Rong Zhang db4cd7d6c5 ALSA: usb-audio: Add quirk flags for JBL Pebbles
JBL Pebbles is a pair of desktop speakers with UAC interface. Its
Playback and Capture mixers use linear volume with val = 0/999/1 and
0/3996/4. Meanwhile, the reported sample rates are truncated to
multiples of 0x100 (i.e., 44100 => 44032), resulting in noisy kmsg, as a
warning message is printed each time a stream is opened.

Add a quirk table entry matching VID/PID=0x05fc/0x0231 and applying
linear volume and sample rate quirk flags, so that it can work properly.

Also note that the volume control knob on device is an incremental
encoder. It does nothing but sends KEY_VOLUMEUP and KEY_VOLUMEDOWN per
rotation, controlling the UAC Playback volume mixer indirectly. Hence,
the linear volume quirk flags also enable the volume control knob to
function properly.

Quirky device sample:

  usb 5-1.1: new full-speed USB device number 12 using xhci_hcd
  usb 5-1.1: New USB device found, idVendor=05fc, idProduct=0231, bcdDevice= 1.00
  usb 5-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
  usb 5-1.1: Product: JBL Pebbles
  usb 5-1.1: Manufacturer: Harman International Industries
  usb 5-1.1: SerialNumber: 1.0.0
  usb-storage 5-1.1:1.0: USB Mass Storage device detected
  scsi host0: usb-storage 5-1.1:1.0
  usb 5-1.1: Found last interface = 1
  usb 5-1.1: 2:1: add audio endpoint 0x5
  usb 5-1.1: Creating new data endpoint #5
  usb 5-1.1: 2:1 Set sample rate 44100, clock 0
  usb 5-1.1: current rate 44032 is different from the runtime rate 44100
  usb 5-1.1: 3:1: add audio endpoint 0x84
  usb 5-1.1: Creating new data endpoint #84
  usb 5-1.1: 3:1 Set sample rate 44100, clock 0
  usb 5-1.1: current rate 44032 is different from the runtime rate 44100
  usb 5-1.1: [2] FU [PCM Playback Switch] ch = 1, val = 0/1/1
  usb 5-1.1: Warning! Unlikely big volume step count (=999), linear volume or wrong cval->res?
  usb 5-1.1: [2] FU [PCM Playback Volume] ch = 2, val = 0/999/1
  usb 5-1.1: [5] FU [Mic Capture Switch] ch = 1, val = 0/1/1
  usb 5-1.1: Warning! Unlikely big volume step count (=999), linear volume or wrong cval->res?
  usb 5-1.1: [5] FU [Mic Capture Volume] ch = 2, val = 0/3996/4
  input: Harman International Industries JBL Pebbles as /devices/pci0000:00/0000:00:08.3/0000:67:00.3/usb5/5-1/5-1.1/5-1.1:1.4/0003:05FC:0231.0018/input/input55
  hid-generic 0003:05FC:0231.0018: input,hidraw2: USB HID v2.01 Device [Harman International Industries JBL Pebbles] on usb-0000:67:00.3-1.1/input4

Signed-off-by: Rong Zhang <i@rong.moe>
Link: https://patch.msgid.link/20260504-uac-jbl-pebbles-v1-1-c888d592a286@rong.moe
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-05-04 17:47:06 +02:00
2026-01-26 19:07:09 -08:00
2022-09-28 09:02:20 +02:00
2025-02-19 14:53:27 -07:00
2026-04-26 14:19:00 -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
Description
No description provided
Readme 3.5 GiB
Languages
C 97%
Assembly 1%
Shell 0.6%
Rust 0.5%
Python 0.4%
Other 0.3%