samples: usb: move the legacy code out of the CDC ACM sample

Move the legacy code of the CDC ACM sample to a separate sample in the
legacy directory.

Signed-off-by: Johann Fischer <[email protected]>

Author: jfischer-no

samples/subsys/usb/cdc_acm/README.rst

@@ -1,8 +1,8 @@
 .. zephyr:code-sample:: usb-cdc-acm
-   :name: USB CDC-ACM
-   :relevant-api: usbd_api _usb_device_core_api uart_interface
+   :name: USB CDC ACM UART sample
+   :relevant-api: usbd_api uart_interface
 
-   Use USB CDC-ACM driver to implement a serial port echo.
+   Use USB CDC ACM UART driver to implement a serial port echo.
 
 Overview
 ********

samples/subsys/usb/cdc_acm/prj.conf

@@ -1,11 +1,14 @@
+CONFIG_USB_DEVICE_STACK_NEXT=y
+
 CONFIG_STDOUT_CONSOLE=y
-CONFIG_USB_DEVICE_STACK=y
-CONFIG_USB_DEVICE_PRODUCT="Zephyr CDC ACM sample"
-CONFIG_USB_DEVICE_PID=0x0001
-CONFIG_LOG=y
-CONFIG_USB_DRIVER_LOG_LEVEL_ERR=y
-CONFIG_USB_DEVICE_LOG_LEVEL_ERR=y
 CONFIG_SERIAL=y
-CONFIG_UART_INTERRUPT_DRIVEN=y
 CONFIG_UART_LINE_CTRL=y
-CONFIG_USB_DEVICE_INITIALIZE_AT_BOOT=n
+CONFIG_USBD_CDC_ACM_CLASS=y
+
+CONFIG_LOG=y
+CONFIG_USBD_LOG_LEVEL_ERR=y
+CONFIG_UDC_DRIVER_LOG_LEVEL_ERR=y
+CONFIG_USBD_CDC_ACM_LOG_LEVEL_ERR=y
+
+CONFIG_SAMPLE_USBD_PID=0x0001
+CONFIG_SAMPLE_USBD_PRODUCT="USBD CDC ACM sample"

samples/subsys/usb/cdc_acm/sample.yaml

@@ -1,19 +1,9 @@
 sample:
   name: CDC ACM USB
 tests:
-  sample.usb.cdc-acm:
-    depends_on: usb_device
-    tags: usb
-    arch_exclude: posix
-    harness: console
-    harness_config:
-      type: one_line
-      regex:
-        - "Wait for DTR"
   sample.usb_device_next.cdc-acm:
     depends_on: usbd
     tags: usb
-    extra_args: CONF_FILE="usbd_next_prj.conf"
     integration_platforms:
       - nrf52840dk/nrf52840
       - nrf54h20dk/nrf54h20/cpuapp
@@ -34,7 +24,6 @@ tests:
     depends_on: usbd
     tags: usb
     extra_args:
-      - CONF_FILE="usbd_next_prj.conf"
       - DCONFIG_USBD_CDC_ACM_WORKQUEUE=y
     integration_platforms:
       - frdm_k64f
@@ -43,10 +32,3 @@ tests:
       type: one_line
       regex:
         - "Wait for DTR"
-  sample.usb.cdc-acm.buildonly:
-    depends_on: usb_device
-    tags: usb
-    arch_allow: posix
-    build_only: true
-    integration_platforms:
-      - native_sim

samples/subsys/usb/cdc_acm/src/main.c

@@ -4,14 +4,6 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-/**
- * @file
- * @brief Sample echo app for CDC ACM class
- *
- * Sample app for USB CDC ACM class driver. The received data is echoed back
- * to the serial port.
- */
-
 #include <sample_usbd.h>
 
 #include <stdio.h>
@@ -21,7 +13,6 @@
 #include <zephyr/kernel.h>
 #include <zephyr/sys/ring_buffer.h>
 
-#include <zephyr/usb/usb_device.h>
 #include <zephyr/usb/usbd.h>
 #include <zephyr/logging/log.h>
 LOG_MODULE_REGISTER(cdc_acm_echo, LOG_LEVEL_INF);
@@ -48,7 +39,6 @@ static inline void print_baudrate(const struct device *dev)
 	}
 }
 
-#if defined(CONFIG_USB_DEVICE_STACK_NEXT)
 static struct usbd_context *sample_usbd;
 K_SEM_DEFINE(dtr_sem, 0, 1);
 
@@ -106,7 +96,6 @@ static int enable_usb_device_next(void)
 
 	return 0;
 }
-#endif /* defined(CONFIG_USB_DEVICE_STACK_NEXT) */
 
 static void interrupt_handler(const struct device *dev, void *user_data)
 {
@@ -178,37 +167,16 @@ int main(void)
 		return 0;
 	}
 
-#if defined(CONFIG_USB_DEVICE_STACK_NEXT)
-		ret = enable_usb_device_next();
-#else
-		ret = usb_enable(NULL);
-#endif
-
+	ret = enable_usb_device_next();
 	if (ret != 0) {
-		LOG_ERR("Failed to enable USB");
+		LOG_ERR("Failed to enable USB device support");
 		return 0;
 	}
 
 	ring_buf_init(&ringbuf, sizeof(ring_buffer), ring_buffer);
 
 	LOG_INF("Wait for DTR");
-
-#if defined(CONFIG_USB_DEVICE_STACK_NEXT)
 	k_sem_take(&dtr_sem, K_FOREVER);
-#else
-	while (true) {
-		uint32_t dtr = 0U;
-
-		uart_line_ctrl_get(uart_dev, UART_LINE_CTRL_DTR, &dtr);
-		if (dtr) {
-			break;
-		} else {
-			/* Give CPU resources to low priority threads. */
-			k_sleep(K_MSEC(100));
-		}
-	}
-#endif
-
 	LOG_INF("DTR set");
 
