diff --git a/.github/workflows/module.yml b/.github/workflows/module.yml
index b4d5fcf..a55f133 100644
--- a/.github/workflows/module.yml
+++ b/.github/workflows/module.yml
@@ -44,19 +44,17 @@ jobs:
         # ERROR - qemu_cortex_m3 subsys.greybus.gpio FAILED: Exited with 2
         ${WS}/tools/net-tools/loop-socat.sh &
 
-    # Disabled to du alignment issues on x86_64
-    #- name: GPIO
-    #  timeout-minutes: 5
-    #  run: |
-    #    cd ${ZEPHYR_BASE}
-    #    west build -b native_posix_64 -p always ${GB}/tests/subsys/greybus/gpio
-    #    ./build/zephyr/zephyr.exe
-
-    - name: GPIO (qemu)
+    - name: GPIO
       run: |
         cd ${ZEPHYR_BASE}
         twister -i -p qemu_cortex_m3 -T ${GB}/tests/subsys/greybus/gpio
 
+    - name: GPIO (TLS)
+      timeout-minutes: 5
+      run: |
+        cd ${ZEPHYR_BASE}
+        twister -i -p mps2_an385 -T ${GB}/tests/subsys/greybus/gpio
+
     - name: native_posix_64 [tcp] [gpio]
       run: |
         cd ${ZEPHYR_BASE}
diff --git a/samples/subsys/greybus/net/prj.conf b/samples/subsys/greybus/net/prj.conf
index 963ff23..6c2bb0c 100644
--- a/samples/subsys/greybus/net/prj.conf
+++ b/samples/subsys/greybus/net/prj.conf
@@ -1,16 +1,15 @@
-#CONFIG_MINIMAL_LIBC_MALLOC_ARENA_SIZE=16384
 CONFIG_HEAP_MEM_POOL_SIZE=16384
-CONFIG_NET_HOSTNAME_ENABLE=y
-CONFIG_DNS_SD=y
 CONFIG_NEWLIB_LIBC=y
 
-# Greybus options
+# Greybus options and dependencies
 CONFIG_GREYBUS=y
 CONFIG_GREYBUS_CONTROL=y
+CONFIG_PTHREAD_IPC=y
+CONFIG_PTHREAD_DYNAMIC_STACK=y
+CONFIG_THREAD_NAME=y
 
 # Console options
 CONFIG_CONSOLE_SUBSYS=y
-CONFIG_CONSOLE_GETCHAR=y
 
 # Generic networking options
 CONFIG_NETWORKING=y
@@ -26,6 +25,8 @@ CONFIG_NET_CONNECTION_MANAGER=y
 CONFIG_NET_MAX_CONN=16
 
 # Service advertisement options
+CONFIG_DNS_SD=y
+CONFIG_NET_HOSTNAME_ENABLE=y
 CONFIG_MDNS_RESPONDER=y
 CONFIG_MDNS_RESPONDER_DNS_SD=y
 
diff --git a/subsys/greybus/CMakeLists.txt b/subsys/greybus/CMakeLists.txt
index 1eb965c..fb006cd 100644
--- a/subsys/greybus/CMakeLists.txt
+++ b/subsys/greybus/CMakeLists.txt
@@ -15,6 +15,7 @@ zephyr_library_sources(
 	platform/platform.c
 
 	platform/service.c
+	platform/certificate.c
 
 	platform/bundle.c
 	platform/bus.c
@@ -25,7 +26,7 @@ zephyr_library_sources(
 	qsort.c
 )
 
-if(${CONFIG_GREYBUS_MANIFEST_BUILTIN})
+if(CONFIG_GREYBUS_MANIFEST_BUILTIN)
 
   devicetree_unfixed_h_to_mnfs(
 	${PROJECT_BINARY_DIR}/include/generated/devicetree_unfixed.h
@@ -44,6 +45,30 @@ if(${CONFIG_GREYBUS_MANIFEST_BUILTIN})
     )
 endif()
 
+if(CONFIG_GREYBUS_TLS_BUILTIN)
+  set(gen_dir ${ZEPHYR_BINARY_DIR}/include/generated/)
+
+  if(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_OPTIONAL OR CONFIG_GREYBUS_TLS_CLIENT_VERIFY_REQUIRED)
+    generate_inc_file_for_target(
+      app
+      ${CONFIG_GREYBUS_TLS_BUILTIN_CA_CERT}
+      ${gen_dir}/greybus_tls_builtin_ca_cert.inc
+    )
+  endif()
+
+  generate_inc_file_for_target(
+    app
+    ${CONFIG_GREYBUS_TLS_BUILTIN_SERVER_CERT}
+    ${gen_dir}/greybus_tls_builtin_server_cert.inc
+  )
+
+  generate_inc_file_for_target(
+    app
+    ${CONFIG_GREYBUS_TLS_BUILTIN_SERVER_PRIVKEY}
+    ${gen_dir}/greybus_tls_builtin_server_privkey.inc
+  )
+endif()
+
 zephyr_library_sources_ifdef(CONFIG_GREYBUS_XPORT_TCPIP    platform/transport-tcpip.c)
 zephyr_library_sources_ifdef(CONFIG_GREYBUS_XPORT_UART     platform/transport-uart.c)
 zephyr_library_sources_ifdef(CONFIG_GREYBUS_CONTROL        control-gpb.c)
diff --git a/subsys/greybus/Kconfig b/subsys/greybus/Kconfig
index 1732dcb..7dce701 100644
--- a/subsys/greybus/Kconfig
+++ b/subsys/greybus/Kconfig
@@ -6,10 +6,8 @@
 
 menuconfig GREYBUS
 	bool "Greybus"
-	select PTHREAD_IPC
-	depends on !NET_HOSTNAME_ENABLE || (NET_HOSTNAME_ENABLE && NETWORKING)
-	select THREAD_NAME
-	select PTHREAD_DYNAMIC_STACK
+	depends on PTHREAD_DYNAMIC_STACK
+	depends on PTHREAD_IPC
 	help
 	  This option enables Greybus support.
 
@@ -29,17 +27,113 @@ config GREYBUS_MANIFEST_BUILTIN
 	  data.
 endchoice
 
+config GREYBUS_ENABLE_TLS
+	bool "Use Transport Layer Security (TLS)"
+	depends on TLS_CREDENTIALS
+	help
+	  Choose this option to use industry standard
+	  TLS 1.2 authentication and encryption with
+	  Greybus.
+
+if GREYBUS_ENABLE_TLS
+
+config GREYBUS_TLS_HOSTNAME
+	string "The hostname to use for TLS connections"
+	default "localhost"
+	help
+	  This is the hostname that is presented to TLS clients
+	  as specified in the TLS certificate. Currently there
+	  is not a convenient programmatic way to extract this
+	  information from the TLS certificate at runtime, and
+	  so it must be manually specified.
+
+	  This has nothing to do with the values of
+	  CONFIG_NET_HOSTNAME or CONFIG_NET_HOSTNAME_ENABLE.
+
+choice
+	prompt "How shall the Greybus server verify clients?"
+	default GREYBUS_TLS_CLIENT_VERIFY_REQUIRED
+
+config GREYBUS_TLS_CLIENT_VERIFY_NONE
+	bool "No Client Verification"
+	help
+	  Choose this option so that Greybus never attmpts to verify
+	  client credentials. This option is insecure.
+
+	  If unsure, say N here.
+
+config GREYBUS_TLS_CLIENT_VERIFY_OPTIONAL
+	bool "Optional Client Verification"
+	help
+	  Choose this option so that Greybus only attmpts to verify
+	  client credentials if they provide them. This option is
+	  insecure.
+
+	  If unsure, say N here.
+
+config GREYBUS_TLS_CLIENT_VERIFY_REQUIRED
+	bool "Required Client Verification"
+	help
+	  Choose this option so that Greybus requires clients to present
+	  verifiable credentials. This is the only secure option.
+
+	  If unsure, say Y here.
+endchoice
+
+choice
+	prompt "How will TLS credentials be supplied?"
+	default GREYBUS_TLS_BUILTIN
+
+config GREYBUS_TLS_BUILTIN
+	bool "Compile certificates into the application"
+	help
+	  This option compiles all certificates into the application
+	  by converting the specified files into C arrays.
+	  
+	  Note, security may be compromised if an attacker has
+	  physical access to the device. As such this option is insecure.
+endchoice
+
+if GREYBUS_TLS_BUILTIN
+config GREYBUS_TLS_BUILTIN_CA_CERT
+	string "Path to the CA certificate (for client verification)"
+	depends on GREYBUS_TLS_CLIENT_VERIFY_OPTIONAL || GREYBUS_TLS_CLIENT_VERIFY_REQUIRED
+	default "${ZEPHYR_BASE}/samples/net/sockets/echo_server/src/ca.der"
+	help
+	  The path to the Certificate Signing-Authority certificate
+
+config GREYBUS_TLS_BUILTIN_SERVER_CERT
+	string "Path to the Greybus server certificate"
+	default "${ZEPHYR_BASE}/samples/net/sockets/echo_server/src/server.der"
+	help
+	  The path to the Greybus Server certificate (public key)
+
+config GREYBUS_TLS_BUILTIN_SERVER_PRIVKEY
+	string "Path to the Greybus server private key"
+	default "${ZEPHYR_BASE}/samples/net/sockets/echo_server/src/server_privkey.der"
+	help
+	  The path to the Greybus Server private key
+
+endif # GREYBUS_TLS_BUILTIN
+endif # GREYBUS_ENABLE_TLS
+
 choice
 	prompt "Which transport shall be used for Greybus?"
 	default GREYBUS_XPORT_TCPIP
 
