Restore GNSS ingestion for lat, lon, and elev telemetry.

Re-add the ModemManager sidecar and gnss_reader integration so GPS data
from the EG25 modem is merged into CSV, InfluxDB, and radio outputs.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: sunpi

Makefile

@@ -1,27 +1,28 @@
-CC      ?= cc
-CFLAGS  ?= -std=c11 -O2 -Wall -Wextra -Wpedantic
-CFLAGS  += -Isrc -Ithird_party
-
-SRC = \
-    src/main.c \
-    src/config.c \
-    src/influx.c \
-    src/format_loader.c \
-    src/can_reader.c \
-    src/decoder.c \
-    src/encoder.c \
-    src/db_watcher.c \
-    src/writer.c \
-    src/serial_radio.c \
-    third_party/cJSON.c
-
-TARGET = can_telem
-LDFLAGS ?= -lcurl -lsqlite3 -lpthread -lm
-
-$(TARGET): $(SRC)
-	$(CC) $(CFLAGS) $(SRC) -o $@ $(LDFLAGS)
-
-clean:
-	rm -f $(TARGET)
-
-.PHONY: clean
+CC      ?= cc
+CFLAGS  ?= -std=c11 -O2 -Wall -Wextra -Wpedantic
+CFLAGS  += -Isrc -Ithird_party
+
+SRC = \
+    src/main.c \
+    src/config.c \
+    src/influx.c \
+    src/format_loader.c \
+    src/can_reader.c \
+    src/decoder.c \
+    src/encoder.c \
+    src/db_watcher.c \
+    src/writer.c \
+    src/serial_radio.c \
+    src/gnss_reader.c \
+    third_party/cJSON.c
+
+TARGET = can_telem
+LDFLAGS ?= -lcurl -lsqlite3 -lpthread -lm
+
+$(TARGET): $(SRC)
+	$(CC) $(CFLAGS) $(SRC) -o $@ $(LDFLAGS)
+
+clean:
+	rm -f $(TARGET)
+
+.PHONY: clean

README.md

@@ -300,6 +300,7 @@ can-telem-cloud/
 │   ├── writer.[ch]       — CSV append sink
 │   ├── influx.[ch]       — InfluxDB Cloud batch upload sink
 │   ├── serial_radio.[ch] — UART radio sink (RFD900A / CP2102)
+│   ├── gnss_reader.[ch]  — GNSS cache reader (lat/lon/elev injection)
 │   ├── encoder.[ch]      — CAN signal encoder (for TX path)
 │   └── db_watcher.[ch]   — SQLite DB watcher for TX signals
 ├── third_party/

can_telem.conf.example

@@ -18,11 +18,11 @@ can_interface = can0
 # influx_token = paste-token-here
 # Or omit influx_token and run: export INFLUX_TOKEN=...
 # influx_upload_interval_ms = 1000
-# Production mobile app contract:
-#   telemetry_snapshot,signal=<name> value=<number>
-# Keep this unset to use the default telemetry_snapshot measurement, or set it
-# explicitly for clarity.
-# influx_measurement = telemetry_snapshot
+# Production mobile app contract:
+#   telemetry_snapshot,signal=<name> value=<number>
+# Keep this unset to use the default telemetry_snapshot measurement, or set it
+# explicitly for clarity.
+# influx_measurement = telemetry_snapshot
 
 # --- Optional: DB-driven CAN transmit (SQLite) ---
 # Enable this to poll values from a SQLite DB and transmit updates on CAN for
@@ -46,3 +46,17 @@ can_interface = can0
 # radio_device = /dev/ttyUSB0
 # radio_baud = 9600
 # radio_flush_interval_ms = 1000
+
+# --- Optional: signal role filters (without editing sc-data-format) ---
+# Comma-separated signal names. Leave empty/missing to allow all.
+# rx_signals = pack_voltage,pack_current,soc,lat,lon,elev
+# tx_signals = torque_cmd,drive_mode
+
+# --- Optional: GNSS merge ---
+# Pull lat/lon/elev from /run/can_telem/gnss.json (written by gnss_service.py)
+# gnss_enabled = true
+# gnss_poll_interval_ms = 1000
+# gnss_cache_path = /run/can_telem/gnss.json
+# gnss_lat_signal = lat
+# gnss_lon_signal = lon
+# gnss_elev_signal = elev

