Initial firmware commit.

firmware/common/i2c_pp.hpp

@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2014 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.
+ */
+
+#ifndef __I2C_PP_H__
+#define __I2C_PP_H__
+
+#include <cstdint>
+
+#include "ch.h"
+#include "hal.h"
+
+struct I2CClockConfig {
+	float clock_source_f;
+	float bus_f;
+	float high_period_ns;
+
+	constexpr I2CClockConfig(
+		float clock_source_f,
+		float bus_f,
+		float high_period_ns
+	) : clock_source_f(clock_source_f),
+		bus_f(bus_f),
+		high_period_ns(high_period_ns)
+	{
+	}
+
+	static constexpr float period_ns(const float f) {
+		return 1e9 / f;
+	}
+
+	constexpr uint32_t i2c_period_count() {
+		return period_ns(bus_f) / period_ns(clock_source_f) + 0.5f;
+	}
+
+	constexpr uint32_t i2c_high_count() {
+		return high_period_ns / period_ns(clock_source_f) + 0.5f;
+	}
+
+	constexpr uint32_t i2c_low_count() {
+		return i2c_period_count() - i2c_high_count();
+	}
+};
+
+class I2C {
+public:
+	using address_t = uint8_t;
+
+	constexpr I2C(I2CDriver* const driver) :
+		_driver(driver) {
+	}
+
+	void start(const I2CConfig& config);
+	void stop();
+
+	bool receive(
+		const address_t slave_address,
+		uint8_t* const data, const size_t count,
+		const systime_t timeout = TIME_INFINITE
+	);
+
+	bool transmit(
+		const address_t slave_address,
+		const uint8_t* const data, const size_t count,
+		const systime_t timeout = TIME_INFINITE
+	);
+
+private:
+	I2CDriver* const _driver;
+
+	bool transfer(
+		const address_t slave_address,
+		const uint8_t* const data_tx, const size_t count_tx,
+		uint8_t* const data_rx, const size_t count_rx,
+		const systime_t timeout
+	);
+};
+
+#endif/*__I2C_PP_H__*/