ACPI / PM: Add check preventing transitioning to non-D0 state from D3.
No power transitioning from D3 state up to a non-D0 state is allowed
so make acpi_device_set_power() fail and complain if such a transition
is attempted.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 07a20ee..1f0d457 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -306,6 +306,12 @@
* a lower-powered state.
*/
if (state < device->power.state) {
+ if (device->power.state >= ACPI_STATE_D3_HOT &&
+ state != ACPI_STATE_D0) {
+ printk(KERN_WARNING PREFIX
+ "Cannot transition to non-D0 state from D3\n");
+ return -ENODEV;
+ }
if (device->power.flags.power_resources) {
result = acpi_power_transition(device, state);
if (result)