drivers: modem: gsm_ppp: Use DTS

Convert the gsm_ppp driver to use DTS.

Signed-off-by: Yong Cong Sin <yongcong.sin@gmail.com>

drivers/modem/Kconfig.gsm

@@ -29,9 +29,6 @@ config MODEM_GSM_SIMCOM
 
 endchoice
 
-config MODEM_GSM_UART_NAME
-	string "UART device name the modem is connected to"
-
 config MODEM_GSM_RX_STACK_SIZE
 	int "Size of the stack allocated for receiving data from modem"
 	default 512

drivers/modem/gsm_ppp.c

@@ -4,6 +4,8 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+#define DT_DRV_COMPAT zephyr_gsm_ppp
+
 #include <logging/log.h>
 LOG_MODULE_REGISTER(modem_gsm, CONFIG_MODEM_LOG_LEVEL);
 
@@ -24,6 +26,7 @@ LOG_MODULE_REGISTER(modem_gsm, CONFIG_MODEM_LOG_LEVEL);
 
 #include <stdio.h>
 
+#define GSM_UART_NODE                   DT_INST_BUS(0)
 #define GSM_CMD_READ_BUF                128
 #define GSM_CMD_AT_TIMEOUT              K_SECONDS(2)
 #define GSM_CMD_SETUP_TIMEOUT           K_SECONDS(6)
@@ -522,8 +525,7 @@ static struct net_if *ppp_net_if(void)
 static void set_ppp_carrier_on(struct gsm_modem *gsm)
 {
 	static const struct ppp_api *api;
-	const struct device *ppp_dev =
+	const struct device *ppp_dev = DEVICE_DT_GET(DT_INST(0, zephyr_gsm_ppp));
-		device_get_binding(CONFIG_NET_PPP_DRV_NAME);
 	struct net_if *iface = gsm->iface;
 	int ret;
 
@@ -821,7 +823,7 @@ static void mux_setup(struct k_work *work)
 {
 	struct gsm_modem *gsm = CONTAINER_OF(work, struct gsm_modem,
 					     gsm_configure_work);
-	const struct device *uart = device_get_binding(CONFIG_MODEM_GSM_UART_NAME);
+	const struct device *uart = DEVICE_DT_GET(GSM_UART_NODE);
 	int ret;
 
 	/* We need to call this to reactivate mux ISR. Note: This is only called
@@ -980,7 +982,7 @@ void gsm_ppp_start(const struct device *dev)
 
 	/* Re-init underlying UART comms */
 	int r = modem_iface_uart_init_dev(&gsm->context.iface,
-				device_get_binding(CONFIG_MODEM_GSM_UART_NAME));
+				DEVICE_DT_GET(GSM_UART_NODE));
 	if (r) {
 		LOG_ERR("modem_iface_uart_init returned %d", r);
 		return;
@@ -1057,7 +1059,7 @@ static int gsm_init(const struct device *dev)
 	gsm->gsm_data.rx_rb_buf_len = sizeof(gsm->gsm_rx_rb_buf);
 
 	r = modem_iface_uart_init(&gsm->context.iface, &gsm->gsm_data,
-				device_get_binding(CONFIG_MODEM_GSM_UART_NAME));
+				DEVICE_DT_GET(GSM_UART_NODE));
 	if (r < 0) {
 		LOG_DBG("iface uart error %d", r);
 		return r;
@@ -1091,5 +1093,5 @@ static int gsm_init(const struct device *dev)
 	return 0;
 }
 
-DEVICE_DEFINE(gsm_ppp, GSM_MODEM_DEVICE_NAME, gsm_init, NULL, &gsm, NULL,
+DEVICE_DT_DEFINE(DT_INST(0, zephyr_gsm_ppp), gsm_init, NULL, &gsm, NULL,
-	      POST_KERNEL, CONFIG_MODEM_GSM_INIT_PRIORITY, NULL);
+		 POST_KERNEL, CONFIG_MODEM_GSM_INIT_PRIORITY, NULL);

drivers/net/ppp.c

@@ -862,7 +862,7 @@ static int ppp_start(const struct device *dev)
 
 		dev_name = mux->name;
 #elif IS_ENABLED(CONFIG_MODEM_GSM_PPP)
-		dev_name = CONFIG_MODEM_GSM_UART_NAME;
+		dev_name = DT_BUS_LABEL(DT_INST(0, zephyr_gsm_ppp));
 #else
 		dev_name = CONFIG_NET_PPP_UART_NAME;
 #endif

