Linux: added ADC simulator

The sensor module is now able to run after the simulation modules are
started.

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

4 files changed, 350 insertions, 2 deletions

diff --git a/makefiles/linux/config_linux_default.mk b/makefiles/linux/config_linux_default.mk
index b7bfd9392..4cd7ac4e2 100644
--- a/makefiles/linux/config_linux_default.mk
+++ b/makefiles/linux/config_linux_default.mk
@@ -60,6 +60,7 @@ MODULES		+= lib/conversion
 MODULES		+= platforms/linux/px4_layer
 MODULES		+= platforms/linux/drivers/accelsim
 MODULES		+= platforms/linux/drivers/gyrosim
+MODULES		+= platforms/linux/drivers/adcsim
 
 #
 # Unit tests
diff --git a/src/platforms/linux/drivers/adcsim/adcsim.cpp b/src/platforms/linux/drivers/adcsim/adcsim.cpp
new file mode 100644
index 000000000..f676d03d9
--- /dev/null
+++ b/src/platforms/linux/drivers/adcsim/adcsim.cpp
@@ -0,0 +1,303 @@
+/****************************************************************************
+ *
+ *   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 adc.cpp
+ *
+ * Driver for the STM32 ADCSIM.
+ *
+ * This is a low-rate driver, designed for sampling things like voltages
+ * and so forth. It avoids the gross complexity of the NuttX ADCSIM driver.
+ */
+
+#include <px4_config.h>
+#include <px4_adc.h>
+#include <board_config.h>
+#include <drivers/device/device.h>
+
+#include <sys/types.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include <arch/board/board.h>
+#include <drivers/drv_hrt.h>
+#include <drivers/drv_adc.h>
+
+#include <systemlib/err.h>
+#include <systemlib/perf_counter.h>
+
+#include <uORB/topics/system_power.h>
+
+
+class ADCSIM : public device::VDev
+{
+public:
+	ADCSIM(uint32_t channels);
+	~ADCSIM();
+
+	virtual int		init();
+
+	virtual int		ioctl(device::px4_dev_handle_t *handlep, int cmd, unsigned long arg);
+	virtual ssize_t		read(device::px4_dev_handle_t *handlep, char *buffer, size_t len);
+
+protected:
+	virtual int		open_first(device::px4_dev_handle_t *handlep);
+	virtual int		close_last(device::px4_dev_handle_t *handlep);
+
+private:
+	static const hrt_abstime _tickrate = 10000;	/**< 100Hz base rate */
+	
+	hrt_call		_call;
+	perf_counter_t		_sample_perf;
+
+	unsigned		_channel_count;
+	adc_msg_s		*_samples;		/**< sample buffer */
+
+	orb_advert_t		_to_system_power;
+
+	/** work trampoline */
+	static void		_tick_trampoline(void *arg);
+
+	/** worker function */
+	void			_tick();
+
+	/**
+	 * Sample a single channel and return the measured value.
+	 *
+	 * @param channel		The channel to sample.
+	 * @return			The sampled value, or 0xffff if
+	 *				sampling failed.
+	 */
+	uint16_t		_sample(unsigned channel);
+
+	// update system_power ORB topic, only on FMUv2
+	void update_system_power(void);
+};
+
+ADCSIM::ADCSIM(uint32_t channels) :
+	VDev("adc", ADCSIM0_DEVICE_PATH),
+	_sample_perf(perf_alloc(PC_ELAPSED, "adc_samples")),
+	_channel_count(0),
+	_samples(nullptr),
+	_to_system_power(0)
+{
+	_debug_enabled = true;
+
+	/* always enable the temperature sensor */
+	channels |= 1 << 16;
+
+	/* allocate the sample array */
+	for (unsigned i = 0; i < 32; i++) {
+		if (channels & (1 << i)) {
+			_channel_count++;
+		}
+	}
+	_samples = new adc_msg_s[_channel_count];
+
+	/* prefill the channel numbers in the sample array */
+	if (_samples != nullptr) {
+		unsigned index = 0;
+		for (unsigned i = 0; i < 32; i++) {
+			if (channels & (1 << i)) {
+				_samples[index].am_channel = i;
+				_samples[index].am_data = 0;
+				index++;
+			}
+		}
+	}
+}
+
+ADCSIM::~ADCSIM()
+{
+	if (_samples != nullptr)
+		delete _samples;
+}
+
+int
+ADCSIM::init()
+{
+	debug("init done");
+
+	/* create the device node */
+	return VDev::init();
+}
+
+int
+ADCSIM::ioctl(device::px4_dev_handle_t *handlep, int cmd, unsigned long arg)
+{
+	return -ENOTTY;
+}
+
