ACPI: support acpi_device_ops .notify methods
This patch adds support for ACPI device driver .notify() methods. If
such a method is present, Linux/ACPI installs a handler for device
notifications (but not for system notifications such as Bus Check,
Device Check, etc). When a device notification occurs, Linux/ACPI
passes it on to the driver's .notify() method.
In most cases, this removes the need for drivers to install their own
handlers for device-specific notifications.
For fixed hardware devices like some power and sleep buttons, there's
no notification value because there's no control method to execute a
Notify opcode. When a fixed hardware device generates an event, we
handle it the same as a regular device notification, except we send
a ACPI_FIXED_HARDWARE_EVENT value. This is outside the normal 0x0-0xff
range used by Notify opcodes.
Several drivers install their own handlers for system Bus Check and
Device Check notifications so they can support hot-plug. This patch
doesn't affect that usage.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/include/acpi/acpi_drivers.h b/include/acpi/acpi_drivers.h
index 241d227..0352c8f 100644
--- a/include/acpi/acpi_drivers.h
+++ b/include/acpi/acpi_drivers.h
@@ -67,6 +67,16 @@
#define ACPI_BAY_HID "LNXIOBAY"
#define ACPI_DOCK_HID "LNXDOCK"
+/*
+ * For fixed hardware buttons, we fabricate acpi_devices with HID
+ * ACPI_BUTTON_HID_POWERF or ACPI_BUTTON_HID_SLEEPF. Fixed hardware
+ * signals only an event; it doesn't supply a notification value.
+ * To allow drivers to treat notifications from fixed hardware the
+ * same as those from real devices, we turn the events into this
+ * notification value.
+ */
+#define ACPI_FIXED_HARDWARE_EVENT 0x100
+
/* --------------------------------------------------------------------------
PCI
-------------------------------------------------------------------------- */