System76 common board directory (#53)

* Move configuration for battery into board.mk

* lemp9: remove tcpm code

* Move touchpad to its own module

* Add kbled_reset to all platforms, move items to run on CPU reset to a function

* Add defines for battery and charger address

* Add I2C_0 export to it5570e

* Move common system76 board functions into src/board/system76/common

src/board/system76/common/scratch/scratch.mk

@@ -0,0 +1,53 @@
+# Set scratch ROM parameters
+SCRATCH_OFFSET=1024
+SCRATCH_SIZE=1024
+CFLAGS+=-DSCRATCH_OFFSET=$(SCRATCH_OFFSET) -DSCRATCH_SIZE=$(SCRATCH_SIZE)
+
+# Copy parameters to use when compiling scratch ROM
+SCRATCH_INCLUDE=$(INCLUDE)
+SCRATCH_CFLAGS=$(CFLAGS)
+
+#Include scratch source
+SCRATCH_DIR=$(SYSTEM76_COMMON_DIR)/scratch
+SCRATCH_SRC=$(wildcard $(SCRATCH_DIR)/*.c)
+SCRATCH_INCLUDE+=$(wildcard $(SCRATCH_DIR)/include/scratch/*.h) $(SCRATCH_DIR)/scratch.mk
+SCRATCH_CFLAGS+=-I$(SCRATCH_DIR)/include -D__SCRATCH__
+
+# Add minimal source from other directories
+SCRATCH_SRC+=\
+	$(COMMON_DIR)/version.c \
+	$(SYSTEM76_COMMON_DIR)/smfi.c
+
+SCRATCH_BUILD=$(BUILD)/scratch
+SCRATCH_OBJ=$(patsubst src/%.c,$(SCRATCH_BUILD)/%.rel,$(SCRATCH_SRC))
+SCRATCH_CC=\
+	sdcc \
+	-mmcs51 \
+	--model-small \
+	--code-loc $(SCRATCH_OFFSET) \
+	--code-size $(SCRATCH_SIZE) \
+	--Werror
+
+# Convert from binary file to C header
+$(BUILD)/include/scratch.h: $(SCRATCH_BUILD)/scratch.rom
+	@mkdir -p $(@D)
+	xxd -s $(SCRATCH_OFFSET) --include < $< > $@
+
+# Convert from Intel Hex file to binary file
+$(SCRATCH_BUILD)/scratch.rom: $(SCRATCH_BUILD)/scratch.ihx
+	@mkdir -p $(@D)
+	makebin -p < $< > $@
+
+# Link object files into Intel Hex file
+$(SCRATCH_BUILD)/scratch.ihx: $(SCRATCH_OBJ)
+	@mkdir -p $(@D)
+	$(SCRATCH_CC) -o $@ $^
+
+# Compile C files into object files
+$(SCRATCH_OBJ): $(SCRATCH_BUILD)/%.rel: src/%.c $(SCRATCH_INCLUDE)
+	@mkdir -p $(@D)
+	$(SCRATCH_CC) $(SCRATCH_CFLAGS) -o $@ -c $<
+
+# Include scratch header in main firmware
+CFLAGS+=-I$(BUILD)/include
+INCLUDE+=$(BUILD)/include/scratch.h