Re: Laptop shock detection and harddisk protection

[Austin Zhang <austin_zhang@linux.intel.com>]

On Wed, 2008-09-10 at 18:59 +0200, Tejun Heo wrote:

> 2. If we're gonna unify interface, how much can we unify the backend?
>    Some devices are based on polling, others interrupt.  For polling,
>    is it better to delegate the whole polling to userland or is it
>    better to do some of it in kernel (tp_smapi seems to be doing
>    this)?
Shock protection should be time-sensitive, if we put the whole polling 
into userland, will it be possible that the damage had happened before 
userland app can signal ATA idle command timely?

> 3. What about the userland daemon?  It would be best to have a unified
>    daemon which can handle all instead of one for hdaps and another
>    for hp (and so on).  If we can unify the interface, this will be
>    much easier.
> 
> Thanks.

Can this process "acceleration-detect --> inform ATA shock protect --> 
issue idle command" be done totally in kernel, avoiding to consume too 
many time for "acceleration-detect --> sysfs --> userland app --> sysfs 
--> inform ATA shock protect --> issue idle command" before HD was damaged? 
The userland daemon should be just a indicator (but of course it can pass 
params to driver) for the protection status rather than a judge.