[PATCH V4] dt-bindings: mtd: brcm, brcmnand: convert to the json-schema

["Rafał Miłecki" <zajec5@gmail.com>]

From: Rafał Miłecki <rafal@milecki.pl>

This helps validating DTS files.

Changes that require mentioning:
1. Property "clock" was renamed to "clocks"
2. Duplicated properties (defined in nand-controller.yaml) were dropped
3. Compatible "brcm,nand-bcm63168" was added
4. SoC specific "compatible" cases got limited controller versions

Examples changes:
1. Nodes "nand" were renamed to "nand-controller"
2. Nodes "nandcs" were renamed to "nand"
3. Dropped partitions as they were using old syntax and are well
   documented elsewhere anyway

This rewritten binding validates cleanly using the "dt_binding_check".
Some Linux stored DTS files will require updating to make "dtbs_check"
happy.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Brian Norris <computersforpeace@gmail.com>
---
V2: Drop example partitions that were using deprecated syntax-thanks Rob
V3: "SoC specific "compatible" cases got limited controller versions"
    Thanks Rob for teaching me the items: enum [] trick (no "-")
V4: Fix reg-names for the brcm,nand-bcm6368 & brcm,nand-iproc (minItems)
    Thanks Brian!
---
 .../devicetree/bindings/mtd/brcm,brcmnand.txt | 186 --------------
 .../bindings/mtd/brcm,brcmnand.yaml           | 242 ++++++++++++++++++
 2 files changed, 242 insertions(+), 186 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt
 create mode 100644 Documentation/devicetree/bindings/mtd/brcm,brcmnand.yaml

