boards: arm: sam4s_xplained: Enable DAC support

Enable DAC entry in device tree and pinctrl (PB13/PB14).
Update doc/yaml files to include ADC info.
Update the sample for sam4s_xplained.

Signed-off-by: Ibe Van de Veire <ibe.vandeveire@basalte.be>

Author: IVandeVeire

boards/atmel/sam/sam4s_xplained/doc/index.rst

@@ -37,6 +37,8 @@ features:
 +-----------+------------+-------------------------------------+
 | COUNTER   | on-chip    | counter                             |
 +-----------+------------+-------------------------------------+
+| DAC       | on-chip    | dac                                 |
++-----------+------------+-------------------------------------+
 | GPIO      | on-chip    | gpio                                |
 +-----------+------------+-------------------------------------+
 | HWINFO    | on-chip    | Unique device serial number         |

boards/atmel/sam/sam4s_xplained/sam4s_xplained-pinctrl.dtsi

@@ -59,6 +59,13 @@
 		};
 	};
 
+	dacc_default: dacc_default {
+		group1 {
+			pinmux = <PB13D_DACC_DAC0>,
+				 <PB14D_DACC_DAC1>;
+		};
+	};
+
 	smc_default: smc_default {
 		group1 {
 			pinmux = <PC18A_EBI_A0>,

boards/atmel/sam/sam4s_xplained/sam4s_xplained.dts

@@ -190,6 +190,13 @@
 	tracking-time = <2>;
 };
 
+&dacc {
+	status = "okay";
+
+	pinctrl-0 = <&dacc_default>;
+	pinctrl-names = "default";
+};
+
 &wdt {
 	status = "okay";
 };

boards/atmel/sam/sam4s_xplained/sam4s_xplained.yaml

@@ -10,6 +10,7 @@ ram: 128
 supported:
   - adc
   - counter
+  - dac
   - gpio
   - hwinfo
   - memc

samples/drivers/dac/boards/sam4s_xplained.overlay

@@ -0,0 +1,7 @@
+/ {
+	zephyr,user {
+		dac = <&dacc>;
+		dac-channel-id = <0>;
+		dac-resolution = <12>;
+	};
+};