Some makefile cleanup to genericise things a bit and start to support linux and osx

Makefile

@@ -1,32 +1,71 @@
-# Arduino Make file. Refer to https://github.com/sudar/Arduino-Makefile
 
-#BOARD_TAG    = keyboardio
-BOARD    = model01
-MCU 		= atmega32u4
+# Shamelessly stolen from git's Makefile
+uname_S := $(shell sh -c 'uname -s 2>/dev/null || echo not')
+
+
+DEVICE_PORT := `ls /dev/ttyACM*`
+DEVICE_PORT_BOOTLOADER := `ls /dev/ttyACM*`
+ARDUINO_PATH=/usr/local/arduino
+ARDUINO_LOCAL_LIB_PATH=$(HOME)/Arduino
+
+
+ifeq ($(uname_S),Darwin)
+
+# Port locations
 
 DEVICE_PORT :=  `ls /dev/cu.usbmodemHID?? /dev/cu.usbmodem14*`
 DEVICE_PORT_BOOTLOADER := `ls /dev/cu.usbmodem14*`
-ARDUINO_LIBS = 
-GIT_VERSION := $(shell git describe --abbrev=4 --dirty --always)
+
+# Tools
 
 ARDUINO_PATH=/Applications/Arduino.app/Contents/Java/
+ARDUINO_LOCAL_LIB_PATH=$(HOME)/Documents/Arduino
+
+endif
+
+
+
 ARDUINO_TOOLS_PATH=$(ARDUINO_PATH)/hardware/tools
+ARDUINO_BUILDER_PATH=$(ARDUINO_PATH)/arduino-builder
+AVRDUDE_PATH=$(ARDUINO_TOOLS_PATH)/avr/bin/avrdude
+AVRDUDE_CONF_PATH=$(ARDUINO_TOOLS_PATH)/avr/etc/avrdude.conf
+AVR_SIZE_PATH=$(ARDUINO_TOOLS_PATH)/avr/bin/avr-size
+
+
+
+#
+#
+# Device and sketch info
+#
+#
+
+BOARD    = model01
+MCU 		= atmega32u4
 FQBN=keyboardio:avr:model01
+SKETCH=KeyboardioFirmware.ino
+BOOTLOADER_PATH = $(ARDUINO_LOCAL_LIB_PATH)/hardware/keyboardio/avr/bootloaders/caterina/Caterina.hex
+VERBOSE= #-verbose
+
+#
+#
+# Build
+#
+#
+
 BUILD_PATH := $(shell mktemp -d 2>/dev/null || mktemp -d -t 'build')
 OUTPUT_PATH=./output
-ARDUINO_LOCAL_LIB_PATH=$(HOME)/Documents/Arduino
 ARDUINO_IDE_VERSION=100607
-VERBOSE= #-verbose
-SKETCH=KeyboardioFirmware.ino
-
-AVR_SIZE=$(ARDUINO_TOOLS_PATH)/avr/bin/avr-size
 
+#
+#
+# Output 
+#
+#
 
+GIT_VERSION := $(shell git describe --abbrev=4 --dirty --always)
 OUTPUT_FILE_PREFIX=$(SKETCH)-$(GIT_VERSION)
-
 HEX_FILE_PATH=$(OUTPUT_PATH)/$(OUTPUT_FILE_PREFIX).hex
 ELF_FILE_PATH=$(OUTPUT_PATH)/$(OUTPUT_FILE_PREFIX).elf
-
 HEX_FILE_WITH_BOOTLOADER_PATH=$(OUTPUT_PATH)/$(OUTPUT_FILE_PREFIX)-with-bootloader.hex
 
 # default action for `make` is `build`
@@ -45,7 +84,7 @@ dirs:
 	mkdir -p $(OUTPUT_PATH)
 
 compile: dirs
-	$(ARDUINO_PATH)/arduino-builder \
+	$(ARDUINO_BUILDER_PATH) \
 		-hardware $(ARDUINO_PATH)/hardware \
 		-hardware $(ARDUINO_LOCAL_LIB_PATH)/hardware \
 		-tools $(ARDUINO_TOOLS_PATH) \
@@ -63,14 +102,14 @@ compile: dirs
 	@echo "Have fun!\n"
 
 size: compile
-	$(AVR_SIZE) -C --mcu=$(MCU) $(ELF_FILE_PATH)
+	$(AVR_SIZE_PATH) -C --mcu=$(MCU) $(ELF_FILE_PATH)
 
 
 hex-with-bootloader: compile
 	@cat $(HEX_FILE_PATH) | awk '/^:00000001FF/ == 0' > $(HEX_FILE_WITH_BOOTLOADER_PATH)
-	@echo "Using $(ARDUINO_LOCAL_LIB_PATH)/hardware/keyboardio/avr/bootloaders/caterina/Caterina.hex"
-	@md5 $(ARDUINO_LOCAL_LIB_PATH)/hardware/keyboardio/avr/bootloaders/caterina/Caterina.hex
-	@cat $(ARDUINO_LOCAL_LIB_PATH)/hardware/keyboardio/avr/bootloaders/caterina/Caterina.hex >> $(HEX_FILE_WITH_BOOTLOADER_PATH)
+	@echo "Using $(BOOTLOADER_PATH)"
+	@md5 $(BOOTLOADER_PATH)
+	@cat $(BOOTLOADER_PATH) >> $(HEX_FILE_WITH_BOOTLOADER_PATH)
 	@echo "Combined firmware and bootloader are now at $(HEX_FILE_WITH_BOOTLOADER_PATH)"
 	@echo "Make sure you have the bootloader version you expect."
 	@echo "\n\nAnd TEST THIS ON REAL HARDWARE BEFORE YOU GIVE IT TO ANYONE\n\n"
@@ -80,8 +119,8 @@ reset-device:
 
 flash: compile reset-device
 	sleep 3
-	$(ARDUINO_TOOLS_PATH)/avr/bin/avrdude \
-		-C$(ARDUINO_TOOLS_PATH)/avr/etc/avrdude.conf \
+	$(AVRDUDE_PATH) \
+		-C$(AVRDUDE_CONF_PATH) \
 		-v \
 		-p$(MCU) \
 		-cavr109 \
@@ -91,8 +130,8 @@ flash: compile reset-device
 		-Uflash:w:$(HEX_FILE_PATH):i 
 
 program:
-	$(ARDUINO_TOOLS_PATH)/avr/bin/avrdude \
-		-C$(ARDUINO_TOOLS_PATH)/avr/etc/avrdude.conf \
+	$(AVRDUDE_PATH) \
+		-C$(AVRDUDE_CONF_PATH) \
 		-v \
 		-p$(MCU) \
 		-cusbtiny \