PX4-Autopilot/src/drivers/linux_pwm_out/linux_pwm_out.cpp

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#include "linux_pwm_out.hpp"

#include <board_pwm_out.h>
#include <drivers/drv_hrt.h>

using namespace pwm_out;

LinuxPWMOut::LinuxPWMOut() :
	CDev("/dev/pwm_out"),
	OutputModuleInterface(MODULE_NAME, px4::wq_configurations::hp_default),
	_cycle_perf(perf_alloc(PC_ELAPSED, MODULE_NAME": cycle")),
	_interval_perf(perf_alloc(PC_INTERVAL, MODULE_NAME": interval"))
{
	_mixing_output.setAllMinValues(PWM_DEFAULT_MIN);
	_mixing_output.setAllMaxValues(PWM_DEFAULT_MAX);
}

LinuxPWMOut::~LinuxPWMOut()
{
	/* clean up the alternate device node */
	unregister_class_devname(PWM_OUTPUT_BASE_DEVICE_PATH, _class_instance);

	perf_free(_cycle_perf);
	perf_free(_interval_perf);
	delete _pwm_out;
}

int LinuxPWMOut::init()
{
	/* do regular cdev init */
	int ret = CDev::init();

	if (ret != OK) {
		return ret;
	}

	/* try to claim the generic PWM output device node as well - it's OK if we fail at this */
	_class_instance = register_class_devname(PWM_OUTPUT_BASE_DEVICE_PATH);

	_mixing_output.setDriverInstance(_class_instance);

	_pwm_out = new BOARD_PWM_OUT_IMPL(MAX_ACTUATORS);

	ret = _pwm_out->init();

	if (ret != 0) {
		PX4_ERR("PWM output init failed");
		delete _pwm_out;
		_pwm_out = nullptr;
		return ret;
	}

	update_params();

	ScheduleNow();

	return ret;
}

int LinuxPWMOut::task_spawn(int argc, char *argv[])
{
	LinuxPWMOut *instance = new LinuxPWMOut();

	if (instance) {
		_object.store(instance);
		_task_id = task_id_is_work_queue;

		if (instance->init() == PX4_OK) {
			return PX4_OK;
		}

	} else {
		PX4_ERR("alloc failed");
	}

	delete instance;
	_object.store(nullptr);
	_task_id = -1;

	return PX4_ERROR;
}

bool LinuxPWMOut::updateOutputs(bool stop_motors, uint16_t outputs[MAX_ACTUATORS],
				unsigned num_outputs, unsigned num_control_groups_updated)
{
	_pwm_out->send_output_pwm(outputs, num_outputs);
	return true;
}

void LinuxPWMOut::Run()
{
	if (should_exit()) {
		ScheduleClear();
		_mixing_output.unregister();

		exit_and_cleanup();
		return;
	}

	perf_begin(_cycle_perf);
	perf_count(_interval_perf);

	_mixing_output.update();

	// check for parameter updates
	if (_parameter_update_sub.updated()) {
		// clear update
		parameter_update_s pupdate;
		_parameter_update_sub.copy(&pupdate);

		// update parameters from storage
		update_params();
	}

	_mixing_output.updateSubscriptions(false);

	perf_end(_cycle_perf);
}

void LinuxPWMOut::update_params()
{
	updateParams();

	// skip update when armed
	if (_mixing_output.armed().armed) {
		return;
	}

	int32_t pwm_min_default = PWM_DEFAULT_MIN;
	int32_t pwm_max_default = PWM_DEFAULT_MAX;
	int32_t pwm_disarmed_default = 0;

	const char *prefix;

	if (_class_instance == CLASS_DEVICE_PRIMARY) {
		prefix = "PWM_MAIN";

		param_get(param_find("PWM_MAIN_MIN"), &pwm_min_default);
		param_get(param_find("PWM_MAIN_MAX"), &pwm_max_default);
		param_get(param_find("PWM_MAIN_DISARM"), &pwm_disarmed_default);

	} else if (_class_instance == CLASS_DEVICE_SECONDARY) {
		prefix = "PWM_AUX";

		param_get(param_find("PWM_AUX_MIN"), &pwm_min_default);
		param_get(param_find("PWM_AUX_MAX"), &pwm_max_default);
		param_get(param_find("PWM_AUX_DISARM"), &pwm_disarmed_default);

	} else if (_class_instance == CLASS_DEVICE_TERTIARY) {
		prefix = "PWM_EXTRA";

		param_get(param_find("PWM_EXTRA_MIN"), &pwm_min_default);
		param_get(param_find("PWM_EXTRA_MAX"), &pwm_max_default);
		param_get(param_find("PWM_EXTRA_DISARM"), &pwm_disarmed_default);

	} else {
		PX4_ERR("invalid class instance %d", _class_instance);
		return;
	}

	char str[17];

	for (unsigned i = 0; i < MAX_ACTUATORS; i++) {
		// PWM_MAIN_MINx
		{
			sprintf(str, "%s_MIN%u", prefix, i + 1);
			int32_t pwm_min = -1;

			if (param_get(param_find(str), &pwm_min) == PX4_OK && pwm_min >= 0) {
				_mixing_output.minValue(i) = math::constrain(pwm_min, PWM_LOWEST_MIN, PWM_HIGHEST_MIN);

				if (pwm_min != _mixing_output.minValue(i)) {
					int32_t pwm_min_new = _mixing_output.minValue(i);
					param_set(param_find(str), &pwm_min_new);
				}

