qmi: add NetworkMonitor interface

This is a rudimentary implementation that contains technology and RSSI
and BitErrorRate, plus RSRQ/RSRP for LTE networks.  More data can be
added as needed.

This implementations uses the 'Get Signal Strength' QMI method to retrieve
the data.  Operator fields (MNC, LAC, etc) can be gotten from the 'Serving
Cell' method if needed, but since this data is already provided in the
NetworkRegistration object it doesn't seem necessary to repeat it here
when an additional communication to the modem is required.

Makefile.am

@@ -233,7 +233,8 @@ builtin_sources += $(qmi_sources) \
 			drivers/qmimodem/gprs.c \
 			drivers/qmimodem/gprs-context.c \
 			drivers/qmimodem/radio-settings.c \
-			drivers/qmimodem/location-reporting.c
+			drivers/qmimodem/location-reporting.c \
+			drivers/qmimodem/netmon.c
 
 builtin_modules += gobi
 builtin_sources += plugins/gobi.c

drivers/qmimodem/netmon.c

@@ -0,0 +1,286 @@
+/*
+ *
+ *  oFono - Open Source Telephony
+ *
+ *  Copyright (C) 2017  Jonas Bonn. All rights reserved.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <errno.h>
+
+#include <glib.h>
+
+#include <ofono/log.h>
+#include <ofono/modem.h>
+#include <ofono/netmon.h>
+
+#include "qmi.h"
+#include "nas.h"
+
+#include "qmimodem.h"
+#include "src/common.h"
+
+struct netmon_data {
+	struct qmi_service *nas;
+};
+
+static void get_rssi_cb(struct qmi_result *result, void *user_data)
+{
+	struct cb_data *cbd = user_data;
+	struct ofono_netmon *netmon = cbd->user;
+	ofono_netmon_cb_t cb = cbd->cb;
+	struct {
+		enum ofono_netmon_cell_type type;
+		int rssi;
+		int ber;
+		int rsrq;
+		int rsrp;
+	} props;
+	uint16_t len;
+	int16_t rsrp;
+	const struct {
+		int8_t value;
+		int8_t rat;
+	} __attribute__((__packed__)) *rsrq;
+	const struct {
+		uint16_t count;
+		struct {
+			uint8_t rssi;
+			int8_t rat;
+		} __attribute__((__packed__)) info[0];
+	} __attribute__((__packed__)) *rssi;
+	const struct {
+		uint16_t count;
+		struct {
+			uint16_t rate;
+			int8_t rat;
+		} __attribute__((__packed__)) info[0];
+	} __attribute__((__packed__)) *ber;
+	int i;
+	uint16_t num;
+
+	DBG("");
+
+	if (qmi_result_set_error(result, NULL)) {
+		CALLBACK_WITH_FAILURE(cb, cbd->data);
+		return;
+	}
+
+	/* RSSI */
+	rssi = qmi_result_get(result, 0x11, &len);
+	num = GUINT16_FROM_LE(rssi->count);
+	if (rssi) {
+		for (i = 0; i < num; i++) {
+			DBG("RSSI: %hhu on RAT %hhd",
+				rssi->info[i].rssi,
+				rssi->info[i].rat);
+		}
+
+		/* Get cell type from RSSI info... it will be the same
+		 * for all the other entries
+		 */
+		props.type = qmi_nas_rat_to_tech(rssi->info[0].rat);
+		switch (rssi->info[0].rat) {
+		case QMI_NAS_NETWORK_RAT_GSM:
+			props.type = OFONO_NETMON_CELL_TYPE_GSM;
+			break;
+		case QMI_NAS_NETWORK_RAT_UMTS:
+			props.type = OFONO_NETMON_CELL_TYPE_UMTS;
+			break;
+		case QMI_NAS_NETWORK_RAT_LTE:
+			props.type = OFONO_NETMON_CELL_TYPE_LTE;
+			break;
+		default:
+			props.type = OFONO_NETMON_CELL_TYPE_GSM;
+			break;
+		}
+
+		props.rssi = (rssi->info[0].rssi + 113) / 2;
+		if (props.rssi > 31) props.rssi = 31;
+		if (props.rssi < 0) props.rssi = 0;
+	} else {
+		props.type = QMI_NAS_NETWORK_RAT_GSM;
+		props.rssi = -1;
+	}
+
+	/* Bit error rate */
+	ber = qmi_result_get(result, 0x15, &len);
+	num = GUINT16_FROM_LE(ber->count);
+	if (ber) {
+		for (i = 0; i < ber->count; i++) {
+			DBG("Bit error rate: %hu on RAT %hhd",
+				GUINT16_FROM_LE(ber->info[i].rate),
+				ber->info[i].rat);
+		}
+
+		props.ber = GUINT16_FROM_LE(ber->info[0].rate);
+		if (props.ber > 7)
+			props.ber = -1;
+	} else {
+		props.ber = -1;
+	}
+
+	/* LTE RSRQ */