 config GREYBUS_XPORT_TCPIP
 	bool "Use the TCP/IP Transport for Greybus"
+	depends on NET_TCP
+	depends on NET_SOCKETS
+	depends on NET_SOCKETS_POSIX_NAMES
+	depends on !GREYBUS_ENABLE_TLS || (GREYBUS_ENABLE_TLS && NET_SOCKETS_SOCKOPT_TLS)
 	help
 	  This creates a TCP/IP service for Greybus.
 
 config GREYBUS_XPORT_UART
 	bool "Use the UART Transport for Greybus"
+	depends on SERIAL
+	depends on SERIAL_HAS_DRIVER
 	help
 	  This creates a thread for Greybus on a specific UART.
 
@@ -50,114 +144,80 @@ config GREYBUS_XPORT_UART_DEV
 	help
 	  This setting specifies which UART the Greybus service will use.
 endif # GREYBUS_XPORT_UART
-
 endchoice
 
 config GREYBUS_AUDIO
 	bool "Greybus Audio"
-	default n
 	help
 	  Select this for Greybus Audio support.
 
 config GREYBUS_CAMERA
 	bool "Greybus Camera"
-	default n
 	help
 	  Select this for Greybus Camera support.
 
 config GREYBUS_CONTROL
 	bool "Greybus Control"
-	default n
 	help
 	  Select this for a Greybus Control cport.
 
-config GREYBUS_DEBUG
-	bool "Debug Greybus"
-	default n
-	help
-	  Select this to debug Greybus.
-
-config GREYBUS_LOG_FUNC
-	bool "Greybus Debug with Function Name"
-	default n
-	help
-	  Select this option to show the function name in Greybus debug messages.
-
-config GREYBUS_LOG_FILE
-	bool "Greybus Debug with File Name"
-	default y
-	help
-	  Select this option to show the filename and line number in Greybus debug messages.
-
 config GREYBUS_GPIO
 	bool "Greybus GPIO"
-	default n
 	help
 	  Select this for Greybus GPIO support.
 
 config GREYBUS_HID
 	bool "Greybus HID"
-	default n
 	help
 	  Select this for Greybus HID support.
 
 config GREYBUS_I2C
-	bool "Greybus I2C support"
-	default n
+	bool "Greybus I2C"
 	help
 	  Select this for Greybus I2C support.
 
 config GREYBUS_LIGHTS
 	bool "Greybus Lights"
-	default n
 	help
 	  Select this for Greybus Light support.
 
 config GREYBUS_LOOPBACK
 	bool "Greybus Loopback"
-	default n
 	help
 	  Select this for Greybus Loopback support.
 
 config GREYBUS_POWER_SUPPLY
 	bool "Greybus Power Supply"
-	default n
 	help
 	  Select this for Greybus Power Supply support.
 
 config GREYBUS_PWM
 	bool "Greybus PWM"
-	default n
 	help
 	  Select this for Greybus Pulse Width Modulation support.
 
 config GREYBUS_SDIO
 	bool "Greybus SDIO"
-	default n
 	help
 	  Select this for Greybus Secure Digital IO support.
 
 config GREYBUS_SPI
 	bool "Greybus SPI"
-	default n
 	help
 	  Select this for Greybus Serial Peripheral Interface support.
 
 config GREYBUS_UART
 	bool "Greybus UART"
-	default n
 	help
 	  Select this for Greybus Universal Asynchronous Receiver Transmitter support.
 
 config GREYBUS_USB
 	bool "Greybus USB"
-	default n
 	help
 	  Select this for Greybus Universal Serial Bus support.
 
 config GREYBUS_VIBRATOR
 	bool "Greybus Vibrator"
-	default n
 	help
 	  Select this for Greybus Vibrator support.
 
@@ -197,7 +257,7 @@ config GREYBUS_CPORT_INIT_PRIORITY
 	  Greybus cport init priority to ensure device initialization order.
 
 module = GREYBUS
-module-str = gb
+module-str = Greybus
 source "subsys/logging/Kconfig.template.log_config"
 
 endif # GREYBUS
diff --git a/subsys/greybus/greybus-core.c b/subsys/greybus/greybus-core.c
index a2e2b32..80f77ff 100644
--- a/subsys/greybus/greybus-core.c
+++ b/subsys/greybus/greybus-core.c
@@ -53,9 +53,15 @@ extern int pthread_setname_np(pthread_t thread, const char *name);
 #define DEFAULT_STACK_SIZE PTHREAD_STACK_MIN
 
 #else
+
 #include <posix/pthread.h>
 #include <posix/semaphore.h>
+
 #define DEFAULT_STACK_SIZE      CONFIG_PTHREAD_DYNAMIC_STACK_DEFAULT_SIZE
+
+void qsort(void *base, size_t nmemb, size_t size,
+                  int (*compar)(const void *, const void *));
+
 #endif
 
 #include <stdio.h>
@@ -553,6 +559,7 @@ int _gb_register_driver(unsigned int cport, int bundle_id,
     pthread_attr_t thread_attr;
     pthread_attr_t *thread_attr_ptr = &thread_attr;
     struct gb_bundle *bundle;
+	char thread_name[CONFIG_THREAD_MAX_NAME_LEN];
     int retval;
 
     LOG_DBG("Registering Greybus driver on CP%u", cport);
@@ -643,9 +650,8 @@ int _gb_register_driver(unsigned int cport, int bundle_id,
         goto pthread_create_error;
     }
 
