[PATCH v4 01/12] dt-bindings: i3c: Add mipi-i3c-static-method to support SETAASA
Frank Li
Frank.li at oss.nxp.com
Thu Jun 18 12:35:34 PDT 2026
On Tue, Jun 16, 2026 at 09:54:15AM +0000, Akhil R wrote:
> 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 at nvidia.com>
> ---
Reviewed-by: Frank Li <Frank.Li at nxp.com>
> .../devicetree/bindings/i3c/i3c.yaml | 36 ++++++++++++++++---
> include/dt-bindings/i3c/i3c.h | 4 +++
> 2 files changed, 35 insertions(+), 5 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/i3c/i3c.yaml b/Documentation/devicetree/bindings/i3c/i3c.yaml
> index e25fa72fd785..5603f2e7807d 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
> @@ -145,7 +147,31 @@ patternProperties:
> Dynamic address to be assigned to this device. In case static address is
> present (first cell of the reg property != 0), this address is assigned
> through SETDASA. If static address is not present, this address is assigned
> - through SETNEWDA after assigning a temporary address via ENTDAA.
> + through SETNEWDA after assigning a temporary address via ENTDAA. If
> + SETAASA is used, this property is not used, and the static address itself
> + becomes the dynamic address.
> +
> + 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. For each defined bit
> + position, a set bit indicates support for that method and a cleared
> + bit 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..78b8c634aad8 100644
> --- a/include/dt-bindings/i3c/i3c.h
> +++ b/include/dt-bindings/i3c/i3c.h
> @@ -13,4 +13,8 @@
> #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)
> +#define I3C_ADDR_METHOD_VENDOR (1 << 2)
> +
> #endif
> --
> 2.43.0
>
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