- 根目录:
- drivers
- acpi
- proc.c
#include <linux/proc_fs.h>
#include <linux/seq_file.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(inode)->data);
}
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 device *ldev;
if (!dev->wakeup.flags.valid)
continue;
ldev = acpi_get_physical_device(dev->handle);
seq_printf(seq, "%s\t S%d\t%c%-8s ",
dev->pnp.bus_id,
(u32) dev->wakeup.sleep_state,
dev->wakeup.flags.run_wake ? '*' : ' ',
(device_may_wakeup(&dev->dev)
|| (ldev && device_may_wakeup(ldev))) ?
"enabled" : "disabled");
if (ldev)
seq_printf(seq, "%s:%s",
ldev->bus ? ldev->bus->name : "no-bus",
dev_name(ldev));
seq_printf(seq, "\n");
put_device(ldev);
}
mutex_unlock(&acpi_device_lock);
return 0;
}
static void physical_device_enable_wakeup(struct acpi_device *adev)
{
struct device *dev = acpi_get_physical_device(adev->handle);
if (dev && device_can_wakeup(dev)) {
bool enable = !device_may_wakeup(dev);
device_set_wakeup_enable(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] = "";
unsigned int len = count;
if (len > 4)
len = 4;
if (len < 0)
return -EFAULT;
if (copy_from_user(strbuf, buffer, len))
return -EFAULT;
strbuf[len] = '\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(inode)->data);
}
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;
}