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David Carlier 6ee2ba9dce
i2c: ls2x-v2: return IRQ_HANDLED after servicing an error
The event ISR reads SR1 and, when an error flag (ARLO/AF/BERR) is set,
calls loongson2_i2c_isr_error() which clears the offending flag, issues
STOP for the AF case, records msg->result, masks every CR2 interrupt
enable and completes the waiter. The handler then returns IRQ_NONE,
declaring to the IRQ core that the device did not interrupt.

That report is wrong. The device did interrupt and the handler fully
serviced it. Because the IRQ is requested with IRQF_SHARED, the genirq
spurious-IRQ tracker counts each error as unhandled. A bus that emits
sporadic NACKs, arbitration losses or bus errors will therefore march
toward the spurious-IRQ threshold and the line can end up disabled,
wedging the controller.

Return IRQ_HANDLED on this path. The other IRQ_NONE site, taken when
neither an event nor an error bit is set, remains correct.

Fixes: 6d1b0785f6 ("i2c: ls2x-v2: Add driver for Loongson-2K0300 I2C controller")
Signed-off-by: David Carlier <devnexen@gmail.com>
Assisted-by: Codex:GPT-5.5
Reviewed-by: Binbin Zhou <zhoubinbin@loongson.cn>
Tested-by: Binbin Zhou <zhoubinbin@loongson.cn>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20260506154015.94815-1-devnexen@gmail.com
2026-06-17 01:19:53 +02:00
arch gpio updates for v7.2-rc1 2026-06-16 07:30:52 +05:30
block block-7.1-20260529 2026-05-29 10:41:07 -07:00
certs Clang build fixes for 7.1 2026-04-24 09:29:51 -07:00
crypto crypto/krb5, rxrpc: Fix lack of pre-decrypt/pre-verify length checks 2026-05-20 16:36:45 -07:00
Documentation dt-bindings: i2c: i2c-mux-pinctrl: change maintainer 2026-06-16 15:01:25 +02:00
drivers i2c: ls2x-v2: return IRQ_HANDLED after servicing an error 2026-06-17 01:19:53 +02:00
fs Preparatory work for MPAM counter assignment: 2026-06-16 05:35:40 +05:30
include i2c: atr: annotate i2c_atr_adap_desc->aliases with __counted_by_ptr 2026-06-17 00:15:09 +02:00
init Scheduler updates for v7.2: 2026-06-15 14:50:18 +05:30
io_uring Locking updates for v7.2: 2026-06-15 14:21:14 +05:30
ipc kernel-7.2-rc1.misc 2026-06-15 03:05:50 +05:30
kernel Scheduler updates for v7.2: 2026-06-15 14:50:18 +05:30
lib gpio updates for v7.2-rc1 2026-06-16 07:30:52 +05:30
LICENSES LICENSES: Add modern form of the LGPL-2.1 tags to the usage guide section 2025-10-22 07:58:19 +02:00
mm arm64 updates for 7.2 2026-06-16 05:18:04 +05:30
net Updates for the time/timer core subsystem: 2026-06-15 13:39:12 +05:30
rust s390 updates for 7.2 merge window 2026-06-16 05:08:13 +05:30
samples Driver core changes for 7.2-rc1 2026-06-15 12:41:17 +05:30
scripts - Move the zero-revision fixup for AMD microcode to the patch level 2026-06-16 05:45:36 +05:30
security Kbuild / Kconfig changes for 7.2 2026-06-15 05:01:15 +05:30
sound gpio updates for v7.2-rc1 2026-06-16 07:30:52 +05:30
tools arm64 updates for 7.2 2026-06-16 05:18:04 +05:30
usr kbuild: uapi: also test UAPI headers against C++ compilers 2026-03-25 13:24:42 +01:00
virt vfs-7.2-rc1.misc 2026-06-15 03:59:45 +05:30
.clang-format Devicetree updates for v7.0: 2026-02-11 18:27:08 -08:00
.clippy.toml rust: bump Clippy's MSRV and clean incompatible_msrv allows 2026-04-07 09:51:39 +02:00
.cocciconfig
.editorconfig editorconfig: add rst extension 2026-01-26 19:07:09 -08:00
.get_maintainer.ignore .get_maintainer.ignore: add myself 2026-04-02 16:48:25 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Rust changes for v7.2 2026-06-15 09:25:48 +05:30
.mailmap MAINTAINERS: update Baoquan He's email address 2026-06-03 16:25:50 -07:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml
COPYING
CREDITS MAINTAINERS: Drop obsolete FPU EMULATOR section 2026-05-29 19:56:02 -07:00
Kbuild checksyscalls: move instance functionality into generic code 2026-04-05 09:21:32 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS i2c for v7.2 2026-06-16 07:43:29 +05:30
Makefile Rust changes for v7.2 2026-06-15 09:25:48 +05:30
README docs: add AI Coding Assistants documentation 2026-01-06 14:55:06 -07:00

Linux kernel
============

The Linux kernel is the core of any Linux operating system. It manages hardware,
system resources, and provides the fundamental services for all other software.

