Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Real Time Clock interface for | |
3 | * - q40 and other m68k machines, | |
4 | * - HP PARISC machines | |
5 | * - PowerPC machines | |
6 | * emulate some RTC irq capabilities in software | |
7 | * | |
8 | * Copyright (C) 1999 Richard Zidlicky | |
9 | * | |
10 | * based on Paul Gortmaker's rtc.c device and | |
11 | * Sam Creasey Generic rtc driver | |
12 | * | |
13 | * This driver allows use of the real time clock (built into | |
14 | * nearly all computers) from user space. It exports the /dev/rtc | |
c685ce05 | 15 | * interface supporting various ioctl() and also the /proc/driver/rtc |
1da177e4 LT |
16 | * pseudo-file for status information. |
17 | * | |
18 | * The ioctls can be used to set the interrupt behaviour where | |
19 | * supported. | |
20 | * | |
21 | * The /dev/rtc interface will block on reads until an interrupt | |
22 | * has been received. If a RTC interrupt has already happened, | |
23 | * it will output an unsigned long and then block. The output value | |
24 | * contains the interrupt status in the low byte and the number of | |
25 | * interrupts since the last read in the remaining high bytes. The | |
26 | * /dev/rtc interface can also be used with the select(2) call. | |
27 | * | |
28 | * This program is free software; you can redistribute it and/or | |
29 | * modify it under the terms of the GNU General Public License | |
30 | * as published by the Free Software Foundation; either version | |
31 | * 2 of the License, or (at your option) any later version. | |
32 | * | |
33 | ||
34 | * 1.01 fix for 2.3.X rz@linux-m68k.org | |
35 | * 1.02 merged with code from genrtc.c rz@linux-m68k.org | |
36 | * 1.03 make it more portable zippel@linux-m68k.org | |
37 | * 1.04 removed useless timer code rz@linux-m68k.org | |
38 | * 1.05 portable RTC_UIE emulation rz@linux-m68k.org | |
39 | * 1.06 set_rtc_time can return an error trini@kernel.crashing.org | |
40 | * 1.07 ported to HP PARISC (hppa) Helge Deller <deller@gmx.de> | |
41 | */ | |
42 | ||
43 | #define RTC_VERSION "1.07" | |
44 | ||
45 | #include <linux/module.h> | |
86ae13b0 | 46 | #include <linux/sched.h> |
1da177e4 LT |
47 | #include <linux/errno.h> |
48 | #include <linux/miscdevice.h> | |
49 | #include <linux/fcntl.h> | |
50 | ||
51 | #include <linux/rtc.h> | |
52 | #include <linux/init.h> | |
53 | #include <linux/poll.h> | |
54 | #include <linux/proc_fs.h> | |
a6d935a5 | 55 | #include <linux/seq_file.h> |
613655fa | 56 | #include <linux/mutex.h> |
1da177e4 LT |
57 | #include <linux/workqueue.h> |
58 | ||
59 | #include <asm/uaccess.h> | |
1da177e4 LT |
60 | #include <asm/rtc.h> |
61 | ||
62 | /* | |
63 | * We sponge a minor off of the misc major. No need slurping | |
64 | * up another valuable major dev number for this. If you add | |
65 | * an ioctl, make sure you don't conflict with SPARC's RTC | |
66 | * ioctls. | |
67 | */ | |
68 | ||
613655fa | 69 | static DEFINE_MUTEX(gen_rtc_mutex); |
1da177e4 LT |
70 | static DECLARE_WAIT_QUEUE_HEAD(gen_rtc_wait); |
71 | ||
