https://srikar.tech/tags/uefi/Recent content in Uefi on Epoch101HugoenSat, 23 May 2026 00:00:00 +0000https://srikar.tech/blog/acpi-uefi-journey/Sat, 23 May 2026 00:00:00 +0000https://srikar.tech/blog/acpi-uefi-journey/<p>It&rsquo;s been a while since I blogged, and I thought this was cool enough to share.</p> <p>After using my <a href="https://srikar.tech/blog/new-laptop" >ThinkPad T14</a> for a while, I noticed that the LED above the power button (which doubles as the fingerprint sensor) can change colors - green and orange - in addition to the default white. I observed this during fingerprint registration and authentication on Windows, where it shows the scanner status:</p> <ol> <li><strong>White</strong> - default power indicator when the fingerprint scanner is not in use.</li> <li><strong>Green</strong> - sensor is ready and actively waiting for your finger.</li> <li><strong>3 orange blinks</strong> - if: <ul> <li>the fingerprint is not recognized during login, or</li> <li>the finger needs to be repositioned during registration.</li> </ul> </li> </ol> <p>None of this happens on Arch Linux. I wanted to understand why, and ideally fix it. I also noticed a second issue: the microphone mute LED stays on permanently, regardless of whether the microphone is actually muted. I suspected both problems might share a common cause.</p>