Add a watchdog timer test

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4614 42af7a65-404d-4744-a932-0658087f49c3

11 files changed, 685 insertions, 15 deletions

diff --git a/apps/ChangeLog.txt b/apps/ChangeLog.txt
index 182fa50f2..a70a9406d 100755
--- a/apps/ChangeLog.txt
+++ b/apps/ChangeLog.txt
@@ -224,4 +224,5 @@
 
 	* Kconfig:  Continued Kconfig file updates (no longer tracking on a per-file
 	  basis in the ChangeLog)
+	* apps/examples/watchdog:  Add a watchdog timer example.
 
diff --git a/apps/examples/Kconfig b/apps/examples/Kconfig
index 702d8d4da..fbbe6d583 100644
--- a/apps/examples/Kconfig
+++ b/apps/examples/Kconfig
@@ -183,6 +183,10 @@ menu "USB serial terminal example"
 source "$APPSDIR/examples/usbterm/Kconfig"
 endmenu
 
+menu "Watchdog timer example"
+source "$APPSDIR/examples/watchdog/Kconfig"
+endmenu
+
 menu "wget example"
 source "$APPSDIR/examples/wget/Kconfig"
 endmenu
diff --git a/apps/examples/Makefile b/apps/examples/Makefile
index 838b70699..7ad8d82bc 100644
--- a/apps/examples/Makefile
+++ b/apps/examples/Makefile
@@ -41,7 +41,7 @@ SUBDIRS = adc buttons can cdcacm composite dhcpd ftpc ftpd hello helloxx \
 	hidkbd igmp lcdrw mm mount nettest nsh null nx nxconsole nxffs nxflat \
 	nxhello nximage nxlines nxtext ostest pashello pipe poll pwm qencoder \
 	rgmp romfs serloop telnetd thttpd tiff touchscreen udp uip usbserial \
-	sendmail usbstorage usbterm wget wlan
+	sendmail usbstorage usbterm watchdog wget wlan
 
 # Sub-directories that might need context setup.  Directories may need
 # context setup for a variety of reasons, but the most common is because
@@ -56,7 +56,7 @@ SUBDIRS = adc buttons can cdcacm composite dhcpd ftpc ftpd hello helloxx \
 CNTXTDIRS = pwm
 
 ifeq ($(CONFIG_NSH_BUILTIN_APPS),y)
-CNTXTDIRS += adc can cdcacm composite ftpd dhcpd nettest qencoder telnetd
+CNTXTDIRS += adc can cdcacm composite ftpd dhcpd nettest qencoder telnetd watchdog
 endif
 
 ifeq ($(CONFIG_EXAMPLES_HELLO_BUILTIN),y)
diff --git a/apps/examples/README.txt b/apps/examples/README.txt
index ec636cd6d..06236180c 100644
--- a/apps/examples/README.txt
+++ b/apps/examples/README.txt
@@ -1036,11 +1036,11 @@ examples/pwm
     CONFIG_EXAMPLES_PWM_DEVPATH - The path to the PWM device. Default: /dev/pwm0
     CONFIG_EXAMPLES_PWM_FREQUENCY - The initial PWM frequency.  Default: 100 Hz
     CONFIG_EXAMPLES_PWM_DUTYPCT - The initial PWM duty as a percentage.  Default: 50%
-    CONFIG_EXAMPLES_PWM_DURATION - The initial PWM pulse train duration in sectonds.
-       as a percentage. Used only if the current pulse count is zero (pulse count
-       is only supported if CONFIG_PWM_PULSECOUNT is defined). Default: 5 seconds
-    CONFIG_EXAMPLES_PWM_COUNT - The initial PWM pulse count.  This option is
-       only available if CONFIG_PWM_PULSECOUNT is defined. Default: 0 (i.e., use
+    CONFIG_EXAMPLES_PWM_DURATION - The initial PWM pulse train duration in seconds.
+       Used only if the current pulse count is zero (pulse count is only supported
+       if CONFIG_PWM_PULSECOUNT is defined). Default: 5 seconds
+    CONFIG_EXAMPLES_PWM_PULSECOUNT - The initial PWM pulse count.  This option is
+       only available if CONFIG_PWM_PULSECOUNT is non-zero. Default: 0 (i.e., use
        the duration, not the count).
 
 examples/qencoder
@@ -1550,6 +1550,35 @@ examples/usbterm
   Prolifics emulation (not defined) and the CDC serial implementation
   (when defined). CONFIG_USBDEV_TRACE_INITIALIDSET.
 
