16 files changed, 213 insertions, 13 deletions

diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX
index 8d556707bb68..30b327a116ea 100644
--- a/Documentation/00-INDEX
+++ b/Documentation/00-INDEX
@@ -109,6 +109,8 @@ cpu-hotplug.txt
         - document describing CPU hotplug support in the Linux kernel.
 cpu-load.txt
         - document describing how CPU load statistics are collected.
+cpuidle/
+        - info on CPU_IDLE, CPU idle state management subsystem.
 cpusets.txt
         - documents the cpusets feature; assign CPUs and Mem to a set of tasks.
 cputopology.txt
diff --git a/Documentation/cpuidle/core.txt b/Documentation/cpuidle/core.txt
new file mode 100644
index 000000000000..63ecc5dc9d8a
--- /dev/null
+++ b/Documentation/cpuidle/core.txt
@@ -0,0 +1,23 @@
+
+                Supporting multiple CPU idle levels in kernel
+
+                                cpuidle
+
+General Information:
+
+Various CPUs today support multiple idle levels that are differentiated
+by varying exit latencies and power consumption during idle.
+cpuidle is a generic in-kernel infrastructure that separates
+idle policy (governor) from idle mechanism (driver) and provides a
+standardized infrastructure to support independent development of
+governors and drivers.
+
+cpuidle resides under drivers/cpuidle.
+
+Boot options:
+"cpuidle_sysfs_switch"
+enables current_governor interface in /sys/devices/system/cpu/cpuidle/,
+which can be used to switch governors at run time. This boot option
+is meant for developer testing only. In normal usage, kernel picks the
+best governor based on governor ratings.
+SEE ALSO: sysfs.txt in this directory.
diff --git a/Documentation/cpuidle/driver.txt b/Documentation/cpuidle/driver.txt
new file mode 100644
index 000000000000..7a9e09ece931
--- /dev/null
+++ b/Documentation/cpuidle/driver.txt
@@ -0,0 +1,31 @@
+
+
+                Supporting multiple CPU idle levels in kernel
+
+                                cpuidle drivers
+
+
+
+
+cpuidle driver hooks into the cpuidle infrastructure and handles the
+architecture/platform dependent part of CPU idle states. Driver
+provides the platform idle state detection capability and also
+has mechanisms in place to support actual entry-exit into CPU idle states.
+
+cpuidle driver initializes the cpuidle_device structure for each CPU device
+and registers with cpuidle using cpuidle_register_device.
+
+It can also support the dynamic changes (like battery <-> AC), by using
+cpuidle_pause_and_lock, cpuidle_disable_device and cpuidle_enable_device,
+cpuidle_resume_and_unlock.
+
+Interfaces:
+extern int cpuidle_register_driver(struct cpuidle_driver *drv);
+extern void cpuidle_unregister_driver(struct cpuidle_driver *drv);
+extern int cpuidle_register_device(struct cpuidle_device *dev);
+extern void cpuidle_unregister_device(struct cpuidle_device *dev);
+
+extern void cpuidle_pause_and_lock(void);
+extern void cpuidle_resume_and_unlock(void);
+extern int cpuidle_enable_device(struct cpuidle_device *dev);
+extern void cpuidle_disable_device(struct cpuidle_device *dev);
diff --git a/Documentation/cpuidle/governor.txt b/Documentation/cpuidle/governor.txt
new file mode 100644
index 000000000000..12c6bd50c9f6
--- /dev/null
+++ b/Documentation/cpuidle/governor.txt
@@ -0,0 +1,29 @@
+
+
+
+                Supporting multiple CPU idle levels in kernel
+
+                                cpuidle governors
+
+
+
+
+cpuidle governor is policy routine that decides what idle state to enter at
+any given time. cpuidle core uses different callbacks to the governor.
+
+* enable() to enable governor for a particular device
+* disable() to disable governor for a particular device
+* select() to select an idle state to enter
+* reflect() called after returning from the idle state, which can be used
+  by the governor for some record keeping.
+
+More than one governor can be registered at the same time and
+users can switch between drivers using /sysfs interface (when enabled).
