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path: root/drivers/acpi/processor_idle.c
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Diffstat (limited to 'drivers/acpi/processor_idle.c')
-rw-r--r--drivers/acpi/processor_idle.c323
1 files changed, 91 insertions, 232 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 47a8caa89db..3dca36d4ad2 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -28,19 +28,14 @@
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
-#include <linux/kernel.h>
#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/cpufreq.h>
-#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/dmi.h>
-#include <linux/moduleparam.h>
-#include <linux/sched.h> /* need_resched() */
-#include <linux/pm_qos.h>
+#include <linux/sched.h> /* need_resched() */
#include <linux/clockchips.h>
#include <linux/cpuidle.h>
-#include <linux/irqflags.h>
+#include <linux/syscore_ops.h>
+#include <acpi/processor.h>
/*
* Include the apic definitions for x86 to have the APIC timer related defines
@@ -52,22 +47,11 @@
#include <asm/apic.h>
#endif
-#include <asm/io.h>
-#include <asm/uaccess.h>
-
-#include <acpi/acpi_bus.h>
-#include <acpi/processor.h>
-#include <asm/processor.h>
-
#define PREFIX "ACPI: "
#define ACPI_PROCESSOR_CLASS "processor"
#define _COMPONENT ACPI_PROCESSOR_COMPONENT
ACPI_MODULE_NAME("processor_idle");
-#define PM_TIMER_TICK_NS (1000000000ULL/PM_TIMER_FREQUENCY)
-#define C2_OVERHEAD 1 /* 1us */
-#define C3_OVERHEAD 1 /* 1us */
-#define PM_TIMER_TICKS_TO_US(p) (((p) * 1000)/(PM_TIMER_FREQUENCY/1000))
static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER;
module_param(max_cstate, uint, 0000);
@@ -79,10 +63,14 @@ module_param(bm_check_disable, uint, 0000);
static unsigned int latency_factor __read_mostly = 2;
module_param(latency_factor, uint, 0644);
+static DEFINE_PER_CPU(struct cpuidle_device *, acpi_cpuidle_device);
+
+static DEFINE_PER_CPU(struct acpi_processor_cx * [CPUIDLE_STATE_MAX],
+ acpi_cstate);
+
static int disabled_by_idle_boot_param(void)
{
return boot_option_idle_override == IDLE_POLL ||
- boot_option_idle_override == IDLE_FORCE_MWAIT ||
boot_option_idle_override == IDLE_HALT;
}
@@ -106,9 +94,7 @@ static int set_max_cstate(const struct dmi_system_id *id)
return 0;
}
-/* Actually this shouldn't be __cpuinitdata, would be better to fix the
- callers to only run once -AK */
-static struct dmi_system_id __cpuinitdata processor_power_dmi_table[] = {
+static struct dmi_system_id processor_power_dmi_table[] = {
{ set_max_cstate, "Clevo 5600D", {
DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"),
DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")},
@@ -131,17 +117,10 @@ static struct dmi_system_id __cpuinitdata processor_power_dmi_table[] = {
*/
static void acpi_safe_halt(void)
{
- current_thread_info()->status &= ~TS_POLLING;
- /*
- * TS_POLLING-cleared state must be visible before we
- * test NEED_RESCHED:
- */
- smp_mb();
- if (!need_resched()) {
+ if (!tif_need_resched()) {
safe_halt();
local_irq_disable();
}
- current_thread_info()->status |= TS_POLLING;
}
#ifdef ARCH_APICTIMER_STOPS_ON_C3
@@ -221,45 +200,41 @@ static void lapic_timer_state_broadcast(struct acpi_processor *pr,
#endif
-/*
- * Suspend / resume control
- */
-static int acpi_idle_suspend;
+#ifdef CONFIG_PM_SLEEP
static u32 saved_bm_rld;
-static void acpi_idle_bm_rld_save(void)
+static int acpi_processor_suspend(void)
{
acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld);
+ return 0;
}
-static void acpi_idle_bm_rld_restore(void)
+
+static void acpi_processor_resume(void)
{
- u32 resumed_bm_rld;
+ u32 resumed_bm_rld = 0;
acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld);
+ if (resumed_bm_rld == saved_bm_rld)
+ return;
- if (resumed_bm_rld != saved_bm_rld)
- acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld);
+ acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld);
}
-int acpi_processor_suspend(struct acpi_device * device, pm_message_t state)
-{
- if (acpi_idle_suspend == 1)
- return 0;
+static struct syscore_ops acpi_processor_syscore_ops = {
+ .suspend = acpi_processor_suspend,
+ .resume = acpi_processor_resume,
+};
- acpi_idle_bm_rld_save();
- acpi_idle_suspend = 1;
- return 0;
+void acpi_processor_syscore_init(void)
+{
+ register_syscore_ops(&acpi_processor_syscore_ops);
}
-int acpi_processor_resume(struct acpi_device * device)
+void acpi_processor_syscore_exit(void)
{
- if (acpi_idle_suspend == 0)
- return 0;
-
- acpi_idle_bm_rld_restore();
- acpi_idle_suspend = 0;
- return 0;
+ unregister_syscore_ops(&acpi_processor_syscore_ops);
}
+#endif /* CONFIG_PM_SLEEP */
#if defined(CONFIG_X86)
static void tsc_check_state(int state)
@@ -288,9 +263,6 @@ static void tsc_check_state(int state) { return; }
static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
{
- if (!pr)
- return -EINVAL;
-
if (!pr->pblk)
return -ENODEV;
@@ -313,16 +285,16 @@ static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5;
/* determine latencies from FADT */
- pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.C2latency;
- pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.C3latency;
+ pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.c2_latency;
+ pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.c3_latency;
/*
* FADT specified C2 latency must be less than or equal to
* 100 microseconds.
*/
- if (acpi_gbl_FADT.C2latency > ACPI_PROCESSOR_MAX_C2_LATENCY) {
+ if (acpi_gbl_FADT.c2_latency > ACPI_PROCESSOR_MAX_C2_LATENCY) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
- "C2 latency too large [%d]\n", acpi_gbl_FADT.C2latency));
+ "C2 latency too large [%d]\n", acpi_gbl_FADT.c2_latency));
/* invalidate C2 */
pr->power.states[ACPI_STATE_C2].address = 0;
}
@@ -331,9 +303,9 @@ static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
* FADT supplied C3 latency must be less than or equal to
* 1000 microseconds.
*/
- if (acpi_gbl_FADT.C3latency > ACPI_PROCESSOR_MAX_C3_LATENCY) {
+ if (acpi_gbl_FADT.c3_latency > ACPI_PROCESSOR_MAX_C3_LATENCY) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
- "C3 latency too large [%d]\n", acpi_gbl_FADT.C3latency));
+ "C3 latency too large [%d]\n", acpi_gbl_FADT.c3_latency));
/* invalidate C3 */
pr->power.states[ACPI_STATE_C3].address = 0;
}
@@ -495,8 +467,6 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
if (obj->type != ACPI_TYPE_INTEGER)
continue;
- cx.power = obj->integer.value;
-
current_count++;
memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx));
@@ -595,7 +565,6 @@ static void acpi_processor_power_verify_c3(struct acpi_processor *pr,
*/
cx->valid = 1;
- cx->latency_ticks = cx->latency;
/*
* On older chipsets, BM_RLD needs to be set
* in order for Bus Master activity to wake the
@@ -627,8 +596,7 @@ static int acpi_processor_power_verify(struct acpi_processor *pr)
case ACPI_STATE_C2:
if (!cx->address)
break;
- cx->valid = 1;
- cx->latency_ticks = cx->latency; /* Normalize latency */
+ cx->valid = 1;
break;
case ACPI_STATE_C3:
@@ -749,37 +717,17 @@ static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
static int acpi_idle_enter_c1(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
- ktime_t kt1, kt2;
- s64 idle_time;
struct acpi_processor *pr;
- struct cpuidle_state_usage *state_usage = &dev->states_usage[index];
