From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1751784AbbCVNEF (ORCPT <rfc822;w@1wt.eu>);
	Sun, 22 Mar 2015 09:04:05 -0400
Received: from mail-wg0-f41.google.com ([74.125.82.41]:33978 "EHLO
	mail-wg0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751661AbbCVNEB (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Sun, 22 Mar 2015 09:04:01 -0400
Message-ID: <550EBDBC.9000903@gmail.com>
Date: Sun, 22 Mar 2015 14:03:56 +0100
From: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0
To: Wolfram Sang <wsa@the-dreams.de>
CC: Stephen Warren <swarren@wwwdotorg.org>,
        Jason Cooper <jason@lakedaemon.net>, Andrew Lunn <andrew@lunn.ch>,
        Gregory Clement <gregory.clement@free-electrons.com>,
        Gabriel Dobato <dobatog@gmail.com>, linux-i2c@vger.kernel.org,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 1/4] i2c: mux-pinctrl: Rework to honor disabled child
 nodes
References: <1425903665-19343-1-git-send-email-sebastian.hesselbarth@gmail.com> <20150318123012.GA3580@katana> <55097C46.9010605@gmail.com> <20150318140037.GE3580@katana> <550A05E5.3050100@gmail.com> <20150319100944.GA914@katana> <550AEF9D.6090307@wwwdotorg.org> <20150319160208.GF7657@katana> <550B3725.10209@gmail.com> <20150320101925.GC2071@katana> <20150321210028.GA1078@katana>
In-Reply-To: <20150321210028.GA1078@katana>
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 21.03.2015 22:00, Wolfram Sang wrote:
>>> I guess what you want to have is that i2c_add_adapter() is not called
>>> for the disabled case, right?
>>
>> I think that makes sense.
>
> But maybe we should just start simple and keep calling i2c_add_adapter()
> for the disabled case. We will just skip probing devices on the bus.
> Would that help the issue you were originally trying to solve?

It is not about probing devices on the mux sub-busses, I'd expect no
devices on the optional sub-busses in DT on boards where those pins
are not used as i2c.

The idea was to hide those busses completely in particular from
userspace on boards where they'll never be available.

If modifying i2c-mux-pinctrl to respect the sub-bus status property is
such a big issue, I'd rather leave the driver as is and expose all
sub-busses to userspace.

Sebastian