dts/bindings/modem/zephyr,gsm-ppp.yaml

@@ -0,0 +1,8 @@
+# Copyright (c) 2021 G-Technologies Sdn. Bhd.
+# SPDX-License-Identifier: Apache-2.0
+
+description: GSM PPP modem
+
+compatible: "zephyr,gsm-ppp"
+
+include: uart-device.yaml

include/drivers/gsm_ppp.h

@@ -7,8 +7,6 @@
 #ifndef GSM_PPP_H_
 #define GSM_PPP_H_
 
-#define GSM_MODEM_DEVICE_NAME "modem_gsm"
-
 /** @cond INTERNAL_HIDDEN */
 struct device;
 void gsm_ppp_start(const struct device *dev);

samples/net/cloud/tagoio_http_post/README.rst

@@ -87,17 +87,27 @@ Modem
 The Modem support is quite similar to WIFI, you need a board with an embedded
 Modem support or you can add a shield.  Currently, the overlay was created to
 allow modems with PPP support.  This was tested using ``SIMcom SIM808 EVB``.
-Additionally you need fill ``CONFIG_MODEM_GSM_UART_NAME`` with the UART label
+Additionally you need fill ``CONFIG_MODEM_GSM_APN`` with the correspondent Access
-``CONFIG_MODEM_GSM_APN`` with the correspondent Access Point Name (APN) at
+Point Name (APN) at
-:zephyr_file:`samples/net/cloud/tagoio_http_post/overlay-modem.conf` file.
+:zephyr_file:`samples/net/cloud/tagoio_http_post/overlay-modem.conf` file. A
+DTC overlay file should be used to configure the glue between the modem and the
+uart port. It can reside at boards directory, with the board name, or it can be
+a special designator like defined at ``arduino.overlay``.
 
 .. zephyr-app-commands::
    :zephyr-app: samples/net/cloud/tagoio_http_post
-   :board: [sam4e_xpro | frdm_k64f]
+   :board: sam4e_xpro
    :gen-args: -DOVERLAY_CONFIG=overlay-modem.conf
    :goals: build flash
    :compact:
 
+.. zephyr-app-commands::
+   :zephyr-app: samples/net/cloud/tagoio_http_post
+   :board: frdm_k64f
+   :gen-args: -DOVERLAY_CONFIG=overlay-modem.conf -DDTC_OVERLAY_FILE=arduino.overlay
+   :goals: build flash
+   :compact:
+
 In a terminal window you can check if communication is happen:
 
 .. code-block:: console

samples/net/cloud/tagoio_http_post/arduino.overlay

@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2021 G-Technologies Sdn. Bhd.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+ &arduino_serial {
+	status = "okay";
+	current-speed = <115200>;
+
+	gsm: gsm-modem {
+		compatible = "zephyr,gsm-ppp";
+		label = "gsm_ppp";
+	};
+};

samples/net/cloud/tagoio_http_post/boards/sam4e_xpro.overlay

@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2021 G-Technologies Sdn. Bhd.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+&usart1 {
+	status = "okay";
+	current-speed = <115200>;
+
+	gsm: gsm-modem {
+		compatible = "zephyr,gsm-ppp";
+		label = "gsm_ppp";
+	};
+};

samples/net/cloud/tagoio_http_post/overlay-modem.conf

@@ -7,7 +7,6 @@ CONFIG_MODEM_SHELL=y
 CONFIG_MODEM_CMD_HANDLER_MAX_PARAM_COUNT=20
 CONFIG_MODEM_GSM_PPP=y
 CONFIG_MODEM_GSM_RX_STACK_SIZE=1024
-CONFIG_MODEM_GSM_UART_NAME="<your board UART port label>"
 CONFIG_MODEM_GSM_APN="<your Access Point Name (APN)>"
 
 # Network management events

samples/net/cloud/tagoio_http_post/sample.yaml

@@ -16,4 +16,7 @@ tests:
     platform_allow: frdm_k64f nucleo_f767zi
   sample.net.cloud.tagoio_http_post.modem:
     extra_args: OVERLAY_CONFIG="overlay-modem.conf"
-    platform_allow: sam4e_xpro frdm_k64f
+    platform_allow: sam4e_xpro
+  sample.net.cloud.tagoio_http_post.modem.arduino:
+    extra_args: OVERLAY_CONFIG="overlay-modem.conf" DTC_OVERLAY_FILE="arduino.overlay"
+    platform_allow: frdm_k64f

samples/net/gsm_modem/boards/frdm_uart2_dts.overlay

@@ -6,4 +6,8 @@
 &uart2 {
 	status = "okay";
 	current-speed = <115200>;
+	gsm: gsm-modem {
+		compatible = "zephyr,gsm-ppp";
+		label = "gsm_ppp";
+	};
 };

samples/net/gsm_modem/prj.conf

@@ -4,7 +4,6 @@ CONFIG_SERIAL=y
 # GSM modem support
 CONFIG_MODEM=y
 CONFIG_MODEM_GSM_PPP=y
-CONFIG_MODEM_GSM_UART_NAME="UART_1"
 
