xref: /openbmc/linux/drivers/acpi/proc.c (revision b04b4f78)
1 #include <linux/proc_fs.h>
2 #include <linux/seq_file.h>
3 #include <linux/suspend.h>
4 #include <linux/bcd.h>
5 #include <asm/uaccess.h>
6 
7 #include <acpi/acpi_bus.h>
8 #include <acpi/acpi_drivers.h>
9 
10 #ifdef CONFIG_X86
11 #include <linux/mc146818rtc.h>
12 #endif
13 
14 #include "sleep.h"
15 
16 #define _COMPONENT		ACPI_SYSTEM_COMPONENT
17 
18 /*
19  * this file provides support for:
20  * /proc/acpi/sleep
21  * /proc/acpi/alarm
22  * /proc/acpi/wakeup
23  */
24 
25 ACPI_MODULE_NAME("sleep")
26 #ifdef	CONFIG_ACPI_PROCFS
27 static int acpi_system_sleep_seq_show(struct seq_file *seq, void *offset)
28 {
29 	int i;
30 
31 	for (i = 0; i <= ACPI_STATE_S5; i++) {
32 		if (sleep_states[i]) {
33 			seq_printf(seq, "S%d ", i);
34 		}
35 	}
36 
37 	seq_puts(seq, "\n");
38 
39 	return 0;
40 }
41 
42 static int acpi_system_sleep_open_fs(struct inode *inode, struct file *file)
43 {
44 	return single_open(file, acpi_system_sleep_seq_show, PDE(inode)->data);
45 }
46 
47 static ssize_t
48 acpi_system_write_sleep(struct file *file,
49 			const char __user * buffer, size_t count, loff_t * ppos)
50 {
51 	char str[12];
52 	u32 state = 0;
53 	int error = 0;
54 
55 	if (count > sizeof(str) - 1)
56 		goto Done;
57 	memset(str, 0, sizeof(str));
58 	if (copy_from_user(str, buffer, count))
59 		return -EFAULT;
60 
61 	/* Check for S4 bios request */
62 	if (!strcmp(str, "4b")) {
63 		error = acpi_suspend(4);
64 		goto Done;
65 	}
66 	state = simple_strtoul(str, NULL, 0);
67 #ifdef CONFIG_HIBERNATION
68 	if (state == 4) {
69 		error = hibernate();
70 		goto Done;
71 	}
72 #endif
73 	error = acpi_suspend(state);
74       Done:
75 	return error ? error : count;
76 }
77 #endif				/* CONFIG_ACPI_PROCFS */
78 
79 #if defined(CONFIG_RTC_DRV_CMOS) || defined(CONFIG_RTC_DRV_CMOS_MODULE) || !defined(CONFIG_X86)
80 /* use /sys/class/rtc/rtcX/wakealarm instead; it's not ACPI-specific */
81 #else
82 #define	HAVE_ACPI_LEGACY_ALARM
83 #endif
84 
85 #ifdef	HAVE_ACPI_LEGACY_ALARM
86 
87 static u32 cmos_bcd_read(int offset, int rtc_control);
88 
89 static int acpi_system_alarm_seq_show(struct seq_file *seq, void *offset)
90 {
91 	u32 sec, min, hr;
92 	u32 day, mo, yr, cent = 0;
93 	u32 today = 0;
94 	unsigned char rtc_control = 0;
95 	unsigned long flags;
96 
97 	spin_lock_irqsave(&rtc_lock, flags);
98 
99 	rtc_control = CMOS_READ(RTC_CONTROL);
100 	sec = cmos_bcd_read(RTC_SECONDS_ALARM, rtc_control);
101 	min = cmos_bcd_read(RTC_MINUTES_ALARM, rtc_control);
102 	hr = cmos_bcd_read(RTC_HOURS_ALARM, rtc_control);
103 
104 	/* If we ever get an FACP with proper values... */
105 	if (acpi_gbl_FADT.day_alarm) {
106 		/* ACPI spec: only low 6 its should be cared */
107 		day = CMOS_READ(acpi_gbl_FADT.day_alarm) & 0x3F;
108 		if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
109 			day = bcd2bin(day);
110 	} else
111 		day = cmos_bcd_read(RTC_DAY_OF_MONTH, rtc_control);
112 	if (acpi_gbl_FADT.month_alarm)
113 		mo = cmos_bcd_read(acpi_gbl_FADT.month_alarm, rtc_control);
114 	else {
115 		mo = cmos_bcd_read(RTC_MONTH, rtc_control);
116 		today = cmos_bcd_read(RTC_DAY_OF_MONTH, rtc_control);
117 	}
118 	if (acpi_gbl_FADT.century)
119 		cent = cmos_bcd_read(acpi_gbl_FADT.century, rtc_control);
120 
121 	yr = cmos_bcd_read(RTC_YEAR, rtc_control);
122 
123 	spin_unlock_irqrestore(&rtc_lock, flags);
124 
125 	/* we're trusting the FADT (see above) */
126 	if (!acpi_gbl_FADT.century)
127 		/* If we're not trusting the FADT, we should at least make it
128 		 * right for _this_ century... ehm, what is _this_ century?
