drivers: modem: Added SMS subsystem for modem

drivers/modem/Kconfig

@@ -1,6 +1,7 @@
 # Modem configuration options
 
 # Copyright (c) 2018 Foundries.io
+# Copyright (c) 2023 T-Mobile USA, Inc.
 # SPDX-License-Identifier: Apache-2.0
 
 menuconfig MODEM
@@ -192,6 +193,7 @@ source "drivers/modem/Kconfig.ublox-sara-r4"
 source "drivers/modem/Kconfig.quectel-bg9x"
 source "drivers/modem/Kconfig.wncm14a2a"
 source "drivers/modem/Kconfig.gsm"
+source "drivers/modem/Kconfig.sms"
 
 source "drivers/modem/Kconfig.hl7800"
 source "drivers/modem/Kconfig.simcom-sim7080"

drivers/modem/Kconfig.sms

@@ -0,0 +1,43 @@
+# Modem SMS options
+
+# Copyright (c) 2023 T-Moblie
+# SPDX-License-Identifier: Apache-2.0
+
+menuconfig MODEM_SMS
+		bool "Modem SMS handler"
+		default y
+		depends on MODEM_CONTEXT
+		help
+		  Choose this setting to enable SMS functionality for
+		  modems.
+
+if MODEM_SMS
+
+config MODEM_SMS_IN_MSG_MAX_LEN
+		int "Maximum length of inbound SMS messages"
+		default 160
+		help
+		  This is the maximum length of inbound (received) SMS messages.
+		  Inbound SMS messages longer than this will be truncated.
+		  The absolute maximum value may be network- and/or modem-dependent,
+		  but a smaller value may be preferred in order to conserve memory.
+
+config MODEM_SMS_OUT_MSG_MAX_LEN
+		int "Maximum length of outbound SMS messages"
+		default MODEM_SMS_IN_MSG_MAX_LEN
+		help
+		  This is the maximum length of outbound SMS messages (being sent).
+		  SMS message send requests longer than this are not possible.
+		  The absolute maximum value may be network- and/or modem-dependent,
+		  but a smaller value may be preferred in order to conserve memory.
+
+config MODEM_SMS_CALLBACK
+		bool "Use SMS Receive callbacks"
+		default n
+		help
+			This option allows a callback to be registered for SMS receive
+			events. SMS messages reported via the callback will not be
+			buffered, and therefore client code must handle buffering if
+			required.
+
+endif # MODEM_SMS

drivers/modem/modem_context.h

@@ -7,6 +7,7 @@
 
 /*
  * Copyright (c) 2019 Foundries.io
+ * Copyright (c) 2023 T-Mobile USA, Inc.
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -20,6 +21,8 @@
 #include <zephyr/sys/ring_buffer.h>
 #include <zephyr/drivers/gpio.h>
 
+#include <zephyr/drivers/modem/sms.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -68,6 +71,16 @@ struct modem_context {
 	/* command handler config */
 	struct modem_cmd_handler cmd_handler;
 
+	/* modem device pointer */
+	const struct device *dev;
+
+#if defined(CONFIG_MODEM_SMS)
+	/* SMS functions */
+	send_sms_func_t send_sms;
+	recv_sms_func_t recv_sms;
+	recv_sms_cb_en_func_t recv_sms_cb_en;
+#endif
+
 	/* driver data */
 	void *driver_data;
 };

drivers/modem/modem_sms.c

@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2023 T-Mobile USA, Inc.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/kernel.h>
+#include <zephyr/drivers/modem/sms.h>
+
+#include "modem_sms.h"
+#include "modem_context.h"
+
+static sys_slist_t sms_recv_cbs = SYS_SLIST_STATIC_INIT(&sms_recv_cbs);
+
+void notify_sms_recv(const struct device *dev, struct sms_in *sms, int csms_ref, int csms_idx,
+			 int csms_tot)
+{
+	struct sms_recv_cb *cb, *next;
+
+	SYS_SLIST_FOR_EACH_CONTAINER_SAFE(&sms_recv_cbs, cb, next, node) {
+		if (cb->recv) {
+			cb->recv(dev, sms, csms_ref, csms_idx, csms_tot);
+		}
+	}
+}
+
+static struct modem_context *modem_context_from_modem_dev(const struct device *dev)
+{
+	struct modem_context *mctx;
+
+	for (int i = 0; i < CONFIG_MODEM_CONTEXT_MAX_NUM; i++) {
+		mctx = modem_context_from_id(i);
+		if (mctx && mctx->dev == dev) {
+			return mctx;
+		}
+	}
+	return 0;
+}
+
+int sms_msg_send(const struct device *dev, const struct sms_out *sms)
+{
+	struct modem_context *mctx;
+
+	mctx = modem_context_from_modem_dev(dev);
+
+	if (!mctx) {
+		return -ENODEV;
+	}
+
+	if (!mctx->send_sms) {
+		return -ENOSYS;
+	}
+
+	return mctx->send_sms(sms);
+}
+
+int sms_msg_recv(const struct device *dev, struct sms_in *sms)
+{
+	struct modem_context *mctx;
+
+	mctx = modem_context_from_modem_dev(dev);
+
+	if (!mctx) {
+		return -ENODEV;
+	}
+
+	if (!mctx->recv_sms) {
+		return -ENOSYS;
+	}
+
+	return mctx->recv_sms(sms);
+}
+
+#if defined(CONFIG_MODEM_SMS_CALLBACK)
+
+int sms_recv_cb_en(const struct device *dev, bool enable)
+{
+	struct modem_context *mctx;
+
+	mctx = modem_context_from_modem_dev(dev);
+
+	if (!mctx) {
+		return -ENODEV;
+	}
+
+	if (!mctx->recv_sms_cb_en) {
+		return -ENOSYS;
+	}
+
+	return mctx->recv_sms_cb_en(enable);
+}
+
+int sms_recv_cb_register(struct sms_recv_cb *cb)
+{
+	if (cb == NULL) {
+		return -EINVAL;
+	}
+
+	sys_slist_append(&sms_recv_cbs, &cb->node);
+
+	return 0;
+}
+
+int sms_recv_cb_unregister(struct sms_recv_cb *cb)
+{
+	if (cb == NULL) {
+		return -EINVAL;
+	}
+
+	if (!sys_slist_find_and_remove(&sms_recv_cbs, &cb->node)) {
+		return -EALREADY;
+	}
+
+	return 0;
+}
+
+#endif /* CONFIG_MODEM_SMS_CALLBACK */

drivers/modem/modem_sms.h

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2023 T-Mobile USA, Inc.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_DRIVERS_MODEM_MODEM_SMS_H_
+#define ZEPHYR_DRIVERS_MODEM_MODEM_SMS_H_
+
+#include <zephyr/drivers/modem/sms.h>
+
+/**
+ * @brief Notify all registered callbacks of a received SMS message
+ *
+ * @param dev Device pointer of modem which received the SMS message
+ * @param sms Received SMS message
+ * @param csms_ref CSMS Reference number (if available, value is set to -1 if not)
+ * @param csms_idx CSMS Index number (if available, value is set to 0 if not)
+ * @param csms_tot CSMS Total segment count (if available, value is set to 1 if not)
+ *
+ */
+void notify_sms_recv(const struct device *dev, struct sms_in *sms, int csms_ref, int csms_idx,
+		       int csms_tot);
+
+#endif /* ZEPHYR_DRIVERS_MODEM_MODEM_SMS_H_ */