+	rsrq = qmi_result_get(result, 0x16, &len);
+	if (rsrq) {
+		DBG("RSRQ: %hhd on RAT %hhd",
+			rsrq->value,
+			rsrq->rat);
+
+		if (rsrq->value == 0) {
+			props.rsrq = -1;
+		} else {
+			props.rsrq = (rsrq->value + 19) * 2;
+			if (props.rsrq > 34) props.rsrq = 34;
+			if (props.rsrq < 0) props.rsrq = 0;
+		}
+	} else {
+		props.rsrq = -1;
+	}
+
+	/* LTE RSRP */
+	if (qmi_result_get_int16(result, 0x18, &rsrp)) {
+		DBG("Got LTE RSRP: %hd", rsrp);
+
+		if (rsrp == 0) {
+			props.rsrp = -1;
+		} else {
+			props.rsrp = rsrp + 140;
+			if (props.rsrp > 97) props.rsrp = 97;
+			if (props.rsrp < 0) props.rsrp = 0;
+		}
+	} else {
+		props.rsrp = -1;
+	}
+
+	ofono_netmon_serving_cell_notify(netmon,
+				props.type,
+				OFONO_NETMON_INFO_RSSI, props.rssi,
+				OFONO_NETMON_INFO_BER, props.ber,
+				OFONO_NETMON_INFO_RSRQ, props.rsrq,
+				OFONO_NETMON_INFO_RSRP, props.rsrp,
+				OFONO_NETMON_INFO_INVALID);
+
+	CALLBACK_WITH_SUCCESS(cb, cbd->data);
+}
+
+static void qmi_netmon_request_update(struct ofono_netmon *netmon,
+					ofono_netmon_cb_t cb,
+					void *user_data)
+{
+	struct netmon_data *data = ofono_netmon_get_data(netmon);
+	struct cb_data *cbd = cb_data_new(cb, user_data);
+	struct qmi_param *param;
+
+	DBG("");
+
+	cbd->user = netmon;
+
+	param = qmi_param_new();
+	if (!param)
+		goto out;
+
+	/* Request all signal strength items: mask=0xff */
+	qmi_param_append_uint16(param, 0x10, 255);
+
+	if (qmi_service_send(data->nas, QMI_NAS_GET_RSSI, param,
+					get_rssi_cb, cbd, g_free) > 0)
+		return;
+
+	qmi_param_free(param);
+
+out:
+	CALLBACK_WITH_FAILURE(cb, cbd->data);
+
+	g_free(cbd);
+}
+
+static void create_nas_cb(struct qmi_service *service, void *user_data)
+{
+	struct ofono_netmon *netmon = user_data;
+	struct netmon_data *nmd = ofono_netmon_get_data(netmon);
+
+	DBG("");
+
+	if (!service) {
+		ofono_error("Failed to request NAS service");
+		ofono_netmon_remove(netmon);
+		return;
+	}
+
+	nmd->nas = qmi_service_ref(service);
+
+	ofono_netmon_register(netmon);
+}
+
+static int qmi_netmon_probe(struct ofono_netmon *netmon,
+					unsigned int vendor, void *user_data)
+{
+	struct qmi_device *device = user_data;
+	struct netmon_data *nmd;
+
+	DBG("");
+
+	nmd = g_new0(struct netmon_data, 1);
+
+	ofono_netmon_set_data(netmon, nmd);
+
+	qmi_service_create_shared(device, QMI_SERVICE_NAS,
+					create_nas_cb, netmon, NULL);
+
+	return 0;
+}
+
+static void qmi_netmon_remove(struct ofono_netmon *netmon)
+{
+	struct netmon_data *nmd = ofono_netmon_get_data(netmon);
+
+	DBG("");
+
+	ofono_netmon_set_data(netmon, NULL);
+
+	qmi_service_unregister_all(nmd->nas);
+
+	qmi_service_unref(nmd->nas);
+
+	g_free(nmd);
+}
+
+static struct ofono_netmon_driver driver = {
+	.name			= "qmimodem",
+	.probe			= qmi_netmon_probe,
+	.remove			= qmi_netmon_remove,
+	.request_update		= qmi_netmon_request_update,
+};
+
+void qmi_netmon_init(void)
+{
+	ofono_netmon_driver_register(&driver);
+}
+
+void qmi_netmon_exit(void)
+{
+	ofono_netmon_driver_unregister(&driver);
+}

drivers/qmimodem/qmimodem.c

@@ -41,12 +41,14 @@ static int qmimodem_init(void)
 	qmi_gprs_context_init();
 	qmi_radio_settings_init();
 	qmi_location_reporting_init();
+	qmi_netmon_init();
 
 	return 0;
 }
 
 static void qmimodem_exit(void)
 {
+	qmi_netmon_exit();
 	qmi_location_reporting_exit();
 	qmi_radio_settings_exit();
 	qmi_gprs_context_exit();

drivers/qmimodem/qmimodem.h

@@ -53,3 +53,6 @@ extern void qmi_radio_settings_exit(void);
 
 extern void qmi_location_reporting_init(void);
 extern void qmi_location_reporting_exit(void);
+
+extern void qmi_netmon_init(void);
+extern void qmi_netmon_exit(void);