---
 drivers/acpi/bus.c |    5 +++++
 1 file changed, 5 insertions(+)

Index: linux-2.6/drivers/acpi/bus.c
===================================================================
--- linux-2.6.orig/drivers/acpi/bus.c
+++ linux-2.6/drivers/acpi/bus.c
@@ -256,6 +256,11 @@ int acpi_bus_set_power(acpi_handle handl
 	if (result)
 		return result;
 
+	if (!strcmp(acpi_device_hid(device), "PNP0C0B")) {
+		printk("Rui: Change %s state from %d to %d\n", device->pnp.bus_id, device->power.state, state);
+		dump_stack();
+	}
+
 	if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
 		return -EINVAL;