From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751710Ab3FNJS2 (ORCPT ); Fri, 14 Jun 2013 05:18:28 -0400 Received: from gloria.sntech.de ([95.129.55.99]:59249 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750970Ab3FNJS1 (ORCPT ); Fri, 14 Jun 2013 05:18:27 -0400 From: Heiko =?iso-8859-1?q?St=FCbner?= To: Laurent Pinchart Subject: Re: [PATCH 1/2] pinctrl: add function to parse generic pinconfig properties from a dt node Date: Fri, 14 Jun 2013 11:18:22 +0200 User-Agent: KMail/1.13.7 (Linux/3.2.0-3-686-pae; KDE/4.8.4; i686; ; ) Cc: linux-arm-kernel@lists.infradead.org, Linus Walleij , James Hogan , "linux-kernel@vger.kernel.org" , Patrice Chotard References: <201306102139.32444.heiko@sntech.de> <1862891.4yIecp615h@avalon> In-Reply-To: <1862891.4yIecp615h@avalon> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit Message-Id: <201306141118.22663.heiko@sntech.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Freitag, 14. Juni 2013, 01:53:49 schrieb Laurent Pinchart: > Hi Linus, > > On Thursday 13 June 2013 17:36:00 Linus Walleij wrote: > > On Thu, Jun 13, 2013 at 5:23 PM, Heiko Stübner wrote: > > >> Ok, I'll see that I get this fixed :-) > > > > > > Hmm ... what is the meaning of the argument of bias-disable and > > > bias-high- impedance, as the kernel-doc in pinconf-generic.h does not > > > tell? > > > > I think those arguments are N/A, ignored, doesn't matter. > > If these options were typed, they would be bool. > > > > Please improve documentation if you can... sorry for all the > > rough edges. > > > > > bias-bus-hold ignores its argument and we already clarified that the > > > pull-* do have != 0 or 0 argument. > > > > I think in the DT binding, both these forms: > > > > bias-pull-up; > > bias-pull-up = <150000>; > > > > Should be allowed. > > > > So when parsing, you first check if it exists, then if there > > is an argument, if there is no value supplied, just set it > > to 1, as that is clearly != 0... > > What's the expected way to disable pull-ups in DT ? Should it be > 'bias-pull-up = <0>;' or 'bias-disable;' ? According to the kernedoc I think both are valid and should be handled. Using bias-disable is more descriptive but would also include disabling a "high- impedance" or "bus-hold" bias (if supported by the hardware). Personally, for my rockchip stuff I go with using the "bias-pull-pin-default" <-> "bias-disable".