1da177e4 LT |
962 | |
963 | #if defined(__alpha__) || defined(__mips__) | |
964 | rtc_freq = HZ; | |
5fd1fe9c | 965 | |
1da177e4 LT |
966 | /* Each operating system on an Alpha uses its own epoch. |
967 | Let's try to guess which one we are using now. */ | |
5fd1fe9c | 968 | |
1da177e4 | 969 | if (rtc_is_updating() != 0) |
47f176fd | 970 | msleep(20); |
5fd1fe9c | 971 | |
1da177e4 LT |
972 | spin_lock_irq(&rtc_lock); |
973 | year = CMOS_READ(RTC_YEAR); | |
974 | ctrl = CMOS_READ(RTC_CONTROL); | |
975 | spin_unlock_irq(&rtc_lock); | |
5fd1fe9c | 976 | |
1da177e4 | 977 | if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) |
357c6e63 | 978 | year = bcd2bin(year); /* This should never happen... */ |
5fd1fe9c | 979 | |
1da177e4 LT |
980 | if (year < 20) { |
981 | epoch = 2000; | |
982 | guess = "SRM (post-2000)"; | |
983 | } else if (year >= 20 && year < 48) { | |
984 | epoch = 1980; | |
985 | guess = "ARC console"; | |
986 | } else if (year >= 48 && year < 72) { | |
987 | epoch = 1952; | |
988 | guess = "Digital UNIX"; | |
989 | #if defined(__mips__) | |
990 | } else if (year >= 72 && year < 74) { | |
991 | epoch = 2000; | |
992 | guess = "Digital DECstation"; | |
993 | #else | |
994 | } else if (year >= 70) { | |
995 | epoch = 1900; | |
996 | guess = "Standard PC (1900)"; | |
997 | #endif | |
998 | } | |
999 | if (guess) | |
5fd1fe9c IM |
1000 | printk(KERN_INFO "rtc: %s epoch (%lu) detected\n", |
1001 | guess, epoch); | |
1da177e4 LT |
1002 | #endif |
1003 | #ifdef RTC_IRQ | |
1004 | if (rtc_has_irq == 0) | |
1005 | goto no_irq2; | |
1006 | ||
1da177e4 LT |
1007 | spin_lock_irq(&rtc_lock); |
1008 | rtc_freq = 1024; | |
1009 | if (!hpet_set_periodic_freq(rtc_freq)) { | |
5fd1fe9c IM |
1010 | /* |
1011 | * Initialize periodic frequency to CMOS reset default, | |
1012 | * which is 1024Hz | |
1013 | */ | |
1014 | CMOS_WRITE(((CMOS_READ(RTC_FREQ_SELECT) & 0xF0) | 0x06), | |
1015 | RTC_FREQ_SELECT); | |
1da177e4 LT |
1016 | } |
1017 | spin_unlock_irq(&rtc_lock); | |
1018 | no_irq2: | |
1019 | #endif | |
1020 | ||
1021 | (void) init_sysctl(); | |
1022 | ||
1023 | printk(KERN_INFO "Real Time Clock Driver v" RTC_VERSION "\n"); | |
1024 | ||
1025 | return 0; | |
1026 | } | |
1027 | ||
5fd1fe9c | 1028 | static void __exit rtc_exit(void) |
1da177e4 LT |
1029 | { |
1030 | cleanup_sysctl(); | |
5fd1fe9c | 1031 | remove_proc_entry("driver/rtc", NULL); |
1da177e4 LT |
1032 | misc_deregister(&rtc_dev); |
1033 | ||
cdee99d7 | 1034 | #ifdef CONFIG_SPARC32 |
1da177e4 | 1035 | if (rtc_has_irq) |
5fd1fe9c | 1036 | free_irq(rtc_irq, &rtc_port); |
1da177e4 | 1037 | #else |
4c06be10 | 1038 | rtc_release_region(); |
1da177e4 | 1039 | #ifdef RTC_IRQ |
f8f76481 | 1040 | if (rtc_has_irq) { |
5fd1fe9c | 1041 | free_irq(RTC_IRQ, NULL); |
f8f76481 BW |
1042 | hpet_unregister_irq_handler(hpet_rtc_interrupt); |
1043 | } | |
1da177e4 | 1044 | #endif |
cdee99d7 | 1045 | #endif /* CONFIG_SPARC32 */ |
1da177e4 LT |
1046 | } |
1047 | ||
1048 | module_init(rtc_init); | |
1049 | module_exit(rtc_exit); | |
1050 | ||
1051 | #ifdef RTC_IRQ | |
1052 | /* | |
5fd1fe9c | 1053 | * At IRQ rates >= 4096Hz, an interrupt may get lost altogether. |
1da177e4 LT |
1054 | * (usually during an IDE disk interrupt, with IRQ unmasking off) |
1055 | * Since the interrupt handler doesn't get called, the IRQ status | |
