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Subject[PATCH v3] Documentation: acpi: Add an example for PRP0001
Date
Add an example for the magic PRP0001 device ID which allows matching
ACPI devices against drivers using OF Device Tree compatible property.

Signed-off-by: Thomas Preston <thomas.preston@codethink.co.uk>
---
Documentation/acpi/enumeration.txt | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/Documentation/acpi/enumeration.txt b/Documentation/acpi/enumeration.txt
index 7bcf9c3d9fbe..1395b844649c 100644
--- a/Documentation/acpi/enumeration.txt
+++ b/Documentation/acpi/enumeration.txt
@@ -410,6 +410,32 @@ Specifically, the device IDs returned by _HID and preceding PRP0001 in the _CID
return package will be checked first. Also in that case the bus type the device
will be enumerated to depends on the device ID returned by _HID.

+For example, the following ACPI sample might be used to enumerate an lm75-type
+I2C temperature sensor and match it to the driver using the Device Tree
+namespace link:
+
+ Device (TMP0)
+ {
+ Name (_HID, "PRP0001")
+ Name (_DSD, Package() {
+ ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
+ Package () {
+ Package (2) { "compatible", "ti,tmp75" },
+ }
+ })
+ Method (_CRS, 0, Serialized)
+ {
+ Name (SBUF, ResourceTemplate ()
+ {
+ I2cSerialBusV2 (0x48, ControllerInitiated,
+ 400000, AddressingMode7Bit,
+ "\\_SB.PCI0.I2C1", 0x00,
+ ResourceConsumer, , Exclusive,)
+ })
+ Return (SBUF)
+ }
+ }
+
It is valid to define device objects with a _HID returning PRP0001 and without
the "compatible" property in the _DSD or a _CID as long as one of their
ancestors provides a _DSD with a valid "compatible" property. Such device
--
2.11.0
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