- struct acpi_processor_cx *cx = cpuidle_get_statedata(state_usage);
+ struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);
pr = __this_cpu_read(processors);
- dev->last_residency = 0;
if (unlikely(!pr))
return -EINVAL;
- local_irq_disable();
-
- if (acpi_idle_suspend) {
- local_irq_enable();
- cpu_relax();
- return -EBUSY;
- }
-
lapic_timer_state_broadcast(pr, cx, 1);
- kt1 = ktime_get_real();
acpi_idle_do_entry(cx);
- kt2 = ktime_get_real();
- idle_time = ktime_to_us(ktime_sub(kt2, kt1));
-
- /* Update device last_residency*/
- dev->last_residency = (int)idle_time;
- local_irq_enable();
- cx->usage++;
lapic_timer_state_broadcast(pr, cx, 0);
return index;
@@ -793,8 +741,7 @@ static int acpi_idle_enter_c1(struct cpuidle_device *dev,
*/
static int acpi_idle_play_dead(struct cpuidle_device *dev, int index)
{
- struct cpuidle_state_usage *state_usage = &dev->states_usage[index];
- struct acpi_processor_cx *cx = cpuidle_get_statedata(state_usage);
+ struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);
ACPI_FLUSH_CPU_CACHE();
@@ -824,40 +771,19 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
struct acpi_processor *pr;
- struct cpuidle_state_usage *state_usage = &dev->states_usage[index];
- struct acpi_processor_cx *cx = cpuidle_get_statedata(state_usage);
- ktime_t kt1, kt2;
- s64 idle_time_ns;
- s64 idle_time;
+ struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);
pr = __this_cpu_read(processors);
- dev->last_residency = 0;
if (unlikely(!pr))
return -EINVAL;
- local_irq_disable();
-
- if (acpi_idle_suspend) {
- local_irq_enable();
- cpu_relax();
- return -EBUSY;
- }
-
- if (cx->entry_method != ACPI_CSTATE_FFH) {
- current_thread_info()->status &= ~TS_POLLING;
- /*
- * TS_POLLING-cleared state must be visible before we test
- * NEED_RESCHED:
- */
- smp_mb();
-
- if (unlikely(need_resched())) {
- current_thread_info()->status |= TS_POLLING;
- local_irq_enable();
- return -EINVAL;
- }
- }
+#ifdef CONFIG_HOTPLUG_CPU
+ if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
+ !pr->flags.has_cst &&
+ !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
+ return acpi_idle_enter_c1(dev, drv, CPUIDLE_DRIVER_STATE_START);
+#endif
/*
* Must be done before busmaster disable as we might need to
@@ -868,29 +794,13 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev,
if (cx->type == ACPI_STATE_C3)
ACPI_FLUSH_CPU_CACHE();
- kt1 = ktime_get_real();
/* Tell the scheduler that we are going deep-idle: */
sched_clock_idle_sleep_event();
acpi_idle_do_entry(cx);
- kt2 = ktime_get_real();
- idle_time_ns = ktime_to_ns(ktime_sub(kt2, kt1));
- idle_time = idle_time_ns;
- do_div(idle_time, NSEC_PER_USEC);
-
- /* Update device last_residency*/
- dev->last_residency = (int)idle_time;
-
- /* Tell the scheduler how much we idled: */
- sched_clock_idle_wakeup_event(idle_time_ns);
- local_irq_enable();
- if (cx->entry_method != ACPI_CSTATE_FFH)
- current_thread_info()->status |= TS_POLLING;
-
- cx->usage++;
+ sched_clock_idle_wakeup_event(0);
lapic_timer_state_broadcast(pr, cx, 0);
- cx->time += idle_time;
return index;
}
@@ -909,55 +819,30 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
struct acpi_processor *pr;
- struct cpuidle_state_usage *state_usage = &dev->states_usage[index];
- struct acpi_processor_cx *cx = cpuidle_get_statedata(state_usage);
- ktime_t kt1, kt2;
- s64 idle_time_ns;
- s64 idle_time;
-
+ struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);
pr = __this_cpu_read(processors);
- dev->last_residency = 0;
if (unlikely(!pr))
return -EINVAL;
+#ifdef CONFIG_HOTPLUG_CPU
+ if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
+ !pr->flags.has_cst &&