1056 | * byte doesn't get read, and the RTC stops generating interrupts. | |
1057 | * A timer is set, and will call this function if/when that happens. | |
1058 | * To get it out of this stalled state, we just read the status. | |
1059 | * At least a jiffy of interrupts (rtc_freq/HZ) will have been lost. | |
5fd1fe9c | 1060 | * (You *really* shouldn't be trying to use a non-realtime system |
1da177e4 LT |
1061 | * for something that requires a steady > 1KHz signal anyways.) |
1062 | */ | |
1063 | ||
24ed960a | 1064 | static void rtc_dropped_irq(struct timer_list *unused) |
1da177e4 LT |
1065 | { |
1066 | unsigned long freq; | |
1067 | ||
5fd1fe9c | 1068 | spin_lock_irq(&rtc_lock); |
1da177e4 LT |
1069 | |
1070 | if (hpet_rtc_dropped_irq()) { | |
1071 | spin_unlock_irq(&rtc_lock); | |
1072 | return; | |
1073 | } | |
1074 | ||
1075 | /* Just in case someone disabled the timer from behind our back... */ | |
1076 | if (rtc_status & RTC_TIMER_ON) | |
1077 | mod_timer(&rtc_irq_timer, jiffies + HZ/rtc_freq + 2*HZ/100); | |
1078 | ||
1079 | rtc_irq_data += ((rtc_freq/HZ)<<8); | |
1080 | rtc_irq_data &= ~0xff; | |
1081 | rtc_irq_data |= (CMOS_READ(RTC_INTR_FLAGS) & 0xF0); /* restart */ | |
1082 | ||
1083 | freq = rtc_freq; | |
1084 | ||
1085 | spin_unlock_irq(&rtc_lock); | |
1086 | ||
a28ee477 CD |
1087 | printk_ratelimited(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n", |
1088 | freq); | |
1da177e4 LT |
1089 | |
1090 | /* Now we have new data */ | |
1091 | wake_up_interruptible(&rtc_wait); | |
1092 | ||
5fd1fe9c | 1093 | kill_fasync(&rtc_async_queue, SIGIO, POLL_IN); |
1da177e4 LT |
1094 | } |
1095 | #endif | |
1096 | ||
9cef779e | 1097 | #ifdef CONFIG_PROC_FS |
1da177e4 LT |
1098 | /* |
1099 | * Info exported via "/proc/driver/rtc". | |
1100 | */ | |
1101 | ||
1102 | static int rtc_proc_show(struct seq_file *seq, void *v) | |
1103 | { | |
1104 | #define YN(bit) ((ctrl & bit) ? "yes" : "no") | |
1105 | #define NY(bit) ((ctrl & bit) ? "no" : "yes") | |
1106 | struct rtc_time tm; | |
1107 | unsigned char batt, ctrl; | |
1108 | unsigned long freq; | |
1109 | ||
1110 | spin_lock_irq(&rtc_lock); | |
1111 | batt = CMOS_READ(RTC_VALID) & RTC_VRT; | |
1112 | ctrl = CMOS_READ(RTC_CONTROL); | |
1113 | freq = rtc_freq; | |
1114 | spin_unlock_irq(&rtc_lock); | |
1115 | ||
1116 | ||
1117 | rtc_get_rtc_time(&tm); | |
1118 | ||
1119 | /* | |
1120 | * There is no way to tell if the luser has the RTC set for local | |
1121 | * time or for Universal Standard Time (GMT). Probably local though. | |
1122 | */ | |
1123 | seq_printf(seq, | |
5548cbf7 AS |
1124 | "rtc_time\t: %ptRt\n" |
1125 | "rtc_date\t: %ptRd\n" | |
1da177e4 | 1126 | "rtc_epoch\t: %04lu\n", |
5548cbf7 | 1127 | &tm, &tm, epoch); |
1da177e4 LT |
1128 | |
1129 | get_rtc_alm_time(&tm); | |
1130 | ||
1131 | /* | |
1132 | * We implicitly assume 24hr mode here. Alarm values >= 0xc0 will | |
1133 | * match any value for that particular field. Values that are | |
1134 | * greater than a valid time, but less than 0xc0 shouldn't appear. | |
1135 | */ | |
1136 | seq_puts(seq, "alarm\t\t: "); | |
1137 | if (tm.tm_hour <= 24) | |
1138 | seq_printf(seq, "%02d:", tm.tm_hour); | |
1139 | else | |
1140 | seq_puts(seq, "**:"); | |
1141 | ||
1142 | if (tm.tm_min <= 59) | |
1143 | seq_printf(seq, "%02d:", tm.tm_min); | |
1144 | else | |