+More than one governor part is supported for developers to easily experiment
+with different governors. By default, most optimal governor based on your
+kernel configuration and platform will be selected by cpuidle.
+
+Interfaces:
+extern int cpuidle_register_governor(struct cpuidle_governor *gov);
+extern void cpuidle_unregister_governor(struct cpuidle_governor *gov);
+struct cpuidle_governor
diff --git a/Documentation/cpuidle/sysfs.txt b/Documentation/cpuidle/sysfs.txt
new file mode 100644
index 000000000000..50d7b1642759
--- /dev/null
+++ b/Documentation/cpuidle/sysfs.txt
@@ -0,0 +1,79 @@
+
+
+                Supporting multiple CPU idle levels in kernel
+
+                                cpuidle sysfs
+
+System global cpuidle related information and tunables are under
+/sys/devices/system/cpu/cpuidle
+
+The current interfaces in this directory has self-explanatory names:
+* current_driver
+* current_governor_ro
+
+With cpuidle_sysfs_switch boot option (meant for developer testing)
+following objects are visible instead.
+* current_driver
+* available_governors
+* current_governor
+In this case users can switch the governor at run time by writing
+to current_governor.
+
+
+Per logical CPU specific cpuidle information are under
+/sys/devices/system/cpu/cpuX/cpuidle
+for each online cpu X
+
+--------------------------------------------------------------------------------
+# ls -lR /sys/devices/system/cpu/cpu0/cpuidle/
+/sys/devices/system/cpu/cpu0/cpuidle/:
+total 0
+drwxr-xr-x 2 root root 0 Feb  8 10:42 state0
+drwxr-xr-x 2 root root 0 Feb  8 10:42 state1
+drwxr-xr-x 2 root root 0 Feb  8 10:42 state2
+drwxr-xr-x 2 root root 0 Feb  8 10:42 state3
+
+/sys/devices/system/cpu/cpu0/cpuidle/state0:
+total 0
+-r--r--r-- 1 root root 4096 Feb  8 10:42 desc
+-r--r--r-- 1 root root 4096 Feb  8 10:42 latency
+-r--r--r-- 1 root root 4096 Feb  8 10:42 name
+-r--r--r-- 1 root root 4096 Feb  8 10:42 power
+-r--r--r-- 1 root root 4096 Feb  8 10:42 time
+-r--r--r-- 1 root root 4096 Feb  8 10:42 usage
+
+/sys/devices/system/cpu/cpu0/cpuidle/state1:
+total 0
+-r--r--r-- 1 root root 4096 Feb  8 10:42 desc
+-r--r--r-- 1 root root 4096 Feb  8 10:42 latency
+-r--r--r-- 1 root root 4096 Feb  8 10:42 name
+-r--r--r-- 1 root root 4096 Feb  8 10:42 power
+-r--r--r-- 1 root root 4096 Feb  8 10:42 time
+-r--r--r-- 1 root root 4096 Feb  8 10:42 usage
+
+/sys/devices/system/cpu/cpu0/cpuidle/state2:
+total 0
+-r--r--r-- 1 root root 4096 Feb  8 10:42 desc
+-r--r--r-- 1 root root 4096 Feb  8 10:42 latency
+-r--r--r-- 1 root root 4096 Feb  8 10:42 name
+-r--r--r-- 1 root root 4096 Feb  8 10:42 power
+-r--r--r-- 1 root root 4096 Feb  8 10:42 time
+-r--r--r-- 1 root root 4096 Feb  8 10:42 usage
+
+/sys/devices/system/cpu/cpu0/cpuidle/state3:
+total 0
+-r--r--r-- 1 root root 4096 Feb  8 10:42 desc
+-r--r--r-- 1 root root 4096 Feb  8 10:42 latency
+-r--r--r-- 1 root root 4096 Feb  8 10:42 name
+-r--r--r-- 1 root root 4096 Feb  8 10:42 power
+-r--r--r-- 1 root root 4096 Feb  8 10:42 time
+-r--r--r-- 1 root root 4096 Feb  8 10:42 usage
+--------------------------------------------------------------------------------
+
+
+* desc : Small description about the idle state (string)
+* latency : Latency to exit out of this idle state (in microseconds)
+* name : Name of the idle state (string)
+* power : Power consumed while in this idle state (in milliwatts)
+* time : Total time spent in this idle state (in microseconds)
+* usage : Number of times this state was entered (count)
diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c
index 10b67170b133..8ca3557a6d59 100644
--- a/arch/x86/kernel/acpi/cstate.c
+++ b/arch/x86/kernel/acpi/cstate.c
@@ -126,6 +126,8 @@ int acpi_processor_ffh_cstate_probe(unsigned int cpu,
                 printk(KERN_DEBUG "Monitor-Mwait will be used to enter C-%d "
                        "state\n", cx->type);
         }
+        snprintf(cx->desc, ACPI_CX_DESC_LEN, "ACPI FFH INTEL MWAIT 0x%x",
+                 cx->address);
 