-	char thread_name[CONFIG_THREAD_MAX_NAME_LEN];
-	(void)snprintf(thread_name, sizeof(thread_name), "greybus[%u]", cport);
-	(void)pthread_setname_np(g_cport[cport].thread, thread_name);
+	snprintf(thread_name, sizeof(thread_name), "greybus[%u]", cport);
+	pthread_setname_np(g_cport[cport].thread, thread_name);
 
     pthread_attr_destroy(&thread_attr);
     thread_attr_ptr = NULL;
diff --git a/subsys/greybus/platform/certificate.c b/subsys/greybus/platform/certificate.c
new file mode 100644
index 0000000..295b5d3
--- /dev/null
+++ b/subsys/greybus/platform/certificate.c
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2020 Friedt Professional Engineering Services, Inc
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <zephyr.h>
+#include "certificate.h"
+
+#include <logging/log.h>
+LOG_MODULE_REGISTER(greybus_tls, CONFIG_GREYBUS_LOG_LEVEL);
+
+#ifdef CONFIG_GREYBUS_TLS_BUILTIN
+#if defined(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_OPTIONAL) \
+		|| defined(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_REQUIRED)
+static const unsigned char greybus_tls_builtin_ca_cert[] = {
+#include "greybus_tls_builtin_ca_cert.inc"
+};
+#else /* CONFIG_GREYBUS_TLS_TLS_CLIENT_VERIFY.. */
+#define greybus_tls_builtin_ca_cert NULL
+#endif /* CONFIG_GREYBUS_TLS_TLS_CLIENT_VERIFY.. */
+
+static const unsigned char greybus_tls_builtin_server_cert[] = {
+#include "greybus_tls_builtin_server_cert.inc"
+};
+
+static const unsigned char greybus_tls_builtin_server_privkey[] = {
+#include "greybus_tls_builtin_server_privkey.inc"
+};
+#else
+#define greybus_tls_builtin_ca_cert NULL
+#define greybus_tls_builtin_server_cert NULL
+#define greybus_tls_builtin_server_privkey NULL
+#endif /* GREYBUS_TLS_BUILTIN */
+
+int greybus_tls_init(void)
+{
+	if (IS_ENABLED(CONFIG_GREYBUS_TLS_BUILTIN)) {
+		int r;
+
+		LOG_INF("Initializing built-in certificates");
+
+		if (IS_ENABLED(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_OPTIONAL)
+			|| IS_ENABLED(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_REQUIRED)) {
+			LOG_DBG("Adding CA Certificate (%zu bytes)", sizeof(greybus_tls_builtin_ca_cert));
+			r = tls_credential_add(GB_TLS_CA_CERT_TAG, TLS_CREDENTIAL_CA_CERTIFICATE,
+					greybus_tls_builtin_ca_cert, sizeof(greybus_tls_builtin_ca_cert));
+			if (r < 0) {
+				LOG_ERR("Failed to add CA Certificate: %d", r);
+				return r;
+			}
+		}
+
+		LOG_DBG("Adding Server Certificate (Public Key) (%zu bytes)", sizeof(greybus_tls_builtin_server_cert));
+		r = tls_credential_add(GB_TLS_SERVER_CERT_TAG, TLS_CREDENTIAL_SERVER_CERTIFICATE,
+				greybus_tls_builtin_server_cert, sizeof(greybus_tls_builtin_server_cert));
+		if (r < 0) {
+			LOG_ERR("Failed to add Server Certificate (Public Key): %d", r);
+			return r;
+		}
+
+		LOG_DBG("Adding Server Certificate (Private Key) (%zu bytes)", sizeof(greybus_tls_builtin_server_privkey));
+		r = tls_credential_add(GB_TLS_SERVER_CERT_TAG, TLS_CREDENTIAL_PRIVATE_KEY,
+				greybus_tls_builtin_server_privkey, sizeof(greybus_tls_builtin_server_privkey));
+		if (r < 0) {
+			LOG_ERR("Failed to add Server Certificate (Private Key): %d", r);
+			return r;
+		}
+	}
+
+	return 0;
+}
diff --git a/subsys/greybus/platform/certificate.h b/subsys/greybus/platform/certificate.h
new file mode 100644
index 0000000..ed120fd
--- /dev/null
+++ b/subsys/greybus/platform/certificate.h
@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2020 Friedt Professional Engineering Services, Inc
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef SUBSYS_GREYBUS_PLATFORM_CERTIFICATE_H_
+#define SUBSYS_GREYBUS_PLATFORM_CERTIFICATE_H_
+
+#include <net/tls_credentials.h>
+
+enum greybus_tls_certificate_type {
+	GB_TLS_CA_CERT_TAG,
+	GB_TLS_SERVER_CERT_TAG,
+	GB_TLS_CLIENT_CERT_TAG,
+};
+
+int greybus_tls_init(void);
+
+#endif /* SUBSYS_GREYBUS_PLATFORM_CERTIFICATE_H_ */
diff --git a/subsys/greybus/platform/i2c.c b/subsys/greybus/platform/i2c.c
index 94c4f56..8c9fd89 100644
--- a/subsys/greybus/platform/i2c.c
+++ b/subsys/greybus/platform/i2c.c
@@ -89,10 +89,10 @@ static int greybus_i2c_control_init(const struct device *dev) {
         static struct greybus_i2c_control_data									\
 			greybus_i2c_control_data_##_num;									\
         																		\
-        DEVICE_INIT(i2c_i2c_control_##_num, "GBI2C_" #_num,					\
-                            greybus_i2c_control_init,					\
+        DEVICE_DT_INST_DEFINE(_num,					\
+                            greybus_i2c_control_init, NULL,				\
 							&greybus_i2c_control_data_##_num,					\
                             &greybus_i2c_control_config_##_num, POST_KERNEL,	\
-                            CONFIG_GREYBUS_CPORT_INIT_PRIORITY);
+                            CONFIG_GREYBUS_CPORT_INIT_PRIORITY, NULL);
 
 DT_INST_FOREACH_STATUS_OKAY(DEFINE_GREYBUS_I2C_CONTROL);
diff --git a/subsys/greybus/platform/service.c b/subsys/greybus/platform/service.c
index 07c3fb2..5e03ee4 100644
--- a/subsys/greybus/platform/service.c
+++ b/subsys/greybus/platform/service.c
@@ -19,13 +19,11 @@ LOG_MODULE_REGISTER(greybus_service, CONFIG_GREYBUS_LOG_LEVEL);
 
 #include "transport.h"
 #include "manifest.h"
+#include "certificate.h"
 
 /* Currently only one greybus instance is supported */
 #define GREYBUS_BUS_NAME "GREYBUS_0"
 
-/* Deferred init of some DT nodes required - see defer_init.c */
-extern int gb_service_deferred_init(void);
-
 static struct gb_transport_backend *xport;
 static size_t num_cports;
 
@@ -52,12 +50,19 @@ static int greybus_service_init(const struct device *bus)
 		return -EALREADY;
 	}
 
+	r = greybus_tls_init();
+	if (r < 0) {
+		LOG_ERR("gb_tls_init() failed: %d", r);
+		goto out;
+	}
+
 	LOG_DBG("Greybus initializing..");
 
 	bus = device_get_binding(GREYBUS_BUS_NAME);
 	if (NULL == bus) {
 		r = -ENODEV;
 		LOG_ERR("failed to get " GREYBUS_BUS_NAME " device");
+		r = -ENODEV;
 		goto out;
 	}
 
@@ -111,6 +116,7 @@ static int greybus_service_init(const struct device *bus)
     if (cports != NULL) {
         free(cports);
     }
+
     return r;
 }
 
diff --git a/subsys/greybus/platform/transport-tcpip.c b/subsys/greybus/platform/transport-tcpip.c
index 0c8958e..33b00d0 100644
--- a/subsys/greybus/platform/transport-tcpip.c
+++ b/subsys/greybus/platform/transport-tcpip.c
@@ -26,11 +26,21 @@
 #include <sys/socket.h>
 #include <unistd.h>
 
-/* For some reason, not declared even with _GNU_SOURCE */
-extern int pthread_setname_np(pthread_t thread, const char *name);
+/*
+ * There seem to be a number of conflicts between Linux and
+ * Zephyr headers for networking things. So a few things are
+ * defined manually.
+ */
+#define IPPROTO_TLS_1_2 258
+#define TLS_SEC_TAG_LIST 1
+#define TLS_HOSTNAME 2
+#define TLS_PEER_VERIFY 5
+#define TLS_PEER_VERIFY_NONE 0
+#define TLS_PEER_VERIFY_OPTIONAL 1
+#define TLS_PEER_VERIFY_REQUIRED 2
+
+typedef int sec_tag_t;
 
-/* For some reason, including <net/net_ip.h> breaks everything
- * I only need these */
 static inline struct sockaddr_in *net_sin(struct sockaddr *sa)
 {
 	return (struct sockaddr_in *)sa;
@@ -41,6 +51,9 @@ static inline struct sockaddr_in6 *net_sin6(struct sockaddr *sa)
 	return (struct sockaddr_in6 *)sa;
 }
 
