[PATCH v8 1/5] dt-bindings: leds: Add Allwinner A100 LED controller

[Samuel Holland <samuel@sholland.org>]

The Allwinner A100, R329, and D1 SoCs contain an LED controller designed
to drive a series of RGB LED pixels. It supports PIO and DMA transfers,
and has configurable timing and pixel format. All three implementations
appear to be identical, so use the oldest as the fallback compatible.

Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Tested-by: Trevor Woerner <twoerner@gmail.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
---

Changes in v8:
 - Remove redundant "Bindings" from the binding document title
 - Make the DMA channel optional; the driver now works without DMA

Changes in v5:
 - A100 contains the original implementation, so use that as the base
   compatible string, and rename the binding to match
 - Add "unevaluatedProperties: false" to the child multi-led binding

Changes in v4:
 - Use "default" instead of "maxItems" for timing properties

Changes in v3:
 - Removed quotes from enumeration values
 - Added vendor prefix to timing/format properties
 - Renamed "format" property to "pixel-format" for clarity
 - Dropped "vled-supply" as it is unrelated to the controller hardware

Changes in v2:
 - Fixed typo leading to duplicate t1h-ns property
 - Removed "items" layer in definition of dmas/dma-names
 - Replaced uint32 type reference with maxItems in timing properties

 .../leds/allwinner,sun50i-a100-ledc.yaml      | 137 ++++++++++++++++++
 1 file changed, 137 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/allwinner,sun50i-a100-ledc.yaml

diff --git a/Documentation/devicetree/bindings/leds/allwinner,sun50i-a100-ledc.yaml b/Documentation/devicetree/bindings/leds/allwinner,sun50i-a100-ledc.yaml
new file mode 100644
index 000000000000..760cb336dccb
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/allwinner,sun50i-a100-ledc.yaml
@@ -0,0 +1,137 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/allwinner,sun50i-a100-ledc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner A100 LED Controller
+
+maintainers:
+  - Samuel Holland <samuel@sholland.org>
+
+description:
+  The LED controller found in Allwinner sunxi SoCs uses a one-wire serial
+  interface to drive up to 1024 RGB LEDs.
+
+properties:
+  compatible:
+    oneOf:
+      - const: allwinner,sun50i-a100-ledc
+      - items:
+          - enum:
+              - allwinner,sun20i-d1-ledc
+              - allwinner,sun50i-r329-ledc
+          - const: allwinner,sun50i-a100-ledc
+
+  reg:
+    maxItems: 1
+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: Bus clock
+      - description: Module clock
+
+  clock-names:
+    items:
+      - const: bus
+      - const: mod
+
+  resets:
+    maxItems: 1
+
+  dmas:
+    maxItems: 1
+    description: TX DMA channel
+
+  dma-names:
+    const: tx
+
+  allwinner,pixel-format:
+    description: Pixel format (subpixel transmission order), default is "grb"
+    enum:
+      - bgr
+      - brg
+      - gbr
+      - grb
+      - rbg
+      - rgb
+
+  allwinner,t0h-ns:
+    default: 336
+    description: Length of high pulse when transmitting a "0" bit
+
+  allwinner,t0l-ns:
+    default: 840
+    description: Length of low pulse when transmitting a "0" bit
+
+  allwinner,t1h-ns:
+    default: 882
+    description: Length of high pulse when transmitting a "1" bit
+
+  allwinner,t1l-ns:
+    default: 294
+    description: Length of low pulse when transmitting a "1" bit
+
+  allwinner,treset-ns:
+    default: 300000
+    description: Minimum delay between transmission frames
+
+patternProperties:
+  "^multi-led@[0-9a-f]+$":
+    type: object
+    $ref: leds-class-multicolor.yaml#
+    unevaluatedProperties: false
+    properties:
+      reg:
+        minimum: 0
+        maximum: 1023
+        description: Index of the LED in the series (must be contiguous)
+
+    required:
+      - reg
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+  - resets
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    #include <dt-bindings/leds/common.h>
+
+    ledc: led-controller@2008000 {
+      compatible = "allwinner,sun20i-d1-ledc",
+                   "allwinner,sun50i-a100-ledc";
+      reg = <0x2008000 0x400>;
+      interrupts = <36 IRQ_TYPE_LEVEL_HIGH>;
+      clocks = <&ccu 12>, <&ccu 34>;
+      clock-names = "bus", "mod";
+      resets = <&ccu 12>;
+      dmas = <&dma 42>;
+      dma-names = "tx";
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      multi-led@0 {
+        reg = <0x0>;
+        color = <LED_COLOR_ID_RGB>;
+        function = LED_FUNCTION_INDICATOR;
+      };
+    };
+
+...
-- 
2.41.0