On Wed, 25 Aug 2021 17:24:40 +0200
Miquel Raynal [off-list ref] wrote:

There is a very light description of this MFD in a text file dedicated
to a touchscreen controller (which is one of the two children of the
MFD). Here is now a complete yaml description.

Make sure to call out places where you are filling in gaps in the
txt file description.  Looks like we forgot to keep that up to date as the driver
evolved. oops.

text documents the more specific ti,am654-tscadc as well.
Something like

   properties:
     compatible:
       oneof:
         - const: ti,am3359-tscadc
         - items:
             - const: ti,am654-tscadc
             - const: ti,am3359-tscadc

Note this superceeds my comment on later patches about changing to enum when
introducing the new compatible. Ah well.

example for this would be something like
Documentation/devicetree/bindings/iio/adc/amlogic,meson-saradc.yam;

+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    const: fck
+
+  dmas:
+    items:
+      - description: DMA controller phandle and request line for FIFO0
+      - description: DMA controller phandle and request line for FIFO1
+
+  dma-names:
+    items:
+      - const: fifo0
+      - const: fifo1
+
+patternProperties:
+  "^adc$":
+    description: ADC
+
+  "^tsc$":
+    description: Touchscreen controller
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+  - dmas
+  - dma-names
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+    tscadc: tscadc@0 {
+        compatible = "ti,am3359-tscadc";
+        reg = <0x0 0x1000>;
+        interrupts = <GIC_SPI 16 IRQ_TYPE_LEVEL_HIGH>;
+        clocks = <&adc_tsc_fck>;
+        clock-names = "fck";
+        dmas = <&edma 53 0>, <&edma 57 0>;
+        dma-names = "fifo0", "fifo1";
+        status = "disabled";
+
+        tsc {
+        };
+
+        adc {
+        };
+    };