+/* For some reason, not declared even with _GNU_SOURCE */
+extern int pthread_setname_np(pthread_t thread, const char *name);
+
 extern int usleep(useconds_t usec);
 
 #else
@@ -68,6 +81,11 @@ int usleep(useconds_t usec) {
 LOG_MODULE_REGISTER(greybus_transport_tcpip, CONFIG_GREYBUS_LOG_LEVEL);
 
 #include "transport.h"
+#include "certificate.h"
+
+#ifndef CONFIG_GREYBUS_ENABLE_TLS
+#define CONFIG_GREYBUS_TLS_HOSTNAME ""
+#endif
 
 /* Based on UniPro, from Linux */
 #define CPORT_ID_MAX 4095
@@ -75,6 +93,12 @@ LOG_MODULE_REGISTER(greybus_transport_tcpip, CONFIG_GREYBUS_LOG_LEVEL);
 #define GB_TRANSPORT_TCPIP_BASE_PORT 4242
 #define GB_TRANSPORT_TCPIP_BACKLOG 10
 
+#ifdef CONFIG_GREYBUS_ENABLE_TLS
+#define XPORT "TLS"
+#else
+#define XPORT "TCP/IP"
+#endif
+
 enum fd_context_type {
 	FD_CONTEXT_SERVER = 1,
 	FD_CONTEXT_CLIENT = 2,
@@ -89,8 +113,13 @@ struct fd_context {
     enum fd_context_type type;
 };
 
+#ifdef CONFIG_GREYBUS_ENABLE_TLS
+DNS_SD_REGISTER_TCP_SERVICE(gb_service_advertisement, CONFIG_NET_HOSTNAME,
+	"_greybuss", "local", DNS_SD_EMPTY_TXT, GB_TRANSPORT_TCPIP_BASE_PORT);
+#else /* CONFIG_GREYBUS_ENABLE_TLS */
 DNS_SD_REGISTER_TCP_SERVICE(gb_service_advertisement, CONFIG_NET_HOSTNAME,
 	"_greybus", "local", DNS_SD_EMPTY_TXT, GB_TRANSPORT_TCPIP_BASE_PORT);
+#endif /* CONFIG_GREYBUS_ENABLE_TLS */
 
 static sys_dlist_t fd_list;
 static pthread_mutex_t fd_list_mutex;
@@ -553,6 +582,7 @@ static int sendMessage(int fd, struct gb_operation_hdr *msg)
 	for (remaining = sys_le16_to_cpu(msg->size), offset = 0, written = 0;
 	     remaining; remaining -= written, offset += written, written = 0) {
 
+		LOG_DBG("gb: send(%d, %p, %zu, 0)", fd, &((uint8_t *)msg)[offset], remaining);
 		r = send(fd, &((uint8_t *)msg)[offset], remaining, 0);
 
 		if (r < 0) {
@@ -656,9 +686,15 @@ static int netsetup(size_t num_cports)
 	const int yes = true;
 	int family;
 	uint16_t *port;
+	int proto = IPPROTO_TCP;
 	struct sockaddr sa;
 	socklen_t sa_len;
 
+	if (IS_ENABLED(CONFIG_GREYBUS_TLS_BUILTIN)) {
+		proto = IPPROTO_TLS_1_2;
+	}
+
+	memset(&sa, 0, sizeof(sa));
 	if (IS_ENABLED(CONFIG_NET_IPV6)) {
 		family = AF_INET6;
 		net_sin6(&sa)->sin6_family = AF_INET6;
@@ -678,7 +714,7 @@ static int netsetup(size_t num_cports)
 	*port = htons(GB_TRANSPORT_TCPIP_BASE_PORT);
 
     for(i = 0; i < num_cports; ++i) {
-        fd = socket(family, SOCK_STREAM, 0);
+        fd = socket(family, SOCK_STREAM, proto);
         if (fd == -1) {
             LOG_ERR("socket: %d", errno);
             return -errno;
@@ -692,10 +728,50 @@ static int netsetup(size_t num_cports)
 
         r = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes));
         if (-1 == r) {
-            LOG_ERR("setsockopt: %d", errno);
+        	LOG_ERR("setsockopt: Failed to set SO_REUSEADDR (%d)", errno);
             return -errno;
         }
 
+		if (IS_ENABLED(CONFIG_GREYBUS_ENABLE_TLS)) {
+			static const sec_tag_t sec_tag_opt[] = {
+#if defined(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_OPTIONAL) \
+	|| defined(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_REQUIRED)
+				GB_TLS_CA_CERT_TAG,
+#endif
+				GB_TLS_SERVER_CERT_TAG,
+			};
+
+			r = setsockopt(fd, SOL_TLS, TLS_SEC_TAG_LIST, sec_tag_opt, sizeof(sec_tag_opt));
+			if (-1 == r) {
+				LOG_ERR("setsockopt: Failed to set SEC_TAG_LIST (%d)", errno);
+				return -errno;
+			}
+
+			r = setsockopt(fd, SOL_TLS, TLS_HOSTNAME, CONFIG_GREYBUS_TLS_HOSTNAME,
+				strlen(CONFIG_GREYBUS_TLS_HOSTNAME));
+			if (-1 == r) {
+				LOG_ERR("setsockopt: Failed to set TLS_HOSTNAME (%d)", errno);
+				return -errno;
+			}
+
+			/* default to no client verification */
+			int verify = TLS_PEER_VERIFY_NONE;
+
+			if (IS_ENABLED(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_OPTIONAL)) {
+				verify = TLS_PEER_VERIFY_OPTIONAL;
+			}
+
+			if (IS_ENABLED(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_REQUIRED)) {
+				verify = TLS_PEER_VERIFY_REQUIRED;
+			}
+
+			r = setsockopt(fd, SOL_TLS, TLS_PEER_VERIFY, &verify, sizeof(verify));
+			if (-1 == r) {
+				LOG_ERR("setsockopt: Failed to set TLS_PEER_VERIFY (%d)", errno);
+				return -errno;
+			}
+		}
+
     	*port = htons(GB_TRANSPORT_TCPIP_BASE_PORT + i);
         r = bind(fd, &sa, sa_len);
         if (-1 == r) {
@@ -709,7 +785,7 @@ static int netsetup(size_t num_cports)
             return -errno;
         }
 
-        LOG_INF("CPort %zu mapped to TCP/IP port %zu",
+        LOG_INF("CPort %zu mapped to " XPORT " port %zu",
 			i, GB_TRANSPORT_TCPIP_BASE_PORT + i);
     }
 
@@ -721,7 +797,7 @@ struct gb_transport_backend *gb_transport_backend_init(size_t num_cports) {
     int r;
     struct gb_transport_backend *ret = NULL;
 
-	LOG_DBG("Greybus TCP/IP Transport initializing..");
+	LOG_DBG("Greybus " XPORT " Transport initializing..");
 
 	pthread_mutex_init(&fd_list_mutex, NULL);
 	sys_dlist_init(&fd_list);
@@ -736,17 +812,18 @@ struct gb_transport_backend *gb_transport_backend_init(size_t num_cports) {
         goto cleanup;
     }
 
-	r = pthread_create(&accept_thread, NULL, service_thread, NULL);
-	if (r != 0) {
+    r = pthread_create(&accept_thread, NULL, service_thread, NULL);
+    if (r != 0) {
 		LOG_ERR("pthread_create: %d", r);
 		goto cleanup;
 	}
 
-	(void)pthread_setname_np(accept_thread, "greybus");
+	pthread_setname_np(accept_thread, "greybus");
 
     ret = (struct gb_transport_backend *)&gb_xport;
 
