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[3/4] dt-bindings: spi: add binding doc for spi-mtk-snfi

Message ID 20220403131154.1267887-4-gch981213@gmail.com
State Superseded
Headers show
Series spi: add support for Mediatek SPI-NAND controller | expand

Commit Message

Chuanhong Guo April 3, 2022, 1:11 p.m. UTC 
Add device-tree binding documentation for Mediatek SPI-NAND Flash
Interface.

Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
---
 .../bindings/spi/mediatek,spi-mtk-snfi.yaml   | 87 +++++++++++++++++++
 1 file changed, 87 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/spi/mediatek,spi-mtk-snfi.yaml

Comments

Krzysztof Kozlowski April 3, 2022, 3:49 p.m. UTC | #1 
On 03/04/2022 17:45, Chuanhong Guo wrote:
> Hi!
> 
> On Sun, Apr 3, 2022 at 11:37 PM Krzysztof Kozlowski
> <krzysztof.kozlowski@linaro.org> wrote:
>> [...]
>>> +  compatible:
>>> +    enum:
>>> +      - mediatek,mt7622-snand
>>> +      - mediatek,mt7629-snand
>>
>> One blank line, please.
> 
> I'll fix this in the next version.
> 
>>
>>> +  reg:
>>> +    items:
>>> +      - description: core registers
>>> +
>>> +  interrupts:
>>> +    items:
>>> +      - description: NFI interrupt
>>> +
>>> +  clocks:
>>> +    items:
>>> +      - description: clock used for the controller
>>> +      - description: clock used for the SPI bus
>>> +
>>> +  clock-names:
>>> +    items:
>>> +      - const: nfi_clk
>>> +      - const: pad_clk
>>> +
>>> +  ecc-engine:
>>
>> The nand-chip.yaml defines a nand-ecc-engine, so how about using that
>> one? I know mtk-nand.txt uses ecc-engine, but for new schema better to
>> use properties from existing YAML.
> 
> The ecc-engine code is shared between mtk_nand.c and this driver, and
> the property name is defined in the shared part. I left it as-is so that
> existing dt for mtk_nand doesn't break.

This can be easily fixed with:
	np = of_parse_phandle(of_node, "nand-ecc-engine", 0);
	if (!np) {
		/* Backwards compatible */
		np = of_parse_phandle(of_node, "ecc-engine", 0);
	}

I would like to avoid having one property in generic NAND schema and
keep adding something slightly different everywhere else.

Best regards,
Krzysztof
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/spi/mediatek,spi-mtk-snfi.yaml b/Documentation/devicetree/bindings/spi/mediatek,spi-mtk-snfi.yaml
new file mode 100644
index 000000000000..166c6b50b9d1
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/mediatek,spi-mtk-snfi.yaml
@@ -0,0 +1,87 @@ 
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/mediatek,spi-mtk-snfi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SPI-NAND flash controller for MediaTek ARM SoCs
+
+maintainers:
+  - Chuanhong Guo <gch981213@gmail.com>
+
+description: |
+  The Mediatek SPI-NAND flash controller is an extended version of
+  the Mediatek NAND flash controller. It can perform standard SPI
+  instructions with one continuous write and one read for up-to 0xa0
+  bytes. It also supports typical SPI-NAND page cache operations
+  in single, dual or quad IO mode with piplined ECC encoding/decoding
+  using the accompanying ECC engine. There should be only one spi
+  slave device following generic spi bindings.
+
+allOf:
+  - $ref: /schemas/spi/spi-controller.yaml#
+
+properties:
+  compatible:
+    enum:
+      - mediatek,mt7622-snand
+      - mediatek,mt7629-snand
+  reg:
+    items:
+      - description: core registers
+
+  interrupts:
+    items:
+      - description: NFI interrupt
+
+  clocks:
+    items:
+      - description: clock used for the controller
+      - description: clock used for the SPI bus
+
+  clock-names:
+    items:
+      - const: nfi_clk
+      - const: pad_clk
+
+  ecc-engine:
+    description: device-tree node of the accompanying ECC engine.
+    $ref: /schemas/types.yaml#/definitions/phandle
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+  - ecc-engine
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/clock/mt7622-clk.h>
+    soc {
+      #address-cells = <2>;
+      #size-cells = <2>;
+      snfi: spi@1100d000 {
+        compatible = "mediatek,mt7622-snand";
+        reg = <0 0x1100d000 0 0x1000>;
+        interrupts = <GIC_SPI 96 IRQ_TYPE_LEVEL_LOW>;
+        clocks = <&pericfg CLK_PERI_NFI_PD>, <&pericfg CLK_PERI_SNFI_PD>;
+        clock-names = "nfi_clk", "pad_clk";
+        ecc-engine = <&bch>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        flash@0 {
+          compatible = "spi-nand";
+          reg = <0>;
+          spi-tx-bus-width = <4>;
+          spi-rx-bus-width = <4>;
+          nand-ecc-engine = <&snfi>;
+        };
+      };
+    };