ACPI: drivers/acpi: elide a non-zero test on a result that is never 0
[linux/fpc-iii.git] / drivers / acpi / sleep / proc.c
blobf8df5217d477ee525c30f4c1050bf7cc8eb6e35b
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>
7 #include <acpi/acpi_bus.h>
8 #include <acpi/acpi_drivers.h>
10 #ifdef CONFIG_X86
11 #include <linux/mc146818rtc.h>
12 #endif
14 #include "sleep.h"
16 #define _COMPONENT ACPI_SYSTEM_COMPONENT
19 * this file provides support for:
20 * /proc/acpi/sleep
21 * /proc/acpi/alarm
22 * /proc/acpi/wakeup
25 ACPI_MODULE_NAME("sleep")
26 #ifdef CONFIG_ACPI_PROCFS
27 static int acpi_system_sleep_seq_show(struct seq_file *seq, void *offset)
29 int i;
31 ACPI_FUNCTION_TRACE("acpi_system_sleep_seq_show");
33 for (i = 0; i <= ACPI_STATE_S5; i++) {
34 if (sleep_states[i]) {
35 seq_printf(seq, "S%d ", i);
39 seq_puts(seq, "\n");
41 return 0;
44 static int acpi_system_sleep_open_fs(struct inode *inode, struct file *file)
46 return single_open(file, acpi_system_sleep_seq_show, PDE(inode)->data);
49 static ssize_t
50 acpi_system_write_sleep(struct file *file,
51 const char __user * buffer, size_t count, loff_t * ppos)
53 char str[12];
54 u32 state = 0;
55 int error = 0;
57 if (count > sizeof(str) - 1)
58 goto Done;
59 memset(str, 0, sizeof(str));
60 if (copy_from_user(str, buffer, count))
61 return -EFAULT;
63 /* Check for S4 bios request */
64 if (!strcmp(str, "4b")) {
65 error = acpi_suspend(4);
66 goto Done;
68 state = simple_strtoul(str, NULL, 0);
69 #ifdef CONFIG_HIBERNATION
70 if (state == 4) {
71 error = hibernate();
72 goto Done;
74 #endif
75 error = acpi_suspend(state);
76 Done:
77 return error ? error : count;
79 #endif /* CONFIG_ACPI_PROCFS */
81 #if defined(CONFIG_RTC_DRV_CMOS) || defined(CONFIG_RTC_DRV_CMOS_MODULE) || !defined(CONFIG_X86)
82 /* use /sys/class/rtc/rtcX/wakealarm instead; it's not ACPI-specific */
83 #else
84 #define HAVE_ACPI_LEGACY_ALARM
85 #endif
87 #ifdef HAVE_ACPI_LEGACY_ALARM
89 static int acpi_system_alarm_seq_show(struct seq_file *seq, void *offset)
91 u32 sec, min, hr;
92 u32 day, mo, yr, cent = 0;
93 unsigned char rtc_control = 0;
94 unsigned long flags;
96 ACPI_FUNCTION_TRACE("acpi_system_alarm_seq_show");
98 spin_lock_irqsave(&rtc_lock, flags);
100 sec = CMOS_READ(RTC_SECONDS_ALARM);
101 min = CMOS_READ(RTC_MINUTES_ALARM);
102 hr = CMOS_READ(RTC_HOURS_ALARM);
103 rtc_control = CMOS_READ(RTC_CONTROL);
105 /* If we ever get an FACP with proper values... */
106 if (acpi_gbl_FADT.day_alarm)
107 /* ACPI spec: only low 6 its should be cared */
108 day = CMOS_READ(acpi_gbl_FADT.day_alarm) & 0x3F;
109 else
110 day = CMOS_READ(RTC_DAY_OF_MONTH);
111 if (acpi_gbl_FADT.month_alarm)
112 mo = CMOS_READ(acpi_gbl_FADT.month_alarm);
113 else
114 mo = CMOS_READ(RTC_MONTH);
115 if (acpi_gbl_FADT.century)
116 cent = CMOS_READ(acpi_gbl_FADT.century);
118 yr = CMOS_READ(RTC_YEAR);
120 spin_unlock_irqrestore(&rtc_lock, flags);
122 if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
123 BCD_TO_BIN(sec);
124 BCD_TO_BIN(min);
125 BCD_TO_BIN(hr);
126 BCD_TO_BIN(day);
127 BCD_TO_BIN(mo);
128 BCD_TO_BIN(yr);
129 BCD_TO_BIN(cent);
132 /* we're trusting the FADT (see above) */
133 if (!acpi_gbl_FADT.century)
134 /* If we're not trusting the FADT, we should at least make it
135 * right for _this_ century... ehm, what is _this_ century?
