On SBSA platforms using standard UEFI firmware (such as EDK II), the
watchdog timer is often enabled during early boot stages but explicitly
disabled by the firmware before handing over control to the OS (e.g.,
during ExitBootServices). This is done to prevent unintended resets
while the OS is loading, assuming the OS watchdog driver will take over.

However, this leaves a protection gap. If the system hangs between the
firmware handover and the userspace watchdog daemon startup, the hardware
watchdog will not fire to recover the system. For safety-critical systems
that require continuous hardware watchdog protection from the earliest
possible moment, this gap is problematic.

Add an 'early_enable' module parameter to allow the kernel driver to
re-enable the watchdog immediately during probe if it was left disabled
by the firmware. By setting the WDOG_HW_RUNNING status bit, the watchdog
core is instructed that the hardware is active. As a result, the core's
pre-userspace handler (controlled by 'handle_boot_enabled') will
automatically issue periodic keepalives until userspace opens the device.

This bridges the protection gap seamlessly without requiring firmware
modifications and without risking unintended resets during kernel boot.

The parameter defaults to false to preserve the traditional behavior.

Signed-off-by: Zexin Wang <ot_zexin.wang@mediatek.com>
Link: https://patch.msgid.link/20260817023838.6459-1-ot_zexin.wang@mediatek.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Add documentation describing how the NPCM watchdog driver reports reset
causes through bootstatus on NPCM750 and NPCM845 systems.

Document the reset flag mapping, the watchdog instance mapping for
WDIOF_CARDRESET, and the NPCM750/NPCM845 latch handling. Also mention
sysfs bootstatus reporting when watchdog sysfs support is enabled.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Link: https://lore.kernel.org/r/20260706144828.3517631-3-tmaimon77@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Add missing brackets ')'.

Signed-off-by: Manuel Ebner <manuelebner@mailbox.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20260627091707.29688-2-manuelebner@mailbox.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Pull documentation updates from Jonathan Corbet:
 "Things have calmed down a bit on the docs front, with no earthshaking
  changes this time around:

   - Ongoing work on the Japanese and Portuguese translations

   - Better integration of the MAINTAINERS file into the rendered
     documents, including a search interface

   - A seemingly infinite supply of fixes for typos, minor grammatical
     issues, and related problems that LLMs find with abandon"

* tag 'docs-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: (93 commits)
  docs: pt_BR: Translate 3.Early-stage.rst into Portuguese
  docs: pt_BR: update "Purpose of Defconfigs" section in maintainer-soc.rst
  Documentation: bug-hunting.rst: fix grammar
  docs/ja_JP: translate submitting-patches.rst (interleaved-replies)
  docs: Fix minor grammatical error
  docs/{it_it,sp_SP,zh_CN,zh_TW}: update references to removed CONFIG_DEBUG_SLAB
  Documentation: process: fix brackets
  Documentation: arch: fix brackets
  docs/dyndbg: explain flags parse 1st
  docs/dyndbg: update examples \012 to \n
  docs: kernel-parameters: Fix stale sticore file paths
  docs: real-time: Fix duplicated sched(7) text
  docs: kgdb: Fix stale source file paths
  docs: sonypi: Fix stale header file path
  docs: kernel-parameters: Remove sa1100ir IrDA parameter
  iommu: Documentation: rearrange, update kernel-parameters
  docs: md: fix grammar in speed_limit description
  docs: changes.rst: restore pahole 1.26 minimum (regressed by sort)
  Documentation: Fix syntax of kmalloc_objs example in coding style doc
  docs: pt_BR: update maintainer-handbooks
  ...

devm_watchdog_register_device() is not documented. Add it to the current
kernel API documentation.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

AMD Elan support was removed from the upstream kernel with commit
8b793a92d862 ("x86/cpu: Remove M486/M486SX/ELAN support"). Its
watchdog driver can no longer be enabled except for test builds.
Remove it.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>

`wdt.rst` is only about the Watchdog from "Industrial Computer Source"
(ICS). Change the title and rename the file to better express this.

Add missing SPDX license identifier `GPL-2.0-or-later` same as code to
silence `checkpatch`.

Fix wrong link to sample driver in drivers/watchdog/smsc37b787_wdt.c.

Signed-off-by: Philipp Hahn <phahn-oss@avm.de>
Link: https://lore.kernel.org/r/5a71979d8e8ab8e0a30de33f6aa2540b3b5dc1ee.1777972790.git.phahn-oss@avm.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Currently there are several (sub-)documents for "Generic kernel
infrastructure API" and several "driver specific" documents. Put each
one into its own sub-section.

Signed-off-by: Philipp Hahn <phahn-oss@avm.de>
Link: https://lore.kernel.org/r/7d1b722205bab83603832e66750f7b5f1f73eaa5.1777972790.git.phahn-oss@avm.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Consistently indent all lines with tabs instead of having one line using
blanks.

Signed-off-by: Philipp Hahn <phahn-oss@avm.de>
Link: https://lore.kernel.org/r/e1ccbfb0efb9a9f508d1afe10263af1578a1aa46.1777972790.git.phahn-oss@avm.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Write `struct ` before the structure name as Sphinx otherwise uses the
following word after it. See
https://docs.kernel.org/watchdog/watchdog-api.html#environmental-monitoring

Signed-off-by: Philipp Hahn <phahn-oss@avm.de>
Link: https://lore.kernel.org/r/e66ec58f3b8252b3676cc9fe68818af95123210c.1777972790.git.phahn-oss@avm.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>