From c804826be9b528b53fa9d6842f5c4489d7eff924 Mon Sep 17 00:00:00 2001 From: Furquan Shaikh Date: Tue, 13 Dec 2016 09:43:46 -0800 Subject: [PATCH] acpi_device: Add special HID for DT namespace BUG=chrome-os-partner:60194 BRANCH=None TEST=Compiles successfully Change-Id: I0fe146cf2235c7c4ad3ea5589ed556884de3a368 Signed-off-by: Furquan Shaikh Reviewed-on: https://review.coreboot.org/17842 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel Reviewed-by: Duncan Laurie --- src/arch/x86/include/arch/acpi_device.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/src/arch/x86/include/arch/acpi_device.h b/src/arch/x86/include/arch/acpi_device.h index b0285d2c23..6e8f812fa0 100644 --- a/src/arch/x86/include/arch/acpi_device.h +++ b/src/arch/x86/include/arch/acpi_device.h @@ -24,6 +24,18 @@ #define ACPI_DESCRIPTOR_GPIO (ACPI_DESCRIPTOR_LARGE | 12) #define ACPI_DESCRIPTOR_SERIAL_BUS (ACPI_DESCRIPTOR_LARGE | 14) +/* + * PRP0001 is a special DT namespace link device ID. It provides a means to use + * existing DT-compatible device identification in ACPI. When this _HID is used + * by an ACPI device, the ACPI subsystem in OS looks up "compatible" property in + * device object's _DSD and will use the value of that property to identify the + * corresponding device in analogy with the original DT device identification + * algorithm. + * More details can be found in Linux kernel documentation: + * Documentation/acpi/enumeration.txt + */ +#define ACPI_DT_NAMESPACE_HID "PRP0001" + struct device; const char *acpi_device_name(struct device *dev); const char *acpi_device_path(struct device *dev);