137 * TBD:
138 * ASAP: find piece of code in the kernel, e.g. star tracker driver,
139 * which we can trust to determine the century correctly. Atom
140 * watch driver would be nice, too...
142 * if that has not happened, change for first release in 2050:
143 * if (yr<50)
144 * yr += 2100;
145 * else
146 * yr += 2000; // current line of code
148 * if that has not happened either, please do on 2099/12/31:23:59:59
149 * s/2000/2100
152 yr += 2000;
153 else
154 yr += cent * 100;
156 seq_printf(seq, "%4.4u-", yr);
157 (mo > 12) ? seq_puts(seq, "**-") : seq_printf(seq, "%2.2u-", mo);
158 (day > 31) ? seq_puts(seq, "** ") : seq_printf(seq, "%2.2u ", day);
159 (hr > 23) ? seq_puts(seq, "**:") : seq_printf(seq, "%2.2u:", hr);
160 (min > 59) ? seq_puts(seq, "**:") : seq_printf(seq, "%2.2u:", min);
161 (sec > 59) ? seq_puts(seq, "**\n") : seq_printf(seq, "%2.2u\n", sec);
163 return 0;
166 static int acpi_system_alarm_open_fs(struct inode *inode, struct file *file)
168 return single_open(file, acpi_system_alarm_seq_show, PDE(inode)->data);
171 static int get_date_field(char **p, u32 * value)
173 char *next = NULL;
174 char *string_end = NULL;
175 int result = -EINVAL;
178 * Try to find delimeter, only to insert null. The end of the
179 * string won't have one, but is still valid.
181 if (*p == NULL)
182 return result;
184 next = strpbrk(*p, "- :");
185 if (next)
186 *next++ = '\0';
188 *value = simple_strtoul(*p, &string_end, 10);
190 /* Signal success if we got a good digit */
191 if (string_end != *p)
192 result = 0;
194 if (next)
195 *p = next;
196 else
197 *p = NULL;
199 return result;
202 /* Read a possibly BCD register, always return binary */
203 static u32 cmos_bcd_read(int offset, int rtc_control)
205 u32 val = CMOS_READ(offset);
206 if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
207 BCD_TO_BIN(val);
208 return val;
211 /* Write binary value into possibly BCD register */
212 static void cmos_bcd_write(u32 val, int offset, int rtc_control)
214 if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
215 BIN_TO_BCD(val);
216 CMOS_WRITE(val, offset);
219 static ssize_t
220 acpi_system_write_alarm(struct file *file,
221 const char __user * buffer, size_t count, loff_t * ppos)
223 int result = 0;
224 char alarm_string[30] = { '\0' };
225 char *p = alarm_string;
226 u32 sec, min, hr, day, mo, yr;
227 int adjust = 0;
228 unsigned char rtc_control = 0;
230 ACPI_FUNCTION_TRACE("acpi_system_write_alarm");
232 if (count > sizeof(alarm_string) - 1)
233 return_VALUE(-EINVAL);
235 if (copy_from_user(alarm_string, buffer, count))
236 return_VALUE(-EFAULT);
238 alarm_string[count] = '\0';
240 /* check for time adjustment */
241 if (alarm_string[0] == '+') {
242 p++;
243 adjust = 1;
246 if ((result = get_date_field(&p, &yr)))
247 goto end;
248 if ((result = get_date_field(&p, &mo)))
249 goto end;
250 if ((result = get_date_field(&p, &day)))
251 goto end;
252 if ((result = get_date_field(&p, &hr)))
253 goto end;
254 if ((result = get_date_field(&p, &min)))
255 goto end;
256 if ((result = get_date_field(&p, &sec)))
257 goto end;
259 spin_lock_irq(&rtc_lock);
261 rtc_control = CMOS_READ(RTC_CONTROL);
263 if (adjust) {
264 yr += cmos_bcd_read(RTC_YEAR, rtc_control);
265 mo += cmos_bcd_read(RTC_MONTH, rtc_control);
