From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756426AbaDKJJn (ORCPT ); Fri, 11 Apr 2014 05:09:43 -0400 Received: from top.free-electrons.com ([176.31.233.9]:44548 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755858AbaDKJJk (ORCPT ); Fri, 11 Apr 2014 05:09:40 -0400 Date: Fri, 11 Apr 2014 11:09:36 +0200 From: Antoine =?iso-8859-1?Q?T=E9nart?= To: Andrew Lunn Cc: sebastian.hesselbarth@gmail.com, linus.walleij@linaro.org, zmxu@marvell.com, jszhang@marvell.com, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, alexandre.belloni@free-electrons.com, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH RESEND 5/5] ARM: dts: berlin: add the pinctrl node and muxing setup for uarts Message-ID: <20140411090936.GC20147@kwain> References: <1397135274-10764-1-git-send-email-antoine.tenart@free-electrons.com> <1397135274-10764-6-git-send-email-antoine.tenart@free-electrons.com> <20140411081859.GL10240@lunn.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20140411081859.GL10240@lunn.ch> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Andrew, On Fri, Apr 11, 2014 at 10:18:59AM +0200, Andrew Lunn wrote: > On Thu, Apr 10, 2014 at 03:07:54PM +0200, Antoine Ténart wrote: > > The uart0 pinmux configuration is in the dtsi because uart0 will always > > use uart0-pmux to work, no other possibility. Same thing for uart1. > > > > Signed-off-by: Antoine Ténart > > --- > > arch/arm/boot/dts/berlin2.dtsi | 20 ++++++++++++++++++++ > > arch/arm/boot/dts/berlin2cd.dtsi | 13 +++++++++++++ > > arch/arm/boot/dts/berlin2q.dtsi | 20 ++++++++++++++++++++ > > 3 files changed, 53 insertions(+) > > > > diff --git a/arch/arm/boot/dts/berlin2.dtsi b/arch/arm/boot/dts/berlin2.dtsi > > index 56a1af2f1052..43eb90c36050 100644 > > --- a/arch/arm/boot/dts/berlin2.dtsi > > +++ b/arch/arm/boot/dts/berlin2.dtsi > > @@ -176,6 +176,22 @@ > > }; > > }; > > > > + pinctrl: pinctrl@0 { > > + compatible = "marvell,berlin2-pinctrl"; > > + reg = <0xea0000 0x08>, <0xfc0000 0x44>; > > + reg-names = "global_base", "apb_base"; > > + > > + uart0_pmux: uart0-pmux { > > + berlin,group = "GSM4"; > > + berlin,function = <0>; > > + }; > > + > > + uart1_pmux: uart1-pmux { > > + berlin,group = "GSM5"; > > + berlin,function = <1>; > > Hi Antoine > > This very much looks like black magic. > > I assume the data sheet is not available? So i think you need to > document all possible combinations of values of group and function. > Maybe you can add a file in > > arch/arm/boot/dts/include/dt-bindings/pinctrl/ > > with something like > > #define GSM4_UART0 0 > #define GSM5_UART1 1 > #define GSM12_UART0 1 > #define GSM12_IrDA0 1 > #define GSM12_GPIO 2 Groups' functions are not the same between BG2/BG2CD and BG2Q so multiple headers would be needed which may not be a good thing. Some platforms use black magic, and we can find a pinmux configuration for OMAP looking like: 0x128 (PIN_INPUT_PULLUP | MUX_MODE0) Weel, we could explicitly define the functions in the driver itself and use in the dt something like: berlin,group = "GSM4"; berlin,function = "uart0"; This is what's done on the sunxi's pinctrl. Antoine -- Antoine Ténart, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com