-	LOG_INF("Greybus TCP/IP Transport initialized");
+	LOG_INF("Greybus " XPORT " Transport initialized");
+
 	goto out;
 
 cleanup:
diff --git a/subsys/greybus/platform/transport-uart.c b/subsys/greybus/platform/transport-uart.c
index 2948aa5..d4bedfd 100644
--- a/subsys/greybus/platform/transport-uart.c
+++ b/subsys/greybus/platform/transport-uart.c
@@ -30,7 +30,7 @@ LOG_MODULE_REGISTER(greybus_xsport_uart, CONFIG_GREYBUS_LOG_LEVEL);
 static int sendMessage(struct device *dev, struct gb_operation_hdr *msg);
 static void uart_work_fn(struct k_work *work);
 
-static struct device *uart_dev;
+static const struct device *uart_dev;
 
 RING_BUF_DECLARE(uart_rb, UART_RB_SIZE);
 static K_WORK_DEFINE(uart_work, uart_work_fn);
diff --git a/tests/subsys/greybus/gpio/CMakeLists.txt b/tests/subsys/greybus/gpio/CMakeLists.txt
index 112ae66..3a18271 100644
--- a/tests/subsys/greybus/gpio/CMakeLists.txt
+++ b/tests/subsys/greybus/gpio/CMakeLists.txt
@@ -6,5 +6,36 @@ cmake_minimum_required(VERSION 3.13.1)
 find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
 project(greybus)
 
+if(CONFIG_GREYBUS_ENABLE_TLS)
+
+  set(gen_dir ${ZEPHYR_BINARY_DIR}/include/generated/)
+
+  if(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_OPTIONAL OR CONFIG_GREYBUS_TLS_CLIENT_VERIFY_REQUIRED)
+
+    generate_inc_file_for_target(
+      app
+      ${ZEPHYR_BASE}/samples/net/sockets/echo_server/src/server.der
+      ${gen_dir}/greybus_client.inc
+    )
+
+    generate_inc_file_for_target(
+      app
+      ${ZEPHYR_BASE}/samples/net/sockets/echo_server/src/server_privkey.der
+      ${gen_dir}/greybus_client_privkey.inc
+    )
+
+  else()
+
+    # if client verification is not needed, then the client needs to
+    # load these credentials
+    generate_inc_file_for_target(
+      app
+      ${ZEPHYR_BASE}/samples/net/sockets/echo_server/src/ca.der
+      ${gen_dir}/greybus_ca.inc
+    )
+
+  endif()
+endif()
+
 FILE(GLOB_RECURSE app_sources src/*.c)
 target_sources(app PRIVATE ${app_sources})
diff --git a/tests/subsys/greybus/gpio/boards/mps2_an385.conf b/tests/subsys/greybus/gpio/boards/mps2_an385.conf
new file mode 100644
index 0000000..5b180b1
--- /dev/null
+++ b/tests/subsys/greybus/gpio/boards/mps2_an385.conf
@@ -0,0 +1,14 @@
+# Copyright (c) 2020 Friedt Professional Engineering Services, Inc
+# SPDX-License-Identifier: BSD-3-Clause
+
+# the qemu gpio driver does not seemt to handle tests properly
+CONFIG_GPIO_EMUL=y
+
+# for a loopback connection, ipv4 is fine
+CONFIG_NET_IPV6=n
+CONFIG_NET_CONFIG_NEED_IPV6=n
+
+# Networking Options
+CONFIG_NET_LOOPBACK=y
+CONFIG_NET_L2_DUMMY=y
+CONFIG_TEST_RANDOM_GENERATOR=y
diff --git a/tests/subsys/greybus/gpio/boards/mps2_an385.overlay b/tests/subsys/greybus/gpio/boards/mps2_an385.overlay
new file mode 100644
index 0000000..8d2c3ed
--- /dev/null
+++ b/tests/subsys/greybus/gpio/boards/mps2_an385.overlay
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2020 Friedt Professional Engineering Services, Inc
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+ #include <dt-bindings/greybus/greybus.h>
+
+/ {
+	resources {
+		compatible = "test,greybus-gpio";
+		out-gpios = <&gpio42 0 0>;
+		in-gpios = <&gpio42 1 0>;
+	};
+
+	greybus0: greybus0 {
+		compatible = "zephyr,greybus";
+		label = "GREYBUS_0";
+		greybus;
+	};
+	
+    gpio42: gpio@4200 {
+        status = "okay";
+        compatible = "zephyr,gpio-emul";
+        reg = <0x4200 0x4>;
+        label = "GPIO_42";
+        rising-edge;
+        falling-edge;
+        high-level;
+        low-level;
+        gpio-controller;
+        #gpio-cells = <2>;
+    };
+};
+
+&gpio42 {
+	status = "okay";
+	ngpios = <2>;
+};
+
+&greybus0 {
+	label = "GREYBUS_0";
+	status = "okay";
+	/* defaults in effect, so this isn't necessary */
+	version-major = <GREYBUS_VERSION_MAJOR>;
+	version-minor = <GREYBUS_VERSION_MINOR>;
+
+	gbstring1: gbstring1 {
+		label = "GBSTRING_1";
+		status = "okay";
+		compatible = "zephyr,greybus-string";
+		id = <1>;
+		greybus-string = "Zephyr Project RTOS";
+	};
+
+	gbstring2: gbstring2 {
+		label = "GBSTRING_2";
+		status = "okay";
+		compatible = "zephyr,greybus-string";
+		id = <2>;
+		greybus-string = "Greybus Service Sample Application";
+	};
+
+	gbinterface0 {
+		label = "GBINTERFACE_0";
+		status = "okay";
+		compatible = "zephyr,greybus-interface";
+		vendor-string-id = <&gbstring1>;
+		product-string-id = <&gbstring2>;
+		greybus-interface;
+	};
+
+	gbbundle0 {
+		label = "GBBUNDLE_0";
+		status = "okay";
+		compatible = "zephyr,greybus-bundle";
+		greybus-bundle;
+		/* Control Bundle 0
+		 * Note: control bundle 0 and control cport 0 are optional
+		 * Since instance numbers automatically begin at 0, the id
+		 * is a mandatory field for bundles and cports.
+		 */
+		id = <CONTROL_BUNDLE_ID>;
+		bundle-class = <BUNDLE_CLASS_CONTROL>;
+
+		gbcontrol0 {
+			label = "GBCONTROL_0";
+			status = "okay";
+			compatible = "zephyr,greybus-control";
+			greybus-controller;
+			/* Control CPort 0
+			 * Note: control bundle 0 and control cport 0 are optional
+			 * Since instance numbers automatically begin at 0, the id
+			 * is a mandatory field for bundles and cports.
+			 */
+			id = <CONTROL_CPORT_ID>;
+			cport-protocol = <CPORT_PROTOCOL_CONTROL>; 
+		};
+	};
+	
+	gbbundle1 {
+		label = "GBBUNDLE_1";
+		status = "okay";
+		compatible = "zephyr,greybus-bundle";
+		greybus-bundle;
+		id = <1>;
+		bundle-class = <BUNDLE_CLASS_BRIDGED_PHY>;		
+				
+		gbgpio0 {
+			label = "GBGPIO_0";
+			status = "okay";
+			compatible = "zephyr,greybus-gpio-controller";
+			greybus-gpio-controller = <&gpio42>;
+			id = <1>;
+			cport-protocol = <CPORT_PROTOCOL_GPIO>;
+		};
+	};
+};
diff --git a/tests/subsys/greybus/gpio/boards/qemu_cortex_m3.conf b/tests/subsys/greybus/gpio/boards/qemu_cortex_m3.conf
index 0a1ba81..5b180b1 100644
--- a/tests/subsys/greybus/gpio/boards/qemu_cortex_m3.conf
+++ b/tests/subsys/greybus/gpio/boards/qemu_cortex_m3.conf
@@ -12,5 +12,3 @@ CONFIG_NET_CONFIG_NEED_IPV6=n
 CONFIG_NET_LOOPBACK=y
 CONFIG_NET_L2_DUMMY=y
 CONFIG_TEST_RANDOM_GENERATOR=y
-CONFIG_NET_CONFIG_MY_IPV4_ADDR="127.0.0.1"
-CONFIG_NET_CONFIG_MY_IPV6_ADDR="::1"
diff --git a/tests/subsys/greybus/gpio/boards/qemu_x86_64.conf b/tests/subsys/greybus/gpio/boards/qemu_x86_64.conf
new file mode 100644
index 0000000..5b180b1
--- /dev/null
+++ b/tests/subsys/greybus/gpio/boards/qemu_x86_64.conf
@@ -0,0 +1,14 @@
+# Copyright (c) 2020 Friedt Professional Engineering Services, Inc
+# SPDX-License-Identifier: BSD-3-Clause
+
+# the qemu gpio driver does not seemt to handle tests properly
+CONFIG_GPIO_EMUL=y
+
+# for a loopback connection, ipv4 is fine
+CONFIG_NET_IPV6=n
+CONFIG_NET_CONFIG_NEED_IPV6=n
+
+# Networking Options
+CONFIG_NET_LOOPBACK=y
+CONFIG_NET_L2_DUMMY=y
+CONFIG_TEST_RANDOM_GENERATOR=y
diff --git a/tests/subsys/greybus/gpio/boards/qemu_x86_64.overlay b/tests/subsys/greybus/gpio/boards/qemu_x86_64.overlay
new file mode 100644
index 0000000..8d2c3ed
--- /dev/null
+++ b/tests/subsys/greybus/gpio/boards/qemu_x86_64.overlay
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2020 Friedt Professional Engineering Services, Inc
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+ #include <dt-bindings/greybus/greybus.h>
+
+/ {
+	resources {
+		compatible = "test,greybus-gpio";
+		out-gpios = <&gpio42 0 0>;
+		in-gpios = <&gpio42 1 0>;
+	};
+
+	greybus0: greybus0 {
+		compatible = "zephyr,greybus";
+		label = "GREYBUS_0";
+		greybus;
+	};
+	
+    gpio42: gpio@4200 {
+        status = "okay";
+        compatible = "zephyr,gpio-emul";
+        reg = <0x4200 0x4>;
+        label = "GPIO_42";
+        rising-edge;
+        falling-edge;
+        high-level;
+        low-level;
+        gpio-controller;
+        #gpio-cells = <2>;
+    };
+};
+
+&gpio42 {
+	status = "okay";
+	ngpios = <2>;
+};
+
+&greybus0 {
+	label = "GREYBUS_0";
+	status = "okay";
+	/* defaults in effect, so this isn't necessary */
+	version-major = <GREYBUS_VERSION_MAJOR>;
+	version-minor = <GREYBUS_VERSION_MINOR>;
+
+	gbstring1: gbstring1 {
+		label = "GBSTRING_1";
+		status = "okay";
+		compatible = "zephyr,greybus-string";
+		id = <1>;
+		greybus-string = "Zephyr Project RTOS";
+	};
+
+	gbstring2: gbstring2 {
+		label = "GBSTRING_2";
+		status = "okay";
+		compatible = "zephyr,greybus-string";
+		id = <2>;
+		greybus-string = "Greybus Service Sample Application";
+	};
+
+	gbinterface0 {
+		label = "GBINTERFACE_0";
+		status = "okay";
+		compatible = "zephyr,greybus-interface";
+		vendor-string-id = <&gbstring1>;
+		product-string-id = <&gbstring2>;
+		greybus-interface;
+	};
+
+	gbbundle0 {
+		label = "GBBUNDLE_0";
+		status = "okay";
+		compatible = "zephyr,greybus-bundle";
+		greybus-bundle;
+		/* Control Bundle 0
+		 * Note: control bundle 0 and control cport 0 are optional
+		 * Since instance numbers automatically begin at 0, the id
+		 * is a mandatory field for bundles and cports.
+		 */
+		id = <CONTROL_BUNDLE_ID>;
+		bundle-class = <BUNDLE_CLASS_CONTROL>;
+
+		gbcontrol0 {
+			label = "GBCONTROL_0";
+			status = "okay";
+			compatible = "zephyr,greybus-control";
+			greybus-controller;
+			/* Control CPort 0
+			 * Note: control bundle 0 and control cport 0 are optional
+			 * Since instance numbers automatically begin at 0, the id
+			 * is a mandatory field for bundles and cports.
+			 */
+			id = <CONTROL_CPORT_ID>;
+			cport-protocol = <CPORT_PROTOCOL_CONTROL>; 
+		};
+	};
+	
+	gbbundle1 {
+		label = "GBBUNDLE_1";
+		status = "okay";
+		compatible = "zephyr,greybus-bundle";
+		greybus-bundle;
+		id = <1>;
+		bundle-class = <BUNDLE_CLASS_BRIDGED_PHY>;		
+				
+		gbgpio0 {
+			label = "GBGPIO_0";
+			status = "okay";
+			compatible = "zephyr,greybus-gpio-controller";
+			greybus-gpio-controller = <&gpio42>;
+			id = <1>;
+			cport-protocol = <CPORT_PROTOCOL_GPIO>;
+		};
+	};
+};
diff --git a/tests/subsys/greybus/gpio/prj.conf b/tests/subsys/greybus/gpio/prj.conf
index 408578f..e6b8b4d 100644
--- a/tests/subsys/greybus/gpio/prj.conf
+++ b/tests/subsys/greybus/gpio/prj.conf
@@ -1,54 +1,43 @@
+CONFIG_NET_TEST=y
 CONFIG_ZTEST=y
 CONFIG_ZTEST_STACKSIZE=2048
+CONFIG_HEAP_MEM_POOL_SIZE=8192
 
