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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Intel - display brightness control not working with i915.fastboot=1"
href="https://bugs.freedesktop.org/show_bug.cgi?id=103781">103781</a>
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<th>Summary</th>
<td>Intel - display brightness control not working with i915.fastboot=1
</td>
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<th>Product</th>
<td>DRI
</td>
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<th>Version</th>
<td>XOrg git
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<th>Hardware</th>
<td>Other
</td>
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<th>OS</th>
<td>All
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<th>Status</th>
<td>NEW
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<th>Severity</th>
<td>normal
</td>
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<th>Priority</th>
<td>medium
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<th>Component</th>
<td>DRM/Intel
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<th>Assignee</th>
<td>intel-gfx-bugs@lists.freedesktop.org
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<th>Reporter</th>
<td>arthurborsboom@gmail.com
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<th>QA Contact</th>
<td>intel-gfx-bugs@lists.freedesktop.org
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<th>CC</th>
<td>intel-gfx-bugs@lists.freedesktop.org
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=135522" name="attach_135522" title="dmesg when booted with the fastboot flag">attachment 135522</a> <a href="attachment.cgi?id=135522&action=edit" title="dmesg when booted with the fastboot flag">[details]</a></span>
dmesg when booted with the fastboot flag
Hardware: Asus N751JK laptop, i7-4710HQ
OS: Arch Linux
Kernel: 4.13.11
Kernel module: i915
While reading through a news article on Phoronix.com, I decided to test an
upcoming kernel/driver feature: Intel display 'fastboot'.
This can be activated by the kernel option i915.fastboot=1
This indeed speeds up the boot process and reduces the flickering, but with a
side effect. Normally I use the Fn-buttons to change the brightness of the
(laptop) screen. This works fine without the fastboot kernel parameter.
This does not work anymore with the kernel parameter. It seems to be stuck at
maximum brightness. When I press the reduce brightness button multiple times,
the screen turns black. When I press then only 1 time the increase brightness
button, the screen is back on at maximum brightness.
dmesg when booted with the fastboot parameter is attached.
Is this misconfiguration, a bug or something else?
Do I need to provide more information and if so what?
Best regards,
Arthur Borsboom.</pre>
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