Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754644Ab2HUIvj (ORCPT ); Tue, 21 Aug 2012 04:51:39 -0400 Received: from hqemgate04.nvidia.com ([216.228.121.35]:11373 "EHLO hqemgate04.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754037Ab2HUIve (ORCPT ); Tue, 21 Aug 2012 04:51:34 -0400 X-PGP-Universal: processed; by hqnvupgp06.nvidia.com on Tue, 21 Aug 2012 01:51:32 -0700 From: Alex Courbot To: Thierry Reding CC: Tomi Valkeinen , Stephen Warren , Simon Glass , Grant Likely , Rob Herring , Mark Brown , Anton Vorontsov , David Woodhouse , Arnd Bergmann , Leela Krishna Amudala , "linux-tegra@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-fbdev@vger.kernel.org" , "devicetree-discuss@lists.ozlabs.org" , "linux-doc@vger.kernel.org" Subject: Re: [PATCH v4 1/3] Runtime Interpreted Power Sequences Date: Tue, 21 Aug 2012 17:53:27 +0900 Message-ID: <1860040.h1S5hbLDAH@percival> Organization: NVIDIA User-Agent: KMail/4.9 (Linux/3.4.9-1-ARCH; KDE/4.9.0; x86_64; ; ) In-Reply-To: <20120821083329.GA28992@avionic-0098.adnet.avionic-design.de> References: <1345097337-24170-1-git-send-email-acourbot@nvidia.com> <1562509.b0FYTUZ1D8@percival> <20120821083329.GA28992@avionic-0098.adnet.avionic-design.de> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1353 Lines: 28 On Tuesday 21 August 2012 16:33:30 Thierry Reding wrote: > I suppose power sequences aren't needed if you have a specific driver > for every panel out there. However that also means that you'd have to > write drivers for literally every panel that requires support. In the > end this will just result in discussion down the road how the common > functionality can be refactored and we may end up with power sequences > again. > > Also as you mentioned, power sequences are useful for a number of other > use-cases. Without power sequences you'll have to potentially create > extra frameworks tha reimplement parts of the power sequence code for > their specific hardware needs. Yes, I can imagine what a mess it would become it we had one driver for every panel out there which sole purpose would be to define power sequences over more generic drivers. That reassures me about the usefulness of this work. Another (small) benefit of power sequences over specific drivers is that being defined in the DT, they would allow an old kernel to operate a newer device if the base driver is the same. Alex. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/