 	/* They are optional, we use them to test the interrupt endpoint */
@@ -225,11 +193,7 @@ int main(void)
 	/* Wait 100ms for the host to do all settings */
 	k_msleep(100);
 
-#ifndef CONFIG_USB_DEVICE_STACK_NEXT
-	print_baudrate(uart_dev);
-#endif
 	uart_irq_callback_set(uart_dev, interrupt_handler);
-
 	/* Enable rx interrupts */
 	uart_irq_rx_enable(uart_dev);
 

samples/subsys/usb/cdc_acm/usbd_next_prj.conf

@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(cdc_acm)
+
+include(${ZEPHYR_BASE}/samples/subsys/usb/common/common.cmake)
+FILE(GLOB app_sources src/*.c)
+target_sources(app PRIVATE ${app_sources})

samples/subsys/usb/legacy/cdc_acm/CMakeLists.txt

@@ -0,0 +1,102 @@
+.. zephyr:code-sample:: legacy-usb-cdc-acm
+   :name: Legacy USB CDC ACM UART sample
+   :relevant-api: _usb_device_core_api uart_interface
+
+   Use USB CDC ACM UART driver to implement a serial port echo.
+
+Overview
+********
+
+This sample app demonstrates use of a USB Communication Device Class (CDC)
+Abstract Control Model (ACM) driver provided by the Zephyr project.
+Received data from the serial port is echoed back to the same port
+provided by this driver.
+
+.. note::
+   This samples demonstrate deprecated :ref:`usb_device_stack`.
+
+This sample can be found under :zephyr_file:`samples/subsys/usb/legacy/cdc_acm` in the
+Zephyr project tree.
+
+Requirements
+************
+
+This project requires an USB device driver, which is available for multiple
+boards supported in Zephyr.
+
+Building and Running
+********************
+
+Reel Board
+===========
+
+To see the console output of the app, open a serial port emulator and
+attach it to the USB to TTL Serial cable. Build and flash the project:
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/subsys/usb/legacy/cdc_acm
+   :board: reel_board
+   :goals: flash
+   :compact:
+
+Running
+=======
+
+Plug the board into a host device, for example, a PC running Linux.
+The board will be detected as shown by the Linux dmesg command:
+
+.. code-block:: console
+
+   usb 9-1: new full-speed USB device number 112 using uhci_hcd
+   usb 9-1: New USB device found, idVendor=8086, idProduct=f8a1
+   usb 9-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
+   usb 9-1: Product: CDC-ACM
+   usb 9-1: Manufacturer: Intel
+   usb 9-1: SerialNumber: 00.01
+   cdc_acm 9-1:1.0: ttyACM1: USB ACM device
+
+The app prints on serial output (UART1), used for the console:
+
+.. code-block:: console
+
+   Wait for DTR
+
+Open a serial port emulator, for example minicom
+and attach it to detected CDC ACM device:
+
+.. code-block:: console
+
+   minicom --device /dev/ttyACM1
+
+The app should respond on serial output with:
+
+.. code-block:: console
+
+   DTR set, start test
+   Baudrate detected: 115200
+
+And on ttyACM device, provided by zephyr USB device stack:
+
+.. code-block:: console
+
+   Send characters to the UART device
+   Characters read:
+
+The characters entered in serial port emulator will be echoed back.
+
+Troubleshooting
+===============
+
+If the ModemManager runs on your operating system, it will try
+to access the CDC ACM device and maybe you can see several characters
+including "AT" on the terminal attached to the CDC ACM device.
+You can add or extend the udev rule for your board to inform
+ModemManager to skip the CDC ACM device.
+For this example, it would look like this:
+
+.. code-block:: none
+
+   ATTRS{idVendor}=="8086" ATTRS{idProduct}=="f8a1", ENV{ID_MM_DEVICE_IGNORE}="1"
+
+You can use
+``/lib/udev/rules.d/77-mm-usb-device-blacklist.rules`` as reference.

samples/subsys/usb/legacy/cdc_acm/README.rst

@@ -0,0 +1,11 @@
+/*
+ * Copyright (c) 2021 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+&zephyr_udc0 {
+	cdc_acm_uart0 {
+		compatible = "zephyr,cdc-acm-uart";
+	};
+};

samples/subsys/usb/legacy/cdc_acm/app.overlay

@@ -0,0 +1,11 @@
+CONFIG_STDOUT_CONSOLE=y
+CONFIG_USB_DEVICE_STACK=y
+CONFIG_USB_DEVICE_PRODUCT="Zephyr CDC ACM sample"
+CONFIG_USB_DEVICE_PID=0x0001
+CONFIG_LOG=y
+CONFIG_USB_DRIVER_LOG_LEVEL_ERR=y
+CONFIG_USB_DEVICE_LOG_LEVEL_ERR=y
+CONFIG_SERIAL=y
+CONFIG_UART_INTERRUPT_DRIVEN=y
+CONFIG_UART_LINE_CTRL=y
+CONFIG_USB_DEVICE_INITIALIZE_AT_BOOT=n

samples/subsys/usb/legacy/cdc_acm/prj.conf

@@ -0,0 +1,7 @@
+sample:
+  name: CDC ACM USB
+tests:
+  sample.usb.legacy.cdc-acm:
+    depends_on: usb_device
+    tags: usb
+    build_only: true