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 S1752683AbcGMPGW (ORCPT <rfc822;w@1wt.eu>);
	Wed, 13 Jul 2016 11:06:22 -0400
Received: from mail-oi0-f45.google.com ([209.85.218.45]:34961 "EHLO
	mail-oi0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751092AbcGMPGM convert rfc822-to-8bit (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Wed, 13 Jul 2016 11:06:12 -0400
MIME-Version: 1.0
In-Reply-To: <578654A7.2020909@samsung.com>
References: <1468326921-26485-1-git-send-email-zajec5@gmail.com>
 <1468413734-9569-1-git-send-email-zajec5@gmail.com> <1468413734-9569-3-git-send-email-zajec5@gmail.com>
 <578654A7.2020909@samsung.com>
From: =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= <zajec5@gmail.com>
Date: Wed, 13 Jul 2016 17:05:32 +0200
Message-ID: <CACna6rwgjZoPiU1Qo_4PU35ZuovN-cBe5kVZpUQQPDUf1xQyLA@mail.gmail.com>
Subject: Re: [PATCH V2 PROOF OF CONCEPT 2/1] trigger: ledtrig-usbport: read
 initial state from DT
To: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
        "open list:LED SUBSYSTEM" <linux-leds@vger.kernel.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        Richard Purdie <rpurdie@rpsys.net>,
        open list <linux-kernel@vger.kernel.org>,
        Rob Herring <robh+dt@kernel.org>, Mark Rutland <Mark.Rutland@arm.com>,
        Felipe Balbi <balbi@kernel.org>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8BIT
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 13 July 2016 at 16:48, Jacek Anaszewski <j.anaszewski@samsung.com> wrote:
> On 07/13/2016 02:42 PM, Rafał Miłecki wrote:
>>
>> This allows specifying USB ports that should be observed by a trigger
>> right after activating it. Example:
>>
>> usb {
>>         gpios = <&gpio 0 GPIO_ACTIVE_HIGH>;
>>         linux,default-trigger = "usbport";
>>         usb-controllers = <&ohci>, <&ehci>, <&xhci USB_HCD_SHARED>;
>>         usb-ports = "1", "1", "1";
>
>
> Port is a numerical value, right?
> Wouldn't it be better to define it as an array of integers?
>
> e.g.: usb-ports = <1>. <1>, <1>;

Not always. Let me quote this part of "usbport" documentation:

> This also allows handling devices with internal hubs (when root hub's port has
> always a device (hub) connected). User can simply specify specify internal hub
> ports then (e.g. 1-1.1, 1-1.2, etc.).

In such case we'd need usb-ports = "1.1", "1.2";

Anyway, there is a discussion ongoing in:
[PATCH V2 0/1] usb: add HCD providers
so let's see if someone will have a better idea for referencing USB
ports inside DT.