Make more features optional

Preparatory work to introduce a second SoC : 2nd series 3/4

Some modules won't be used on other designs, make them optional.

Signed-off-by: Vincent Palatin <vpalatin@chromium.org>

BUG=None
TEST=run the EC firmware on BDS and check that the commands from the
optional features are still available and working.

Change-Id: I979864ed94dc4da90c1010bd2e4589d84bc2d046

2 files changed, 13 insertions, 3 deletions

diff --git a/chip/lm4/build.mk b/chip/lm4/build.mk
index b69b2d7d9a..cfd78e9866 100644
--- a/chip/lm4/build.mk
+++ b/chip/lm4/build.mk
@@ -8,7 +8,11 @@
 # LM4 SoC has a Cortex-M4 ARM core
 CORE:=cortex-m
 
-chip-y=pwm.o i2c.o adc.o jtag.o
-chip-y+=clock.o gpio.o system.o lpc.o uart.o power_button.o
-chip-y+=flash.o watchdog.o eeprom.o temp_sensor.o hwtimer.o
+chip-y=i2c.o adc.o jtag.o
+chip-y+=clock.o gpio.o system.o uart.o power_button.o
+chip-y+=watchdog.o eeprom.o hwtimer.o
+chip-$(CONFIG_FLASH)+=flash.o
+chip-$(CONFIG_LPC)+=lpc.o
+chip-$(CONFIG_PWM)+=pwm.o
+chip-$(CONFIG_TEMP_SENSOR)+=temp_sensor.o
 chip-$(CONFIG_TASK_KEYSCAN)+=keyboard_scan.o
diff --git a/chip/lm4/config.h b/chip/lm4/config.h
index d4f81d253c..4ae55d185f 100644
--- a/chip/lm4/config.h
+++ b/chip/lm4/config.h
@@ -31,5 +31,11 @@
 /* build with assertions and debug messages */
 #define CONFIG_DEBUG
 
+/* Optional features */
+#define CONFIG_FLASH
+#define CONFIG_LPC
+#define CONFIG_PWM
+#define CONFIG_TEMP_SENSOR
+
 /* Compile for running from RAM instead of flash */
 /* #define COMPILE_FOR_RAM */