Re: [PATCH 37/57] docs: watchdog: convert documents to ReST format

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On Mon, Apr 15, 2019 at 11:56:02PM -0300, Mauro Carvalho Chehab wrote:
> Convert those documents and prepare them to be part of the kernel
> API book, as most of the stuff there are related to the
> Kernel interfaces.
> 
> Still, in the future, it would make sense to split the docs,
> as some of the stuff is clearly focused on sysadmin tasks.
> 
> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

What is the plan here ? Submit through watchdog subsystem or through
some other subsystem ? Also, will the files be renamed ?

Thanks,
Guenter

> ---
>  .../convert_drivers_to_kernel_api.txt         | 109 +--
>  Documentation/watchdog/hpwdt.txt              |  23 +-
>  Documentation/watchdog/mlx-wdt.txt            |  24 +-
>  Documentation/watchdog/pcwd-watchdog.txt      |  13 +-
>  Documentation/watchdog/watchdog-api.txt       |  76 +-
>  .../watchdog/watchdog-kernel-api.txt          |  89 ++-
>  .../watchdog/watchdog-parameters.txt          | 672 +++++++++++++-----
>  Documentation/watchdog/watchdog-pm.txt        |   3 +
>  Documentation/watchdog/wdt.txt                |  31 +-
>  9 files changed, 733 insertions(+), 307 deletions(-)
> 
> diff --git a/Documentation/watchdog/convert_drivers_to_kernel_api.txt b/Documentation/watchdog/convert_drivers_to_kernel_api.txt
> index 9fffb2958d13..dd934cc08e40 100644
> --- a/Documentation/watchdog/convert_drivers_to_kernel_api.txt
> +++ b/Documentation/watchdog/convert_drivers_to_kernel_api.txt
> @@ -1,6 +1,8 @@
> +=========================================================
>  Converting old watchdog drivers to the watchdog framework
> +=========================================================
> +
>  by Wolfram Sang <w.sang@xxxxxxxxxxxxxx>
> -=========================================================
>  
>  Before the watchdog framework came into the kernel, every driver had to
>  implement the API on its own. Now, as the framework factored out the common
> @@ -69,16 +71,16 @@ Here is a overview of the functions and probably needed actions:
>    -ENOIOCTLCMD, the IOCTLs of the framework will be tried, too. Any other error
>    is directly given to the user.
>  
> -Example conversion:
> +Example conversion::
>  
> --static const struct file_operations s3c2410wdt_fops = {
> --       .owner          = THIS_MODULE,
> --       .llseek         = no_llseek,
> --       .write          = s3c2410wdt_write,
> --       .unlocked_ioctl = s3c2410wdt_ioctl,
> --       .open           = s3c2410wdt_open,
> --       .release        = s3c2410wdt_release,
> --};
> +  -static const struct file_operations s3c2410wdt_fops = {
> +  -       .owner          = THIS_MODULE,
> +  -       .llseek         = no_llseek,
> +  -       .write          = s3c2410wdt_write,
> +  -       .unlocked_ioctl = s3c2410wdt_ioctl,
> +  -       .open           = s3c2410wdt_open,
> +  -       .release        = s3c2410wdt_release,
> +  -};
>  
>  Check the functions for device-specific stuff and keep it for later
>  refactoring. The rest can go.
> @@ -89,24 +91,24 @@ Remove the miscdevice
>  
>  Since the file_operations are gone now, you can also remove the 'struct
>  miscdevice'. The framework will create it on watchdog_dev_register() called by
> -watchdog_register_device().
> +watchdog_register_device()::
>  
> --static struct miscdevice s3c2410wdt_miscdev = {
> --       .minor          = WATCHDOG_MINOR,
> --       .name           = "watchdog",
> --       .fops           = &s3c2410wdt_fops,
> --};
> +  -static struct miscdevice s3c2410wdt_miscdev = {
> +  -       .minor          = WATCHDOG_MINOR,
> +  -       .name           = "watchdog",
> +  -       .fops           = &s3c2410wdt_fops,
> +  -};
>  
>  
>  Remove obsolete includes and defines
>  ------------------------------------
>  
>  Because of the simplifications, a few defines are probably unused now. Remove
> -them. Includes can be removed, too. For example:
> +them. Includes can be removed, too. For example::
>  
> -- #include <linux/fs.h>
> -- #include <linux/miscdevice.h> (if MODULE_ALIAS_MISCDEV is not used)
> -- #include <linux/uaccess.h> (if no custom IOCTLs are used)
> +  - #include <linux/fs.h>
> +  - #include <linux/miscdevice.h> (if MODULE_ALIAS_MISCDEV is not used)
> +  - #include <linux/uaccess.h> (if no custom IOCTLs are used)
>  
>  
>  Add the watchdog operations
> @@ -121,30 +123,30 @@ change the function header. Other changes are most likely not needed, because
>  here simply happens the direct hardware access. If you have device-specific
>  code left from the above steps, it should be refactored into these callbacks.
>  
> -Here is a simple example:
> +Here is a simple example::
>  
> -+static struct watchdog_ops s3c2410wdt_ops = {
> -+       .owner = THIS_MODULE,
> -+       .start = s3c2410wdt_start,
> -+       .stop = s3c2410wdt_stop,
> -+       .ping = s3c2410wdt_keepalive,
> -+       .set_timeout = s3c2410wdt_set_heartbeat,
> -+};
> +  +static struct watchdog_ops s3c2410wdt_ops = {
> +  +       .owner = THIS_MODULE,
> +  +       .start = s3c2410wdt_start,
> +  +       .stop = s3c2410wdt_stop,
> +  +       .ping = s3c2410wdt_keepalive,
> +  +       .set_timeout = s3c2410wdt_set_heartbeat,
> +  +};
>  
> -A typical function-header change looks like:
> +A typical function-header change looks like::
>  
> --static void s3c2410wdt_keepalive(void)
> -+static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
> - {
> -...
> -+
> -+       return 0;
> - }
> +  -static void s3c2410wdt_keepalive(void)
> +  +static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
> +   {
> +  ...
> +  +
> +  +       return 0;
> +   }
>  
> -...
> +  ...
>  
> --       s3c2410wdt_keepalive();
> -+       s3c2410wdt_keepalive(&s3c2410_wdd);
> +  -       s3c2410wdt_keepalive();
> +  +       s3c2410wdt_keepalive(&s3c2410_wdd);
>  
>  
>  Add the watchdog device
> @@ -159,12 +161,12 @@ static variables. Those have to be converted to use the members in
>  watchdog_device. Note that the timeout values are unsigned int. Some drivers
>  use signed int, so this has to be converted, too.
>  
> -Here is a simple example for a watchdog device:
> +Here is a simple example for a watchdog device::
>  
> -+static struct watchdog_device s3c2410_wdd = {
> -+       .info = &s3c2410_wdt_ident,
> -+       .ops = &s3c2410wdt_ops,
> -+};
> +  +static struct watchdog_device s3c2410_wdd = {
> +  +       .info = &s3c2410_wdt_ident,
> +  +       .ops = &s3c2410wdt_ops,
> +  +};
>  
>  
>  Handle the 'nowayout' feature
> @@ -173,12 +175,12 @@ Handle the 'nowayout' feature
>  A few drivers use nowayout statically, i.e. there is no module parameter for it
>  and only CONFIG_WATCHDOG_NOWAYOUT determines if the feature is going to be
>  used. This needs to be converted by initializing the status variable of the
> -watchdog_device like this:
> +watchdog_device like this::
>  
>          .status = WATCHDOG_NOWAYOUT_INIT_STATUS,
>  
>  Most drivers, however, also allow runtime configuration of nowayout, usually
> -by adding a module parameter. The conversion for this would be something like:
> +by adding a module parameter. The conversion for this would be something like::
>  
>  	watchdog_set_nowayout(&s3c2410_wdd, nowayout);
>  
> @@ -191,15 +193,15 @@ Register the watchdog device
>  
>  Replace misc_register(&miscdev) with watchdog_register_device(&watchdog_dev).
