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Tommaso Merciai e383f09614 i2c: riic: Move suspend handling to NOIRQ phase
Commit 53326135d0 ("i2c: riic: Add suspend/resume support") added
suspend support for the Renesas I2C driver and following this change
on RZ/G3E the following WARNING is seen on entering suspend ...

[  134.275704] Freezing remaining freezable tasks completed (elapsed 0.001 seconds)
[  134.285536] ------------[ cut here ]------------
[  134.290298] i2c i2c-2: Transfer while suspended
[  134.295174] WARNING: drivers/i2c/i2c-core.h:56 at __i2c_smbus_xfer+0x1e4/0x214, CPU#0: systemd-sleep/388
[  134.365507] Tainted: [W]=WARN
[  134.368485] Hardware name: Renesas SMARC EVK version 2 based on r9a09g047e57 (DT)
[  134.375961] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  134.382935] pc : __i2c_smbus_xfer+0x1e4/0x214
[  134.387329] lr : __i2c_smbus_xfer+0x1e4/0x214
[  134.391717] sp : ffff800083f23860
[  134.395040] x29: ffff800083f23860 x28: 0000000000000000 x27: ffff800082ed5d60
[  134.402226] x26: 0000001f4395fd74 x25: 0000000000000007 x24: 0000000000000001
[  134.409408] x23: 0000000000000000 x22: 000000000000006f x21: ffff800083f23936
[  134.416589] x20: ffff0000c090e140 x19: ffff0000c090e0d0 x18: 0000000000000006
[  134.423771] x17: 6f63657320313030 x16: 2e30206465737061 x15: ffff800083f23280
[  134.430953] x14: 0000000000000000 x13: ffff800082b16ce8 x12: 0000000000000f09
[  134.438134] x11: 0000000000000503 x10: ffff800082b6ece8 x9 : ffff800082b16ce8
[  134.445315] x8 : 00000000ffffefff x7 : ffff800082b6ece8 x6 : 80000000fffff000
[  134.452495] x5 : 0000000000000504 x4 : 0000000000000000 x3 : 0000000000000000
[  134.459672] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000c9ee9e80
[  134.466851] Call trace:
[  134.469311]  __i2c_smbus_xfer+0x1e4/0x214 (P)
[  134.473715]  i2c_smbus_xfer+0xbc/0x120
[  134.477507]  i2c_smbus_read_byte_data+0x4c/0x84
[  134.482077]  isl1208_i2c_read_time+0x44/0x178 [rtc_isl1208]
[  134.487703]  isl1208_rtc_read_time+0x14/0x20 [rtc_isl1208]
[  134.493226]  __rtc_read_time+0x44/0x88
[  134.497012]  rtc_read_time+0x3c/0x68
[  134.500622]  rtc_suspend+0x9c/0x170

The warning is triggered because I2C transfers can still be attempted
while the controller is already suspended, due to inappropriate ordering
of the system sleep callbacks.

If the controller is autosuspended, there is no way to wake it up once
runtime PM disabled (in suspend_late()). During system resume, the I2C
controller will be available only after runtime PM is re-enabled
(in resume_early()). However, this may be too late for some devices.

Wake up the controller in the suspend() callback while runtime PM is
still enabled. The I2C controller will remain available until the
suspend_noirq() callback (pm_runtime_force_suspend()) is called. During
resume, the I2C controller can be restored by the resume_noirq() callback
(pm_runtime_force_resume()). Finally, the resume() callback re-enables
autosuspend. As a result, the I2C controller can remain available until
the system enters suspend_noirq() and from resume_noirq().

Cc: stable@vger.kernel.org
Fixes: 53326135d0 ("i2c: riic: Add suspend/resume support")
Signed-off-by: Tommaso Merciai <tommaso.merciai.xr@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Tested-by: Biju Das <biju.das.jz@bp.renesas.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2026-01-13 17:13:50 +01:00
arch Disable GCOV instrumentation in the SEV noinstr.c collection 2026-01-11 07:19:43 -10:00
block block-6.19-20260109 2026-01-09 15:42:46 -10:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: seqiv - Do not use req->iv after crypto_aead_encrypt 2025-12-19 14:47:06 +08:00
Documentation dt-bindings: i2c: brcm,iproc-i2c: Allow 2 reg entries for brcm,iproc-nic-i2c 2026-01-13 16:30:22 +01:00
drivers i2c: riic: Move suspend handling to NOIRQ phase 2026-01-13 17:13:50 +01:00
fs treewide: Update email address 2026-01-11 06:09:11 -10:00
include treewide: Update email address 2026-01-11 06:09:11 -10:00
init Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
io_uring io_uring-6.19-20260109 2026-01-09 15:21:15 -10:00
ipc Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
kernel Fix a crash in sched_mm_cid_after_execve(). 2026-01-11 07:11:53 -10:00
lib Crypto library fixes for v6.19-rc5 2026-01-11 15:07:56 -10:00
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 mm/ksm: fix pte_unmap_unlock of wrong address in break_ksm_pmd_entry 2025-12-23 11:23:17 -08:00
net A bunch of libceph fixes split evenly between memory safety and 2026-01-09 15:05:19 -10:00
rust Driver core fixes for 6.19-rc5 2026-01-10 15:04:04 -10:00
samples samples/ftrace: Adjust LoongArch register restore order in direct calls 2025-12-31 15:19:25 +08:00
scripts Crypto library fixes for v6.19-rc5 2026-01-11 15:07:56 -10:00
security kernel/kexec: change the prototype of kimage_map_segment() 2025-12-23 11:23:13 -08:00
sound ALSA: hda/realtek: add HP Laptop 15s-eq1xxx mute LED quirk 2026-01-02 14:34:23 +01:00
tools treewide: Update email address 2026-01-11 06:09:11 -10:00
usr initramfs: add gen_init_cpio to hostprogs unconditionally 2025-11-26 21:55:40 +01:00
virt KVM fixes for 6.19-rc1 2025-12-18 18:38:45 +01:00
.clang-format s390/pci: Fix cyclic dead-lock in zpci_zdev_put() and zpci_scan_devices() 2025-12-14 11:03:58 +01:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore rust: kbuild: add proc macro library support 2025-11-24 17:15:36 +01:00
.mailmap treewide: Update email address 2026-01-11 06:09:11 -10:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml
COPYING
CREDITS treewide: Update email address 2026-01-11 06:09:11 -10:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS Crypto library fixes for v6.19-rc5 2026-01-11 15:07:56 -10:00
Makefile Linux 6.19-rc5 2026-01-11 17:03:14 -10:00
README README: restructure with role-based documentation and guidelines 2025-11-29 08:40:33 -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


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



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