diff --git a/Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt b/Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt
deleted file mode 100644
index 44335a4f8bfb..000000000000
--- a/Documentation/devicetree/bindings/mtd/brcm,brcmnand.txt
+++ /dev/null
@@ -1,186 +0,0 @@
-* Broadcom STB NAND Controller
-
-The Broadcom Set-Top Box NAND controller supports low-level access to raw NAND
-flash chips. It has a memory-mapped register interface for both control
-registers and for its data input/output buffer. On some SoCs, this controller is
-paired with a custom DMA engine (inventively named "Flash DMA") which supports
-basic PROGRAM and READ functions, among other features.
-
-This controller was originally designed for STB SoCs (BCM7xxx) but is now
-available on a variety of Broadcom SoCs, including some BCM3xxx, BCM63xx, and
-iProc/Cygnus. Its history includes several similar (but not fully register
-compatible) versions.
-
-Required properties:
-- compatible       : May contain an SoC-specific compatibility string (see below)
-                     to account for any SoC-specific hardware bits that may be
-                     added on top of the base core controller.
-                     In addition, must contain compatibility information about
-                     the core NAND controller, of the following form:
-                     "brcm,brcmnand" and an appropriate version compatibility
-                     string, like "brcm,brcmnand-v7.0"
-                     Possible values:
-                         brcm,brcmnand-v2.1
-                         brcm,brcmnand-v2.2
-                         brcm,brcmnand-v4.0
-                         brcm,brcmnand-v5.0
-                         brcm,brcmnand-v6.0
-                         brcm,brcmnand-v6.1
-                         brcm,brcmnand-v6.2
-                         brcm,brcmnand-v7.0
-                         brcm,brcmnand-v7.1
-                         brcm,brcmnand-v7.2
-                         brcm,brcmnand-v7.3
-                         brcm,brcmnand
-- reg              : the register start and length for NAND register region.
-                     (optional) Flash DMA register range (if present)
-                     (optional) NAND flash cache range (if at non-standard offset)
-- reg-names        : a list of the names corresponding to the previous register
-                     ranges. Should contain "nand" and (optionally)
-                     "flash-dma" or "flash-edu" and/or "nand-cache".
-- interrupts       : The NAND CTLRDY interrupt, (if Flash DMA is available)
-                     FLASH_DMA_DONE and if EDU is avaialble and used FLASH_EDU_DONE
-- interrupt-names  : May be "nand_ctlrdy" or "flash_dma_done" or "flash_edu_done",
-                     if broken out as individual interrupts.
-                     May be "nand", if the SoC has the individual NAND
-                     interrupts multiplexed behind another custom piece of
-                     hardware
-- #address-cells   : <1> - subnodes give the chip-select number
-- #size-cells      : <0>
-
-Optional properties:
-- clock                     : reference to the clock for the NAND controller
-- clock-names               : "nand" (required for the above clock)
-- brcm,nand-has-wp          : Some versions of this IP include a write-protect
-                              (WP) control bit. It is always available on >=
-                              v7.0. Use this property to describe the rare
-                              earlier versions of this core that include WP
-
- -- Additional SoC-specific NAND controller properties --
-
-The NAND controller is integrated differently on the variety of SoCs on which it
-is found. Part of this integration involves providing status and enable bits
-with which to control the 8 exposed NAND interrupts, as well as hardware for
-configuring the endianness of the data bus. On some SoCs, these features are
-handled via standard, modular components (e.g., their interrupts look like a
-normal IRQ chip), but on others, they are controlled in unique and interesting
-ways, sometimes with registers that lump multiple NAND-related functions
-together. The former case can be described simply by the standard interrupts
-properties in the main controller node. But for the latter exceptional cases,
-we define additional 'compatible' properties and associated register resources within the NAND controller node above.
-
- - compatible: Can be one of several SoC-specific strings. Each SoC may have
-   different requirements for its additional properties, as described below each
-   bullet point below.
-
-   * "brcm,nand-bcm63138"
-     - reg: (required) the 'NAND_INT_BASE' register range, with separate status
-       and enable registers
-     - reg-names: (required) "nand-int-base"
-
-   * "brcm,nand-bcm6368"
-     - compatible: should contain "brcm,nand-bcm<soc>", "brcm,nand-bcm6368"
-     - reg: (required) the 'NAND_INTR_BASE' register range, with combined status
-       and enable registers, and boot address registers
-     - reg-names: (required) "nand-int-base"
-
-   * "brcm,nand-iproc"
-     - reg: (required) the "IDM" register range, for interrupt enable and APB
-       bus access endianness configuration, and the "EXT" register range,
-       for interrupt status/ack.
-     - reg-names: (required) a list of the names corresponding to the previous