>  Make sure the return value gets checked and the error message, if present,
> -still fits. Also convert the unregister case.
> +still fits. Also convert the unregister case::
>  
> --       ret = misc_register(&s3c2410wdt_miscdev);
> -+       ret = watchdog_register_device(&s3c2410_wdd);
> +  -       ret = misc_register(&s3c2410wdt_miscdev);
> +  +       ret = watchdog_register_device(&s3c2410_wdd);
>  
> -...
> +  ...
>  
> --       misc_deregister(&s3c2410wdt_miscdev);
> -+       watchdog_unregister_device(&s3c2410_wdd);
> +  -       misc_deregister(&s3c2410wdt_miscdev);
> +  +       watchdog_unregister_device(&s3c2410_wdd);
>  
>  
>  Update the Kconfig-entry
> @@ -207,7 +209,7 @@ Update the Kconfig-entry
>  
>  The entry for the driver now needs to select WATCHDOG_CORE:
>  
> -+       select WATCHDOG_CORE
> +  +       select WATCHDOG_CORE
>  
>  
>  Create a patch and send it to upstream
> @@ -215,4 +217,3 @@ Create a patch and send it to upstream
>  
>  Make sure you understood Documentation/process/submitting-patches.rst and send your patch to
>  linux-watchdog@xxxxxxxxxxxxxxx. We are looking forward to it :)
> -
> diff --git a/Documentation/watchdog/hpwdt.txt b/Documentation/watchdog/hpwdt.txt
> index 55df692c5595..a8c6751321de 100644
> --- a/Documentation/watchdog/hpwdt.txt
> +++ b/Documentation/watchdog/hpwdt.txt
> @@ -1,7 +1,12 @@
> +===========================
> +HPE iLO NMI Watchdog Driver
> +===========================
> +
> +for iLO based ProLiant Servers
> +==============================
> +
>  Last reviewed: 08/20/2018
>  
> -                     HPE iLO NMI Watchdog Driver
> -                   for iLO based ProLiant Servers
>  
>   The HPE iLO NMI Watchdog driver is a kernel module that provides basic
>   watchdog functionality and handler for the iLO "Generate NMI to System"
> @@ -20,21 +25,24 @@ Last reviewed: 08/20/2018
>  
>   The hpwdt driver also has the following module parameters:
>  
> - soft_margin - allows the user to set the watchdog timer value.
> + ============  ================================================================
> + soft_margin   allows the user to set the watchdog timer value.
>                 Default value is 30 seconds.
> - timeout     - an alias of soft_margin.
> - pretimeout  - allows the user to set the watchdog pretimeout value.
> + timeout       an alias of soft_margin.
> + pretimeout    allows the user to set the watchdog pretimeout value.
>                 This is the number of seconds before timeout when an
>                 NMI is delivered to the system. Setting the value to
>                 zero disables the pretimeout NMI.
>                 Default value is 9 seconds.
> - nowayout    - basic watchdog parameter that does not allow the timer to
> + nowayout      basic watchdog parameter that does not allow the timer to
>                 be restarted or an impending ASR to be escaped.
>                 Default value is set when compiling the kernel. If it is set
>                 to "Y", then there is no way of disabling the watchdog once
>                 it has been started.
> + ============  ================================================================
>  
> - NOTE: More information about watchdog drivers in general, including the ioctl
> + NOTE:
> +       More information about watchdog drivers in general, including the ioctl
>         interface to /dev/watchdog can be found in
>         Documentation/watchdog/watchdog-api.txt and Documentation/IPMI.txt.
>  
> @@ -63,4 +71,3 @@ Last reviewed: 08/20/2018
>  
>   The HPE iLO NMI Watchdog Driver and documentation were originally developed
>   by Tom Mingarelli.
> -
> diff --git a/Documentation/watchdog/mlx-wdt.txt b/Documentation/watchdog/mlx-wdt.txt
> index 66eeb78505c3..bf5bafac47f0 100644
> --- a/Documentation/watchdog/mlx-wdt.txt
> +++ b/Documentation/watchdog/mlx-wdt.txt
> @@ -1,5 +1,9 @@
> -		Mellanox watchdog drivers
> -		for x86 based system switches
> +=========================
> +Mellanox watchdog drivers
> +=========================
> +
> +for x86 based system switches
> +=============================
>  
>  This driver provides watchdog functionality for various Mellanox
>  Ethernet and Infiniband switch systems.
> @@ -9,16 +13,16 @@ Mellanox watchdog device is implemented in a programmable logic device.
>  There are 2 types of HW watchdog implementations.
>  
>  Type 1:
> -Actual HW timeout can be defined as a power of 2 msec.
> -e.g. timeout 20 sec will be rounded up to 32768 msec.
> -The maximum timeout period is 32 sec (32768 msec.),
> -Get time-left isn't supported
> +  Actual HW timeout can be defined as a power of 2 msec.
> +  e.g. timeout 20 sec will be rounded up to 32768 msec.
> +  The maximum timeout period is 32 sec (32768 msec.),
> +  Get time-left isn't supported
>  
>  Type 2:
> -Actual HW timeout is defined in sec. and it's the same as
> -a user-defined timeout.
> -Maximum timeout is 255 sec.
> -Get time-left is supported.
> +  Actual HW timeout is defined in sec. and it's the same as
> +  a user-defined timeout.
> +  Maximum timeout is 255 sec.
> +  Get time-left is supported.
>  
>  Type 1 HW watchdog implementation exist in old systems and
>  all new systems have type 2 HW watchdog.
> diff --git a/Documentation/watchdog/pcwd-watchdog.txt b/Documentation/watchdog/pcwd-watchdog.txt
> index b8e60a441a43..405e2a370082 100644
> --- a/Documentation/watchdog/pcwd-watchdog.txt
> +++ b/Documentation/watchdog/pcwd-watchdog.txt
> @@ -1,8 +1,13 @@
> +===================================
> +Berkshire Products PC Watchdog Card
> +===================================
> +
>  Last reviewed: 10/05/2007
>  
> -                     Berkshire Products PC Watchdog Card
> -                   Support for ISA Cards  Revision A and C
> -           Documentation and Driver by Ken Hollis <kenji@xxxxxxxxxxx>
> +Support for ISA Cards  Revision A and C
> +=======================================
> +
> +Documentation and Driver by Ken Hollis <kenji@xxxxxxxxxxx>
>  
>   The PC Watchdog is a card that offers the same type of functionality that
>   the WDT card does, only it doesn't require an IRQ to run.  Furthermore,
> @@ -33,6 +38,7 @@ Last reviewed: 10/05/2007
>  	WDIOC_GETSUPPORT
>  		This returns the support of the card itself.  This
>  		returns in structure "PCWDS" which returns:
> +
>  			options = WDIOS_TEMPPANIC
>  				  (This card supports temperature)
>  			firmware_version = xxxx
> @@ -63,4 +69,3 @@ Last reviewed: 10/05/2007
>  
>   -- Ken Hollis
>      (kenji@xxxxxxxxxxx)
> -
> diff --git a/Documentation/watchdog/watchdog-api.txt b/Documentation/watchdog/watchdog-api.txt
> index 0e62ba33b7fb..c6c1e9fa9f73 100644
> --- a/Documentation/watchdog/watchdog-api.txt
> +++ b/Documentation/watchdog/watchdog-api.txt
> @@ -1,7 +1,10 @@
> +=============================
> +The Linux Watchdog driver API
> +=============================
> +
>  Last reviewed: 10/05/2007
>  
>  
> -The Linux Watchdog driver API.
>  
>  Copyright 2002 Christer Weingel <wingel@xxxxxxxxxxxxxxx>
>  
> @@ -10,7 +13,8 @@ driver which is (c) Copyright 2000 Jakob Oestergaard <jakob@xxxxxxxxxxxx>
>  
>  This document describes the state of the Linux 2.4.18 kernel.
