Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756001AbaJaIRO (ORCPT ); Fri, 31 Oct 2014 04:17:14 -0400 Received: from mail-ig0-f179.google.com ([209.85.213.179]:43527 "EHLO mail-ig0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751384AbaJaIRM convert rfc822-to-8bit (ORCPT ); Fri, 31 Oct 2014 04:17:12 -0400 MIME-Version: 1.0 In-Reply-To: <5cf5e2e5cd154992b2896b98988a409a@BN1BFFO11FD007.protection.gbl> References: <1413479495-14206-1-git-send-email-soren.brinkmann@xilinx.com> <1413479495-14206-9-git-send-email-soren.brinkmann@xilinx.com> <5cf5e2e5cd154992b2896b98988a409a@BN1BFFO11FD007.protection.gbl> Date: Fri, 31 Oct 2014 09:17:11 +0100 Message-ID: Subject: Re: [PATCH RFC v2 8/8] ARM: zynq: DT: Add pinctrl information From: Linus Walleij To: =?UTF-8?Q?S=C3=B6ren_Brinkmann?= Cc: Michal Simek , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Steffen Trumtrar Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 28, 2014 at 5:03 PM, Sören Brinkmann wrote: > On Tue, 2014-10-28 at 04:05PM +0100, Linus Walleij wrote: >> On Thu, Oct 16, 2014 at 7:11 PM, Soren Brinkmann >> wrote: >> >> > Add pinctrl descriptions to the zc702 and zc706 device trees. >> > >> > Signed-off-by: Soren Brinkmann >> >> (...) >> > +&pinctrl0 { >> > + pinctrl_can0_default: pinctrl-can0-default { >> > + common { >> > + function = "can0"; >> > + groups = "can0_9_grp"; >> > + bias-pull-up = <0>; >> >> No. If you want pull-up, just use >> bias-pull-up; >> >> If you want to disable pull-up, use >> bias-disable; > > But bias-disable also disables high-impedance. That doesn't work for me, > I think. Hm. Some sequencing problem right? Like you count on bias-high-impdedance being set in some other state? I think each state should be self-contained, so you set all the stuff you need in a state, do not rely on things coming in pre-set from another state. So in this case just set bias-high-impedance; then and if the state does not have bias-pull-up, *always* disable it in the driver. >> >> > + slew-rate = <0>; >> >> If this measure is any kind of time unit, this is against the laws of nature. > > It's not. As the bindings say, the argument is driver specific. Okay then. >> > + rx { >> > + pins = "MIO46"; >> > + bias-high-impedance = <1>; >> >> Just >> bias-high-impedance; > > Same problem as I have above. To allow all permutations of pull-up and > tri-state I can't just have a single disable-bias property. Again it seems to be a sequencing problem. And device tree is not good at sequences, therefore all states should be self-contained. Yours, Linus Walleij -- 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/