* (APM) BIOS Interface Specification, Revision 1.2, February 1996.
*
* [This document is available from Microsoft at:
- * http://www.microsoft.com/hwdev/busbios/amp_12.htm]
+ * http://www.microsoft.com/whdc/archive/amp_12.mspx]
*/
-#include <linux/config.h>
#include <linux/module.h>
#include <linux/poll.h>
#include <linux/smp_lock.h>
#include <linux/dmi.h>
#include <linux/suspend.h>
+#include <linux/kthread.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/desc.h>
#include <asm/i8253.h>
+#include <asm/paravirt.h>
#include "io_ports.h"
unsigned short segment;
} apm_bios_entry;
static int clock_slowed;
-static int idle_threshold = DEFAULT_IDLE_THRESHOLD;
-static int idle_period = DEFAULT_IDLE_PERIOD;
+static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
+static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
static int set_pm_idle;
static int suspends_pending;
static int standbys_pending;
static int ignore_sys_suspend;
static int ignore_normal_resume;
-static int bounce_interval = DEFAULT_BOUNCE_INTERVAL;
+static int bounce_interval __read_mostly = DEFAULT_BOUNCE_INTERVAL;
#ifdef CONFIG_APM_RTC_IS_GMT
# define clock_cmos_diff 0
static long clock_cmos_diff;
static int got_clock_diff;
#endif
-static int debug;
-static int smp;
+static int debug __read_mostly;
+static int smp __read_mostly;
static int apm_disabled = -1;
#ifdef CONFIG_SMP
static int power_off;
#else
static int realmode_power_off;
#endif
-static int exit_kapmd;
-static int kapmd_running;
#ifdef CONFIG_APM_ALLOW_INTS
static int allow_ints = 1;
#else
static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
static struct apm_user * user_list;
static DEFINE_SPINLOCK(user_list_lock);
-static struct desc_struct bad_bios_desc = { 0, 0x00409200 };
+static const struct desc_struct bad_bios_desc = { 0, 0x00409200 };
-static char driver_version[] = "1.16ac"; /* no spaces */
+static const char driver_version[] = "1.16ac"; /* no spaces */
+
+static struct task_struct *kapmd_task;
/*
* APM event names taken from the APM 1.2 specification. These are
* the message codes that the BIOS uses to tell us about events
*/
-static char * apm_event_name[] = {
+static const char * const apm_event_name[] = {
"system standby",
"system suspend",
"normal resume",
* Also, we KNOW that for the non error case of apm_bios_call, there
* is no useful data returned in the low order 8 bits of eax.
*/
-#define APM_DO_CLI \
- if (apm_info.allow_ints) \
- local_irq_enable(); \
- else \
+
+static inline unsigned long __apm_irq_save(void)
+{
+ unsigned long flags;
+ local_save_flags(flags);
+ if (apm_info.allow_ints) {
+ if (irqs_disabled_flags(flags))
+ local_irq_enable();
+ } else
local_irq_disable();
+ return flags;
+}
+
+#define apm_irq_save(flags) \
+ do { flags = __apm_irq_save(); } while (0)
+
+static inline void apm_irq_restore(unsigned long flags)
+{
+ if (irqs_disabled_flags(flags))
+ local_irq_disable();
+ else if (irqs_disabled())
+ local_irq_enable();
+}
+
#ifdef APM_ZERO_SEGS
# define APM_DECL_SEGS \
unsigned int saved_fs; unsigned int saved_gs;
save_desc_40 = gdt[0x40 / 8];
gdt[0x40 / 8] = bad_bios_desc;
- local_save_flags(flags);
- APM_DO_CLI;
+ apm_irq_save(flags);
APM_DO_SAVE_SEGS;
apm_bios_call_asm(func, ebx_in, ecx_in, eax, ebx, ecx, edx, esi);
APM_DO_RESTORE_SEGS;
- local_irq_restore(flags);
+ apm_irq_restore(flags);
gdt[0x40 / 8] = save_desc_40;
put_cpu();
apm_restore_cpus(cpus);
* @ecx_in: ECX register value for BIOS call
* @eax: EAX register on return from the BIOS call
*
- * Make a BIOS call that does only returns one value, or just status.
