[PATCH v3 01/13] dt-bindings: i3c: Add mipi-i3c-static-method to support SETAASA

Akhil R
2026-04-23T08:58:32Z

Add the 'mipi-i3c-static-method' property mentioned in the MIPI I3C
Discovery and Configuration Specification [1] to specify which discovery
method an I3C device supports during bus initialization. The property is
a bitmap, where a bit value of 1 indicates support for that method, and 0
indicates lack of support.

Bit 0: SETDASA CCC (Direct)
Bit 1: SETAASA CCC (Broadcast)
Bit 2: Other CCC (vendor / standards extension)
All other bits are reserved.

It is specifically needed when an I3C device requires SETAASA for the
address assignment. SETDASA will be supported by default if this property
is absent, which means for now the property just serves as a flag to
enable SETAASA, but keep the property as a bitmap to align with the
specifications.

[1] https://www.mipi.org/mipi-disco-for-i3c-download

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
---
.../devicetree/bindings/i3c/i3c.yaml | 31 ++++++++++++++++---
include/dt-bindings/i3c/i3c.h | 3 ++
2 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/i3c/i3c.yaml b/Documentation/devicetree/bindings/i3c/i3c.yaml
index e25fa72fd785..225844abdd1f 100644
--- a/Documentation/devicetree/bindings/i3c/i3c.yaml
+++ b/Documentation/devicetree/bindings/i3c/i3c.yaml
@@ -31,10 +31,12 @@ properties:
described in the device tree, which in turn means we have to describe
I3C devices.

- Another use case for describing an I3C device in the device tree is when
- this I3C device has a static I2C address and we want to assign it a
- specific I3C dynamic address before the DAA takes place (so that other
- devices on the bus can't take this dynamic address).
+ Other use-cases for describing an I3C device in the device tree are:
+ - When the I3C device has a static I2C address and we want to assign
+ it a specific I3C dynamic address before the DAA takes place (so
+ that other devices on the bus can't take this dynamic address).
+ - When the I3C device requires SETAASA for its discovery and uses a
+ pre-defined static address.

"#size-cells":
const: 0
@@ -147,6 +149,27 @@ patternProperties:
through SETDASA. If static address is not present, this address is assigned
through SETNEWDA after assigning a temporary address via ENTDAA.

+ mipi-i3c-static-method:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ minimum: 0x1
+ maximum: 0x7
+ default: 1
+ description: |
+ Bitmap describing which methods of Dynamic Address Assignment from a
+ static address are supported by this I3C Target. A bit value of 1
+ indicates support for that method, and 0 indicates lack of support.
+
+ Bit 0: SETDASA CCC (Direct)
+ Bit 1: SETAASA CCC (Broadcast)
+ Bit 2: Other CCC (vendor / standards extension)
+ All other bits are reserved.
+
+ This property follows the MIPI I3C specification. The primary use
+ of this property is to indicate support for SETAASA, i.e Bit 1, but
+ will allow other values mentioned in the specification so that it
+ mirrors the specification. SETDASA will remain as the default method
+ even if this property is not present.
+
required:
- reg

diff --git a/include/dt-bindings/i3c/i3c.h b/include/dt-bindings/i3c/i3c.h
index 373439218bba..b4ceb9827ec0 100644
--- a/include/dt-bindings/i3c/i3c.h
+++ b/include/dt-bindings/i3c/i3c.h
@@ -13,4 +13,7 @@
#define I2C_NO_FILTER_HIGH_FREQUENCY (1 << 5)
#define I2C_NO_FILTER_LOW_FREQUENCY (2 << 5)

+#define I3C_ADDR_METHOD_SETDASA (1 << 0)
+#define I3C_ADDR_METHOD_SETAASA (1 << 1)
+
#endif
--
2.50.1