>  
> -Introduction:
> +Introduction
> +============
>  
>  A Watchdog Timer (WDT) is a hardware circuit that can reset the
>  computer system in case of a software fault.  You probably knew that
> @@ -30,7 +34,8 @@ drivers implement different, and sometimes incompatible, parts of it.
>  This file is an attempt to document the existing usage and allow
>  future driver writers to use it as a reference.
>  
> -The simplest API:
> +The simplest API
> +================
>  
>  All drivers support the basic mode of operation, where the watchdog
>  activates as soon as /dev/watchdog is opened and will reboot unless
> @@ -54,7 +59,8 @@ after the timeout has passed. Watchdog devices also usually support
>  the nowayout module parameter so that this option can be controlled at
>  runtime.
>  
> -Magic Close feature:
> +Magic Close feature
> +===================
>  
>  If a driver supports "Magic Close", the driver will not disable the
>  watchdog unless a specific magic character 'V' has been sent to
> @@ -64,7 +70,8 @@ will assume that the daemon (and userspace in general) died, and will
>  stop pinging the watchdog without disabling it first.  This will then
>  cause a reboot if the watchdog is not re-opened in sufficient time.
>  
> -The ioctl API:
> +The ioctl API
> +=============
>  
>  All conforming drivers also support an ioctl API.
>  
> @@ -73,7 +80,7 @@ Pinging the watchdog using an ioctl:
>  All drivers that have an ioctl interface support at least one ioctl,
>  KEEPALIVE.  This ioctl does exactly the same thing as a write to the
>  watchdog device, so the main loop in the above program could be
> -replaced with:
> +replaced with::
>  
>  	while (1) {
>  		ioctl(fd, WDIOC_KEEPALIVE, 0);
> @@ -82,14 +89,15 @@ replaced with:
>  
>  the argument to the ioctl is ignored.
>  
> -Setting and getting the timeout:
> +Setting and getting the timeout
> +===============================
>  
>  For some drivers it is possible to modify the watchdog timeout on the
>  fly with the SETTIMEOUT ioctl, those drivers have the WDIOF_SETTIMEOUT
>  flag set in their option field.  The argument is an integer
>  representing the timeout in seconds.  The driver returns the real
>  timeout used in the same variable, and this timeout might differ from
> -the requested one due to limitation of the hardware.
> +the requested one due to limitation of the hardware::
>  
>      int timeout = 45;
>      ioctl(fd, WDIOC_SETTIMEOUT, &timeout);
> @@ -99,18 +107,19 @@ This example might actually print "The timeout was set to 60 seconds"
>  if the device has a granularity of minutes for its timeout.
>  
>  Starting with the Linux 2.4.18 kernel, it is possible to query the
> -current timeout using the GETTIMEOUT ioctl.
> +current timeout using the GETTIMEOUT ioctl::
>  
>      ioctl(fd, WDIOC_GETTIMEOUT, &timeout);
>      printf("The timeout was is %d seconds\n", timeout);
>  
> -Pretimeouts:
> +Pretimeouts
> +===========
>  
>  Some watchdog timers can be set to have a trigger go off before the
>  actual time they will reset the system.  This can be done with an NMI,
>  interrupt, or other mechanism.  This allows Linux to record useful
>  information (like panic information and kernel coredumps) before it
> -resets.
> +resets::
>  
>      pretimeout = 10;
>      ioctl(fd, WDIOC_SETPRETIMEOUT, &pretimeout);
> @@ -121,89 +130,113 @@ the pretimeout.  So, for instance, if you set the timeout to 60 seconds
>  and the pretimeout to 10 seconds, the pretimeout will go off in 50
>  seconds.  Setting a pretimeout to zero disables it.
>  
> -There is also a get function for getting the pretimeout:
> +There is also a get function for getting the pretimeout::
>  
>      ioctl(fd, WDIOC_GETPRETIMEOUT, &timeout);
>      printf("The pretimeout was is %d seconds\n", timeout);
>  
>  Not all watchdog drivers will support a pretimeout.
>  
> -Get the number of seconds before reboot:
> +Get the number of seconds before reboot
> +=======================================
>  
>  Some watchdog drivers have the ability to report the remaining time
>  before the system will reboot. The WDIOC_GETTIMELEFT is the ioctl
> -that returns the number of seconds before reboot.
> +that returns the number of seconds before reboot::
>  
>      ioctl(fd, WDIOC_GETTIMELEFT, &timeleft);
>      printf("The timeout was is %d seconds\n", timeleft);
>  
> -Environmental monitoring:
> +Environmental monitoring
> +========================
>  
>  All watchdog drivers are required return more information about the system,
>  some do temperature, fan and power level monitoring, some can tell you
>  the reason for the last reboot of the system.  The GETSUPPORT ioctl is
> -available to ask what the device can do:
> +available to ask what the device can do::
>  
>  	struct watchdog_info ident;
>  	ioctl(fd, WDIOC_GETSUPPORT, &ident);
>  
>  the fields returned in the ident struct are:
>  
> +	================	=============================================
>          identity		a string identifying the watchdog driver
>  	firmware_version	the firmware version of the card if available
>  	options			a flags describing what the device supports
> +	================	=============================================
>  
>  the options field can have the following bits set, and describes what
>  kind of information that the GET_STATUS and GET_BOOT_STATUS ioctls can
>  return.   [FIXME -- Is this correct?]
>  
> +	================	=========================
>  	WDIOF_OVERHEAT		Reset due to CPU overheat
> +	================	=========================
>  
>  The machine was last rebooted by the watchdog because the thermal limit was
> -exceeded
> +exceeded:
>  
> +	==============		==========
>  	WDIOF_FANFAULT		Fan failed
> +	==============		==========
>  
>  A system fan monitored by the watchdog card has failed
>  
> +	=============		================
>  	WDIOF_EXTERN1		External relay 1
> +	=============		================
>  
>  External monitoring relay/source 1 was triggered. Controllers intended for
>  real world applications include external monitoring pins that will trigger
>  a reset.
>  
> +	=============		================
>  	WDIOF_EXTERN2		External relay 2
> +	=============		================
>  
>  External monitoring relay/source 2 was triggered
>  
> +	================	=====================
>  	WDIOF_POWERUNDER	Power bad/power fault
> +	================	=====================
>  
>  The machine is showing an undervoltage status
>  
> +	===============		=============================
>  	WDIOF_CARDRESET		Card previously reset the CPU
> +	===============		=============================
>  
>  The last reboot was caused by the watchdog card
>  
> +	================	=====================
>  	WDIOF_POWEROVER		Power over voltage
> +	================	=====================
>  
>  The machine is showing an overvoltage status. Note that if one level is
>  under and one over both bits will be set - this may seem odd but makes
>  sense.
>  
> +	===================	=====================
>  	WDIOF_KEEPALIVEPING	Keep alive ping reply
> +	===================	=====================
>  
>  The watchdog saw a keepalive ping since it was last queried.
>  
> +	================	=======================
>  	WDIOF_SETTIMEOUT	Can set/get the timeout
> +	================	=======================
>  
>  The watchdog can do pretimeouts.
>  
> +	================	================================
>  	WDIOF_PRETIMEOUT	Pretimeout (in seconds), get/set
> +	================	================================
>  
>  
>  For those drivers that return any bits set in the option field, the
>  GETSTATUS and GETBOOTSTATUS ioctls can be used to ask for the current
> -status, and the status at the last reboot, respectively.  
> +status, and the status at the last reboot, respectively::
>  
>      int flags;
>      ioctl(fd, WDIOC_GETSTATUS, &flags);
> @@ -216,22 +249,23 @@ Note that not all devices support these two calls, and some only
>  support the GETBOOTSTATUS call.
>  
>  Some drivers can measure the temperature using the GETTEMP ioctl.  The
> -returned value is the temperature in degrees fahrenheit.