+ * Make a BIOS call that returns one value only, or just status.
* If there is an error, then the error code is returned in AH
* (bits 8-15 of eax) and this function returns non-zero. This is
* used for simpler BIOS operations. This call may hold interrupts
save_desc_40 = gdt[0x40 / 8];
gdt[0x40 / 8] = bad_bios_desc;
- local_save_flags(flags);
- APM_DO_CLI;
+ apm_irq_save(flags);
APM_DO_SAVE_SEGS;
error = apm_bios_call_simple_asm(func, ebx_in, ecx_in, eax);
APM_DO_RESTORE_SEGS;
- local_irq_restore(flags);
+ apm_irq_restore(flags);
gdt[0x40 / 8] = save_desc_40;
put_cpu();
apm_restore_cpus(cpus);
int idled = 0;
int polling;
- polling = test_thread_flag(TIF_POLLING_NRFLAG);
+ polling = !!(current_thread_info()->status & TS_POLLING);
if (polling) {
- clear_thread_flag(TIF_POLLING_NRFLAG);
- smp_mb__after_clear_bit();
+ current_thread_info()->status &= ~TS_POLLING;
+ /*
+ * TS_POLLING-cleared state must be visible before we
+ * test NEED_RESCHED:
+ */
+ smp_mb();
}
if (!need_resched()) {
idled = 1;
ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax);
}
if (polling)
- set_thread_flag(TIF_POLLING_NRFLAG);
+ current_thread_info()->status |= TS_POLLING;
if (!idled)
return 0;
#define IDLE_CALC_LIMIT (HZ * 100)
#define IDLE_LEAKY_MAX 16
-static void (*original_pm_idle)(void);
-
-extern void default_idle(void);
+static void (*original_pm_idle)(void) __read_mostly;
/**
* apm_cpu_idle - cpu idling for APM capable Linux
static int apm_console_blank(int blank)
{
- int error, i;
+ int error = APM_NOT_ENGAGED; /* silence gcc */
+ int i;
u_short state;
static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
static apm_event_t get_queued_event(struct apm_user *as)
{
- as->event_tail = (as->event_tail + 1) % APM_MAX_EVENTS;
+ if (++as->event_tail >= APM_MAX_EVENTS)
+ as->event_tail = 0;
return as->events[as->event_tail];
}
for (as = user_list; as != NULL; as = as->next) {
if ((as == sender) || (!as->reader))
continue;
- as->event_head = (as->event_head + 1) % APM_MAX_EVENTS;
+ if (++as->event_head >= APM_MAX_EVENTS)
+ as->event_head = 0;
+
if (as->event_head == as->event_tail) {
static int notified;
if (notified++ == 0)
printk(KERN_ERR "apm: an event queue overflowed\n");
- as->event_tail = (as->event_tail + 1) % APM_MAX_EVENTS;
+ if (++as->event_tail >= APM_MAX_EVENTS)
+ as->event_tail = 0;
}
as->events[as->event_head] = event;
if ((!as->suser) || (!as->writer))
static void set_time(void)
{
+ struct timespec ts;
if (got_clock_diff) { /* Must know time zone in order to set clock */
- xtime.tv_sec = get_cmos_time() + clock_cmos_diff;
- xtime.tv_nsec = 0;
+ ts.tv_sec = get_cmos_time() + clock_cmos_diff;
+ ts.tv_nsec = 0;
+ do_settimeofday(&ts);
}
}
restore_processor_state();
local_irq_disable();
- write_seqlock(&xtime_lock);
- spin_lock(&i8253_lock);
- reinit_timer();
set_time();
-
- spin_unlock(&i8253_lock);
