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Luke Wang 1db87818bd mmc: sdhci-esdhc-imx: restore pinctrl before restoring ios timing on resume
SDIO devices such as WiFi may keep power during suspend, so the MMC
core skips full card re-initialization on resume and directly restores
the host controller's ios timing to match the card. For DDR mode,
pm_runtime_force_resume() sets DDR_EN before the pin configuration is
restored from sleep state.

This is related to the SoC IP integration: switching pinctrl setting
(changing alt from GPIO to USDHC) impacts the internal loopback path.
If pinctrl configures the pad to GPIO function, once DDR_EN is set, the
DLL delay will be fixed based on the GPIO function loopback path. When
the pinctrl is later changed to USDHC function, the internal loopback
path changes, making the original fixed sample point no longer suitable
for the current loopback path. This causes persistent read CRC errors on
subsequent data transfers.

SD/eMMC running in DDR mode are unaffected as they are fully
re-initialized from legacy timing after resume.

Fix this by restoring the pinctrl state based on current timing mode
using esdhc_change_pinstate() before pm_runtime_force_resume(). This
ensures the correct pin configuration (e.g., 100/200MHz for UHS modes)
is applied before DDR_EN is set. Only restore for non-wakeup devices
since wakeup devices kept their active pin state during suspend.

Fixes: 676a838556 ("mmc: host: sdhci-esdhc-imx: refactor the system PM logic")
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Haibo Chen <haibo.chen@nxp.com>
Signed-off-by: Luke Wang <ziniu.wang_1@nxp.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-07-15 10:59:36 +02:00
arch - Prevent OOB access in the resctrl code while offlining 2026-07-05 05:37:46 -10:00
block block: handle REQ_OP_ZONE_APPEND in __bio_integrity_action 2026-06-24 06:53:25 -06:00
certs treewide: fix indentation and whitespace in Kconfig files 2026-05-28 21:24:42 -07:00
crypto mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -07:00
Documentation dt-bindings: mmc: mtk-sd: Document extra clocks for MT8189 2026-07-06 17:03:58 +02:00
drivers mmc: sdhci-esdhc-imx: restore pinctrl before restoring ios timing on resume 2026-07-15 10:59:36 +02:00
fs - Prevent OOB access in the resctrl code while offlining 2026-07-05 05:37:46 -10:00
include drm fixes for 7.2-rc2 2026-07-03 15:42:20 -10:00
init mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -07:00
io_uring io_uring-7.2-20260625 2026-06-25 09:53:31 -07:00
ipc kernel-7.2-rc1.misc 2026-06-15 03:05:50 +05:30
kernel Misc perf events fixes: 2026-07-05 05:34:43 -10:00
lib RISC-V updates for v7.2-rc2 2026-07-03 15:07:24 -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 block-7.2-20260625 2026-06-25 09:56:47 -07:00
net Split <linux/mod_devicetable.h> in per subsystem headers 2026-07-02 20:54:26 -10:00
rust Rust changes for v7.2 (addendum) 2026-06-24 15:11:08 -07:00
samples tracing/events: Fix to check the simple_tsk_fn creation 2026-06-30 23:58:19 +09:00
scripts scripts/sorttable: Handle RISC-V patchable ftrace entries 2026-06-25 13:15:03 -06:00
security bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized 2026-06-30 16:31:56 +02:00
sound sound fixes for 7.2-rc2 2026-07-05 05:26:45 -10:00
tools Misc perf events fixes: 2026-07-05 05:34:43 -10:00
usr kbuild: uapi: also test UAPI headers against C++ compilers 2026-03-25 13:24:42 +01:00
virt s390: 2026-06-25 10:21:13 -07:00
.clang-format clang-format: fix formatting of guard() and scoped_guard() statements 2026-05-28 21:24:41 -07:00
.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 SPDX patches for 7.2-rc1 2026-06-22 12:06:22 -07:00
.mailmap MAINTAINERS: Update Jason Wang's email address 2026-06-29 19:09:00 -07:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml
COPYING
CREDITS mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -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 sound fixes for 7.2-rc2 2026-07-05 05:26:45 -10:00
Makefile Linux 7.2-rc2 2026-07-05 14:44:06 -10:00
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