[PATCH v21 1/4] dt-bindings: i2c: Split AST2600 binding into a new YAML

Ryan Chen
2025-10-27T06:12:54Z

The AST2600 I2C controller introduces a completely new register
map and Separate control/target register sets, unlike the mixed
layout used in AST2400/AST2500.

In addition, at new AST2600 configuration registers and transfer
modes require new DT properties, which are incompatible with
existing bindings. Therefore, this patch creates a dedicated
binding file for AST2600 to properly describe these new
hardware capabilities.

A subsequent change will modify this new binding to properly
describe the AST2600 hardware.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
---
.../devicetree/bindings/i2c/aspeed,i2c.yaml | 3 +-
.../devicetree/bindings/i2c/ast2600-i2c.yaml | 66 +++++++++++++++++++
2 files changed, 67 insertions(+), 2 deletions(-)
create mode 100644 Documentation/devicetree/bindings/i2c/ast2600-i2c.yaml

diff --git a/Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml b/Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml
index 5b9bd2feda3b..d4e4f412feba 100644
--- a/Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml
+++ b/Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml
@@ -4,7 +4,7 @@
$id: http://devicetree.org/schemas/i2c/aspeed,i2c.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

-title: ASPEED I2C on the AST24XX, AST25XX, and AST26XX SoCs
+title: ASPEED I2C on the AST24XX, AST25XX SoCs

maintainers:
- Rayn Chen <rayn_chen@aspeedtech.com>
@@ -17,7 +17,6 @@ properties:
enum:
- aspeed,ast2400-i2c-bus
- aspeed,ast2500-i2c-bus
- - aspeed,ast2600-i2c-bus

reg:
minItems: 1
diff --git a/Documentation/devicetree/bindings/i2c/ast2600-i2c.yaml b/Documentation/devicetree/bindings/i2c/ast2600-i2c.yaml
new file mode 100644
index 000000000000..6ddcec5decdc
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/ast2600-i2c.yaml
@@ -0,0 +1,66 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/ast2600-i2c.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ASPEED I2C on the AST26XX SoCs
+
+maintainers:
+ - Ryan Chen <ryan_chen@aspeedtech.com>
+
+allOf:
+ - $ref: /schemas/i2c/i2c-controller.yaml#
+
+properties:
+ compatible:
+ enum:
+ - aspeed,ast2600-i2c-bus
+
+ reg:
+ minItems: 1
+ items:
+ - description: address offset and range of bus
+ - description: address offset and range of bus buffer
+
+ interrupts:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+ description:
+ root clock of bus, should reference the APB
+ clock in the second cell
+
+ resets:
+ maxItems: 1
+
+ bus-frequency:
+ minimum: 500
+ maximum: 4000000
+ default: 100000
+ description: frequency of the bus clock in Hz defaults to 100 kHz when not
+ specified
+
+required:
+ - reg
+ - compatible
+ - clocks
+ - resets
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/clock/aspeed-clock.h>
+ i2c@40 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "aspeed,ast2600-i2c-bus";
+ reg = <0x40 0x40>;
+ clocks = <&syscon ASPEED_CLK_APB>;
+ resets = <&syscon ASPEED_RESET_I2C>;
+ bus-frequency = <100000>;
+ interrupts = <0>;
+ interrupt-parent = <&i2c_ic>;
+ };
--
2.34.1