+examples/watchdog
+^^^^^^^^^^^^^^^^^
+
+  A simple test of a watchdog timer driver.  Initializes starts the watchdog
+  timer.  It pings the watchdog timer for a period of time then lets the
+  watchdog timer expire... resetting the CPU is successful.  This
+  example can ONLY be built as an NSH built-in function.
+
+  This test depends on these specific Watchdog/NSH configurations settings (your
+  specific watchdog hardware settings might require additional settings).
+
+    CONFIG_WATCHDOG- Enables watchdog timer support support.
+    CONFIG_NSH_BUILTIN_APPS - Build the watchdog time test as an NSH
+      built-in function. Default: Not built!  The example can only be used
+      as an NSH built-in application
+ 
+  Specific configuration options for this example include:
+ 
+    CONFIG_EXAMPLES_WATCHDOG_DEVPATH - The path to the Watchdog device.
+      Default: /dev/watchdog0
+    CONFIG_EXAMPLES_WATCHDOG_PINGTIME - Time in milliseconds that the example
+      will ping the watchdog before letting the watchdog expire. Default: 5000
+      milliseconds
+    CONFIG_EXAMPLES_WATCHDOG_PINGDELAY - Time delay between pings in
+      milliseconds. Default: 500 milliseconds.
+    CONFIG_EXAMPLES_WATCHDOG_TIMEOUT - The watchdog timeout value in
+      milliseconds before the watchdog timer expires.  Default:  2000
+      milliseconds.
+
 examples/wget
 ^^^^^^^^^^^^^
 
diff --git a/apps/examples/pwm/Kconfig b/apps/examples/pwm/Kconfig
index 593136f26..78edd2178 100644
--- a/apps/examples/pwm/Kconfig
+++ b/apps/examples/pwm/Kconfig
@@ -6,8 +6,43 @@
 config EXAMPLES_PWM
 	bool "Pulse width modulation (PWM) example"
 	default n
+	depends on PWM && NSH_BUILTIN_APPS
 	---help---
 		Enable the Pulse width modulation (PWM) example
 
 if EXAMPLES_PWM
+
+config EXAMPLES_PWM_DEVPATH
+	string "PWM device path"
+	default "/dev/pwm0"
+	---help---
+		The path to the PWM device. Default: /dev/pwm0
+
+config EXAMPLES_PWM_FREQUENCY
+	int "Default PWM freququency"
+	default 100
+	---help---
+		The default PWM frequency.  Default: 100 Hz
+
+config EXAMPLES_PWM_DUTYPCT
+	int "Default PWM duty percentage"
+	default 50
+	---help---
+		The default PWM duty as a percentage.  Default: 50%
+
+config EXAMPLES_PWM_DURATION
+	int "Default PWM duration"
+	default 5 if !EXAMPLES_PWM_PULSECOUNT
+	---help---
+		The default PWM pulse train duration in seconds.  Used only if the current
+		pulse count is zero (pulse countis only supported if CONFIG_PWM_PULSECOUNT
+		is defined). Default: 5 seconds
+
+config EXAMPLES_PWM_PULSECOUNT
+	int "Default pulse count"
+	default 0
+	---help---
+	The initial PWM pulse count.  This option is only available if CONFIG_PWM_PULSECOUNT
+	is nonzero. Default: 0 (i.e., use the duration, not the count).
+
 endif
diff --git a/apps/examples/pwm/Makefile b/apps/examples/pwm/Makefile
index 3c9c243cb..efbdb048e 100644
--- a/apps/examples/pwm/Makefile
+++ b/apps/examples/pwm/Makefile
@@ -37,7 +37,7 @@
 -include $(TOPDIR)/Make.defs
 include $(APPDIR)/Make.defs
 
-# NuttX NX Graphics Example.
+# PWM Example.
 
 ASRCS		=
 CSRCS		= pwm_main.c
@@ -56,7 +56,7 @@ endif
 
 ROOTDEPPATH	= --dep-path .
 