-       register ranges. Should contain "iproc-idm" and "iproc-ext".
-
-
-* NAND chip-select
-
-Each controller (compatible: "brcm,brcmnand") may contain one or more subnodes
-to represent enabled chip-selects which (may) contain NAND flash chips. Their
-properties are as follows.
-
-Required properties:
-- compatible                : should contain "brcm,nandcs"
-- reg                       : a single integer representing the chip-select
-                              number (e.g., 0, 1, 2, etc.)
-- #address-cells            : see partition.txt
-- #size-cells               : see partition.txt
-
-Optional properties:
-- nand-ecc-strength         : see nand-controller.yaml
-- nand-ecc-step-size        : must be 512 or 1024. See nand-controller.yaml
-- nand-on-flash-bbt         : boolean, to enable the on-flash BBT for this
-                              chip-select. See nand-controller.yaml
-- brcm,nand-oob-sector-size : integer, to denote the spare area sector size
-                              expected for the ECC layout in use. This size, in
-                              addition to the strength and step-size,
-                              determines how the hardware BCH engine will lay
-                              out the parity bytes it stores on the flash.
-                              This property can be automatically determined by
-                              the flash geometry (particularly the NAND page
-                              and OOB size) in many cases, but when booting
-                              from NAND, the boot controller has only a limited
-                              number of available options for its default ECC
-                              layout.
-
-Each nandcs device node may optionally contain sub-nodes describing the flash
-partition mapping. See partition.txt for more detail.
-
-
-Example:
-
-nand@f0442800 {
-	compatible = "brcm,brcmnand-v7.0", "brcm,brcmnand";
-	reg = <0xF0442800 0x600>,
-	      <0xF0443000 0x100>;
-	reg-names = "nand", "flash-dma";
-	interrupt-parent = <&hif_intr2_intc>;
-	interrupts = <24>, <4>;
-
-	#address-cells = <1>;
-	#size-cells = <0>;
-
-	nandcs@1 {
-		compatible = "brcm,nandcs";
-		reg = <1>; // Chip select 1
-		nand-on-flash-bbt;
-		nand-ecc-strength = <12>;
-		nand-ecc-step-size = <512>;
-
-		// Partitions
-		#address-cells = <1>;  // <2>, for 64-bit offset
-		#size-cells = <1>;     // <2>, for 64-bit length
-		flash0.rootfs@0 {
-			reg = <0 0x10000000>;
-		};
-		flash0@0 {
-			reg = <0 0>; // MTDPART_SIZ_FULL
-		};
-		flash0.kernel@10000000 {
-			reg = <0x10000000 0x400000>;
-		};
-	};
-};
-
-nand@10000200 {
-	compatible = "brcm,nand-bcm63168", "brcm,nand-bcm6368",
-		"brcm,brcmnand-v4.0", "brcm,brcmnand";
-	reg = <0x10000200 0x180>,
-	      <0x10000600 0x200>,
-	      <0x100000b0 0x10>;
-	reg-names = "nand", "nand-cache", "nand-int-base";
-	interrupt-parent = <&periph_intc>;
-	interrupts = <50>;
-	clocks = <&periph_clk 20>;
-	clock-names = "nand";
-
-	#address-cells = <1>;
-	#size-cells = <0>;
-
-	nand0: nandcs@0 {
-		compatible = "brcm,nandcs";
-		reg = <0>;
-		nand-on-flash-bbt;
-		nand-ecc-strength = <1>;
-		nand-ecc-step-size = <512>;
-	};
-};
diff --git a/Documentation/devicetree/bindings/mtd/brcm,brcmnand.yaml b/Documentation/devicetree/bindings/mtd/brcm,brcmnand.yaml
new file mode 100644
index 000000000000..e5f1a33332a5
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/brcm,brcmnand.yaml
@@ -0,0 +1,242 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mtd/brcm,brcmnand.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom STB NAND Controller
+
+maintainers:
+  - Brian Norris <computersforpeace@gmail.com>
+  - Kamal Dasu <kdasu.kdev@gmail.com>
+
+description: |
+  The Broadcom Set-Top Box NAND controller supports low-level access to raw NAND
+  flash chips. It has a memory-mapped register interface for both control
+  registers and for its data input/output buffer. On some SoCs, this controller
+  is paired with a custom DMA engine (inventively named "Flash DMA") which
+  supports basic PROGRAM and READ functions, among other features.
+
+  This controller was originally designed for STB SoCs (BCM7xxx) but is now
+  available on a variety of Broadcom SoCs, including some BCM3xxx, BCM63xx, and
+  iProc/Cygnus. Its history includes several similar (but not fully register
+  compatible) versions.
+
+  -- Additional SoC-specific NAND controller properties --
+
+  The NAND controller is integrated differently on the variety of SoCs on which
+  it is found. Part of this integration involves providing status and enable
+  bits with which to control the 8 exposed NAND interrupts, as well as hardware
+  for configuring the endianness of the data bus. On some SoCs, these features
+  are handled via standard, modular components (e.g., their interrupts look like
+  a normal IRQ chip), but on others, they are controlled in unique and
+  interesting ways, sometimes with registers that lump multiple NAND-related
+  functions together. The former case can be described simply by the standard
+  interrupts properties in the main controller node. But for the latter
+  exceptional cases, we define additional 'compatible' properties and associated
+  register resources within the NAND controller node above.
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - enum:
+              - brcm,brcmnand-v2.1
+              - brcm,brcmnand-v2.2
+              - brcm,brcmnand-v4.0
+              - brcm,brcmnand-v5.0
