IO firmware: Convert magic numbers to defines

This is necessary to allow more and better unit testing.

src/modules/px4iofirmware/mixer.cpp

@@ -465,7 +465,7 @@ mixer_callback(uintptr_t handle,
  * not loaded faithfully.
  */
 
-static char mixer_text[200];		/* large enough for one mixer */
+static char mixer_text[PX4IO_MAX_MIXER_LENGHT];		/* large enough for one mixer */
 static unsigned mixer_text_length = 0;
 
 int

src/modules/px4iofirmware/mixer.h

@@ -0,0 +1,42 @@
+/****************************************************************************
+ *
+ *   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.
+ *
+ ****************************************************************************/
+
+/**
+ * @file mixer.h
+ *
+ * PX4IO mixer definitions
+ *
+ * @author Lorenz Meier <lorenz@px4.io>
+ */
+#pragma once
+#define PX4IO_MAX_MIXER_LENGHT		230

src/modules/px4iofirmware/protocol.h

@@ -82,16 +82,17 @@
 #define PX4IO_PROTOCOL_MAX_CONTROL_COUNT	8	/**< The protocol does not support more than set here, individual units might support less - see PX4IO_P_CONFIG_CONTROL_COUNT */
 
 /* static configuration page */
-#define PX4IO_PAGE_CONFIG		0
+#define PX4IO_PAGE_CONFIG					0
 #define PX4IO_P_CONFIG_PROTOCOL_VERSION		0	/* PX4IO_PROTOCOL_VERSION */
 #define PX4IO_P_CONFIG_HARDWARE_VERSION		1	/* magic numbers TBD */
 #define PX4IO_P_CONFIG_BOOTLOADER_VERSION	2	/* get this how? */
-#define PX4IO_P_CONFIG_MAX_TRANSFER		3	/* maximum I2C transfer size */
+#define PX4IO_P_CONFIG_MAX_TRANSFER			3	/* maximum I2C transfer size */
 #define PX4IO_P_CONFIG_CONTROL_COUNT		4	/* hardcoded max control count supported */
 #define PX4IO_P_CONFIG_ACTUATOR_COUNT		5	/* hardcoded max actuator output count */
 #define PX4IO_P_CONFIG_RC_INPUT_COUNT		6	/* hardcoded max R/C input count supported */
 #define PX4IO_P_CONFIG_ADC_INPUT_COUNT		7	/* hardcoded max ADC inputs */
-#define PX4IO_P_CONFIG_RELAY_COUNT		8	/* hardcoded # of relay outputs */
+#define PX4IO_P_CONFIG_RELAY_COUNT			8	/* hardcoded # of relay outputs */
+#define PX4IO_MAX_TRANSFER_LEN				64
 
 /* dynamic status page */
 #define PX4IO_PAGE_STATUS		1
@@ -338,6 +339,10 @@ struct IOPacket {
 };
 #pragma pack(pop)
 
+#if (PX4IO_MAX_TRANSFER_LEN > PKT_MAX_REGS * 2)
+#error The max transfer length of the IO protocol must not be larger than the IO packet size
+#endif
+
 #define PKT_CODE_READ		0x00	/* FMU->IO read transaction */
 #define PKT_CODE_WRITE		0x40	/* FMU->IO write transaction */
 #define PKT_CODE_SUCCESS	0x00	/* IO->FMU success reply */

src/modules/px4iofirmware/px4io.h

@@ -57,7 +57,8 @@
 /*
  * Constants and limits.
  */
-#define PX4IO_SERVO_COUNT		8
+#define PX4IO_BL_VERSION			3
+#define PX4IO_SERVO_COUNT			8
 #define PX4IO_CONTROL_CHANNELS		8
 #define PX4IO_CONTROL_GROUPS		4
 #define PX4IO_RC_INPUT_CHANNELS		18

src/modules/px4iofirmware/registers.c

@@ -69,8 +69,8 @@ static const uint16_t	r_page_config[] = {
 #else
 	[PX4IO_P_CONFIG_HARDWARE_VERSION]	= 1,
 #endif
-	[PX4IO_P_CONFIG_BOOTLOADER_VERSION]	= 3,	/* XXX hardcoded magic number */
+	[PX4IO_P_CONFIG_BOOTLOADER_VERSION]	= PX4IO_BL_VERSION,
-	[PX4IO_P_CONFIG_MAX_TRANSFER]		= 64,	/* XXX hardcoded magic number */
+	[PX4IO_P_CONFIG_MAX_TRANSFER]		= PX4IO_MAX_TRANSFER_LEN,
 	[PX4IO_P_CONFIG_CONTROL_COUNT]		= PX4IO_CONTROL_CHANNELS,
 	[PX4IO_P_CONFIG_ACTUATOR_COUNT]		= PX4IO_SERVO_COUNT,
 	[PX4IO_P_CONFIG_RC_INPUT_COUNT]		= PX4IO_RC_INPUT_CHANNELS,