Moved all drivers to new world, PX4IO completely in new world

src/modules/px4iofirmware/mixer.cpp

@@ -0,0 +1,311 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 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 mixer.cpp
+ *
+ * Control channel input/output mixer and failsafe.
+ */
+
+#include <nuttx/config.h>
+#include <syslog.h>
+
+#include <sys/types.h>
+#include <stdbool.h>
+#include <string.h>
+
+#include <drivers/drv_pwm_output.h>
+#include <drivers/drv_hrt.h>
+
+#include <systemlib/mixer/mixer.h>
+
+extern "C" {
+//#define DEBUG
+#include "px4io.h"
+}
+
+/*
+ * Maximum interval in us before FMU signal is considered lost
+ */
+#define FMU_INPUT_DROP_LIMIT_US		200000
+
+/* XXX need to move the RC_CHANNEL_FUNCTION out of rc_channels.h and into systemlib */
+#define ROLL     0
+#define PITCH    1
+#define YAW      2
+#define THROTTLE 3
+#define OVERRIDE 4
+
+/* current servo arm/disarm state */
+static bool mixer_servos_armed = false;
+
+/* selected control values and count for mixing */
+enum mixer_source {
+	MIX_NONE,
+	MIX_FMU,
+	MIX_OVERRIDE,
+	MIX_FAILSAFE
+};
+static mixer_source source;
+
+static int	mixer_callback(uintptr_t handle,
+			       uint8_t control_group,
+			       uint8_t control_index,
+			       float &control);
+
+static MixerGroup mixer_group(mixer_callback, 0);
+
+void
+mixer_tick(void)
+{
+	/* check that we are receiving fresh data from the FMU */
+	if (hrt_elapsed_time(&system_state.fmu_data_received_time) > FMU_INPUT_DROP_LIMIT_US) {
+
+		/* too long without FMU input, time to go to failsafe */
+		if (r_status_flags & PX4IO_P_STATUS_FLAGS_FMU_OK) {
+			isr_debug(1, "AP RX timeout");
+		}
+		r_status_flags &= ~(PX4IO_P_STATUS_FLAGS_FMU_OK | PX4IO_P_STATUS_FLAGS_RAW_PWM);
+		r_status_alarms |= PX4IO_P_STATUS_ALARMS_FMU_LOST;
+
+	} else {
+		r_status_flags |= PX4IO_P_STATUS_FLAGS_FMU_OK;
+		r_status_alarms &= ~PX4IO_P_STATUS_ALARMS_FMU_LOST;
+	}
+
+	source = MIX_FAILSAFE;
+
+	/*
+	 * Decide which set of controls we're using.
+	 */
+	if ((r_status_flags & PX4IO_P_STATUS_FLAGS_RAW_PWM) ||
+		!(r_status_flags & PX4IO_P_STATUS_FLAGS_MIXER_OK)) {
+
+		/* don't actually mix anything - we already have raw PWM values or
+		 not a valid mixer. */
+		source = MIX_NONE;
+
+	} else {
+
+		if (!(r_status_flags & PX4IO_P_STATUS_FLAGS_OVERRIDE) &&
+		     (r_status_flags & PX4IO_P_STATUS_FLAGS_MIXER_OK)) {
+
+			/* mix from FMU controls */
+			source = MIX_FMU;
+		}
+
+		if ( (r_status_flags & PX4IO_P_STATUS_FLAGS_OVERRIDE) &&
+		     (r_status_flags & PX4IO_P_STATUS_FLAGS_RC_OK) &&
+		     (r_status_flags & PX4IO_P_STATUS_FLAGS_MIXER_OK)) {
+
+		 	/* if allowed, mix from RC inputs directly */
+			source = MIX_OVERRIDE;
+		}
+	}
+
+	/*
+	 * Run the mixers.
+	 */
+	if (source == MIX_FAILSAFE) {
+
+		/* copy failsafe values to the servo outputs */
+		for (unsigned i = 0; i < IO_SERVO_COUNT; i++)
+			r_page_servos[i] = r_page_servo_failsafe[i];
+
+	} else if (source != MIX_NONE) {
+
+		float	outputs[IO_SERVO_COUNT];
+		unsigned mixed;
+
+		/* mix */
+		mixed = mixer_group.mix(&outputs[0], IO_SERVO_COUNT);
+
+		/* scale to PWM and update the servo outputs as required */
+		for (unsigned i = 0; i < mixed; i++) {
+
+			/* save actuator values for FMU readback */
+			r_page_actuators[i] = FLOAT_TO_REG(outputs[i]);
+
+			/* scale to servo output */
+			r_page_servos[i] = (outputs[i] * 500.0f) + 1500;
+
+		}
+		for (unsigned i = mixed; i < IO_SERVO_COUNT; i++)
+			r_page_servos[i] = 0;
+	}
+
+	/*
+	 * Decide whether the servos should be armed right now.
+	 *
+	 * We must be armed, and we must have a PWM source; either raw from
+	 * FMU or from the mixer.
+	 *
+	 * XXX correct behaviour for failsafe may require an additional case
+	 * here.
