The Mute LED That Wouldn't Light: Chasing a Reddit Hack Into a Kernel Patch

说明与用途

问题：HP Omen 笔记本的静音 LED 未点亮。解决方案：在 Realtek ALC245 驱动中添加 PCI 修饰符，自动在静音状态下切换 LED。补丁已合并到内核，并在另一台 HP 笔记本上也修复了类似问题。

问题

The mute LED on an HP Omen laptop did not light when the speakers were muted, despite the mute function working correctly.

结果

A single PCI quirk table entry in the Linux kernel driver for Realtek ALC245 codecs restored mute LED functionality on HP laptops, eliminating the need for manual userspace hacks.

工作流

• 1. Verify hardware works on Windows to rule out hardware failure.
• 2. Use evtest to confirm mute key events and audio muting.
• 3. Check /sys/class/leds for LED device – none found.
• 4. Identify codec via /proc/asound/card*/codec* (Realtek ALC245).
• 5. Locate relevant driver file (alc269.c) and search for SND_PCI_QUIRK entries.
• 6. Confirm LED control via hda-verb: coefficient 0x0b, values 0x7778 (on) and 0x7774 (off).
• 7. Test manual writes to verify LED control.
• 8. Choose correct quirk macro (V1) and add entry: SND_PCI_QUIRK(0x103c,0x8ba9,"HP Omen 16-wd0xxx",ALC245_FIXUP_HP_MUTE_LED_V1_COEFBIT).
• 9. Build kernel, reboot, verify LED works on mute.
• 10. Submit patch to kernel maintainers; patch applied.
• 11. Patch later used to fix similar issue on HP Victus laptop.
• 12. Document process and lessons learned.

证据

The fix itself is simple and genuinely nothing to look at.

来源

The maintainer Takashi Iwai applied it.

来源