Re: [PATCH v22 17/18] dt-bindings: mtd: pl353-nand: Describe this hardware controller

On 09/06/2021 15:36, Miquel Raynal wrote:

Hi Krzysztof,

Krzysztof Kozlowski [off-list ref] wrote on Wed, 9
Jun 2021 14:01:10 +0200:

quoted

On 09/06/2021 10:01, Miquel Raynal wrote:

quoted

Add a yaml description of this NAND controller which is described as a
subnode of the SMC bus.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 .../bindings/mtd/arm,pl353-nand-r2p1.yaml     | 57 +++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mtd/arm,pl353-nand-r2p1.yaml

diff --git a/Documentation/devicetree/bindings/mtd/arm,pl353-nand-r2p1.yaml b/Documentation/devicetree/bindings/mtd/arm,pl353-nand-r2p1.yaml
new file mode 100644
index 000000000000..e72fa14b4385
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/arm,pl353-nand-r2p1.yaml

@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mtd/arm,pl353-nand-r2p1.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: PL353 NAND Controller device tree bindings
+
+allOf:
+  - $ref: "nand-controller.yaml"
+
+maintainers:
+  - Miquel Raynal <miquel.raynal@bootlin.com>
+  - Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
+
+properties:
+  compatible:
+    items:
+      - enum:  

That's not an enum, but simple const without items.

Ok.

quoted

quoted

+          - arm,pl353-nand-r2p1
+
+  reg:
+    items:
+      - items:
+          - description: CS with regard to the parent ranges property
+          - description: Offset of the memory region requested by the device
+          - description: Length of the memory region requested by the device  

Doesn't it depend on parent's address/size cells?

Yes, but as the child nodes are not defined in the parent's binding
(ie. the SMC) I think it's interesting to have them defined here, no?

The trouble is if parent decides to have different address/size cells.
The schema will stop matching. I am actually not that sure if such case
is real since the pl353 NAND part will usually be connected to pl353
SMC. However the schema now hard-codes specific dependency against
parent schema/node.

Rob,
Maybe you have here some thoughts?

Best regards,
Krzysztof