+ssize_t
+ADCSIM::read(device::px4_dev_handle_t *handlep, char *buffer, size_t len)
+{
+	const size_t maxsize = sizeof(adc_msg_s) * _channel_count;
+
+	if (len > maxsize)
+		len = maxsize;
+
+	/* block interrupts while copying samples to avoid racing with an update */
+	memcpy(buffer, _samples, len);
+
+	return len;
+}
+
+int
+ADCSIM::open_first(device::px4_dev_handle_t *handlep)
+{
+	/* get fresh data */
+	_tick();
+
+	/* and schedule regular updates */
+	hrt_call_every(&_call, _tickrate, _tickrate, _tick_trampoline, this);
+
+	return 0;
+}
+
+int
+ADCSIM::close_last(device::px4_dev_handle_t *handlep)
+{
+	hrt_cancel(&_call);
+	return 0;
+}
+
+void
+ADCSIM::_tick_trampoline(void *arg)
+{
+	(reinterpret_cast<ADCSIM *>(arg))->_tick();
+}
+
+void
+ADCSIM::_tick()
+{
+	/* scan the channel set and sample each */
+	for (unsigned i = 0; i < _channel_count; i++)
+		_samples[i].am_data = _sample(_samples[i].am_channel);
+	update_system_power();
+}
+
+void
+ADCSIM::update_system_power(void)
+{
+}
+
+uint16_t
+ADCSIM::_sample(unsigned channel)
+{
+	perf_begin(_sample_perf);
+
+	uint16_t result = 1;
+
+	perf_end(_sample_perf);
+	return result;
+}
+
+/*
+ * Driver 'main' command.
+ */
+extern "C" __EXPORT int adc_main(int argc, char *argv[]);
+
+namespace
+{
+ADCSIM	*g_adc;
+
+int
+test(void)
+{
+
+	int fd = px4_open(ADCSIM0_DEVICE_PATH, O_RDONLY);
+	if (fd < 0) {
+		warnx("can't open ADCSIM device");
+		return 1;
+	}
+
+	for (unsigned i = 0; i < 50; i++) {
+		adc_msg_s data[12];
+		ssize_t count = read(fd, data, sizeof(data));
+
+		if (count < 0) {
+			warnx("read error");
+			return 1;
+		}
+
+		unsigned channels = count / sizeof(data[0]);
+
+		for (unsigned j = 0; j < channels; j++) {
+			printf ("%d: %u  ", data[j].am_channel, data[j].am_data);
+		}
+
+		printf("\n");
+		usleep(500000);
+	}
+
+	px4_close(fd);
+	return 0;
+}
+}
+
+int
+adc_main(int argc, char *argv[])
+{
+	int ret = 0;
+
+	if (g_adc == nullptr) {
+#ifdef CONFIG_ARCH_BOARD_LINUXTEST
+		/* XXX this hardcodes the default channel set for LINUXTEST - should be configurable */
+		g_adc = new ADCSIM((1 << 10) | (1 << 11) | (1 << 12) | (1 << 13));
+#endif
+
+		if (g_adc == nullptr) {
+			warnx("couldn't allocate the ADCSIM driver");
+			return 1;
+		}
+
+		if (g_adc->init() != OK) {
+			delete g_adc;
+			warnx("ADCSIM init failed");
+			return 1;
+		}
+	}
+
+	if (argc > 1) {
+		if (!strcmp(argv[1], "test"))
+			ret = test();
+	}
+
+	return ret;
+}
diff --git a/src/platforms/linux/drivers/adcsim/module.mk b/src/platforms/linux/drivers/adcsim/module.mk
new file mode 100644
index 000000000..9b8461fd7
--- /dev/null
+++ b/src/platforms/linux/drivers/adcsim/module.mk
@@ -0,0 +1,42 @@
+############################################################################
+#
+#   Copyright (c) 2012, 2013 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.
+#
+############################################################################
+
+#
+# STM32 ADC driver
+#
+
+MODULE_COMMAND	= adc
+
+SRCS		= adcsim.cpp
+
+MAXOPTIMIZATION	 = -Os
diff --git a/src/platforms/px4_adc.h b/src/platforms/px4_adc.h
index 0b123ed0c..bda39d036 100644
--- a/src/platforms/px4_adc.h
+++ b/src/platforms/px4_adc.h
@@ -39,6 +39,8 @@
 
 #pragma once
 
+#include <stdint.h>
+
 #if defined(__PX4_ROS)
 #error "ADC not supported in ROS"
 #elif defined(__PX4_NUTTX)
@@ -54,13 +56,13 @@ struct adc_msg_s
 {
   uint8_t      am_channel;               /* The 8-bit ADC Channel */
   int32_t      am_data;                  /* ADC convert result (4 bytes) */
-} packed_struct;
+} __attribute__ ((packed));
 
 // Example settings 
 #define ADC_BATTERY_VOLTAGE_CHANNEL     10
 #define ADC_BATTERY_CURRENT_CHANNEL     -1
 #define ADC_AIRSPEED_VOLTAGE_CHANNEL    11
-
+#define ADCSIM0_DEVICE_PATH	"/dev/adc0"
 #else
 #error "No target platform defined"
 #endif