72 | /* | |
73 | * Bits in gen_rtc_status. | |
74 | */ | |
75 | ||
76 | #define RTC_IS_OPEN 0x01 /* means /dev/rtc is in use */ | |
77 | ||
78 | static unsigned char gen_rtc_status; /* bitmapped status byte. */ | |
79 | static unsigned long gen_rtc_irq_data; /* our output to the world */ | |
80 | ||
81 | /* months start at 0 now */ | |
82 | static unsigned char days_in_mo[] = | |
83 | {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; | |
84 | ||
85 | static int irq_active; | |
86 | ||
87 | #ifdef CONFIG_GEN_RTC_X | |
88 | static struct work_struct genrtc_task; | |
89 | static struct timer_list timer_task; | |
90 | ||
91 | static unsigned int oldsecs; | |
92 | static int lostint; | |
93 | static unsigned long tt_exp; | |
94 | ||
95 | static void gen_rtc_timer(unsigned long data); | |
96 | ||
97 | static volatile int stask_active; /* schedule_work */ | |
98 | static volatile int ttask_active; /* timer_task */ | |
99 | static int stop_rtc_timers; /* don't requeue tasks */ | |
100 | static DEFINE_SPINLOCK(gen_rtc_lock); | |
101 | ||
102 | static void gen_rtc_interrupt(unsigned long arg); | |
103 | ||
104 | /* | |
105 | * Routine to poll RTC seconds field for change as often as possible, | |
106 | * after first RTC_UIE use timer to reduce polling | |
107 | */ | |
c4028958 | 108 | static void genrtc_troutine(struct work_struct *work) |
1da177e4 LT |
109 | { |
110 | unsigned int tmp = get_rtc_ss(); | |
111 | ||
112 | if (stop_rtc_timers) { | |
113 | stask_active = 0; | |
114 | return; | |
115 | } | |
116 | ||
117 | if (oldsecs != tmp){ | |
118 | oldsecs = tmp; | |
119 | ||
120 | timer_task.function = gen_rtc_timer; | |
121 | timer_task.expires = jiffies + HZ - (HZ/10); | |
122 | tt_exp=timer_task.expires; | |
123 | ttask_active=1; | |
124 | stask_active=0; | |
125 | add_timer(&timer_task); | |
126 | ||
127 | gen_rtc_interrupt(0); | |
128 | } else if (schedule_work(&genrtc_task) == 0) | |
129 | stask_active = 0; | |
130 | } | |
131 | ||
132 | static void gen_rtc_timer(unsigned long data) | |
133 | { | |
134 | lostint = get_rtc_ss() - oldsecs ; | |
135 | if (lostint<0) | |
136 | lostint = 60 - lostint; | |
137 | if (time_after(jiffies, tt_exp)) | |
138 | printk(KERN_INFO "genrtc: timer task delayed by %ld jiffies\n", | |
139 | jiffies-tt_exp); | |
140 | ttask_active=0; | |
141 | stask_active=1; | |
142 | if ((schedule_work(&genrtc_task) == 0)) | |
143 | stask_active = 0; | |
144 | } | |
145 | ||
146 | /* | |
147 | * call gen_rtc_interrupt function to signal an RTC_UIE, | |
148 | * arg is unused. | |
149 | * Could be invoked either from a real interrupt handler or | |
150 | * from some routine that periodically (eg 100HZ) monitors | |
151 | * whether RTC_SECS changed | |
152 | */ | |
153 | static void gen_rtc_interrupt(unsigned long arg) | |
154 | { | |
155 | /* We store the status in the low byte and the number of | |
156 | * interrupts received since the last read in the remainder | |
157 | * of rtc_irq_data. */ | |
158 | ||
159 | gen_rtc_irq_data += 0x100; | |
160 | gen_rtc_irq_data &= ~0xff; | |