deploy/can-telem-gnss.service

@@ -0,0 +1,15 @@
+[Unit]
+Description=can-telem GNSS cache service
+After=network-online.target ModemManager.service
+Wants=network-online.target
+
+[Service]
+Type=simple
+ExecStart=/usr/bin/python3 /home/sunpi/can-telem-cloud/tools/gnss_service.py
+Restart=always
+RestartSec=2
+User=root
+Group=root
+
+[Install]
+WantedBy=multi-user.target

src/can_reader.c

@@ -15,7 +15,57 @@
 
 #include "decoder.h"
 
-#define PLACEHOLDER_CAN_ID 0xFFFu
+static int rx_allowed(const config_file_t *cf, const char *sig_name) {
+    if (!cf || !cf->has_rx_signals || cf->rx_signals[0] == '\0') return 1;
+    return config_list_contains(cf->rx_signals, sig_name);
+}
+
+static const signal_def_t *find_signal_by_name(const signal_table_t *table, const char *name) {
+    if (!table || !name || !name[0]) return NULL;
+    for (size_t b = 0; b < SIG_TABLE_BUCKETS; ++b) {
+        for (const sig_node_t *n = table->buckets[b]; n; n = n->next) {
+            if (strcmp(n->sig.name, name) == 0) return &n->sig;
+        }
+    }
+    return NULL;
+}
+
+static void inject_one_signal(writer_t *w,
+                              influx_ctx_t *influx,
+                              serial_radio_ctx_t *radio,
+                              const config_file_t *cf,
+                              const signal_def_t *sig,
+                              double value) {
+    if (!sig || !rx_allowed(cf, sig->name)) return;
+    decoded_value_t dv;
+    memset(&dv, 0, sizeof dv);
+    dv.value = value;
+    strcpy(dv.raw_hex, "gnss");
+    writer_append(w, sig, &dv);
+    if (influx) influx_accumulate(influx, sig, &dv);
+    serial_radio_accumulate(radio, sig, &dv);
+}
+
+static void maybe_inject_gnss(const signal_table_t *table,
+                              writer_t *w,
+                              influx_ctx_t *influx,
+                              serial_radio_ctx_t *radio,
+                              gnss_reader_t *gnss,
+                              const config_file_t *cf,
+                              const signal_def_t *lat_sig,
+                              const signal_def_t *lon_sig,
+                              const signal_def_t *elev_sig) {
+    (void)table;
+    if (!gnss || !gnss->enabled) return;
+    (void)gnss_reader_tick(gnss);
+
+    double lat = 0.0, lon = 0.0, elev = 0.0;
+    if (!gnss_reader_get_fix(gnss, &lat, &lon, &elev)) return;
+
+    inject_one_signal(w, influx, radio, cf, lat_sig, lat);
+    inject_one_signal(w, influx, radio, cf, lon_sig, lon);
+    inject_one_signal(w, influx, radio, cf, elev_sig, elev);
+}
 
 int can_reader_open(const char *ifname) {
     if (!ifname) return -1;
@@ -45,7 +95,6 @@ int can_reader_open(const char *ifname) {
         close(s);
         return -1;
     }
-
     return s;
 }
 
@@ -54,9 +103,21 @@ int can_reader_loop(int fd,
                     writer_t *w,
                     influx_ctx_t *influx,
                     serial_radio_ctx_t *radio,
+                    gnss_reader_t *gnss,
+                    const config_file_t *cf,
                     volatile sig_atomic_t *running) {
     if (fd < 0 || !table || !w || !running) return -1;
 