-# Touchscreen built-in application info
+# PWM built-in application info
 
 APPNAME		= pwm
 PRIORITY	= SCHED_PRIORITY_DEFAULT
diff --git a/apps/examples/pwm/pwm.h b/apps/examples/pwm/pwm.h
index e15b933fc..5c049a8f8 100644
--- a/apps/examples/pwm/pwm.h
+++ b/apps/examples/pwm/pwm.h
@@ -1,7 +1,7 @@
 /****************************************************************************
- * examples/examples/pwm.h
+ * examples/examples/pwm/pwm.h
  *
- *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2011-2012 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -52,10 +52,10 @@
  * CONFIG_EXAMPLES_PWM_DEVPATH - The path to the PWM device. Default: /dev/pwm0
  * CONFIG_EXAMPLES_PWM_FREQUENCY - The initial PWM frequency.  Default: 100 Hz
  * CONFIG_EXAMPLES_PWM_DUTYPCT - The initial PWM duty as a percentage.  Default: 50%
- * CONFIG_EXAMPLES_PWM_DURATION - The initial PWM pulse train duration in sectonds.
- *   as a percentage. Used only if the current pulse count is zero (pulse count
- *   is only supported if CONFIG_PWM_PULSECOUNT is defined). Default: 5 seconds
- * CONFIG_EXAMPLES_PWM_COUNT - The initial PWM pulse count.  This option is
+ * CONFIG_EXAMPLES_PWM_DURATION - The initial PWM pulse train duration in seconds.
+ *   Used only if the current pulse count is zero (pulse count is only supported
+ *   if CONFIG_PWM_PULSECOUNT is defined). Default: 5 seconds
+ * CONFIG_EXAMPLES_PWM_PULSECOUNT - The initial PWM pulse count.  This option is
  *   only available if CONFIG_PWM_PULSECOUNT is defined. Default: 0 (i.e., use
  *   the duration, not the count).
  */
diff --git a/apps/examples/watchdog/Kconfig b/apps/examples/watchdog/Kconfig
new file mode 100644
index 000000000..18daf9327
--- /dev/null
+++ b/apps/examples/watchdog/Kconfig
@@ -0,0 +1,40 @@
+#
+# For a description of the syntax of this configuration file,
+# see misc/tools/kconfig-language.txt.
+#
+
+config EXAMPLES_WATCHDOG
+	bool "Watchdog Timer example"
+	default n
+	---help---
+		Enable the watchdog timer example
+
+if EXAMPLES_WATCHDOG
+
+config EXAMPLES_WATCHDOG_DEVPATH
+	string "Watchdog device path"
+	default "/dev/watchdog0"
+	---help---
+		The path to the watchdog device. Default: /dev/watchdog0
+
+config CONFIG_EXAMPLES_WATCHDOG_PINGTIME
+	int "Watchdog ping time"
+	default 5000
+	---help---
+		Time in milliseconds that the example will ping the watchdog before letting the
+		watchdog expire. Default: 5000 milliseconds.
+
+config CONFIG_EXAMPLES_WATCHDOG_PINGDELAY
+	int "Watchdog ping delay"
+	default 500
+	---help---
+		Time delay between pings in milliseconds. Default: 500 milliseconds.
+
+config EXAMPLES_WATCHDOG_TIMEOUT
+	int "Watchdog timeout"
+	default 2000
+	---help---
+		The watchdog timeout value in milliseconds before the watchdog timer
+		expires.  Default:  2000 milliseconds.
+
+endif
diff --git a/apps/examples/watchdog/Makefile b/apps/examples/watchdog/Makefile
new file mode 100644
index 000000000..d2739dbb0
--- /dev/null
+++ b/apps/examples/watchdog/Makefile
@@ -0,0 +1,103 @@
+############################################################################
+# apps/examples/watchdog/Makefile
+#
+#   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+#   Author: Gregory Nutt <gnutt@nuttx.org>
+#
+# 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 NuttX 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.
+#
+############################################################################
+
+-include $(TOPDIR)/.config
+-include $(TOPDIR)/Make.defs
+include $(APPDIR)/Make.defs
+
+# Watchdog Timer Example.
+
+ASRCS		=
+CSRCS		= watchdog_main.c
+
+AOBJS		= $(ASRCS:.S=$(OBJEXT))
+COBJS		= $(CSRCS:.c=$(OBJEXT))
+
+SRCS		= $(ASRCS) $(CSRCS)
+OBJS		= $(AOBJS) $(COBJS)
+
+ifeq ($(WINTOOL),y)
