boards: st: nucleo_u385rg_q: change arduino_spi to spi1

According to user manual(UM3062, table 16), arduino_spi is connected
to spi1 instead of spi3.

Enable spi1 node and affect the SPI_NSS pin with I/O function
to do the chip select.

Remove i2c3 to avoid conflict with PA7 pin.

NB: The SPI_NSS pin is not listed as an alternate function
for SPI1 in the user manual (UM3062, Table 17).

Signed-off-by: Ulrich KAMDEM <kamdemulricharmel@gmail.com>

Author: ulrich-a11-y

boards/st/nucleo_u385rg_q/arduino_r3_connector.dtsi

@@ -39,6 +39,6 @@
 
 arduino_i2c: &i2c1 {};
 
-arduino_spi: &spi3 {};
+arduino_spi: &spi1 {};
 
 arduino_serial: &lpuart1 {};

boards/st/nucleo_u385rg_q/nucleo_u385rg_q.dts

@@ -145,9 +145,9 @@
 };
 
 &dac1 {
-	status = "okay";
 	pinctrl-0 = <&dac1_out1_pa4>;
 	pinctrl-names = "default";
+	status = "okay";
 };
 
 &fdcan1 {
@@ -168,18 +168,25 @@
 	status = "okay";
 };
 
-&i2c3 {
-	pinctrl-0 = <&i2c3_scl_pa7 &i2c3_sda_pc1>;
-	pinctrl-names = "default";
-	status = "okay";
-};
-
 &rng {
 	clocks = <&rcc STM32_CLOCK(AHB2, 18)>,
 		 <&rcc STM32_SRC_MSIK RNG_SEL(1)>;
 	status = "okay";
 };
 
+&spi1 {
+	pinctrl-0 = <&spi1_sck_pa5 &spi1_miso_pa6 
+		     &spi1_mosi_pa7>;
+	pinctrl-names = "default";
+
+	/* Arduino D10 (SPI_NSS) is wired to PC9 which
+	 * doesn't support hardware NSS; the software
+	 * cs-gpios must be used instead.
+	 */
+	cs-gpios = <&gpioc 9 GPIO_ACTIVE_LOW>;
+	status = "okay";
+};
+
 &spi3 {
 	pinctrl-0 = <&spi3_nss_pa15 &spi3_sck_pb3
 		     &spi3_miso_pb4 &spi3_mosi_pb5>;