Quick Start
-----------

* Report a bug: See Documentation/admin-guide/reporting-issues.rst
* Get the latest kernel: https://kernel.org
* Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst
* Join the community: https://lore.kernel.org/

Essential Documentation
-----------------------

All users should be familiar with:

* Building requirements: Documentation/process/changes.rst
* Code of Conduct: Documentation/process/code-of-conduct.rst
* License: See COPYING

Documentation can be built with make htmldocs or viewed online at:
https://www.kernel.org/doc/html/latest/


Who Are You?
============

Find your role below:

* New Kernel Developer - Getting started with kernel development
* Academic Researcher - Studying kernel internals and architecture
* Security Expert - Hardening and vulnerability analysis
* Backport/Maintenance Engineer - Maintaining stable kernels
* System Administrator - Configuring and troubleshooting
* Maintainer - Leading subsystems and reviewing patches
* Hardware Vendor - Writing drivers for new hardware
* Distribution Maintainer - Packaging kernels for distros
* AI Coding Assistant - LLMs and AI-powered development tools


For Specific Users
==================

New Kernel Developer
--------------------

Welcome! Start your kernel development journey here:

* Getting Started: Documentation/process/development-process.rst
* Your First Patch: Documentation/process/submitting-patches.rst
* Coding Style: Documentation/process/coding-style.rst
* Build System: Documentation/kbuild/index.rst
* Development Tools: Documentation/dev-tools/index.rst
* Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst
* Core APIs: Documentation/core-api/index.rst

Academic Researcher
-------------------

Explore the kernel's architecture and internals:

* Researcher Guidelines: Documentation/process/researcher-guidelines.rst
* Memory Management: Documentation/mm/index.rst
* Scheduler: Documentation/scheduler/index.rst
* Networking Stack: Documentation/networking/index.rst
* Filesystems: Documentation/filesystems/index.rst
* RCU (Read-Copy Update): Documentation/RCU/index.rst
* Locking Primitives: Documentation/locking/index.rst
* Power Management: Documentation/power/index.rst

Security Expert
---------------

Security documentation and hardening guides:

* Security Documentation: Documentation/security/index.rst
* LSM Development: Documentation/security/lsm-development.rst
* Self Protection: Documentation/security/self-protection.rst
* Reporting Vulnerabilities: Documentation/process/security-bugs.rst
* CVE Procedures: Documentation/process/cve.rst
* Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst
* Security Features: Documentation/userspace-api/seccomp_filter.rst

Backport/Maintenance Engineer
-----------------------------

Maintain and stabilize kernel versions:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* Backporting Guide: Documentation/process/backporting.rst
* Applying Patches: Documentation/process/applying-patches.rst
* Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git for Maintainers: Documentation/maintainer/configure-git.rst

System Administrator
--------------------

Configure, tune, and troubleshoot Linux systems:

* Admin Guide: Documentation/admin-guide/index.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst
* Tracing/Debugging: Documentation/trace/index.rst
* Performance Security: Documentation/admin-guide/perf-security.rst
* Hardware Monitoring: Documentation/hwmon/index.rst

Maintainer
----------

Lead kernel subsystems and manage contributions:

* Maintainer Handbook: Documentation/maintainer/index.rst
* Pull Requests: Documentation/maintainer/pull-requests.rst
* Managing Patches: Documentation/maintainer/modifying-patches.rst
* Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst
* Development Process: Documentation/process/maintainer-handbooks.rst
* Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git Configuration: Documentation/maintainer/configure-git.rst

Hardware Vendor
---------------

Write drivers and support new hardware:

* Driver API Guide: Documentation/driver-api/index.rst
* Driver Model: Documentation/driver-api/driver-model/driver.rst
* Device Drivers: Documentation/driver-api/infrastructure.rst
* Bus Types: Documentation/driver-api/driver-model/bus.rst
* Device Tree Bindings: Documentation/devicetree/bindings/
* Power Management: Documentation/driver-api/pm/index.rst
* DMA API: Documentation/core-api/dma-api.rst

Distribution Maintainer
-----------------------

Package and distribute the kernel:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* ABI Documentation: Documentation/ABI/README
* Kernel Configuration: Documentation/kbuild/kconfig.rst
* Module Signing: Documentation/admin-guide/module-signing.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst

AI Coding Assistant
-------------------

CRITICAL: If you are an LLM or AI-powered coding assistant, you MUST read and
follow the AI coding assistants documentation before contributing to the Linux
kernel:

* Documentation/process/coding-assistants.rst

This documentation contains essential requirements about licensing, attribution,
and the Developer Certificate of Origin that all AI tools must comply with.


Communication and Support
=========================

* Mailing Lists: https://lore.kernel.org/
* IRC: #kernelnewbies on irc.oftc.net
* Bugzilla: https://bugzilla.kernel.org/
* MAINTAINERS file: Lists subsystem maintainers and mailing lists
* Email Clients: Documentation/process/email-clients.rst