diff options
| -rw-r--r-- | drivers/acpi/glue.c | 25 | ||||
| -rw-r--r-- | drivers/acpi/internal.h | 1 | ||||
| -rw-r--r-- | drivers/acpi/scan.c | 6 |
3 files changed, 32 insertions, 0 deletions
diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c index 7a33a6d985f8..1cfafa254e3d 100644 --- a/drivers/acpi/glue.c +++ b/drivers/acpi/glue.c @@ -340,3 +340,28 @@ void acpi_device_notify_remove(struct device *dev) acpi_unbind_one(dev); } + +int acpi_dev_turn_off_if_unused(struct device *dev, void *not_used) +{ + struct acpi_device *adev = to_acpi_device(dev); + + /* + * Skip device objects with device IDs, because they may be in use even + * if they are not companions of any physical device objects. + */ + if (adev->pnp.type.hardware_id) + return 0; + + mutex_lock(&adev->physical_node_lock); + + /* + * Device objects without device IDs are not in use if they have no + * corresponding physical device objects. + */ + if (list_empty(&adev->physical_node_list)) + acpi_device_set_power(adev, ACPI_STATE_D3_COLD); + + mutex_unlock(&adev->physical_node_lock); + + return 0; +} diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index d91b560e8867..8fbdc172864b 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -117,6 +117,7 @@ bool acpi_device_is_battery(struct acpi_device *adev); bool acpi_device_is_first_physical_node(struct acpi_device *adev, const struct device *dev); int acpi_bus_register_early_device(int type); +int acpi_dev_turn_off_if_unused(struct device *dev, void *not_used); /* -------------------------------------------------------------------------- Device Matching and Notification diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 5b54c80b9d32..770b82483d74 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -2559,6 +2559,12 @@ int __init acpi_scan_init(void) } } + /* + * Make sure that power management resources are not blocked by ACPI + * device objects with no users. + */ + bus_for_each_dev(&acpi_bus_type, NULL, NULL, acpi_dev_turn_off_if_unused); + acpi_turn_off_unused_power_resources(); acpi_scan_initialized = true; |