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Huacai Chen 01ef7f1b87 USB: OHCI/UHCI: Add soft dependencies on ehci_platform
Commit 9beeee6584 ("USB: EHCI: log a warning if ehci-hcd is not
loaded first") said that ehci-hcd should be loaded before ohci-hcd and
uhci-hcd. However, commit 05c92da0c5 ("usb: ohci/uhci - add soft
dependencies on ehci_pci") only makes ohci-pci/uhci-pci depend on ehci-
pci, which is not enough and we may still see the warnings in boot log.

To eliminate the warnings we should make ohci-hcd/uhci-hcd depend on
ehci-hcd. But Alan said that the warning introduced by 9beeee6584
is bogus, we only need the soft dependencies in the PCI level rather
than the HCD level.

However, there is really another neccessary soft dependencies between
ohci-platform/uhci-platform and ehci-platform, which is added by this
patch. The boot logs are below.

1. ohci-platform loaded before ehci-platform:

 ohci-platform 1f058000.usb: Generic Platform OHCI controller
 ohci-platform 1f058000.usb: new USB bus registered, assigned bus number 1
 ohci-platform 1f058000.usb: irq 28, io mem 0x1f058000
 hub 1-0:1.0: USB hub found
 hub 1-0:1.0: 4 ports detected
 Warning! ehci_hcd should always be loaded before uhci_hcd and ohci_hcd, not after
 usb 1-4: new low-speed USB device number 2 using ohci-platform
 ehci-platform 1f050000.usb: EHCI Host Controller
 ehci-platform 1f050000.usb: new USB bus registered, assigned bus number 2
 ehci-platform 1f050000.usb: irq 29, io mem 0x1f050000
 ehci-platform 1f050000.usb: USB 2.0 started, EHCI 1.00
 usb 1-4: device descriptor read/all, error -62
 hub 2-0:1.0: USB hub found
 hub 2-0:1.0: 4 ports detected
 usb 1-4: new low-speed USB device number 3 using ohci-platform
 input: YSPRINGTECH USB OPTICAL MOUSE as /devices/platform/bus@10000000/1f058000.usb/usb1/1-4/1-4:1.0/0003:10C4:8105.0001/input/input0
 hid-generic 0003:10C4:8105.0001: input,hidraw0: USB HID v1.11 Mouse [YSPRINGTECH USB OPTICAL MOUSE] on usb-1f058000.usb-4/input0

2. ehci-platform loaded before ohci-platform:

 ehci-platform 1f050000.usb: EHCI Host Controller
 ehci-platform 1f050000.usb: new USB bus registered, assigned bus number 1
 ehci-platform 1f050000.usb: irq 28, io mem 0x1f050000
 ehci-platform 1f050000.usb: USB 2.0 started, EHCI 1.00
 hub 1-0:1.0: USB hub found
 hub 1-0:1.0: 4 ports detected
 ohci-platform 1f058000.usb: Generic Platform OHCI controller
 ohci-platform 1f058000.usb: new USB bus registered, assigned bus number 2
 ohci-platform 1f058000.usb: irq 29, io mem 0x1f058000
 hub 2-0:1.0: USB hub found
 hub 2-0:1.0: 4 ports detected
 usb 2-4: new low-speed USB device number 2 using ohci-platform
 input: YSPRINGTECH USB OPTICAL MOUSE as /devices/platform/bus@10000000/1f058000.usb/usb2/2-4/2-4:1.0/0003:10C4:8105.0001/input/input0
 hid-generic 0003:10C4:8105.0001: input,hidraw0: USB HID v1.11 Mouse [YSPRINGTECH USB OPTICAL MOUSE] on usb-1f058000.usb-4/input0

In the later case, there is no re-connection for USB-1.0/1.1 devices,
which is expected.

Cc: stable <stable@kernel.org>
Reported-by: Shengwen Xiao <atzlinux@sina.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://patch.msgid.link/20260112084802.1995923-1-chenhuacai@loongson.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-14 16:02:14 +01:00
arch RISC-V updates for v6.19-rc3 2025-12-28 09:44:26 -08:00
block block-6.19-20251218 2025-12-20 09:48:56 -08:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto Networking changes for 6.19. 2025-12-03 17:24:33 -08:00
Documentation dt-bindings: usb: qcom,dwc3: Correct MSM8994 interrupts 2026-01-07 16:28:15 +01:00
drivers USB: OHCI/UHCI: Add soft dependencies on ehci_platform 2026-01-14 16:02:14 +01:00
fs smb3 client fix 2025-12-26 16:19:45 -08:00
include usb: core: add USB_QUIRK_NO_BOS for devices that hang on BOS descriptor 2026-01-07 17:07:00 +01:00
init Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
io_uring io_uring-6.19-20251226 2025-12-26 11:34:38 -08:00
ipc Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
kernel EFI fixes for v6.19 #1 2025-12-26 13:37:11 -08:00
lib linux_kselftest-kunit-fixes-6.19-rc3 2025-12-20 11:59:06 -08:00
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 slab fix for 6.19-rc2 2025-12-20 11:24:42 -08:00
net nfsd-6.19 fixes: 2025-12-24 09:23:04 -08:00
rust rust: dma: add helpers for architectures without CONFIG_HAS_DMA 2025-12-16 13:20:14 +01:00
samples samples: rust: fix endianness issue in rust_driver_pci 2025-12-17 18:10:58 +01:00
scripts Coccinelle: pm_runtime: Fix typo in report message 2025-12-21 21:04:52 +01:00
security Trivial optimization. 2025-12-14 15:21:02 +12:00
sound ALSA: hda/realtek: fix PCI SSID for one of the HP 200 G2i laptop 2025-12-21 11:19:31 +01:00
tools powerpc fixes for 6.19 #2 2025-12-28 09:40:09 -08:00
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 Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.rustfmt.toml
COPYING
CREDITS Including fixes from netfilter and CAN. 2025-12-19 07:55:35 +12:00
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 regulator: Add UAPI headers to MAINTAINERS 2025-12-22 09:00:43 +00:00
Makefile Linux 6.19-rc3 2025-12-28 13:24:26 -08:00
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