Received-SPF: pass (google.com: domain of linux-kernel+bounces-133063-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) client-ip=2604:1380:45e3:2400::1;
Precedence: bulk
MIME-Version: 1.0
References: <cover.1712207606.git.ysato@users.sourceforge.jp> <dac98a697c8e850054f984964af62a209f241c83.1712207606.git.ysato@users.sourceforge.jp>
In-Reply-To: <dac98a697c8e850054f984964af62a209f241c83.1712207606.git.ysato@users.sourceforge.jp>
From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: Fri, 5 Apr 2024 15:25:31 +0200
Message-ID: <CAMuHMdVRLwv1c+L0DP_jRJh6_=-oTQJWOcYCzYqowW8tyOJK2A@mail.gmail.com>
Subject: Re: [RESEND v7 23/37] dt-bindings: display: sm501 register definition helper
To: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: linux-sh@vger.kernel.org, Damien Le Moal <dlemoal@kernel.org>, 
	Niklas Cassel <cassel@kernel.org>, Rob Herring <robh@kernel.org>, 
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Conor Dooley <conor+dt@kernel.org>, 
	Michael Turquette <mturquette@baylibre.com>, Stephen Boyd <sboyd@kernel.org>, 
	David Airlie <airlied@gmail.com>, Daniel Vetter <daniel@ffwll.ch>, 
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>, Maxime Ripard <mripard@kernel.org>, 
	Thomas Zimmermann <tzimmermann@suse.de>, Thomas Gleixner <tglx@linutronix.de>, 
	Bjorn Helgaas <bhelgaas@google.com>, Lorenzo Pieralisi <lpieralisi@kernel.org>, 
	=?UTF-8?Q?Krzysztof_Wilczy=C5=84ski?= <kw@linux.com>, 
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Jiri Slaby <jirislaby@kernel.org>, 
	Magnus Damm <magnus.damm@gmail.com>, Daniel Lezcano <daniel.lezcano@linaro.org>, 
	Rich Felker <dalias@libc.org>, John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>, 
	Lee Jones <lee@kernel.org>, Helge Deller <deller@gmx.de>, 
	Heiko Stuebner <heiko.stuebner@cherry.de>, Shawn Guo <shawnguo@kernel.org>, 
	Sebastian Reichel <sre@kernel.org>, Chris Morgan <macromorgan@hotmail.com>, 
	Linus Walleij <linus.walleij@linaro.org>, Arnd Bergmann <arnd@arndb.de>, 
	David Rientjes <rientjes@google.com>, Hyeonggon Yoo <42.hyeyoo@gmail.com>, 
	Vlastimil Babka <vbabka@suse.cz>, Baoquan He <bhe@redhat.com>, 
	Andrew Morton <akpm@linux-foundation.org>, Guenter Roeck <linux@roeck-us.net>, 
	Kefeng Wang <wangkefeng.wang@huawei.com>, Stephen Rothwell <sfr@canb.auug.org.au>, 
	Javier Martinez Canillas <javierm@redhat.com>, Guo Ren <guoren@kernel.org>, 
	Azeem Shaikh <azeemshaikh38@gmail.com>, Max Filippov <jcmvbkbc@gmail.com>, 
	Jonathan Corbet <corbet@lwn.net>, Jacky Huang <ychuang3@nuvoton.com>, 
	Herve Codina <herve.codina@bootlin.com>, 
	Manikanta Guntupalli <manikanta.guntupalli@amd.com>, Anup Patel <apatel@ventanamicro.com>, 
	Biju Das <biju.das.jz@bp.renesas.com>, 
	=?UTF-8?Q?Uwe_Kleine=2DK=C3=B6nig?= <u.kleine-koenig@pengutronix.de>, 
	Sam Ravnborg <sam@ravnborg.org>, Sergey Shtylyov <s.shtylyov@omp.ru>, 
	Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>, linux-ide@vger.kernel.org, 
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, 
	linux-renesas-soc@vger.kernel.org, linux-clk@vger.kernel.org, 
	dri-devel@lists.freedesktop.org, linux-pci@vger.kernel.org, 
	linux-serial@vger.kernel.org, linux-fbdev@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

Hi Sato-san,

Thanks for your patch!

On Thu, Apr 4, 2024 at 7:15=E2=80=AFAM Yoshinori Sato
<ysato@users.sourceforge.jp> wrote:
> Miscellaneous Timing and Miscellaneous Control registers definition.

Please do not put raw register value definitions into DT bindings.

> Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>

> --- /dev/null
> +++ b/include/dt-bindings/display/sm501.h

> +/* Miscellaneous timing */
> +#define SM501_MISC_TIMING_EX_HOLD_0    0
> +#define SM501_MISC_TIMING_EX_HOLD_16   1
> +#define SM501_MISC_TIMING_EX_HOLD_32   2
> +#define SM501_MISC_TIMING_EX_HOLD_48   3
> +#define SM501_MISC_TIMING_EX_HOLD_64   4
> +#define SM501_MISC_TIMING_EX_HOLD_80   5
> +#define SM501_MISC_TIMING_EX_HOLD_96   6
> +#define SM501_MISC_TIMING_EX_HOLD_112  7
> +#define SM501_MISC_TIMING_EX_HOLD_128  8
> +#define SM501_MISC_TIMING_EX_HOLD_144  9
> +#define SM501_MISC_TIMING_EX_HOLD_160  10
> +#define SM501_MISC_TIMING_EX_HOLD_176  11
> +#define SM501_MISC_TIMING_EX_HOLD_192  12
> +#define SM501_MISC_TIMING_EX_HOLD_208  13
> +#define SM501_MISC_TIMING_EX_HOLD_224  14
> +#define SM501_MISC_TIMING_EX_HOLD_240  15

E.g. these are used by the (not very descriptive) "ex" property:

     ex:
       $ref: /schemas/types.yaml#/definitions/uint32
       description: Extend bus holding time.

Please instead use an enum for the actual holding time ([ 0, 16, 32,
..]) in the DT bindings, and convert from actual holding time to
register value in the driver.

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. Bu=
t
when I'm talking to journalists I just say "programmer" or something like t=
hat.
                                -- Linus Torvalds