 out:
         set_cpus_allowed(current, saved_mask);
diff --git a/drivers/acpi/event.c b/drivers/acpi/event.c
index 5479dc0eeeec..abec1ca94cf4 100644
--- a/drivers/acpi/event.c
+++ b/drivers/acpi/event.c
@@ -110,7 +110,7 @@ static const struct file_operations acpi_system_event_ops = {
 #endif  /* CONFIG_ACPI_PROC_EVENT */
 
 /* ACPI notifier chain */
-BLOCKING_NOTIFIER_HEAD(acpi_chain_head);
+static BLOCKING_NOTIFIER_HEAD(acpi_chain_head);
 
 int acpi_notifier_call_chain(struct acpi_device *dev, u32 type, u32 data)
 {
diff --git a/drivers/acpi/hardware/hwsleep.c b/drivers/acpi/hardware/hwsleep.c
index 058d0be5cbe2..4290e0193097 100644
--- a/drivers/acpi/hardware/hwsleep.c
+++ b/drivers/acpi/hardware/hwsleep.c
@@ -616,6 +616,7 @@ acpi_status acpi_leave_sleep_state(u8 sleep_state)
                 return_ACPI_STATUS(status);
         }
 
+        arg.integer.value = sleep_state;
         status = acpi_evaluate_object(NULL, METHOD_NAME__WAK, &arg_list, NULL);
         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
                 ACPI_EXCEPTION((AE_INFO, status, "During Method _WAK"));
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 0467171dbdb8..8edba7b678eb 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -325,7 +325,7 @@ acpi_os_predefined_override(const struct acpi_predefined_names *init_val,
 }
 
 #ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD
-struct acpi_table_header *acpi_find_dsdt_initrd(void)
+static struct acpi_table_header *acpi_find_dsdt_initrd(void)
 {
         struct file *firmware_file;
         mm_segment_t oldfs;
@@ -419,7 +419,7 @@ acpi_os_table_override(struct acpi_table_header * existing_table,
 }
 
 #ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD
-int __init acpi_no_initrd_override_setup(char *s)
+static int __init acpi_no_initrd_override_setup(char *s)
 {
         acpi_no_initrd_override = 1;
         return 1;
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 32003fdc91e8..980e1c33e6c5 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -945,11 +945,16 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
                                  * Otherwise, ignore this info and continue.
                                  */
                                 cx.entry_method = ACPI_CSTATE_HALT;
+                                snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
                         } else {
                                 continue;
                         }
+                } else {
+                        snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
+                                 cx.address);
                 }
 
+
                 obj = &(element->package.elements[2]);
                 if (obj->type != ACPI_TYPE_INTEGER)
                         continue;
@@ -1420,6 +1425,14 @@ static int acpi_idle_enter_c1(struct cpuidle_device *dev,
                 return 0;
 
         local_irq_disable();
+
+        /* Do not access any ACPI IO ports in suspend path */
+        if (acpi_idle_suspend) {
+                acpi_safe_halt();
+                local_irq_enable();
+                return 0;
+        }
+
         if (pr->flags.bm_check)
                 acpi_idle_update_bm_rld(pr, cx);
 
@@ -1643,6 +1656,11 @@ static int acpi_processor_setup_cpuidle(struct acpi_processor *pr)
                 return -EINVAL;
         }
 
+        for (i = 0; i < CPUIDLE_STATE_MAX; i++) {
+                dev->states[i].name[0] = '\0';
+                dev->states[i].desc[0] = '\0';
+        }
+
         for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
                 cx = &pr->power.states[i];
                 state = &dev->states[count];
@@ -1659,6 +1677,7 @@ static int acpi_processor_setup_cpuidle(struct acpi_processor *pr)
                 cpuidle_set_statedata(state, cx);
 
                 snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);
+                strncpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
                 state->exit_latency = cx->latency;
                 state->target_residency = cx->latency * latency_factor;
                 state->power_usage = cx->power;
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 60f71e6345e3..d73663a52324 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -219,7 +219,8 @@ static void poll_idle_init(struct cpuidle_device *dev)
 
         cpuidle_set_statedata(state, NULL);
 
-        snprintf(state->name, CPUIDLE_NAME_LEN, "C0 (poll idle)");
+        snprintf(state->name, CPUIDLE_NAME_LEN, "C0");
+        snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE");
         state->exit_latency = 0;
         state->target_residency = 0;
         state->power_usage = -1;
diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c
index 088ea74edd34..69102ca05685 100644
--- a/drivers/cpuidle/sysfs.c
+++ b/drivers/cpuidle/sysfs.c
@@ -218,16 +218,23 @@ static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
         return sprintf(buf, "%u\n", state->_name);\
 }
 
