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authorSakari Ailus <sakari.ailus@linux.intel.com>2018-07-17 17:19:20 +0300
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2018-07-23 13:44:52 +0300
commite49363e96fd2ee3fd5259fd2a6f9050cb4af82c8 (patch)
treee24108ac4945726978f4e94081ce3673effd5f84 /Documentation/acpi
parente58b1c6a9422b97b30838e77b7d1d2bbed121e96 (diff)
downloadlinux-e49363e96fd2ee3fd5259fd2a6f9050cb4af82c8.tar.xz
ACPI: property: graph: Improve graph documentation for port/ep numbering
Document that if a port has a single endpoint only, its value shall be zero. Similarly, if a device object only has a single port, its value shlla be zero. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'Documentation/acpi')
-rw-r--r--Documentation/acpi/dsd/graph.txt5
1 files changed, 4 insertions, 1 deletions
diff --git a/Documentation/acpi/dsd/graph.txt b/Documentation/acpi/dsd/graph.txt
index 0b007fceda0e..3131f457882b 100644
--- a/Documentation/acpi/dsd/graph.txt
+++ b/Documentation/acpi/dsd/graph.txt
@@ -55,7 +55,10 @@ endpoint. An example of such a package would be:
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 "endpoint". Port numbers must be unique within a
-device and endpoint numbers must be unique within a port.
+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 reference in the same package. Such references consist of the