net: ot: rework NCP interface configuration

Rework NCP interface configuration and NCP sample. Remove
CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_DEV_NAME and
CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_ACM Kconfig
options in favor of chosen node zephyr,ot-uart usage.

Signed-off-by: Johann Fischer <johann.fischer@nordicsemi.no>

doc/reference/devicetree/api.rst

@@ -339,6 +339,8 @@ device.
        interprocess-communication (IPC)
    * - zephyr,itcm
      - Instruction Tightly Coupled Memory node on some Arm SoCs
+   * - zephyr,ot-uart
+     - Used by the OpenThread to specify UART device for Spinel protocol
    * - zephyr,shell-uart
      - Sets default :kconfig:`CONFIG_UART_SHELL_ON_DEV_NAME`
    * - zephyr,sram

doc/releases/release-notes-2.7.rst

@@ -47,6 +47,10 @@ Removed APIs in this release
 * Removed support for the Kconfig ``USB`` option. Option ``USB_DEVICE_STACK``
   is sufficient to enable USB device support.
 
+* Removed ``CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_ACM`` and
+  ``CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_DEV_NAME`` Kconfig options
+  in favor of chosen node ``zephyr,ot-uart``.
+
 ============================
 
 Stable API changes in this release

samples/net/openthread/coprocessor/README.rst

@@ -32,6 +32,15 @@ Build the OpenThread NCP sample application like this:
    :goals: build
    :compact:
 
+Build the OpenThread NCP sample application which uses CDC ACM UART device:
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/net/openthread/coprocessor
+   :board: nrf52840dk_nrf52840
+   :goals: build flash
+   :gen-args: -DDTC_OVERLAY_FILE=usb.overlay -DOVERLAY_CONFIG=overlay-usb-nrf-br.conf
+   :compact:
+
 Example building for the nrf52840dk_nrf52840 for RCP:
 
 .. zephyr-app-commands::

samples/net/openthread/coprocessor/app.overlay

@@ -0,0 +1,12 @@
+/*
+ * Copyright (c) 2021 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/ {
+	chosen {
+		zephyr,ot-uart = &uart0;
+		zephyr,console = &uart1;
+	};
+};

samples/net/openthread/coprocessor/overlay-tri-n4m-br.conf

@@ -1,16 +1,6 @@
 # TRI n4m BR
-# Use UART_0 for Shell/Console
-CONFIG_UART_SHELL_ON_DEV_NAME="UART_0"
-CONFIG_UART_CONSOLE_ON_DEV_NAME="UART_0"
 CONFIG_SHELL_PROMPT_UART="ncp-uart:~$ "
 
-# Use UART_1 for Co-Processor
-#CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_DEV_NAME="UART_1"
-
-# Use USB-CDC-ACM for NCP
-CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_ACM=y
-CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_DEV_NAME="CDC_ACM_0"
-
 CONFIG_STDOUT_CONSOLE=y
 CONFIG_GPIO=y
 CONFIG_USB_DEVICE_STACK=y

samples/net/openthread/coprocessor/overlay-usb-nrf-br.conf

@@ -1,13 +1,8 @@
 # Nordic NCP USB CDC-ACM
 
-# Use UART_0 for Shell/Console
-CONFIG_UART_SHELL_ON_DEV_NAME="UART_0"
-CONFIG_UART_CONSOLE_ON_DEV_NAME="UART_0"
 CONFIG_SHELL_PROMPT_UART="ncp-uart:~$ "
 
 # Use USB-CDC-ACM for Co-Processor
-CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_ACM=y
-CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_DEV_NAME="CDC_ACM_0"
 CONFIG_USB_DEVICE_STACK=y
 CONFIG_USB_DEVICE_PRODUCT="OpenThread CoProcessor NRF"
 CONFIG_USB_CDC_ACM=y

samples/net/openthread/coprocessor/prj.conf

@@ -33,6 +33,3 @@ CONFIG_OPENTHREAD_BORDER_AGENT=y
 CONFIG_OPENTHREAD_BORDER_ROUTER=y
 CONFIG_OPENTHREAD_UDP_FORWARD=y
 CONFIG_OPENTHREAD_ENABLE_SERVICE=y
-
-# Move console to other UART to not interfere with NCP
-CONFIG_UART_CONSOLE_ON_DEV_NAME="UART_1"

samples/net/openthread/coprocessor/sample.yaml

@@ -16,6 +16,7 @@ tests:
     platform_allow: nrf52840dk_nrf52840 nrf52833dk_nrf52833
     tags: ci_build
     extra_args: OVERLAY_CONFIG=overlay-usb-nrf-br.conf
+                DTC_OVERLAY_FILE="usb.overlay"
   samples.openthread.coprocessor.rcp:
     build_only: true
     platform_allow: nrf52840dk_nrf52840 nrf52833dk_nrf52833

