Re: [PATCH v4 01/12] dt-bindings: i3c: Add mipi-i3c-static-method to support SETAASA

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 <[email protected]>
> ---

Reviewed-by: Frank Li <[email protected]>

>  .../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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