 CONFIG_NEWLIB_LIBC=y
-CONFIG_HEAP_MEM_POOL_SIZE=8192
 
-CONFIG_GPIO=y
+# Greybus options and dependencies
+CONFIG_PTHREAD_IPC=y
+CONFIG_PTHREAD_DYNAMIC_STACK=y
+CONFIG_THREAD_NAME=y
 CONFIG_GREYBUS=y
-#CONFIG_GB_LOG_LEVEL=4
-#CONFIG_GREYBUS_AUDIO=y
-#CONFIG_GREYBUS_CAMERA=y
 CONFIG_GREYBUS_CONTROL=y
+CONFIG_GPIO=y
 CONFIG_GREYBUS_GPIO=y
-#CONFIG_GREYBUS_DEBUG=y
-#CONFIG_GREYBUS_HID=y
-#CONFIG_GREYBUS_I2C=y
-#CONFIG_GREYBUS_LIGHTS=y
-#CONFIG_GREYBUS_LOOPBACK=y
-#CONFIG_GREYBUS_POWER_SUPPLY=y
-#CONFIG_GREYBUS_PWM=y
-#CONFIG_GREYBUS_SDIO=y
-#CONFIG_GREYBUS_SPI=y
-#CONFIG_GREYBUS_UART=y
-#CONFIG_GREYBUS_USB=y
-#CONFIG_GREYBUS_VIBRATOR=y
-CONFIG_CONSOLE_SUBSYS=y
-#CONFIG_CONSOLE_GETCHAR=y
 
 # Generic networking options
 CONFIG_NET_HOSTNAME_ENABLE=y
 CONFIG_NETWORKING=y
-CONFIG_NET_UDP=y
+CONFIG_NET_UDP=n
 CONFIG_NET_TCP=y
-CONFIG_NET_IPV6=y
+CONFIG_NET_IPV6=n
 CONFIG_NET_IPV4=y
 CONFIG_NET_SOCKETS=y
 CONFIG_NET_SOCKETS_POSIX_NAMES=y
-CONFIG_POSIX_MAX_FDS=16
+CONFIG_POSIX_MAX_FDS=10
 CONFIG_NET_SOCKETS_POLL_MAX=16
+CONFIG_NET_STATISTICS=y
 
 # Kernel options
-CONFIG_MAIN_STACK_SIZE=1024
-#CONFIG_ENTROPY_GENERATOR=y
+CONFIG_MAIN_STACK_SIZE=2048
 CONFIG_TEST_RANDOM_GENERATOR=y
 CONFIG_INIT_STACKS=y
 
