From: "Rafael J. Wysocki" <rafael.j.wysocki@xxxxxxxxx> If the boot EC comes from the DSDT, its ACPI handle is equal to the handle of a device object with the PNP0C09 device ID. If that device object is passed to acpi_ec_add(), it is not necessary to allocate a new EC structure for it and parse it, because that has been done already, so change the function to use the fast path in that case. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> --- drivers/acpi/ec.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 4ed0c6155d3f..920a08c01ab6 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -1614,7 +1614,8 @@ static int acpi_ec_add(struct acpi_device *device) strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); strcpy(acpi_device_class(device), ACPI_EC_CLASS); - if (!strcmp(acpi_device_hid(device), ACPI_ECDT_HID)) { + if ((boot_ec && boot_ec->handle == device->handle) || + !strcmp(acpi_device_hid(device), ACPI_ECDT_HID)) { /* Fast path: this device corresponds to the boot EC. */ ec = boot_ec; } else { -- 2.16.4