Backlight: Add abstraction for support of different hardware.

firmware/common/backlight.cpp

@@ -0,0 +1,100 @@
+/*
+ * Copyright (C) 2017 Jared Boone, ShareBrained Technology, Inc.
+ *
+ * This file is part of PortaPack.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include "backlight.hpp"
+
+#include "portapack_io.hpp"
+
+namespace portapack {
+
+void BacklightOnOff::on() {
+	if( !is_on() ) {
+		io.lcd_backlight(true);
+		on_ = true;
+	}
+}
+
+void BacklightOnOff::off() {
+	if( is_on() ) {
+		io.lcd_backlight(false);
+		on_ = false;
+	}
+}
+
+void BacklightCAT4004::set_level(const value_t value) {		
+	auto target = value;
+
+	// Clip target value to valid range.
+	if( target < 0 ) {
+		target = 0;
+	}
+	if( target > maximum_level ) {
+		target = maximum_level;
+	}
+
+	if( is_on() ) {
+		pulses(target);
+	} else {
+		level_ = target;
+	}
+}
+
+void BacklightCAT4004::on() {
+	if( !is_on() ) {
+		io.lcd_backlight(true);
+		halPolledDelay(ticks_setup);
+		on_ = true;
+
+		// Just enabled driver, initial value is maximum.
+		const auto target_level = level();
+		level_ = maximum_level;
+
+		pulses(target_level);
+	}
+}
+
+void BacklightCAT4004::off() {
+	if( is_on() ) {
+		io.lcd_backlight(false);
+		chThdSleepMilliseconds(ms_pwrdwn);
+		on_ = false;
+	}
+}
+
+void BacklightCAT4004::pulses(value_t target) {
+	while(level() != target) {
+		pulse();
+	}
+}
+
+void BacklightCAT4004::pulse() {
+	io.lcd_backlight(false);
+	halPolledDelay(ticks_lo);
+	io.lcd_backlight(true);
+	halPolledDelay(ticks_hi);
+
+	level_ -= 1;
+	if( level_ < 0 ) {
+		level_ = levels() - 1;
+	}
+}
+
+} /* namespace portapack */

firmware/common/backlight.hpp

@@ -0,0 +1,120 @@
+/*
+ * Copyright (C) 2017 Jared Boone, ShareBrained Technology, Inc.
+ *
+ * This file is part of PortaPack.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#pragma once
+
+#include <cstdint>
+
+namespace portapack {
+
+class Backlight {
+public:
+	using value_t = int_fast8_t;
+
+	virtual ~Backlight() = default;
+
+	virtual value_t levels() const = 0;
+
+	virtual void set_level(const value_t value) = 0;
+	virtual value_t level() const = 0;
+
+	virtual void increase() = 0;
+	virtual void decrease() = 0;
+
+	virtual void on() = 0;
+	virtual void off() = 0;
+
+	virtual bool is_on() const = 0;
+};
+
+class BacklightBase : public Backlight {
+public:
+	void increase() override {
+		set_level(level() + 1);
+	}
+
+	void decrease() override {
+		set_level(level() - 1);
+	}
+};
+
+class BacklightOnOff : public BacklightBase {
+public:
+	value_t levels() const override {
+		return 1;
+	}
+
+	void set_level(const value_t) override {
+	}
+
+	value_t level() const override {
+		return levels() - 1;
+	}
+
+	void on() override;
+	void off() override;
+
+	bool is_on() const override {
+		return on_;
+	}
+
+private:
+	static constexpr value_t maximum_level = 1;
+
+	bool on_ { false };
+};
+
+class BacklightCAT4004 : public BacklightBase {
+public:
+	value_t levels() const override {
+		return maximum_level + 1;
+	}
+
+	void set_level(const value_t value) override;
+
+	value_t level() const override {
+		return level_;
+	}
+
+	void on() override;
+	void off() override;
+
+	bool is_on() const override {
+		return on_;
+	}
+
+private:
+	static constexpr value_t initial_brightness = 25;
+	static constexpr value_t maximum_level = 31;
+
+	static constexpr uint32_t ticks_setup  = 204e6 * 10e-6;
+	static constexpr uint32_t ms_pwrdwn    = 5;
+	static constexpr uint32_t ticks_lo     = 204e6 * 1e-6;
+	static constexpr uint32_t ticks_hi     = 204e6 * 1e-6;
+
+	value_t level_ { initial_brightness };
+	bool on_ { false };
+
+	void pulses(value_t target);
+	void pulse();
+};
+
+} /* namespace portapack */

firmware/common/lcd_ili9341.cpp

@@ -270,12 +270,9 @@ void lcd_vertical_scrolling_start_address(
 void ILI9341::init() {
 	lcd_reset();
 	lcd_init();
-
-	io.lcd_backlight(1);
 }
 
 void ILI9341::shutdown() {
-	io.lcd_backlight(0);
 	lcd_reset();
 }