Realtek SPI-NAND controller

Merge series from Chris Packham <[email protected]>:

This series adds support for the SPI-NAND flash controller on the RTL9300
family of SoCs.

There are 2 physical chip selects which are called SPI_MST_CS0 and SPI_MST_CS1
in the datasheet. Via some pin-strapping these can be assigned to either the
SPI-NOR controller or the SPI-NAND controller. Which means you can end up with
the following permutations

  SPI-Flash
  Boot Model SPI_MST_CS0 SPI_MST_CS1
  ---------- ----------- -----------
  NOR x1     NOR-CS0     X
  NOR x2     NOR-CS0     NOR-CS1
  NAND x1    NAND-CS0    X
  NAND x2    NAND-CS0    NAND-CS1
  NOR+NAND   NOR-CS0     NAND-CS0

Author: broonie

Documentation/devicetree/bindings/spi/realtek,rtl9301-snand.yaml

@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/realtek,rtl9301-snand.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SPI-NAND Flash Controller for Realtek RTL9300 SoCs
+
+maintainers:
+  - Chris Packham <[email protected]>
+
+description:
+  The Realtek RTL9300 SoCs have a built in SPI-NAND controller. It supports
+  typical SPI-NAND page cache operations in single, dual or quad IO mode.
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - enum:
+              - realtek,rtl9302b-snand
+              - realtek,rtl9302c-snand
+              - realtek,rtl9303-snand
+          - const: realtek,rtl9301-snand
+      - const: realtek,rtl9301-snand
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+
+allOf:
+  - $ref: /schemas/spi/spi-controller.yaml#
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    spi@1a400 {
+      compatible = "realtek,rtl9302c-snand", "realtek,rtl9301-snand";
+      reg = <0x1a400 0x44>;
+      interrupt-parent = <&intc>;
+      interrupts = <19>;
+      clocks = <&lx_clk>;
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      flash@0 {
+        compatible = "spi-nand";
+        reg = <0>;
+      };
+    };

MAINTAINERS

@@ -19538,6 +19538,12 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/net/dsa/realtek.yaml
 F:	drivers/net/dsa/realtek/*
 
+REALTEK SPI-NAND
+M:	Chris Packham <[email protected]>
+S:	Maintained
+F:	Documentation/devicetree/bindings/spi/realtek,rtl9301-snand.yaml
+F:	drivers/spi/spi-realtek-rtl-snand.c
+
 REALTEK WIRELESS DRIVER (rtlwifi family)
 M:	Ping-Ke Shih <[email protected]>
 L:	[email protected]

drivers/spi/Kconfig

@@ -843,6 +843,17 @@ config SPI_PXA2XX
 config SPI_PXA2XX_PCI
 	def_tristate SPI_PXA2XX && PCI && COMMON_CLK
 
+config SPI_REALTEK_SNAND
+	tristate "Realtek SPI-NAND Flash Controller"
+	depends on MACH_REALTEK_RTL || COMPILE_TEST
+	select REGMAP
+	help
+	  This enables support for the SPI-NAND Flash controller on
+	  Realtek SoCs.
+
+	  This driver does not support generic SPI. The implementation
+	  only supports the spi-mem interface.
+
 config SPI_ROCKCHIP
 	tristate "Rockchip SPI controller driver"
 	depends on ARCH_ROCKCHIP || COMPILE_TEST

drivers/spi/Makefile

@@ -119,6 +119,7 @@ obj-$(CONFIG_SPI_ROCKCHIP)		+= spi-rockchip.o
 obj-$(CONFIG_SPI_ROCKCHIP_SFC)		+= spi-rockchip-sfc.o
 obj-$(CONFIG_SPI_RB4XX)			+= spi-rb4xx.o
 obj-$(CONFIG_MACH_REALTEK_RTL)		+= spi-realtek-rtl.o
+obj-$(CONFIG_SPI_REALTEK_SNAND)		+= spi-realtek-rtl-snand.o
 obj-$(CONFIG_SPI_RPCIF)			+= spi-rpc-if.o
 obj-$(CONFIG_SPI_RSPI)			+= spi-rspi.o
 obj-$(CONFIG_SPI_RZV2M_CSI)		+= spi-rzv2m-csi.o