[PATCH v4 2/5] ACPI / property: Don't evaluate objects for devices w/o handle

From: Lukas Wunner
Date: Tue Aug 01 2017 - 08:11:39 EST


Fabricated devices such as LNXPWRBN lack a handle, causing evaluation
of _CCA and _DSD to always fail with AE_BAD_PARAMETER. While that is
merely a (negligible) waste of processing power, evaluating a _DSM for
them (such as Apple's device properties _DSM which we're about to add)
results in an ugly error:

ACPI: \: failed to evaluate _DSM (0x1001)

Avoid by not evaluating _DSD and the upcoming _DSM for devices without
handle.

Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Acked-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
---
drivers/acpi/property.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index a65c09cc223f..834e01bee015 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -338,6 +338,9 @@ void acpi_init_properties(struct acpi_device *adev)

INIT_LIST_HEAD(&adev->data.subnodes);

+ if (!adev->handle)
+ return;
+
/*
* Check if ACPI_DT_NAMESPACE_HID is present and inthat case we fill in
* Device Tree compatible properties for this device.
--
2.11.0