266 day += cmos_bcd_read(RTC_DAY_OF_MONTH, rtc_control);
267 hr += cmos_bcd_read(RTC_HOURS, rtc_control);
268 min += cmos_bcd_read(RTC_MINUTES, rtc_control);
269 sec += cmos_bcd_read(RTC_SECONDS, rtc_control);
272 spin_unlock_irq(&rtc_lock);
274 if (sec > 59) {
275 min += sec/60;
276 sec = sec%60;
278 if (min > 59) {
279 hr += min/60;
280 min = min%60;
282 if (hr > 23) {
283 day += hr/24;
284 hr = hr%24;
286 if (day > 31) {
287 mo += day/32;
288 day = day%32;
290 if (mo > 12) {
291 yr += mo/13;
292 mo = mo%13;
295 spin_lock_irq(&rtc_lock);
297 * Disable alarm interrupt before setting alarm timer or else
298 * when ACPI_EVENT_RTC is enabled, a spurious ACPI interrupt occurs
300 rtc_control &= ~RTC_AIE;
301 CMOS_WRITE(rtc_control, RTC_CONTROL);
302 CMOS_READ(RTC_INTR_FLAGS);
304 /* write the fields the rtc knows about */
305 cmos_bcd_write(hr, RTC_HOURS_ALARM, rtc_control);
306 cmos_bcd_write(min, RTC_MINUTES_ALARM, rtc_control);
307 cmos_bcd_write(sec, RTC_SECONDS_ALARM, rtc_control);
310 * If the system supports an enhanced alarm it will have non-zero
311 * offsets into the CMOS RAM here -- which for some reason are pointing
312 * to the RTC area of memory.
314 if (acpi_gbl_FADT.day_alarm)
315 cmos_bcd_write(day, acpi_gbl_FADT.day_alarm, rtc_control);
316 if (acpi_gbl_FADT.month_alarm)
317 cmos_bcd_write(mo, acpi_gbl_FADT.month_alarm, rtc_control);
318 if (acpi_gbl_FADT.century)
319 cmos_bcd_write(yr / 100, acpi_gbl_FADT.century, rtc_control);
320 /* enable the rtc alarm interrupt */
321 rtc_control |= RTC_AIE;
322 CMOS_WRITE(rtc_control, RTC_CONTROL);
323 CMOS_READ(RTC_INTR_FLAGS);
325 spin_unlock_irq(&rtc_lock);
327 acpi_clear_event(ACPI_EVENT_RTC);
328 acpi_enable_event(ACPI_EVENT_RTC, 0);
330 *ppos += count;
332 result = 0;
333 end:
334 return_VALUE(result ? result : count);
336 #endif /* HAVE_ACPI_LEGACY_ALARM */
338 extern struct list_head acpi_wakeup_device_list;
339 extern spinlock_t acpi_device_lock;
341 static int
342 acpi_system_wakeup_device_seq_show(struct seq_file *seq, void *offset)
344 struct list_head *node, *next;
346 seq_printf(seq, "Device\tS-state\t Status Sysfs node\n");
348 spin_lock(&acpi_device_lock);
349 list_for_each_safe(node, next, &acpi_wakeup_device_list) {
350 struct acpi_device *dev =
351 container_of(node, struct acpi_device, wakeup_list);
352 struct device *ldev;
354 if (!dev->wakeup.flags.valid)
355 continue;
356 spin_unlock(&acpi_device_lock);
358 ldev = acpi_get_physical_device(dev->handle);
359 seq_printf(seq, "%s\t S%d\t%c%-8s ",
360 dev->pnp.bus_id,
361 (u32) dev->wakeup.sleep_state,
362 dev->wakeup.flags.run_wake ? '*' : ' ',
363 dev->wakeup.state.enabled ? "enabled" : "disabled");
364 if (ldev)
365 seq_printf(seq, "%s:%s",
366 ldev->bus ? ldev->bus->name : "no-bus",
367 ldev->bus_id);
368 seq_printf(seq, "\n");
369 put_device(ldev);
371 spin_lock(&acpi_device_lock);
373 spin_unlock(&acpi_device_lock);
374 return 0;
377 static ssize_t
378 acpi_system_write_wakeup_device(struct file *file,
379 const char __user * buffer,
380 size_t count, loff_t * ppos)
382 struct list_head *node, *next;
383 char strbuf[5];
384 char str[5] = "";
385 int len = count;
386 struct acpi_device *found_dev = NULL;
388 if (len > 4)
389 len = 4;