161 | gen_rtc_irq_data |= RTC_UIE; | |
162 | ||
163 | if (lostint){ | |
164 | printk("genrtc: system delaying clock ticks?\n"); | |
165 | /* increment count so that userspace knows something is wrong */ | |
166 | gen_rtc_irq_data += ((lostint-1)<<8); | |
167 | lostint = 0; | |
168 | } | |
169 | ||
170 | wake_up_interruptible(&gen_rtc_wait); | |
171 | } | |
172 | ||
173 | /* | |
174 | * Now all the various file operations that we export. | |
175 | */ | |
176 | static ssize_t gen_rtc_read(struct file *file, char __user *buf, | |
177 | size_t count, loff_t *ppos) | |
178 | { | |
1da177e4 LT |
179 | unsigned long data; |
180 | ssize_t retval; | |
181 | ||
182 | if (count != sizeof (unsigned int) && count != sizeof (unsigned long)) | |
183 | return -EINVAL; | |
184 | ||
185 | if (file->f_flags & O_NONBLOCK && !gen_rtc_irq_data) | |
186 | return -EAGAIN; | |
187 | ||
e0955e14 JS |
188 | retval = wait_event_interruptible(gen_rtc_wait, |
189 | (data = xchg(&gen_rtc_irq_data, 0))); | |
190 | if (retval) | |
191 | goto out; | |
1da177e4 LT |
192 | |
193 | /* first test allows optimizer to nuke this case for 32-bit machines */ | |
194 | if (sizeof (int) != sizeof (long) && count == sizeof (unsigned int)) { | |
195 | unsigned int uidata = data; | |
f3537ea7 AN |
196 | retval = put_user(uidata, (unsigned int __user *)buf) ?: |
197 | sizeof(unsigned int); | |
1da177e4 LT |
198 | } |
199 | else { | |
f3537ea7 AN |
200 | retval = put_user(data, (unsigned long __user *)buf) ?: |
201 | sizeof(unsigned long); | |
1da177e4 | 202 | } |
e0955e14 | 203 | out: |
1da177e4 LT |
204 | return retval; |
205 | } | |
206 | ||
207 | static unsigned int gen_rtc_poll(struct file *file, | |
208 | struct poll_table_struct *wait) | |
209 | { | |
210 | poll_wait(file, &gen_rtc_wait, wait); | |
211 | if (gen_rtc_irq_data != 0) | |
212 | return POLLIN | POLLRDNORM; | |
213 | return 0; | |
214 | } | |
215 | ||
216 | #endif | |
217 | ||
218 | /* | |
219 | * Used to disable/enable interrupts, only RTC_UIE supported | |
220 | * We also clear out any old irq data after an ioctl() that | |
221 | * meddles with the interrupt enable/disable bits. | |
222 | */ | |
223 | ||
224 | static inline void gen_clear_rtc_irq_bit(unsigned char bit) | |
225 | { | |
226 | #ifdef CONFIG_GEN_RTC_X | |
227 | stop_rtc_timers = 1; | |
228 | if (ttask_active){ | |
229 | del_timer_sync(&timer_task); | |
230 | ttask_active = 0; | |
231 | } | |
232 | while (stask_active) | |
233 | schedule(); | |
234 | ||
235 | spin_lock(&gen_rtc_lock); | |
236 | irq_active = 0; | |
237 | spin_unlock(&gen_rtc_lock); | |
238 | #endif | |
239 | } | |
240 | ||
241 | static inline int gen_set_rtc_irq_bit(unsigned char bit) | |
242 | { | |
243 | #ifdef CONFIG_GEN_RTC_X | |
244 | spin_lock(&gen_rtc_lock); | |
245 | if ( !irq_active ) { | |
246 | irq_active = 1; | |
247 | stop_rtc_timers = 0; | |
248 | lostint = 0; | |
c4028958 | 249 | INIT_WORK(&genrtc_task, genrtc_troutine); |
1da177e4 LT |
250 | oldsecs = get_rtc_ss(); |
251 | init_timer(&timer_task); | |
