usb: device_next: rework CDC ACM serial for flash usage

Allow optimization if high speed is not supported. Unify strings for
error logging. Allow the application to enable/disable the USB device.

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

Author: jfischer-no

subsys/usb/device_next/app/Kconfig.cdc_acm_serial

@@ -16,6 +16,13 @@ menuconfig CDC_ACM_SERIAL_INITIALIZE_AT_BOOT
 
 if CDC_ACM_SERIAL_INITIALIZE_AT_BOOT
 
+config CDC_ACM_SERIAL_ENABLE_AT_BOOT
+	bool "USB device will be enabled at boot"
+	default y
+	help
+	  When disabled, the application is responsible for enabling/disabling
+	  the USB device.
+
 config CDC_ACM_SERIAL_MANUFACTURER_STRING
 	string "USB device manufacturer string descriptor"
 	default "Zephyr Project"

subsys/usb/device_next/app/cdc_acm_serial.c

@@ -12,7 +12,7 @@
 #include <zephyr/usb/usbd.h>
 
 #include <zephyr/logging/log.h>
-LOG_MODULE_REGISTER(cdc_acm_serial, LOG_LEVEL_DBG);
+LOG_MODULE_REGISTER(cdc_acm_serial, CONFIG_USBD_LOG_LEVEL);
 
 /*
  * This is intended for use with cdc-acm-snippet or as a default serial backend
@@ -79,31 +79,32 @@ static int cdc_acm_serial_init_device(void)
 
 	err = usbd_add_descriptor(&cdc_acm_serial, &cdc_acm_serial_lang);
 	if (err) {
-		LOG_ERR("Failed to initialize language descriptor (%d)", err);
+		LOG_ERR("Failed to initialize %s (%d)", "language descriptor", err);
 		return err;
 	}
 
 	err = usbd_add_descriptor(&cdc_acm_serial, &cdc_acm_serial_mfr);
 	if (err) {
-		LOG_ERR("Failed to initialize manufacturer descriptor (%d)", err);
+		LOG_ERR("Failed to initialize %s (%d)", "manufacturer descriptor", err);
 		return err;
 	}
 
 	err = usbd_add_descriptor(&cdc_acm_serial, &cdc_acm_serial_product);
 	if (err) {
-		LOG_ERR("Failed to initialize product descriptor (%d)", err);
+		LOG_ERR("Failed to initialize %s (%d)", "product descriptor", err);
 		return err;
 	}
 
 	IF_ENABLED(CONFIG_HWINFO, (
 		err = usbd_add_descriptor(&cdc_acm_serial, &cdc_acm_serial_sn);
 	))
 	if (err) {
-		LOG_ERR("Failed to initialize SN descriptor (%d)", err);
+		LOG_ERR("Failed to initialize %s (%d)", "SN descriptor", err);
 		return err;
 	}
 
-	if (usbd_caps_speed(&cdc_acm_serial) == USBD_SPEED_HS) {
+	if (USBD_SUPPORTS_HIGH_SPEED &&
+	    usbd_caps_speed(&cdc_acm_serial) == USBD_SPEED_HS) {
 		err = register_cdc_acm_0(&cdc_acm_serial, USBD_SPEED_HS);
 		if (err) {
 			return err;
@@ -117,14 +118,16 @@ static int cdc_acm_serial_init_device(void)
 
 	err = usbd_init(&cdc_acm_serial);
 	if (err) {
-		LOG_ERR("Failed to initialize device support");
+		LOG_ERR("Failed to initialize %s (%d)", "device support", err);
 		return err;
 	}
 
-	err = usbd_enable(&cdc_acm_serial);
-	if (err) {
-		LOG_ERR("Failed to enable device support");
-		return err;
+	if (IS_ENABLED(CONFIG_CDC_ACM_SERIAL_ENABLE_AT_BOOT)) {
+		err = usbd_enable(&cdc_acm_serial);
+		if (err) {
+			LOG_ERR("Failed to enable %s (%d)", "device support", err);
+			return err;
+		}
 	}
 
 	return 0;