[PATCH v3 02/10] dt-bindings: iio: dac: adi-axi-adc: add ad7606 variant

[Angelo Dureghello <adureghello@xxxxxxxxxxxx>]

From: Guillaume Stols <gstols@xxxxxxxxxxxx>

A new compatible is added to reflect the specialized version of the HDL.
We use the parallel interface to write the ADC's registers, and
accessing this interface requires to use ADI_AXI_REG_CONFIG_RD,
ADI_AXI_REG_CONFIG_WR and ADI_AXI_REG_CONFIG_CTRL in a custom fashion.

Signed-off-by: Guillaume Stols <gstols@xxxxxxxxxxxx>
Co-developed-by: Angelo Dureghello <adureghello@xxxxxxxxxxxx>
Signed-off-by: Angelo Dureghello <adureghello@xxxxxxxxxxxx>
---
 .../devicetree/bindings/iio/adc/adi,axi-adc.yaml   | 70 +++++++++++++++++++++-
 1 file changed, 69 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/iio/adc/adi,axi-adc.yaml b/Documentation/devicetree/bindings/iio/adc/adi,axi-adc.yaml
index e1f450b80db2..4fa82dcf6fc9 100644
--- a/Documentation/devicetree/bindings/iio/adc/adi,axi-adc.yaml
+++ b/Documentation/devicetree/bindings/iio/adc/adi,axi-adc.yaml
@@ -17,13 +17,23 @@ description: |
   interface for the actual ADC, while this IP core will interface
   to the data-lines of the ADC and handle the streaming of data into
   memory via DMA.
+  In some cases, the AXI ADC interface is used to perform specialized
+  operation to a particular ADC, e.g access the physical bus through
+  specific registers to write ADC registers.
+  In this case, we use a different compatible which indicates the target
+  IP core's name.
+  The following IP is currently supported:
+    - AXI AD7606x: specialized version of the IP core for all the chips from
+      the ad7606 family.
 
   https://wiki.analog.com/resources/fpga/docs/axi_adc_ip
+  http://analogdevicesinc.github.io/hdl/library/axi_ad7606x/index.html
 
 properties:
   compatible:
     enum:
       - adi,axi-adc-10.0.a
+      - adi,axi-ad7606x
 
   reg:
     maxItems: 1
@@ -47,17 +57,48 @@ properties:
   '#io-backend-cells':
     const: 0
 
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+patternProperties:
+  "^adc@[0-9a-f]+$":
+    type: object
+    properties:
+      reg:
+        maxItems: 1
+    additionalProperties: true
+    required:
+      - compatible
+      - reg
+
 required:
   - compatible
   - dmas
   - reg
   - clocks
 
+allOf:
+  - if:
+      properties:
+        compatible:
+          not:
+            contains:
+              const: adi,axi-ad7606x
+    then:
+      properties:
+        '#address-cells': false
+        '#size-cells': false
+      patternProperties:
+        "^adc@[0-9a-f]+$": false
+
 additionalProperties: false
 
 examples:
   - |
-    axi-adc@44a00000 {
+    adc@44a00000 {
         compatible = "adi,axi-adc-10.0.a";
         reg = <0x44a00000 0x10000>;
         dmas = <&rx_dma 0>;
@@ -65,4 +106,31 @@ examples:
         clocks = <&axi_clk>;
         #io-backend-cells = <0>;
     };
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    parallel_bus_controller@44a00000 {
+        compatible = "adi,axi-ad7606x";
+        reg = <0x44a00000 0x10000>;
+        dmas = <&rx_dma 0>;
+        dma-names = "rx";
+        clocks = <&ext_clk>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        adc@0 {
+            compatible = "adi,ad7606b";
+            reg = <0>;
+            pwms = <&axi_pwm_gen 0 0>;
+            pwm-names = "convst1";
+            avcc-supply = <&adc_vref>;
+            vdrive-supply = <&vdd_supply>;
+            reset-gpios = <&gpio0 91 GPIO_ACTIVE_HIGH>;
+            standby-gpios = <&gpio0 90 GPIO_ACTIVE_LOW>;
+            adi,range-gpios = <&gpio0 89 GPIO_ACTIVE_HIGH>;
+            adi,oversampling-ratio-gpios = <&gpio0 88 GPIO_ACTIVE_HIGH
+                            &gpio0 87 GPIO_ACTIVE_HIGH
+                            &gpio0 86 GPIO_ACTIVE_HIGH>;
+            io-backends = <&parallel_bus_controller>;
+        };
+    };
 ...

-- 
2.47.0