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From:   Baolin Wang <baolin.wang7@gmail.com>
Date:   Fri, 17 Apr 2020 09:20:59 +0800
Message-ID: <CADBw62pg6F4PiD=jJnrFDmaMN6yh76PSJ1=2_DZjwMJVQ+pFdQ@mail.gmail.com>
Subject: Re: [RFC PATCH v2 3/3] soc: sprd: Add Spreadtrum special bits
 updating support
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Lee Jones <lee.jones@linaro.org>, Mark Brown <broonie@kernel.org>,
        Orson Zhai <orsonzhai@gmail.com>,
        Lyra Zhang <zhang.lyra@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Thu, Apr 16, 2020 at 10:38 PM Arnd Bergmann <arnd@arndb.de> wrote:
>
> On Thu, Apr 16, 2020 at 3:49 PM Baolin Wang <baolin.wang7@gmail.com> wrote:
>
> >
> > OK, I think adding a Spreadtrum compatible string will be an easy and
> > clear way, so what about below sample code?
> >
> > DT:
> > ap_ahb_regs: syscon@20210000 {
> >          compatible = "sprd,sc9860-syscon", "syscon";
> >          reg = <0 0x20210000 0 0x10000>;
> > };
> >
> > /* The Spreadtrum syscon need register a real physical regmap bus with
> > new bits updating method. */
> > if (of_device_is_compatible(np, "sprd,sc9860-syscon") && syscon_phy_regmap_bus)
> >        regmap = regmap_init(NULL, syscon_phy_regmap_bus, base, &syscon_config);
> > else
> >        regmap = regmap_init_mmio(NULL, base, &syscon_config);
>
> Ok, sounds good. Maybe also define another compatible string that
> is more generic than "sprd,sc9860-syscon" (but less generic than
> "syscon") so you can still identify the chip specific syscon area if
> necessary, while not having to list each future chip individually.

OK.

>
> Something like
>
> compatible = "sprd,sc9860-syscon", "sprd,atomic-syscon", "syscon";
>
> Also I'd add an IS_ENABLED() check so it gets the 'else' path
> at compile-time when CONFIG_ARCH_SPRD is disabled.

Sure. Will do in next version. Thanks for your good suggestion.

-- 
Baolin Wang