+    const char *lat_name = (cf && cf->has_gnss_lat_signal && cf->gnss_lat_signal[0])
+        ? cf->gnss_lat_signal : "lat";
+    const char *lon_name = (cf && cf->has_gnss_lon_signal && cf->gnss_lon_signal[0])
+        ? cf->gnss_lon_signal : "lon";
+    const char *elev_name = (cf && cf->has_gnss_elev_signal && cf->gnss_elev_signal[0])
+        ? cf->gnss_elev_signal : "elev";
+    const signal_def_t *lat_sig = find_signal_by_name(table, lat_name);
+    const signal_def_t *lon_sig = find_signal_by_name(table, lon_name);
+    const signal_def_t *elev_sig = find_signal_by_name(table, elev_name);
+
     struct can_frame frame;
     while (*running) {
         int poll_ms = 200;
@@ -68,6 +129,7 @@ int can_reader_loop(int fd,
             return -1;
         }
         if (pr == 0) {
+            maybe_inject_gnss(table, w, influx, radio, gnss, cf, lat_sig, lon_sig, elev_sig);
             writer_tick(w);
             if (influx) influx_tick(influx);
             serial_radio_tick(radio);
@@ -96,6 +158,7 @@ int can_reader_loop(int fd,
         for (; node; node = node->next) {
             if (node->sig.can_id != id) continue;
             if (node->sig.placeholder) continue;
+            if (!rx_allowed(cf, node->sig.name)) continue;
 
             decoded_value_t dv;
             if (decoder_extract(&node->sig, frame.data,
@@ -106,10 +169,11 @@ int can_reader_loop(int fd,
             if (influx) influx_accumulate(influx, &node->sig, &dv);
             serial_radio_accumulate(radio, &node->sig, &dv);
         }
+
+        maybe_inject_gnss(table, w, influx, radio, gnss, cf, lat_sig, lon_sig, elev_sig);
         writer_tick(w);
         if (influx) influx_tick(influx);
         serial_radio_tick(radio);
     }
-
     return 0;
 }

src/can_reader.h

@@ -1,36 +1,26 @@
-#ifndef CAN_TELEM_CAN_READER_H
-#define CAN_TELEM_CAN_READER_H
-
-#include <signal.h>
-#include <stdbool.h>
-#include <stdint.h>
-
-#include "format_loader.h"
-#include "influx.h"
-#include "serial_radio.h"
-#include "writer.h"
-
-/*
- * Open a raw SocketCAN socket bound to `ifname`.
- * Returns a file descriptor >= 0 on success, or -1 on error.
- */
-int can_reader_open(const char *ifname);
-
-/*
- * Blocking receive loop: reads frames from `fd`, matches each ID against
- * `table`, decodes every matching signal (skipping placeholders with
- * can_id==0xFFF) and appends the value via the writer.
- * If `influx` is non-NULL and enabled, updates Influx aggregators and may
- * flush to the cloud on a timer.
- * If `radio` is non-NULL and enabled, accumulates the latest value per
- * signal and flushes them to the serial radio on a separate timer.
- * Runs until `*running` becomes 0.
- */
-int can_reader_loop(int fd,
-                    const signal_table_t *table,
-                    writer_t *w,
-                    influx_ctx_t *influx,
-                    serial_radio_ctx_t *radio,
-                    volatile sig_atomic_t *running);
-
-#endif
+#ifndef CAN_TELEM_CAN_READER_H
+#define CAN_TELEM_CAN_READER_H
+
+#include <signal.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "config.h"
+#include "format_loader.h"
+#include "gnss_reader.h"
+#include "influx.h"
+#include "serial_radio.h"
+#include "writer.h"
+
+int can_reader_open(const char *ifname);
+
+int can_reader_loop(int fd,
+                    const signal_table_t *table,
+                    writer_t *w,
+                    influx_ctx_t *influx,
+                    serial_radio_ctx_t *radio,
+                    gnss_reader_t *gnss,
+                    const config_file_t *cf,
+                    volatile sig_atomic_t *running);
+
+#endif