129 		 *
130 		 * TBD:
131 		 *  ASAP: find piece of code in the kernel, e.g. star tracker driver,
132 		 *        which we can trust to determine the century correctly. Atom
133 		 *        watch driver would be nice, too...
134 		 *
135 		 *  if that has not happened, change for first release in 2050:
136 		 *        if (yr<50)
137 		 *                yr += 2100;
138 		 *        else
139 		 *                yr += 2000;   // current line of code
140 		 *
141 		 *  if that has not happened either, please do on 2099/12/31:23:59:59
142 		 *        s/2000/2100
143 		 *
144 		 */
145 		yr += 2000;
146 	else
147 		yr += cent * 100;
148 
149 	/*
150 	 * Show correct dates for alarms up to a month into the future.
151 	 * This solves issues for nearly all situations with the common
152 	 * 30-day alarm clocks in PC hardware.
153 	 */
154 	if (day < today) {
155 		if (mo < 12) {
156 			mo += 1;
157 		} else {
158 			mo = 1;
159 			yr += 1;
160 		}
161 	}
162 
163 	seq_printf(seq, "%4.4u-", yr);
164 	(mo > 12) ? seq_puts(seq, "**-") : seq_printf(seq, "%2.2u-", mo);
165 	(day > 31) ? seq_puts(seq, "** ") : seq_printf(seq, "%2.2u ", day);
166 	(hr > 23) ? seq_puts(seq, "**:") : seq_printf(seq, "%2.2u:", hr);
167 	(min > 59) ? seq_puts(seq, "**:") : seq_printf(seq, "%2.2u:", min);
168 	(sec > 59) ? seq_puts(seq, "**\n") : seq_printf(seq, "%2.2u\n", sec);
169 
170 	return 0;
171 }
172 
173 static int acpi_system_alarm_open_fs(struct inode *inode, struct file *file)
174 {
175 	return single_open(file, acpi_system_alarm_seq_show, PDE(inode)->data);
176 }
177 
178 static int get_date_field(char **p, u32 * value)
179 {
180 	char *next = NULL;
181 	char *string_end = NULL;
182 	int result = -EINVAL;
183 
184 	/*
185 	 * Try to find delimeter, only to insert null.  The end of the
186 	 * string won't have one, but is still valid.
187 	 */
188 	if (*p == NULL)
189 		return result;
190 
191 	next = strpbrk(*p, "- :");
192 	if (next)
193 		*next++ = '\0';
194 
195 	*value = simple_strtoul(*p, &string_end, 10);
196 
197 	/* Signal success if we got a good digit */
198 	if (string_end != *p)
199 		result = 0;
200 
201 	if (next)
202 		*p = next;
203 	else
204 		*p = NULL;
205 
206 	return result;
207 }
208 
209 /* Read a possibly BCD register, always return binary */
210 static u32 cmos_bcd_read(int offset, int rtc_control)
211 {
212 	u32 val = CMOS_READ(offset);
213 	if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
214 		val = bcd2bin(val);
215 	return val;
216 }
217 
218 /* Write binary value into possibly BCD register */
219 static void cmos_bcd_write(u32 val, int offset, int rtc_control)
220 {
221 	if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
222 		val = bin2bcd(val);
223 	CMOS_WRITE(val, offset);
224 }
225 
226 static ssize_t
227 acpi_system_write_alarm(struct file *file,
228 			const char __user * buffer, size_t count, loff_t * ppos)
229 {
230 	int result = 0;
231 	char alarm_string[30] = { '\0' };
232 	char *p = alarm_string;
233 	u32 sec, min, hr, day, mo, yr;
234 	int adjust = 0;
235 	unsigned char rtc_control = 0;
236 
237 	if (count > sizeof(alarm_string) - 1)
238 		return -EINVAL;
239 
240 	if (copy_from_user(alarm_string, buffer, count))
241 		return -EFAULT;
242 
243 	alarm_string[count] = '\0';
244 
245 	/* check for time adjustment */
246 	if (alarm_string[0] == '+') {
247 		p++;
248 		adjust = 1;
249 	}
250 
251 	if ((result = get_date_field(&p, &yr)))
252 		goto end;
253 	if ((result = get_date_field(&p, &mo)))
254 		goto end;
255 	if ((result = get_date_field(&p, &day)))
256 		goto end;
257 	if ((result = get_date_field(&p, &hr)))
258 		goto end;
259 	if ((result = get_date_field(&p, &min)))
260 		goto end;
261 	if ((result = get_date_field(&p, &sec)))
262 		goto end;
263 
264 	spin_lock_irq(&rtc_lock);
265 
266 	rtc_control = CMOS_READ(RTC_CONTROL);
267 
268 	if (adjust) {
269 		yr += cmos_bcd_read(RTC_YEAR, rtc_control);
270 		mo += cmos_bcd_read(RTC_MONTH, rtc_control);
271 		day += cmos_bcd_read(RTC_DAY_OF_MONTH, rtc_control);
272 		hr += cmos_bcd_read(RTC_HOURS, rtc_control);
273 		min += cmos_bcd_read(RTC_MINUTES, rtc_control);
274 		sec += cmos_bcd_read(RTC_SECONDS, rtc_control);
275 	}
276 
277 	spin_unlock_irq(&rtc_lock);
278 
279 	if (sec > 59) {
280 		min += sec/60;
281 		sec = sec%60;
282 	}
283 	if (min > 59) {
284 		hr += min/60;
285 		min = min%60;
286 	}
287 	if (hr > 23) {
288 		day += hr/24;
289 		hr = hr%24;
290 	}
291 	if (day > 31) {
292 		mo += day/32;
293 		day = day%32;
294 	}
295 	if (mo > 12) {
296 		yr += mo/13;
297 		mo = mo%13;
298 	}
299 
300 	spin_lock_irq(&rtc_lock);
301 	/*
302 	 * Disable alarm interrupt before setting alarm timer or else
303 	 * when ACPI_EVENT_RTC is enabled, a spurious ACPI interrupt occurs
304 	 */
305 	rtc_control &= ~RTC_AIE;
306 	CMOS_WRITE(rtc_control, RTC_CONTROL);
307 	CMOS_READ(RTC_INTR_FLAGS);
308 
309 	/* write the fields the rtc knows about */
310 	cmos_bcd_write(hr, RTC_HOURS_ALARM, rtc_control);
311 	cmos_bcd_write(min, RTC_MINUTES_ALARM, rtc_control);
312 	cmos_bcd_write(sec, RTC_SECONDS_ALARM, rtc_control);
313 
314 	/*
315 	 * If the system supports an enhanced alarm it will have non-zero
316 	 * offsets into the CMOS RAM here -- which for some reason are pointing
317 	 * to the RTC area of memory.
