diff options
| author | Matthew Garrett | 2012-05-11 16:08:26 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman | 2012-05-11 17:03:12 -0700 |
| commit | 38ac0f1b90dc9486cc039f1a4d8b0202813e5b67 (patch) | |
| tree | 906f48f2bfb685d6075b74f50bc338768014ca3e /drivers/acpi | |
| parent | 66886d6f8c9bcdee3d7fce5796dcffd6b4bc0b48 (diff) | |
ACPI: Add _PLD support
Add a simple helper function to allow drivers to obtain the physical
device location data.
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/utils.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c index b002a471c5d4..adbbc1c80a26 100644 --- a/drivers/acpi/utils.c +++ b/drivers/acpi/utils.c @@ -382,3 +382,33 @@ acpi_evaluate_reference(acpi_handle handle, } EXPORT_SYMBOL(acpi_evaluate_reference); + +acpi_status +acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld *pld) +{ + acpi_status status; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + union acpi_object *output; + + status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer); + + if (ACPI_FAILURE(status)) + return status; + + output = buffer.pointer; + + if (!output || output->type != ACPI_TYPE_PACKAGE + || !output->package.count + || output->package.elements[0].type != ACPI_TYPE_BUFFER + || output->package.elements[0].buffer.length > sizeof(*pld)) { + status = AE_TYPE; + goto out; + } + + memcpy(pld, output->package.elements[0].buffer.pointer, + output->package.elements[0].buffer.length); +out: + kfree(buffer.pointer); + return status; +} +EXPORT_SYMBOL(acpi_get_physical_device_location); |