inverted brightness for HP notebook

[Jani Nikula]

On Wed, 17 Jun 2015, Max Manheimer <stiltskin at ymail.com> wrote:
> Hi,
>
> Jani Nikula <jani.nikula <at> linux.intel.com> writes:
>
>> On Thu, 13 Nov 2014, olivier.fambon <at> free.fr wrote:
>
>>> $ lspci | grep VGA
>>> 00:02.0 VGA compatible controller: Intel Corporation ValleyView Gen7 (rev 0e)
>
>>> $ sudo lspci -v -s 00:02
>>> 00:02.0 VGA compatible controller: Intel Corporation ValleyView Gen7 (rev
> 0e) (prog-if 00 [VGA controller])
>>> 	Subsystem: Hewlett-Packard Company Device 2213
>>> 	Flags: bus master, fast devsel, latency 0, IRQ 107
>>> 	Memory at 90000000 (32-bit, non-prefetchable) [size=4M]
>>> 	Memory at 80000000 (32-bit, prefetchable) [size=256M]
>>> 	I/O ports at 3050 [size=8]
>>> 	Expansion ROM at <unassigned> [disabled]
>>> 	Capabilities: [d0] Power Management version 2
>>> 	Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
>>> 	Capabilities: [b0] Vendor Specific Information: Len=07 <?>
>>> 	Kernel driver in use: i915
>
>>> => requires the following to make brightness control keys work as expected
>
>>> $ cat /etc/modprobe.d/i915.conf 
>>> options i915 invert_brightness=1
>
> As there's a specific broadwell i915 module, you have to adapt as follows:
>
> options i915_bdw invert_brightness=1
>  
>> I highly doubt this. This might be true for some gen4 models, but not
>> Valleyview.
>
> The above mentioned i915_bdw option fixes the backlight inversion on my HP
> 250 G3 (same lspci output as in original post)

i915_bdw is an Ubuntu thing, upstream has nothing to do with it. But I'm
surprised they'd use i915_bdw for a Baytrail/Valleyview.

If you can reproduce with the upstream driver, please file a bug at [1].

BR,
Jani.


[1] https://bugs.freedesktop.org/enter_bug.cgi?product=DRI&component=DRM/Intel


-- 
Jani Nikula, Intel Open Source Technology Center