> +returned value is the temperature in degrees fahrenheit::
>  
>      int temperature;
>      ioctl(fd, WDIOC_GETTEMP, &temperature);
>  
>  Finally the SETOPTIONS ioctl can be used to control some aspects of
> -the cards operation.
> +the cards operation::
>  
>      int options = 0;
>      ioctl(fd, WDIOC_SETOPTIONS, &options);
>  
>  The following options are available:
>  
> +	=================	================================
>  	WDIOS_DISABLECARD	Turn off the watchdog timer
>  	WDIOS_ENABLECARD	Turn on the watchdog timer
>  	WDIOS_TEMPPANIC		Kernel panic on temperature trip
> +	=================	================================
>  
>  [FIXME -- better explanations]
> -
> diff --git a/Documentation/watchdog/watchdog-kernel-api.txt b/Documentation/watchdog/watchdog-kernel-api.txt
> index 3a91ef5af044..452002be568c 100644
> --- a/Documentation/watchdog/watchdog-kernel-api.txt
> +++ b/Documentation/watchdog/watchdog-kernel-api.txt
> @@ -1,5 +1,7 @@
> -The Linux WatchDog Timer Driver Core kernel API.
>  ===============================================
> +The Linux WatchDog Timer Driver Core kernel API
> +===============================================
> +
>  Last reviewed: 12-Feb-2013
>  
>  Wim Van Sebroeck <wim@xxxxxxxxx>
> @@ -23,10 +25,10 @@ The API
>  Each watchdog timer driver that wants to use the WatchDog Timer Driver Core
>  must #include <linux/watchdog.h> (you would have to do this anyway when
>  writing a watchdog device driver). This include file contains following
> -register/unregister routines:
> +register/unregister routines::
>  
> -extern int watchdog_register_device(struct watchdog_device *);
> -extern void watchdog_unregister_device(struct watchdog_device *);
> +	extern int watchdog_register_device(struct watchdog_device *);
> +	extern void watchdog_unregister_device(struct watchdog_device *);
>  
>  The watchdog_register_device routine registers a watchdog timer device.
>  The parameter of this routine is a pointer to a watchdog_device structure.
> @@ -40,9 +42,9 @@ The watchdog subsystem includes an registration deferral mechanism,
>  which allows you to register an watchdog as early as you wish during
>  the boot process.
>  
> -The watchdog device structure looks like this:
> +The watchdog device structure looks like this::
>  
> -struct watchdog_device {
> +  struct watchdog_device {
>  	int id;
>  	struct device *parent;
>  	const struct attribute_group **groups;
> @@ -62,9 +64,10 @@ struct watchdog_device {
>  	struct watchdog_core_data *wd_data;
>  	unsigned long status;
>  	struct list_head deferred;
> -};
> +  };
>  
>  It contains following fields:
> +
>  * id: set by watchdog_register_device, id 0 is special. It has both a
>    /dev/watchdog0 cdev (dynamic major, minor 0) as well as the old
>    /dev/watchdog miscdev. The id is set automatically when calling
> @@ -114,9 +117,9 @@ It contains following fields:
>  * deferred: entry in wtd_deferred_reg_list which is used to
>    register early initialized watchdogs.
>  
> -The list of watchdog operations is defined as:
> +The list of watchdog operations is defined as::
>  
> -struct watchdog_ops {
> +  struct watchdog_ops {
>  	struct module *owner;
>  	/* mandatory operations */
>  	int (*start)(struct watchdog_device *);
> @@ -129,7 +132,7 @@ struct watchdog_ops {
>  	unsigned int (*get_timeleft)(struct watchdog_device *);
>  	int (*restart)(struct watchdog_device *);
>  	long (*ioctl)(struct watchdog_device *, unsigned int, unsigned long);
> -};
> +  };
>  
>  It is important that you first define the module owner of the watchdog timer
>  driver's operations. This module owner will be used to lock the module when
> @@ -138,6 +141,7 @@ module and /dev/watchdog is still open).
>  
>  Some operations are mandatory and some are optional. The mandatory operations
>  are:
> +
>  * start: this is a pointer to the routine that starts the watchdog timer
>    device.
>    The routine needs a pointer to the watchdog timer device structure as a
> @@ -146,51 +150,64 @@ are:
>  Not all watchdog timer hardware supports the same functionality. That's why
>  all other routines/operations are optional. They only need to be provided if
>  they are supported. These optional routines/operations are:
> +
>  * stop: with this routine the watchdog timer device is being stopped.
> +
>    The routine needs a pointer to the watchdog timer device structure as a
>    parameter. It returns zero on success or a negative errno code for failure.
>    Some watchdog timer hardware can only be started and not be stopped. A
>    driver supporting such hardware does not have to implement the stop routine.
> +
>    If a driver has no stop function, the watchdog core will set WDOG_HW_RUNNING
>    and start calling the driver's keepalive pings function after the watchdog
>    device is closed.
> +
>    If a watchdog driver does not implement the stop function, it must set
>    max_hw_heartbeat_ms.
>  * ping: this is the routine that sends a keepalive ping to the watchdog timer
>    hardware.
> +
>    The routine needs a pointer to the watchdog timer device structure as a
>    parameter. It returns zero on success or a negative errno code for failure.
> +
>    Most hardware that does not support this as a separate function uses the
>    start function to restart the watchdog timer hardware. And that's also what
>    the watchdog timer driver core does: to send a keepalive ping to the watchdog
>    timer hardware it will either use the ping operation (when available) or the
>    start operation (when the ping operation is not available).
> +
>    (Note: the WDIOC_KEEPALIVE ioctl call will only be active when the
>    WDIOF_KEEPALIVEPING bit has been set in the option field on the watchdog's
>    info structure).
>  * status: this routine checks the status of the watchdog timer device. The
>    status of the device is reported with watchdog WDIOF_* status flags/bits.
> +
>    WDIOF_MAGICCLOSE and WDIOF_KEEPALIVEPING are reported by the watchdog core;
>    it is not necessary to report those bits from the driver. Also, if no status
>    function is provided by the driver, the watchdog core reports the status bits
>    provided in the bootstatus variable of struct watchdog_device.
> +
>  * set_timeout: this routine checks and changes the timeout of the watchdog
>    timer device. It returns 0 on success, -EINVAL for "parameter out of range"
>    and -EIO for "could not write value to the watchdog". On success this
>    routine should set the timeout value of the watchdog_device to the
>    achieved timeout value (which may be different from the requested one
>    because the watchdog does not necessarily have a 1 second resolution).
> +
>    Drivers implementing max_hw_heartbeat_ms set the hardware watchdog heartbeat
>    to the minimum of timeout and max_hw_heartbeat_ms. Those drivers set the
>    timeout value of the watchdog_device either to the requested timeout value
>    (if it is larger than max_hw_heartbeat_ms), or to the achieved timeout value.
>    (Note: the WDIOF_SETTIMEOUT needs to be set in the options field of the
>    watchdog's info structure).
> +
>    If the watchdog driver does not have to perform any action but setting the
>    watchdog_device.timeout, this callback can be omitted.
> +
>    If set_timeout is not provided but, WDIOF_SETTIMEOUT is set, the watchdog
>    infrastructure updates the timeout value of the watchdog_device internally
>    to the requested value.
> +
>    If the pretimeout feature is used (WDIOF_PRETIMEOUT), then set_timeout must
>    also take care of checking if pretimeout is still valid and set up the timer
>    accordingly. This can't be done in the core without races, so it is the
> @@ -201,13 +218,16 @@ they are supported. These optional routines/operations are:
>    seconds before the actual timeout would happen. It returns 0 on success,
>    -EINVAL for "parameter out of range" and -EIO for "could not write value to
>    the watchdog". A value of 0 disables pretimeout notification.
> +
>    (Note: the WDIOF_PRETIMEOUT needs to be set in the options field of the
>    watchdog's info structure).
