From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D87502B9B7; Thu, 9 Oct 2025 18:21:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760034069; cv=none; b=XE7m3bXRHtmNmrLhFHgb77efP/nxC0XawSLHpUzEnzZWdgFQuk26qET8gk6aeks5ehMOgwlFdl7Rk+8usJc6wjOP6qTTUxyqekni+zBvLObgQVKHWuvsf6RAWYqj1ZB+ywFq065CPYcVnySgsOmki4xekKM2UEkE8q/4kq7aLNE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760034069; c=relaxed/simple; bh=gSU8W5D4kBW7HRmvXDO5mEeTlq8vT4Rj7qnh9fKuWsc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=hQhqk2Zn2whYLt7Jv15OCpHmpRTmhQdcjDPdYmjokYT9ShjjVF/3R0yaLXn3wSKIIGFROfJkMbWEnmBbtI8+8Fwq0eqF5vER2RJIqDI5iij0lY604svAEm3+jGcDn6+KQ/RwC2TDS0U3rp452li3+KjKKn4j1MlnYfLO/ltP+YU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=MHIkDUP8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="MHIkDUP8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3023DC4CEE7; Thu, 9 Oct 2025 18:21:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1760034067; bh=gSU8W5D4kBW7HRmvXDO5mEeTlq8vT4Rj7qnh9fKuWsc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=MHIkDUP8L1PxRA/oWJPqb0+xdtOgd6Cv0hkFUhfzjX963Uaq73ApP7JeaUXF65O9e ysw38t0EbeE1V2n/6itF9XDl8LbBFsb2EH0taFpB/2djmBnBoTCyxDbpzmgdHyFYcP aXQkyk3fOHuDgHq2z85I22XolPBpy4S2m/JixFojMjRRPF8yWczmM6BOnoVhAsr0Ub OycjLXvvfJ93Df/wglCnwldJOjkr4YNCc2U/i9ThK/tT4+iRHBUU0EpbSHngC8Z7D3 5PRafWTVx4F09M/lMsA+ifwsDyhkNfsOnYo+ILl7RTNltlKERFxLCoohw4Xh98cMI2 ff0UNX8hKmI/A== Date: Thu, 9 Oct 2025 19:21:00 +0100 From: Conor Dooley To: Frank Li Cc: maudspierings@gocontroll.com, Lee Jones , Daniel Thompson , Jingoo Han , Pavel Machek , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Helge Deller , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Liam Girdwood , Mark Brown , dri-devel@lists.freedesktop.org, linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fbdev@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v4 1/4] dt-bindings: backlight: Add max25014 bindings Message-ID: <20251009-overjoyed-unpopular-54f69e9bd82c@spud> References: <20251009-max25014-v4-0-6adb2a0aa35f@gocontroll.com> <20251009-max25014-v4-1-6adb2a0aa35f@gocontroll.com> Precedence: bulk X-Mailing-List: linux-fbdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="GWNRbICvH2XFNKt7" Content-Disposition: inline In-Reply-To: --GWNRbICvH2XFNKt7 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Oct 09, 2025 at 10:55:42AM -0400, Frank Li wrote: > On Thu, Oct 09, 2025 at 08:48:25AM +0200, Maud Spierings via B4 Relay wro= te: > > From: Maud Spierings >=20 > Subject needn't double bindings. >=20 > dt-bindings: backlight: Add max25014 support >=20 > > > > The Maxim MAX25014 is a 4-channel automotive grade backlight driver IC > > with integrated boost controller. > > > > In the current implementation the control registers for channel 1, > > control all channels. So only one led subnode with led-sources is > > supported right now. If at some point the driver functionality is > > expanded the bindings can be easily extended with it. >=20 > Need descript hardware, not driver. Need descript full functions even tho= ugh > driver have not implement yet. >=20 > > > > Signed-off-by: Maud Spierings > > --- > > .../bindings/leds/backlight/maxim,max25014.yaml | 109 +++++++++++++= ++++++++ > > MAINTAINERS | 5 + > > 2 files changed, 114 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/leds/backlight/maxim,max= 25014.yaml b/Documentation/devicetree/bindings/leds/backlight/maxim,max2501= 4.yaml > > new file mode 100644 > > index 0000000000000..496520e1374e5 > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/leds/backlight/maxim,max25014.y= aml > > @@ -0,0 +1,109 @@ > > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > > +%YAML 1.2 > > +--- > > +$id: http://devicetree.org/schemas/leds/backlight/maxim,max25014.yaml# > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > + > > +title: Maxim max25014 backlight controller > > + > > +maintainers: > > + - Maud Spierings > > + > > +properties: > > + compatible: > > + enum: > > + - maxim,max25014 > > + > > + reg: > > + maxItems: 1 > > + > > + "#address-cells": > > + const: 1 > > + > > + "#size-cells": > > + const: 0 > > + > > + enable-gpios: > > + maxItems: 1 > > + > > + interrupts: > > + maxItems: 1 > > + > > + power-supply: > > + description: Regulator which controls the boost converter input ra= il. > > + > > + pwms: > > + maxItems: 1 > > + > > + maxim,iset: > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + maximum: 15 > > + default: 11 > > + description: > > + Value of the ISET register field. This controls the current scal= e of the > > + outputs, a higher number means more current. >=20 > Can't use register value directly, need use standard unit. or percentage >=20 > 100: means max, 0: min. =46rom that datasheet, it seems like the values here don't neatly map to currents, because it depends on the value of the iref register. I don't love percentages here either, too much of a force-fit for me. If current is used, a property for the reference resistor will be needed, to compute the register values. That only makes sense to me if Maxim/Analog provide a formula that can be used to calculate the appropriate register value, and I did not find one in the datasheet from my quick skim, only two example current tables. Sure, those two examples can be reverse-engineered to give a way to compute it, but can we be sure that the numbers apply across the whole range of permitted values for the resistor? I don't like using register values for stuff, but I think it is the most accurate and least likely to cause problems way of representing this. Maud, on the language used - its the ISET field in the ISET register, I think the property should make that clear. > > +patternProperties: > > + "^led@[01]$": Why does this have [01] if reg has to be zero? > > + type: object > > + description: Properties for a string of connected LEDs. > > + $ref: common.yaml# > > + > > + properties: > > + reg: > > + const: 0 > > + > > + led-sources: > > + allOf: > > + - minItems: 1 > > + maxItems: 4 > > + items: > > + minimum: 0 > > + maximum: 3 > > + default: [0, 1, 2, 3] > > + > > + default-brightness: > > + minimum: 0 > > + maximum: 100 > > + default: 50 > > + > > + required: > > + - reg > > + > > + additionalProperties: false >=20 > there are $ref, should use unevaluatedProperties: false Not always, looks like they've listed some properties from the file, which would make addtionalPropeties: false correct if they dont want the other properties in the file to be used. >=20 > Frank > > + > > +required: > > + - compatible > > + - reg > > + > > +additionalProperties: false > > + > > +examples: > > + - | > > + #include > > + #include > > + > > + i2c { > > + #address-cells =3D <1>; > > + #size-cells =3D <0>; > > + > > + backlight@6f { > > + compatible =3D "maxim,max25014"; > > + reg =3D <0x6f>; > > + enable-gpios =3D <&gpio1 4 GPIO_ACTIVE_HIGH>; > > + interrupt-parent =3D <&gpio1>; > > + interrupts =3D <2 IRQ_TYPE_EDGE_FALLING>; > > + power-supply =3D <®_backlight>; > > + pwms =3D <&pwm1>; > > + maxim,iset =3D <7>; > > + > > + #address-cells =3D <1>; > > + #size-cells =3D <0>; > > + > > + led@0 { > > + reg =3D <0>; > > + led-sources =3D <0 1 2 3>; > > + default-brightness =3D <50>; > > + }; > > + }; > > + }; > > diff --git a/MAINTAINERS b/MAINTAINERS > > index 47fbc5e06808f..be5e2515900ce 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -15171,6 +15171,11 @@ F: Documentation/userspace-api/media/drivers/m= ax2175.rst > > F: drivers/media/i2c/max2175* > > F: include/uapi/linux/max2175.h > > > > +MAX25014 BACKLIGHT DRIVER > > +M: Maud Spierings > > +S: Maintained > > +F: Documentation/devicetree/bindings/leds/backlight/maxim,max25014.yaml > > + > > MAX31335 RTC DRIVER > > M: Antoniu Miclaus > > L: linux-rtc@vger.kernel.org > > > > -- > > 2.51.0 > > > > --GWNRbICvH2XFNKt7 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCaOf9DAAKCRB4tDGHoIJi 0p3tAP47AzB5bTLsDsM2hZCp4QQOrxzGbZd7QeTNZnPvuVKVjAD/ajHvzPM9GJH6 JrmJ4TzHGEQovDKBG7x28JpYUVrfTQ8= =7s2i -----END PGP SIGNATURE----- --GWNRbICvH2XFNKt7--