mpu9250: start building "NuttX" driver for Linux and QuRT

2026-10-25 22:53:33 +08:00 · 2019-11-13 09:21:02 -05:00
parent 6bd4273b9c
commit c5520cbaca
36 changed files with 1159 additions and 869 deletions
@@ -0,0 +1,118 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2012-2015 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.
+ *
+ ****************************************************************************/
+
+/**
+ * @file i2c.cpp
+ *
+ * Base class for devices attached via the I2C bus.
+ *
+ * @todo Bus frequency changes; currently we do nothing with the value
+ *       that is supplied.  Should we just depend on the bus knowing?
+ */
+
+#include "I2C.hpp"
+
+#include "dev_fs_lib_i2c.h"
+
+namespace device
+{
+
+I2C::I2C(const char *name, const char *devname, const int bus, const uint16_t address, const uint32_t frequency) :
+	CDev(name, devname)
+{
+	DEVICE_DEBUG("I2C::I2C name = %s devname = %s", name, devname);
+	// fill in _device_id fields for a I2C device
+	_device_id.devid_s.bus_type = DeviceBusType_I2C;
+	_device_id.devid_s.bus = bus;
+	_device_id.devid_s.address = address;
+	// devtype needs to be filled in by the driver
+	_device_id.devid_s.devtype = 0;
+}
+
+I2C::~I2C()
+{
+	if (_fd >= 0) {
+		::close(_fd);
+		_fd = -1;
+	}
+}
+
+int
+I2C::init()
+{
+	// Assume the driver set the desired bus frequency. There is no standard
+	// way to set it from user space.
+
+	// do base class init, which will create device node, etc
+	int ret = CDev::init();
+
+	if (ret != PX4_OK) {
+		DEVICE_DEBUG("CDev::init failed");
+		return ret;
+	}
+
+	// Open the actual I2C device
+	char dev_path[16];
+	snprintf(dev_path, sizeof(dev_path), "/dev/iic-%i", get_device_bus());
+	_fd = ::open(dev_path, O_RDWR);
+
+	if (_fd < 0) {
+		PX4_ERR("could not open %s", dev_path);
+		px4_errno = errno;
+		return PX4_ERROR;
+	}
+
+	return ret;
+}
+
+int
+I2C::transfer(const uint8_t *send, const unsigned send_len, uint8_t *recv, const unsigned recv_len)
+{
+	dspal_i2c_ioctl_combined_write_read ioctl_write_read{};
+
+	ioctl_write_read.write_buf = (uint8_t *)send;
+	ioctl_write_read.write_buf_len = send_len;
+	ioctl_write_read.read_buf = recv;
+	ioctl_write_read.read_buf_len = recv_len;
+
+	int bytes_read = ::ioctl(_fd, I2C_IOCTL_RDWR, &ioctl_write_read);
+
+	if (bytes_read != (ssize_t)recv_len) {
+		PX4_ERR("read register reports a read of %d bytes, but attempted to read %d bytes", bytes_read, recv_len);
+		return -1;
+	}
+
+	return 0;
+}
+
+} // namespace device