From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lennart Poettering Subject: Re: [PATCH] misc,acpi,backlight: MSI S270 Laptop support Date: Wed, 4 Oct 2006 03:53:34 +0200 Message-ID: <20061004015333.GA6356@tango.0pointer.de> References: <20061003011056.GA28731@ecstasy.ring2.lan> <200610022227.10087.dtor@insightbb.com> <20061004012832.GA5171@tango.0pointer.de> <200610032137.29844.dtor@insightbb.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from tango.0pointer.de ([217.160.223.3]:19218 "EHLO tango.0pointer.de") by vger.kernel.org with ESMTP id S1030691AbWJDBxf (ORCPT ); Tue, 3 Oct 2006 21:53:35 -0400 Content-Disposition: inline In-Reply-To: <200610032137.29844.dtor@insightbb.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Dmitry Torokhov Cc: len.brown@intel.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org On Tue, 03.10.06 21:37, Dmitry Torokhov (dtor@insightbb.com) wrote: > > If auto_brightness is 2 we assume that the user doesn't want the > > module to fiddle with the automatic brightness control > > automatically. So we don't do it, neither when loading nor when > > unloading the module. However, if the user wants to fiddle with the > > setting through sysfs he may do so and we will not reset his changes > > when unloading the module. This allows the user to do something like > > this to disable the brightness control without having the the driver > > loaded the whole time: > > > > modprobe msi-laptop auto_brightness=2 && echo 0 > /sys/devices/platform/msi-laptop-pf/auto_brightness && modprobe -r msi-laptop > > > > If auto_brightness is 1 or 0, we do as requested but reset the control > > to the bootup default when unloading. (i.e. enable it again) > > Normally drivers clean up after themselves as if they were never loaded, > taht is why I questioned partial cleanup. Sure. But "normally" the user wouldn't bother to pass auto_brightness=2 to the module in which case we *do* "clean up" after ourselves and reenable automatic brightness control on module unload. The special behaviour when auto_brightness=2 is passed is merely a special feature for those who need it. It was useful to me and was trivial to implement, and hence I did it. Lennart -- Lennart Poettering; lennart [at] poettering [dot] net ICQ# 11060553; GPG 0x1A015CC4; http://0pointer.net/lennart/