+              - brcm,brcmnand-v6.0
+              - brcm,brcmnand-v6.1
+              - brcm,brcmnand-v6.2
+              - brcm,brcmnand-v7.0
+              - brcm,brcmnand-v7.1
+              - brcm,brcmnand-v7.2
+              - brcm,brcmnand-v7.3
+          - const: brcm,brcmnand
+      - description: BCM63138 SoC-specific NAND controller
+        items:
+          - const: brcm,nand-bcm63138
+          - enum:
+              - brcm,brcmnand-v7.0
+              - brcm,brcmnand-v7.1
+          - const: brcm,brcmnand
+      - description: iProc SoC-specific NAND controller
+        items:
+          - const: brcm,nand-iproc
+          - const: brcm,brcmnand-v6.1
+          - const: brcm,brcmnand
+      - description: BCM63168 SoC-specific NAND controller
+        items:
+          - const: brcm,nand-bcm63168
+          - const: brcm,nand-bcm6368
+          - const: brcm,brcmnand-v4.0
+          - const: brcm,brcmnand
+
+  reg:
+    minItems: 1
+    maxItems: 6
+
+  reg-names:
+    minItems: 1
+    maxItems: 6
+    items:
+      enum: [ nand, flash-dma, flash-edu, nand-cache, nand-int-base, iproc-idm, iproc-ext ]
+
+  interrupts:
+    minItems: 1
+    maxItems: 3
+    items:
+      - description: NAND CTLRDY interrupt
+      - description: FLASH_DMA_DONE if flash DMA is available
+      - description: FLASH_EDU_DONE if EDU is available
+
+  interrupt-names:
+    minItems: 1
+    maxItems: 3
+    items:
+      - const: nand_ctlrdy
+      - const: flash_dma_done
+      - const: flash_edu_done
+
+  clocks:
+    maxItems: 1
+    description: reference to the clock for the NAND controller
+
+  clock-names:
+    const: nand
+
+  brcm,nand-has-wp:
+    description: >
+      Some versions of this IP include a write-protect
+      (WP) control bit. It is always available on >=
+      v7.0. Use this property to describe the rare
+      earlier versions of this core that include WP
+    type: boolean
+
+patternProperties:
+  "^nand@[a-f0-9]$":
+    type: object
+    properties:
+      compatible:
+        const: brcm,nandcs
+
+      nand-ecc-step-size:
+        enum: [ 512, 1024 ]
+
+      brcm,nand-oob-sector-size:
+        description: |
+          integer, to denote the spare area sector size
+          expected for the ECC layout in use. This size, in
+          addition to the strength and step-size,
+          determines how the hardware BCH engine will lay
+          out the parity bytes it stores on the flash.
+          This property can be automatically determined by
+          the flash geometry (particularly the NAND page
+          and OOB size) in many cases, but when booting
+          from NAND, the boot controller has only a limited
+          number of available options for its default ECC
+          layout.
+        $ref: /schemas/types.yaml#/definitions/uint32
+
+allOf:
+  - $ref: nand-controller.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: brcm,nand-bcm63138
+    then:
+      properties:
+        reg-names:
+          minItems: 2
+          maxItems: 2
+          items:
+            - const: nand
+            - const: nand-int-base
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: brcm,nand-bcm6368
+    then:
+      properties:
+        reg-names:
+          minItems: 3
+          maxItems: 3
+          items:
+            - const: nand
+            - const: nand-int-base
+            - const: nand-cache
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: brcm,nand-iproc
+    then:
+      properties:
+        reg-names:
+          minItems: 3
+          maxItems: 3
+          items:
+            - const: nand
+            - const: iproc-idm
+            - const: iproc-ext
+
+unevaluatedProperties: false
+
+required:
+  - reg
+  - reg-names
+  - interrupts
+
+examples:
+  - |
+    nand-controller@f0442800 {
+            compatible = "brcm,brcmnand-v7.0", "brcm,brcmnand";
+            reg = <0xf0442800 0x600>,
+                  <0xf0443000 0x100>;
+            reg-names = "nand", "flash-dma";
+            interrupt-parent = <&hif_intr2_intc>;
+            interrupts = <24>, <4>;
+
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            nand@1 {
+                    compatible = "brcm,nandcs";
+                    reg = <1>; // Chip select 1
+                    nand-on-flash-bbt;
+                    nand-ecc-strength = <12>;
+                    nand-ecc-step-size = <512>;
+
+                    #address-cells = <1>;
+                    #size-cells = <1>;
+            };
+    };
+  - |
+    nand-controller@10000200 {
+            compatible = "brcm,nand-bcm63168", "brcm,nand-bcm6368",
+                         "brcm,brcmnand-v4.0", "brcm,brcmnand";
+            reg = <0x10000200 0x180>,
+                  <0x100000b0 0x10>,
+                  <0x10000600 0x200>;
+            reg-names = "nand", "nand-int-base", "nand-cache";
+            interrupt-parent = <&periph_intc>;
+            interrupts = <50>;
+            clocks = <&periph_clk 20>;
+            clock-names = "nand";
+
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            nand@0 {
+                    compatible = "brcm,nandcs";
+                    reg = <0>;
+                    nand-on-flash-bbt;
+                    nand-ecc-strength = <1>;
+                    nand-ecc-step-size = <512>;
+
+                    #address-cells = <1>;
+                    #size-cells = <1>;
+            };
+    };
-- 
2.26.2