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Diffstat (limited to 'Documentation/devicetree/bindings/i2c/opencores,i2c-ocores.yaml')
-rw-r--r-- | Documentation/devicetree/bindings/i2c/opencores,i2c-ocores.yaml | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/i2c/opencores,i2c-ocores.yaml b/Documentation/devicetree/bindings/i2c/opencores,i2c-ocores.yaml new file mode 100644 index 0000000000..d9ef867290 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/opencores,i2c-ocores.yaml @@ -0,0 +1,114 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/i2c/opencores,i2c-ocores.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: OpenCores I2C controller + +maintainers: + - Peter Korsgaard <peter@korsgaard.com> + - Andrew Lunn <andrew@lunn.ch> + +allOf: + - $ref: /schemas/i2c/i2c-controller.yaml# + +properties: + compatible: + oneOf: + - items: + - enum: + - sifive,fu740-c000-i2c # Opencore based IP block FU740-C000 SoC + - sifive,fu540-c000-i2c # Opencore based IP block FU540-C000 SoC + - const: sifive,i2c0 + - enum: + - opencores,i2c-ocores + - aeroflexgaisler,i2cmst + + reg: + maxItems: 1 + + interrupts: + maxItems: 1 + + clocks: + maxItems: 1 + + clock-frequency: + description: | + clock-frequency property is meant to control the bus frequency for i2c bus + drivers, but it was incorrectly used to specify i2c controller input clock + frequency. So the following rules are set to fix this situation: + - if clock-frequency is present and neither opencores,ip-clock-frequency nor + clocks are, then clock-frequency specifies i2c controller clock frequency. + This is to keep backwards compatibility with setups using old DTB. i2c bus + frequency is fixed at 100 KHz. + - if clocks is present it specifies i2c controller clock. clock-frequency + property specifies i2c bus frequency. + - if opencores,ip-clock-frequency is present it specifies i2c controller + clock frequency. clock-frequency property specifies i2c bus frequency. + default: 100000 + + reg-io-width: + description: | + io register width in bytes + enum: [1, 2, 4] + + reg-shift: + description: | + device register offsets are shifted by this value + default: 0 + + regstep: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + deprecated, use reg-shift above + deprecated: true + + opencores,ip-clock-frequency: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Frequency of the controller clock in Hz. Mutually exclusive with clocks. + See the note above. + +required: + - compatible + - reg + - "#address-cells" + - "#size-cells" + +oneOf: + - required: + - opencores,ip-clock-frequency + - required: + - clocks + +unevaluatedProperties: false + +examples: + - | + i2c@a0000000 { + compatible = "opencores,i2c-ocores"; + reg = <0xa0000000 0x8>; + #address-cells = <1>; + #size-cells = <0>; + interrupts = <10>; + opencores,ip-clock-frequency = <20000000>; + + reg-shift = <0>; /* 8 bit registers */ + reg-io-width = <1>; /* 8 bit read/write */ + }; + + i2c@b0000000 { + compatible = "opencores,i2c-ocores"; + reg = <0xa0000000 0x8>; + #address-cells = <1>; + #size-cells = <0>; + interrupts = <10>; + clocks = <&osc>; + clock-frequency = <400000>; /* i2c bus frequency 400 KHz */ + + reg-shift = <0>; /* 8 bit registers */ + reg-io-width = <1>; /* 8 bit read/write */ + }; +... |