samples: stm32: mco: Add disco board which has 2 MCO instances

Add stm32f746g_disco board to MCO sample.
This board has 2 MCO instances so useful to show multiple instances
as well as checking the implementation.

Signed-off-by: Joakim Andersson <[email protected]>

Author: joerchan

samples/boards/st/mco/boards/stm32f746g_disco.overlay

@@ -0,0 +1,44 @@
+/* The clock that is output must be enabled. */
+&clk_lse {
+	status = "okay";
+};
+
+&clk_hse {
+	status = "okay";
+};
+
+/* See reference manual (RM0385):
+ *   0b01: LSE oscillator selected
+ */
+#define MCO1_SEL_LSE 1
+
+/* See reference manual (RM0385):
+ *   0b100: division by 2
+ */
+#define MCO1_PRE_DIV_2 4
+
+&mco1 {
+	status = "okay";
+	clocks = <&rcc STM32_SRC_LSE MCO1_SEL(MCO1_SEL_LSE)>;
+	prescaler = <MCO1_PRE(MCO1_PRE_DIV_2)>;
+	pinctrl-0 = <&rcc_mco_1_pa8>; /* D10 (CN7) */
+	pinctrl-names = "default";
+};
+
+/* See reference manual (RM0385):
+ *   0b10: HSE oscillator clock selected
+ */
+#define MCO2_SEL_HSE 2
+
+/* See reference manual (RM0385):
+ *   0b111: division by 5
+ */
+#define MCO2_PRE_DIV_5 7
+
+&mco2 {
+	status = "okay";
+	clocks = <&rcc STM32_SRC_HSE MCO2_SEL(MCO2_SEL_HSE)>;
+	prescaler = <MCO2_PRE(MCO2_PRE_DIV_5)>;
+	pinctrl-0 = <&rcc_mco_2_pc9>; /* uSD_D1 (CN3 pin 8) */
+	pinctrl-names = "default";
+};

samples/boards/st/mco/sample.yaml

@@ -2,5 +2,5 @@ sample:
   name: STM32 microcontroller clock output (MCO) example
 tests:
   sample.board.stm32.mco:
-    platform_allow: nucleo_u5a5zj_q
+    platform_allow: nucleo_u5a5zj_q stm32f746g_disco
     tags: board

samples/boards/st/mco/src/main.c

@@ -25,6 +25,16 @@ int main(void)
 		return -1;
 	}
 
+#if DT_NODE_HAS_STATUS(DT_NODELABEL(mco2), okay)
+	dev = DEVICE_DT_GET(DT_NODELABEL(mco2));
+	if (device_is_ready(dev)) {
+		printk("MCO2 device successfully configured\n");
+	} else {
+		printk("MCO2 device not ready\n");
+		return -1;
+	}
+#endif
+
 	printk("\nDisplayed the status of all MCO devices - end of example.\n");
 	return 0;
 }