1145 | seq_puts(seq, "**:"); | |
1146 | ||
1147 | if (tm.tm_sec <= 59) | |
1148 | seq_printf(seq, "%02d\n", tm.tm_sec); | |
1149 | else | |
1150 | seq_puts(seq, "**\n"); | |
1151 | ||
1152 | seq_printf(seq, | |
1153 | "DST_enable\t: %s\n" | |
1154 | "BCD\t\t: %s\n" | |
1155 | "24hr\t\t: %s\n" | |
1156 | "square_wave\t: %s\n" | |
1157 | "alarm_IRQ\t: %s\n" | |
1158 | "update_IRQ\t: %s\n" | |
1159 | "periodic_IRQ\t: %s\n" | |
1160 | "periodic_freq\t: %ld\n" | |
1161 | "batt_status\t: %s\n", | |
1162 | YN(RTC_DST_EN), | |
1163 | NY(RTC_DM_BINARY), | |
1164 | YN(RTC_24H), | |
1165 | YN(RTC_SQWE), | |
1166 | YN(RTC_AIE), | |
1167 | YN(RTC_UIE), | |
1168 | YN(RTC_PIE), | |
1169 | freq, | |
1170 | batt ? "okay" : "dead"); | |
1171 | ||
1172 | return 0; | |
1173 | #undef YN | |
1174 | #undef NY | |
1175 | } | |
9cef779e | 1176 | #endif |
1da177e4 | 1177 | |
9580d85f | 1178 | static void rtc_get_rtc_time(struct rtc_time *rtc_tm) |
1da177e4 | 1179 | { |
0f749646 | 1180 | unsigned long uip_watchdog = jiffies, flags; |
1da177e4 LT |
1181 | unsigned char ctrl; |
1182 | #ifdef CONFIG_MACH_DECSTATION | |
1183 | unsigned int real_year; | |
1184 | #endif | |
1185 | ||
1186 | /* | |
1187 | * read RTC once any update in progress is done. The update | |
47f176fd | 1188 | * can take just over 2ms. We wait 20ms. There is no need to |
1da177e4 LT |
1189 | * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP. |
1190 | * If you need to know *exactly* when a second has started, enable | |
5fd1fe9c | 1191 | * periodic update complete interrupts, (via ioctl) and then |
1da177e4 LT |
1192 | * immediately read /dev/rtc which will block until you get the IRQ. |
1193 | * Once the read clears, read the RTC time (again via ioctl). Easy. | |
1194 | */ | |
1195 | ||
dca03a51 JL |
1196 | while (rtc_is_updating() != 0 && |
1197 | time_before(jiffies, uip_watchdog + 2*HZ/100)) | |
403fe5ae | 1198 | cpu_relax(); |
1da177e4 LT |
1199 | |
1200 | /* | |
1201 | * Only the values that we read from the RTC are set. We leave | |
b7599587 AC |
1202 | * tm_wday, tm_yday and tm_isdst untouched. Note that while the |
1203 | * RTC has RTC_DAY_OF_WEEK, we should usually ignore it, as it is | |
1204 | * only updated by the RTC when initially set to a non-zero value. | |
1da177e4 | 1205 | */ |
0f749646 | 1206 | spin_lock_irqsave(&rtc_lock, flags); |
1da177e4 LT |
1207 | rtc_tm->tm_sec = CMOS_READ(RTC_SECONDS); |
1208 | rtc_tm->tm_min = CMOS_READ(RTC_MINUTES); | |
1209 | rtc_tm->tm_hour = CMOS_READ(RTC_HOURS); | |
1210 | rtc_tm->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH); | |
1211 | rtc_tm->tm_mon = CMOS_READ(RTC_MONTH); | |
1212 | rtc_tm->tm_year = CMOS_READ(RTC_YEAR); | |
b7599587 AC |
1213 | /* Only set from 2.6.16 onwards */ |
1214 | rtc_tm->tm_wday = CMOS_READ(RTC_DAY_OF_WEEK); | |
1215 | ||
1da177e4 LT |
1216 | #ifdef CONFIG_MACH_DECSTATION |
1217 | real_year = CMOS_READ(RTC_DEC_YEAR); | |
1218 | #endif | |
1219 | ctrl = CMOS_READ(RTC_CONTROL); | |
0f749646 | 1220 | spin_unlock_irqrestore(&rtc_lock, flags); |
1da177e4 | 1221 | |
5fd1fe9c | 1222 | if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { |
357c6e63 AB |
1223 | rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec); |
1224 | rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min); | |
