From mboxrd@z Thu Jan  1 00:00:00 1970
From: arnd@arndb.de (Arnd Bergmann)
Date: Wed, 09 Nov 2016 22:40:14 +0100
Subject: [PATCH v1 03/11] drivers: soc: hisi: Add support for Hisilicon
 Djtag driver
In-Reply-To: <5822A5F6.9040806@gmail.com>
References: <1478101374-18778-1-git-send-email-anurup.m@huawei.com>
 <4657586.c5MJoh65Ux@wuerfel> <5822A5F6.9040806@gmail.com>
Message-ID: <4812554.ng09YGQfZ9@wuerfel>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Wednesday, November 9, 2016 9:58:38 AM CET Anurup M wrote:
> 
> > I also see that the compatible strings have the version included in
> > them, and you can probably drop them by requiring them only in the
> > fallback:
> >
> >       compatible = "hisilicon,hip05-cpu-djtag", "hisilicon,djtag-v1";
> >       compatible = "hisilicon,hip05-io-djtag", "hisilicon,djtag-v1";
> >       compatible = "hisilicon,hip06-cpu-djtag", "hisilicon,djtag-v1";
> >       compatible = "hisilicon,hip06-io-djtag", "hisilicon,djtag-v2";
> >       compatible = "hisilicon,hip07-cpu-djtag", "hisilicon,djtag-v2";
> >       compatible = "hisilicon,hip07-io-djtag", "hisilicon,djtag-v2";
> >
> > We want to have the first entry be as specific as possible, but
> > the last (second) entry is the one that can be used by the driver
> > for matching. When a future hip08/hip09/... chip uses an existing
> > interface, you then don't have to update the driver.
> Thanks. I had a similar thought on this. So as I have the version string 
> in the
> second entry "-v(1/2)".
> I can use it in driver for matching. So i think  I will change it as below.
> Please correct me if my understanding is wrong.
> 
>   static const struct of_device_id djtag_of_match[] = {
> -       /* for hip05(D02) cpu die */
> -       { .compatible = "hisilicon,hip05-cpu-djtag-v1",
> +       /* for hisi djtag-v1 cpu die */
> +       { .compatible = "hisilicon,hisi-cpu-djtag-v1",
>                  .data = djtag_readwrite_v1 },
> -       /* for hip05(D02) io die */
> -       { .compatible = "hisilicon,hip05-io-djtag-v1",
> +       /* for hisi djtag-v1 io die */
> +       { .compatible = "hisilicon,hisi-io-djtag-v1",

>>From the code it looks like "hisilicon,hisi-io-djtag-v1" and
"hisilicon,hisi-cpu-djtag-v1" have the same register-level interface,
so we just need one compatible string for them to match the driver.

	Arnd