-# Logging
-CONFIG_NET_LOG=y
-CONFIG_LOG=y
-CONFIG_NET_STATISTICS=y
-CONFIG_PRINTK=y
+# Logging / Debugging
+#CONFIG_NET_LOG=y
+#CONFIG_NET_SOCKETS_LOG_LEVEL_DBG=y
+#CONFIG_GREYBUS_LOG_LEVEL_DBG=y
+#CONFIG_MBEDTLS_DEBUG=y
+#CONFIG_MBEDTLS_DEBUG_LEVEL=4
 
 # Network buffers
 CONFIG_NET_PKT_RX_COUNT=16
@@ -57,21 +46,23 @@ CONFIG_NET_BUF_RX_COUNT=16
 CONFIG_NET_BUF_TX_COUNT=16
 CONFIG_NET_CONTEXT_NET_PKT_POOL=y
 
-# IP address options
-CONFIG_NET_IF_UNICAST_IPV6_ADDR_COUNT=3
-CONFIG_NET_IF_MCAST_IPV6_ADDR_COUNT=4
-CONFIG_NET_MAX_CONTEXTS=10
+# TLS Options
+#CONFIG_GREYBUS_ENABLE_TLS=y
+#CONFIG_GREYBUS_TLS_BUILTIN=y
+#CONFIG_NET_SOCKETS_SOCKOPT_TLS=y
+#CONFIG_TLS_CREDENTIALS=y
+#CONFIG_NET_PKT_RX_COUNT=64
+#CONFIG_NET_PKT_TX_COUNT=64
+#CONFIG_NET_BUF_RX_COUNT=64
+#CONFIG_NET_BUF_TX_COUNT=64
+#CONFIG_NET_SOCKETS_TLS_MAX_CONTEXTS=10
+#CONFIG_ZTEST_STACKSIZE=8192
+#CONFIG_PTHREAD_DYNAMIC_STACK_DEFAULT_SIZE=8192
+#CONFIG_HEAP_MEM_POOL_SIZE=16384
 
-# Network shell
-CONFIG_NET_SHELL=y
-CONFIG_SHELL=y
+# IP address options
+CONFIG_NET_MAX_CONTEXTS=16
 
 # Network application options and configuration
 CONFIG_NET_CONFIG_SETTINGS=y
-CONFIG_NET_CONFIG_MY_IPV6_ADDR="2001:db8::1"
-CONFIG_NET_CONFIG_PEER_IPV6_ADDR="2001:db8::2"
 CONFIG_NET_CONFIG_MY_IPV4_ADDR="192.0.2.1"
-CONFIG_NET_CONFIG_PEER_IPV4_ADDR="192.0.2.2"
-
-# How many client can connect to echo-server simultaneously
-#CONFIG_NET_SAMPLE_NUM_HANDLERS=1
diff --git a/tests/subsys/greybus/gpio/src/gpio.c b/tests/subsys/greybus/gpio/src/gpio.c
index 57b6ef2..26f2df3 100644
--- a/tests/subsys/greybus/gpio/src/gpio.c
+++ b/tests/subsys/greybus/gpio/src/gpio.c
@@ -24,6 +24,8 @@
 #include <sys/socket.h>
 #include <unistd.h>
 
+#define IPPROTO_TLS_1_2 258
+
 /* For some reason, including <net/net_ip.h> breaks everything
  * I only need these */
 static inline struct sockaddr_in *net_sin(struct sockaddr *sa)
@@ -51,6 +53,7 @@ static inline struct sockaddr_in6 *net_sin6(struct sockaddr *sa)
 LOG_MODULE_REGISTER(greybus_test_gpio, CONFIG_GREYBUS_LOG_LEVEL);
 
 /* slightly annoying */
+#include "../../../../../subsys/greybus/platform/certificate.h"
 #include "../../../../../subsys/greybus/gpio-gb.h"
 
 #include "test-greybus-gpio.h"
@@ -71,27 +74,60 @@ LOG_MODULE_REGISTER(greybus_test_gpio, CONFIG_GREYBUS_LOG_LEVEL);
 #endif
 
 static struct device *gpio_dev;
-
 static int fd = -1;
 
+#ifdef CONFIG_GREYBUS_ENABLE_TLS
+#if defined(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_OPTIONAL) \
+	|| defined(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_REQUIRED)
+#define greybus_ca NULL
+static const unsigned char greybus_client[] = {
+#include "greybus_client.inc"
+};
+static const unsigned char greybus_client_privkey[] = {
+#include "greybus_client_privkey.inc"
+};
+#else /* GREYBUS_CLIENT_VERIFY_.. */
+static const unsigned char greybus_ca[] = {
+#include "greybus_ca.inc"
+};
+#define greybus_client NULL
+#define greybus_client_privkey NULL
+#endif /* GREYBUS_CLIENT_VERIFY_.. */
+#else /* CONFIG_GREYBUS_ENABLE_TLS */
+#define greybus_ca NULL
+#define greybus_client NULL
+#define greybus_client_privkey NULL
+#endif /* CONFIG_GREYBUS_ENABLE_TLS */
+
 void test_greybus_setup(void) {
 
     struct sockaddr sa;
     socklen_t sa_len;
     int family;
     uint16_t *port;
+	int proto = IPPROTO_TCP;
     int r;
 
+	if (IS_ENABLED(CONFIG_GREYBUS_ENABLE_TLS)) {
+		proto = IPPROTO_TLS_1_2;
+	}
+
 	if (IS_ENABLED(CONFIG_NET_IPV6)) {
 		family = AF_INET6;
 		net_sin6(&sa)->sin6_family = AF_INET6;
-		inet_pton(family, MY_IPV6_ADDR, &net_sin6(&sa)->sin6_addr);
+		r = inet_pton(family, MY_IPV6_ADDR,
+			&net_sin6(&sa)->sin6_addr);
+		__ASSERT(r == 1, "%s is not a valid IPv6 address",
+			MY_IPV6_ADDR);
 		port = &net_sin6(&sa)->sin6_port;
 		sa_len = sizeof(struct sockaddr_in6);
 	} else if (IS_ENABLED(CONFIG_NET_IPV4)) {
 		family = AF_INET;
 		net_sin(&sa)->sin_family = AF_INET;
-		inet_pton(family, MY_IPV4_ADDR, &net_sin(&sa)->sin_addr);
+		r = inet_pton(family, MY_IPV4_ADDR,
+			&net_sin(&sa)->sin_addr);
+		__ASSERT(r == 1, "%s is not a valid IPv4 address",
+			MY_IPV4_ADDR);
 		port = &net_sin(&sa)->sin_port;
 		sa_len = sizeof(struct sockaddr_in);
 	} else {
@@ -103,12 +139,47 @@ void test_greybus_setup(void) {
 	gpio_dev = (struct device *)device_get_binding(GPIO_DEV_NAME);
 	zassert_not_equal(gpio_dev, NULL, "failed to get device binding for " GPIO_DEV_NAME);
 