> +
>    If the watchdog driver does not have to perform any action but setting the
>    watchdog_device.pretimeout, this callback can be omitted. That means if
>    set_pretimeout is not provided but WDIOF_PRETIMEOUT is set, the watchdog
>    infrastructure updates the pretimeout value of the watchdog_device internally
>    to the requested value.
> +
>  * get_timeleft: this routines returns the time that's left before a reset.
>  * restart: this routine restarts the machine. It returns 0 on success or a
>    negative errno code for failure.
> @@ -218,6 +238,7 @@ they are supported. These optional routines/operations are:
>  
>  The status bits should (preferably) be set with the set_bit and clear_bit alike
>  bit-operations. The status bits that are defined are:
> +
>  * WDOG_ACTIVE: this status bit indicates whether or not a watchdog timer device
>    is active or not from user perspective. User space is expected to send
>    heartbeat requests to the driver while this flag is set.
> @@ -235,22 +256,30 @@ bit-operations. The status bits that are defined are:
>  
>    To set the WDOG_NO_WAY_OUT status bit (before registering your watchdog
>    timer device) you can either:
> +
>    * set it statically in your watchdog_device struct with
> +
>  	.status = WATCHDOG_NOWAYOUT_INIT_STATUS,
> +
>      (this will set the value the same as CONFIG_WATCHDOG_NOWAYOUT) or
> -  * use the following helper function:
> -  static inline void watchdog_set_nowayout(struct watchdog_device *wdd, int nowayout)
> +  * use the following helper function::
> +
> +	static inline void watchdog_set_nowayout(struct watchdog_device *wdd,
> +						 int nowayout)
> +
> +Note:
> +   The WatchDog Timer Driver Core supports the magic close feature and
> +   the nowayout feature. To use the magic close feature you must set the
> +   WDIOF_MAGICCLOSE bit in the options field of the watchdog's info structure.
>  
> -Note: The WatchDog Timer Driver Core supports the magic close feature and
> -the nowayout feature. To use the magic close feature you must set the
> -WDIOF_MAGICCLOSE bit in the options field of the watchdog's info structure.
>  The nowayout feature will overrule the magic close feature.
>  
>  To get or set driver specific data the following two helper functions should be
> -used:
> +used::
>  
> -static inline void watchdog_set_drvdata(struct watchdog_device *wdd, void *data)
> -static inline void *watchdog_get_drvdata(struct watchdog_device *wdd)
> +  static inline void watchdog_set_drvdata(struct watchdog_device *wdd,
> +					  void *data)
> +  static inline void *watchdog_get_drvdata(struct watchdog_device *wdd)
>  
>  The watchdog_set_drvdata function allows you to add driver specific data. The
>  arguments of this function are the watchdog device where you want to add the
> @@ -260,10 +289,11 @@ The watchdog_get_drvdata function allows you to retrieve driver specific data.
>  The argument of this function is the watchdog device where you want to retrieve
>  data from. The function returns the pointer to the driver specific data.
>  
> -To initialize the timeout field, the following function can be used:
> +To initialize the timeout field, the following function can be used::
>  
> -extern int watchdog_init_timeout(struct watchdog_device *wdd,
> -                                  unsigned int timeout_parm, struct device *dev);
> +  extern int watchdog_init_timeout(struct watchdog_device *wdd,
> +                                   unsigned int timeout_parm,
> +                                   struct device *dev);
>  
>  The watchdog_init_timeout function allows you to initialize the timeout field
>  using the module timeout parameter or by retrieving the timeout-sec property from
> @@ -272,30 +302,33 @@ to set the default timeout value as timeout value in the watchdog_device and
>  then use this function to set the user "preferred" timeout value.
>  This routine returns zero on success and a negative errno code for failure.
>  
> -To disable the watchdog on reboot, the user must call the following helper:
> +To disable the watchdog on reboot, the user must call the following helper::
>  
> -static inline void watchdog_stop_on_reboot(struct watchdog_device *wdd);
> +  static inline void watchdog_stop_on_reboot(struct watchdog_device *wdd);
>  
>  To disable the watchdog when unregistering the watchdog, the user must call
>  the following helper. Note that this will only stop the watchdog if the
>  nowayout flag is not set.
>  
> -static inline void watchdog_stop_on_unregister(struct watchdog_device *wdd);
> +::
> +
> +  static inline void watchdog_stop_on_unregister(struct watchdog_device *wdd);
>  
>  To change the priority of the restart handler the following helper should be
> -used:
> +used::
>  
> -void watchdog_set_restart_priority(struct watchdog_device *wdd, int priority);
> +  void watchdog_set_restart_priority(struct watchdog_device *wdd, int priority);
>  
>  User should follow the following guidelines for setting the priority:
> +
>  * 0: should be called in last resort, has limited restart capabilities
>  * 128: default restart handler, use if no other handler is expected to be
>    available, and/or if restart is sufficient to restart the entire system
>  * 255: highest priority, will preempt all other restart handlers
>  
> -To raise a pretimeout notification, the following function should be used:
> +To raise a pretimeout notification, the following function should be used::
>  
> -void watchdog_notify_pretimeout(struct watchdog_device *wdd)
> +  void watchdog_notify_pretimeout(struct watchdog_device *wdd)
>  
>  The function can be called in the interrupt context. If watchdog pretimeout
>  governor framework (kbuild CONFIG_WATCHDOG_PRETIMEOUT_GOV symbol) is enabled,
> diff --git a/Documentation/watchdog/watchdog-parameters.txt b/Documentation/watchdog/watchdog-parameters.txt
> index 0b88e333f9e1..b121caae7798 100644
> --- a/Documentation/watchdog/watchdog-parameters.txt
> +++ b/Documentation/watchdog/watchdog-parameters.txt
> @@ -1,410 +1,736 @@
> +==========================
> +WatchDog Module Parameters
> +==========================
> +
>  This file provides information on the module parameters of many of
>  the Linux watchdog drivers.  Watchdog driver parameter specs should
>  be listed here unless the driver has its own driver-specific information
>  file.
>  
> -
>  See Documentation/admin-guide/kernel-parameters.rst for information on
>  providing kernel parameters for builtin drivers versus loadable
>  modules.
>  
> -
>  -------------------------------------------------
> +
>  acquirewdt:
> -wdt_stop: Acquire WDT 'stop' io port (default 0x43)
> -wdt_start: Acquire WDT 'start' io port (default 0x443)
> -nowayout: Watchdog cannot be stopped once started
> +    wdt_stop:
> +	Acquire WDT 'stop' io port (default 0x43)
> +    wdt_start:
> +	Acquire WDT 'start' io port (default 0x443)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  advantechwdt:
> -wdt_stop: Advantech WDT 'stop' io port (default 0x443)
> -wdt_start: Advantech WDT 'start' io port (default 0x443)
> -timeout: Watchdog timeout in seconds. 1<= timeout <=63, default=60.
> -nowayout: Watchdog cannot be stopped once started
> +    wdt_stop:
> +	Advantech WDT 'stop' io port (default 0x443)
> +    wdt_start:
> +	Advantech WDT 'start' io port (default 0x443)
> +    timeout:
> +	Watchdog timeout in seconds. 1<= timeout <=63, default=60.
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  alim1535_wdt:
> -timeout: Watchdog timeout in seconds. (0 < timeout < 18000, default=60
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds. (0 < timeout < 18000, default=60
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  alim7101_wdt:
> -timeout: Watchdog timeout in seconds. (1<=timeout<=3600, default=30
> -use_gpio: Use the gpio watchdog (required by old cobalt boards).
> +    timeout:
> +	Watchdog timeout in seconds. (1<=timeout<=3600, default=30
> +    use_gpio:
> +	Use the gpio watchdog (required by old cobalt boards).