252 | ||
253 | stask_active = 1; | |
254 | if (schedule_work(&genrtc_task) == 0){ | |
255 | stask_active = 0; | |
256 | } | |
257 | } | |
258 | spin_unlock(&gen_rtc_lock); | |
259 | gen_rtc_irq_data = 0; | |
260 | return 0; | |
261 | #else | |
262 | return -EINVAL; | |
263 | #endif | |
264 | } | |
265 | ||
55929332 | 266 | static int gen_rtc_ioctl(struct file *file, |
1da177e4 LT |
267 | unsigned int cmd, unsigned long arg) |
268 | { | |
269 | struct rtc_time wtime; | |
270 | struct rtc_pll_info pll; | |
271 | void __user *argp = (void __user *)arg; | |
272 | ||
273 | switch (cmd) { | |
274 | ||
275 | case RTC_PLL_GET: | |
276 | if (get_rtc_pll(&pll)) | |
277 | return -EINVAL; | |
278 | else | |
279 | return copy_to_user(argp, &pll, sizeof pll) ? -EFAULT : 0; | |
280 | ||
281 | case RTC_PLL_SET: | |
282 | if (!capable(CAP_SYS_TIME)) | |
283 | return -EACCES; | |
284 | if (copy_from_user(&pll, argp, sizeof(pll))) | |
285 | return -EFAULT; | |
286 | return set_rtc_pll(&pll); | |
287 | ||
288 | case RTC_UIE_OFF: /* disable ints from RTC updates. */ | |
289 | gen_clear_rtc_irq_bit(RTC_UIE); | |
290 | return 0; | |
291 | ||
292 | case RTC_UIE_ON: /* enable ints for RTC updates. */ | |
293 | return gen_set_rtc_irq_bit(RTC_UIE); | |
294 | ||
295 | case RTC_RD_TIME: /* Read the time/date from RTC */ | |
296 | /* this doesn't get week-day, who cares */ | |
297 | memset(&wtime, 0, sizeof(wtime)); | |
298 | get_rtc_time(&wtime); | |
299 | ||
300 | return copy_to_user(argp, &wtime, sizeof(wtime)) ? -EFAULT : 0; | |
301 | ||
302 | case RTC_SET_TIME: /* Set the RTC */ | |
303 | { | |
304 | int year; | |
305 | unsigned char leap_yr; | |
306 | ||
307 | if (!capable(CAP_SYS_TIME)) | |
308 | return -EACCES; | |
309 | ||
310 | if (copy_from_user(&wtime, argp, sizeof(wtime))) | |
311 | return -EFAULT; | |
312 | ||
313 | year = wtime.tm_year + 1900; | |
314 | leap_yr = ((!(year % 4) && (year % 100)) || | |
315 | !(year % 400)); | |
316 | ||
317 | if ((wtime.tm_mon < 0 || wtime.tm_mon > 11) || (wtime.tm_mday < 1)) | |
318 | return -EINVAL; | |
319 | ||
320 | if (wtime.tm_mday < 0 || wtime.tm_mday > | |
321 | (days_in_mo[wtime.tm_mon] + ((wtime.tm_mon == 1) && leap_yr))) | |
322 | return -EINVAL; | |
323 | ||
324 | if (wtime.tm_hour < 0 || wtime.tm_hour >= 24 || | |
325 | wtime.tm_min < 0 || wtime.tm_min >= 60 || | |
326 | wtime.tm_sec < 0 || wtime.tm_sec >= 60) | |
327 | return -EINVAL; | |
328 | ||
329 | return set_rtc_time(&wtime); | |
330 | } | |
331 | } | |
332 | ||
333 | return -EINVAL; | |
334 | } | |
335 | ||
55929332 AB |
336 | static long gen_rtc_unlocked_ioctl(struct file *file, unsigned int cmd, |
337 | unsigned long arg) | |
338 | { | |
339 | int ret; | |
340 | ||
613655fa | 341 | mutex_lock(&gen_rtc_mutex); |
55929332 | 342 | ret = gen_rtc_ioctl(file, cmd, arg); |
613655fa | 343 | mutex_unlock(&gen_rtc_mutex); |
55929332 AB |
344 | |
345 | return ret; | |
346 | } | |
347 | ||
1da177e4 LT |
348 | /* |
349 | * We enforce only one user at a time here with the open/close. | |