+ !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
+ return acpi_idle_enter_c1(dev, drv, CPUIDLE_DRIVER_STATE_START);
+#endif
+
if (!cx->bm_sts_skip && acpi_idle_bm_check()) {
if (drv->safe_state_index >= 0) {
return drv->states[drv->safe_state_index].enter(dev,
drv, drv->safe_state_index);
} else {
- local_irq_disable();
- if (!acpi_idle_suspend)
- acpi_safe_halt();
- local_irq_enable();
+ acpi_safe_halt();
return -EBUSY;
}
}
- local_irq_disable();
-
- if (acpi_idle_suspend) {
- local_irq_enable();
- cpu_relax();
- return -EBUSY;
- }
-
- if (cx->entry_method != ACPI_CSTATE_FFH) {
- current_thread_info()->status &= ~TS_POLLING;
- /*
- * TS_POLLING-cleared state must be visible before we test
- * NEED_RESCHED:
- */
- smp_mb();
-
- if (unlikely(need_resched())) {
- current_thread_info()->status |= TS_POLLING;
- local_irq_enable();
- return -EINVAL;
- }
- }
-
acpi_unlazy_tlb(smp_processor_id());
/* Tell the scheduler that we are going deep-idle: */
@@ -968,7 +853,6 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev,
*/
lapic_timer_state_broadcast(pr, cx, 1);
- kt1 = ktime_get_real();
/*
* disable bus master
* bm_check implies we need ARB_DIS
@@ -999,25 +883,10 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev,
c3_cpu_count--;
raw_spin_unlock(&c3_lock);
}
- kt2 = ktime_get_real();
- idle_time_ns = ktime_to_ns(ktime_sub(kt2, kt1));
- idle_time = idle_time_ns;
- do_div(idle_time, NSEC_PER_USEC);
-
- /* Update device last_residency*/
- dev->last_residency = (int)idle_time;
- /* Tell the scheduler how much we idled: */
- sched_clock_idle_wakeup_event(idle_time_ns);
-
- local_irq_enable();
- if (cx->entry_method != ACPI_CSTATE_FFH)
- current_thread_info()->status |= TS_POLLING;
-
- cx->usage++;
+ sched_clock_idle_wakeup_event(0);
lapic_timer_state_broadcast(pr, cx, 0);
- cx->time += idle_time;
return index;
}
@@ -1031,13 +900,13 @@ struct cpuidle_driver acpi_idle_driver = {
* device i.e. per-cpu data
*
* @pr: the ACPI processor
+ * @dev : the cpuidle device
*/
-static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr)
+static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
+ struct cpuidle_device *dev)
{
int i, count = CPUIDLE_DRIVER_STATE_START;
struct acpi_processor_cx *cx;
- struct cpuidle_state_usage *state_usage;
- struct cpuidle_device *dev = &pr->power.dev;
if (!pr->flags.power_setup_done)
return -EINVAL;
@@ -1046,6 +915,9 @@ static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr)
return -EINVAL;
}
+ if (!dev)
+ return -EINVAL;
+
dev->cpu = pr->id;
if (max_cstate == 0)
@@ -1053,27 +925,17 @@ static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr)
for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
cx = &pr->power.states[i];
- state_usage = &dev->states_usage[count];
if (!cx->valid)
continue;
-#ifdef CONFIG_HOTPLUG_CPU
- if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
- !pr->flags.has_cst &&
- !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
- continue;
-#endif
-
- cpuidle_set_statedata(state_usage, cx);
+ per_cpu(acpi_cstate[count], dev->cpu) = cx;
count++;
if (count == CPUIDLE_STATE_MAX)
break;
}
- dev->state_count = count;
-
if (!count)
return -EINVAL;
@@ -1114,13 +976,6 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
if (!cx->valid)
continue;
-#ifdef CONFIG_HOTPLUG_CPU
- if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
- !pr->flags.has_cst &&
- !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
- continue;
-#endif
-
state = &drv->states[count];
snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);
strncpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
@@ -1169,26 +1024,24 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
int acpi_processor_hotplug(struct acpi_processor *pr)
{
int ret = 0;
+ struct cpuidle_device *dev;
if (disabled_by_idle_boot_param())
return 0;
- if (!pr)
- return -EINVAL;
-
- if (nocst) {
+ if (nocst)
return -ENODEV;
- }
if (!pr->flags.power_setup_done)
return -ENODEV;
+ dev = per_cpu(acpi_cpuidle_device, pr->id);
cpuidle_pause_and_lock();
- cpuidle_disable_device(&pr->power.dev);
+ cpuidle_disable_device(dev);
acpi_processor_get_power_info(pr);
if (pr->flags.power) {
- acpi_processor_setup_cpuidle_cx(pr);
- ret = cpuidle_enable_device(&pr->power.dev);
+ acpi_processor_setup_cpuidle_cx(pr, dev);
+ ret = cpuidle_enable_device(dev);
}
cpuidle_resume_and_unlock();
@@ -1199,13 +1052,11 @@ int acpi_processor_cst_has_changed(struct acpi_processor *pr)
{
int cpu;
struct acpi_processor *_pr;
+ struct cpuidle_device *dev;
if (disabled_by_idle_boot_param())
return 0;
- if (!pr)
- return -EINVAL;
-
if (nocst)
return -ENODEV;
@@ -1229,10 +1080,12 @@ int acpi_processor_cst_has_changed(struct acpi_processor *pr)
_pr = per_cpu(processors, cpu);
if (!_pr || !_pr->flags.power_setup_done)
continue;
- cpuidle_disable_device(&_pr->power.dev);
+ dev = per_cpu(acpi_cpuidle_device, cpu);
+ cpuidle_disable_device(dev);
}
/* Populate Updated C-state information */
+ acpi_processor_get_power_info(pr);
acpi_processor_setup_cpuidle_states(pr);
/* Enable all cpuidle devices */
@@ -1242,8 +1095,9 @@ int acpi_processor_cst_has_changed(struct acpi_processor *pr)
continue;
acpi_processor_get_power_info(_pr);
if (_pr->flags.power) {
- acpi_processor_setup_cpuidle_cx(_pr);
- cpuidle_enable_device(&_pr->power.dev);
+ dev = per_cpu(acpi_cpuidle_device, cpu);
+ acpi_processor_setup_cpuidle_cx(_pr, dev);
+ cpuidle_enable_device(dev);
}
}
put_online_cpus();
@@ -1255,11 +1109,11 @@ int acpi_processor_cst_has_changed(struct acpi_processor *pr)
static int acpi_processor_registered;
-int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
- struct acpi_device *device)
+int acpi_processor_power_init(struct acpi_processor *pr)
{
acpi_status status = 0;
int retval;
+ struct cpuidle_device *dev;
static int first_run;
if (disabled_by_idle_boot_param())
@@ -1275,9 +1129,6 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
first_run++;
}
- if (!pr)
- return -EINVAL;
-
if (acpi_gbl_FADT.cst_control && !nocst) {
status =
acpi_os_write_port(acpi_gbl_FADT.smi_command, acpi_gbl_FADT.cst_control, 8);
@@ -1305,11 +1156,18 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
printk(KERN_DEBUG "ACPI: %s registered with cpuidle\n",
acpi_idle_driver.name);
}
+
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev)
+ return -ENOMEM;
+ per_cpu(acpi_cpuidle_device, pr->id) = dev;
+
+ acpi_processor_setup_cpuidle_cx(pr, dev);
+
/* Register per-cpu cpuidle_device. Cpuidle driver
* must already be registered before registering device
*/
- acpi_processor_setup_cpuidle_cx(pr);
- retval = cpuidle_register_device(&pr->power.dev);
+ retval = cpuidle_register_device(dev);
if (retval) {
if (acpi_processor_registered == 0)
cpuidle_unregister_driver(&acpi_idle_driver);
@@ -1320,14 +1178,15 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
return 0;
}
-int acpi_processor_power_exit(struct acpi_processor *pr,
- struct acpi_device *device)
+int acpi_processor_power_exit(struct acpi_processor *pr)
{
+ struct cpuidle_device *dev = per_cpu(acpi_cpuidle_device, pr->id);
+
if (disabled_by_idle_boot_param())
return 0;
if (pr->flags.power) {
- cpuidle_unregister_device(&pr->power.dev);
+ cpuidle_unregister_device(dev);
acpi_processor_registered--;
if (acpi_processor_registered == 0)
cpuidle_unregister_driver(&acpi_idle_driver);