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

From: Thomas Renninger
Date: Mon Dec 01 2008 - 06:55:38 EST

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.

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