2015-12-30 10:50 GMT+01:00 Marek Vasut <marex@xxxxxxx>:
> On Wednesday, December 30, 2015 at 10:43:02 AM, Mykola Dvornik wrote:
>> Hi Marek,
>>
>> Thanks for you prompt reply.
>>
>> The DSDT describes _ALI method:
>>
>> ...
>> Device (ALSD)
>> {
>> Name (_HID, "ACPI0008" /* Ambient Light Sensor Device */) //
>> _HID: Hardware ID
>> Method (_STA, 0, NotSerialized) // _STA: Status
>> {
>> If ((ALSE == 0x02))
>> {
>> Return (0x0B)
>> }
>>
>> Return (Zero)
>> }
>>
>> Method (_ALI, 0, NotSerialized) // _ALI: Ambient Light
>> Illuminance
>> {
>> Return (((LHIH << 0x08) | LLOW))
>> }
>> ...
>>
>> acpidump also shows _ALI method.
>>
>> But '/sys/bus/acpi/devices/ACPI0008:00' only contains:
>>
>> hid
>> modalias
>> path
>> power
>> status
>> subsystem
>> uevent
Hi,
looking at this portion of the ACPI table I can see that the
status of the ambient light sensor is controlled by a variable
(ALSE, which I guess stands for ALS Enabled).
If the output of /sys/bus/acpi/devices/ACPI0008:00/status is 0,
then the light sensor is disabled and must be somehow enabled.
When the sensor is enabled, the output of status should be 11. I
don't know what controls the value of ALSE, I think it's something
specific of your laptop.
Regards,
Gabriele
> OK, I don't have a machine with the ALS in it here, so I am CCing the list and
> a few more interested parties.
>
>> Regards,
>>
>> Mykola
>>
>> On Wed, Dec 30, 2015 at 9:52 AM, Marek Vasut <marex@xxxxxxx> wrote:
>> > On Wednesday, December 30, 2015 at 09:32:48 AM, Mykola Dvornik wrote:
>> >> Hi guys,
>> >>
>> >> I am writing to you because the acpi-als kernel module is not
>> >>
>> >> detecting
>> >>
>> >> ALS on Dell XPS 13 9343.
>> >>
>> >> The (decompiled) DSDT of the laptop is attached to this email.
>> >>
>> >> The ACPI0008 is present in the system with 'cat modalias':
>> >>
>> >> acpi:ACPI0008:
>> >>
>> >> but exposes no iio-related stuff.
>> >>
>> >> I am running Fedora 23 with kernel-4.2.8.
>> >>
>> >> Would you be so kind to look into this issue?
>> >
>> > Do you have the _ALI value in the ACPI0008 ? That's what's used to
>> > read out
>> > the illuminance and without it, the ALS driver won't report anything.
>> >
>> > Best regards,
>> > Marek Vasut
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