-static ssize_t show_state_name(struct cpuidle_state *state, char *buf)
-{
-        return sprintf(buf, "%s\n", state->name);
+#define define_show_state_str_function(_name) \
+static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
+{ \
+        if (state->_name[0] == '\0')\
+                return sprintf(buf, "<null>\n");\
+        return sprintf(buf, "%s\n", state->_name);\
 }
 
 define_show_state_function(exit_latency)
 define_show_state_function(power_usage)
 define_show_state_function(usage)
 define_show_state_function(time)
+define_show_state_str_function(name)
+define_show_state_str_function(desc)
+
 define_one_state_ro(name, show_state_name);
+define_one_state_ro(desc, show_state_desc);
 define_one_state_ro(latency, show_state_exit_latency);
 define_one_state_ro(power, show_state_power_usage);
 define_one_state_ro(usage, show_state_usage);
@@ -235,6 +242,7 @@ define_one_state_ro(time, show_state_time);
 
 static struct attribute *cpuidle_state_default_attrs[] = {
         &attr_name.attr,
+        &attr_desc.attr,
         &attr_latency.attr,
         &attr_power.attr,
         &attr_usage.attr,
diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c
index 7ba1acad5402..e2c7edd206a6 100644
--- a/drivers/misc/thinkpad_acpi.c
+++ b/drivers/misc/thinkpad_acpi.c
@@ -1689,7 +1689,7 @@ static ssize_t hotkey_wakeup_reason_show(struct device *dev,
 static struct device_attribute dev_attr_hotkey_wakeup_reason =
         __ATTR(wakeup_reason, S_IRUGO, hotkey_wakeup_reason_show, NULL);
 
-void hotkey_wakeup_reason_notify_change(void)
+static void hotkey_wakeup_reason_notify_change(void)
 {
         if (tp_features.hotkey_mask)
                 sysfs_notify(&tpacpi_pdev->dev.kobj, NULL,
@@ -1708,7 +1708,7 @@ static struct device_attribute dev_attr_hotkey_wakeup_hotunplug_complete =
         __ATTR(wakeup_hotunplug_complete, S_IRUGO,
                hotkey_wakeup_hotunplug_complete_show, NULL);
 
-void hotkey_wakeup_hotunplug_complete_notify_change(void)
+static void hotkey_wakeup_hotunplug_complete_notify_change(void)
 {
         if (tp_features.hotkey_mask)
                 sysfs_notify(&tpacpi_pdev->dev.kobj, NULL,
diff --git a/drivers/pnp/pnpacpi/core.c b/drivers/pnp/pnpacpi/core.c
index 662b4c279cfc..c283a9a70d83 100644
--- a/drivers/pnp/pnpacpi/core.c
+++ b/drivers/pnp/pnpacpi/core.c
@@ -36,7 +36,7 @@ static int num = 0;
  * have irqs (PIC, Timer) because we call acpi_register_gsi.
  * Finally, only devices that have a CRS method need to be in this list.
  */
-static struct __initdata acpi_device_id excluded_id_list[] = {
+static struct acpi_device_id excluded_id_list[] __initdata = {
         {"PNP0C09", 0},         /* EC */
         {"PNP0C0F", 0},         /* Link device */
         {"PNP0000", 0},         /* PIC */
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index cdc8004cfd12..06480bcabfdc 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -32,9 +32,11 @@
 #define DOMAIN_COORD_TYPE_SW_ANY        0xfd
 #define DOMAIN_COORD_TYPE_HW_ALL        0xfe
 
-#define ACPI_CSTATE_SYSTEMIO    (0)
-#define ACPI_CSTATE_FFH         (1)
-#define ACPI_CSTATE_HALT        (2)
+#define ACPI_CSTATE_SYSTEMIO    0
+#define ACPI_CSTATE_FFH         1
+#define ACPI_CSTATE_HALT        2
+
+#define ACPI_CX_DESC_LEN        32
 
 /* Power Management */
 
@@ -74,6 +76,7 @@ struct acpi_processor_cx {
         u64 time;
         struct acpi_processor_cx_policy promotion;
         struct acpi_processor_cx_policy demotion;
+        char desc[ACPI_CX_DESC_LEN];
 };
 
 struct acpi_processor_power {
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index 385d45b616db..6b72a4584086 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -19,6 +19,7 @@
 
 #define CPUIDLE_STATE_MAX       8
 #define CPUIDLE_NAME_LEN        16
+#define CPUIDLE_DESC_LEN        32
 
 struct cpuidle_device;
 
@@ -29,6 +30,7 @@ struct cpuidle_device;
 
 struct cpuidle_state {
         char            name[CPUIDLE_NAME_LEN];
+        char            desc[CPUIDLE_DESC_LEN];
         void            *driver_data;
 
         unsigned int    flags;