fix(build): set SPI_DEV_DIR and SPI_SPEED macros

Also improved logging.

Dockerfile

@@ -2,18 +2,20 @@
 # $OUTPUT_DIR/$SPI_BUS respectively. Also copies reset_lgw.sh
 # to $OUTPUT_DIR.
 
-FROM balenalib/raspberry-pi-debian:buster-build as sx1301-builder
+FROM balenalib/raspberry-pi-debian:buster-build as lora-gateway-sx1301-builder
 
 ENV ROOT_DIR=/opt
+
+# Output built files to this location
 ENV OUTPUT_DIR="$ROOT_DIR/output"
 
-# Overwirtes value in loragw_spi.native.c
-# https://github.com/NebraLtd/lora_gateway/blob/971c52e3e0f953102c0b057c9fff9b1df8a84d66/libloragw/src/loragw_spi.native.c#L56
+# Used in libloragw/Makefile value and supplied to loragw_spi.native.c
 ENV SPI_SPEED=2000000
 
 WORKDIR "$ROOT_DIR"
 
 # Copy upstream source into expected location
 COPY . "$ROOT_DIR"
 
+# Compile libloragw
 RUN . "$ROOT_DIR/compile_libloragw.sh"

compile_libloragw.sh

@@ -12,11 +12,11 @@ compile_libloragw_for_spi_bus() {
     cd "$ROOT_DIR"
     cp -r "$ROOT_DIR/libloragw/" "$OUTPUT_DIR/$spi_bus"
 
-    echo "Finished building libloragw for sx1301 on $spi_bus in $ROOT_DIR"
+    echo "Finished building libloragw for sx1301 on $spi_bus in $OUTPUT_DIR"
 }
 
 compile_libloragw() {
-    echo "Compiling libloragw for sx1301 concentrator on all the necessary SPI buses in $ROOT_DIR"
+    echo "Compiling libloragw for sx1301 concentrator on all the necessary SPI buses in $OUTPUT_DIR"
 
     # Built outputs will be copied to this directory
     mkdir -p "$OUTPUT_DIR"

libloragw/Makefile

@@ -10,7 +10,8 @@ CROSS_COMPILE ?=
 CC := $(CROSS_COMPILE)gcc
 AR := $(CROSS_COMPILE)ar
 
-CFLAGS := -O2 -Wall -Wextra -std=c99 -Iinc -I.
+# Modified to include SPI_DEV_PATH and SPI_SPEED macros
+CFLAGS := -O2 -Wall -Wextra -std=c99 -Iinc -I. -D'SPI_DEV_PATH="${SPI_DEV_DIR}"' -D'SPI_SPEED=${SPI_SPEED}'
 
 OBJDIR = obj
 INCLUDES = $(wildcard inc/*.h)

libloragw/src/loragw_spi.native.c

@@ -53,8 +53,9 @@ Maintainer: Sylvain Miermont
 
 #define READ_ACCESS     0x00
 #define WRITE_ACCESS    0x80
-#define SPI_SPEED       8000000
-#define SPI_DEV_PATH    "/dev/spidev0.0"
+// SPI_SPEED and SPI_DEV_PATH are intended to be defined as part of CFLAGS in the Makefile
+// #define SPI_SPEED       8000000
+// #define SPI_DEV_PATH    "/dev/spidev0.0"
 //#define SPI_DEV_PATH    "/dev/spidev32766.0"
 
 /* -------------------------------------------------------------------------- */