>  	default=0/off/no
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  ar7_wdt:
> -margin: Watchdog margin in seconds (default=60)
> -nowayout: Disable watchdog shutdown on close
> +    margin:
> +	Watchdog margin in seconds (default=60)
> +    nowayout:
> +	Disable watchdog shutdown on close
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  armada_37xx_wdt:
> -timeout: Watchdog timeout in seconds. (default=120)
> -nowayout: Disable watchdog shutdown on close
> +    timeout:
> +	Watchdog timeout in seconds. (default=120)
> +    nowayout:
> +	Disable watchdog shutdown on close
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  at91rm9200_wdt:
> -wdt_time: Watchdog time in seconds. (default=5)
> -nowayout: Watchdog cannot be stopped once started
> +    wdt_time:
> +	Watchdog time in seconds. (default=5)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  at91sam9_wdt:
> -heartbeat: Watchdog heartbeats in seconds. (default = 15)
> -nowayout: Watchdog cannot be stopped once started
> +    heartbeat:
> +	Watchdog heartbeats in seconds. (default = 15)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  bcm47xx_wdt:
> -wdt_time: Watchdog time in seconds. (default=30)
> -nowayout: Watchdog cannot be stopped once started
> +    wdt_time:
> +	Watchdog time in seconds. (default=30)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  coh901327_wdt:
> -margin: Watchdog margin in seconds (default 60s)
> +    margin:
> +	Watchdog margin in seconds (default 60s)
> +
>  -------------------------------------------------
> +
>  cpu5wdt:
> -port: base address of watchdog card, default is 0x91
> -verbose: be verbose, default is 0 (no)
> -ticks: count down ticks, default is 10000
> +    port:
> +	base address of watchdog card, default is 0x91
> +    verbose:
> +	be verbose, default is 0 (no)
> +    ticks:
> +	count down ticks, default is 10000
> +
>  -------------------------------------------------
> +
>  cpwd:
> -wd0_timeout: Default watchdog0 timeout in 1/10secs
> -wd1_timeout: Default watchdog1 timeout in 1/10secs
> -wd2_timeout: Default watchdog2 timeout in 1/10secs
> +    wd0_timeout:
> +	Default watchdog0 timeout in 1/10secs
> +    wd1_timeout:
> +	Default watchdog1 timeout in 1/10secs
> +    wd2_timeout:
> +	Default watchdog2 timeout in 1/10secs
> +
>  -------------------------------------------------
> +
>  da9052wdt:
> -timeout: Watchdog timeout in seconds. 2<= timeout <=131, default=2.048s
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds. 2<= timeout <=131, default=2.048s
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  davinci_wdt:
> -heartbeat: Watchdog heartbeat period in seconds from 1 to 600, default 60
> +    heartbeat:
> +	Watchdog heartbeat period in seconds from 1 to 600, default 60
> +
>  -------------------------------------------------
> +
>  ebc-c384_wdt:
> -timeout: Watchdog timeout in seconds. (1<=timeout<=15300, default=60)
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds. (1<=timeout<=15300, default=60)
> +    nowayout:
> +	Watchdog cannot be stopped once started
> +
>  -------------------------------------------------
> +
>  ep93xx_wdt:
> -nowayout: Watchdog cannot be stopped once started
> -timeout: Watchdog timeout in seconds. (1<=timeout<=3600, default=TBD)
> +    nowayout:
> +	Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds. (1<=timeout<=3600, default=TBD)
> +
>  -------------------------------------------------
> +
>  eurotechwdt:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> -io: Eurotech WDT io port (default=0x3f0)
> -irq: Eurotech WDT irq (default=10)
> -ev: Eurotech WDT event type (default is `int')
> +    io:
> +	Eurotech WDT io port (default=0x3f0)
> +    irq:
> +	Eurotech WDT irq (default=10)
> +    ev:
> +	Eurotech WDT event type (default is `int`)
> +
>  -------------------------------------------------
> +
>  gef_wdt:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  geodewdt:
> -timeout: Watchdog timeout in seconds. 1<= timeout <=131, default=60.
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds. 1<= timeout <=131, default=60.
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  i6300esb:
> -heartbeat: Watchdog heartbeat in seconds. (1<heartbeat<2046, default=30)
> -nowayout: Watchdog cannot be stopped once started
> +    heartbeat:
> +	Watchdog heartbeat in seconds. (1<heartbeat<2046, default=30)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  iTCO_wdt:
> -heartbeat: Watchdog heartbeat in seconds.
> +    heartbeat:
> +	Watchdog heartbeat in seconds.
>  	(2<heartbeat<39 (TCO v1) or 613 (TCO v2), default=30)
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  iTCO_vendor_support:
> -vendorsupport: iTCO vendor specific support mode, default=0 (none),
> +    vendorsupport:
> +	iTCO vendor specific support mode, default=0 (none),
>  	1=SuperMicro Pent3, 2=SuperMicro Pent4+, 911=Broken SMI BIOS
> +
>  -------------------------------------------------
> +
>  ib700wdt:
> -timeout: Watchdog timeout in seconds. 0<= timeout <=30, default=30.
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds. 0<= timeout <=30, default=30.
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  ibmasr:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  imx2_wdt:
> -timeout: Watchdog timeout in seconds (default 60 s)
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds (default 60 s)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  indydog:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  iop_wdt:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  it8712f_wdt:
> -margin: Watchdog margin in seconds (default 60)
> -nowayout: Disable watchdog shutdown on close
> +    margin:
> +	Watchdog margin in seconds (default 60)
> +    nowayout:
> +	Disable watchdog shutdown on close
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  it87_wdt:
> -nogameport: Forbid the activation of game port, default=0
> -nocir: Forbid the use of CIR (workaround for some buggy setups); set to 1 if
> +    nogameport:
> +	Forbid the activation of game port, default=0
> +    nocir:
> +	Forbid the use of CIR (workaround for some buggy setups); set to 1 if
>  system resets despite watchdog daemon running, default=0
> -exclusive: Watchdog exclusive device open, default=1
> -timeout: Watchdog timeout in seconds, default=60
> -testmode: Watchdog test mode (1 = no reboot), default=0
> -nowayout: Watchdog cannot be stopped once started
> +    exclusive:
> +	Watchdog exclusive device open, default=1
> +    timeout:
> +	Watchdog timeout in seconds, default=60
> +    testmode:
> +	Watchdog test mode (1 = no reboot), default=0
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  ixp4xx_wdt:
> -heartbeat: Watchdog heartbeat in seconds (default 60s)
> -nowayout: Watchdog cannot be stopped once started
> +    heartbeat:
> +	Watchdog heartbeat in seconds (default 60s)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  ks8695_wdt:
> -wdt_time: Watchdog time in seconds. (default=5)
> -nowayout: Watchdog cannot be stopped once started
> +    wdt_time:
> +	Watchdog time in seconds. (default=5)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  machzwd:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> -action: after watchdog resets, generate:
> +    action:
> +	after watchdog resets, generate:
>  	0 = RESET(*)  1 = SMI  2 = NMI  3 = SCI
> +
>  -------------------------------------------------
> +
>  max63xx_wdt:
> -heartbeat: Watchdog heartbeat period in seconds from 1 to 60, default 60
> -nowayout: Watchdog cannot be stopped once started
> +    heartbeat:
> +	Watchdog heartbeat period in seconds from 1 to 60, default 60
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> -nodelay: Force selection of a timeout setting without initial delay
> +    nodelay:
> +	Force selection of a timeout setting without initial delay
>  	(max6373/74 only, default=0)
> +
>  -------------------------------------------------
> +
>  mixcomwd:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  mpc8xxx_wdt:
> -timeout: Watchdog timeout in ticks. (0<timeout<65536, default=65535)
> -reset: Watchdog Interrupt/Reset Mode. 0 = interrupt, 1 = reset
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in ticks. (0<timeout<65536, default=65535)
> +    reset:
> +	Watchdog Interrupt/Reset Mode. 0 = interrupt, 1 = reset
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  mv64x60_wdt:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  ni903x_wdt:
> -timeout: Initial watchdog timeout in seconds (0<timeout<516, default=60)
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Initial watchdog timeout in seconds (0<timeout<516, default=60)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  nic7018_wdt:
> -timeout: Initial watchdog timeout in seconds (0<timeout<464, default=80)
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Initial watchdog timeout in seconds (0<timeout<464, default=80)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  nuc900_wdt:
> -heartbeat: Watchdog heartbeats in seconds.