 # PPP networking support
 CONFIG_NET_PPP=y

samples/net/gsm_modem/sample.yaml

@@ -2,6 +2,8 @@ common:
   harness: net
   depends_on: serial-net
   tags: net ppp modem gsm
+  platform_allow: frdm_k64f
+  extra_args: DTC_OVERLAY_FILE="boards/frdm_uart2_dts.overlay"
 sample:
   description: Sample for generic GSM modem
   name: Generic GSM modem using PPP

samples/net/gsm_modem/src/main.c

@@ -93,13 +93,14 @@ static void event_handler(struct net_mgmt_event_callback *cb,
 int main(void)
 {
 	const struct device *uart_dev =
-				device_get_binding(CONFIG_MODEM_GSM_UART_NAME);
+		DEVICE_DT_GET(DT_BUS(DT_INST(0, zephyr_gsm_ppp)));
 
-	gsm_dev = device_get_binding(GSM_MODEM_DEVICE_NAME);
+	gsm_dev = DEVICE_DT_GET(DT_INST(0, zephyr_gsm_ppp));
 
 	LOG_INF("Board '%s' APN '%s' UART '%s' device %p (%s)",
 		CONFIG_BOARD, CONFIG_MODEM_GSM_APN,
-		CONFIG_MODEM_GSM_UART_NAME, uart_dev, GSM_MODEM_DEVICE_NAME);
+		DT_BUS_LABEL(DT_INST(0, zephyr_gsm_ppp)), uart_dev,
+		gsm_dev->name);
 
 	net_mgmt_init_event_callback(&mgmt_cb, event_handler,
 				     NET_EVENT_L4_CONNECTED |

samples/subsys/mgmt/updatehub/arduino.overlay

@@ -6,7 +6,9 @@
 
 &arduino_serial {
 	status = "okay";
-	label = "arduino_serial";
-
 	current-speed = <115200>;
+	gsm: gsm-modem {
+		compatible = "zephyr,gsm-ppp";
+		label = "gsm_ppp";
+	};
 };

samples/subsys/mgmt/updatehub/overlay-modem.conf

@@ -15,7 +15,6 @@ CONFIG_SERIAL=y
 CONFIG_MODEM=y
 CONFIG_MODEM_SHELL=y
 CONFIG_MODEM_GSM_PPP=y
-CONFIG_MODEM_GSM_UART_NAME="arduino_serial"
 CONFIG_MODEM_GSM_APN="<Your Access Point Network>"
 
 # PPP networking support

samples/subsys/mgmt/updatehub/src/main.c

@@ -139,10 +139,10 @@ void main(void)
 
 #elif defined(CONFIG_MODEM_GSM_PPP)
 	const struct device *uart_dev =
-		device_get_binding(CONFIG_MODEM_GSM_UART_NAME);
+		DEVICE_DT_GET(DT_BUS(DT_INST(0, zephyr_gsm_ppp)));
 
 	LOG_INF("APN '%s' UART '%s' device %p", CONFIG_MODEM_GSM_APN,
-		CONFIG_MODEM_GSM_UART_NAME, uart_dev);
+		DT_BUS_LABEL(DT_INST(0, zephyr_gsm_ppp)), uart_dev);
 #endif
 
 	net_mgmt_init_event_callback(&mgmt_cb, event_handler, EVENT_MASK);

tests/drivers/build_all/modem/modem.conf

@@ -15,4 +15,3 @@ CONFIG_MODEM_HL7800_APN_NAME="internet"
 CONFIG_MODEM_HL7800_RAT_M1=y
 CONFIG_MODEM_WNCM14A2A=y
 CONFIG_MODEM_GSM_PPP=y
-CONFIG_MODEM_GSM_UART_NAME="TEST_UART_CTLR"

tests/drivers/build_all/modem/uart.dtsi

@@ -45,3 +45,8 @@ test_quectel_bg9x: quectel_bg9x {
 	mdm-power-gpios = <&test_gpio 0 0>;
 	mdm-reset-gpios = <&test_gpio 0 0>;
 };
+
+test_gsm_ppp: gsm_ppp {
+	compatible = "zephyr,gsm-ppp";
+	label = "gsm_ppp";
+};