drivers: rename rpi_pwm_out to linux_pwm_out

src/drivers/linux_pwm_out/navio_sysfs.cpp

@@ -0,0 +1,151 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2017 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.
+ *
+ ****************************************************************************/
+
+#include "navio_sysfs.h"
+
+#include <fcntl.h>
+#include <errno.h>
+#include <px4_log.h>
+
+using namespace linux_pwm_out;
+
+NavioSysfsPWMOut::NavioSysfsPWMOut(const char *device, int max_num_outputs)
+	: _device(device)
+{
+	if (max_num_outputs > MAX_NUM_PWM) {
+		PX4_WARN("number of outputs too large. Setting to %i", MAX_NUM_PWM);
+		max_num_outputs = MAX_NUM_PWM;
+	}
+
+	for (int i = 0; i < MAX_NUM_PWM; ++i) {
+		_pwm_fd[i] = -1;
+	}
+
+	_pwm_num = max_num_outputs;
+}
+
+NavioSysfsPWMOut::~NavioSysfsPWMOut()
+{
+	for (int i = 0; i < MAX_NUM_PWM; ++i) {
+		if (_pwm_fd[i] != -1) {
+			::close(_pwm_fd[i]);
+		}
+	}
+}
+
+int NavioSysfsPWMOut::init()
+{
+	int i;
+	char path[128];
+
+	for (i = 0; i < _pwm_num; ++i) {
+		::snprintf(path, sizeof(path), "%s/export", _device);
+
+		if (pwm_write_sysfs(path, i) < 0) {
+			PX4_ERR("PWM export failed");
+		}
+	}
+
+	for (i = 0; i < _pwm_num; ++i) {
+		::snprintf(path, sizeof(path), "%s/pwm%u/enable", _device, i);
+
+		if (pwm_write_sysfs(path, 1) < 0) {
+			PX4_ERR("PWM enable failed");
+		}
+	}
+
+	for (i = 0; i < _pwm_num; ++i) {
+		::snprintf(path, sizeof(path), "%s/pwm%u/period", _device, i);
+
+		if (pwm_write_sysfs(path, (int)1e9 / FREQUENCY_PWM)) {
+			PX4_ERR("PWM period failed");
+		}
+	}
+
+	for (i = 0; i < _pwm_num; ++i) {
+		::snprintf(path, sizeof(path), "%s/pwm%u/duty_cycle", _device, i);
+		_pwm_fd[i] = ::open(path, O_WRONLY | O_CLOEXEC);
+
+		if (_pwm_fd[i] == -1) {
+			PX4_ERR("PWM: Failed to open duty_cycle.");
+			return -errno;
+		}
+	}
+
+	return 0;
+}
+
+int NavioSysfsPWMOut::send_output_pwm(const uint16_t *pwm, int num_outputs)
+{
+	char data[16];
+
+	if (num_outputs > _pwm_num) {
+		num_outputs = _pwm_num;
+	}
+
+	int ret = 0;
+
+	//convert this to duty_cycle in ns
+	for (unsigned i = 0; i < num_outputs; ++i) {
+		int n = ::snprintf(data, sizeof(data), "%u", pwm[i] * 1000);
+		int write_ret = ::write(_pwm_fd[i], data, n);
+
+		if (n != write_ret) {
+			ret = -1;
+		}
+	}
+
+	return ret;
+}
+
+int NavioSysfsPWMOut::pwm_write_sysfs(char *path, int value)
+{
+	int fd = ::open(path, O_WRONLY | O_CLOEXEC);
+	int n;
+	char data[16];
+
+	if (fd == -1) {
+		return -errno;
+	}
+
+	n = ::snprintf(data, sizeof(data), "%u", value);
+
+	if (n > 0) {
+		n = ::write(fd, data, n);	// This n is not used, but to avoid a compiler error.
+	}
+
+	::close(fd);
+
+	return 0;
+}
+