Re: [PATCH 6/6] dt-bindings: spi: Document Renesas SPIBSC bindings

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Chris Brandt <chris.brandt@renesas.com>
Cc: Mark Brown <broonie@kernel.org>, Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Geert Uytterhoeven <geert+renesas@glider.be>,
	Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>,
	linux-spi <linux-spi@vger.kernel.org>,
	"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
	<devicetree@vger.kernel.org>,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
	linux-clk <linux-clk@vger.kernel.org>,
	Mason Yang <masonccyang@mxic.com.tw>,
	Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Subject: Re: [PATCH 6/6] dt-bindings: spi: Document Renesas SPIBSC bindings
Date: Tue, 3 Dec 2019 19:57:21 +0100
Message-ID: <CAMuHMdVBYpuoK7hcyNLK-mAdpTQz3ohTGXuYdFPHdpU5RoPr6Q@mail.gmail.com> (raw)
In-Reply-To: <20191203034519.5640-7-chris.brandt@renesas.com>

Hi Chris,

On Tue, Dec 3, 2019 at 4:47 AM Chris Brandt <chris.brandt@renesas.com> wrote:
> Document the bindings used by the Renesas SPI bus space controller.
>
> Signed-off-by: Chris Brandt <chris.brandt@renesas.com>

Thanks for your patch!

> --- /dev/null
> +++ b/Documentation/devicetree/bindings/spi/spi-renesas-spibsc.txt

Checkpatch.pl says:
WARNING: DT bindings should be in DT schema format. See:
Documentation/devicetree/writing-schema.rst

> @@ -0,0 +1,48 @@
> +Renesas SPI Bus Space Controller (SPIBSC) Device Tree Bindings
> +
> +Otherwise referred to as the "SPI Multi I/O Bus Controller" in SoC hardware
> +manuals. This controller was designed specifically for accessing SPI flash
> +devices.
> +
> +Required properties:
> +- compatible: should be an SoC-specific compatible value, followed by
> +               "renesas,spibsc" as a fallback.
> +               supported SoC-specific values are:
> +               "renesas,r7s72100-spibsc"       (RZ/A1)
> +               "renesas,r7s9210-spibsc"        (RZ/A2)

Is the fallback valid for RZ/A1, which has its own special match entry
in the driver?
Will it be valid for R-Car Gen3?
If not, you may want to drop it completely.

> +- reg: should contain three register areas:
> +       first for the base address of SPIBSC registers,
> +       second for the direct mapping read mode
> +- clocks: should contain the clock phandle/specifier pair for the module clock.
> +- power-domains: should contain the power domain phandle/specifier pair.
> +- #address-cells: should be 1
> +- #size-cells: should be 0
> +- flash: should be represented by a subnode of the SPIBSC node,
> +        its "compatible" property contains "jedec,spi-nor" if SPI is used.

What about the "mtd-rom" use for e.g. XIP?

interrupts? RZ/A2M seems to have an SPIBSC interrupt, RZ/A1 hasn't.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds