aboutsummaryrefslogtreecommitdiff
path: root/drivers/acpi/proc.c
blob: aa1227a7e3f23e349ed5050680d4fef8c135cfc8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/export.h>
#include <linux/suspend.h>
#include <linux/bcd.h>
#include <asm/uaccess.h>

#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>

#ifdef CONFIG_X86
#include <linux/mc146818rtc.h>
#endif

#include "sleep.h"

#define _COMPONENT		ACPI_SYSTEM_COMPONENT

/*
 * this file provides support for:
 * /proc/acpi/alarm
 * /proc/acpi/wakeup
 */

ACPI_MODULE_NAME("sleep")

#if defined(CONFIG_RTC_DRV_CMOS) || defined(CONFIG_RTC_DRV_CMOS_MODULE) || !defined(CONFIG_X86)
/* use /sys/class/rtc/rtcX/wakealarm instead; it's not ACPI-specific */
#else
#define	HAVE_ACPI_LEGACY_ALARM
#endif

#ifdef	HAVE_ACPI_LEGACY_ALARM

static u32 cmos_bcd_read(int offset, int rtc_control);

static int acpi_system_alarm_seq_show(struct seq_file *seq, void *offset)
{
	u32 sec, min, hr;
	u32 day, mo, yr, cent = 0;
	u32 today = 0;
	unsigned char rtc_control = 0;
	unsigned long flags;

	spin_lock_irqsave(&rtc_lock, flags);

	rtc_control = CMOS_READ(RTC_CONTROL);
	sec = cmos_bcd_read(RTC_SECONDS_ALARM, rtc_control);
	min = cmos_bcd_read(RTC_MINUTES_ALARM, rtc_control);
	hr = cmos_bcd_read(RTC_HOURS_ALARM, rtc_control);

	/* If we ever get an FACP with proper values... */
	if (acpi_gbl_FADT.day_alarm) {
		/* ACPI spec: only low 6 its should be cared */
		day = CMOS_READ(acpi_gbl_FADT.day_alarm) & 0x3F;
		if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
			day = bcd2bin(day);
	} else
		day = cmos_bcd_read(RTC_DAY_OF_MONTH, rtc_control);
	if (acpi_gbl_FADT.month_alarm)
		mo = cmos_bcd_read(acpi_gbl_FADT.month_alarm, rtc_control);
	else {
		mo = cmos_bcd_read(RTC_MONTH, rtc_control);
		today = cmos_bcd_read(RTC_DAY_OF_MONTH, rtc_control);
	}
	if (acpi_gbl_FADT.century)
		cent = cmos_bcd_read(acpi_gbl_FADT.century, rtc_control);

	yr = cmos_bcd_read(RTC_YEAR, rtc_control);

	spin_unlock_irqrestore(&rtc_lock, flags);

	/* we're trusting the FADT (see above) */
	if (!acpi_gbl_FADT.century)
		/* If we're not trusting the FADT, we should at least make it
		 * right for _this_ century... ehm, what is _this_ century?
		 *
		 * TBD:
		 *  ASAP: find piece of code in the kernel, e.g. star tracker driver,
		 *        which we can trust to determine the century correctly. Atom
		 *        watch driver would be nice, too...
		 *
		 *  if that has not happened, change for first release in 2050:
		 *        if (yr<50)
		 *                yr += 2100;
		 *        else
		 *                yr += 2000;   // current line of code
		 *
		 *  if that has not happened either, please do on 2099/12/31:23:59:59
		 *        s/2000/2100
		 *
		 */
		yr += 2000;
	else
		yr += cent * 100;

	/*
	 * Show correct dates for alarms up to a month into the future.
	 * This solves issues for nearly all situations with the common
	 * 30-day alarm clocks in PC hardware.
	 */
	if (day < today) {
		if (mo < 12) {
			mo += 1;
		} else {
			mo = 1;
			yr += 1;
		}
	}

	seq_printf(seq, "%4.4u-", yr);
	(mo > 12) ? seq_puts(seq, "**-") : seq_printf(seq, "%2.2u-", mo);
	(day > 31) ? seq_puts(seq, "** ") : seq_printf(seq, "%2.2u ", day);
	(hr > 23) ? seq_puts(seq, "**:") : seq_printf(seq, "%2.2u:", hr);
	(min > 59) ? seq_puts(seq, "**:") : seq_printf(seq, "%2.2u:", min);
	(sec > 59) ? seq_puts(seq, "**\n") : seq_printf(seq, "%2.2u\n", sec);

	return 0;
}

static int acpi_system_alarm_open_fs(struct inode *inode, struct file *file)
{
	return single_open(file, acpi_system_alarm_seq_show, PDE_DATA(inode));
}

static int get_date_field(char **p, u32 * value)
{
	char *next = NULL;
	char *string_end = NULL;
	int result = -EINVAL;

	/*
	 * Try to find delimeter, only to insert null.  The end of the
	 * string won't have one, but is still valid.
	 */
	if (*p == NULL)
		return result;

	next = strpbrk(*p, "- :");
	if (next)
		*next++ = '\0';

	*value = simple_strtoul(*p, &string_end, 10);

	/* Signal success if we got a good digit */
	if (string_end != *p)
		result = 0;

	if (next)
		*p = next;
	else
		*p = NULL;

	return result;
}

/* Read a possibly BCD register, always return binary */
static u32 cmos_bcd_read(int offset, int rtc_control)
{
	u32 val = CMOS_READ(offset);
	if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
		val = bcd2bin(val);
	return val;
}

/* Write binary value into possibly BCD register */
static void cmos_bcd_write(u32 val, int offset, int rtc_control)
{
	if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
		val = bin2bcd(val);
	CMOS_WRITE(val, offset);
}

static ssize_t
acpi_system_write_alarm(struct file *file,
			const char __user * buffer, size_t count, loff_t * ppos)
{
	int result = 0;
	char alarm_string[30] = { '\0' };
	char *p = alarm_string;
	u32 sec, min, hr, day, mo, yr;
	int adjust = 0;
	unsigned char rtc_control = 0;

	if (count > sizeof(alarm_string) - 1)
		return -EINVAL;

	if (copy_from_user(alarm_string, buffer, count))
		return -EFAULT;

	alarm_string[count] = '\0';

	/* check for time adjustment */
	if (alarm_string[0] == '+') {
		p++;
		adjust = 1;
	}

	if ((result = get_date_field(&p, &yr)))
		goto end;
	if ((result = get_date_field(&p, &mo)))
		goto end;
	if ((result = get_date_field(&p, &day)))
		goto end;
	if ((result = get_date_field(&p, &hr)))
		goto end;
	if ((result = get_date_field(&p, &min)))
		goto end;
	if ((result = get_date_field(&p, &sec)))
		goto end;

	spin_lock_irq(&rtc_lock);

	rtc_control = CMOS_READ(RTC_CONTROL);

	if (adjust) {
		yr += cmos_bcd_read(RTC_YEAR, rtc_control);
		mo += cmos_bcd_read(RTC_MONTH, rtc_control);
		day += cmos_bcd_read(RTC_DAY_OF_MONTH, rtc_control);
		hr += cmos_bcd_read(RTC_HOURS, rtc_control);
		min += cmos_bcd_read(RTC_MINUTES, rtc_control);
		sec += cmos_bcd_read(RTC_SECONDS, rtc_control);
	}

	spin_unlock_irq(&rtc_lock);

	if (sec > 59) {
		min += sec/60;
		sec = sec%60;
	}
	if (min > 59) {
		hr += min/60;
		min = min%60;
	}
	if (hr > 23) {
		day += hr/24;
		hr = hr%24;
	}
	if (day > 31) {
		mo += day/32;
		day = day%32;
	}
	if (mo > 12) {
		yr += mo/13;
		mo = mo%13;
	}

	spin_lock_irq(&rtc_lock);
	/*
	 * Disable alarm interrupt before setting alarm timer or else
	 * when ACPI_EVENT_RTC is enabled, a spurious ACPI interrupt occurs
	 */
	rtc_control &= ~RTC_AIE;
	CMOS_WRITE(rtc_control, RTC_CONTROL);
	CMOS_READ(RTC_INTR_FLAGS);

	/* write the fields the rtc knows about */
	cmos_bcd_write(hr, RTC_HOURS_ALARM, rtc_control);
	cmos_bcd_write(min, RTC_MINUTES_ALARM, rtc_control);
	cmos_bcd_write(sec, RTC_SECONDS_ALARM, rtc_control);

	/*
	 * If the system supports an enhanced alarm it will have non-zero
	 * offsets into the CMOS RAM here -- which for some reason are pointing
	 * to the RTC area of memory.
	 */
	if (acpi_gbl_FADT.day_alarm)
		cmos_bcd_write(day, acpi_gbl_FADT.day_alarm, rtc_control);
	if (acpi_gbl_FADT.month_alarm)
		cmos_bcd_write(mo, acpi_gbl_FADT.month_alarm, rtc_control);
	if (acpi_gbl_FADT.century) {
		if (adjust)
			yr += cmos_bcd_read(acpi_gbl_FADT.century, rtc_control) * 100;
		cmos_bcd_write(yr / 100, acpi_gbl_FADT.century, rtc_control);
	}
	/* enable the rtc alarm interrupt */
	rtc_control |= RTC_AIE;
	CMOS_WRITE(rtc_control, RTC_CONTROL);
	CMOS_READ(RTC_INTR_FLAGS);

	spin_unlock_irq(&rtc_lock);

	acpi_clear_event(ACPI_EVENT_RTC);
	acpi_enable_event(ACPI_EVENT_RTC, 0);

	*ppos += count;

	result = 0;
      end:
	return result ? result : count;
}
#endif				/* HAVE_ACPI_LEGACY_ALARM */

static int
acpi_system_wakeup_device_seq_show(struct seq_file *seq, void *offset)
{
	struct list_head *node, *next;

	seq_printf(seq, "Device\tS-state\t  Status   Sysfs node\n");

	mutex_lock(&acpi_device_lock);
	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
		struct acpi_device *dev =
		    container_of(node, struct acpi_device, wakeup_list);
		struct acpi_device_physical_node *entry;

		if (!dev->wakeup.flags.valid)
			continue;

		seq_printf(seq, "%s\t  S%d\t",
			   dev->pnp.bus_id,
			   (u32) dev->wakeup.sleep_state);

		if (!dev->physical_node_count) {
			seq_printf(seq, "%c%-8s\n",
				dev->wakeup.flags.run_wake ? '*' : ' ',
				device_may_wakeup(&dev->dev) ?
					"enabled" : "disabled");
		} else {
			struct device *ldev;
			list_for_each_entry(entry, &dev->physical_node_list,
					node) {
				ldev = get_device(entry->dev);
				if (!ldev)
					continue;

				if (&entry->node !=
						dev->physical_node_list.next)
					seq_printf(seq, "\t\t");

				seq_printf(seq, "%c%-8s  %s:%s\n",
					dev->wakeup.flags.run_wake ? '*' : ' ',
					(device_may_wakeup(&dev->dev) ||
					(ldev && device_may_wakeup(ldev))) ?
					"enabled" : "disabled",
					ldev->bus ? ldev->bus->name :
					"no-bus", dev_name(ldev));
				put_device(ldev);
			}
		}
	}
	mutex_unlock(&acpi_device_lock);
	return 0;
}

static void physical_device_enable_wakeup(struct acpi_device *adev)
{
	struct acpi_device_physical_node *entry;

	list_for_each_entry(entry,
		&adev->physical_node_list, node)
		if (entry->dev && device_can_wakeup(entry->dev)) {
			bool enable = !device_may_wakeup(entry->dev);
			device_set_wakeup_enable(entry->dev, enable);
		}
}

static ssize_t
acpi_system_write_wakeup_device(struct file *file,
				const char __user * buffer,
				size_t count, loff_t * ppos)
{
	struct list_head *node, *next;
	char strbuf[5];
	char str[5] = "";

	if (count > 4)
		count = 4;

	if (copy_from_user(strbuf, buffer, count))
		return -EFAULT;
	strbuf[count] = '\0';
	sscanf(strbuf, "%s", str);

	mutex_lock(&acpi_device_lock);
	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
		struct acpi_device *dev =
		    container_of(node, struct acpi_device, wakeup_list);
		if (!dev->wakeup.flags.valid)
			continue;

		if (!strncmp(dev->pnp.bus_id, str, 4)) {
			if (device_can_wakeup(&dev->dev)) {
				bool enable = !device_may_wakeup(&dev->dev);
				device_set_wakeup_enable(&dev->dev, enable);
			} else {
				physical_device_enable_wakeup(dev);
			}
			break;
		}
	}
	mutex_unlock(&acpi_device_lock);
	return count;
}

static int
acpi_system_wakeup_device_open_fs(struct inode *inode, struct file *file)
{
	return single_open(file, acpi_system_wakeup_device_seq_show,
			   PDE_DATA(inode));
}

static const struct file_operations acpi_system_wakeup_device_fops = {
	.owner = THIS_MODULE,
	.open = acpi_system_wakeup_device_open_fs,
	.read = seq_read,
	.write = acpi_system_write_wakeup_device,
	.llseek = seq_lseek,
	.release = single_release,
};

#ifdef	HAVE_ACPI_LEGACY_ALARM
static const struct file_operations acpi_system_alarm_fops = {
	.owner = THIS_MODULE,
	.open = acpi_system_alarm_open_fs,
	.read = seq_read,
	.write = acpi_system_write_alarm,
	.llseek = seq_lseek,
	.release = single_release,
};

static u32 rtc_handler(void *context)
{
	acpi_clear_event(ACPI_EVENT_RTC);
	acpi_disable_event(ACPI_EVENT_RTC, 0);

	return ACPI_INTERRUPT_HANDLED;
}
#endif				/* HAVE_ACPI_LEGACY_ALARM */

int __init acpi_sleep_proc_init(void)
{
#ifdef	HAVE_ACPI_LEGACY_ALARM
	/* 'alarm' [R/W] */
	proc_create("alarm", S_IFREG | S_IRUGO | S_IWUSR,
		    acpi_root_dir, &acpi_system_alarm_fops);

	acpi_install_fixed_event_handler(ACPI_EVENT_RTC, rtc_handler, NULL);
	/*
	 * Disable the RTC event after installing RTC handler.
	 * Only when RTC alarm is set will it be enabled.
	 */
	acpi_clear_event(ACPI_EVENT_RTC);
	acpi_disable_event(ACPI_EVENT_RTC, 0);
#endif				/* HAVE_ACPI_LEGACY_ALARM */

	/* 'wakeup device' [R/W] */
	proc_create("wakeup", S_IFREG | S_IRUGO | S_IWUSR,
		    acpi_root_dir, &acpi_system_wakeup_device_fops);

	return 0;
}