i2c+spi: add module base class and bus iterators

2026-10-24 03:53:33 +08:00 · 2020-03-10 10:11:43 -04:00
parent af15c7d945
commit 06712450a7
10 changed files with 1151 additions and 2 deletions
@@ -0,0 +1,100 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2020 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#pragma once
+
+#include <board_config.h>
+
+#define I2C_BUS_MAX_BUS_ITEMS PX4_NUMBER_I2C_BUSES
+
+struct px4_i2c_bus_t {
+	int bus{-1}; ///< physical bus number (1, ...) (-1 means this is unused)
+	bool is_external; ///< static external configuration. Use px4_i2c_bus_external() to check if a bus is really external
+};
+
+__EXPORT extern const px4_i2c_bus_t px4_i2c_buses[I2C_BUS_MAX_BUS_ITEMS]; ///< board-specific I2C bus configuration
+
+/**
+ * runtime-check if a board has a specific bus as external.
+ * This can be overridden by a board to add run-time checks.
+ */
+__EXPORT bool px4_i2c_bus_external(const px4_i2c_bus_t &bus);
+
+/**
+ * runtime-check if a board has a specific bus as external.
+ */
+static inline bool px4_i2c_bus_external(int bus)
+{
+	for (int i = 0; i < I2C_BUS_MAX_BUS_ITEMS; ++i) {
+		if (px4_i2c_buses[i].bus == bus) {
+			return px4_i2c_bus_external(px4_i2c_buses[i]);
+		}
+	}
+
+	return true;
+}
+
+
+/**
+ * @class I2CBusIterator
+ * Iterate over configured I2C buses by the board
+ */
+class I2CBusIterator
+{
+public:
+	enum class FilterType {
+		All, ///< specific or all buses
+		InternalBus, ///< specific or all internal buses
+		ExternalBus, ///< specific or all external buses
+	};
+
+	/**
+	 * @param bus specify bus: starts with 1, -1=all. Internal: arch-specific bus numbering is used,
+	 *             external: n-th external bus
+	 */
+	I2CBusIterator(FilterType filter, int bus = -1)
+		: _filter(filter), _bus(bus) {}
+
+	bool next();
+
+	const px4_i2c_bus_t &bus() const { return px4_i2c_buses[_index]; }
+
+	bool external() const { return px4_i2c_bus_external(bus()); }
+
+private:
+	const FilterType _filter;
+	const int _bus;
+	int _index{-1};
+	int _external_bus_counter{0};
+};
+