318 	 */
319 	if (acpi_gbl_FADT.day_alarm)
320 		cmos_bcd_write(day, acpi_gbl_FADT.day_alarm, rtc_control);
321 	if (acpi_gbl_FADT.month_alarm)
322 		cmos_bcd_write(mo, acpi_gbl_FADT.month_alarm, rtc_control);
323 	if (acpi_gbl_FADT.century) {
324 		if (adjust)
325 			yr += cmos_bcd_read(acpi_gbl_FADT.century, rtc_control) * 100;
326 		cmos_bcd_write(yr / 100, acpi_gbl_FADT.century, rtc_control);
327 	}
328 	/* enable the rtc alarm interrupt */
329 	rtc_control |= RTC_AIE;
330 	CMOS_WRITE(rtc_control, RTC_CONTROL);
331 	CMOS_READ(RTC_INTR_FLAGS);
332 
333 	spin_unlock_irq(&rtc_lock);
334 
335 	acpi_clear_event(ACPI_EVENT_RTC);
336 	acpi_enable_event(ACPI_EVENT_RTC, 0);
337 
338 	*ppos += count;
339 
340 	result = 0;
341       end:
342 	return result ? result : count;
343 }
344 #endif				/* HAVE_ACPI_LEGACY_ALARM */
345 
346 static int
347 acpi_system_wakeup_device_seq_show(struct seq_file *seq, void *offset)
348 {
349 	struct list_head *node, *next;
350 
351 	seq_printf(seq, "Device\tS-state\t  Status   Sysfs node\n");
352 
353 	mutex_lock(&acpi_device_lock);
354 	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
355 		struct acpi_device *dev =
356 		    container_of(node, struct acpi_device, wakeup_list);
357 		struct device *ldev;
358 
359 		if (!dev->wakeup.flags.valid)
360 			continue;
361 
362 		ldev = acpi_get_physical_device(dev->handle);
363 		seq_printf(seq, "%s\t  S%d\t%c%-8s  ",
364 			   dev->pnp.bus_id,
365 			   (u32) dev->wakeup.sleep_state,
366 			   dev->wakeup.flags.run_wake ? '*' : ' ',
367 			   dev->wakeup.state.enabled ? "enabled" : "disabled");
368 		if (ldev)
369 			seq_printf(seq, "%s:%s",
370 				   ldev->bus ? ldev->bus->name : "no-bus",
371 				   dev_name(ldev));
372 		seq_printf(seq, "\n");
373 		put_device(ldev);
374 
375 	}
376 	mutex_unlock(&acpi_device_lock);
377 	return 0;
378 }
379 
380 static void physical_device_enable_wakeup(struct acpi_device *adev)
381 {
382 	struct device *dev = acpi_get_physical_device(adev->handle);
383 
384 	if (dev && device_can_wakeup(dev))
385 		device_set_wakeup_enable(dev, adev->wakeup.state.enabled);
386 }
387 
388 static ssize_t
389 acpi_system_write_wakeup_device(struct file *file,
390 				const char __user * buffer,
391 				size_t count, loff_t * ppos)
392 {
393 	struct list_head *node, *next;
394 	char strbuf[5];
395 	char str[5] = "";
396 	int len = count;
397 	struct acpi_device *found_dev = NULL;
398 
399 	if (len > 4)
400 		len = 4;
401 
402 	if (copy_from_user(strbuf, buffer, len))
403 		return -EFAULT;
404 	strbuf[len] = '\0';
405 	sscanf(strbuf, "%s", str);
406 
407 	mutex_lock(&acpi_device_lock);
408 	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
409 		struct acpi_device *dev =
410 		    container_of(node, struct acpi_device, wakeup_list);
411 		if (!dev->wakeup.flags.valid)
412 			continue;
413 
414 		if (!strncmp(dev->pnp.bus_id, str, 4)) {
415 			dev->wakeup.state.enabled =
416 			    dev->wakeup.state.enabled ? 0 : 1;
417 			found_dev = dev;
418 			break;
419 		}
420 	}
421 	if (found_dev) {
422 		physical_device_enable_wakeup(found_dev);
423 		list_for_each_safe(node, next, &acpi_wakeup_device_list) {
424 			struct acpi_device *dev = container_of(node,
425 							       struct
426 							       acpi_device,
427 							       wakeup_list);
428 
429 			if ((dev != found_dev) &&
430 			    (dev->wakeup.gpe_number ==
431 			     found_dev->wakeup.gpe_number)
432 			    && (dev->wakeup.gpe_device ==
433 				found_dev->wakeup.gpe_device)) {
434 				printk(KERN_WARNING
435 				       "ACPI: '%s' and '%s' have the same GPE, "
436 				       "can't disable/enable one seperately\n",
437 				       dev->pnp.bus_id, found_dev->pnp.bus_id);
438 				dev->wakeup.state.enabled =
439 				    found_dev->wakeup.state.enabled;
440 				physical_device_enable_wakeup(dev);
441 			}
442 		}
443 	}
444 	mutex_unlock(&acpi_device_lock);
445 	return count;
446 }
447 
448 static int
449 acpi_system_wakeup_device_open_fs(struct inode *inode, struct file *file)
450 {
451 	return single_open(file, acpi_system_wakeup_device_seq_show,
452 			   PDE(inode)->data);
453 }
454 
455 static const struct file_operations acpi_system_wakeup_device_fops = {
456 	.owner = THIS_MODULE,
457 	.open = acpi_system_wakeup_device_open_fs,
458 	.read = seq_read,
459 	.write = acpi_system_write_wakeup_device,
460 	.llseek = seq_lseek,
461 	.release = single_release,
462 };
463 
464 #ifdef	CONFIG_ACPI_PROCFS
465 static const struct file_operations acpi_system_sleep_fops = {
466 	.owner = THIS_MODULE,
467 	.open = acpi_system_sleep_open_fs,
468 	.read = seq_read,
469 	.write = acpi_system_write_sleep,
470 	.llseek = seq_lseek,
471 	.release = single_release,
472 };
473 #endif				/* CONFIG_ACPI_PROCFS */
474 
475 #ifdef	HAVE_ACPI_LEGACY_ALARM
476 static const struct file_operations acpi_system_alarm_fops = {
477 	.owner = THIS_MODULE,
478 	.open = acpi_system_alarm_open_fs,
479 	.read = seq_read,
480 	.write = acpi_system_write_alarm,
481 	.llseek = seq_lseek,
482 	.release = single_release,
483 };
484 
485 static u32 rtc_handler(void *context)
486 {
487 	acpi_clear_event(ACPI_EVENT_RTC);
488 	acpi_disable_event(ACPI_EVENT_RTC, 0);
489 
490 	return ACPI_INTERRUPT_HANDLED;
491 }
492 #endif				/* HAVE_ACPI_LEGACY_ALARM */
493 
494 int __init acpi_sleep_proc_init(void)
495 {
496 #ifdef	CONFIG_ACPI_PROCFS
497 	/* 'sleep' [R/W] */
498 	proc_create("sleep", S_IFREG | S_IRUGO | S_IWUSR,
499 		    acpi_root_dir, &acpi_system_sleep_fops);
500 #endif				/* CONFIG_ACPI_PROCFS */
501 
502 #ifdef	HAVE_ACPI_LEGACY_ALARM
503 	/* 'alarm' [R/W] */
504 	proc_create("alarm", S_IFREG | S_IRUGO | S_IWUSR,
505 		    acpi_root_dir, &acpi_system_alarm_fops);
506 
507 	acpi_install_fixed_event_handler(ACPI_EVENT_RTC, rtc_handler, NULL);
508 	/*
509 	 * Disable the RTC event after installing RTC handler.
510 	 * Only when RTC alarm is set will it be enabled.
511 	 */
512 	acpi_clear_event(ACPI_EVENT_RTC);
513 	acpi_disable_event(ACPI_EVENT_RTC, 0);
514 #endif				/* HAVE_ACPI_LEGACY_ALARM */
515 
516 	/* 'wakeup device' [R/W] */
517 	proc_create("wakeup", S_IFREG | S_IRUGO | S_IWUSR,
518 		    acpi_root_dir, &acpi_system_wakeup_device_fops);
519 
520 	return 0;
521 }
522