350 | * Also clear the previous interrupt data on an open, and clean | |
351 | * up things on a close. | |
352 | */ | |
353 | ||
354 | static int gen_rtc_open(struct inode *inode, struct file *file) | |
355 | { | |
613655fa | 356 | mutex_lock(&gen_rtc_mutex); |
742a2fe3 | 357 | if (gen_rtc_status & RTC_IS_OPEN) { |
613655fa | 358 | mutex_unlock(&gen_rtc_mutex); |
1da177e4 | 359 | return -EBUSY; |
742a2fe3 | 360 | } |
1da177e4 LT |
361 | |
362 | gen_rtc_status |= RTC_IS_OPEN; | |
363 | gen_rtc_irq_data = 0; | |
364 | irq_active = 0; | |
613655fa | 365 | mutex_unlock(&gen_rtc_mutex); |
1da177e4 LT |
366 | |
367 | return 0; | |
368 | } | |
369 | ||
370 | static int gen_rtc_release(struct inode *inode, struct file *file) | |
371 | { | |
372 | /* | |
373 | * Turn off all interrupts once the device is no longer | |
374 | * in use and clear the data. | |
375 | */ | |
376 | ||
377 | gen_clear_rtc_irq_bit(RTC_PIE|RTC_AIE|RTC_UIE); | |
378 | ||
379 | gen_rtc_status &= ~RTC_IS_OPEN; | |
380 | return 0; | |
381 | } | |
382 | ||
383 | ||
384 | #ifdef CONFIG_PROC_FS | |
385 | ||
386 | /* | |
c685ce05 | 387 | * Info exported via "/proc/driver/rtc". |
1da177e4 LT |
388 | */ |
389 | ||
a6d935a5 | 390 | static int gen_rtc_proc_show(struct seq_file *m, void *v) |
1da177e4 | 391 | { |
1da177e4 LT |
392 | struct rtc_time tm; |
393 | unsigned int flags; | |
394 | struct rtc_pll_info pll; | |
395 | ||
1da177e4 LT |
396 | flags = get_rtc_time(&tm); |
397 | ||
a6d935a5 | 398 | seq_printf(m, |
1da177e4 LT |
399 | "rtc_time\t: %02d:%02d:%02d\n" |
400 | "rtc_date\t: %04d-%02d-%02d\n" | |
401 | "rtc_epoch\t: %04u\n", | |
402 | tm.tm_hour, tm.tm_min, tm.tm_sec, | |
403 | tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 1900); | |
404 | ||
405 | tm.tm_hour = tm.tm_min = tm.tm_sec = 0; | |
406 | ||
a6d935a5 | 407 | seq_puts(m, "alarm\t\t: "); |
1da177e4 | 408 | if (tm.tm_hour <= 24) |
a6d935a5 | 409 | seq_printf(m, "%02d:", tm.tm_hour); |
1da177e4 | 410 | else |
a6d935a5 | 411 | seq_puts(m, "**:"); |
1da177e4 LT |
412 | |
413 | if (tm.tm_min <= 59) | |
a6d935a5 | 414 | seq_printf(m, "%02d:", tm.tm_min); |
1da177e4 | 415 | else |
a6d935a5 | 416 | seq_puts(m, "**:"); |
1da177e4 LT |
417 | |
418 | if (tm.tm_sec <= 59) | |
a6d935a5 | 419 | seq_printf(m, "%02d\n", tm.tm_sec); |
1da177e4 | 420 | else |
a6d935a5 | 421 | seq_puts(m, "**\n"); |
1da177e4 | 422 | |
a6d935a5 | 423 | seq_printf(m, |
1da177e4 LT |
424 | "DST_enable\t: %s\n" |
425 | "BCD\t\t: %s\n" | |
426 | "24hr\t\t: %s\n" | |
427 | "square_wave\t: %s\n" | |
428 | "alarm_IRQ\t: %s\n" | |
429 | "update_IRQ\t: %s\n" | |
430 | "periodic_IRQ\t: %s\n" | |
431 | "periodic_freq\t: %ld\n" | |
432 | "batt_status\t: %s\n", | |
433 | (flags & RTC_DST_EN) ? "yes" : "no", | |
434 | (flags & RTC_DM_BINARY) ? "no" : "yes", | |
435 | (flags & RTC_24H) ? "yes" : "no", | |
436 | (flags & RTC_SQWE) ? "yes" : "no", | |
437 | (flags & RTC_AIE) ? "yes" : "no", | |
438 | irq_active ? "yes" : "no", | |
439 | (flags & RTC_PIE) ? "yes" : "no", | |
440 | 0L /* freq */, | |
