[RFC PATCH v3 1/4] dt-bindings: net: can: add STM32 bxcan DT bindings

[Dario Binacchi]

Add documentation of device tree bindings for the STM32 basic extended
CAN (bxcan) controller.

Signed-off-by: Dario Binacchi <dario.binacchi at amarulasolutions.com>

---

Changes in v3:
- Remove 'Dario Binacchi <dariobin at libero.it>' SOB.
- Add description to the parent of the two child nodes.
- Move "patterProperties:" after "properties: in top level before "required".
- Add "clocks" to the "required:" list of the child nodes.

Changes in v2:
- Change the file name into 'st,stm32-bxcan-core.yaml'.
- Rename compatibles:
  - st,stm32-bxcan-core -> st,stm32f4-bxcan-core
  - st,stm32-bxcan -> st,stm32f4-bxcan
- Rename master property to st,can-master.
- Remove the status property from the example.
- Put the node child properties as required.

 .../bindings/net/can/st,stm32-bxcan.yaml      | 142 ++++++++++++++++++
 1 file changed, 142 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml

diff --git a/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
new file mode 100644
index 000000000000..3278c724e6f5
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
@@ -0,0 +1,142 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/can/st,stm32-bxcan.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: STMicroelectronics bxCAN controller
+
+description: STMicroelectronics BxCAN controller for CAN bus
+
+maintainers:
+  - Dario Binacchi <dario.binacchi at amarulasolutions.com>
+
+allOf:
+  - $ref: can-controller.yaml#
+
+properties:
+  compatible:
+    description:
+      It manages the access to the 512-bytes SRAM memory shared by the
+      two bxCAN cells (CAN1 master and CAN2 slave) in dual CAN peripheral
+      configuration.
+    enum:
+      - st,stm32f4-bxcan-core
+
+  reg:
+    maxItems: 1
+
+  resets:
+    maxItems: 1
+
+  clocks:
+    description:
+      Input clock for registers access
+    maxItems: 1
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+patternProperties:
+  "^can@[0-9]+$":
+    type: object
+    description:
+      A CAN block node contains two subnodes, representing each one a CAN
+      instance available on the machine.
+
+    properties:
+      compatible:
+        enum:
+          - st,stm32f4-bxcan
+
+      st,can-master:
+        description:
+          Master and slave mode of the bxCAN peripheral is only relevant
+          if the chip has two CAN peripherals. In that case they share
+          some of the required logic, and that means you cannot use the
+          slave CAN without the master CAN.
+        type: boolean
+
+      reg:
+        description: |
+          Offset of CAN instance in CAN block. Valid values are:
+            - 0x0:   CAN1
+            - 0x400: CAN2
+        maxItems: 1
+
+      interrupts:
+        items:
+          - description: transmit interrupt
+          - description: FIFO 0 receive interrupt
+          - description: FIFO 1 receive interrupt
+          - description: status change error interrupt
+
+      interrupt-names:
+        items:
+          - const: tx
+          - const: rx0
+          - const: rx1
+          - const: sce
+
+      resets:
+        maxItems: 1
+
+      clocks:
+        description:
+          Input clock for registers access
+        maxItems: 1
+
+    additionalProperties: false
+
+    required:
+      - compatible
+      - reg
+      - interrupts
+      - resets
+      - clocks
+
+required:
+  - compatible
+  - reg
+  - resets
+  - clocks
+  - '#address-cells'
+  - '#size-cells'
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/stm32fx-clock.h>
+    #include <dt-bindings/mfd/stm32f4-rcc.h>
+
+    can: can at 40006400 {
+        compatible = "st,stm32f4-bxcan-core";
+        reg = <0x40006400 0x800>;
+        resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
+        clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN1)>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        can1: can at 0 {
+            compatible = "st,stm32f4-bxcan";
+            reg = <0x0>;
+            interrupts = <19>, <20>, <21>, <22>;
+            interrupt-names = "tx", "rx0", "rx1", "sce";
+            resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
+            clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN1)>;
+            st,can-master;
+        };
+
+        can2: can at 400 {
+            compatible = "st,stm32f4-bxcan";
+            reg = <0x400>;
+            interrupts = <63>, <64>, <65>, <66>;
+            interrupt-names = "tx", "rx0", "rx1", "sce";
+            resets = <&rcc STM32F4_APB1_RESET(CAN2)>;
+            clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN2)>;
+        };
+    };
-- 
2.32.0