> +    heartbeat:
> +	Watchdog heartbeats in seconds.
>  	(default = 15)
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  omap_wdt:
> -timer_margin: initial watchdog timeout (in seconds)
> -early_enable: Watchdog is started on module insertion (default=0
> -nowayout: Watchdog cannot be stopped once started
> +    timer_margin:
> +	initial watchdog timeout (in seconds)
> +    early_enable:
> +	Watchdog is started on module insertion (default=0
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  orion_wdt:
> -heartbeat: Initial watchdog heartbeat in seconds
> -nowayout: Watchdog cannot be stopped once started
> +    heartbeat:
> +	Initial watchdog heartbeat in seconds
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  pc87413_wdt:
> -io: pc87413 WDT I/O port (default: io).
> -timeout: Watchdog timeout in minutes (default=timeout).
> -nowayout: Watchdog cannot be stopped once started
> +    io:
> +	pc87413 WDT I/O port (default: io).
> +    timeout:
> +	Watchdog timeout in minutes (default=timeout).
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  pika_wdt:
> -heartbeat: Watchdog heartbeats in seconds. (default = 15)
> -nowayout: Watchdog cannot be stopped once started
> +    heartbeat:
> +	Watchdog heartbeats in seconds. (default = 15)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  pnx4008_wdt:
> -heartbeat: Watchdog heartbeat period in seconds from 1 to 60, default 19
> -nowayout: Set to 1 to keep watchdog running after device release
> +    heartbeat:
> +	Watchdog heartbeat period in seconds from 1 to 60, default 19
> +    nowayout:
> +	Set to 1 to keep watchdog running after device release
> +
>  -------------------------------------------------
> +
>  pnx833x_wdt:
> -timeout: Watchdog timeout in Mhz. (68Mhz clock), default=2040000000 (30 seconds)
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in Mhz. (68Mhz clock), default=2040000000 (30 seconds)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> -start_enabled: Watchdog is started on module insertion (default=1)
> +    start_enabled:
> +	Watchdog is started on module insertion (default=1)
> +
>  -------------------------------------------------
> +
>  rc32434_wdt:
> -timeout: Watchdog timeout value, in seconds (default=20)
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout value, in seconds (default=20)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  riowd:
> -riowd_timeout: Watchdog timeout in minutes (default=1)
> +    riowd_timeout:
> +	Watchdog timeout in minutes (default=1)
> +
>  -------------------------------------------------
> +
>  s3c2410_wdt:
> -tmr_margin: Watchdog tmr_margin in seconds. (default=15)
> -tmr_atboot: Watchdog is started at boot time if set to 1, default=0
> -nowayout: Watchdog cannot be stopped once started
> +    tmr_margin:
> +	Watchdog tmr_margin in seconds. (default=15)
> +    tmr_atboot:
> +	Watchdog is started at boot time if set to 1, default=0
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> -soft_noboot: Watchdog action, set to 1 to ignore reboots, 0 to reboot
> -debug: Watchdog debug, set to >1 for debug, (default 0)
> +    soft_noboot:
> +	Watchdog action, set to 1 to ignore reboots, 0 to reboot
> +    debug:
> +	Watchdog debug, set to >1 for debug, (default 0)
> +
>  -------------------------------------------------
> +
>  sa1100_wdt:
> -margin: Watchdog margin in seconds (default 60s)
> +    margin:
> +	Watchdog margin in seconds (default 60s)
> +
>  -------------------------------------------------
> +
>  sb_wdog:
> -timeout: Watchdog timeout in microseconds (max/default 8388607 or 8.3ish secs)
> +    timeout:
> +	Watchdog timeout in microseconds (max/default 8388607 or 8.3ish secs)
> +
>  -------------------------------------------------
> +
>  sbc60xxwdt:
> -wdt_stop: SBC60xx WDT 'stop' io port (default 0x45)
> -wdt_start: SBC60xx WDT 'start' io port (default 0x443)
> -timeout: Watchdog timeout in seconds. (1<=timeout<=3600, default=30)
> -nowayout: Watchdog cannot be stopped once started
> +    wdt_stop:
> +	SBC60xx WDT 'stop' io port (default 0x45)
> +    wdt_start:
> +	SBC60xx WDT 'start' io port (default 0x443)
> +    timeout:
> +	Watchdog timeout in seconds. (1<=timeout<=3600, default=30)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  sbc7240_wdt:
> -timeout: Watchdog timeout in seconds. (1<=timeout<=255, default=30)
> -nowayout: Disable watchdog when closing device file
> +    timeout:
> +	Watchdog timeout in seconds. (1<=timeout<=255, default=30)
> +    nowayout:
> +	Disable watchdog when closing device file
> +
>  -------------------------------------------------
> +
>  sbc8360:
> -timeout: Index into timeout table (0-63) (default=27 (60s))
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Index into timeout table (0-63) (default=27 (60s))
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  sbc_epx_c3:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  sbc_fitpc2_wdt:
> -margin: Watchdog margin in seconds (default 60s)
> -nowayout: Watchdog cannot be stopped once started
> +    margin:
> +	Watchdog margin in seconds (default 60s)
> +    nowayout:
> +	Watchdog cannot be stopped once started
> +
>  -------------------------------------------------
> +
>  sbsa_gwdt:
> -timeout: Watchdog timeout in seconds. (default 10s)
> -action: Watchdog action at the first stage timeout,
> +    timeout:
> +	Watchdog timeout in seconds. (default 10s)
> +    action:
> +	Watchdog action at the first stage timeout,
>  	set to 0 to ignore, 1 to panic. (default=0)
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  sc1200wdt:
> -isapnp: When set to 0 driver ISA PnP support will be disabled (default=1)
> -io: io port
> -timeout: range is 0-255 minutes, default is 1
> -nowayout: Watchdog cannot be stopped once started
> +    isapnp:
> +	When set to 0 driver ISA PnP support will be disabled (default=1)
> +    io:
> +	io port
> +    timeout:
> +	range is 0-255 minutes, default is 1
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  sc520_wdt:
> -timeout: Watchdog timeout in seconds. (1 <= timeout <= 3600, default=30)
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds. (1 <= timeout <= 3600, default=30)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  sch311x_wdt:
> -force_id: Override the detected device ID
> -therm_trip: Should a ThermTrip trigger the reset generator
> -timeout: Watchdog timeout in seconds. 1<= timeout <=15300, default=60
> -nowayout: Watchdog cannot be stopped once started
> +    force_id:
> +	Override the detected device ID
> +    therm_trip:
> +	Should a ThermTrip trigger the reset generator
> +    timeout:
> +	Watchdog timeout in seconds. 1<= timeout <=15300, default=60
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  scx200_wdt:
> -margin: Watchdog margin in seconds
> -nowayout: Disable watchdog shutdown on close
> +    margin:
> +	Watchdog margin in seconds
> +    nowayout:
> +	Disable watchdog shutdown on close
> +
>  -------------------------------------------------
> +
>  shwdt:
> -clock_division_ratio: Clock division ratio. Valid ranges are from 0x5 (1.31ms)
> +    clock_division_ratio:
> +	Clock division ratio. Valid ranges are from 0x5 (1.31ms)
>  	to 0x7 (5.25ms). (default=7)
> -heartbeat: Watchdog heartbeat in seconds. (1 <= heartbeat <= 3600, default=30
> -nowayout: Watchdog cannot be stopped once started
> +    heartbeat:
> +	Watchdog heartbeat in seconds. (1 <= heartbeat <= 3600, default=30
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  smsc37b787_wdt:
> -timeout: range is 1-255 units, default is 60
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	range is 1-255 units, default is 60
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  softdog:
> -soft_margin: Watchdog soft_margin in seconds.
