drivers: serial: add a dummy driver for vnd,serial

This commit adds a serial dummy driver compatible to vnd,serial.
This is needed that devices can access the uart device in tests
like tests/drivers/build_all/... .

Add myself as codeowner to avoid complicance check failure.

Signed-off-by: Thomas Stranger <thomas.stranger@outlook.com>

drivers/serial/serial_test.c

@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2021, Thomas Stranger
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/*
+ * This is not a real serial driver. It is used to instantiate struct
+ * devices for the "vnd,serial" devicetree compatible used in test code.
+ */
+
+#include <zephyr.h>
+#include <drivers/uart.h>
+
+#define DT_DRV_COMPAT vnd_serial
+
+static int serial_vnd_poll_in(const struct device *dev, unsigned char *c)
+{
+	return -ENOTSUP;
+}
+
+static void serial_vnd_poll_out(const struct device *dev, unsigned char c)
+{
+}
+
+static int serial_vnd_err_check(const struct device *dev)
+{
+	return -ENOTSUP;
+}
+
+#ifdef CONFIG_UART_USE_RUNTIME_CONFIGURE
+static int serial_vnd_configure(const struct device *dev,
+				const struct uart_config *cfg)
+{
+	return -ENOTSUP;
+}
+
+static int serial_vnd_config_get(const struct device *dev,
+				 struct uart_config *cfg)
+{
+	return -ENOTSUP;
+}
+#endif /* CONFIG_UART_USE_RUNTIME_CONFIGURE */
+
+
+static const struct uart_driver_api serial_vnd_api = {
+	.poll_in = serial_vnd_poll_in,
+	.poll_out = serial_vnd_poll_out,
+	.err_check = serial_vnd_err_check,
+#ifdef CONFIG_UART_USE_RUNTIME_CONFIGURE
+	.configure = serial_vnd_configure,
+	.config_get = serial_vnd_config_get,
+#endif /* CONFIG_UART_USE_RUNTIME_CONFIGURE */
+};
+
+static int serial_vnd_init(const struct device *dev)
+{
+	return 0;
+}
+
+#define VND_SERIAL_INIT(n)						\
+	DEVICE_DT_INST_DEFINE(n, &serial_vnd_init, NULL,		\
+			      NULL, NULL, POST_KERNEL,			\
+			      CONFIG_KERNEL_INIT_PRIORITY_DEVICE,	\
+			      &serial_vnd_api);
+
+DT_INST_FOREACH_STATUS_OKAY(VND_SERIAL_INIT)