[PATCH 32/48] ACPI / PM: Prevent acpi_power_get_inferred_state() from making changes

Len Brown
2011-01-12T18:00:17Z

From: Rafael J. Wysocki <rjw@sisk.pl>

acpi_power_get_inferred_state() should not update
device->power.state behind the back of its caller, so make it return
the state via a pointer instead.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
---
drivers/acpi/bus.c | 3 ++-
drivers/acpi/internal.h | 2 +-
drivers/acpi/power.c | 12 ++++--------
3 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index d68bd61..a9fe8e6 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -222,7 +222,8 @@ int acpi_bus_get_power(acpi_handle handle, int *state)
* indirectly (via power resources).
*/
if (device->power.flags.power_resources) {
- result = acpi_power_get_inferred_state(device);
+ result = acpi_power_get_inferred_state(device,
+ &device->power.state);
if (result)
return result;
} else if (device->power.flags.explicit_get) {
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index a212bfe..2cc0148 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -41,7 +41,7 @@ static inline int acpi_debugfs_init(void) { return 0; }
int acpi_power_init(void);
int acpi_device_sleep_wake(struct acpi_device *dev,
int enable, int sleep_state, int dev_state);
-int acpi_power_get_inferred_state(struct acpi_device *device);
+int acpi_power_get_inferred_state(struct acpi_device *device, int *state);
int acpi_power_transition(struct acpi_device *device, int state);
extern int acpi_power_nocheck;

diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index 4c9c2fb..9bd1b60 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -423,19 +423,16 @@ int acpi_disable_wakeup_device_power(struct acpi_device *dev)
Device Power Management
-------------------------------------------------------------------------- */

-int acpi_power_get_inferred_state(struct acpi_device *device)
+int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
{
int result = 0;
struct acpi_handle_list *list = NULL;
int list_state = 0;
int i = 0;

-
- if (!device)
+ if (!device || !state)
return -EINVAL;

- device->power.state = ACPI_STATE_UNKNOWN;
-
/*
* We know a device's inferred power state when all the resources
* required for a given D-state are 'on'.
@@ -450,13 +447,12 @@ int acpi_power_get_inferred_state(struct acpi_device *device)
return result;

if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
- device->power.state = i;
+ *state = i;
return 0;
}
}

- device->power.state = ACPI_STATE_D3;
-
+ *state = ACPI_STATE_D3;
return 0;
}

--
1.7.4.rc1.7.g2cf08