> +    soft_margin:
> +	Watchdog soft_margin in seconds.
>  	(0 < soft_margin < 65536, default=60)
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> -soft_noboot: Softdog action, set to 1 to ignore reboots, 0 to reboot
> +    soft_noboot:
> +	Softdog action, set to 1 to ignore reboots, 0 to reboot
>  	(default=0)
> +
>  -------------------------------------------------
> +
>  stmp3xxx_wdt:
> -heartbeat: Watchdog heartbeat period in seconds from 1 to 4194304, default 19
> +    heartbeat:
> +	Watchdog heartbeat period in seconds from 1 to 4194304, default 19
> +
>  -------------------------------------------------
> +
>  tegra_wdt:
> -heartbeat: Watchdog heartbeats in seconds. (default = 120)
> -nowayout: Watchdog cannot be stopped once started
> +    heartbeat:
> +	Watchdog heartbeats in seconds. (default = 120)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  ts72xx_wdt:
> -timeout: Watchdog timeout in seconds. (1 <= timeout <= 8, default=8)
> -nowayout: Disable watchdog shutdown on close
> +    timeout:
> +	Watchdog timeout in seconds. (1 <= timeout <= 8, default=8)
> +    nowayout:
> +	Disable watchdog shutdown on close
> +
>  -------------------------------------------------
> +
>  twl4030_wdt:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  txx9wdt:
> -timeout: Watchdog timeout in seconds. (0<timeout<N, default=60)
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds. (0<timeout<N, default=60)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  uniphier_wdt:
> -timeout: Watchdog timeout in power of two seconds.
> +    timeout:
> +	Watchdog timeout in power of two seconds.
>  	(1 <= timeout <= 128, default=64)
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  w83627hf_wdt:
> -wdt_io: w83627hf/thf WDT io port (default 0x2E)
> -timeout: Watchdog timeout in seconds. 1 <= timeout <= 255, default=60.
> -nowayout: Watchdog cannot be stopped once started
> +    wdt_io:
> +	w83627hf/thf WDT io port (default 0x2E)
> +    timeout:
> +	Watchdog timeout in seconds. 1 <= timeout <= 255, default=60.
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  w83877f_wdt:
> -timeout: Watchdog timeout in seconds. (1<=timeout<=3600, default=30)
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds. (1<=timeout<=3600, default=30)
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  w83977f_wdt:
> -timeout: Watchdog timeout in seconds (15..7635), default=45)
> -testmode: Watchdog testmode (1 = no reboot), default=0
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds (15..7635), default=45)
> +    testmode:
> +	Watchdog testmode (1 = no reboot), default=0
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  wafer5823wdt:
> -timeout: Watchdog timeout in seconds. 1 <= timeout <= 255, default=60.
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds. 1 <= timeout <= 255, default=60.
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  wdt285:
> -soft_margin: Watchdog timeout in seconds (default=60)
> +    soft_margin:
> +	Watchdog timeout in seconds (default=60)
> +
>  -------------------------------------------------
> +
>  wdt977:
> -timeout: Watchdog timeout in seconds (60..15300, default=60)
> -testmode: Watchdog testmode (1 = no reboot), default=0
> -nowayout: Watchdog cannot be stopped once started
> +    timeout:
> +	Watchdog timeout in seconds (60..15300, default=60)
> +    testmode:
> +	Watchdog testmode (1 = no reboot), default=0
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  wm831x_wdt:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  wm8350_wdt:
> -nowayout: Watchdog cannot be stopped once started
> +    nowayout:
> +	Watchdog cannot be stopped once started
>  	(default=kernel config parameter)
> +
>  -------------------------------------------------
> +
>  sun4v_wdt:
> -timeout_ms: Watchdog timeout in milliseconds 1..180000, default=60000)
> -nowayout: Watchdog cannot be stopped once started
> --------------------------------------------------
> +    timeout_ms:
> +	Watchdog timeout in milliseconds 1..180000, default=60000)
> +    nowayout:
> +	Watchdog cannot be stopped once started
> diff --git a/Documentation/watchdog/watchdog-pm.txt b/Documentation/watchdog/watchdog-pm.txt
> index 7a4dd46e0d24..646e1f28f31f 100644
> --- a/Documentation/watchdog/watchdog-pm.txt
> +++ b/Documentation/watchdog/watchdog-pm.txt
> @@ -1,5 +1,7 @@
> +===============================================
>  The Linux WatchDog Timer Power Management Guide
>  ===============================================
> +
>  Last reviewed: 17-Dec-2018
>  
>  Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> @@ -16,4 +18,5 @@ On resume, a watchdog timer shall be reset to its selected value to give
>  userspace enough time to resume. [1] [2]
>  
>  [1] https://patchwork.kernel.org/patch/10252209/
> +
>  [2] https://patchwork.kernel.org/patch/10711625/
> diff --git a/Documentation/watchdog/wdt.txt b/Documentation/watchdog/wdt.txt
> index ed2f0b860869..d97b0361535b 100644
> --- a/Documentation/watchdog/wdt.txt
> +++ b/Documentation/watchdog/wdt.txt
> @@ -1,11 +1,14 @@
> +============================================================
> +WDT Watchdog Timer Interfaces For The Linux Operating System
> +============================================================
> +
>  Last Reviewed: 10/05/2007
>  
> -	WDT Watchdog Timer Interfaces For The Linux Operating System
> -		Alan Cox <alan@xxxxxxxxxxxxxxxxxxx>
> +Alan Cox <alan@xxxxxxxxxxxxxxxxxxx>
>  
> -	ICS	WDT501-P
> -	ICS	WDT501-P (no fan tachometer)
> -	ICS	WDT500-P
> +	- ICS	WDT501-P
> +	- ICS	WDT501-P (no fan tachometer)
> +	- ICS	WDT500-P
>  
>  All the interfaces provide /dev/watchdog, which when open must be written
>  to within a timeout or the machine will reboot. Each write delays the reboot
> @@ -21,19 +24,26 @@ degrees Fahrenheit. Each read returns a single byte giving the temperature.
>  The third interface logs kernel messages on additional alert events.
>  
>  The ICS ISA-bus wdt card cannot be safely probed for. Instead you need to
> -pass IO address and IRQ boot parameters.  E.g.:
> +pass IO address and IRQ boot parameters.  E.g.::
> +
>  	wdt.io=0x240 wdt.irq=11
>  
>  Other "wdt" driver parameters are:
> +
> +	===========	======================================================
>  	heartbeat	Watchdog heartbeat in seconds (default 60)
>  	nowayout	Watchdog cannot be stopped once started (kernel
> -				build parameter)
> +			build parameter)
>  	tachometer	WDT501-P Fan Tachometer support (0=disable, default=0)
>  	type		WDT501-P Card type (500 or 501, default=500)
> +	===========	======================================================
>  
>  Features
>  --------
> -		WDT501P		WDT500P
> +
> +================   =======	   =======
> +		   WDT501P	   WDT500P
> +================   =======	   =======
>  Reboot Timer	   X               X
>  External Reboot	   X	           X
>  I/O Port Monitor   o		   o
> @@ -42,9 +52,12 @@ Fan Speed          X		   o
>  Power Under	   X               o
>  Power Over         X               o
>  Overheat           X               o
> +================   =======	   =======
>  
>  The external event interfaces on the WDT boards are not currently supported.
>  Minor numbers are however allocated for it.
>  
>  
> -Example Watchdog Driver:  see samples/watchdog/watchdog-simple.c
> +Example Watchdog Driver:
> +
> +	see samples/watchdog/watchdog-simple.c
> -- 
> 2.20.1
> 




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