From 3a880a09d64c999d9e1b25e72fd2da8d0d1d8b4d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Beat=20K=C3=BCng?= <beat-kueng@gmx.net>
Date: Thu, 4 May 2017 16:39:51 +0200
Subject: [PATCH] mixer: add documentation

---
 src/systemcmds/mixer/mixer.cpp | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/src/systemcmds/mixer/mixer.cpp b/src/systemcmds/mixer/mixer.cpp
index 996a220b91..40668cf156 100644
--- a/src/systemcmds/mixer/mixer.cpp
+++ b/src/systemcmds/mixer/mixer.cpp
@@ -38,6 +38,7 @@
  */
 
 #include <px4_config.h>
+#include <px4_module.h>
 #include <px4_posix.h>
 #include <string.h>
 #include <stdlib.h>
@@ -47,7 +48,6 @@
 #include <errno.h>
 #include <ctype.h>
 
-#include <systemlib/err.h>
 #include <systemlib/mixer/mixer.h>
 #include <uORB/topics/actuator_controls.h>
 
@@ -110,8 +110,21 @@ usage(const char *reason)
 		PX4_INFO("%s", reason);
 	}
 
-	PX4_INFO("usage:");
-	PX4_INFO("  mixer load <device> <filename>");
+	PRINT_MODULE_DESCRIPTION(
+		R"DESCR_STR(
+### Description
+Load or append mixer files to the ESC driver.
+
+Note that the driver must support the used ioctl's, which is the case on NuttX, but for example not on the RPi.
+)DESCR_STR");
+
+
+	PRINT_MODULE_USAGE_NAME("mixer", "command");
+
+	PRINT_MODULE_USAGE_COMMAND("load");
+	PRINT_MODULE_USAGE_ARG("<file:dev> <file>", "Output device (eg. /dev/pwm_output0) and mixer file", false);
+	PRINT_MODULE_USAGE_COMMAND("append");
+	PRINT_MODULE_USAGE_ARG("<file:dev> <file>", "Output device (eg. /dev/pwm_output0) and mixer file", false);
 }
 
 static int