[PATCH v2 1/3] dt-bindings: nvmem: add STM32MPX TAMP backup registers

[Patrice Chotard <patrice.chotard@foss.st.com>]

From: Simeon Marijon <simeon.marijon@foss.st.com>

Adds the binding documentation for TAMP backup registers.
The backup registers is a part of the TAMP device of STM32 MPU.

Signed-off-by: Simeon Marijon <simeon.marijon@foss.st.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
---
 .../bindings/nvmem/st,stm32-tamp-nvram.yaml        | 57 ++++++++++++++++++++++
 MAINTAINERS                                        |  7 +++
 2 files changed, 64 insertions(+)

diff --git a/Documentation/devicetree/bindings/nvmem/st,stm32-tamp-nvram.yaml b/Documentation/devicetree/bindings/nvmem/st,stm32-tamp-nvram.yaml
new file mode 100644
index 000000000000..4af3b88db566
--- /dev/null
+++ b/Documentation/devicetree/bindings/nvmem/st,stm32-tamp-nvram.yaml
@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/nvmem/st,stm32-tamp-nvram.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: STMicroelectronics STM32 backup registers as NVMEM
+
+description: |
+  This represents STM32 backup registers area presented as nvmem cells.
+  This contains various information (e.g. boot mode passed to bootloaders).
+
+maintainers:
+  - Simeon Marijon <simeon.marijon@foss.st.com>
+  - Patrice Chotard <patrice.chotard@foss.st.com>
+
+allOf:
+  - $ref: nvmem.yaml#
+
+properties:
+  compatible:
+    enum:
+      - st,stm32mp15-tamp-nvram
+      - st,stm32mp25-tamp-nvram
+
+  reg:
+    description:
+      TAMP Registers bank location and size.
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    nvram: nvram@5c00a100 {
+      reg = <0x5c00a100 0x80>;
+      compatible = "st,stm32mp15-tamp-nvram";
+
+      nvmem-layout {
+        compatible = "fixed-layout";
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        /* Data cells */
+        wakeup_sec: tamp-bkp@0 {
+            reg = <0x0 0x4>;
+        };
+        boot_mode: tamp-bkp@50 {
+            /*see boot mode selection feature*/
+            reg = <0x50 0x4>;
+        };
+      };
+    };
diff --git a/MAINTAINERS b/MAINTAINERS
index 3a19da74d00c..b634c037c229 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -26261,6 +26261,13 @@ F:	Documentation/arch/arm/stm32/stm32-dma-mdma-chaining.rst
 F:	Documentation/devicetree/bindings/dma/stm32/
 F:	drivers/dma/stm32/
 
+STM32 TAMP DRIVERS
+M:	Simeon Marijon <simeon.marijon@foss.st.com>
+M:	Patrice Chotard <patrice.chotard@foss.st.com>
+L:	linux-stm32@st-md-mailman.stormreply.com (moderated for non-subscribers)
+S:	Maintained
+F:	Documentation/devicetree/bindings/nvmem/st,stm32-tamp-nvram.yaml
+
 STM32 TIMER/LPTIMER DRIVERS
 M:	Fabrice Gasnier <fabrice.gasnier@foss.st.com>
 S:	Maintained

-- 
2.43.0