+  BIN		= "${shell cygpath -w  $(APPDIR)/libapps$(LIBEXT)}"
+else
+  BIN		= "$(APPDIR)/libapps$(LIBEXT)"
+endif
+
+ROOTDEPPATH	= --dep-path .
+
+# Touchscreen built-in application info
+
+APPNAME		= wdog
+PRIORITY	= SCHED_PRIORITY_DEFAULT
+STACKSIZE	= 2048
+
+# Common build
+
+VPATH		= 
+
+all: .built
+.PHONY: context clean depend distclean
+
+$(AOBJS): %$(OBJEXT): %.S
+	$(call ASSEMBLE, $<, $@)
+
+$(COBJS): %$(OBJEXT): %.c
+	$(call COMPILE, $<, $@)
+
+.built: $(OBJS)
+	@( for obj in $(OBJS) ; do \
+		$(call ARCHIVE, $(BIN), $${obj}); \
+	done ; )
+	@touch .built
+
+.context:
+	$(call REGISTER,$(APPNAME),$(PRIORITY),$(STACKSIZE),$(APPNAME)_main)
+	@touch $@
+
+context: .context
+
+.depend: Makefile $(SRCS)
+	@$(MKDEP) $(ROOTDEPPATH) $(CC) -- $(CFLAGS) -- $(SRCS) >Make.dep
+	@touch $@
+
+depend: .depend
+
+clean:
+	@rm -f *.o *~ .*.swp .built
+	$(call CLEAN)
+
+distclean: clean
+	@rm -f Make.dep .depend
+
+-include Make.dep
diff --git a/apps/examples/watchdog/watchdog.h b/apps/examples/watchdog/watchdog.h
new file mode 100644
index 000000000..1b36da9b4
--- /dev/null
+++ b/apps/examples/watchdog/watchdog.h
@@ -0,0 +1,132 @@
+/****************************************************************************
+ * examples/examples/watchdog/watchdog.h
+ *
+ *   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * 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 NuttX 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.
+ *
+ ****************************************************************************/
+
+#ifndef __APPS_EXAMPLES_WATCHDOG_WATCHDOG_H
+#define __APPS_EXAMPLES_WATCHDOG_WATCHDOG_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+/* Configuration ************************************************************/
+/* CONFIG_NSH_BUILTIN_APPS - Build the WATCHDOG test as an NSH built-in
+ *   function. Default: Not built!  The example can only be used as an NSH
+ *   built-in application
+ * CONFIG_EXAMPLES_WATCHDOG_DEVPATH - The path to the Watchdog device.
+ *   Default: /dev/watchdog0
+ * CONFIG_EXAMPLES_WATCHDOG_PINGTIME - Time in milliseconds that the example
+ *   will ping the watchdog before letting the watchdog expire. Default: 5000
+ *   milliseconds
+ * CONFIG_EXAMPLES_WATCHDOG_PINGDELAY - Time delay between pings in
+ *   milliseconds. Default: 500 milliseconds.
+ * CONFIG_EXAMPLES_WATCHDOG_TIMEOUT - The watchdog timeout value in
+ *   milliseconds before the watchdog timer expires.  Default:  2000
+ *   milliseconds.
+ */
+
+#ifndef CONFIG_WATCHDOG
+#  error "WATCHDOG device support is not enabled (CONFIG_WATCHDOG)"
+#endif
+
+#ifndef CONFIG_NSH_BUILTIN_APPS
+#  warning "The WATCHDOG example only works as an NSH built-in application (CONFIG_NSH_BUILTIN_APPS)"
+#endif
+
+#ifndef CONFIG_EXAMPLES_WATCHDOG_DEVPATH
+#  define CONFIG_EXAMPLES_WATCHDOG_DEVPATH "/dev/watchdog0"
+#endif
+
+#ifndef CONFIG_EXAMPLES_WATCHDOG_PINGTIME
+#  define CONFIG_EXAMPLES_WATCHDOG_PINGTIME 5000
+#endif
+
+#ifndef CONFIG_EXAMPLES_WATCHDOG_PINGDELAY
+#  define CONFIG_EXAMPLES_WATCHDOG_PINGDELAY 500
+#endif
+
+#ifndef CONFIG_EXAMPLES_WATCHDOG_TIMEOUT
+#  define CONFIG_EXAMPLES_WATCHDOG_TIMEOUT 2000
+#endif
+
+/* Debug ********************************************************************/
+
+#ifdef CONFIG_CPP_HAVE_VARARGS
+#  ifdef CONFIG_DEBUG
+#    define message(...) lib_rawprintf(__VA_ARGS__)
+#    define msgflush()
+#  else
+#    define message(...) printf(__VA_ARGS__)
+#    define msgflush() fflush(stdout)
+#  endif
+#else
+#  ifdef CONFIG_DEBUG
+#    define message lib_rawprintf
+#    define msgflush()
+#  else
+#    define message printf
+#    define msgflush() fflush(stdout)
+#  endif
+#endif
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: watchdog_devinit()
+ *
+ * Description:
