Backlight: Add abstraction for support of different hardware.

firmware/application/CMakeLists.txt

@@ -116,6 +116,7 @@ set(CPPSRC
 	${COMMON}/message_queue.cpp
 	${COMMON}/hackrf_hal.cpp
 	portapack.cpp
+	${COMMON}/backlight.cpp
 	${COMMON}/portapack_shared_memory.cpp
 	baseband_api.cpp
 	${COMMON}/portapack_persistent_memory.cpp

firmware/application/event_m0.cpp

@@ -123,11 +123,12 @@ void EventDispatcher::set_display_sleep(const bool sleep) {
 	// TODO: Distribute display sleep message more broadly, shut down data generation
 	// on baseband side, since all that data is being discarded during sleep.
 	if( sleep ) {
-		portapack::io.lcd_backlight(false);
+		portapack::backlight()->off();
 		portapack::display.sleep();
 	} else {
 		portapack::display.wake();
-		portapack::io.lcd_backlight(true);
+		// Don't turn on backlight here.
+		// Let frame sync handler turn on backlight after repaint.
 	}
 	display_sleep = sleep;
 };
@@ -268,6 +269,8 @@ void EventDispatcher::handle_lcd_frame_sync() {
 	DisplayFrameSyncMessage message;
 	message_map.send(&message);
 	painter.paint_widget_tree(top_widget);
+
+	portapack::backlight()->on();
 }
 
 void EventDispatcher::handle_switches() {

firmware/application/portapack.cpp

@@ -31,6 +31,7 @@ using namespace hackrf::one;
 
 #include "clock_manager.hpp"
 
+#include "backlight.hpp"
 #include "touch_adc.hpp"
 #include "audio.hpp"
 
@@ -56,6 +57,9 @@ portapack::IO io {
 	portapack::gpio_unused,
 };
 
+portapack::BacklightCAT4004 backlight_cat4004;
+portapack::BacklightOnOff   backlight_on_off;
+
 lcd::ILI9341 display;
 
 I2C i2c0(&I2CD0);
@@ -147,6 +151,12 @@ static const portapack::cpld::Config& portapack_cpld_config() {
 		;
 }
 
+Backlight* backlight() {
+	return (portapack_model() == PortaPackModel::R2_20170522)
+		? static_cast<portapack::Backlight*>(&backlight_cat4004)
+		: static_cast<portapack::Backlight*>(&backlight_on_off);
+}
+
 static void shutdown_base() {
 	clock_manager.shutdown();
 
@@ -272,6 +282,7 @@ bool init() {
 void shutdown() {
 	gpdma::controller.disable();
 
+	backlight()->off();
 	display.shutdown();
 	
 	radio::disable();

firmware/application/portapack.hpp

@@ -29,6 +29,7 @@
 #include "spi_pp.hpp"
 #include "si5351.hpp"
 #include "lcd_ili9341.hpp"
+#include "backlight.hpp"
 
 #include "radio.hpp"
 #include "clock_manager.hpp"
@@ -53,4 +54,6 @@ extern TemperatureLogger temperature_logger;
 bool init();
 void shutdown();
 
+Backlight* backlight();
+
 } /* namespace portapack */