1225 | rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour); | |
1226 | rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday); | |
1227 | rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon); | |
1228 | rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year); | |
1229 | rtc_tm->tm_wday = bcd2bin(rtc_tm->tm_wday); | |
1da177e4 LT |
1230 | } |
1231 | ||
1232 | #ifdef CONFIG_MACH_DECSTATION | |
1233 | rtc_tm->tm_year += real_year - 72; | |
1234 | #endif | |
1235 | ||
1236 | /* | |
1237 | * Account for differences between how the RTC uses the values | |
1238 | * and how they are defined in a struct rtc_time; | |
1239 | */ | |
5fd1fe9c IM |
1240 | rtc_tm->tm_year += epoch - 1900; |
1241 | if (rtc_tm->tm_year <= 69) | |
1da177e4 LT |
1242 | rtc_tm->tm_year += 100; |
1243 | ||
1244 | rtc_tm->tm_mon--; | |
1245 | } | |
1246 | ||
1247 | static void get_rtc_alm_time(struct rtc_time *alm_tm) | |
1248 | { | |
1249 | unsigned char ctrl; | |
1250 | ||
1251 | /* | |
1252 | * Only the values that we read from the RTC are set. That | |
1253 | * means only tm_hour, tm_min, and tm_sec. | |
1254 | */ | |
1255 | spin_lock_irq(&rtc_lock); | |
1256 | alm_tm->tm_sec = CMOS_READ(RTC_SECONDS_ALARM); | |
1257 | alm_tm->tm_min = CMOS_READ(RTC_MINUTES_ALARM); | |
1258 | alm_tm->tm_hour = CMOS_READ(RTC_HOURS_ALARM); | |
1259 | ctrl = CMOS_READ(RTC_CONTROL); | |
1260 | spin_unlock_irq(&rtc_lock); | |
1261 | ||
5fd1fe9c | 1262 | if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { |
357c6e63 AB |
1263 | alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec); |
1264 | alm_tm->tm_min = bcd2bin(alm_tm->tm_min); | |
1265 | alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour); | |
1da177e4 LT |
1266 | } |
1267 | } | |
1268 | ||
1269 | #ifdef RTC_IRQ | |
1270 | /* | |
1271 | * Used to disable/enable interrupts for any one of UIE, AIE, PIE. | |
1272 | * Rumour has it that if you frob the interrupt enable/disable | |
1273 | * bits in RTC_CONTROL, you should read RTC_INTR_FLAGS, to | |
1274 | * ensure you actually start getting interrupts. Probably for | |
1275 | * compatibility with older/broken chipset RTC implementations. | |
1276 | * We also clear out any old irq data after an ioctl() that | |
1277 | * meddles with the interrupt enable/disable bits. | |
1278 | */ | |
1279 | ||
c3348760 | 1280 | static void mask_rtc_irq_bit_locked(unsigned char bit) |
1da177e4 LT |
1281 | { |
1282 | unsigned char val; | |
1283 | ||
c3348760 | 1284 | if (hpet_mask_rtc_irq_bit(bit)) |
1da177e4 | 1285 | return; |
1da177e4 LT |
1286 | val = CMOS_READ(RTC_CONTROL); |
1287 | val &= ~bit; | |
1288 | CMOS_WRITE(val, RTC_CONTROL); | |
1289 | CMOS_READ(RTC_INTR_FLAGS); | |
1290 | ||
1291 | rtc_irq_data = 0; | |
1da177e4 LT |
1292 | } |
1293 | ||
c3348760 | 1294 | static void set_rtc_irq_bit_locked(unsigned char bit) |
1da177e4 LT |
1295 | { |
1296 | unsigned char val; | |
1297 | ||
c3348760 | 1298 | if (hpet_set_rtc_irq_bit(bit)) |
1da177e4 | 1299 | return; |
1da177e4 LT |
1300 | val = CMOS_READ(RTC_CONTROL); |
1301 | val |= bit; | |
1302 | CMOS_WRITE(val, RTC_CONTROL); | |
1303 | CMOS_READ(RTC_INTR_FLAGS); | |
1304 | ||
1305 | rtc_irq_data = 0; | |
1da177e4 LT |
1306 | } |
1307 | #endif | |
1308 | ||
1309 | MODULE_AUTHOR("Paul Gortmaker"); | |
1310 | MODULE_LICENSE("GPL"); | |
1311 | MODULE_ALIAS_MISCDEV(RTC_MINOR); |