Documentation/firmware-guide/acpi/dsd/graph.rst

Source file repositories/reference/linux-study-clean/Documentation/firmware-guide/acpi/dsd/graph.rst

File Facts

System
Linux kernel
Corpus path
Documentation/firmware-guide/acpi/dsd/graph.rst
Extension
.rst
Size
5686 bytes
Lines
171
Domain
Support Tooling And Documentation
Bucket
Documentation
Inferred role
Support Tooling And Documentation: documentation
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

Package() { "port@4", "PRT4" }

Further on, endpoints are located under the port nodes. The hierarchical
data extension key of the endpoint nodes must begin with
"endpoint" and must be followed by the "@" character and the number of the
endpoint. The object it refers to should be called "EPXY", where "X" is the
number of the port and "Y" is the number of the endpoint. An example of such a
package would be::

    Package() { "endpoint@0", "EP40" }

Each port node contains a property extension key "port", the value of which is
the number of the port. Each endpoint is similarly numbered with a property
extension key "reg", the value of which is the number of the endpoint. Port
numbers must be unique within a device and endpoint numbers must be unique
within a port. If a device object may only has a single port, then the number
of that port shall be zero. Similarly, if a port may only have a single
endpoint, the number of that endpoint shall be zero.

The endpoint reference uses property extension with "remote-endpoint" property
name followed by a string reference in the same package. [data-node-ref]::

    "device.datanode"

In the above example, "X" is the number of the port and "Y" is the number of
the endpoint.

The references to endpoints must be always done both ways, to the
remote endpoint and back from the referred remote endpoint node.

A simple example of this is show below::

    Scope (\_SB.PCI0.I2C2)
    {
	Device (CAM0)
	{
	    Name (_DSD, Package () {
		ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
		Package () {
		    Package () { "compatible", Package () { "nokia,smia" } },
		},
		ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
		Package () {
		    Package () { "port@0", "PRT0" },
		}
	    })
	    Name (PRT0, Package() {
		ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
		Package () {
		    Package () { "reg", 0 },
		},
		ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
		Package () {
		    Package () { "endpoint@0", "EP00" },
		}
	    })
	    Name (EP00, Package() {
		ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
		Package () {
		    Package () { "reg", 0 },
		    Package () { "remote-endpoint", "\\_SB.PCI0.ISP.EP40" },
		}
	    })
	}
    }

    Scope (\_SB.PCI0)
    {
	Device (ISP)
	{

Annotation

Implementation Notes