dt-bindings: can: sja1000: Convert to json-schema

Convert the NXP SJA1000 CAN Controller Device Tree binding
documentation to json-schema.

Update the example to match reality.

Link: https://lore.kernel.org/all/20220710115248.190280-2-biju.das.jz@bp.renesas.com
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Documentation/devicetree/bindings/net/can/nxp,sja1000.yaml

@@ -0,0 +1,101 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/can/nxp,sja1000.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Memory mapped SJA1000 CAN controller from NXP (formerly Philips)
+
+maintainers:
+  - Wolfgang Grandegger <wg@grandegger.com>
+
+properties:
+  compatible:
+    enum:
+      - nxp,sja1000
+      - technologic,sja1000
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  reg-io-width:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: I/O register width (in bytes) implemented by this device
+    default: 1
+    enum: [ 1, 2, 4 ]
+
+  nxp,external-clock-frequency:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    default: 16000000
+    description: |
+      Frequency of the external oscillator clock in Hz.
+      The internal clock frequency used by the SJA1000 is half of that value.
+
+  nxp,tx-output-mode:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    enum: [ 0, 1, 2, 3 ]
+    default: 1
+    description: |
+      operation mode of the TX output control logic. Valid values are:
+        <0> : bi-phase output mode
+        <1> : normal output mode (default)
+        <2> : test output mode
+        <3> : clock output mode
+
+  nxp,tx-output-config:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    default: 0x02
+    description: |
+      TX output pin configuration. Valid values are any one of the below
+      or combination of TX0 and TX1:
+        <0x01> : TX0 invert
+        <0x02> : TX0 pull-down (default)
+        <0x04> : TX0 pull-up
+        <0x06> : TX0 push-pull
+        <0x08> : TX1 invert
+        <0x10> : TX1 pull-down
+        <0x20> : TX1 pull-up
+        <0x30> : TX1 push-pull
+
+  nxp,clock-out-frequency:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: |
+      clock frequency in Hz on the CLKOUT pin.
+      If not specified or if the specified value is 0, the CLKOUT pin
+      will be disabled.
+
+  nxp,no-comparator-bypass:
+    type: boolean
+    description: Allows to disable the CAN input comparator.
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+allOf:
+  - $ref: can-controller.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: technologic,sja1000
+    then:
+      required:
+        - reg-io-width
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    can@1a000 {
+        compatible = "technologic,sja1000";
+        reg = <0x1a000 0x100>;
+        interrupts = <1>;
+        reg-io-width = <2>;
+        nxp,tx-output-config = <0x06>;
+        nxp,external-clock-frequency = <24000000>;
+    };