- write_sequnlock(&xtime_lock);
+ reinit_timer();
if (err == APM_NO_ERROR)
err = APM_SUCCESS;
static apm_event_t get_event(void)
{
int error;
- apm_event_t event;
+ apm_event_t event = APM_NO_EVENTS; /* silence gcc */
apm_eventinfo_t info;
static int notified;
ignore_bounce = 1;
if ((event != APM_NORMAL_RESUME)
|| (ignore_normal_resume == 0)) {
- write_seqlock_irq(&xtime_lock);
set_time();
- write_sequnlock_irq(&xtime_lock);
device_resume();
pm_send_all(PM_RESUME, (void *)0);
queue_event(event, NULL);
break;
case APM_UPDATE_TIME:
- write_seqlock_irq(&xtime_lock);
set_time();
- write_sequnlock_irq(&xtime_lock);
break;
case APM_CRITICAL_SUSPEND:
set_current_state(TASK_INTERRUPTIBLE);
for (;;) {
schedule_timeout(APM_CHECK_TIMEOUT);
- if (exit_kapmd)
+ if (kthread_should_stop())
break;
/*
* Ok, check all events, check for idle (and mark us sleeping
{
struct apm_user * as;
- as = (struct apm_user *)kmalloc(sizeof(*as), GFP_KERNEL);
+ as = kmalloc(sizeof(*as), GFP_KERNEL);
if (as == NULL) {
printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n",
sizeof(*as));
char * power_stat;
char * bat_stat;
- kapmd_running = 1;
-
- daemonize("kapmd");
-
- current->flags |= PF_NOFREEZE;
-
#ifdef CONFIG_SMP
/* 2002/08/01 - WT
* This is to avoid random crashes at boot time during initialization
console_blank_hook = NULL;
#endif
}
- kapmd_running = 0;
return 0;
}
{
struct proc_dir_entry *apm_proc;
struct desc_struct *gdt;
- int ret;
+ int err;
dmi_check_system(apm_dmi_table);
- if (apm_info.bios.version == 0) {
+ if (apm_info.bios.version == 0 || paravirt_enabled()) {
printk(KERN_INFO "apm: BIOS not found.\n");
return -ENODEV;
}
if (apm_proc)
apm_proc->owner = THIS_MODULE;
- ret = kernel_thread(apm, NULL, CLONE_KERNEL | SIGCHLD);
- if (ret < 0) {
- printk(KERN_ERR "apm: disabled - Unable to start kernel thread.\n");
- return -ENOMEM;
+ kapmd_task = kthread_create(apm, NULL, "kapmd");
+ if (IS_ERR(kapmd_task)) {
+ printk(KERN_ERR "apm: disabled - Unable to start kernel "
+ "thread.\n");
+ err = PTR_ERR(kapmd_task);
+ kapmd_task = NULL;
+ remove_proc_entry("apm", NULL);
+ return err;
}
+ kapmd_task->flags |= PF_NOFREEZE;
+ wake_up_process(kapmd_task);
if (num_online_cpus() > 1 && !smp ) {
printk(KERN_NOTICE
return 0;
}
- misc_register(&apm_device);
+ /*
+ * Note we don't actually care if the misc_device cannot be registered.
+ * this driver can do its job without it, even if userspace can't
+ * control it. just log the error
+ */
+ if (misc_register(&apm_device))
+ printk(KERN_WARNING "apm: Could not register misc device.\n");
if (HZ != 100)
idle_period = (idle_period * HZ) / 100;
remove_proc_entry("apm", NULL);
if (power_off)
pm_power_off = NULL;
- exit_kapmd = 1;
- while (kapmd_running)
- schedule();
+ if (kapmd_task) {
+ kthread_stop(kapmd_task);
+ kapmd_task = NULL;
+ }
#ifdef CONFIG_PM_LEGACY
pm_active = 0;
#endif