391 if (copy_from_user(strbuf, buffer, len))
392 return -EFAULT;
393 strbuf[len] = '\0';
394 sscanf(strbuf, "%s", str);
396 spin_lock(&acpi_device_lock);
397 list_for_each_safe(node, next, &acpi_wakeup_device_list) {
398 struct acpi_device *dev =
399 container_of(node, struct acpi_device, wakeup_list);
400 if (!dev->wakeup.flags.valid)
401 continue;
403 if (!strncmp(dev->pnp.bus_id, str, 4)) {
404 dev->wakeup.state.enabled =
405 dev->wakeup.state.enabled ? 0 : 1;
406 found_dev = dev;
407 break;
410 if (found_dev) {
411 list_for_each_safe(node, next, &acpi_wakeup_device_list) {
412 struct acpi_device *dev = container_of(node,
413 struct
414 acpi_device,
415 wakeup_list);
417 if ((dev != found_dev) &&
418 (dev->wakeup.gpe_number ==
419 found_dev->wakeup.gpe_number)
420 && (dev->wakeup.gpe_device ==
421 found_dev->wakeup.gpe_device)) {
422 printk(KERN_WARNING
423 "ACPI: '%s' and '%s' have the same GPE, "
424 "can't disable/enable one seperately\n",
425 dev->pnp.bus_id, found_dev->pnp.bus_id);
426 dev->wakeup.state.enabled =
427 found_dev->wakeup.state.enabled;
431 spin_unlock(&acpi_device_lock);
432 return count;
435 static int
436 acpi_system_wakeup_device_open_fs(struct inode *inode, struct file *file)
438 return single_open(file, acpi_system_wakeup_device_seq_show,
439 PDE(inode)->data);
442 static const struct file_operations acpi_system_wakeup_device_fops = {
443 .open = acpi_system_wakeup_device_open_fs,
444 .read = seq_read,
445 .write = acpi_system_write_wakeup_device,
446 .llseek = seq_lseek,
447 .release = single_release,
450 #ifdef CONFIG_ACPI_PROCFS
451 static const struct file_operations acpi_system_sleep_fops = {
452 .open = acpi_system_sleep_open_fs,
453 .read = seq_read,
454 .write = acpi_system_write_sleep,
455 .llseek = seq_lseek,
456 .release = single_release,
458 #endif /* CONFIG_ACPI_PROCFS */
460 #ifdef HAVE_ACPI_LEGACY_ALARM
461 static const struct file_operations acpi_system_alarm_fops = {
462 .open = acpi_system_alarm_open_fs,
463 .read = seq_read,
464 .write = acpi_system_write_alarm,
465 .llseek = seq_lseek,
466 .release = single_release,
469 static u32 rtc_handler(void *context)
471 acpi_clear_event(ACPI_EVENT_RTC);
472 acpi_disable_event(ACPI_EVENT_RTC, 0);
474 return ACPI_INTERRUPT_HANDLED;
476 #endif /* HAVE_ACPI_LEGACY_ALARM */
478 static int __init acpi_sleep_proc_init(void)
480 struct proc_dir_entry *entry = NULL;
482 if (acpi_disabled)
483 return 0;
485 #ifdef CONFIG_ACPI_PROCFS
486 /* 'sleep' [R/W] */
487 entry =
488 create_proc_entry("sleep", S_IFREG | S_IRUGO | S_IWUSR,
489 acpi_root_dir);
490 if (entry)
491 entry->proc_fops = &acpi_system_sleep_fops;
492 #endif /* CONFIG_ACPI_PROCFS */
494 #ifdef HAVE_ACPI_LEGACY_ALARM
495 /* 'alarm' [R/W] */
496 entry =
497 create_proc_entry("alarm", S_IFREG | S_IRUGO | S_IWUSR,
498 acpi_root_dir);
499 if (entry)
500 entry->proc_fops = &acpi_system_alarm_fops;
502 acpi_install_fixed_event_handler(ACPI_EVENT_RTC, rtc_handler, NULL);
503 #endif /* HAVE_ACPI_LEGACY_ALARM */
505 /* 'wakeup device' [R/W] */
506 entry =
507 create_proc_entry("wakeup", S_IFREG | S_IRUGO | S_IWUSR,
508 acpi_root_dir);
509 if (entry)
510 entry->proc_fops = &acpi_system_wakeup_device_fops;
512 return 0;
515 late_initcall(acpi_sleep_proc_init);