From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: Re: [PATCH 1/3] backlight: Allow drivers to update the core, and generate events on changes Date: Tue, 14 Jul 2009 14:21:52 +0100 Message-ID: <20090714132152.GA22521@srcf.ucam.org> References: <1247517685-7719-1-git-send-email-mjg@redhat.com> <20090714103006.GA19866@khazad-dum.debian.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from cavan.codon.org.uk ([93.93.128.6]:49499 "EHLO cavan.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752468AbZGNNVy (ORCPT ); Tue, 14 Jul 2009 09:21:54 -0400 Content-Disposition: inline In-Reply-To: <20090714103006.GA19866@khazad-dum.debian.net> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Henrique de Moraes Holschuh Cc: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, rpurdie@rpsys.net, lenb@kernel.org, rui.zhang@intel.com, corentincj@iksaif.net On Tue, Jul 14, 2009 at 07:30:07AM -0300, Henrique de Moraes Holschuh wrote: > On Mon, 13 Jul 2009, Matthew Garrett wrote: > > Certain hardware will send us events when the backlight brightness > > changes. Add a function to update the value in the core, and > > additionally send a uevent so that userspace can pop up appropriate > > UI. The uevents are flagged depending on whether the update originated > > in the kernel or from userspace, making it easier to only display UI > > at the appropriate time. > > Any reasons to not do it using poll() support (since sysfs has it)? Or at > least, do both poll and uevents? More code? It doesn't really seem necessary. > Other than that, I like the idea a lot. thinkpad-acpi will use this event > support. Good, that's one of the use-cases I wanted to deal with - but the hotkey mask stuff is complicated enough that I hadn't got round to touching that yet. The combination of this and the ALSA mixer code should get us full notification. -- Matthew Garrett | mjg59@srcf.ucam.org