Re: HP accelerometer: free fall detection working, testers wanted

From: Éric Piel
Date: Mon Dec 01 2008 - 07:03:23 EST

Thomas Renninger schreef:
> On Sunday 30 November 2008 23:16:29 Éric Piel wrote:
>> Pavel Machek schreef:
>>> Hi!
>>>>> I got free fall detection to work -- apparently BIOS does all the
>>>>> important stuff itself.
>>>>> Now... I'd like some testers. (Don't comment on code... yet. Yes, it
>>>>> has some issues).
>>>> Also, how do you try free fall? Did you try also with the lid
>>>> opened?
>>> With the lid opened, too, yes. I just took the machine, then tried to
>>> let go and catch it meter below that. (Of course I did not really let
>>> go, but released the grip and followed...)
>> Hi,
>> I've tested it. Mostly, it works. If I let it fall, it detects it. If I
>> repeat, it detects it again. If shake it, it doesn't detect any freefall
>> (good). However, for this to work on my laptop (2510p), after the device
>> is turned on, the AC must be unplugged and lid closed before it starts
>> working. It seems that that's only this specific state that triggers the
>> configuration of the sensor by the bios. Once setup, I can plug back and
>> open again the lid, the sensor keeps detecting the freefalls (until it's
>> turned off again).
>> So I think it's still necessary to explicitly set up the sensor. It's
>> just a matter of setting up the registers as the bios does. We should be
>> able to manage (just by dumping them once).
>> BTW, there were a couple of problems with the scripts. You have change
>> "/dev/misc" to "/dev/freefall" (which I also like more) but forgot to
>> update the driver itself.
>> For hp3dg, it couldn't find the led (not the same truncation of the name
>> of the led). Probably you could replace the name of the led by:
>> /sys/class/leds/*hddprotect*/
>> The led never turns off, because the sleep is slightly shorter than the
>> unload command.
>> Moreover, on my system I have neither /proc/acpi/button/lid/LID/state
>> nor /proc/acpi/ac_adapter/AC0/state ! I guess they could be replaced by
>> a clever use of /dev/input/eventX (contening Lid) and
>> /sys/class/power_supply/*/online
> These should still exist (bug?), as long as you do compile with ACPI_PROCFS
> (and load the ac, button modules).
> But there should also exist a sysfs replacement:
> gives an overview of what is converted and where it should pop up now.
Yes, I explicitly compiled my kernel without ACPI_PROCFS. This was just
to remind Pavel that his brand new script relies on deprecated
interfaces ;-)

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