ACPI: Add interface to register/unregister device to/from power resources

Devices may share same list of power resources in _PR0, for example

Device(Dev0)
{
	Name (_PR0, Package (0x01)
	{
		P0PR,
		P1PR
	})
}

Device(Dev1)
{
	Name (_PR0, Package (0x01)
	{
		P0PR,
		P1PR
	}
}

Assume Dev0 and Dev1 were runtime suspended.
Then Dev0 is resumed first and it goes into D0 state.
But Dev1 is left in D0_Uninitialised state.

This is wrong. In this case, Dev1 must be resumed too.

In order to hand this case, each power resource maintains a list of
devices which relies on it.

When power resource is ON, it will check if the devices on its list
can be resumed. The device can only be resumed when all the power
resouces of its _PR0 are ON.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 6cd5b6403a7b..e168fffe1db5 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -323,6 +323,8 @@ int acpi_bus_set_power(acpi_handle handle, int state);
 int acpi_bus_update_power(acpi_handle handle, int *state_p);
 bool acpi_bus_power_manageable(acpi_handle handle);
 bool acpi_bus_can_wakeup(acpi_handle handle);
+int acpi_power_resource_register_device(struct device *dev, acpi_handle handle);
+void acpi_power_resource_unregister_device(struct device *dev, acpi_handle handle);
 #ifdef CONFIG_ACPI_PROC_EVENT
 int acpi_bus_generate_proc_event(struct acpi_device *device, u8 type, int data);
 int acpi_bus_generate_proc_event4(const char *class, const char *bid, u8 type, int data);