+ *   Perform architecuture-specific initialization of the Watchdog hardware.
+ *   This interface must be provided by all configurations using
+ *   apps/examples/watchdog
+ *
+ ****************************************************************************/
+
+int watchdog_devinit(void);
+
+#endif /* __APPS_EXAMPLES_WATCHDOG_WATCHDOG_H */
diff --git a/apps/examples/watchdog/watchdog_main.c b/apps/examples/watchdog/watchdog_main.c
new file mode 100644
index 000000000..6d1e1c43a
--- /dev/null
+++ b/apps/examples/watchdog/watchdog_main.c
@@ -0,0 +1,326 @@
+/****************************************************************************
+ * examples/watchdog/watchdog_main.c
+ *
+ *   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * 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 NuttX 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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <sys/ioctl.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/watchdog.h>
+
+#include "watchdog.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+struct wdog_example_s
+{
+  uint32_t pingtime;
+  uint32_t pingdelay;
+  uint32_t timeout;
+};
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: wdog_help
+ ****************************************************************************/
+
+static void wdog_help(void)
+{
+  message("Usage: wdog [-h] [-d <pingtime] [-p <pingdelay>] [-t <timeout>]\n");
+  message("\nInitialize the watchdog to the <timeout>.  Start the watchdog\n");
+  message("timer.  Ping for the watchdog for <pingtime> seconds, then let it expire.\n");
+  message("\nOptions include:\n");
+  message("  [-d <pingtime>] = Selects the <delay> time in milliseconds.  Default: %d\n",
+         CONFIG_EXAMPLES_WATCHDOG_PINGTIME);
+  message("  [-p <pingdelay] = Time delay between pings in milliseconds.  Default: %d\n",
+         CONFIG_EXAMPLES_WATCHDOG_PINGDELAY);
+  message("  [-t timeout] = Time in milliseconds that the example will ping the watchdog\n");
+  message("    before letting the watchdog expire. Default: %d\n",
+          CONFIG_EXAMPLES_WATCHDOG_TIMEOUT);
+  message("  [-h] = Shows this message and exits\n");
+}
+
+/****************************************************************************
+ * Name: arg_string
+ ****************************************************************************/
+
+static int arg_string(FAR char **arg, FAR char **value)
+{
+  FAR char *ptr = *arg;
+
+  if (ptr[2] == '\0')
+    {
+      *value = arg[1];
+      return 2;
+    }
+  else
+    {
+      *value = &ptr[2];
+      return 1;
+    }
+}
+
+/****************************************************************************
+ * Name: arg_decimal
+ ****************************************************************************/
+
+static int arg_decimal(FAR char **arg, FAR long *value)
+{
+  FAR char *string;
+  int ret;
+
+  ret = arg_string(arg, &string);
+  *value = strtol(string, NULL, 10);
+  return ret;
+}
+
+/****************************************************************************
+ * Name: parse_args
+ ****************************************************************************/
+
+static void parse_args(FAR struct wdog_example_s *wdog, int argc, FAR char **argv)
+{
+  FAR char *ptr;
+  long value;
+  int index;
+  int nargs;
+ 
+  wdog->pingtime  = CONFIG_EXAMPLES_WATCHDOG_PINGTIME;
+  wdog->pingdelay = CONFIG_EXAMPLES_WATCHDOG_PINGDELAY;
+  wdog->timeout   = CONFIG_EXAMPLES_WATCHDOG_TIMEOUT;
+
+  for (index = 1; index < argc; )
+    {
+      ptr = argv[index];
+      if (ptr[0] != '-')
+        {
+          message("Invalid options format: %s\n", ptr);
+          exit(EXIT_SUCCESS);
+        }
+
+      switch (ptr[1])
+        {
+          case 'd':
+            nargs = arg_decimal(&argv[index], &value);
