Re: [ltp] IBM HDAPS Someone interested? (Accelerometer)

[Alejandro Bonilla]

Vojtech Pavlik wrote:

> On Sat, Jun 25, 2005 at 01:13:17PM -0500, Alejandro Bonilla wrote:
>
>  
>
> > I have a question here, how do you guys think that the head is parked, 
> > is it done by the controller directly, which then sends the command to 
> > the HD to park the head, or this is done by the operating system in some 
> > kind of way?
> >
> > I think the OS or user space is too slow like to react to send a park 
> > command to the hard drive, so this most be done directly by the embedded 
> > controller, but still I think it needs some input from the OS, to 
> > initialize it's settings.
> >    
>
> The only way to park a drive is to send a command to it through the IDE
> interface. This can't be done by the controller itself, since the
> controller in the ThinkPad is a classic Intel ICH chip which only passes
> commands around.
>
> The OS is definitely fast enough for this kind of task, it's doable even
> in userspace, although not easy.
>
>  
>
> > i.e. after all, in windows you do have the settings in the software
> > for HDAPS, but it looks like it is _not_ managed by the operating
> > system at all if there is some type of action to  be taken. This is
> > also probably why HDAPS won't kick in until booted, and that is
> > because it needs to load its config setup by the software.
> >    
>
>  
>
> > This is what I think, please correct me if I'm saying something crazy.
> >    
>
> It is definitely all done by the windows kernel driver.
>
>  
OK, So if this is done by the user space then I think we can play more 
with it? I guess that we could do a type of hdparm -F or hdparm -S to 
spin down the drive or maybe there is a way to add feature to hdparm to 
park the drive itself.

Aside from what we should do when we get the data... How can we/us/I 
start checking and see if we can find any response from the embedded 
controller?

Do we have to backengineer everything, can we get anything of this from 
IBM-ACPI, or our only way to go here is see if IBM will do anything?

Thanks for all the answers. I really don't want to drop the topic, so 
that we can figure this one out.

.Alejandro
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