+	 */
+	bool should_arm = (
+	    /* FMU is armed */ (r_setup_arming & PX4IO_P_SETUP_ARMING_ARM_OK) &&
+	 	/* IO is armed */  (r_status_flags & PX4IO_P_STATUS_FLAGS_ARMED) &&
+		/* there is valid input */ (r_status_flags & (PX4IO_P_STATUS_FLAGS_RAW_PWM | PX4IO_P_STATUS_FLAGS_MIXER_OK)) &&
+		/* IO initialised without error */  (r_status_flags & PX4IO_P_STATUS_FLAGS_INIT_OK) &&
+		/* FMU is available or FMU is not available but override is an option */
+		((r_status_flags & PX4IO_P_STATUS_FLAGS_FMU_OK) || (!(r_status_flags & PX4IO_P_STATUS_FLAGS_FMU_OK) && (r_setup_arming & PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK) ))
+	);
+
+	if (should_arm && !mixer_servos_armed) {
+		/* need to arm, but not armed */
+		up_pwm_servo_arm(true);
+		mixer_servos_armed = true;
+
+	} else if (!should_arm && mixer_servos_armed) {
+		/* armed but need to disarm */
+		up_pwm_servo_arm(false);
+		mixer_servos_armed = false;
+	}
+
+	if (mixer_servos_armed) {
+		/* update the servo outputs. */
+		for (unsigned i = 0; i < IO_SERVO_COUNT; i++)
+			up_pwm_servo_set(i, r_page_servos[i]);
+	}
+}
+
+static int
+mixer_callback(uintptr_t handle,
+	       uint8_t control_group,
+	       uint8_t control_index,
+	       float &control)
+{
+	if (control_group != 0)
+		return -1;
+
+	switch (source) {
+	case MIX_FMU:
+		if (control_index < PX4IO_CONTROL_CHANNELS) {
+			control = REG_TO_FLOAT(r_page_controls[control_index]);
+			break;
+		}
+		return -1;
+
+	case MIX_OVERRIDE:
+		if (r_page_rc_input[PX4IO_P_RC_VALID] & (1 << control_index)) {
+			control = REG_TO_FLOAT(r_page_rc_input[PX4IO_P_RC_BASE + control_index]);
+			break;
+		}
+		return -1;
+
+	case MIX_FAILSAFE:
+	case MIX_NONE:
+		/* XXX we could allow for configuration of per-output failsafe values */
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * XXX error handling here should be more aggressive; currently it is
+ * possible to get STATUS_FLAGS_MIXER_OK set even though the mixer has
+ * not loaded faithfully.
+ */
+
+static char mixer_text[256];		/* large enough for one mixer */
+static unsigned mixer_text_length = 0;
+
+void
+mixer_handle_text(const void *buffer, size_t length)
+{
+	/* do not allow a mixer change while fully armed */
+	if (/* FMU is armed */ (r_setup_arming & PX4IO_P_SETUP_ARMING_ARM_OK) &&
+	    /* IO is armed */  (r_status_flags & PX4IO_P_STATUS_FLAGS_ARMED)) {
+		return;
+	}
+
+	px4io_mixdata	*msg = (px4io_mixdata *)buffer;
+
+	isr_debug(2, "mix txt %u", length);
+
+	if (length < sizeof(px4io_mixdata))
+		return;
+
+	unsigned	text_length = length - sizeof(px4io_mixdata);
+
+	switch (msg->action) {
+	case F2I_MIXER_ACTION_RESET:
+		isr_debug(2, "reset");
+
+		/* FIRST mark the mixer as invalid */
+		r_status_flags &= ~PX4IO_P_STATUS_FLAGS_MIXER_OK;
+		/* THEN actually delete it */
+		mixer_group.reset();
+		mixer_text_length = 0;
+
+		/* FALLTHROUGH */
+	case F2I_MIXER_ACTION_APPEND:
+		isr_debug(2, "append %d", length);
+
+		/* check for overflow - this is really fatal */
+		/* XXX could add just what will fit & try to parse, then repeat... */
+		if ((mixer_text_length + text_length + 1) > sizeof(mixer_text)) {
+			r_status_flags &= ~PX4IO_P_STATUS_FLAGS_MIXER_OK;
+			return;
+		}
+
+		/* append mixer text and nul-terminate */
+		memcpy(&mixer_text[mixer_text_length], msg->text, text_length);
+		mixer_text_length += text_length;
+		mixer_text[mixer_text_length] = '\0';
+		isr_debug(2, "buflen %u", mixer_text_length);
+
+		/* process the text buffer, adding new mixers as their descriptions can be parsed */
+		unsigned resid = mixer_text_length;
+		mixer_group.load_from_buf(&mixer_text[0], resid);
+
+		/* if anything was parsed */
+		if (resid != mixer_text_length) {
+
+			/* ideally, this should test resid == 0 ? */
+			r_status_flags |= PX4IO_P_STATUS_FLAGS_MIXER_OK;
+
+			isr_debug(2, "used %u", mixer_text_length - resid);
+
+			/* copy any leftover text to the base of the buffer for re-use */
+			if (resid > 0)
+				memcpy(&mixer_text[0], &mixer_text[mixer_text_length - resid], resid);
+
+			mixer_text_length = resid;
+		}
+
+		break;
+	}
+}