Please help!: Keyboard backlight not working on my NP900X5N laptop <previous not accepted due to HTML encoding>

From: Jan Vlietland
Date: Wed Jan 02 2019 - 18:21:41 EST

Hi guys,

Sorry but still walking with this bug under my arm.

I can't find the right group to file the bug on bugzilla and also on freenode I cannot find the right group.

Please help!



On 01-01-19 13:48, Jan Vlietland wrote:
Hi all,

Greg K-H suggested to mail you guys.

I installed Linux 4.20.0-rc7 (downloaded, compiled and installed) on a Samsung NP900X5N laptop and have noticed 3 bugs. 2 of them I found in Bugzilla and replied on them (i915 and Nouveau issues). I am currently discussing them with an intel engineer.

On other bug I haven't found so therefore a mail directly to you guys as maintainers.

On my other machine, a Samsung NP900X4D (just bought it in the USA, 2017 model), the samsung-laptop.ko module is enabling the use of the keyboard backlight keys.

It is not working on my new machine NP900X5N. My samsung-laptop.ko driver isn't loading. If I try to load it manually it complains about 'no such device".

My Linux kernel is working in CSM mode. The module is still not loaded.

As it is weekend I did some more reading and debugging of the module. To my understanding the module checks the model and type of the laptop. The known models and types are stored in the struct:

static struct dmi_system_id __initdata samsung_dmi_table[]

I wondr if the NP900X5N notebook is included in this list.

With dmidecode -t chassis it shows:
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.

Handle 0x0003, DMI type 3, 22 bytes
Chassis Information
ÂÂÂÂÂÂÂ Type: Notebook
ÂÂÂÂÂÂÂ Lock: Not Present
ÂÂÂÂÂÂÂ Version: N/A
ÂÂÂÂÂÂÂ Serial Number: 0F4C91CJ900346
ÂÂÂÂÂÂÂ Asset Tag: No Asset Tag
ÂÂÂÂÂÂÂ Boot-up State: Safe
ÂÂÂÂÂÂÂ Power Supply State: Safe
ÂÂÂÂÂÂÂ Thermal State: Other
ÂÂÂÂÂÂÂ Security Status: None
ÂÂÂÂÂÂÂ OEM Information: 0x00000000
ÂÂÂÂÂÂÂ Height: Unspecified
ÂÂÂÂÂÂÂ Number Of Power Cords: 1
ÂÂÂÂÂÂÂ Contained Elements: 0
ÂÂÂÂÂÂÂ SKU Number: Chassis

If I use the -u flag. The notebook value is 0x0A, not 0x10!!!

Could that be the reason for not loading?

ÂÂÂÂÂÂÂ .matches = {

Maybe another reason could that that either the i915 and Nouveau modules are not working well. I get black screens with the i915 and MMIO faults with the nouveau driver. That is another issue that I need to tackle.

Oh happy new year :-)