From mboxrd@z Thu Jan  1 00:00:00 1970
From: Kuninori Morimoto <kuninori.morimoto.gx@gmail.com>
Date: Mon, 06 Jan 2014 00:39:14 +0000
Subject: Re: [PATCH 3/3] ARM: shmobile: Koelsch: Add QSPI support
Message-Id: <871u0mkkpg.wl%kuninori.morimoto.gx@gmail.com>
List-Id: <linux-sh.vger.kernel.org>
References: <1388763256-25851-1-git-send-email-geert@linux-m68k.org>
 <1388763256-25851-4-git-send-email-geert@linux-m68k.org>
 <52C6EAA7.7050200@cogentembedded.com>
 <CAMuHMdVzawC2ccXCwyLSe7u0Uaa0qpLwaO+3dqQiSrmOcGdTCA@mail.gmail.com>
In-Reply-To: <CAMuHMdVzawC2ccXCwyLSe7u0Uaa0qpLwaO+3dqQiSrmOcGdTCA@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
To: linux-arm-kernel@lists.infradead.org

Hi

> <sergei.shtylyov@cogentembedded.com> wrote:
> >> +       platform_device_register_resndata(&platform_bus, "qspi", 0,
> >
> >    As I understood, there's single QSPI controller, so why you pass 0, and
> > not -1 here?
> 
> Indeed, there's only a single QSPI instance.
> However, I choose to use "0" for consistency with Lager.
> Mach-shmobile seems to use a mix of 0 and -1.
> 
> If the maintainer prefers -1, I can change that.

In SPI driver case, spi master will use dynamic 
bus_num value if ID was -1 (in spi_register_master()).
Then, slave device can't be detected.
So, ID = 0 is reasonable even though single QSPI.