Hi, Rob,

On 23.07.2024 05:17, Rob Herring wrote:

On Tue, Jul 16, 2024 at 01:30:15PM +0300, Claudiu wrote:

quoted

From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>

The VBATTB IP of the Renesas RZ/G3S SoC controls the clock for RTC,
the tamper detector and a small general usage memory of 128B. Add
documentation for it.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
---

Changes in v2:
- changed file name and compatible
- updated title, description sections
- added clock controller part documentation and drop dedicated file
  for it included in v1
- used items to describe interrupts, interrupt-names, clocks, clock-names,
  resets
- dropped node labels and status
- updated clock-names for clock controller to cope with the new
  logic on detecting the necessity to setup bypass

 .../mfd/renesas,r9a08g045-vbattb.yaml         | 136 ++++++++++++++++++
 1 file changed, 136 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mfd/renesas,r9a08g045-vbattb.yaml

diff --git a/Documentation/devicetree/bindings/mfd/renesas,r9a08g045-vbattb.yaml b/Documentation/devicetree/bindings/mfd/renesas,r9a08g045-vbattb.yaml
new file mode 100644
index 000000000000..30e4da65e2f6
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/renesas,r9a08g045-vbattb.yaml

@@ -0,0 +1,136 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/renesas,r9a08g045-vbattb.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Renesas Battery Backup Function (VBATTB)
+
+description:
+  Renesas VBATTB is an always on powered module (backed by battery) which
+  controls the RTC clock (VBATTCLK), tamper detection logic and a small
+  general usage memory (128B).
+
+maintainers:
+  - Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
+
+properties:
+  compatible:
+    const: renesas,r9a08g045-vbattb
+
+  reg:
+    maxItems: 1
+
+  ranges: true
+
+  interrupts:
+    items:
+      - description: tamper detector interrupt
+
+  interrupt-names:
+    items:
+      - const: tampdi

Don't really need -names with only 1 entry.

quoted

+
+  clocks:
+    items:
+      - description: VBATTB module clock
+
+  clock-names:
+    items:
+      - const: bclk
+
+  power-domains:
+    maxItems: 1
+
+  resets:
+    items:
+      - description: VBATTB module reset
+
+  '#address-cells':
+    const: 2
+
+  '#size-cells':
+    const: 2
+
+patternProperties:
+  "^clock-controller@1c+$":
+    type: object
+    description: VBATTCLK clock
+
+    properties:
+      compatible:
+        const: renesas,r9a08g045-vbattb-clk
+
+      reg:
+        maxItems: 1
+
+      clocks:
+        items:
+          - description: input clock for VBATTCLK
+
+      clock-names:
+        description: |
+          Use xin if connected to an external crystal oscillator.
+          Use clkin if connected to an external hardware device generating the
+          clock.
+        enum:
+          - xin
+          - clkin
+
+      '#clock-cells':
+        const: 0
+
+      renesas,vbattb-load-nanofarads:
+        description: load capacitance of the on board xtal
+        $ref: /schemas/types.yaml#/definitions/uint32
+        enum: [ 4000, 7000, 9000, 12500 ]
+
+    required:
+      - compatible
+      - reg
+      - clocks
+      - clock-names
+      - '#clock-cells'
+      - renesas,vbattb-load-nanofarads
+
+    additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - interrupt-names
+  - clocks
+  - clock-names
+  - power-domains
+  - resets
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/r9a08g045-cpg.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+    vbattb@1005c000 {
+        compatible = "renesas,r9a08g045-vbattb";
+        reg = <0x1005c000 0x1000>;
+        ranges = <0 0 0x1005c000 0 0x1000>;
+        interrupts = <GIC_SPI 43 IRQ_TYPE_LEVEL_HIGH>;
+        interrupt-names = "tampdi";
+        clocks = <&cpg CPG_MOD R9A08G045_VBAT_BCLK>;
+        clock-names = "bclk";
+        power-domains = <&cpg>;
+        resets = <&cpg R9A08G045_VBAT_BRESETN>;
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        clock-controller@1c {
+            compatible = "renesas,r9a08g045-vbattb-clk";
+            reg = <0 0x1c 0 0x10>;
+            clocks = <&vbattb_xtal>;
+            clock-names = "xin";
+            #clock-cells = <0>;
+            renesas,vbattb-load-nanofarads = <12500>;
+        };

Is this really a separate device?

It's not.

Doesn't really look like it. This can 
all be moved to the parent node.

I'll move it to the parent node.

Thank you for your review,
Claudiu Beznea

Rob