Re: [PATCH] Request driver inclusion - acer aspire one fan control

From: Andreas Mohr
Date: Thu Jun 18 2009 - 09:55:08 EST


Hi,

On Thu, Jun 18, 2009 at 03:31:35PM +0200, Peter Feuerer wrote:
> You are partly right, setting the fan to auto in
> "acerhdf_revert_to_bios_mode" can be removed, as this is done by the
> thermal layer when calling "acerhdf_set_cur_state" with
> disable_kernelmode=1.

No, it was done _specifically_ this way to make sure that _exactly when_
switching away from kernel mode FAN_AUTO _always_ (by asking people to
always call this central function) gets set, too.
I don't want to depend on a separate, _uncontrollable_ entity
(thermal layer function) to have to run sometime later
in order to set the fan to FAN_AUTO (IOW, BIOS-controlled mode) accordingly.
_Of course_ this FAN_AUTO call is redundant in _most_ cases, but very
intentionally so. Anything else would be woefully unsafe (with a fan
remaining in FAN_OFF position until machine meltdown).

Andreas Mohr
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/