441 | (flags & RTC_BATT_BAD) ? "bad" : "okay"); | |
442 | if (!get_rtc_pll(&pll)) | |
a6d935a5 | 443 | seq_printf(m, |
1da177e4 LT |
444 | "PLL adjustment\t: %d\n" |
445 | "PLL max +ve adjustment\t: %d\n" | |
446 | "PLL max -ve adjustment\t: %d\n" | |
447 | "PLL +ve adjustment factor\t: %d\n" | |
448 | "PLL -ve adjustment factor\t: %d\n" | |
449 | "PLL frequency\t: %ld\n", | |
450 | pll.pll_value, | |
451 | pll.pll_max, | |
452 | pll.pll_min, | |
453 | pll.pll_posmult, | |
454 | pll.pll_negmult, | |
455 | pll.pll_clock); | |
a6d935a5 | 456 | return 0; |
1da177e4 LT |
457 | } |
458 | ||
a6d935a5 | 459 | static int gen_rtc_proc_open(struct inode *inode, struct file *file) |
1da177e4 | 460 | { |
a6d935a5 | 461 | return single_open(file, gen_rtc_proc_show, NULL); |
1da177e4 LT |
462 | } |
463 | ||
a6d935a5 DH |
464 | static const struct file_operations gen_rtc_proc_fops = { |
465 | .open = gen_rtc_proc_open, | |
466 | .read = seq_read, | |
467 | .llseek = seq_lseek, | |
2e7718cf | 468 | .release = single_release, |
a6d935a5 DH |
469 | }; |
470 | ||
1da177e4 LT |
471 | static int __init gen_rtc_proc_init(void) |
472 | { | |
473 | struct proc_dir_entry *r; | |
474 | ||
a6d935a5 | 475 | r = proc_create("driver/rtc", 0, NULL, &gen_rtc_proc_fops); |
1da177e4 LT |
476 | if (!r) |
477 | return -ENOMEM; | |
478 | return 0; | |
479 | } | |
480 | #else | |
481 | static inline int gen_rtc_proc_init(void) { return 0; } | |
482 | #endif /* CONFIG_PROC_FS */ | |
483 | ||
484 | ||
485 | /* | |
486 | * The various file operations we support. | |
487 | */ | |
488 | ||
62322d25 | 489 | static const struct file_operations gen_rtc_fops = { |
1da177e4 LT |
490 | .owner = THIS_MODULE, |
491 | #ifdef CONFIG_GEN_RTC_X | |
492 | .read = gen_rtc_read, | |
493 | .poll = gen_rtc_poll, | |
494 | #endif | |
55929332 | 495 | .unlocked_ioctl = gen_rtc_unlocked_ioctl, |
1da177e4 LT |
496 | .open = gen_rtc_open, |
497 | .release = gen_rtc_release, | |
6038f373 | 498 | .llseek = noop_llseek, |
1da177e4 LT |
499 | }; |
500 | ||
501 | static struct miscdevice rtc_gen_dev = | |
502 | { | |
503 | .minor = RTC_MINOR, | |
504 | .name = "rtc", | |
505 | .fops = &gen_rtc_fops, | |
506 | }; | |
507 | ||
508 | static int __init rtc_generic_init(void) | |
509 | { | |
510 | int retval; | |
511 | ||
512 | printk(KERN_INFO "Generic RTC Driver v%s\n", RTC_VERSION); | |
513 | ||
514 | retval = misc_register(&rtc_gen_dev); | |
515 | if (retval < 0) | |
516 | return retval; | |
517 | ||
518 | retval = gen_rtc_proc_init(); | |
519 | if (retval) { | |
520 | misc_deregister(&rtc_gen_dev); | |
521 | return retval; | |
522 | } | |
523 | ||
524 | return 0; | |
525 | } | |
526 | ||
527 | static void __exit rtc_generic_exit(void) | |
528 | { | |
529 | remove_proc_entry ("driver/rtc", NULL); | |
530 | misc_deregister(&rtc_gen_dev); | |
531 | } | |
532 | ||
533 | ||
534 | module_init(rtc_generic_init); | |
535 | module_exit(rtc_generic_exit); | |
536 | ||
537 | MODULE_AUTHOR("Richard Zidlicky"); | |
538 | MODULE_LICENSE("GPL"); | |
539 | MODULE_ALIAS_MISCDEV(RTC_MINOR); |