samples/net/openthread/coprocessor/usb.overlay

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2021 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/ {
+	chosen {
+		zephyr,ot-uart = &cdc_acm_uart0;
+	};
+};
+
+&zephyr_udc0 {
+	cdc_acm_uart0: cdc_acm_uart0 {
+		compatible = "zephyr,cdc-acm-uart";
+		label = "CDC_ACM_0";
+	};
+};

subsys/logging/Kconfig.backends

@@ -187,7 +187,7 @@ endif # LOG_BACKEND_RTT
 
 config LOG_BACKEND_SPINEL
 	bool "Enable OpenThread dedicated Spinel protocol backend"
-	depends on (OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_DEV_NAME!=UART_CONSOLE_ON_DEV_NAME || !LOG_BACKEND_UART)
+	depends on !LOG_BACKEND_UART
 	depends on NET_L2_OPENTHREAD
 	help
 	  When enabled, backend will use OpenThread dedicated SPINEL protocol for logging.

subsys/net/l2/openthread/Kconfig

@@ -233,24 +233,12 @@ config OPENTHREAD_COPROCESSOR_RCP
 	bool "RCP - Radio Co-Processor"
 endchoice
 
-config OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_DEV_NAME
-	string "UART device to use for Co-Processor SPINEL"
-	default "UART_0"
-	help
-	  UART device to use for Co-Processor SPINEL.
-
 config OPENTHREAD_COPROCESSOR_UART_RING_BUFFER_SIZE
 	int "Set Co-Processor UART ring buffer size"
 	default 4096
 	help
 	  TX buffer size for the OpenThread Co-Processor UART.
 
-config OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_ACM
-	bool "Run SPINEL over USB-ACM"
-	depends on USB_CDC_ACM
-	help
-	  Is the SPINEL device a USB-CDC-ACM device.
-
 config OPENTHREAD_COPROCESSOR_VENDOR_HOOK_SOURCE
 	string "Path to vendor hook source file"
 	help

subsys/net/lib/openthread/platform/uart.c

@@ -19,9 +19,7 @@ LOG_MODULE_REGISTER(LOG_MODULE_NAME);
 #include <sys/ring_buffer.h>
 #include <sys/atomic.h>
 
-#ifdef CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_ACM
 #include <usb/usb_device.h>
-#endif
 
 #include <openthread/ncp.h>
 #include <openthread-system.h>
@@ -159,11 +157,10 @@ void platformUartProcess(otInstance *aInstance)
 
 otError otPlatUartEnable(void)
 {
-	ot_uart.dev = device_get_binding(
+	ot_uart.dev = DEVICE_DT_GET(DT_CHOSEN(zephyr_ot_uart));
-		CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_DEV_NAME);
 
-	if ((&ot_uart)->dev == NULL) {
+	if (!device_is_ready(ot_uart.dev)) {
-		LOG_ERR("UART device not found");
+		LOG_ERR("UART device not ready");
 		return OT_ERROR_FAILED;
 	}
 
@@ -171,8 +168,7 @@ otError otPlatUartEnable(void)
 					uart_callback,
 					(void *)&ot_uart);
 
-#ifdef CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_ACM
+	if (DT_NODE_HAS_COMPAT(DT_CHOSEN(zephyr_ot_uart), zephyr_cdc_acm_uart)) {
-	{
 		int ret;
 		uint32_t dtr = 0U;
 
@@ -201,7 +197,6 @@ otError otPlatUartEnable(void)
 		/* Data Set Ready - the NCP SoC is ready to communicate */
 		(void)uart_line_ctrl_set(ot_uart.dev, UART_LINE_CTRL_DSR, 1);
 	}
-#endif /* CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_ACM */
 
 	uart_irq_rx_enable(ot_uart.dev);
 
@@ -210,13 +205,13 @@ otError otPlatUartEnable(void)
 
 otError otPlatUartDisable(void)
 {
-#ifdef CONFIG_OPENTHREAD_COPROCESSOR_SPINEL_ON_UART_ACM
+	if (DT_NODE_HAS_COMPAT(DT_CHOSEN(zephyr_ot_uart), zephyr_cdc_acm_uart)) {
-	int ret = usb_disable();
+		int ret = usb_disable();
 
-	if (ret) {
+		if (ret) {
-		LOG_WRN("Failed to disable USB (%d)", ret);
+			LOG_WRN("Failed to disable USB (%d)", ret);
+		}
 	}
-#endif
 
 	uart_irq_tx_disable(ot_uart.dev);
 	uart_irq_rx_disable(ot_uart.dev);