Document the QPIC-SPI-NAND flash controller present in the IPQ SoCs.
It can work both in serial and parallel mode and supports typical
SPI-NAND page cache operations.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Md Sadre Alam <quic_mdalam@quicinc.com>
---

Change in [v13]

* No change

Change in [v12]

* Added Reviewed-by tag

Change in [v11]

* Dropped Reviewed-by tag
* Added Soc based compitable "qcom,ipq9574-snand"
 
Change in [v10]

* No change

Change in [v9]

* No change

Change in [v8]

* No change

Change in [v7]

* No change

Change in [v6]

* No change

Change in [v5]

* No change

Change in [v4]

* Fix spelling mistake in HW description

* Added commit message

* Removed '|' from description

* Removed minItems in clock

* Added blank line

* Removed co-developed by

Change in [v3]

* Updated commit message, removed "dt-bindings" from commit
  message

* Updated compatible name as file name

* Added hardware description

* Documented clock-name

* Moved dma-names property to top

* Droped unused label "qpic_nand"

* Fixed indentation in example dt node

Change in [v2]

* Added initial support for dt-bindings

Change in [v1]

* This patch was not included in [v1]

 .../bindings/spi/qcom,spi-qpic-snand.yaml     | 83 +++++++++++++++++++
 1 file changed, 83 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/spi/qcom,spi-qpic-snand.yaml

diff --git a/Documentation/devicetree/bindings/spi/qcom,spi-qpic-snand.yaml b/Documentation/devicetree/bindings/spi/qcom,spi-qpic-snand.yaml
new file mode 100644
index 000000000000..aa3f93319203
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/qcom,spi-qpic-snand.yaml
@@ -0,0 +1,83 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/qcom,spi-qpic-snand.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm QPIC NAND controller
+
+maintainers:
+  - Md sadre Alam <quic_mdalam@quicinc.com>
+
+description:
+  The QCOM QPIC-SPI-NAND flash controller is an extended version of
+  the QCOM QPIC NAND flash controller. It can work both in serial
+  and parallel mode. It supports typical SPI-NAND page cache
+  operations in single, dual or quad IO mode with pipelined ECC
+  encoding/decoding using the QPIC ECC HW engine.
+
+allOf:
+  - $ref: /schemas/spi/spi-controller.yaml#
+
+properties:
+  compatible:
+    enum:
+      - qcom,ipq9574-snand
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 3
+
+  clock-names:
+    items:
+      - const: core
+      - const: aon
+      - const: iom
+
+  dmas:
+    items:
+      - description: tx DMA channel
+      - description: rx DMA channel
+      - description: cmd DMA channel
+
+  dma-names:
+    items:
+      - const: tx
+      - const: rx
+      - const: cmd
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/qcom,ipq9574-gcc.h>
+    spi@79b0000 {
+        compatible = "qcom,ipq9574-snand";
+        reg = <0x1ac00000 0x800>;
+
+        clocks = <&gcc GCC_QPIC_CLK>,
+                 <&gcc GCC_QPIC_AHB_CLK>,
+                 <&gcc GCC_QPIC_IO_MACRO_CLK>;
+        clock-names = "core", "aon", "iom";
+
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        flash@0 {
+            compatible = "spi-nand";
+            reg = <0>;
+            #address-cells = <1>;
+            #size-cells = <1>;
+            nand-ecc-engine = <&qpic_nand>;
+            nand-ecc-strength = <4>;
+            nand-ecc-step-size = <512>;
+        };
+    };
-- 
2.34.1