			} else {
				_mixing_output.minValue(i) = pwm_min_default;
			}
		}

		// PWM_MAIN_MAXx
		{
			sprintf(str, "%s_MAX%u", prefix, i + 1);
			int32_t pwm_max = -1;

			if (param_get(param_find(str), &pwm_max) == PX4_OK && pwm_max >= 0) {
				_mixing_output.maxValue(i) = math::constrain(pwm_max, PWM_LOWEST_MAX, PWM_HIGHEST_MAX);

				if (pwm_max != _mixing_output.maxValue(i)) {
					int32_t pwm_max_new = _mixing_output.maxValue(i);
					param_set(param_find(str), &pwm_max_new);
				}

			} else {
				_mixing_output.maxValue(i) = pwm_max_default;
			}
		}

		// PWM_MAIN_FAILx
		{
			sprintf(str, "%s_FAIL%u", prefix, i + 1);
			int32_t pwm_failsafe = -1;

			if (param_get(param_find(str), &pwm_failsafe) == PX4_OK && pwm_failsafe >= 0) {
				_mixing_output.failsafeValue(i) = math::constrain(pwm_failsafe, 0, PWM_HIGHEST_MAX);

				if (pwm_failsafe != _mixing_output.failsafeValue(i)) {
					int32_t pwm_fail_new = _mixing_output.failsafeValue(i);
					param_set(param_find(str), &pwm_fail_new);
				}
			}
		}

		// PWM_MAIN_DISx
		{
			sprintf(str, "%s_DIS%u", prefix, i + 1);
			int32_t pwm_dis = -1;

			if (param_get(param_find(str), &pwm_dis) == PX4_OK && pwm_dis >= 0) {
				_mixing_output.disarmedValue(i) = math::constrain(pwm_dis, 0, PWM_HIGHEST_MAX);

				if (pwm_dis != _mixing_output.disarmedValue(i)) {
					int32_t pwm_dis_new = _mixing_output.disarmedValue(i);
					param_set(param_find(str), &pwm_dis_new);
				}

			} else {
				_mixing_output.disarmedValue(i) = pwm_disarmed_default;
			}
		}

		// PWM_MAIN_REVx
		{
			sprintf(str, "%s_REV%u", prefix, i + 1);
			int32_t pwm_rev = 0;

			if (param_get(param_find(str), &pwm_rev) == PX4_OK) {
				uint16_t &reverse_pwm_mask = _mixing_output.reverseOutputMask();

				if (pwm_rev >= 1) {
					reverse_pwm_mask = reverse_pwm_mask | (2 << i);

				} else {
					reverse_pwm_mask = reverse_pwm_mask & ~(2 << i);
				}
			}
		}
	}

	if (_mixing_output.mixers()) {
		int16_t values[MAX_ACTUATORS] {};

		for (unsigned i = 0; i < MAX_ACTUATORS; i++) {
			sprintf(str, "%s_TRIM%u", prefix, i + 1);

			float pval = 0.0f;
			param_get(param_find(str), &pval);
			values[i] = roundf(10000 * pval);
		}

		// copy the trim values to the mixer offsets
		_mixing_output.mixers()->set_trims(values, MAX_ACTUATORS);
	}
}

int LinuxPWMOut::ioctl(device::file_t *filp, int cmd, unsigned long arg)
{
	int ret = OK;

	PX4_DEBUG("ioctl cmd: %d, arg: %ld", cmd, arg);

	lock();

	switch (cmd) {
	case MIXERIOCRESET:
		_mixing_output.resetMixerThreadSafe();
		break;

	case MIXERIOCLOADBUF: {
			const char *buf = (const char *)arg;
			unsigned buflen = strlen(buf);
			ret = _mixing_output.loadMixerThreadSafe(buf, buflen);
			update_params();
			break;
		}

	default:
		ret = -ENOTTY;
		break;
	}

	unlock();

	if (ret == -ENOTTY) {
		ret = CDev::ioctl(filp, cmd, arg);
	}

	return ret;
}

int LinuxPWMOut::custom_command(int argc, char *argv[])
{
	return print_usage("unknown command");
}

int LinuxPWMOut::print_status()
{
	perf_print_counter(_cycle_perf);
	perf_print_counter(_interval_perf);
	_mixing_output.printStatus();
	return 0;
}

int LinuxPWMOut::print_usage(const char *reason)
{
	if (reason) {
		PX4_WARN("%s\n", reason);
	}

	PRINT_MODULE_DESCRIPTION(
		R"DESCR_STR(
### Description
Linux PWM output driver with board-specific backend implementation.
)DESCR_STR");

	PRINT_MODULE_USAGE_NAME("linux_pwm_out", "driver");
	PRINT_MODULE_USAGE_COMMAND("start");
	PRINT_MODULE_USAGE_DEFAULT_COMMANDS();

	return 0;
}

extern "C" __EXPORT int linux_pwm_out_main(int argc, char *argv[])
{
	return LinuxPWMOut::main(argc, argv);
}