[PATCH v2 2/6] dt-bindings: spi: Document Renesas SPIBSC bindings

[Chris Brandt <chris.brandt@xxxxxxxxxxx>]

Document the bindings used by the Renesas SPI bus space controller.

Signed-off-by: Chris Brandt <chris.brandt@xxxxxxxxxxx>
---
v2:
 * change to YAML format
 * add interrupts property
 * Used more terms directly from the hardware manual
---
 .../bindings/spi/renesas,spibsc.yaml          | 115 ++++++++++++++++++
 1 file changed, 115 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/spi/renesas,spibsc.yaml

diff --git a/Documentation/devicetree/bindings/spi/renesas,spibsc.yaml b/Documentation/devicetree/bindings/spi/renesas,spibsc.yaml
new file mode 100644
index 000000000000..afbdc0824cc6
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/renesas,spibsc.yaml
@@ -0,0 +1,115 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/renesas,spibsc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Renesas SPI Bus Space Controller (SPIBSC) Device Tree Bindings
+
+description: |
+  Otherwise referred to as the "SPI Multi I/O Bus Controller" in SoC hardware
+  manuals. This controller was designed specifically for accessing Serial flash
+  devices such as SPI Flash, HyperFlash and OctaFlash. The HW can operate in two
+  modes. One mode allows for normal byte by byte access (refereed to as
+  "Manual Mode"). The other mode allows for direct memory mapped access (read
+  only) to the flash area by the CPU (refereed to as "External Address Space
+  Read Mode").
+
+allOf:
+  - $ref: spi-controller.yaml#
+
+maintainers:
+  - Chris Brandt <chris.brandt@xxxxxxxxxxx>
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - enum:
+              - renesas,r7s72100-spibsc     # RZ/A1
+              - renesas,r7s9210-spibsc      # RZ/A2
+
+  reg:
+    minItems: 2
+    maxItems: 2
+    items:
+      - description: Registers
+      - description: Memory Mapped Address Space
+
+  interrupts:
+    description: Some HW versions do not contain interrupts
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  flash:
+    description: |
+      (Optional) In order to use the HW for R/W access ("Manual Mode"), a "flash"
+      subnode must be present with a "compatible" property that contains
+      "jedec,spi-nor". If a spi-nor property is not found, the HW is assumed to be
+      already operating in "External Address Space Read Mode".
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - '#address-cells'
+  - '#size-cells'
+
+examples:
+  - |
+    # This example is for "Manual Mode"
+    spibsc: spi@1f800000 {
+        compatible = "renesas,r7s9210-spibsc";
+        reg = <0x1f800000 0x100>, <0x20000000 0x10000000>;
+        clocks = <&cpg CPG_MOD 83>;
+        power-domains = <&cpg>;
+        interrupts = <GIC_SPI 445 IRQ_TYPE_LEVEL_HIGH>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        flash@0 {
+            compatible = "jedec,spi-nor";
+            reg = <0>;
+            spi-max-frequency = <40000000>;
+
+            partitions {
+                compatible = "fixed-partitions";
+                #address-cells = <1>;
+                #size-cells = <1>;
+
+                partition@0000000 {
+                    label = "u-boot";
+                    reg = <0x00000000 0x80000>;
+                };
+            };
+        };
+
+    # This example is for "External Address Space Read Mode"
+    spibsc: spi@1f800000 {
+        compatible = "renesas,r7s9210-spibsc";
+        reg = <0x1f800000 0x100>, <0x20000000 0x10000000>;
+        clocks = <&cpg CPG_MOD 83>;
+        power-domains = <&cpg>;
+        interrupts = <GIC_SPI 445 IRQ_TYPE_LEVEL_HIGH>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+    };
+    flash@20000000 {
+        compatible = "mtd-rom";
+        probe-type = "direct-mapped";
+        reg = <0x20000000 0x4000000>;
+        bank-width = <4>;
+        device-width = <1>;
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        partition@80000 {
+            label ="uboot_env";
+            reg = <0x00080000 0x010000>;
+            read-only;
+        };
+    };
+
+...
-- 
2.23.0