dt-bindings: serial: Convert Samsung UART bindings to json-schema

Convert Samsung S3C/S5P/Exynos Serial/UART bindings to DT schema format
using json-schema.

Signed-off-by: Krzysztof Kozlowski <[e-mail]>
Signed-off-by: Rob Herring <[e-mail]>

Documentation/devicetree/bindings/mfd/samsung,exynos5433-lpass.txt

···
 UART, SLIMBUS, PCM, I2S, DMAC, Timers 0...4, VIC, WDT 0...1 devices.
 
 Bindings of the sub-nodes are described in:
-  ../serial/samsung_uart.txt
+  ../serial/samsung_uart.yaml
   ../sound/samsung-i2s.txt
   ../dma/arm-pl330.txt
 

Documentation/devicetree/bindings/serial/samsung_uart.txt

···
-* Samsung's UART Controller
-
-The Samsung's UART controller is used for interfacing SoC with serial
-communicaion devices.
-
-Required properties:
-- compatible: should be one of following:
-  - "samsung,exynos4210-uart" -  Exynos4210 SoC,
-  - "samsung,s3c2410-uart" - compatible with ports present on S3C2410 SoC,
-  - "samsung,s3c2412-uart" - compatible with ports present on S3C2412 SoC,
-  - "samsung,s3c2440-uart" - compatible with ports present on S3C2440 SoC,
-  - "samsung,s3c6400-uart" - compatible with ports present on S3C6400 SoC,
-  - "samsung,s5pv210-uart" - compatible with ports present on S5PV210 SoC.
-
-- reg: base physical address of the controller and length of memory mapped
-  region.
-
-- interrupts: a single interrupt signal to SoC interrupt controller,
-  according to interrupt bindings documentation [1].
-
-- clock-names: input names of clocks used by the controller:
-  - "uart" - controller bus clock,
-  - "clk_uart_baudN" - Nth baud base clock input (N = 0, 1, ...),
-    according to SoC User's Manual (only N = 0 is allowedfor SoCs without
-    internal baud clock mux).
-- clocks: phandles and specifiers for all clocks specified in "clock-names"
-  property, in the same order, according to clock bindings documentation [2].
-
-[1] Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
-[2] Documentation/devicetree/bindings/clock/clock-bindings.txt
-
-Optional properties:
-- samsung,uart-fifosize: The fifo size supported by the UART channel
-
-Note: Each Samsung UART should have an alias correctly numbered in the
-"aliases" node, according to serialN format, where N is the port number
-(non-negative decimal integer) as specified by User's Manual of respective
-SoC.
-
-Example:
-	aliases {
-		serial0 = &uart0;
-		serial1 = &uart1;
-		serial2 = &uart2;
-	};
-
-Example:
-	uart1: serial@7f005400 {
-		compatible = "samsung,s3c6400-uart";
-		reg = <0x7f005400 0x100>;
-		interrupt-parent = <&vic1>;
-		interrupts = <6>;
-		clock-names = "uart", "clk_uart_baud2",
-				"clk_uart_baud3";
-		clocks = <&clocks PCLK_UART1>, <&clocks PCLK_UART1>,
-				<&clocks SCLK_UART>;
-		samsung,uart-fifosize = <16>;
-	};

Documentation/devicetree/bindings/serial/samsung_uart.yaml

···
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/serial/samsung_uart.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Samsung S3C, S5P and Exynos SoC UART Controller
+
+maintainers:
+  - Krzysztof Kozlowski <[e-mail]>
+  - Greg Kroah-Hartman <[e-mail]>
+
+description: |+
+  Each Samsung UART should have an alias correctly numbered in the "aliases"
+  node, according to serialN format, where N is the port number (non-negative
+  decimal integer) as specified by User's Manual of respective SoC.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - samsung,s3c2410-uart
+          - samsung,s3c2412-uart
+          - samsung,s3c2440-uart
+          - samsung,s3c6400-uart
+          - samsung,s5pv210-uart
+          - samsung,exynos4210-uart
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    minItems: 2
+    maxItems: 5
+
+  clock-names:
+    description: N = 0 is allowed for SoCs without internal baud clock mux.
+    minItems: 2
+    maxItems: 5
+    items:
+      - const: uart
+      - pattern: '^clk_uart_baud[0-3]$'
+      - pattern: '^clk_uart_baud[0-3]$'
+      - pattern: '^clk_uart_baud[0-3]$'
+      - pattern: '^clk_uart_baud[0-3]$'
+
+  interrupts:
+    description: RX interrupt and optionally TX interrupt.
+    minItems: 1
+    maxItems: 2
+
+  samsung,uart-fifosize:
+    description: The fifo size supported by the UART channel.
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint32
+      - enum: [16, 64, 256]
+
+required:
+  - compatible
+  - clocks
+  - clock-names
+  - interrupts
+  - reg
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - samsung,s3c2410-uart
+              - samsung,s5pv210-uart
+    then:
+      properties:
+        clocks:
+          minItems: 2
+          maxItems: 3
+        clock-names:
+          minItems: 2
+          maxItems: 3
+          items:
+            - const: uart
+            - pattern: '^clk_uart_baud[0-1]$'
+            - pattern: '^clk_uart_baud[0-1]$'
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - samsung,exynos4210-uart
+    then:
+      properties:
+        clocks:
+          minItems: 2
+          maxItems: 2
+        clock-names:
+          minItems: 2
+          maxItems: 2
+          items:
+            - const: uart
+            - const: clk_uart_baud0
+
+examples:
+  - |
+    #include <dt-bindings/clock/samsung,s3c64xx-clock.h>
+
+    uart0: serial@7f005000 {
+        compatible = "samsung,s3c6400-uart";
+        reg = <0x7f005000 0x100>;
+        interrupt-parent = <&vic1>;
+        interrupts = <5>;
+        clock-names = "uart", "clk_uart_baud2",
+                      "clk_uart_baud3";
+        clocks = <&clocks PCLK_UART0>, <&clocks PCLK_UART0>,
+                 <&clocks SCLK_UART>;
+        samsung,uart-fifosize = <16>;
+    };