+            if (value < 1)
+              {
+                message("Ping delay out of range: %ld\n", value);
+                exit(EXIT_FAILURE);
+              }
+
+            wdog->pingdelay = (uint32_t)value;
+            index += nargs;
+            break;
+
+          case 'p':
+            nargs = arg_decimal(&argv[index], &value);
+            if (value < 1 || value > 99)
+              {
+                message("Ping time out of range: %ld\n", value);
+                exit(EXIT_FAILURE);
+              }
+
+            wdog->pingtime = (uint8_t)value;
+            index += nargs;
+            break;
+
+          case 't':
+            nargs = arg_decimal(&argv[index], &value);
+            if (value < 1 || value > INT_MAX)
+              {
+                message("Duration out of range: %ld\n", value);
+                exit(EXIT_FAILURE);
+              }
+
+            wdog->timeout = (int)value;
+            index += nargs;
+            break;
+
+          case 'h':
+            wdog_help();
+            exit(EXIT_SUCCESS);
+        
+          default:
+            message("Unsupported option: %s\n", ptr);
+            wdog_help();
+            exit(EXIT_FAILURE);
+        }
+    }
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: user_start/wdog_main
+ ****************************************************************************/
+
+int wdog_main(int argc, char *argv[])
+{
+  struct wdog_example_s wdog;
+  uint32_t elapsed;
+  int fd;
+  int ret;
+
+  /* Parse the command line */
+
+  parse_args(&wdog, argc, argv);
+
+  /* Initialization of the WATCHDOG hardware is performed by logic external to
+   * this test.
+   */
+
+  ret = watchdog_devinit();
+  if (ret != OK)
+    {
+      message("wdog_main: watchdog_devinit failed: %d\n", ret);
+      goto errout;
+    }
+
+  /* Open the watchdog device for reading */
+
+  fd = open(CONFIG_EXAMPLES_WATCHDOG_DEVPATH, O_RDONLY);
+  if (fd < 0)
+    {
+      message("wdog_main: open %s failed: %d\n",
+              CONFIG_EXAMPLES_WATCHDOG_DEVPATH, errno);
+      goto errout;
+    }
+  message("wdog_main: starting output with frequency: %d duty: %08x count: %d\n",
+          info.frequency, info.duty, info.count);
+
+  /* Set the watchdog timeout */
+
+  ret = ioctl(fd, WDIOC_SETTIMEOUT, (unsigned long)wdog.timeout);
+  if (ret < 0)
+    {
+      message("wdog_main: ioctl(WDIOC_SETTIMEOUT) failed: %d\n", errno);
+      goto errout_with_dev;
+    }
+
+  /* Then start the watchdog timer. */
+
+  ret = ioctl(fd, WDIOC_START, 0);
+  if (ret < 0)
+    {
+      message("wdog_main: ioctl(WDIOC_START) failed: %d\n", errno);
+      goto errout_with_dev;
+    }
+
+  /* Then ping */
+
+  for (elapsed = 0; elapsed < wdog.pingtime; elapsed += wdog.pingdelay)
+    {
+      /* Sleep for the requested amount of time */
+
+      usleep(wdog.pingdelay * 1000);
+
+      /* Then ping */
+
+     ret = ioctl(fd, WDIOC_KEEPALIVE, 0);
+     if (ret < 0)
+       {
+          message("wdog_main: ioctl(WDIOC_KEEPALIVE) failed: %d\n", errno);
+          goto errout_with_dev;
+        }
+
+      message("  ping elapsed=%d\n", elpased);
+      msgflush();
+    }
+
+  /* Then stop pinging */
+
+  for (; ; elapsed += wdog.pingdelay)
+    {
+      /* Sleep for the requested amount of time */
+
+      usleep(wdog.pingdelay * 1000);
+
+      message("  NO ping elapsed=%d\n", elpased);
+      msgflush();
+    }
+
+  /* We should not get here */
+
+  ret = ioctl(fd, WDIOC_STOP, 0);
+  if (ret < 0)
+    {
+      message("wdog_main: ioctl(WDIOC_STOP) failed: %d\n", errno);
+      goto errout_with_dev;
+    }
+
+ close(fd);
+ msgflush();
+ return OK;
+
+errout_with_dev:
+  close(fd);
+errout:
+  msgflush();
+  return ERROR;
+}