-    r = socket(family, SOCK_STREAM, 0);
-    __ASSERT(r >= 0, "connect: %d", errno);
-    fd = r;
+	r = socket(family, SOCK_STREAM, proto);
+	__ASSERT(r >= 0, "socket: %d", errno);
+	fd = r;
+
+	if (IS_ENABLED(CONFIG_GREYBUS_ENABLE_TLS)) {
+
+		if(IS_ENABLED(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_OPTIONAL)
+			|| IS_ENABLED(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_REQUIRED)) {
+			LOG_DBG("Adding Client Certificate (Public Key) (%zu bytes)", sizeof(greybus_client));
+			r = tls_credential_add(GB_TLS_CLIENT_CERT_TAG, TLS_CREDENTIAL_SERVER_CERTIFICATE,
+					greybus_client, sizeof(greybus_client));
+			__ASSERT(r == 0, "tls_credential_add: %d", r);
+			LOG_DBG("Adding Client Certificate (Private Key) (%zu bytes)", sizeof(greybus_client_privkey));
+			r = tls_credential_add(GB_TLS_CLIENT_CERT_TAG, TLS_CREDENTIAL_PRIVATE_KEY,
+					greybus_client_privkey, sizeof(greybus_client_privkey));
+			__ASSERT(r == 0, "tls_credential_add: %d", r);
+		} else {
+			LOG_DBG("Adding CA Certificate (%zu bytes)", sizeof(greybus_client));
+			r = tls_credential_add(GB_TLS_CA_CERT_TAG, TLS_CREDENTIAL_CA_CERTIFICATE,
+					greybus_ca, sizeof(greybus_ca));
+			__ASSERT(r == 0, "tls_credential_add: %d", r);
+		}
+
+		static const sec_tag_t sec_tag_opt[] = {
+			GB_TLS_CA_CERT_TAG,
+#if defined(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_OPTIONAL) \
+	|| defined(CONFIG_GREYBUS_TLS_CLIENT_VERIFY_REQUIRED)
+			GB_TLS_CLIENT_CERT_TAG,
+#endif
+		};
+
+		r = setsockopt(fd, SOL_TLS, TLS_SEC_TAG_LIST, sec_tag_opt, sizeof(sec_tag_opt));
+		__ASSERT(r != -1, "setsockopt: Failed to set SEC_TAG_LIST (%d)", errno);
 
-    r = connect(fd, &sa, sa_len);
-    __ASSERT(r == 0, "connect: %d", errno);
+		r = setsockopt(fd, SOL_TLS, TLS_HOSTNAME, "localhost",
+			strlen("localhost"));
+		__ASSERT(r != -1, "setsockopt: Failed to set TLS_HOSTNAME (%d)", errno);
+	}
+
+	r = connect(fd, &sa, sa_len);
+	__ASSERT(r == 0, "connect: %d", errno);
 }
 
 void test_greybus_teardown(void) {
@@ -129,7 +200,7 @@ static void tx_rx(const struct gb_operation_hdr *req, struct gb_operation_hdr *r
 
     size = sys_le16_to_cpu(req->size);
     r = send(fd, req, size, 0);
-    zassert_not_equal(r, -1, "send: %s", errno);
+    zassert_not_equal(r, -1, "send: %d", errno);
     zassert_equal(r, size, "write: expected: %d actual: %d", size, r);
 
     for(;;) {
@@ -137,20 +208,17 @@ static void tx_rx(const struct gb_operation_hdr *req, struct gb_operation_hdr *r
 		pollfd.fd = fd;
 		pollfd.events = POLLIN;
 
-		LOG_DBG("calling poll on 1 file");
 		r = poll(&pollfd, 1, TIMEOUT_MS);
-		LOG_DBG("poll returned %d", r);
 		if (r == 0) {
-			LOG_DBG("poll returned 0 (timeout?)");
+			// there was a timeout... wait, really??
 			continue;
 		}
+
 		zassert_not_equal(r, -1, "poll: %s", errno);
 		//zassert_not_equal(r, 0, "timeout waiting for response");
 		zassert_equal(r, 1, "invalid number of pollfds with data: %d", r);
 
-		LOG_DBG("calling recv on fd %d", fd);
 		r = recv(fd, rsp, hdr_size, 0);
-		LOG_DBG("recv returned %d", r);
 		zassert_not_equal(r, -1, "recv: %s", errno);
 		zassert_equal(hdr_size, r, "recv: expected: %u actual: %u", (unsigned)hdr_size, r);
 
diff --git a/tests/subsys/greybus/gpio/testcase.yaml b/tests/subsys/greybus/gpio/testcase.yaml
index 882f621..466350c 100644
--- a/tests/subsys/greybus/gpio/testcase.yaml
+++ b/tests/subsys/greybus/gpio/testcase.yaml
@@ -2,3 +2,25 @@ tests:
   subsys.greybus.gpio:
     tags: greybus
     harness: ztest
+    platform_allow: mps2_an385 qemu_cortex_m3
+  subsys.greybus.gpio.tls:
+    tags: greybus tls
+    harness: ztest
+    # build_only for now due to issues in Zephyr mbedTLS / IPPROTO_TLS_1_2
+    # for details see cfriedt/greybus-for-zephyr#34
+    build_only: True
+    platform_allow: mps2_an385 qemu_x86_64
+    extra_configs:
+      - CONFIG_GREYBUS_ENABLE_TLS=y
+      - CONFIG_GREYBUS_TLS_BUILTIN=y
+      - CONFIG_NET_SOCKETS_SOCKOPT_TLS=y
+      - CONFIG_TLS_CREDENTIALS=y
+      - CONFIG_NET_PKT_RX_COUNT=64
+      - CONFIG_NET_PKT_TX_COUNT=64
+      - CONFIG_NET_BUF_RX_COUNT=64
+      - CONFIG_NET_BUF_TX_COUNT=64
+      - CONFIG_TLS_MAX_CREDENTIALS_NUMBER=5
+      - CONFIG_NET_SOCKETS_TLS_MAX_CONTEXTS=10
+      - CONFIG_ZTEST_STACKSIZE=8192
+      - CONFIG_HEAP_MEM_POOL_SIZE=32768
+      - CONFIG_PTHREAD_DYNAMIC_STACK_DEFAULT_SIZE=8192
diff --git a/zephyr-sys-byteorder-posix.patch b/zephyr-sys-byteorder-posix.patch
index 95034d1..4df2c2e 100644
--- a/zephyr-sys-byteorder-posix.patch
+++ b/zephyr-sys-byteorder-posix.patch
@@ -68,25 +68,25 @@ index fc5c56056e..7830d7dde2 100644
 +#define sys_cpu_to_le64(val) (val)
 +#define sys_be16_to_cpu(val) __builtin_bswap16(val)
 +#define sys_cpu_to_be16(val) __builtin_bswap16(val)
-+#define sys_be24_to_cpu(val) __builtin_bswap24(val)
-+#define sys_cpu_to_be24(val) __builtin_bswap24(val)
++#define sys_be24_to_cpu(val) __bswap_24(val)
++#define sys_cpu_to_be24(val) __bswap_24(val)
 +#define sys_be32_to_cpu(val) __builtin_bswap32(val)
 +#define sys_cpu_to_be32(val) __builtin_bswap32(val)
-+#define sys_be48_to_cpu(val) __builtin_bswap48(val)
-+#define sys_cpu_to_be48(val) __builtin_bswap48(val)
++#define sys_be48_to_cpu(val) __bswap_48(val)
++#define sys_cpu_to_be48(val) __bswap_48(val)
 +#define sys_be64_to_cpu(val) __builtin_bswap64(val)
 +#define sys_cpu_to_be64(val) __builtin_bswap64(val)
 +#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
-+#define sys_le16_to_cpu(val) __bswap_16(val)
-+#define sys_cpu_to_le16(val) __bswap_16(val)
++#define sys_le16_to_cpu(val) __builtin_bswap_16(val)
++#define sys_cpu_to_le16(val) __builtin_bswap_16(val)
 +#define sys_le24_to_cpu(val) __bswap_24(val)
 +#define sys_cpu_to_le24(val) __bswap_24(val)
-+#define sys_le32_to_cpu(val) __bswap_32(val)
-+#define sys_cpu_to_le32(val) __bswap_32(val)
++#define sys_le32_to_cpu(val) __builtin_bswap_32(val)
++#define sys_cpu_to_le32(val) __builtin_bswap_32(val)
 +#define sys_le48_to_cpu(val) __bswap_48(val)
 +#define sys_cpu_to_le48(val) __bswap_48(val)
-+#define sys_le64_to_cpu(val) __bswap_64(val)
-+#define sys_cpu_to_le64(val) __bswap_64(val)
++#define sys_le64_to_cpu(val) __builtin_bswap_64(val)
++#define sys_cpu_to_le64(val) __builtin_bswap_64(val)
 +#define sys_be16_to_cpu(val) (val)
 +#define sys_cpu_to_be16(val) (val)
 +#define sys_be24_to_cpu(val) (val)